Effect of citric pectin on beta-carotene bioavailability in rats

The effect of citric pectin on the bioavailability of synthetic beta-carotene was studied. Thirty Wistar rats were used, ten animals were sacrificed at the beginning of the experiment and remaining animals were divided into two groups and received the following diets for 30 days: control group (CG)--24 micrograms beta-carotene/g diet + 0% citric pectin; experimental group (EG)--24 micrograms beta-carotene/g diet + 7% citric pectin. Plasma and liver beta-carotene, vitamin A, and retinyl palmitate concentrations were determined by high-performance liquid chromatography (HPLC). Plasma retinol concentration was 1.42 +/- 0.36 mumol/L for CG and 1.10 +/- 0.24 mumol/L for EG (p = 0.1), and plasma beta-carotene concentration was 0.20 +/- 2.51 mumol/L for CG and 0.07 +/- 0.04 mumol/L for EG (p = 0.01). Only traces of retinyl palmitate were detected in CG and none in EG. Retinol did not differ significantly between groups CG and EG, while a significantly higher beta-carotene concentration was observed for CG. Liver concentrations of retinol (CG: 4.90 +/- 2.51 micrograms/g; EG: 2.68 +/- 1.12 micrograms/g), beta-carotene (CG: 0.98 +/- 0.28 microgram/g; EG: 0.11 +/- 0.06 microgram/g), and retinyl palmitate (CG: 95.47 +/- 45.13 micrograms/g, EG: 37.01 +/- 17.20 micrograms/g) differed significantly between groups (p < 0.05), with a lower concentration being observed for EG. We conclude that 7% citric pectin in the rat diet decreases the bioavailability of synthetic beta-carotene, reducing the liver reserves of vitamin A and beta-carotene.     

Bioactivity of beer and its influence on human metabolism

Extracted total phenols, flavanols and flavonoids were measured in beer samples and their quality as antioxidants was measured by two modified antioxidant methods: the 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonate) radical cation (ABTS * +) and the beta-carotene-linoleate model system (beta-carotene). It was found that the antioxidant potential of beer was well correlated with flavanols and flavonoids and was slightly lower with total polyphenols (R2 values from 0.8203 to 0.9393). Forty-two male non drinkers, hypercholesterolaemic volunteers ages 43-71 after coronary bypass surgery, were randomly divided into experimental (EG) and control (CG) groups, each of 21 participants. The antiatherosclerotic diet of the EG group was supplemented for 30 consecutive days with 330 ml beer per day. Could short-term beer consumption affect not only the risk factors of coronary atherosclerosis, but also the markers of this process: plasma albumin and its antioxidant activity? For this goal, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, plasma albumin and fibrinogen, and the antioxidant activity were determined. After the trial a significant improvement in the plasma lipid levels, and an increase in the plasma antioxidant and anticoagulant activities in patients of the EG group was registered. A parallel increase in the plasma albumin concentration and its antioxidant activity was observed. In conclusion, short-term beer consumption on the basis of the bioactivity of the beverage positively affects plasma lipid levels, plasma antioxidant and anticoagulant activities. The increase in the plasma albumin concentration and its antioxidant activity could be the markers of atherosclerosis status.     

A diet rich in dietary fiber from cocoa improves lipid profile and reduces malondialdehyde in hypercholesterolemic rats

OBJECTIVE: The potential hypolipidemic effect of a new cocoa product rich in dietary fiber (DF) naturally containing antioxidant polyphenols (cocoa fiber [CF]) was studied in a rat model of dietary-induced hypercholesterolemia. METHODS: For 3 wk animals were fed normal, cholesterol-free diets or diets supplemented with cholesterol to evoke hypercholesterolemia. Control diets contained 10% cellulose as DF, and test diets were supplemented with 165 g of CF per kilogram (providing 10% DF). Lipid profile, total antioxidant capacity, and malondialdehyde were measured in serum in addition to the activity of the antioxidant enzymes catalase, glutathione reductase, glutathione peroxidase, and superoxide dismutase and concentrations of glutathione and malondialdehyde in the liver. RESULTS: Hypercholesterolemia and hypertriglyceridemia were established as a consequence of the cholesterol-rich diets. CF showed an important hypolipidemic action, returning triacylglycerol levels in hypercholesterolemic animals to normal values. The hypocholesterolemic effect was also patent, reducing total and low-density lipoprotein cholesterol, yet basal values were not attained. Decreased lipid peroxidation in serum and liver as a consequence of CF intake was patent not only in hypercholesterolemic but also in normocholesterolemic animals. No apparent effects on serum total antioxidant capacity or on the activity of antioxidant enzymes and hepatic levels of glutathione were observed. These effects might be attributed to the high DF content of CF and to the natural presence of antioxidant polyphenols. CONCLUSION: The consumption of CF with a hypercholesterolemic diet improved the lipidemic profile and reduced lipid peroxidation, suggesting that CF might contribute to a reduction of cardiovascular risk.     

