Sesame supplementation does not improve cardiovascular disease risk markers in overweight men and women.

BACKGROUND AND AIMS: Pre-clinical studies suggest that sesame and its lignans induce beneficial changes in risk factors related to cardiovascular disease and increase the bioavailability of mammalian lignans. However, only very few intervention trials have investigated the potential bioactivities of sesame in humans. We aimed to investigate the effects of sesame supplementation in humans on blood lipids, blood pressure, systemic oxidative stress, inflammatory biomarkers and mammalian lignan metabolism. METHODS AND RESULTS: We conducted a randomized, placebo-controlled cross-over intervention trial at a university research centre. Overweight or obese men and women (n=33) consumed 25g/d of sesame ( approximately 50mg/d of sesame lignan) and an iso-caloric placebo matched for macronutrient composition for 5 wks each. Each intervention period was preceded by a 4-wk washout period. Blood lipid profiles, day time ambulatory blood pressure, oxidative stress and inflammatory biomarkers and urinary mammalian lignans were measured before and after each intervention. Results are presented as the effect of sesame supplementation relative to placebo. Urinary excretion of the mammalian lignans, enterolactone and enterodiol, increased by approximately 8-fold (P<0.001). Blood lipids and blood pressure were not altered. In addition, markers of systemic inflammation (C-reactive protein, interleukin-6, tumor necrosis factor-alpha) and lipid peroxidation (F(2)-isoprostanes) were not affected. CONCLUSION: Supplementation with 25g/d of sesame can significantly increase the exposure to mammalian lignans. However, this did not cause any improvement in markers of cardiovascular disease risk in overweight or obese men and women.

Hospital admissions and length of stay for coronary disease in an Aboriginal cohort.

BACKGROUND AND AIMS: Coronary disease (CHD)-related hospital admission is more common among indigenous than non-indigenous Australians. We aimed to identify predictors of hospital admission potentially useful in planning prevention programs. METHODS AND RESULTS: Length of stay (LOS), interval between, and number of recurrent admissions were modelled with proportional hazards or negative binomial models using lifestyle data recorded in 1988-1989 among Aborigines (256 women, 258 men, aged 15-88years) linked to hospital records to 2002. Among 106 Aborigines with CHD, hypertension (hazard ratio (HR) 1.69, 95% CI 1.05-2.73); smoking (HR 1.90, 95% CI 1.02-3.53); consuming processed meat >4 times/month (HR 1.81, 95% CI 1.01-3.24); >6 eggs/week (HR 1.73, 95% CI 1.03-2.94); and lower intake of alcohol (HR 0.54, 95% CI 0.35-0.83) predicted LOS. Eating eggs (HR 1.05, 95% CI 1.01-1.09) and bush meats > or =7 times/month (HR 0.46, 95% CI 0.23-0.92) predicted interval between recurrent admissions. Hypertension (IRR 4.07; 95% CI 1.32-12.52), being an ex-drinker (IRR 6.60, 95% CI 2.30-19.00), eating red meat >6 times/week (IRR 0.98, 95% CI 0.97-0.99), bush meats >7 times/month (IRR 0.26, 95% CI 0.10-0.67), and adding salt to meals (IRR 3.16, 95% CI 1.12-8.92) predicted number of admissions. CONCLUSION: Hypertension, alcohol drinking, smoking, and diet influence hospital admissions for CHD in Aboriginal Australians.

The frequency of high-grade intraepithelial neoplasia in anal/perianal warts is higher than previously recognized.

A retrospective review of the prevalence of intraepithelial neoplasia (IN) in surgically removed perianal/anal warts from December 1995 to December 2004 was undertaken in patients referred to the Sexual Health Clinic at Royal Perth Hospital. Data were analysed from 115 men and 38 women, 29 of whom had HIV infection (27 men and two women). Perianal/anal IN within the warts was found in 78% (52% high grade) of men with HIV infection. In men without HIV infection, the overall rate of IN within warts was 33% (20% high grade). The IN rate was 8.3% for HIV-negative women (2.8% high grade). Rates of IN within perianal/anal warts in men with or without HIV infection are higher than previously reported, and suggest the likelihood of a substantial increase in the future incidence of anal cancer. The association between IN and genital warts needs to be further studied.

