Nutrition - Articles in Press

Melanocortin-3 receptor gene variants: Association with childhood obesity and eating behavior in Chilean families - Corrected Proof

A.M. Obregón, P. Amador, M. Valladares, G. Weisstaub, R. Burrows, J.L. Santos — 2010-02-08

Abstract: Objective: To evaluate the association between melanocortin-3 receptor common genetic polymorphisms with childhood obesity and eating behavior in Chilean families.Methods: Two hundred twenty-nine obese children (6–12 y old, body mass index >95th percentile of Centers for Disease Control and Prevention/National Center for Health Statistics, 2000) and 270 parents were selected. Genotypes for MC3R genetic markers −239A>G, 17C>A (Thr6Lys), 241G>A (Val81Ile), +2138InsCAGACC, and microsatellite D20s32e were determined. Eating behavior scores were computed using the Child Eating Behavior Questionnaire and a shorter version of the Three Factor Eating Questionnaire adapted for evaluating eating inclinations in children. Genotype-obesity associations were assessed by the Transmission Disequilibrium Test. Non-parametric tests were used to compare eating behavior scores across study groups.Results: Allelic frequencies of −239G, 17A, 241A, and +2138InsCAGACC were estimated as 4.5%, 5.9%, 5.6%, and 17.6%, respectively, in obese children. The Transmission Disequilibrium Test in case–parent trios revealed no significant associations between childhood obesity and genetic markers, including the microsatellite D20s32e. In girls, we found significantly higher scores of the emotional eating subscale in carriers of the +2138InsCAGACC compared with non-carriers (P=0.04). In boys, carriers of 17A and 241A showed lower scores for the emotional eating subscale (P=0.01), whereas carriers of +2138InsCAGACC showed significantly lower scores for the enjoyment of food subscale compared with non-carriers (P=0.04).Conclusions: There is not sufficient evidence to support the contribution for common melanocortin-3 receptor variants in childhood obesity. However, our results are concordant for a role of melanocortin-3 receptor variants in some dimensions of eating behavior such as emotional eating and enjoyment of food.

Mitochondrial HMG-CoA synthase partially contributes to antioxidant protection in the kidney of stroke-prone spontaneously hypertensive rats - Corrected Proof

2010-02-08

Abstract: Objective: Increased oxidative stress plays an important role in cardiovascular diseases including hypertension and stroke. Evidence has indicated that ketone bodies could exert antioxidative effects. We explored the role of renal mitochondrial 3-hydroxy-3-methylglutaryl-coenzyme A synthase (HMGCS2) expression, a key control site of ketogenesis, in stroke-prone spontaneously hypertensive rats (SHRSPs) and their ancestral hypertensive but stroke-resistant spontaneously hypertensive rats (SHRs).Methods: Two groups of SHRSPs were fed a standard chow or standard chow supplemented with clofibrate (an agonist of HMGCS2 promoter), respectively, and SHRs fed with a standard chow were used as controls. The renal levels of HMGCS2, Akt, and phosphorylated protein kinase B (Akt) were measured by western blotting. Malondialdehyde, catalase, superoxide dismutase, and glutathione peroxidase were detected by assay kits.Results: Compared with SHRs, lower HMGCS2 protein expression, enhanced phosphorylated Akt signal, higher malondialdehyde levels, and higher catalase activity were observed in kidney tissues in SHRSPs (P < 0.05). No differences in superoxide dismutase and glutathione peroxidase activities were observed between SHRSPs and SHRs. Clofibrate treatment significantly upregulated renal HMGCS2 expressions, inhibited phosphorylation of Akt, and decreased malondialdehyde levels and catalase activities in SHRSP kidney tissues (P < 0.05).Conclusion: These results demonstrated the difference in HMGCS2 expression and oxidative stress in kidney tissues between SHRSPs and their SHR controls. The enhanced oxidative stress was partly due to the lower HMGCS2 expression regulated possibly by the Akt signaling pathway.

Glutamine-supplemented total parenteral nutrition improves immunological status in anorectic patients - Corrected Proof

2010-02-01

Abstract: Objective: Glutamine is an important substrate for critical cells of the immune system, in particular lymphocytes and macrophages, and it is considered a conditionally essential amino acid. Several studies have indicated that glutamine-enriched total parenteral nutrition improves immunologic status and shortens length of stay of critically ill patients. We investigated the effect of total parenteral nutrition supplemented with glutamine on the immune system in anorectic patients.Methods: Thirty-six anorectic patients were randomized to receive standard parenteral nutrition or parenteral nutrition supplemented with glutamine 0.18 g · kg−1 · d−1 for 20 d. To evaluate the immune system status, we determined serum levels of neopterin and insulin growth factor-1 and lymphocyte count at baseline and after 10 and 20 d from the beginning of the therapy.Results and Conclusions: The results showed a significant increase of the serum levels of neopterin after 10 d of treatment with glutamine (26.44 ± 3.08 versus 6.75 ± 1.73 nmol/L, P < 0.001), thus proving a probable stimulating action carried out by glutamine on the immune system, as testified by the increase of lymphocytes.

Increased Maillard reaction products intake reduces phosphorus digestibility in male adolescents - Corrected Proof

2010-02-01

Abstract: Objective: To examine the effects of consuming diets rich in Maillard reaction products (MRPs) on phosphorus bioavailability in male adolescents.Methods: A 2-wk randomized two-period crossover trial was performed among healthy male adolescents aged 11–14 y (n = 20), with a 40-d washout period. The diets consumed were rich (brown diet) or poor (white diet) in MRPs. Three-day balances were performed on the last of each dietary period, and fasting blood samples were obtained. Dietary phosphorus utilization was examined by phosphorus intake in diet and phosphorus output in feces and urine, as measured colorimetrically by the vanadomolibdate procedure. Serum phosphorus, parathyroid hormone, and total alkaline phosphatase were determined.Results: A tendency to increase daily phosphorus fecal excretion was observed subsequent to the brown diet consumption compared with the white diet (P = 0.10), which led to significant reductions in phosphorus apparent absorption (P = 0.03) and fractional absorption (P = 0.04). Values of apparent phosphorus retention and bioavailability tended to decrease after the high-MRP diet. Serum parameters analyzed remained unchanged between diets and were within normal values.Conclusion: The consumption of a rich-MRP diet in male adolescents had a negative influence on dietary phosphorus absorption, tending to decrease the phosphorus balance. Given the actual dietary habits of adolescents, possible long-term repercussions of this kind of diet should be studied.

Lipodystrophy, lipid profile changes, and low serum retinol and carotenoid levels in children and adolescents with acquired immunodeficiency syndrome - Corrected Proof

2010-01-29

Abstract: Objective: To assess serum retinol and levels of carotenoids in children and adolescents with acquired immunodeficiency syndrome (AIDS) and to correlate low serum retinol and carotenoid levels with the presence of lipodystrophy, lipid profile changes, lipid peroxidation, and insulin resistance.Methods: A cross-sectional, controlled observational study was carried out with 30 children and adolescents with AIDS (mean age 9.1 y) receiving antiretroviral therapy (median length of treatment 28.4 mo), including 30 uninfected healthy controls matched for age and gender. Clinical and laboratory assessments were performed to determine nutritional status, presence of lipodystrophy, serum concentrations of retinol, β-carotene, lycopene, lipid profile (high-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triacylglycerols), lipid peroxidation (thiobarbituric acid-reactive substances), glycemia, and serum insulin (homeostasis model assessment for insulin resistance, cutoff point >3). Statistical analysis was done with chi-square test and Student's t test.Results: Lipodystrophy was observed in 53.3% of patients with AIDS, and dyslipidemia was detected in 60% and 23% of subjects with human immunodeficiency virus and control subjects, respectively (P = 0.004). A higher prevalence of retinol deficiency (60% versus 26.7%, P = 0.009) and β-carotene deficiency (23.3% versus 3.3%, P = 0.026) was found in the group with human immunodeficiency virus than in the control group. No correlation was found for low retinol and β-carotene levels, changes in lipid and glucose metabolism, or lipodystrophy in children and adolescents with AIDS.Conclusion: Despite the high frequency of dyslipidemia, lipodystrophy, and retinol and β-carotene deficiencies, it was not possible to demonstrate a correlation of these findings with lipid peroxidation and insulin resistance. More studies are needed to investigate the causes of retinol and β-carotene deficiencies in this population and the clinical consequences of these findings.

Effect of whole walnuts and walnut-skin extracts on oxidant status in mice - Corrected Proof

2010-01-29

Abstract: Objective: To evaluate the effect of the intake of whole walnuts and walnut fractions on the oxidant status in mice.Methods: Thirty-six C57BL/6J male mice were randomized to be fed one of three diets: 1) a standard diet (control group), 2) a standard diet with 10% of whole walnuts (walnut-diet group), or 3) a standard diet with 2% of walnut skins (walnut-skin-diet group) for 8 wk. The plasma antioxidant capacity was measured by oxygen radical-absorbance capacity and plasma ferric-reducing antioxidant potential. Conjugated diene formation and reduced glutathione levels were also analyzed.Results: We observed no changes in plasma oxidation capability between the walnut and walnut-skin groups with the exception of conjugated dienes. Plasma total antioxidant capacity and the ratio between reduced and oxidized forms of glutathione were lower in the walnut and walnut-skin groups than in the control group.Conclusion: The decrease in the antioxidant burden observed in enzymatic and non-enzymatic antioxidant systems after sustained consumption of a whole-walnut or a walnut-skin diet in mice may be related to the plasma oxidation capability being maintained in the groups consuming the walnut diets.