Palmitic and stearic acids similarly affect plasma lipoprotein metabolism in cynomolgus monkeys fed diets with adequate levels of linoleic acid

This study was designed to evaluate whether the exchange of specific saturated fatty acids [SFA; palmitic acid (16:0) for stearic acid (18:0)] would differentially affect plasma lipids and lipoproteins, when diets contained the currently recommended levels of total SFA, monounsaturated fatty acids and polyunsaturated fatty acids (PUFA). Ten male cynomolgus monkeys were fed one of two purified diets (using a cross-over design) enriched either in 16:0 (palmitic acid diet) or 18:0 (stearic acid diet). Both diets provided 30% of energy as fat (SFA/monounsaturated fatty acid/PUFA: 1/1/1). The palmitic acid and stearic acid diets were based on palm oil or cocoa butter (59% and 50% of the total fat, respectively). By adding different amounts of sunflower, safflower and olive oils, an effective exchange of 16:0 for 18:0 of approximately 5% of energy was achieved with all other fatty acids being held constant. Monkeys were rotated through two 10-wk feeding periods, during which time plasma lipids and in vivo lipoprotein metabolism (following the simultaneous injection of (131)I-LDL and (125)I- HDL were evaluated). Plasma triacyglycerol (0.40 +/- 0.03 vs. 0.37 +/- 0.03 mmol/L), plasma total cholesterol (3.59 +/- 0.18 vs. 3.39 +/- 0.23 mmol/L), HDL cholesterol (1.60 +/- 0.16 vs 1.53 +/- 0.16 mmol/L) and non-HDL cholesterol (2.02 +/- 0.26 vs. 1.86 +/- 0.23 mmol/L) concentrations did not differ when monkeys consumed the palmitic acid and stearic acid diets, respectively. Plasma lipoprotein compositional analyses revealed a higher cholesteryl ester content in the VLDL fraction isolated after consumption of the stearic acid diet (P < 0.10), as well as a larger VLDL particle diameter (16.3 +/- 1.7 nm vs. 13.8 +/- 3.6 nm; P < 0.05). Kinetic analyses revealed no significant differences in LDL or HDL transport parameters. These data suggest that when incorporated into diets following current guidelines, containing adequate PUFA, an exchange of 16:0 for 18:0, representing approximately 11 g/(d.10.46 mJ) [ approximately 11 g/(d.2500 kcal)] does not affect the plasma lipid profile and has minor effects on lipoprotein composition. Whether a similar effect would occur in humans under comparable dietary conditions remains to be established.     

ω-3多不饱和脂肪酸在老年胃癌病人术后肠外营养中的应用

目的: 研究在老年病人胃癌根治术后肠外营养(PN)中应用ω-3多不饱和脂肪酸(ω-3 PUFA)的作用. 方法: 将40例老年胃癌切除术后病人随机分为试验组和对照组,每组20例.对照组病人按低氮、低热量原则给予PN治疗,试验组加用ω-3 PUFA.比较两组病人营养指标、免疫指标、肝功能变化、炎性反应指标和并发症的发生率等. 结果: 试验组病人并发症的发生率为5%,对照组为20%,差异有显著性意义(P<0.05).术后经5 d的治疗,试验组病人PA水平、体液免疫和细胞免疫指标、IgA、IgG含量和CD4细胞均显著高于对照组(P<0.05,P<0.01).两组病人术后第1天IL-6、TNF-α和CRP水平均升高.第5天后,试验组IL-6、TNF-α和CRP显著低于对照组(P<0.05).对照组病人肝功指标明显升高,与试验组相比有显著性差异(P<0.05). 结论: ω-3 PUFA可通过阻断过度炎性反应、调节病人免疫功能和保护器官功能等作用,有利于老年胃癌病人术后的康复.     