Differential effects of eicosapentaenoic acid and docosahexaenoic acid on vascular reactivity of the forearm microcirculation in hyperlipidemic, overweight men.

BACKGROUND: Recent evidence supports differential effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), the 2 major omega3 fatty acids of marine origin, on blood pressure in humans and vascular reactivity in adult spontaneously hypertensive rats. We investigated possible differences in the effects of purified EPA or DHA on forearm vascular reactivity in overweight hyperlipidemic men that might contribute to the blood pressure-lowering effects of fish oils. METHODS AND RESULTS: With a double-blind, placebo-controlled trial of parallel design, 59 overweight, mildly hyperlipidemic men were randomized to receive 4 g/d purified EPA, DHA, or olive oil (placebo) capsules while continuing their usual diets for 6 weeks. Forearm blood flow (FBF) was measured with venous occlusion, strain-gauge plethysmography during the sequential intra-arterial administration of acetylcholine (7.5, 15, and 30 microg/min), sodium nitroprusside (1.5, 3, and 10 microg/min), norepinephrine (10, 20, and 40 ng/min), a single-dose infusion of N:(G)-monomethyl-L-arginine (L-NMMA) (1 mg/min), and coinfusion of acetylcholine (7.5, 15, and 30 microg/min) and L-NMMA. Forty of the 56 subjects who completed the study underwent FBF measurements. Plasma phospholipid EPA levels increased significantly (P:<0.0001) after supplementation with EPA, and DHA composition increased with DHA supplementation (P:<0.0001). Relative to placebo, DHA, but not EPA, supplementation significantly improved FBF in response to acetylcholine infusion (P:=0.040) and coinfusion of acetylcholine with L-NMMA (P:=0.040). Infusion of L-NMMA alone showed no group differences. DHA significantly enhanced dilatory responses to sodium nitroprusside (P:<0.0001) and attenuated constrictor responses to norepinephrine (P:=0.017). CONCLUSIONS: Relative to placebo, DHA, but not EPA, enhances vasodilator mechanisms and attenuates constrictor responses in the forearm microcirculation. Improvements in endothelium-independent mechanisms appear to be predominant and may contribute to the selective blood pressure-lowering effect observed with DHA compared with EPA in humans.

Effect of streptozotocin on red-blood-cell-reduced glutathione: modification by glucose, nicotinamide, and epinephrine.

Previous studies had shown that administration of streptozotocin to rats produces both diabetes and hemolysis and that both could be ameliorated by prior injections of diazoxide. Thus, it appeared pertinent to define the effect of streptozotocin on the red cell. In the present studies, streptozotocin administered in vivo to rats produced a rapid fall in red-cell-reduced glutathione. This effect was duplicated in vitro in incubated human red cells. Furthermore, it was demonstrated that glucose loading prior to bleeding modified the in-vitro red-cell GSH response to streptozotocin and that preincubation of red cells from fasted individuals with glucose, nicotinamide, and epinephrine (but not nicotinic acid) protected against the subsequent effect of streptozotocin on RBC GSH. The pattern of the RBC GSH response under each of these conditions is that which occurs in response to challenge with an oxidant, that is, with appropriate protection, oxidation stress produces an acute rise rather than falll in gsh. further, when glucose was present through both preincubation and test periods (i.e., in presence of streptozotocin) a third pattern of GSH response was observed--no change. The data are compatible with the postulate that the cytotoxic action of streptozotocin is dependent, in part, on an oxidant effect, and that glucose may protect through at least two mechanisms, that adrenergic stimulation can enhance protective mechanisms against redox insults and so contribute to maintenance of cell viability.

Differential effect of aspirin on platelet aggregation in IDDM.