Impact of lipid emulsion containing fish oil on outcomes of surgical patients: Systematic review of randomized controlled trials from Europe and Asia - Corrected Proof

Chen Wei, Jiang Hua, Cai Bin, Karen Klassen — 2010-01-29

Abstract: Objective: This study aimed to systematically review the clinical efficacy of lipid emulsion containing fish oil in surgical patients.Methods: Medline, SCI, Embase, Cochrane Library, and Chinese Biomedicine Database were searched for studies published before January 1, 2009 that were randomized controlled trials for postoperative patients. Parenteral nutrition with or without fish oil emulsion was the only difference between the intervention and control groups. Methodologic quality assessment was based on the Cochrane Handbook for Systematic Reviews of Interventions Version 5.0.1 and Jadad's score scale. RevMan 5.0 statistical software was used for meta-analysis.Results: Six trials met all inclusion criteria and were enrolled for final meta-analysis. The aggregated results of the trails showed that fish oil was associated with no mortality advantage. There was a significant reduction in infectious complications in patients receiving fish oil (relative risk 0.49, 95% confidence interval 0.26–0.93, P=0.03). The result on length of hospital stay showed a trend of shortening by 3.06 d associated with receiving fish oil. However, the difference was not significant. When excluding one obviously heterogeneous study and aggregating the other three remaining studies, results showed significantly shortening of length of hospital stay associated with receiving fish oil. Fish oil also significantly shortened length of stay in the intensive care unit by 2.07 d.Conclusion: The administration of lipid emulsion containing fish oil to patients undergoing elective major operations improves outcomes. The infectious complications are significantly fewer and length of hospitalization significantly shortened for patients treated with lipid emulsion containing fish oil. Further well-designed randomized controlled trials are needed to demonstrate the cost effectiveness of lipid emulsion containing fish oil to postoperative patients.

Evaluation of the nutrient-upgraded rodent food bar for rodent spaceflight experiments - Corrected Proof

2010-01-29

Abstract: Objective: Selection of an appropriate diet for rodent spaceflight experiments is critical and may have significant effects on mission results. The National Aeronautics and Space Administration (NASA) rodent food bar (RFB) was reformulated and designated as the nutrient-upgraded RFB (NuRFB). The objectives of this study were to determine whether the NuRFB nutrient formulation meets the 1995 National Research Council (NRC) nutrient recommendations and whether the NuRFB can be used for short-term (45-d) and long-term (90-d) spaceflight experiments.Methods: Nutrient and moisture analyses of the NuRFB were performed. Young (age 13–14 wk) male Sprague-Dawley rats (n=16/group) were individually caged and fed a diet treatment consisting of 1) NuRFB, 2) RFB, or 3) modified AIN-93G containing 4% instead of the 7% fat for 45- or 90-d. At the end of the study, organs were weighted, and serum clinical chemistry indicators of organ function and hematologic measurements were determined.Results: Chemical analysis of the diet ingredients showed that the NuRFB met the 1995 NRC nutrient recommendations for rats. Subsequent animal feeding studies showed that NuRFB was comparable to RFB and modified AIN-93G for supporting rat growth and body weight maintenance. In addition, the safety of the NuRFB for use as a spaceflight diet was indicated by the absence of changes in organ weight or function.Conclusion: Based on the study results, the NuRFB performed similarly to the RFB and met the criteria necessary for short-term and long-term rodent spaceflight experiments.

Apolipoprotein A-I positively associated with diabetes in women independently of apolipoprotein E genotype and apolipoprotein B levels - Corrected Proof

2010-01-29

Abstract: Objective: Given the elevated apolipoprotein (apo) A-I level enhancement of type 2 diabetes among Turks, the interrelation among it, apoB, and apoE genotype with respect to the likelihood of diabetes and metabolic syndrome (MetS), and the role of gender need further investigation.Methods: A random sample of Turkish adults genotyped for apoE with measured serum apoB and apoA-I concentrations was studied cross-sectionally. Apo ɛ2/ɛ4 genotype was excluded to avoid confounding. MetS was identified by modified criteria of the Adult Treatment Panel III.Results: Among 1673 participants, ɛ3 homozygotes prevailed in 74%, apoE2 (ɛ2/ɛ3, ɛ2/ɛ2) in 12%, and apoE4 (ɛ3/ɛ4, ɛ4/ɛ4) in 13%. Low-density lipoprotein cholesterol and apoB levels were significantly lower and apoE concentrations higher in the apoE2 than in the remaining groups. ApoA-I levels in female subjects were significantly higher than in the E4 group. Multivariable analysis for determinants of apoB showed apoE genotype, serum apoE, C-reactive protein, apoA-I, and triacylglycerol levels to be major independent covariates. Logistic regression analyses for MetS, adjusted for potential confounders, revealed that apoB is linked to MetS in men independently of serum triacylglycerols and apoE2 group, whereas that in women in the apoE2 group was associated with MetS by mediation by triacylglycerols or apoB. The independent inverse association of apoA-I with MetS was considered apparent. Multi-adjusted likelihood of diabetes was associated only with triacylglycerol levels and, in women, with apoA-I (odds ratio 1.43, 95% confidence interval 1.10–1.86, per 1 SD increment).Conclusion: The confirmed positive association of serum apoA-I with diabetes in Turkish women is independent of apoE genotype and apoB levels.

Neonatal exposure to sucralose does not alter biochemical markers of neuronal development or adult behavior - Corrected Proof

Henrik Viberg, Anders Fredriksson — 2010-01-29

Abstract: Objective: Sucralose, a high-intensity sweetener, has been approved as a general-purpose sweetener in all food since the late 1990s. Due to its good taste and physiochemical profile, its use has increased and sucralose is considered a way of managing health and an option to improve the quality of life in the diabetic population. Recently high concentrations of sucralose have been found in the environment. Other environmental pollutants have been shown to induce neurotoxic effects when administered during a period of rapid brain growth and development. This period of rapid brain growth and development is postnatal in mice and rats, spanning the first 3–4 wk of life, reaching its peak around postnatal day 10, whereas in humans, brain growth and development is perinatal. The proteins calcium/calmodulin-dependent protein kinase II, growth-associated protein-43, synaptophysin, and tau play important roles during brain growth and development.Methods: In the present study, mice were orally exposed to 5–125 mg of sucralose per kilogram of body weight per day during postnatal days 8–12. Twenty-four hours after last exposure, brains were analyzed for calcium/calmodulin-dependent protein kinase II, growth-associated protein-43, synaptophysin, and tau, and at the age of 2 mo the animals were tested for spontaneous behavior.Results: The protein analysis showed no alterations in calcium/calmodulin-dependent protein kinase II, growth-associated protein-43, synaptophysin, or tau. Furthermore, there were no disturbances in adult behavior or habituation after neonatal sucralose exposure.Conclusion: The present study shows that repeated neonatal exposure to the artificial sweetener sucralose does not result in neurotoxicity, which supports that sucralose seems to be a safe alternative for people who want or need to reduce or substitute glucose in their diet.

β-Carotene accumulation in 3T3-L1 adipocytes inhibits the elevation of reactive oxygen species and the suppression of genes related to insulin sensitivity induced by tumor necrosis factor-α - Corrected Proof

Hiroyuki Kameji, Kazuki Mochizuki, Noriyuki Miyoshi, Toshinao Goda — 2010-01-25

Abstract: Objective: β-Carotene is an abundant carotenoid with potent antioxidative activities and accumulates in adipose tissue. However, its physiologic functions are poorly understood. In this study, we examined whether accumulation of β-carotene for 4 d in insulin-resistant 3T3-L1 adipocytes alters the expression of genes related to insulin sensitivity.Methods: The 3T3-L1 adipocytes were treated with/without 10 or 20μM β-carotene during differentiation for 4 d. The cells treated with 10μM β-carotene for 4 d were subsequently incubated with/without 5 ng/mL of tumor necrosis factor-α for 48h in the medium without β-carotene. The mRNA levels of genes in the cells and adiponectin protein levels in the medium were determined by real-time reverse transcription–polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. Reactive oxygen species levels in the cells were assessed by oxidation of 2′,7′-dichlorodihydrofluorescein diacetate.Result: β-Carotene treatment at a concentration of 20μM, but not 10μM, in 3T3-L1 adipocytes during differentiation for 4 d enhanced the expression of genes related to insulin sensitivity, including adiponectin, adipocyte lipid-binding protein, glucose transporter-4, peroxisome proliferator-activated receptor-γ2, and adiponectin protein in the medium. Tumor necrosis factor-α treatment repressed the expression of these genes and adiponectin protein in the medium and induced reactive oxygen species levels. In contrast, cells that accumulated β-carotene at a concentration of 10μM did not show these alterations.Conclusion: The accumulation of the β-carotene in 3T3-L1 adipocytes restores the expression of genes related to insulin sensitivity and reactive oxygen species levels in insulin-resistant adipocytes.

Longitudinal relationship between dietary ω-3 fatty acids and periodontal disease - Corrected Proof

2010-01-25

Abstract: Objective: Fish oil has anti-inflammatory actions that may benefit periodontal health. We investigated the longitudinal relation between dietary ω-3 fatty acids (FAs), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) to periodontal disease in community-dwelling elderly.Methods: Fifty-five participants aged 74 y were randomly selected from a longitudinal interdisciplinary study of aging. Dietary intake data were obtained by a 3-d weighed food intake. The dietary intakes of energy, DHA, and EPA were calculated based on the Standard Food Composition Tables in Japan. Dental examinations were carried out at baseline and once a year for 5 y. The number of teeth with periodontal progression over 5 y per person was calculated as “periodontal disease events.” Negative binomial regression analysis was conducted, which included DHA, EPA, and other covariates as independent variables to estimate the influence on periodontal disease events. Longitudinal data were analyzed for participants for whom data were available for 5 y (n=36).Results: Low DHA intake was significantly associated with more periodontal disease events. The mean number of periodontal disease events for participants who consumed the lowest tertile of DHA was approximately 1.5 times larger (lowest tertile, incidence rate ratio 1.49, 95% confidence interval 1.01–2.21) than the reference group (highest tertile of DHA consumption), after simultaneously adjusting for possible confounders.Conclusion: The findings suggest there may be an inverse, independent relation of dietary DHA intake to the progression of periodontal disease in older people.