Effect of simvastatin therapy on endothelial function of hypercholesteremic patients with syndrome X

INTRODUCTION: Cardiac syndrome X patients often have both reduced coronary circulation and impaired systemic endothelial function. AIMS: The aim of our study was to assess the effect of chronic statin therapy on exercise-induced "ischemic like" ST segment depression and on systemic endothelial function in cardiac syndrome X patients with hypercholesterolemia. PATIENTS/METHODS: In 25 hypercholesterolemic patients (15 males, mean age 55 +/- 3 years) with a normal coronary angiogram and positive exercise ECG test (> 0.1 mV ST segment depression) the flow mediated dilatation (FMD) was assessed by measuring the change in brachial artery diameter in response to hyperemic flow by vascular ultrasound. All patients were treated with 20 mg simvastatin in duration of 12 weeks. Following the treatment the exercise ECG and the vascular ultrasound studies were repeated. RESULTS: There was a significant decrease in total serum cholesterol level (baseline = 5.82 +/- 0.19 mmol/L vs. study end = 4.49 +/- 0.17 mmol/L, p < 0.01) and significant increase in the serum HDL level (baseline = 1.05 +/- 0.16 mmol/L vs. study end = 1.11 +/- 0.14 mmol/L, p < 0.01) following the statin treatment. Parallelly brachial artery FMD increased significantly (baseline = 3.97 +/- 0.91% vs. study end = 6.84 +/- 0.89%, p < 0.05). Responses to nitroglycerin were similar during the time course of the study. The ischemia free stress test time was also higher at the study end (baseline = 5.18 +/- 2.01 min vs. study end = 6.01 +/- 1.94 min, p < 0.001). CONCLUSIONS: The chronic statin therapy exerts beneficial effects both on systemic and coronary endothelial function in hypercholesterolemic patients with cardiac syndrome X.     

Bioactivity of beer and its influence on human metabolism

Extracted total phenols, flavanols and flavonoids were measured in beer samples and their quality as antioxidants was measured by two modified antioxidant methods: the 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonate) radical cation (ABTS ^?+) and the β-carotene-linoleate model system (β-carotene). It was found that the antioxidant potential of beer was well correlated with flavanols and flavonoids and was slightly lower with total polyphenols (R² values from 0.8203 to 0.9393). Forty-two male non drinkers, hypercholesterolaemic volunteers ages 43–71 after coronary bypass surgery, were randomly divided into experimental (EG) and control (CG) groups, each of 21 participants. The antiatherosclerotic diet of the EG group was supplemented for 30 consecutive days with 330 ml beer per day. Could short-term beer consumption affect not only the risk factors of coronary atherosclerosis, but also the markers of this process: plasma albumin and its antioxidant activity? For this goal, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, plasma albumin and fibrinogen, and the antioxidant activity were determined. After the trial a significant improvement in the plasma lipid levels, and an increase in the plasma antioxidant and anticoagulant activities in patients of the EG group was registered. A parallel increase in the plasma albumin concentration and its antioxidant activity was observed. In conclusion, short-term beer consumption on the basis of the bioactivity of the beverage positively affects plasma lipid levels, plasma antioxidant and anticoagulant activities. The increase in the plasma albumin concentration and its antioxidant activity could be the markers of atherosclerosis status.     