Diabetes mellitus is associated with a high incidence of cardiovascular diseases not directly attributable to hyperlipidemia, smoking, or hypertension, but which in part may be explained by an enhanced tendency to thrombosis due to increased platelet activity. The aim of this study was to evaluate platelet function and compare the effectiveness of the antiplatelet drug aspirin on platelet aggregation in diabetic and nondiabetic subjects. Platelet aggregation and composition were examined in 20 male insulin-dependent diabetes mellitus (IDDM) patients and 20 nondiabetic control subjects matched for age and body mass index. All were normotensive with serum total cholesterol less than 6.5 mM. Although within the clinically acceptable normal range, blood pressure was significantly higher in diabetic patients (130/75 mmHg) than in control subjects (123/70 mmHg) (P less than 0.05). Serum thromboxane B2 and ex vivo aggregation of platelets in response to two doses of the agonists collagen and platelet-activating factor (PAF) were similar to nondiabetic subjects. However, after taking 100 mg/day aspirin for 5 days, platelet aggregation to collagen was reduced by 76% in control subjects compared to 56% in IDDM patients (P less than 0.001). Aspirin treatment also reduced the slope of the aggregation curve and increased the lag time (the period between the addition of collagen and the start of irreversible aggregation) significantly more in control than in diabetic platelets. This difference in platelet aggregation could not be attributed to differences in platelet serotonin or thromboxane A2 secretion, the latter being almost completely suppressed by aspirin in each group. Platelet aggregation to PAF was similar in both groups and was not affected by aspirin.(ABSTRACT TRUNCATED AT 250 WORDS)

The independent and combined effects of aerobic exercise and dietary fish intake on serum lipids and glycemic control in NIDDM. A randomized controlled study.

OBJECTIVE: The triglyceride-lowering effects of omega-3 fats and HDL cholesterol-raising effects of exercise may be appropriate management for dyslipidemia in NIDDM. However, fish oil may impair glycemic control in NIDDM. The present study examined the effects of moderate aerobic exercise and the incorporation of fish into a low-fat (30% total energy) diet on serum lipids and glycemic control in dyslipidemic NIDDM patients. RESEARCH DESIGN AND METHODS: In a controlled, 8-week intervention, 55 sedentary NIDDM subjects with serum triglycerides > 1.8 mmol/l and/or HDL cholesterol < 1.0 mmol/l were randomly assigned to a low-fat diet (30% daily energy intake) with or without one fish meal daily (3.6 g omega-3/day) and further randomized to a moderate (55-65% VO2max) or light (heart rate < 100 bpm) exercise program. An oral glucose tolerance test (75 g), fasting serum glucose, insulin, lipids, and GHb were measured before and after intervention. Self-monitoring of blood glucose was performed throughout. RESULTS: In the 49 subjects who completed the study, moderate exercise improved aerobic fitness (VO2max) by 12% (from 1.87 to 2.07 l/min, P = 0.0001). Fish consumption reduced triglycerides (0.80 mmol/l, P = 0.03) and HDL3 cholesterol (0.05 mmol/l, P = 0.02) and increased HDL2 cholesterol (0.06 mmol/l, P = 0.01). After adjustment for age, sex, and changes in body weight, fish diets were associated with increases in GHb (0.50%, P = 0.05) and self-monitored glucose (0.57 mmol/l, P = 0.0002), which were prevented by moderate exercise. CONCLUSIONS: A reduced fat diet incorporating one daily fish meal reduces serum triglycerides and increases HDL2 cholesterol in dyslipidemic NIDDM patients. Associated deterioration in glycemic control can be prevented by a concomitant program of moderate exercise.

Effects of coffee on ambulatory blood pressure in older men and women: A randomized controlled trial.