Acute and long-term nutrient-led modifications of gene expression: Potential role of SIRT1 as a central co-ordinator of short and longer-term programming of tissue function - Corrected Proof

Mark J. Holness, Paul W. Caton, Mary C. Sugden — 2010-01-25

Abstract: Environmental factors can influence the acute and longer-term risks of developing diseases, including type 2 diabetes mellitus and cardiovascular disease; however, the underlying mechanism remains elusive. Increasing evidence suggests that these effects can be achieved by modification of metabolic gene expression. These include acute changes in histone methylation, acetylation, phosphorylation, and ubiquitination and longer-term DNA silencing elicited by DNA methylation. Thus, an increased risk of disease may reflect acute or chronic stable modification of genes that regulate nutrient handling, leading to altered nutrient utilization (increased lipid oxidation at the expense of glucose utilization) and/or changes in the balance between nutrient storage and energy production, thereby favoring the development of obesity. The review addresses the hypothesis that early-life epigenetic programming of gene expression could be mirrored by changes in acute function of nuclear receptors, in particular the peroxisome proliferator-activated receptors, achieved by enzymes that are more conventionally involved in regulating DNA methylation and post-transcriptional modification of histones. Emphasis is placed on the potential importance of the protein deacetylase sirtuin-1 as a central co-ordinator.

Effect of the methylenetetrahydrofolate reductase (MTHFR 677C>T) polymorphism on plasma homocysteine concentrations in healthy children is influenced by consumption of folate-fortified foods - Corrected Proof

2010-01-25

Abstract: Objective: To explore the influence of folate-fortified foods (ready-to-eat [RTE] breakfast cereals or fruit-juice drinks) on the relation between the methylenetetrahydrofolate reductase (MTHFR 677C>T) polymorphism and plasma total homocysteine (tHcy) concentrations in healthy children.Methods: This was a cross-sectional study by face-to-face interview. A total of 186 sixth-grade students participated from randomly selected primary schools in Volos, Greece. Fasting plasma tHcy, folate, and vitamin B12 were measured. The MTHFR genotypes were determined. Anthropometric data were collected and dietary intake was assessed by two non-consecutive 24-h recalls. Participants were characterized as non-consumers of RTE breakfast cereals or fruit-juice drinks if there was no report of any such food during the 24-h recall interviews; all other children were classified as consumers.Results: Geometric means for plasma tHcy were higher, whereas plasma folate was lower in non-consumers compared with consumers. The sample was divided by consumption status (yes or no) to explore the significance of each polymorphism depending on consumption status. The association between the genotype and tHcy was restricted to non-consumers (P<0.05). Specifically, only in children who did not consume RTE breakfast cereals or fruit-juice drinks did the TT genotype carriers exhibit higher tHcy concentrations when compared with C-allele carriers (P<0.05). In contrast, in consumers, circulating tHcy was similar regardless of genotype.Conclusion: These observational findings support a beneficial effect of RTE breakfast cereals and fruit-juice drinks on lowering plasma tHcy and improving folate status in children. Also, consumption of folate-fortified foods modulates the association of the MTHFR 677C>T polymorphism with tHcy, suggesting that habitual consumption of folate-fortified foods is a practical approach in providing consistent protection to those children who may benefit the most, i.e., carriers of the TT genotype.

Effects of maternal undernutrition during lactation on estrogen and androgen receptor expressions in rat ovary at puberty - Corrected Proof

2010-01-25

Abstract: Objective: The aim of this study was to evaluate the effects of maternal protein and energy-restricted diets during lactation in folliculogenesis and its relations to androgen and estrogen receptors in the offspring at puberty.Methods: At parturition, dams were randomly assigned to a control (C) group, with free access to a standard laboratory diet containing 23% protein; a protein–energy-restricted (PER) group, with free access to an iso-energy and protein-restricted diet containing 8% protein; and an energy-restricted (ER) group, receiving standard laboratory diet in restricted quantities. After weaning, female pups had free access to standard laboratory diet.Results: The number of preantral (C 13.72 ± 2.87, PER 26.36 ± 3.03, ER 26.88 ± 2.31, P < 0.05) and small antral (C 9.32 ± 1.32, PER 17.64 ± 2.33, ER 17.04 ± 2.22, P < 0.05) follicles was significantly increased by maternal malnutrition. The number of primordial follicles (C 10.57 ± 1.61, PER 4.30 ± 0.62, ER 6.28 ± 1.30, P < 0.05), Graafian follicles (C 1.04 ± 0.09, PER 0.52 ± 0.10, ER 0.36 ± 0.11, P < 0.01), and corpus luteum (C 4.84 ± 0.62, PER 2.80 ± 0.50, ER 3.24 ± 0.27, P < 0.05) was significantly reduced. Maternal protein- and energy-restricted diets led to a significant decrease in the androgen (C 9815 ± 1015, PER 6071 ± 838.7, ER 5811 ± 699.3, P < 0.05) and estrogen (C 0.79 ± 0.244, PER 0.12 ± 0.035, ER 0.20 ± 0.036, P < 0.05) α-receptors. In growing follicles, androgen receptor was immuno-expressed in granulosa and theca cells. Estrogen receptor-α was mainly expressed in stroma cells.Conclusion: Our results suggest that maternal protein- and energy-restricted diets during lactation can disturb the follicular development of the offspring, probably by reducing the number of androgen and estrogen receptors in the ovary.

Reducing pressure ulcer risks in activity-restricted patients: A national imperative - Corrected Proof

Larry H. Bernstein — 2010-01-25

The article “Malnutrition and pressure ulcer risk in adults and Australian health care facilities” demonstrates what can be done to relieve a serious worldwide problem. An impressive study of 2208 acute and 839 aged care subjects in Queensland found an association between nutritional status and the presence and severity of pressure ulcers with adjusted odds ratios of 2.6 and 2.0, respectively, in acute care and residential care facilities, related to the severity of nutritional impairment. The study has the power to elicit the nutritional component of preventive measures.

Perioperative tight glucose control with hyperinsulinemic-normoglycemic clamp technique in cardiac surgery - Corrected Proof

2010-01-25

Abstract: Objective: Previous attempts to achieve tight glucose control in surgical patients were associated with a significant incidence of hypoglycemia. The purpose of this study was to evaluate the efficacy of perioperative glucose and insulin administration while maintaining normoglycemia using a hyperinsulinemic-normoglycemic clamp technique.Methods: We studied 70 non-diabetic and 40 diabetic patients undergoing cardiac procedures. Before induction of anesthesia, insulin was administered at 5 mU · kg−1 · min−1. Blood glucose (BG) concentrations were determined every 15–30min. Dextrose 20% was infused at a rate adjusted to maintain BG within 3.5–6.1mmol/L. At the end of surgery, insulin infusion was decreased to 1 mU · kg−1 · min−1 and continued for 24h. The mean ± standard deviation of BG and the percentage of BG values within the target range were calculated perioperatively. Episodes of severe hypoglycemia, i.e., BG <2.2mmol/L, were recorded.Results: The mean BG remained within target at all times. Normoglycemia in non-diabetic patients was achieved in 92.8% of measurements during and in 83.2% after surgery. In diabetic patients 87.4% of values were within target intraoperatively and 76.7% after surgery. The rate of severe hypoglycemia was 2.7% (three patients). In non-diabetic patients the incidence of severe hypoglycemia was 0.2% of measurements during and 0.1% after surgery. Diabetic patients showed only one episode of severe hypoglycemia after surgery (0.1%).Conclusion: Perioperative use of a hyperinsulinemic-normoglycemic clamp technique established and maintained normoglycemia in patients undergoing cardiac surgery with little risk of hypoglycemia.

Malabsorption may contribute to malnutrition in the elderly - Corrected Proof

Terry Bolin, Marian Bare, Gideon Caplan, Suzie Daniells, Margaret Holyday — 2010-01-25

Abstract: Malnutrition, either actually malnourished or at risk, is present in 80% of the elderly population presenting to hospital for admission. Although many factors contribute to this situation, one yet to be explored is malabsorption. We therefore aimed to assess nutritional status as well as the prevalence of altered mucosal permeability and celiac disease among a group of elderly patients presenting for rehabilitation. Forty-eight subjects were recruited (16 females) with a mean age of 83.7 (SD 6.1), body mass index 21.8kg/m2 (SD 3.9), mini-nutritional assessment (MNA) 19.5 (SD 3.4). They had no current gastrointestinal symptoms and undertook an assessment of mucosal permeability using the dual sugar absorption test of lactulose (7.5g) and rhamnose (1g). Ten of the 48 subjects had increased mucosal permeability with an L:R ration ranging from 0.0860 to 7.706 (N 0.01–0.08). These subjects were all at risk or malnourished according to the MNA score and they had a significantly lower mean MNA score of 17.2 (SD 3.5) compared to normal absorbers with a mean of 19.5 (SD 3.4). Two of the subjects had positive tissue trans-glutaminase antibodies. The higher risk of potential malabsorption in this elderly population has significant implications both for nutritional supplementation and for drug absorption as well as being a possible major contributor to malnutrition.