Targeted Physician Education Positively Affects Delivery of Nutrition Therapy and Patient Outcomes

Background: Malnutrition is a continuing epidemic among hospitalized patients. We hypothesize that targeted physician education should help reduce caloric deficits and improve patient outcomes. Materials and Methods: We performed a prospective trial of patients (n = 121) assigned to 1 of 2 trauma groups. The experimental group (EG) received targeted education consisting of strategies to increase delivery of early enteral nutrition. Strategies included early enteral access, avoidance of nil per os (NPO) and clear liquid diets (CLD), volume‐based feeding, early resumption of feeds postprocedure, and charting caloric deficits. The control group (CG) did not receive targeted education but was allowed to practice in a standard ad hoc fashion. Both groups were provided with dietitian recommendations on a multidisciplinary nutrition team per standard practice. Results: The EG received a higher percentage of measured goal calories (30.1 ± 18.5%, 22.1 ± 23.7%, P = .024) compared with the CG. Mean caloric deficit was not significantly different between groups (–6796 ± 4164 kcal vs ?8817 ± 7087 kcal, P = .305). CLD days per patient (0.1 ± 0.5 vs 0.6 ± 0.9), length of stay in the intensive care unit (3.5 ± 5.5 vs 5.2 ± 6.8 days), and duration of mechanical ventilation (1.6 ± 3.7 vs 2.8 ± 5.0 days) were all reduced in the EG compared with the CG (P < .05). EG patients had fewer nosocomial infections (10.6% vs 23.6%) and less organ failure (10.6% vs 18.2%) than did the CG, but these differences did not reach statistical significance. Conclusion: Implementation of specific educational strategies succeeded in greater delivery of nutrition therapy, which favorably affected patient care and outcomes.     

Plasma antioxidant capacity in response to diets high in soy or animal protein with or without isoflavones

BACKGROUND: Several clinical trials have suggested that soy intake decreases oxidative stress. Soy isoflavones have antioxidant properties in vitro, but results of supplementation in clinical trials are inconclusive. OBJECTIVE: The objective was to evaluate the independent effects of soy protein and soy-derived isoflavones on plasma antioxidant capacity and biomarkers of oxidative stress. DESIGN: Forty-two hypercholesterolemic (LDL cholesterol > 3.36 mmol/L) subjects aged >50 y were provided with each of 4 diets in random order in a crossover design. Diets varied in protein source (10% of energy, soy or animal) and isoflavone content (trace or 50 mg/1000 kcal) and were consumed for 42 d each. Plasma antioxidants, protein carbonyls, malondialdehyde, total antioxidant performance, LDL oxidizability, and urinary F(2)-isoprostanes were measured at the end of each dietary phase. RESULTS: Plasma antioxidant concentrations were not significantly different, regardless of dietary treatment, except for isoflavones, which were higher after isoflavone supplementation (P = 0.0001). Although plasma total antioxidant performance was 10% higher with soy protein intake, regardless of dietary isoflavones (P = 0.0003), soy protein did not significantly affect most individual markers of oxidative stress (LDL oxidizability, urinary F(2)-isoprostanes, malondialdehyde, or protein carbonyls in native plasma). However, soy protein was associated with modestly lower concentrations of protein carbonyls in oxidized plasma. There was no significant effect of isoflavones on LDL oxidation, urinary F(2)-isoprostanes, or protein carbonyl groups, although, paradoxically, the plasma malondialdehyde concentration was significantly higher after the isoflavone-rich diets (P = 0.04). CONCLUSIONS: Diets relatively high in soy protein or soy-derived isoflavones have little effect on plasma antioxidant capacity and biomarkers of oxidative stress.     

Behenic acid is a cholesterol-raising saturated fatty acid in humans

BACKGROUND: Dietary behenic acid (22:0) is poorly absorbed. Because of its low bioavailability compared with other fatty acids and because of its very long chain length, the effect of dietary behenic acid (behenate) on serum lipid concentrations in humans is assumed to be neutral. OBJECTIVE: The objective was to establish the cholesterol-raising potential of behenic acid by comparing the effects on lipid and lipoprotein concentrations of a specially formulated fat enriched with behenic acid with those of palm oil (rich in palmitic acid; 16:0) and high-oleic acid sunflower oil (rich in cis oleic acid; 18:1). DESIGN: In a randomized, crossover, metabolic-ward study, 7 mildly hypercholesterolemic men were fed 3 natural-food diets supplemented with behenate oil, palm oil, or high-oleic acid sunflower oil. Mean serum lipid and lipoprotein concentrations and plasma triacylglycerol fatty acid composition were determined from fasting blood drawn during the final 4 d of each 3-wk diet period. RESULTS: Behenate oil produced mean concentrations of total cholesterol (5.87+/-0.8 mmol/L) and LDL cholesterol (4.40+/-0.8 mmol/L) not significantly different from those produced by palm oil (5.84+/-0.7 and 4.42+/-0.7 mmol/L, respectively) but significantly higher than those produced by high-oleic acid sunflower oil (5.12+/-0.5 and 3.70+/-0.6 mmol/L, respectively). There were no significant differences in triacylglycerol or HDL-cholesterol concentrations. CONCLUSIONS: Despite its low bioavailability compared with oleic acid, behenic acid is a cholesterol-raising fatty acid in humans and is therefore not a suitable substitute for palmitic acid in manufactured triacylglycerols.     