This study assessed the effects of regular coffee drinking on 24-hour ambulatory blood pressure (ABP) in normotensive and hypertensive older men and women. Twenty-two normotensive and 26 hypertensive, nonsmoking men and women, with a mean age of 72.1 years (range, 54 to 89 years), took part in the study. After 2 weeks of a caffeine-free diet, subjects were randomized to continue with the caffeine-free diet and abstain from caffeine-containing drinks or drink instant coffee (5 cups per day, equivalent to 300 mg caffeine per day) in addition to the caffeine-free diet for a further 2 weeks. Change in systolic and diastolic blood pressures (SBP, DBP) determined by 24-hour ambulatory BP monitoring showed significant interactions between coffee drinking and hypertension status. In the hypertensive group, rise in mean 24-hour SBP was greater by 4.8 (SEM, 1.3) mm Hg (P=0.031) and increase in mean 24-hour DBP was higher by 3.0 (1.0) mm Hg (P=0.010) in coffee drinkers than in abstainers. There were no significant differences between abstainers and coffee drinkers in the normotensive group for 24-hour, daytime, or nighttime SBP or DBP. In older men and women with treated or untreated hypertension, ABP increased in coffee drinkers and decreased in abstainers. Restriction of coffee intake may be beneficial in older hypertensive individuals.

Docosahexaenoic acid but not eicosapentaenoic acid lowers ambulatory blood pressure and heart rate in humans.

Animal studies suggest that the 2 major omega3 fatty acids found in fish, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), may have differential effects on blood pressure (BP) and heart rate (HR). The aim of this study was to determine whether there were significant differences in the effects of purified EPA or DHA on ambulatory BP and HR in humans. In a double-blind, placebo-controlled trial of parallel design, 59 overweight, mildly hyperlipidemic men were randomized to 4 g/d of purified EPA, DHA, or olive oil (placebo) capsules and continued their usual diets for 6 weeks. Fifty-six subjects completed the study. Only DHA reduced 24-hour and daytime (awake) ambulatory BP (P<0.05). Relative to the placebo group, 24-hour BP fell 5.8/3.3 (systolic/diastolic) mm Hg and daytime BP fell 3.5/2.0 mm Hg with DHA. DHA also significantly reduced 24-hour, daytime, and nighttime (asleep) ambulatory HRs (P=0. 001). Relative to the placebo group, DHA reduced 24-hour HR by 3. 5+/-0.8 bpm, daytime HR by 3.7+/-1.2 bpm, and nighttime HR by 2. 8+/-1.2. EPA had no significant effect on ambulatory BP or HR. Supplementation with EPA increased plasma phospholipid EPA from 1. 66+/-0.07% to 9.83+/-0.06% (P<0.0001) but did not change DHA levels. Purified DHA capsules increased plasma phospholipid DHA levels from 4.00+/-0.27% to 10.93+/-0.62% (P<0.0001) and led to a small, nonsignificant increase in EPA (1.52+/-0.12% to 2.26+/-0.16%). Purified DHA but not EPA reduced ambulatory BP and HR in mildly hyperlipidemic men. The results of this study suggest that DHA is the principal omega3 fatty acid in fish and fish oils that is responsible for their BP- and HR-lowering effects in humans. These results have important implications for human nutrition and the food industry.

Effects on blood pressure of omega 3 fats in subjects at increased risk of cardiovascular disease.

This study was conducted to compare the effects of omega 3 fatty acids, taken as fish or fish-oil supplements in the setting of a high- or low-fat dietary background, on blood pressure and heart rate in men with moderate cardiovascular risks. One hundred twenty men were randomly allocated to five high-fat (40% of daily energy) and two low-fat (30% of energy) groups to undertaken a 12-week dietary intervention period involving fish, fish oil, or a combination of these. Sodium intake was restricted to less than 90 mmol/d. The five high-fat groups were assigned to take either 6 or 12 fish-oil capsules daily, fish or a combination of fish oil and fish, or placebo capsules. The two low-fat groups took either fish or placebo capsules. Fish meals were devised to provide 1.3 g of eicosapentaenoic acid daily, equivalent to that contained in 6 fish-oil capsules. Subjects were instructed to eat a selection of fish that provided an average of 3.65 g/d (range, 3.2 to 4.1 g/d) of total omega 3 fatty acids. Subjects were seen at regular intervals during the baseline and dietary intervention periods for measurement of weight, blood pressure, heart rate, dietary compliance, urinary electrolyte excretion, platelet phospholipid fatty acids, blood glucose, and insulin concentration. There was a greater fall in both systolic and diastolic blood pressures in subjects allocated fish or fish oil, particularly in the low-fat groups, compared with control subjects. However, there was no significant group effect.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of dietary fish and weight reduction on ambulatory blood pressure in overweight hypertensives.