High-dose selenium for critically ill patients with systemic inflammation: Pharmacokinetics and pharmacodynamics of selenious acid: A pilot study - Corrected Proof

2010-01-18

Abstract: Objective: Systemic inflammatory response syndrome is characterized by increased urinary excretion of selenium and low serum concentration. Repletion by parenteral selenite is the most efficacious form of supplementation. However, the optimum safe dose and mode of administration remain controversial. We aimed to determine pharmacokinetic and pharmacodynamic profiles of selenite and estimate a safe dose to optimize selenium status.Methods: A prospective, randomized, pilot study in 20 patients with systemic inflammatory response syndrome compared a high-dose (HD) group that received a loading dose of selenium as selenite 15.18 μmol over 2 h and thereafter 10.12 μmol/d as a continuous intravenous infusion (CIV) for 10 d with a very–high-dose (VHD) group that received a loading dose of 25.30 μmol over 2 h and thereafter 20.24 μmol as a CIV for 10 d. Clinical outcome was evaluated by length of stay in the intensive care unit, incidence of ventilator-associated pneumonia, and Sequential Organ Failure Assessment score.Results: Patients in group HD (n = 10, age 54 ± 23 y) had an Acute Physiology and Chronic Health Evaluation II score of 23 ± 5 and a Sequential Organ Function Assessment score of 10 ± 2. Those in group VHD (n = 10, age 41 ± 19 y) had scores of 21 ± 7 and 8 ± 3, respectively. Pharmacokinetic concentration/time curves for serum selenium overlapped but were independent of dose, whereas the pharmacodynamics were different, showing maximum glutathione peroxidase activity only with VHD. Glutathione peroxidase decreased after day 7 independently of the selenium dose. Clinical outcomes were similar in both groups.Conclusion: A bolus loading dose of selenite providing 2000 μg of selenium (25.30 μmol) followed by a CIV of 1600 μg/d (20.24 μmol/d) for 10 d is most effective at returning serum selenium to physiologic levels and safely maximizing glutathione peroxidase activity.

Suboptimal iodine status of Australian pregnant women reflects poor knowledge and practices related to iodine nutrition - Corrected Proof

Karen E. Charlton, Luke Gemming, Heather Yeatman, Gary Ma — 2010-01-18

Abstract: Objective: To assess the iodine status and knowledge and practices related to iodine nutrition of Australian women during pregnancy.Methods: A cross-sectional study was conducted at a public antenatal clinic in the Illawarra region of New South Wales. One hundred thirty-nine pregnant women across all trimesters provided a spot urine sample (n = 110) and completed a short questionnaire (n = 139) in English. Iodine status was based on World Health Organization/International Committee for the Control of Iodine Deficiency Disorders urine iodine concentration (UIC) categories.Results: Median UIC was 87.5 μg/L (interquartile range 62); only 14.5% of participants had an adequate UIC value ≥150 μg/L. Fifteen percent of women had very low UIC values (<50 μg/L), whereas 45.5% had values in the 50- to 99-μg/L range. Knowledge of the adverse health effects of an inadequate iodine intake was poor. Approximately half the participants were able to indicate good dietary sources of iodine, such as fish (58%) and iodized salt (51%). However, a high level of confusion regarding other foods was evident. Only a small number of participants (11%) reported that they had intentionally changed their diet to increase iodine intake during pregnancy, but 59% indicated supplement use, of which 35% contained iodine. Those who were taking supplements that contained iodine had significantly higher UIC levels (139.1 μg/L) than those who were not (90.8 μg/L, P < 0.05).Conclusion: Public health strategies, including nutritional education and supplementation, are urgently required to improve the iodine status of pregnant women. Currently, no readily accessible information on iodine is available to women attending antenatal clinics in Australia.

Hyperglycemia-induced endoplasmic reticulum stress in endothelial cells - Corrected Proof

2010-01-18

Abstract: Objective: Hyperglycemia-induced endothelial cell dysfunction in vascular disease can occur due to increased oxidative stress and a concomitant increase in endoplasmic reticulum (ER) stress. To investigate whether these cellular stresses are independent or causally linked, we determined whether or not specific glycolytic intermediates that induce oxidative stress also induce ER stress.Methods: Human umbilical vein endothelial cells were treated with dextrose, partially metabolizable (e.g., fructose and galactose) and non-metabolizable sugars (e.g., 3-O-methyglucose), and various intermediates of the glycolytic and tricarboxylic acid pathways. Activation of the unfolded protein response and subsequent generation of ER stress was measured by the ER stress-responsive alkaline phosphatase method, and superoxide (SO) generation was measured using the hydro-ethidene–fluorescence method. The mitochondrial origin of the SO and the generation of ER stress by dextrose and the intermediate metabolites were confirmed with experiments using allopurinol and diphenyleneiodonium chloride to block SO generation by xanthine oxidase and nicotinamide adenosine dinucleotide phosphate oxidase, respectively.Results: Although ER stress could be induced by glycolytic intermediates up to and including pyruvate, the SO generation occurred in the presence of glycolytic and mitochondrial metabolites.Conclusion: Although the mitochondria are the site of signals generated by dextrose to initiate oxidative stress, the dextrose-induced ER stress, unlike SO generation, does not require pyruvate oxidation in the mitochondria.

Focus on the short- and long-term effects of ghrelin on energy homeostasis - Corrected Proof

Carine De Vriese, Jason Perret, Christine Delporte — 2010-01-18

Abstract: The endogenous ligand for the growth hormone secretagogue receptor, ghrelin, is a 28–amino-acid peptide acylated with an octanoyl group at the serine in position 3. Most of the circulating ghrelin results from its synthesis and secretion by the X/A-like endocrine cells from the stomach and proximal small intestine. Besides its potent growth hormone secretory action, ghrelin is a highly pleiotropic hormone, contributing significantly to the regulation of appetite and food intake control, gastrointestinal motility, gastric acid secretion, endocrine and exocrine pancreatic secretions, cell proliferation, glucose and lipid metabolism, and cardiovascular and immunologic processes. The purpose of this review is to consider the orexigenic effects of ghrelin on short-term regulation of food intake and long-term regulation of body weight, the implications of genetic ghrelin and growth hormone secretagogue receptor polymorphism, and the use of antagonists and agonists of ghrelin in pathophysiological conditions.

Oxidative stress and cognitive longevity - Corrected Proof

Michael J. Glade — 2010-01-18

Abstract: Objective: The potential relation between metabolic activity within the central nervous system and retention of cognitive functioning capacity was assessed.Methods: A detailed literature review was conducted and summarized.Results: A large body of scientific evidence describes the interactions among cognitive activity, oxidative stress, neurodegeneration, neuroprotection, cognitive aging, and retention of cognitive functioning ability.Conclusion: Maintenance of redox balance within the central nervous system can forestall cognitive decline and promote cognitive longevity.

Antioxidant supplementation had positive effects in old rat muscle, but through better oxidative status in other organs - Corrected Proof

2010-01-18

Abstract: Objective: Aged muscle is characterized by a defect in the ability of leucine to stimulate protein synthesis. We showed previously that antioxidant supplementation improved the anabolic response to leucine of old muscle and reduced inflammation. The aim of the present study was to determine if the positive effects observed in muscle could be related to an improvement of local muscle oxidative status.Methods: Two groups of 20-mo-old male Wistar rats were supplemented or not with rutin, vitamin E, vitamin A, zinc, and selenium during 7 wk. We measured body weight, food intake, oxidative status in muscle and other tissues, gastrocnemius muscle proteolytic activities, and liver glutathione metabolism.Results: Antioxidant supplementation had no effect on muscle antioxidant capacity, superoxide dismutase activities, and myofibrillar protein carbonyl content and induced an increase in muscle cathepsin activities. In other tissues, antioxidant supplementation increased liver glutathione (reduced plus oxidized glutathione) content, reduced oxidative damage in the liver and spleen (as measured by γ-keto-aldehyde content), and reduced heart thiobarbituric acid-reactive substances.Conclusion: Our results showed that the positive effects of antioxidant supplementation observed previously on the anabolic response to leucine of old muscle were not directly related to an improvement of in situ muscle oxidative status. It could result from reduced systemic inflammation/oxidative stress. The dialog between muscle and other organs should be studied more thoroughly, especially during aging.

Sulfur amino acids in methionine-restricted rats: Hyperhomocysteinemia - Corrected Proof

2010-01-18

Abstract: Objective: Dietary methionine restriction in Fischer-344 rats favorably influences visceral fat mass, insulin sensitivity, metabolic parameters, and longevity. However, little is known about the effects of methionine restriction on serum methionine and its downstream sulfur amino acids. We investigated the serum sulfur amino acid profile of male Fischer-344 rats fed a methionine-restricted diet for 3 mo.Methods and results: Using tandem mass spectrometry, we observed marked reduction in serum concentrations of methionine, cystathionine, cysteine, and taurine in methionine-restricted rats compared with control (P<0.001) and a 2.5-fold elevation of homocysteine (P<0.001).Conclusion: This suggests that homocysteine trans-sulfuration may be inhibited by methionine restriction, and that some of the effects of methionine restriction may be mediated by changes in sulfur amino acids downstream of methionine.

Bioavailability and catabolism of green tea flavan-3-ols in humans - Corrected Proof

2010-01-18

Abstract: Objective: The aim of this study was to investigate green tea flavan-3-ol catabolism and plasma pharmacokinetic and urinary excretion by high-performance liquid chromatography with tandem mass spectrometry to evaluate their absolute bioavailability by taking into account all known and some unknown catabolites deriving from their interaction with the gastrointestinal tract and its host microflora.Methods: A feeding study was carried out in 20 healthy human volunteers who ingested 400mL of a ready-to-drink green tea containing approximately 400μmol of flavan-3-ols. Urine and plasma were collected for 4 and 24h, respectively, and 39 relevant catabolites were identified in these biological fluids by tandem mass spectrometry.Results: In biological fluids, 39 relevant flavan-3-ol catabolites were identified. In plasma, (−)-epigallocatechin-3-gallate was the only unmetabolized compound and the highest in absolute concentration compared with (−)-epigallocatechin and (−)-epicatechin conjugates. Colonic microflora-derived polyhydroxyphenyl-γ-valerolactones were by far the main urinary catabolites, averaging 10 times greater concentratin than flavan-3-ol conjugates. The calculated bioavailability was equal to 39% and it is interesting to notice the great variability in urinary excretion of colonic metabolites among participants, probably related to differences in their own colonic microflora.Conclusion: This study demonstrates that green tea catechins are more bioavailable than previously observed when colonic ring fission metabolites are taken into consideration. Regular consumption of ready-to-drink green tea containing flavan-3-ols allows a non-marginal exposure of the human body to these catabolites, somehow justifying the numerous beneficial actions described as linked to green tea intake.