Soy food consumption does not lower LDL cholesterol in either equol or nonequol producers

BACKGROUND: Health claims link soy protein (SP) consumption, through plasma cholesterol reduction, to a decreased risk of heart disease. Soy isoflavones (ISOs), particularly in individuals who produce equol, might also contribute to lipid lowering and thus reduce SP requirements. OBJECTIVE: The objective was to examine the contributions of SP, ISOs, and equol to the hypocholesterolemic effects of soy foods. DESIGN: Nonsoy consumers (33 men, 58 women) with a plasma total cholesterol (TChol) concentration >5.5 mmol/L participated in a double-blind, placebo-controlled, crossover intervention trial. The subjects consumed 3 diets for 6 wk each in random order, which consisted of foods providing a daily dose of 1) 24 g SP and 70-80 mg ISOs (diet S); 2) 12 g SP, 12 g dairy protein (DP), and 70-80 mg ISOs (diet SD); and 3) 24 g DP without ISOs (diet D). Fasting plasma TChol, LDL cholesterol, HDL cholesterol, and triglycerides (TGs) were measured after each diet. RESULTS: TChol was 3% lower with the S diet (-0.17 +/- 0.06 mmol/L; P < 0.05) than with the D diet, and TGs were 4% lower with both the S (-0.14 +/- 0.05 mmol/L; P < 0.05) and SD (-0.12 +/- 0.05 mmol/L; P < 0.05) diets. There were no significant effects on LDL cholesterol, HDL cholesterol, or the TChol:HDL cholesterol ratio. On the basis of urinary ISOs, 30 subjects were equol producers. Lipids were not affected significantly by equol production. CONCLUSIONS: Regular consumption of foods providing 24 g SP/d from ISOs had no significant effect on plasma LDL cholesterol in mildly hypercholesterolemic subjects, regardless of equol-producing status.     

Effects of severe protein restriction with ketoanalogues in advanced renal failure.

OBJECTIVE: To compare a severe protein restriction diet supplemented with ketoanalogues to a moderate protein restriction diet in order to limit glomerular filtration rate (GFR) decrease in an advanced renal insufficiency stage. DESIGN: Prospective randomised study conducted to compare a severe protein restriction diet (0.30 g/kg/day) supplemented with a preparation of ketoanalogues, hydroxyanalogues of aminoacids and aminoacids (Group A) to a moderate protein restriction diet (0.65 g/kg/day) (Group B). PATIENTS: 50 uremic patients included (25 in each group) with GFR is <20 mL/min/1.73m2. RESULTS: There were no statistically significant differences between the two dietary regimens for the renal survival. But uremia decreased significantly in Group A (22.7+/-5.2 to 18.5+/-6.7 mmol/L) and increased in Group B (26.8+/-9.0 to 34.9+/-9.9 mmol/L). Calcemia increased in Group A from 2.28+/-0.18 to 2.42+/-0.17 mmol/L, p<0.01 with a stable phosphoremia while calcemia decreased in Group B (2.33+/-0.18 to 2.25+/-0.17 mmol/L, p<0.05). At the end of the study, Group A was different from Group B for calcemia (2.42+/-0.17 vs. 2.25+/-0.17 mmol/L, p<0.01), phosphoremia (1.39+/-0.30 vs. 1.80+/-0.65 mmol/L, p<0.02), alkaline phosphatase (61.42+/-22.93 vs. 78.8+/-27.0, p<0.05) and parathormone plasma levels (2.71+/-1.55 vs. 5.91+/-1.41 ng/mL, p<0.001). COMMENTS: Compared to a moderate protein restriction (0.65 g/kg/day), a severe protein restriction (0.3 g/kg/day) supplemented by ketoanologues does not limit GFR decrease when GFR is below 20 mL/min/1.73m2, but improves phosphocalcic plasma parameters.     