Obesity is a major factor contributing to hypertension and increased risk of cardiovascular disease. Regular consumption of dietary fish and omega3 fatty acids of marine origin can lower blood pressure (BP) levels and reduce cardiovascular risk. This study examined the potential effects of combining dietary fish rich in omega3 fatty acids with a weight loss regimen in overweight hypertensive subjects, with ambulatory BP levels as the primary end point. Using a factorial design, 69 overweight medication-treated hypertensives were randomized to a daily fish meal (3.65 g omega3 fatty acids), weight reduction, the 2 regimens combined, or a control regimen for 16 weeks. Sixty-three subjects with a mean+/-SEM body mass index of 31.6+/-0.5 kg/m2 completed the study. Weight fell by 5.6+/-0.8 kg with energy restriction. Dietary fish and weight loss had significant independent and additive effects on 24-hour ambulatory BP. Effects were greatest on awake systolic and diastolic BP (P<0.01); relative to control, awake pressures fell 6.0/3.0 mm Hg with dietary fish alone, 5.5/2.2 mm Hg with weight reduction alone, and 13.0/9.3 mm Hg with fish and weight loss combined. These results also remained significant after further adjustment for changes in urinary sodium, potassium, or the sodium/potassium ratio, as well as dietary macronutrients. Dietary fish also significantly reduced 24-hour (-3.1+/-1.4 bpm, P=0.036) and awake (-4.2+/-1.6 bpm, P=0. 013) ambulatory heart rates. Weight reduction had a significant effect on sleeping heart rate only (-3.2+/-1.7 bpm, P=0.037). Combining a daily fish meal with a weight-reducing regimen led to additive effects on ambulatory BP and decreased heart rate. The effects were large, suggesting that cardiovascular risk and antihypertensive drug requirements are likely to be reduced substantially by combining dietary fish meals rich in omega3 fatty acids with weight-loss regimens in overweight medication-treated hypertensives. The reduction in heart rate seen with dietary fish suggests a cardiac/autonomic component, as well as vascular effects, of increased consumption of omega3 fatty acid from fish.

Red wine polyphenols, in the absence of alcohol, reduce lipid peroxidative stress in smoking subjects.

Phenolic compounds in red wine can exert antioxidant effects on in vitro lipoprotein oxidation. This has led to speculation that red wine consumption mediates unique anti-atherosclerotic effects compared to other alcoholic beverages. However, studies assessing the effects of red wine consumption on lipoprotein oxidation ex vivo have not been conclusive. The recent identification of the F2-isoprostanes as oxidative products of arachidonic acid has provided a reliable measure of in vivo lipid peroxidation. This randomized trial investigated changes in plasma and urinary F2-isoprostane concentrations following red wine, white wine, or dealcoholized red wine consumption in humans. Eighteen male smokers consumed, in random order, red wine, white wine, or dealcoholized red wine, for two weeks with one week washout between beverages. Plasma and urinary F2-isoprostane concentrations were measured before and after each beverage. Serum gamma-glutamyl transpeptidase (gamma-GT) and urinary 4-O -methylgallic acid were measured as markers of alcohol consumption and phenolic acid absorption, respectively. Plasma F2-isoprostanes (p < .05) decreased significantly with dealcoholized red wine but not with the alcohol-containing beverages. Urinary excretion of F2-isoprostanes showed a similar trend. gamma-GT decreased significantly with dealcoholized red wine and increased with both alcohol-containing beverages (p < .01). Urinary excretion of 4-O-methylgallic acid increased significantly (p < .001) in the 24 h urine samples following red wine or dealcoholized red wine ingestion, but not with white wine. Serum urate increased and beta-carotene decreased with both alcoholic beverages relative to dealcoholized red wine. There was no change in the antioxidants alpha- and gamma-tocopherol or vitamin C with any of the beverages. The results suggest that polyphenols in dealcoholized red wine can reduce in vivo lipid peroxidation as measured by F2-isoprostanes in smoking subjects. However, no reduction in lipid peroxidation was observed following red or white wine consumption, suggesting that any protective effects of wine drinking on cardiovascular disease are unlikely to be related to inhibition of lipid oxidation.