Fatty acid–binding protein-2 genotype influences lipid and lipoprotein response to eicosapentaenoic acid supplementation in hypertriglyceridemic subjects - Corrected Proof

2010-01-18

Abstract: Objective: The blood lipid-lowering effects of eicosapentaenoic acid (EPA) on hypertriglyceridemic subjects with different fatty acid–binding protein-2 (FABP2) genotypes have not, to our knowledge, been previously studied.Methods: Twenty-three FABP2 Ala54 and 23 Thr54 carriers with hypertriglyceridemia (triacylglycerol level >200mg/dL) were enrolled in this study. Participants took 2g of pure EPA daily for 8 wk. Fasting blood lipid and lipoprotein profiles were determined and changes from baseline were measured.Results: Blood lipids and lipoprotein responses of the FABP2 genotypes differed after EPA supplementation. Changes from baseline for triacylglycerol (19.2% decrease for Ala54 and 60.5% for Thr54, P<0.001), very low-density lipoprotein (20.0% decrease for Ala54 and 60.5% for Thr54, P<0.001), apolipoprotein CIII (22.8% decrease for Ala54 and 36.4% for Thr54, P<0.01), and high-density lipoprotein cholesterol (17.6% increase for Ala54 and 30.7% for Thr54, P<0.01) differed significantly between the two carrier groups. However, changes in total cholesterol, low-density lipoprotein cholesterol, and apolipoprotein B were not significant. EPA supplementation increased plasma EPA in Ala54 and Thr54 carriers. Although EPA supplementation increased the level of plasma EPA in both carrier groups, this effect was more pronounced in the Thr54 carriers.Conclusion: Therefore, EPA consumption has more favorable effects on blood lipids of hypertriglyceridemics with Thr54 genotype rather than those with Ala54. The level of plasma EPA increases after EPA supplementation. Because the FABP2 Thr54 polymorphism appears to be prevalent in hypertriglyceridemic subjects, increasing EPA intake in these subjects could be an effective strategy for reducing blood triacylglycerol concentration.

Nutritional status assessed by the Patient-Generated Subjective Global Assessment (PG-SGA) is associated with qualities of diet and life in Korean cerebral infarction patients - Corrected Proof

Hyun Jung Lim, Ryowon Choue — 2010-01-18

Abstract: Objective: Assessment of the nutritional status of patients with cerebral infarction (CI) is important because their nutritional status influences disease outcome. The purpose of this study was to assess the nutritional status of patients with CI using the scored Patient-Generated Subjective Global Assessment (PG-SGA) and to investigate the relation of the quality of their diet and life with their nutritional status.Methods: Seventy-three patients with CI were recruited from Kyung Hee University Oriental Medical Center in Seoul, Korea, from May to July 2007. The subjects' PG-SGA, dietary quality (Dietary Diversity Score, Dietary Variety Score, and Diet Quality Index–International), and quality of life (Stroke-Specific Quality of Life, modified Barthel Index, and Beck Depression Inventory) were investigated.Results: The patients were classified by PG-SGA categories as well nourished (26.0%), moderately malnourished (49.3%), or severely malnourished (24.7%). Quality of diet assessed by the Dietary Diversity Score and Dietary Variety Score was significantly lower in severely malnourished patients (P < 0.001). The overall dietary quality expressed by the Diet Quality Index–International was significantly greater in the well-nourished group, followed by the moderately malnourished and severely malnourished groups. Quality of life assessed by the Stroke-Specific Quality of Life and modified Barthel Index was significantly lower in the malnourished group (P < 0.05). Quality of diet (P < 0.001) and life (P < 0.05) in patients with CI were significantly correlated with their nutritional status.Conclusion: The PG-SGA is a useful nutritional assessment tool for patients with CI with stable vital signs. When patients with CI were categorized according to their PG-SGA score, well-nourished patients demonstrated better diet quality and better quality of life.

Three targets of branched-chain amino acid supplementation in the treatment of liver disease - Corrected Proof

Milan Holecek — 2010-01-13

Abstract: The article explains the pathogenesis of disturbances in branched-chain amino acid (BCAA; valine, leucine, and isoleucine) and protein metabolism in various forms of hepatic injury and it is suggested that the main cause of decrease in plasma BCAA concentration in liver cirrhosis is hyperammonemia. Three possible targets of BCAA supplementation in hepatic disease are suggested: (1) hepatic encephalopathy, (2) liver regeneration, and (3) hepatic cachexia. The BCAA may ameliorate hepatic encephalopathy by promoting ammonia detoxification, correction of the plasma amino acid imbalance, and by reduced brain influx of aromatic amino acids. The influence of BCAA supplementation on hepatic encephalopathy could be more effective in chronic hepatic injury with hyperammonemia and low concentrations of BCAA in blood than in acute hepatic illness, where hyperaminoacidemia frequently develops. The favorable effect of BCAA on liver regeneration and nutritional state of the body is related to their stimulatory effect on protein synthesis, secretion of hepatocyte growth factor, glutamine production and inhibitory effect on proteolysis. Presumably the beneficial effect of BCAA on hepatic cachexia is significant in compensated liver disease with decreased plasma BCAA concentrations, whereas it is less pronounced in hepatic diseases with inflammatory complications and enhanced protein turnover. It is concluded that specific benefits associated with BCAA supplementation depend significantly on the type of liver disease and on the presence of inflammatory reaction. An important task for clinical research is to identify groups of patients for whom BCAA treatment can significantly improve the health-related quality of life and the prognosis of hepatic disease.

Effects of different arginine concentrations on angiogenic protein production induced by HeLa cells - Corrected Proof

2010-01-13

Abstract: Objectives: This in vitro study investigated the effects of different arginine (Arg) concentrations on angiogenic protein expressions of HeLa cells and endothelial cells (ECs) after stimulation. In addition, an inducible nitric oxide (iNO) synthase inhibitor (1400W) was used to investigate the possible role of iNO in angiogenesis.Methods: Endothelial cells and HeLa cells were treated with different concentrations of Arg and 1400W: Arg 0, 50, 100, and 1000 μmol/L; Arg 100 μmol/L+1400W 10 μmol/L; and Arg 1000 μmol/L+1400W 10 μmol/L for 24h. Then, ECs and HeLa cells were cocultured for 2h, and the supernatant in the transwell was collected for analysis of angiogenic protein secreted. The expression of CD51/CD61 by ECs was also analyzed.Results: The productions of vascular endothelial growth factor, basic fibroblast growth factor, prostaglandin E2, and matrix metalloproteinase-2 were higher with Arg 100 and 1000 μmol/L than with Arg 0 and 50 μmol/L Arg, and this was consistent with the expression of CD51/CD61 by ECs. Inhibition of iNO production resulted in lower angiogenic protein expressions comparable with groups with low Arg administration.Conclusion: The findings of this study suggest that Arg administration at levels similar to or higher than physiologic concentrations enhance the production of angiogenic protein and iNO may partly play a role in promoting angiogenesis in the presence of HeLa cells.

Hypothesis: Muscular glutamine deficiency in sepsis—A necessary step for a hibernation-like state? - Corrected Proof

Erich Roth, Rudolf Oehler — 2010-01-13

Abstract: Glutamine depletion in skeletal muscle of severely ill patients is an outstanding metabolic marker related to acute skeletal muscle wasting. To date it is unclear why intracellular glutamine concentrations are lowered in skeletal muscle to such an extent when simultaneously muscular glutamine synthesis and release are stimulated. This essay introduces a hypothesis that intracellular glutamine deficiency is part of a metabolic program maintaining cell integrity. This program seems to resemble short-term hibernation, which can be observed in various mammalian species during periods of starvation. Interestingly, even in septic patients who do not survive, there are no signs of apoptosis or necrosis in affected organs. Therefore, in severe illness evolutionarily conserved energy saving programs may be switched on for protecting the organs in a mode reminiscent of hibernation. This would explain the low energy expenditure as described for septic patients and the limited success of nutrition in avoiding skeletal muscle atrophy in sepsis.

Neighborhood socioeconomic status in relation to dietary intake and insulin resistance syndrome in female Japanese dietetic students - Corrected Proof

2010-01-11

Abstract: Objective: An increasing number of studies in Western countries have shown that living in a socioeconomically disadvantaged neighborhood is associated with unfavorable dietary intake patterns and health status. However, information on such neighborhood socioeconomic differences in diet and health among different cultural settings, including Japan, is limited. This cross-sectional study examined the association of neighborhood socioeconomic status (SES) with dietary intake and a summary score of the insulin resistance syndrome (IRS) in a group of young Japanese women.Methods: Subjects were 1081 female Japanese dietetic students aged 18 to 22 y residing in 295 municipalities in Japan. Neighborhood SES index was defined by seven municipal-level variables, namely unemployment, household overcrowding, poverty, education, income, home ownership, and vulnerable group, with an increasing index signifying increasing neighborhood socioeconomic disadvantage. Dietary intake was estimated using a validated, comprehensive self-administered diet-history questionnaire. Measurements of body mass index, systolic blood pressure, fasting high-density lipoprotein cholesterol, triacylglycerol, glucose, and insulin were combined into an IRS score, with an increasing score signifying increasing levels of components of the IRS.Results: Neighborhood SES index was not associated with most of the dietary variables, body mass index, high-density lipoprotein cholesterol, triacylglycerol, or glucose. However, neighborhood SES index was significantly positively associated with systolic blood pressure, insulin, and IRS score, after adjustment for potential confounding or mediating factors, including household SES, dietary, and lifestyle factors.Conclusion: Neighborhood socioeconomic disadvantage was associated with unfavorable profiles of the IRS score, but not dietary intake, in a group of young Japanese women.