Free fatty acids in exercising Arabian horses fed two common diets.

Four Arabian geldings were used in a randomized, repeated measure design to study the effect of two different diets on plasma free fatty acids at rest and during exercise. On each of four sampling days, two horses were fed one of two isoenergetic diets, either 100% corn or 100% alfalfa, at 22% of their estimated daily energy requirement. Two hours after the consumption of the diet, each horse participated in a submaximal standard exercise test consisting of three consecutive 10-min runs of increasing intensity at heart rates of 132, 140 and 147 beats/min, respectively. There were no significant (P greater than 0.05) differences between the two groups (corn-fed vs. alfalfa-fed) in pre-meal (0.554 +/- 0.031 vs. 0.629 +/- 0.033 mmol/L), post-meal (0.520 +/- 0.027 vs. 0.609 +/- 0.041 mmol/L), and basal (0.392 +/- 0.036 vs. 0.401 +/- 0.052 mmol/L) free fatty acid concentrations. However, free fatty acids were significantly higher in the horses fed alfalfa (0.608 +/- 0.038 mmol/L) rather than corn (0.484 +/- 0.031 mmol/L) during exercise.     

Biochemical antioxidant levels respond to supplementation with an enriched drink in frail elderly people

OBJECTIVE: To investigate whether a drink enriched with essential vitamins and minerals can improve biochemical status of enzymatic and non-enzymatic antioxidants in frail elderly people. METHODS: A six-month randomized, double blind, placebo controlled intervention study. Frail elderly people 65 years of age or older, with a body mass index (BMI) below 25 kg/m(2) and residing in a home for the elderly or in sheltered housing. Enriched (with essential vitamins and minerals in 30% to 150% of RDA and higher levels of antioxidants) drink (n = 28) or placebo (n = 27) to be taken twice a day in addition to the normal food consumed. Plasma levels of vitamin C, vitamin E, antioxidant capacity (TEAC), cysteine, uric acid and whole blood levels of total thiol and glutathione peroxidase (GSH-Px), dietary intake. RESULTS: Changes in vitamin E (16 +/- 2 vs. 2 +/- 1 mmol/L), vitamin C (37 +/- 5 vs. 1 +/- 5 mmol/L), TEAC (38 +/- 15 vs. -10 +/- 11 mmol/L Trolox eq) and cysteine (17 +/- 10 vs. 0.4 +/- 6 mmol/L) were significantly different between groups (p < 0.05). There was a trend towards significant changes in erythrocyte glutathione peroxidase (-0.2 +/- 3 vs. -10 +/- 7 U/mg Hb, p = 0.097). Baseline dietary intake of antioxidant vitamins was below 2/3 RDA for a substantial proportion (43% to 76%) of subjects. CONCLUSIONS: Supplementation with an enriched drink can raise plasma levels of enzymatic and non-enzymatic antioxidants in frail elderly people.     

Oat bran lowers plasma cholesterol levels in mildly hypercholesterolemic men.

The effects of oat bran and wheat bran on plasma lipid concentrations were compared in a crossover study. Each bran (123 g oat bran or 54 g wheat bran) added nearly 18 g of nonstarch polysaccharide to a background diet containing about 10 g nonstarch polysaccharide. Twenty-three men (average plasma cholesterol level = 5.84 mmol/L, and low-density-lipoprotein (LDL) cholesterol level = 4.11 mmol/L) were randomly assigned to either the oat or wheat bran diet for 4 weeks and then changed to the alternate bran diet for a similar period. The oat bran diet produced significantly lower levels of plasma total cholesterol and LDL cholesterol: 5.65 +/- 0.16 and 3.88 +/- 0.15 mmol/L (mean +/- standard error) for oat bran vs 5.89 +/- 0.16 and 4.11 +/- 0.16 mmol/L for wheat bran. Food intake diaries showed that average consumption of total fat and saturated fat was identical during the two test periods, which excluded displacement of fat as an explanation for lowering of plasma cholesterol by oat bran. Our results indicate that in mildly hypercholesterolemic men, a diet high in soluble oat fiber can significantly lower plasma total cholesterol and LDL cholesterol and thus potentially lower the risk of coronary heart disease.     