Impaired gastric function in experimental malnutrition.

Selective dietary protein deprivation led to impaired pentagastrin stimulated gastric acid secretion in rats but was not simply due to lower body weights in the experimental group. This may be a significant pathophysiological factor in clinical malnutrition because of reduction of gastric acid control over bacterial populations in upper intestinal secretions.

Dietary fatty acids and progression of coronary artery disease in men.

We examined associations between dietary fatty acids and progression of coronary artery disease (CAD) in 50 men receiving a lipid-lowering diet or usual care in the St Thomas' Atherosclerosis Regression Study. Nutrient intake was assessed by dietary history and computerized food tables. Progression of CAD over 39 mo, measured by a decrease in minimum absolute width of coronary segments (MinAWS) on angiography, was highly correlated with intakes of palmitic, stearic (18:0), palmitoleic, and elaidic (t-18:1) acids (P < 0.001); no protective effects were found with polyunsaturates. Total saturates and trans unsaturates explained 20% of variance in CAD progression. After adjustment for plasma cholesterol and other risk factors, change in MinAWS was most closely associated with intakes of 18:0 and t-18:1 fatty acids (P = 0.009). We suggest that progression of CAD in men is strongly related to intakes of both long-chain saturates and trans unsaturates, the effects of 18:0 and t-18:1 possibly being independent of plasma cholesterol concentration.

Effect of microorganisms isolated from the upper gut of malnourished children on intestinal sugar absorption in vivo.

The effect of microorganisms isolated from the upper gastrointestinal tract of malnourished children on intestinal sugar absorption was studied in rats in vivo. Pure cultures of organisms were grown overnight in a nutrient broth and the resultant supernatant fluid which contained microorganisms in similar numbers to those found in the patients was used as the basic solution for jejunal perfusions which were done in anesthetized adult Wistar rats. The substrate used was arbutin (p-hydroxphenyl-beta-glucoside), a recognized marker of intestinal active sugar transport. Of the gram-positive cocci studied, only the saprophyte, Staphylococcus saprophyticus, did not adversely affect the intestinal absorption of arbutin. The only gram-positive rod studied, a lactobacillus, also significantly inhibited arbutin absorption. Of the Enterobacteriaciae studied, Salmonella paratyphi B, a Shigella and Proteus sp. did not affect arbutin absorption. All the species of Escherichia coli studied, including a nonpathogenic variety, inhibited absorption. Klebsiella sp. and Pseudomonas sp. were also effective. Of the Candida sp., C. albicans and C. parapsilosis were inhibitory while C. tropicalis was not. These results suggest that microorganisms not generally considered enteropathogenic may adversely affect intestinal function when present in the lumen of the gut in excessive numbers and contribute to the production of diarrhea in children with malnutrition.

Effects of varying dietary fat, fish, and fish oils on blood lipids in a randomized controlled trial in men at risk of heart disease.

This study aimed to determine the effects of incorporating fish with 40%- or 30%-fat diets and the differences in response to fish or fish oil omega 3 fats. Men with high-normal blood pressure and elevated serum cholesterol were randomly allocated to one of seven diets for 12 wk. Fish or fish oil with a 40%-fat diet increased total cholesterol, HDL cholesterol, HDL2 cholesterol, and LDL cholesterol, and reduced triglycerides. The 30%-fat diet alone reduced cholesterol, LDL cholesterol, and HDL cholesterol, with triglycerides unchanged. Fish with the 30%-fat diet reduced cholesterol, LDL cholesterol, and triglycerides and increased HDL2 cholesterol. This study has shown that plasma lipids are affected similarly by fish or fish oil in men consuming a 40%-fat diet. Adverse effects of omega 3 fats on total and LDL cholesterol are reversed by a 30%-fat diet, whereas one daily fish meal substantially lowers triglycerides and reverses the fall in HDL cholesterol that is usual with a low-fat diet.

Acute effects of ingestion of black and green tea on lipoprotein oxidation.