Perioperative metabolic changes in patients undergoing cardiac surgery - Corrected Proof

Stephan M. Jakob, Zeno Stanga — 2010-01-06

Abstract: Perioperative metabolic changes in cardiac surgical patients are not only induced by tissue injury and extracorporeal circulation per se: the systemic inflammatory response to surgical trauma and extracorporeal circulation, perioperative hypothermia, cardiovascular and neuroendocrine responses, and drugs and blood products used to maintain cardiovascular function and anesthesia contribute to varying degrees. The pathophysiologic changes include increased oxygen consumption and energy expenditure; increased secretion of adrenocorticotrophic hormone, cortisol, epinephrine, norepinephrine, insulin, and growth hormone; and decreased total tri-iodothyronine levels. Easily measurable metabolic consequences of these changes include hyperglycemia, hyperlactatemia, increased aspartate, glutamate and free fatty acid concentrations, hypokalemia, increased production of inflammatory cytokines, and increased consumption of complement and adhesion molecules. Nutritional risk before elective cardiac surgery—defined as preoperative unintended pathologic weight loss/low amount of food intake in the preceding week or low body mass index—is related to adverse postoperative outcome. Improvements in surgical techniques, anesthesia, and perioperative management have been designed to minimize the stressful stimulus to catabolism, thereby slowing the wasting process to the point where much less nutrition is required to meet metabolic requirements. Early nutrition in cardiac surgery is safe and well tolerated.

Association of glycemic load with cardiovascular disease risk factors: The Women's Health Initiative Observational Study - Corrected Proof

2010-01-06

Abstract: Objective: Associations between dietary glycemic load (GL) and cardiovascular disease risk factors, including plasma lipoprotein/lipid levels, blood pressure, and glucose metabolism factors, in the Women's Health Initiative Observational Study were examined.Methods: A random sample of 878 Observational Study participants (postmenopausal women 50–79 y of age) with baseline blood measurements (647 white, 104 black, 127 Hispanic) was included. Dietary GL was estimated from baseline food-frequency questionnaires, which assessed dietary intake over the previous 3 mo. At the baseline visit, participants completed demographic and health habit questionnaires, fasting blood samples were collected, anthropometric measurements were completed, and blood pressure was assessed.Results: In all participants combined, GL was inversely associated with high-density lipoprotein cholesterol (P for trend = 0.004) and positively associated with log10-transformed triacylglycerols (P = 0.008). Although there were no statistically significant interactions of race/ethnicity with associations between GL and cardiovascular disease risk factors, stratified results were suggestive, showing that GL was positively associated with total cholesterol (P = 0.018) and low-density lipoprotein cholesterol (P = 0.038) in Hispanics. In white subjects, there was a trend of reduced high-density lipoprotein cholesterol with higher GL (P = 0.003), whereas GL was positively associated with log10-transformed triacylglycerols (P = 0.015). Associations between GL and high-density lipoprotein cholesterol and between GL and triacylglycerols also differed by body mass index, although the interactions were not statistically significant.Conclusion: Among these generally healthy postmenopausal women, GL was associated with high-density lipoprotein cholesterol and triacylglycerols. Suggestive effects of race/ethnicity and body mass index on these associations need to be confirmed in larger studies.

Height prediction formula for middle-aged (30–55 y) Caucasians - Corrected Proof

Emanuele Cereda, Simona Bertoli, Alberto Battezzati — 2009-12-28

Abstract: Objective: Stature is essential for nutritional assessment but direct measurement is not possible in bed-ridden patients. Height prediction models have been developed for elderly persons but none is available for middle-aged people. We aimed to validate new equations for height prediction in middle-aged adults.Methods: Middle-aged (30–55 y) adults (n = 635, 316 men, 319 women) were studied for anthropometry (weight, standing height, knee height, and tibia length) and body composition (fat-free mass by impedance). The effect of estimated height on the derivation of body mass index and surface area, fat-free mass, and resting energy expenditure was evaluated. Multiple regressions analyzed the covariates in stature prediction. The best model was selected according to the highest R2 value and the lowest root mean square error.Results: We obtained a model valid for men and women that included age, knee height, and gender (R2 = 0.89, root mean square error = 3.2 cm, limits of agreement −6.1 to 6.5 cm). The use of estimated height in the calculation of body mass index, body surface area, fat-free mass, and REE produced acceptable biases. Application of the model to a control sample resulted in pure errors comparable to root mean square errors of the validation sample. In addition, the use of nationally representative models, introduced for elderly persons by Chumlea et al. (J Am Diet Assoc 1998;98:137–42), appeared to produce similar but slightly higher biases in both sexes.Conclusion: In middle-aged Caucasians, height can be estimated with acceptable accuracy by the model proposed in this report. The derivation of body mass index, body surface area, fat-free mass, and resting energy expenditure by this estimate is accurate. Nevertheless, in the absence of more accurate age- and race-specific prediction models, the use of equations by Chumlea et al. should always be considered.

Study of lymphocyte subpopulations in bone marrow in a model of protein–energy malnutrition - Corrected Proof

2009-12-28

Abstract: Objective: Protein–energy malnutrition (PEM) is an important public health problem affecting millions of people worldwide. Hematopoietic tissue requires a high nutrient supply, and a reduction in leukocytes, especially lymphocytes, suggests that some nutritional deficiencies might be altering bone marrow function and decreasing its ability to produce lymphocytes. In this study, we evaluated the effect that PEM has on lymphocyte subtypes and the cell cycle of CD5+ cells.Methods: Swiss mice were subjected to PEM using a low-protein diet containing 4% protein. When the experimental group had lost about 20% of their original body weight, we collected blood and bone marrow cells and evaluated the hemogram, the myelogram, bone marrow lymphoid markers using flow cytometry, and the cell cycle in CD5+ bone marrow.Results: Malnourished animals presented anemia, reticulocytopenia, and leukopenia with lymphopenia. The bone marrow was hypocellular, and flow cytometric analyses of bone marrow cells showed cells that were CD45+ (91.2%), CD2+ (84.9%), CD5+ (37.3%), CD3+ (23.5%), CD19+ (43.3%), CD22+ (34.7%), CD19+/CD2+ (51.2%), CD19+/CD3+ (24.0%), CD19+/CD5+ (13.2%), CD22+/CD2+ (40.1%), CD22+/CD3+ (30.3%), and CD22+/CD5+ (1.1%) in malnourished animals and CD45+ (97.5%), CD2+ (42.9%), CD5+ (91.5%), CD3+ (92.0%), CD19+ (52.0%), CD22+ (75.6%), CD19+/CD2+ (62.0%), CD19+/CD3+ (55.4%), CD19+/CD5+ (6.7%), CD22+/CD2+ (70.3%), CD22+/CD3+ (55.9%), and CD22+/CD5+ (8.4%) in control animals. Malnourished animals also presented more CD5+ cells in the G0 phase of cell cycle development.Conclusion: Malnourished animals presented bone marrow hypoplasia, maturation interruption, prominent lymphopenia with depletion in the lymphoid lineage, and changes in cellular development. We suggest that these changes are some of the primary causes of lymphopenia in cases of PEM and partly explain the increase in susceptibility to infections found in malnourished individuals.

A 4-year survey of the activity of a malnutrition task force in an Italian research hospital - Corrected Proof

2009-12-28

Abstract: Objective: The proper management of nutritional support remains a challenging task in many Western hospitals. This study aimed at reporting a 4-y survey on the centralized management of nutritional support by a malnutrition task force in an Italian research hospital.Methods: The requests for nutritional supports, the number of patients treated with enteral nutrition in the medical and surgical units, and the number of home artificial nutritional support activated were recorded from 2005 to 2008.Results: The median number of first and follow-up visits per month significantly increased from 16 (25th–75th percentiles 13–26) in 2005 to 74 (25th–75th percentiles 69–82) in 2008 (P < 0.001) and from 56 (25th–75th percentiles 42–82) in 2005 to 101 (25th–75th percentiles 90–120) in 2008 (P = 0.001), respectively. This trend was observed also in the number of patients treated with enteral nutrition (from 95 in 2004 to 190 in 2008) and in those on home artificial nutritional support (from 25 in 2004 to 65 in 2008), whereas the number of parenteral nutrition bags produced remained substantially stable.Conclusion: The centralized management of nutritional support is a successful strategy, which provides the appropriate prescription of artificial nutrition during hospitalization and at discharge. Multidisciplinary nutrition support teams or task forces should be created in every hospital.

Methionine-deficient diet induces post-transcriptional downregulation of cystathionine β-synthase - Corrected Proof

2009-12-28

Abstract: Objective: Elevated plasma total homocysteine (tHcy) is a risk factor for a variety of human diseases. Homocysteine is formed from methionine and has two primary metabolic fates: remethylation to form methionine or commitment to the transsulfuration pathway by the action of cystathionine β-synthase (CBS). We have examined the metabolic response in mice of a shift from a methionine-replete to a methionine-free diet.Methods and results: We found that shifting 3-mo-old C57BL6 mice to a methionine-free diet caused a transient increase in tHcy and an increase in the tHcy/methionine ratio. Because CBS is a key regulator of tHcy, we examined CBS protein levels and found that within 3 d on the methionine-deficient diet, animals had a 50% reduction in the levels of liver CBS protein and enzyme activity. Examination of CBS mRNA and studies of transgenic animals that express CBS from a heterologous promoter indicated that this reduction is occurring post-transcriptionally. Loss of CBS protein was unrelated to intracellular levels of S-adenosylmethionine, a known regulator of CBS activity and stability.Conclusion: Our results imply that methionine deprivation induces a metabolic state in which methionine is effectively conserved in tissue by shutdown of the transsulfuration pathway by an S-adenosylmethionine–independent mechanism that signals a rapid downregulation of CBS protein.