Effects of a new soy/beta-sitosterol supplement on plasma lipids in moderately hypercholesterolemic subjects

Our aim was to test the hypocholesterolemic effect of a low-dose formulation of soy proteins supplemented with isolated b-sitosterol in a ratio of 4:1 in 20 moderately hypercholesterolemic subjects. The study has been divided in three different periods of forty days each: a stabilization diet period, then a treatment period during which all subjects assumed 10 g one time a day of the tested product and, finally, a wash out period. From the end of the stabilization diet period to the end of the soy protein added in b-sitosterol supplementation we observed a 0.45±0.30 mmol/L, 0.09±0.31 mmol/L and 0.17±0.22 mmol/L mean±SE decrease in respectively LDL-C, TG and apoB levels, associated with a 0.12±0.25 and 0.03±0.51 mg/dL mean increase respectively in HDL-C and apoA plasma concentrations. According to this recommends, low doses of soy protein added in b-sitosterol seems to be a practical and safe alternative for patients seeking modest reductions in LDL-C (<15%). J Am Diet Assoc. 2002;102:1807-1811.     

Neither glutamine nor arginine supplementation of diets increase glutamine body stores in healthy growing rats

The aim of the work was to resolve whether glutamine and arginine supplemented diets affect plasma and tissue (muscle, liver and intestinal mucosa) glutamine concentrations, as well as glutaminase and glutamine synthetase specific activities. The trial was performed in growing rats fed 10% protein diets for 3 weeks. Protein sources were: whey proteins (W); whey proteins+free glutamine (WG); whey proteins+arginine (WA); and casein+wheat protein hydrolysate+acid whey (39:39:22), as source containing protein-bound glutamine (CGW). Rats fed the control diet (6.4% glutamine) (W) showed comparable glutamine body stores to those of rats fed the WG diet. In fact, glutamine sup- plementation down-regulated the hepatic glutamine synthetic capacity of growing rats (W/WG: 6.8+/-0.3 vs 6.0+/-0.2 nmol/min/mg protein). Arginine supplementation of the diet (up to 9% of the protein content) resulted in a decrease in plasma and tissue glutamine concentrations (W/WA: plasma, 1218+/-51 vs 1031+/-48 micromol/L; liver 7.5+/-0.4 vs 6.5+/-0.2 micromol/g; muscle: 5.7+/-0.2 vs 4.0+/-0.2 micromol/g). These data suggest that glutamine supplementation of the diet does not increase plasma and tissue glutamine concentrations in healthy growing rats, while the addition of arginine to the diet decreases glutamine body stores.     

大豆蛋白和高钙摄入对高血胆固醇模型大鼠血脂水平的影响

目的探讨膳食大豆蛋白和/或高钙摄入对高血胆固醇模型大鼠血浆胆固醇及有关血脂指标的影响.方法用含5%猪油、1%胆固醇和0.25%胆碱的高脂饲料喂饲健康Wistar雌性大鼠,经14d诱发高血胆固醇以后,测血浆总胆固醇(TC),总甘油三酯(TG),高密度脂蛋白胆固醇(HDL-C)和载脂蛋白B(ApoB100)的浓度.然后,按体重和血浆胆固醇浓度将动物均衡分为4组,以2×2析因设计,分别喂饲含有酪蛋白和大豆分离蛋白及正常钙(0.59%)和高钙水平(1.12%)的纯合成高脂饲料.经21d喂养后,采血,测定指标同前.实验结果用SPSS统计软件进行方差分析.结果经14d诱导高血脂后,实验模型大鼠的TC水平为(4.10±1.11)mmol/L(n=24),而喂饲正常饲料的阴性对照鼠仅为(1.92±0.28)mmol/L(n=8),升高了2.14倍.又经21d喂饲含有处理因素的饲料后,酪蛋白组,酪蛋白加钙组,大豆蛋白组和大豆蛋白加钙组大鼠的TC水平分别为(10.56±2.74,7.99±2.19,5.48±0.51和6.81±0.98)mmol/L;ApoB100为(0.46±0.14,0.31±0.12,0.17±0.07和0.21±0.05)g/L.同酪蛋白组相比,其他3组动物的TC和ApoB100浓度显著降低.而各组间TG和HDL-C的变化均无显著性.结论膳食大豆蛋白和/或高钙摄入均可降低高血胆固醇模型大鼠的TC和ApoB100浓度,但对TG和HDL-C的作用不明显.大豆蛋白是这种作用的主要因素,但同时存在大豆蛋白和高钙摄入的相互作用.膳食大豆蛋白和高钙摄入的降血胆固醇机制还需要进一步探讨和研究.     