BACKGROUND: Tea has been associated with a reduced risk of cardiovascular disease. One proposed mechanism of this risk reduction involves inhibition of lipoprotein oxidation in vivo by antioxidant polyphenolic compounds derived from tea. However, controlled interventions uniformly failed to show that ingestion of tea can inhibit LDL oxidation ex vivo. The absence of effects in previous studies may be due to the isolation of LDL particles from polyphenolic compounds that are present in the aqueous phase of serum. OBJECTIVE: The objective of this study was to examine the acute effects of ingestion of black and green tea on ex vivo Cu(2+)-induced lipoprotein oxidation without prior isolation of lipoproteins from serum. DESIGN: The acute effects of 4 hot drinks-green tea and black tea (each at a dose equivalent to 4 standard cups), water matched to the teas for caffeine content, and water-were assessed in 20 healthy men by using a Latin-square design. The lag time to lipoprotein diene formation, slope of the propagation phase of the oxidation curve, and area under the oxidation curve were calculated. Urinary concentrations of 4-O-methylgallic acid were used as a marker of uptake and metabolism of polyphenolic compounds from tea. RESULTS: Significant increases in urinary 4-O-methylgallic acid for black and green tea (P < 0. 0001) were observed. Caffeine did not significantly influence lipoprotein oxidation. Compared with the water control, there was a greater lag time for black tea (5.4 +/- 2.9 min; P = 0.05) that was of borderline significance and a similar trend for green tea (4.4 +/- 2.8 min; P = 0.17). Slope and area under the oxidation curve were not altered. CONCLUSION: Black tea has a mild acute effect on ex vivo lipoprotein oxidation in human serum. 2000;71:-7.

Purified eicosapentaenoic and docosahexaenoic acids have differential effects on serum lipids and lipoproteins, LDL particle size, glucose, and insulin in mildly hyperlipidemic men.

BACKGROUND: Regular consumption of n-3 fatty acids of marine origin can improve serum lipids and reduce cardiovascular risk. OBJECTIVE: This study aimed to determine whether eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids have differential effects on serum lipids and lipoproteins, glucose, and insulin in humans. DESIGN: In a double-blind, placebo-controlled trial of parallel design, 59 overweight, nonsmoking, mildly hyperlipidemic men were randomly assigned to receive 4 g purified EPA, DHA, or olive oil (placebo) daily while continuing their usual diets for 6 wk. RESULTS: Fifty-six men aged 48.8 +/- 1.1 y completed the study. Relative to those in the olive oil group, triacylglycerols fell by 0.45 +/- 0.15 mmol/L ( approximately 20%; P = 0.003) in the DHA group and by 0.37 +/- 0.14 mmol/L ( approximately 18%; P = 0.012) in the EPA group. Neither EPA nor DHA had any effect on total cholesterol. LDL, HDL, and HDL(2) cholesterol were not affected significantly by EPA, but HDL(3) cholesterol decreased significantly (6.7%; P = 0.032). Although HDL cholesterol was not significantly increased by DHA (3. 1%), HDL(2) cholesterol increased by approximately 29% (P = 0.004). DHA increased LDL cholesterol by 8% (P = 0.019). Adjusted LDL particle size increased by 0.25 +/- 0.08 nm (P = 0.002) with DHA but not with EPA. EPA supplementation increased plasma and platelet phospholipid EPA but reduced DHA. DHA supplementation increased DHA and EPA in plasma and platelet phospholipids. Both EPA and DHA increased fasting insulin significantly. EPA, but not DHA, tended to increase fasting glucose, but not significantly so. CONCLUSIONS: EPA and DHA had differential effects on lipids, fatty acids, and glucose metabolism in overweight men with mild hyperlipidemia.

Dietary fish as a major component of a weight-loss diet: effect on serum lipids, glucose, and insulin metabolism in overweight hypertensive subjects.