Intranasal insulin: From nose to brain - Corrected Proof

R.I. Henkin — 2009-12-21

Abstract: Background: Intranasal insulin has proven useful to control hyperglycemia in diabetics but its mechanism of action has not been well defined. We attempted to understand several aspects of human insulin metabolism by measurement of and interaction of insulin and its associated moieties in nasal mucus, saliva and blood plasma under various physiological and pathological conditions.Methods: Insulin, insulin receptors, insulin-like growth factor 1 (IGF1) and insulin-like growth receptor 3 (IGFR3) were measured in nasal mucus, saliva and blood plasma in normal subjects, in thin and obese subjects and in diabetics under fasting and fed conditions.Results: There are complex relationships among each of these moieties in each biological fluid. Insulin and its associated moieties are present in both nasal mucus and saliva. These moieties in nasal mucus and saliva report on physiological and pathological changes in glucose metabolism as do these moieties in plasma. Indeed, insulin and its associated moieties in nasal mucus may offer specific data on how insulin enters the brain and thereby play essential roles in control of insulin metabolism.Interpretation: These data support the concept that insulin is synthesized not only in parotid glands but also in nasal serous glands. They also support the concept that insulin enters the brain following intranasal administration either 1) by direct entry through the cribriform plate, along the olfactory nerves and into brain parenchyma, 2) by entry through specific receptors in blood-brain barrier and thereby into the brain or 3) some combination of 1) and 2). Conversely, data also show that insulin introduced directly into the brain is secreted out of brain into the peripheral circulation. Data in this study demonstrate for the first time that insulin and its associated moieties are present not only in saliva but also in nasal mucus. How these complex relationships among nasal mucus, saliva and plasma occur are unclear but results demonstrate these relationships play separate yet interrelated roles in physiology and pathology of human insulin metabolism.

Effects of fruit consumption on body mass index and weight loss in a sample of overweight and obese dieters enrolled in a weight-loss intervention trial - Corrected Proof

Kerstin E.E. Schroder — 2009-12-21

Abstract: Objective: Fruit and vegetable consumption is an important part of a healthy diet and assumed to aid in the reduction of energy intake and body weight. Fruits and vegetables may display differential effects on weight and weight loss; however, the effects of the two food groups have rarely been investigated separately.Methods: The present study focused on the effects of fruit consumption on body weight and weight loss in a sample of 77 overweight and obese dieters enrolled in an intervention program. Food consumption was assessed at baseline by food diaries and after the introduction of nutrition software through electronic food records. Body weight and additional physiologic outcomes were assessed three times, once before the intervention and again at the 3- and 6-mo follow-ups.Results: Vegetable and fruit consumption differed in their associations with body weight and weight loss. Although vegetable consumption increased as a result of the intervention (P<0.01), fruit consumption did not. However, only fruit consumption was associated with body mass index, showing an inverse relation with body weight in cross-sectional and longitudinal analyses (r=−0.27 to −0.44). The relation between fruit consumption and body weight remained significant after controlling for age, gender, physical activity level, and daily macronutrient consumption (ΔR2=0.06–0.13). Further, increases in fruit consumption were associated with subsequent weight loss, controlling for the same covariates (ΔR2=0.05–0.07).Conclusion: The results indicate unique contributions of fruit consumption to the management of body weight and indicate that a separation of effects for fruit and vegetable food groups may be warranted.

Effect of 6-month nutritional intervention on non-alcoholic fatty liver disease - Corrected Proof

2009-12-21

Abstract: Objective: We evaluated the effect of diet therapy as exclusive treatment on insulin resistance, biochemical parameters of metabolic syndrome, and degree of hepatic steatosis in patients with non-alcoholic fatty liver disease.Methods: Thirty-one patients with non-alcoholic fatty liver disease received a diet with a reduction of 500 to 1000cal/d, containing 15% protein, 55% carbohydrates, and 30% fat, for 6 mo. At entry and 6 mo after dietary instructions, degrees of hepatic steatosis and visceral obesity were assessed by computed tomography; serum aspartate aminotransferase, alanine aminotransferase, γ-glutamyl transferase, glucose, triacylglycerols, and high-density lipoprotein cholesterol were measured by automated methods. Body mass index, waist circumference, waist-to-hip ratio, and food intake (7-d diary) were also evaluated. At the end of follow-up, the patients were classified as adherent or non-adherent to treatment according to a weight loss of more or less than 5% of initial body weight, respectively.Results: Seventeen patients were classified as adherent (group 1) and 14 as non-adherent (group 2). Group 2 only presented a significant reduction in body mass index and waist circumference. In contrast, in group 1, in addition to significant improvement of all anthropometric parameters, a significant reduction was observed in alanine aminotransferase and γ-glutamyl transferase levels, homeostasis model assessment for insulin resistance, visceral fat and tomographic liver density, together with an increase in serum high-density lipoprotein cholesterol levels. These patients presented a significant decrease in total energy intake and in total and saturated fats.Conclusion: Nutritional intervention as exclusive treatment, with a loss of at least 5% of initial weight, is effective in the treatment of non-alcoholic fatty liver disease.

Diet supplementation with acai (Euterpe oleracea Mart.) pulp improves biomarkers of oxidative stress and the serum lipid profile in rats - Corrected Proof

2009-12-21

Abstract: Objective: We investigated the antioxidant potential and hypocholesterolemic effects of acai (Euterpe oleracea Mart.) pulp ingestion in rats fed a standard or hypercholesterolemic diet.Methods: Female Fischer rats were fed a standard AIN-93 M diet (control) or a hypercholesterolemic diet that contained 25% soy oil and 1% cholesterol. The test diet was supplemented with 2% acai pulp (dry wt/wt) for control (group CA) and hypercholesterolemic rats (group HA) for 6 wk. At the end of the experimental period, rats were sacrificed and the blood and livers were collected. To evaluate the effect of acai consumption, levels of protein carbonyl and sulfhydryl groups, superoxide dismutase and paraoxonase activities, and lipid profiles of the sera were measured.Results: Animals that were fed the hypercholesterolemic diet presented increased levels of total and non–high-density lipoprotein cholesterol and decreased levels of high-density lipoprotein cholesterol. Supplementing the diet of this group with acai caused a hypocholesterolemic effect by reducing total and non–high-density lipoprotein cholesterol. Serum levels of carbonyl proteins and total, free, and protein sulfhydryl groups were reduced by acai ingestion in animals receiving the standard or hypercholesterolemic diet. Acai supplementation induced a significant reduction in superoxide dismutase activity only in the hypercholesterolemic rats, indicating an association between diet and acai treatment. Also, acai supplementation increased paraoxonase activity in the CA and HA groups.Conclusion: These results suggest that the consumption of acai improves antioxidant status and has a hypocholesterolemic effect in an animal model of dietary-induced hypercholesterolemia.

Estimation of protein loss from wound fluid in older patients with severe pressure ulcers - Corrected Proof

2009-12-21

Abstract: Objective: Protein loss from wound fluid is usually recognized as one of the factors contributing to the deterioration of the nutritional status in older patients with severe pressure ulcers. We quantified the protein loss owing to pressure ulcers and investigated associations with wound-related factors and nutritional status.Methods: This cross-sectional study included 25 patients (≥60 y) from 10 institutions, with full-thickness pressure ulcers. Wound fluid was collected once after accumulating beneath a film dressing. The amount of protein loss per day was estimated by the volume of wound fluid per hour and the total protein concentration in the wound fluid. Wound evaluations and nutritional assessments were performed. Correlations between variables were obtained using Spearman's rank correlation.Results: The median age of the patients was 79 y (range 61–100), and median body mass index was 19.6kg/m2 (12.2–24.9). The median amount of protein loss was 0.2g/d (0.04–2.1), which corresponded to 0.01g · kg−1 · d−1 (<0.01–0.04) and 0.6% (0.1–13.8) of protein intake. Four wounds characterized as infected or surgically debrided lost 1.5–2.1g of protein per day, which was substantially higher than other wounds lost. Protein loss was correlated with wound severity including area, depth, the wound severity score, and infectious markers (all Ps<0.05), but not with body mass index or arm muscle circumference (P>0.05).Conclusion: The amount of protein loss could be small and thus may not be related directly to nutritional status, although it increased as the wound became more severe.

Effects of different ratios of monounsaturated and polyunsaturated fatty acids to saturated fatty acids on regulating body fat deposition in hamsters - Corrected Proof

Fang-Hsuean Liao, Tsan-Hon Liou, Ming-Jer Shieh, Yi-Wen Chien — 2009-12-21

Abstract: Objective: Effects of monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid consumption on regulating body fat accumulation and body weight gain are controversial between animal and human studies.Methods: We designed a 2 × 2 factorial study, with two levels of MUFAs (60% and 30%) and two levels of polyunsaturated-to-saturated fatty acid (P/S) ratio (5 and 3) to prepare four kinds of experimental oils consisting of 60% MUFAs with a high or low P/S ratio (HMHR or HMLR, respectively) or 30% MUFAs with a high or low P/S ratio (LMHR or LMLR, respectively). Thirty-two male golden Syrian hamsters were randomly divided into four groups and fed the experimental diets containing 15% (w/w) fat for 12 wk.Results: No difference was observed in the mean daily food intake. Hamsters fed the LMLR diet had increased weight gain, epididymal and retroperitoneal white adipose tissues, plasma non-esterified fatty acids, insulin, hepatic acetyl coenzyme A carboxylase and malic enzyme activities, and mRNA expressions of peroxisome proliferator-activated receptor-α and sterol regulatory element-binding protein-1c among all groups (P < 0.05). Hamsters fed the HMHR diet had lower plasma insulin levels and hepatic acetyl coenzyme A carboxylase activities among groups (P < 0.05) and elevated hepatic acyl coenzyme A oxidase and carnitine palmitoyltransferase-I activities compared with those fed the LMLR diet (P < 0.05).Conclusion: Hamsters fed the LMLR diet had increased weight gain and body fat accumulation, whereas the HMHR diet appeared to be beneficial in preventing white adipose tissue accumulation by decreasing plasma insulin levels and increasing hepatic lipolytic enzyme activities involved in β-oxidation.