Hypocholesterolemic effect of an enteric-coated garlic supplement.

OBJECTIVE: To evaluate the hypocholesterolemic effect of an enteric-coated garlic supplement standardized for allicin-releasing potential in mild to moderate hypercholesterolemic patients. METHODS: A double-blind randomized, placebo-controlled intervention study was conducted in 46 hypercholesterolemic subjects who had failed or were not compliant with drug therapy. Each subject was given dietary counseling to lower fat intake and enteric-coated Australian garlic powder tablets with 9.6 mg allicin-releasing potential or matching placebo tablets. RESULTS: After 12 weeks, the garlic supplement group (n=22) had a significant reduction in total cholesterol (TC, -0.36 mmol/L. -4.2%) and LDL-cholesterol (LDL-C, -0.44 mmol/L, -6.6%) while the placebo group (n=24) had a non-significant increase in TC (0.13 mmol/L, 2.0%) and LDL-C (0.18 mmol/L, 3.7%). HDL-cholesterol was significantly increased in the placebo group (0.09 mmol/L, 9.1%), compared to the garlic group (-0.02 mmol/L, -0.9%). and no significant difference in triglycerides or in LDL/HDL ratio was observed between groups. CONCLUSIONS: The study demonstrates that enteric-coated garlic powder supplements with 9.6 mg allicin-releasing potential may have value in mild to moderate hypercholesterolemic patients when combined with a low fat diet. Taken with other evidence, the efficacy of garlic for lipoprotein metabolism might require allicin bioavailability to be enhanced through the use of, for example, an enteric-coated dose form. If this is the case, the possibility remains that greater hypocholesterolemic efficacy may be evident at a higher allicin dose. Also noteworthy in this study was a small reduction in energy intake with garlic compared with placebo, attributable to reduction in fat, carbohydrate and alcohol intakes. This may also have contributed to the effects on blood lipids. This study suggests that garlic supplementation has a cholesterol-lowering effect, which may be mediated by direct action of a biologically active compound or compounds and in part through the effect on food and nutrient intake.     

A mixed Australian fish diet and fish-oil supplementation: impact on the plasma lipid profile of healthy men

Twelve healthy men were fed in turn three diets for 6 wk each in a 3 x 3 randomized block design: a control diet (essentially fish free), a fish diet (200 g lean Australian fish flesh/d), and the same fish-based meal but supplemented with 5 g fish oil/d. Dietary eicosapentaenoic acid [EPA, 20: 5n-3 (omega-3)] was strongly associated with erythrocyte membrane EPA (r = 0.908 at 6 wk), strengthening its value as a measure of compliance in fish and fish-oil feeding trials. On the fish diet, subjects had increased incorporation of n-3 polyunsaturated fatty acids (PUFAs) at the expense of n-6 PUFAs in their erythrocyte membranes. When the fish-based diet was supplemented with fish oil (5 g/d), there was a significant lowering of plasma triacylglycerol (-0.16 +/- 0.24 mmol/L; mean +/- SD). No change in plasma total cholesterol was detected although the fish + oil diet produced a reduction in very-low-density-lipoprotein cholesterol (-0.24 +/- 0.26 mmol/L).