BACKGROUND: Obesity in hypertensive patients is associated with dyslipidemia and insulin resistance, both of which are improved by weight control. n-3 Fatty acids have diverse effects on mechanisms underlying atherosclerosis, including a decrease in serum triacylglycerols and an increase in HDL(2) cholesterol. OBJECTIVE: The objective was to examine whether dietary fish enhances the effects of weight loss on serum lipids, glucose, and insulin in 69 overweight, treated hypertensive patients. DESIGN: Overweight patients being treated for hypertension were randomly assigned to either a daily fish meal (3.65 g n-3 fatty acids), a weight-loss regimen, the 2 regimens combined, or a control group for 16 wk. RESULTS: Sixty-three subjects completed the study. Weight decreased by a mean (+/-SEM) of 5.6 +/- 0.8 kg with energy restriction. Weight loss decreased fasting insulin (P = 0.003) and the area under the curve for insulin (P = 0.003) and glucose (P = 0.047) during an oral-glucose-tolerance test. The greatest decrease occurred in the fish + weight-loss group. There was no independent effect of fish on glucose or insulin. Fish increased HDL(2) cholesterol (P = 0.004) and decreased HDL(3) cholesterol (P = 0.026) without altering total, LDL, or HDL cholesterol. Weight loss had no effect on these variables. Fasting triacylglycerols fell significantly with fish consumption (29%) and weight loss (26%). The fish + weight-loss group showed the greatest improvement in lipids: triacylglycerols decreased by 38% (P < 0.001) and HDL(2) cholesterol increased by 24% (P = 0.04) compared with the control group. CONCLUSIONS: Incorporating a daily fish meal into a weight-loss regimen was more effective than either measure alone at improving glucose-insulin metabolism and dyslipidemia. Cardiovascular risk is likely to be substantially reduced in overweight hypertensive patients with a weight-loss program incorporating fish meals rich in n-3 fatty acids.

Lipoprotein lipase D9N, N291S and S447X polymorphisms: their influence on premature coronary heart disease and plasma lipids.

Lipoprotein lipase (LPL) plays a pivotal role in lipoprotein metabolism. Three recently described exonic polymorphisms of the gene, D9N, N291S and S447X, have been variably found to influence plasma lipids while effects on coronary heart disease (CHD) are less well documented. Two predominantly Caucasian groups were studied: CHD patients <50 years of age, with angiographically documented CHD; and a randomly recruited community control group without a history of heart disease. The 9N allele of the D9N polymorphism was present in 25 of 428 (5.8%) of Caucasian males with CHD and in seven of 291 (2.4%) of corresponding community subjects (odds ratio, 2.5; 95% confidence interval (CI), 1.1-5.9; P=0.03) and was also significantly over-represented in the Caucasian males with myocardial infarction (MI) (21 of 308 or 6.8%; odds ratio, 2.6; 95% CI, 1.1-5.9; P=0.01). The distributions of the other two polymorphisms were similar in the CHD and community groups. In multivariate models adjusted for age, sex, diabetes, body mass index, smoking, lipid levels and race, the D9N polymorphism remained significantly related to both CHD and MI, with an odds ratio >2. There were, generally, trends to more adverse fasting plasma high-density lipoprotein (HDL) cholesterol and triglycerides in carriers of the 291S and 9N alleles, and the opposite trends for triglycerides in 447X carriers. In the community group, male carriers of 291S (n=13) had significantly (20%) lower HDL cholesterol than corresponding non-carriers (n=323), 0.98+/-0.07 mmol/l (mean+/-S.E.) versus 1.22+/-0.02 mmol/l (P<0.005), while HDL cholesterol was not different in male carriers (n=8) and non-carriers (n=296) of 9N (1.23+/-0.13 mmol/l versus 1.22+/-0.02 mmol/l). Multivariate analysis confirmed that the 291S allele carrier status conferred a significantly lower HDL cholesterol (P=0.001) and the 447X allele lower triglyceride (P<0.01) in the community group. In conclusion, LPL 9N carrier status was unequivocally related to premature CHD and to MI in males, strongly supporting recent results in older aged males. The somewhat different effects of the D9N and N291S polymorphisms on plasma lipids, and the absence of a clear effect of the N291S on CHD, raise the possibility that the effect of 9N carrier status might be mediated through effects on LPL function in addition to those influencing fasting plasma lipids.