Obesity: Genes, brain, gut, and environment - Corrected Proof

Undurti N. Das — 2009-12-21

Abstract: Obesity, which is assuming alarming proportions, has been attributed to genetic factors, hypothalamic dysfunction, and intestinal gut bacteria and an increase in the consumption of energy-dense food. Obesity predisposes to the development of type 2 diabetes mellitus, hypertension, coronary heart disease, and certain forms of cancer. Recent studies have shown that the intestinal bacteria in obese humans and mice differ from those in lean that could trigger a low-grade systemic inflammation. Consumption of a calorie-dense diet that initiates and perpetuates obesity could be due to failure of homeostatic mechanisms that regulate appetite, food consumption, and energy balance. Hypothalamic factors that regulate energy needs of the body, control appetite and satiety, and gut bacteria that participate in food digestion play a critical role in the onset of obesity. Incretins, cholecystokinin, brain-derived neurotrophic factor, leptin, long-chain fatty acid coenzyme A, endocannabinoids and vagal neurotransmitter acetylcholine play a role in the regulation of energy intake, glucose homeostasis, insulin secretion, and pathobiology of obesity and type 2 diabetes mellitus. Thus, there is a cross-talk among the gut, liver, pancreas, adipose tissue, and hypothalamus. Based on these evidences, it is clear that management of obesity needs a multifactorial approach.

Enteral nutrition for severe malnutrition in chronic intestinal pseudo-obstruction - Corrected Proof

Jaya Benjamin, Namrata Singh, Govind K. Makharia — 2009-12-17

Abstract: Objective: Chronic intestinal pseudo-obstruction (CIPO) is a rare intestinal motility disorder. A prolonged avoidance of food due to fear of aggravation of postprandial symptoms leads to severe malnutrition. We report a case of a 21 y old man who was diagnosed as CIPO with a history of recurrent intestinal colic and obstructive symptoms, slow transit type of constipation, bilateral hydronephrosis (non-obstructive), motor dysphagia without any evidence of demonstrable mechanical obstruction. Our aim was to keep his post prandial symptoms to a minimum and nutritionally build him up with enteral nutrition (EN).Methods: He had life threatening malnutrition (BMI of 11 kg/m2) and significant postprandial distension with an intake more than 100 ml, compromising the quality of life. In view of a normal absorptive function of the gut, TPN was ruled out and the patient was treated with enteral nutrition (oral & tube) only. The EN regimen followed was ad libitum oral intake along with nocturnal NG tube feeding. Initially a full strength semi-elemental formula at 50 ml/hour was given, later shifted to polymeric formula at 100 ml/hour. Serum levels of magnesium, phosphate and potassium were regularly monitored to prevent refeeding syndrome. He ws constantly motivated, counseled and monitored.Result: With a gradual increase in the intake from 300 Kcal to 1400 Kcal he was discharged. Eight months from discharge he had a weight of 58 kg (BMI = 22.3 kg/m2), with resumption of normal activities and marked improvement in the quality of life.Conclusion: Carefully planned EN along with motivation, psychological support and regular monitoring are the keys to nutritional management in CIPO.

Influence of traumatic brain injury on potassium and phosphorus homeostasis in critically ill multiple trauma patients - Corrected Proof

2009-12-17

Abstract: Objective: The intent of this study was to ascertain whether multiple trauma patients with traumatic brain injury (TBI) had lower serum concentrations of potassium and phosphorus and required more aggressive supplementation than multiple trauma patients without TBI.Methods: Ventilator-dependent adult patients without renal impairment who were admitted to the trauma intensive care unit or neurosurgical intensive care unit and who received enteral nutrition were evaluated for the first 14 d after hospital admission. Patients were grouped according to the presence or absence of TBI. Target serum concentrations for potassium and phosphorus were 4 mEq/L and 4 mg/dL, respectively. Electrolyte repletion therapy was given according to the nutritional support service guidelines.Results: Fifty trauma patients (25 with and without TBI) were studied. Daily serum potassium concentrations were consistently lower for those with TBI (P ≤ 0.001), whereas the mean net potassium intake was greater (1.3 ± 0.5 versus 0.7 ± 0.3 mEq · kg−1 · d−1, respectively, P ≤ 0.001). Serial serum phosphorus concentrations were similar between groups (P = NS) except for a significantly lower serum phosphorus concentration for trauma patients with TBI on day 3 after hospital admission (2.5 ± 0.5 versus 2.9 ± 0.7 mg/dL, respectively, P ≤ 0.05). However, the mean net phosphorus intake was significantly greater for trauma patients with TBI (0.65 ± 0.25 versus 0.45 ± 0.17 mmol · kg−1 · d−1, P ≤ 0.001).Conclusion: Potassium and phosphorus requirements are greater for multiple trauma patients with TBI compared with those without TBI.

Effect of nutritional support team restructuring on the use of parenteral nutrition - Corrected Proof

Krishnan Sriram, Tissy Cyriac, Louis F. Fogg — 2009-12-17

Abstract: Objective: The inappropriate use of parenteral nutrition (PN) continues to be a problem, despite several decades of efforts to improve the situation. We restructured our existing nutritional support team employing methods involving the institution's systems and individual physician interaction and education. Our aim was to study the effects of these changes on the use of PN in our institution.Methods: Records of all non-critically ill patients seen by our nutritional support team for PN during 2003–2004 (phase I, before restructuring) and 2005–2006 (phase II) were reviewed. Patients were classified under “appropriate,” “inappropriate,” and “marginal” categories based on published guidelines. During phase II, a new committee was formed, policies and procedures were updated, educational activities were increased, emphasis was placed on evidence-based guidelines, and periodic bedside rounds with the team physicians were initiated. Communication with referring physicians was improved.Results: Three hundred three of 335 patients in phase I and 271 of 333 patients in phase II were eligible for inclusion in analysis. Appropriate PN increased from 71.3% to 83.4%; inappropriate PN decreased from 16.5% to 8.9% (P = 0.002).Conclusion: Restructuring of the nutritional support team improved the proper utilization of PN and decreased inappropriate use of PN in a public teaching hospital.

Effect of Brazil nut supplementation on the blood levels of selenium and glutathione peroxidase in hemodialysis patients - Corrected Proof

M.B. Stockler-Pinto, D. Mafra, N.E. Farage, G.T. Boaventura, S.M.F. Cozzolino — 2009-12-17

Abstract: Objective: In patients who have undergone hemodialysis, large amounts of reactive oxygen species (ROS) are produced and, at higher concentrations, ROS are thought to be involved in the pathogenesis of cardiovascular disease. It has been proposed that selenium (Se) may exert an antiatherogenic influence by reducing oxidative stress. The richest known food source of selenium is the Brazil nut (Bertholletia excelsa, family Lecythidaceae), found in the Amazon region. We evaluated the effect of Brazil nut supplementation on blood levels of Se and glutathione peroxidase (GSH-Px) activity in patients on hemodialysis.Methods: A total of 81 patients on hemodialysis (52.0±15.2 y old, average time on dialysis 82.3±91.4 mo, body mass index 24.9±4.4kg/m2) from the RenalCor and RenalVida Clinics in Rio de Janeiro, Brazil, were studied. All patients received one nut (around 5g, averaging 58.1μg Se/g) a day for 3 mo. The Se concentrations in the nuts and in plasma and erythrocytes were determined by atomic absorption spectrophotometry with hydride generation (Hitachi, Z-500). GSH-Px levels were measured using Randox commercial kits.Results: Plasma Se (18.8±17.4μg/L) and erythrocyte (72.4±37.9μg/L) levels were below the normal range before nut supplementation. After supplementation, the plasma level increased to 104.0±65.0μg/L and erythrocytes to 244.1±119.5μg/L (P<0.0001). The activity of GSH-Px also increased after supplementation, from 46.6±14.9 to 55.9±23.6 U/g of hemoglobin (P<0.0001). Before supplementation, 11% of patients had GSH-Px activity below the normal range (27.5–73.6 U/g of hemoglobin). After supplementation, all patients showed GSH-Px activity within the normal range.Conclusion: The data revealed that the investigated patients presented Se deficiency and that the consumption of only one Brazil nut a day (5g) during 3 mo was effective to increase the Se concentration and GSH-Px activity in these patients, thus improving their antioxidant status.

Metabolic origin of hypovitaminosis C in acutely hospitalized patients - Corrected Proof

Rebecca Evans-Olders, Shaun Eintracht, L. John Hoffer — 2009-12-17

Abstract: Objective: Recent studies have indicated a high prevalence of hypovitaminosis C in acutely hospitalized patients. It is unclear whether hypovitaminosis C in this setting represents deficiency or tissue redistribution of the vitamin as part of the acute-phase response.Methods: We administered vitamin C for 1 wk to acutely hospitalized, but not critically ill patients with hypovitaminosis C, on the assumption that a large increase in plasma and mononuclear leukocyte vitamin C concentrations, a decrease in metabolic markers of oxidative stress, or an improvement in psychologic mood state would implicate the initial condition as nutritional deficiency rather than tissue redistribution.Results: Vitamin C administration increased plasma and mononuclear leukocyte vitamin C concentrations from subnormal (16.3 ± 12.4 μmol/L and 6.5 ± 5.5 mmol/L, respectively) to normal (71.0 ± 30.9 μmol/L, P < 0.0001, and 8.2 ± 6.8 mmol/L, P < 0.015); the mood disturbance score improved by 33% (P < 0.008). There was no increase in plasma glutathione concentrations or a reduction in plasma or mononuclear leukocyte malondialdehyde concentrations. An inverse relation was observed between plasma C-reactive protein and plasma vitamin C concentrations (P = 0.006).Conclusion: Although associated with systemic inflammation, the metabolic features of hypovitaminosis C in acutely hospitalized, non-critically ill patients are more consistent with deficiency than with tissue redistribution.