ApoA-I/A-II-HDL positively associates with apoB-lipoproteins as a potential atherogenic indicator.

BACKGROUND: We recently reported distinct nature of high-density lipoproteins (HDL) subgroup particles with apolipoprotein (apo) A-I but not apoA-II (LpAI) and HDL having both (LpAI:AII) based on the data from 314 Japanese. While plasma HDL level almost exclusively depends on concentration of LpAI having 3 to 4 apoA-I molecules, LpAI:AII appeared with almost constant concentration regardless of plasma HDL levels having stable structure with two apoA-I and one disulfide-dimeric apoA-II molecules (Sci. Rep. 6; 31,532, 2016). The aim of this study is further characterization of LpAI:AII with respect to its role in atherogenesis. METHODS: Association of LpAI, LpAI:AII and other HDL parameters with apoB-lipoprotein parameters was analyzed among the cohort data above. RESULTS: ApoA-I in LpAI negatively correlated with the apoB-lipoprotein parameters such as apoB, triglyceride, nonHDL-cholesterol, and nonHDL-cholesterol + triglyceride, which are apparently reflected in the relations of the total HDL parameters to apoB-lipoproteins. In contrast, apoA-I in LpAI:AII and apoA-II positively correlated to the apoB-lipoprotein parameters even within their small range of variation. These relationships are independent of sex, but may slightly be influenced by the activity-related CETP mutations. CONCLUSIONS: The study suggested that LpAI:AII is an atherogenic indicator rather than antiatherogenic. These sub-fractions of HDL are to be evaluated separately for estimating atherogenic risk of the patients.

Preventive effects of eicosapentaenoic acid on coronary artery disease in patients with peripheral artery disease.

BACKGROUND: The JELIS trial examined the preventive effects of eicosapentaenoic acid (EPA) on coronary artery disease (CAD) in hypercholesterolemia. Previous investigators have reported that patients with peripheral artery disease (PAD) have a poor prognosis due to the potential risk for CAD. We conducted a subanalysis to examine whether the incidence of CAD was high in patients with PAD and whether EPA prevented the occurrence of CAD. METHODS AND RESULTS: Of 18,645 the Japan EPA lipid intervention study (JELIS) patients, 223 had PAD (control group; complicated (n=77), newly diagnosed (n=29), EPA group; complicated (n=96), newly diagnosed (n=21)). We analyzed the incidence of major coronary events (MCE) in the 2 groups. Cox proportional hazard ratio adjusted for baseline risk factor levels was used to test differences between the 2 groups. The incidence of MCE in the control group was significantly higher in patients complicated with PAD and in those newly diagnosed with PAD than in patients without PAD (complicated: hazard ratio 1.97, P=0.039; newly diagnosed: hazard ratio 2.88, P=0.030). As for patients with PAD, the EPA group had a significantly lower MCE hazard ratio than the control group (hazard ratio 0.44, 95% confidence interval 0.19-0.97, P=0.041). CONCLUSIONS: Subanalysis of the JELIS trial demonstrated that in patients with PAD the incidence of CAD was higher than in controls, and that EPA markedly reduced the occurrence of CAD in those patients.

Reduction in the recurrence of stroke by eicosapentaenoic acid for hypercholesterolemic patients: subanalysis of the JELIS trial.

BACKGROUND AND PURPOSE: The JELIS trial examined the preventive effect of eicosapentaenoic acid (EPA) against coronary artery diseases. Hypercholesterolemic patients received statin only (no EPA group: n=9319) or statin with EPA (EPA group: n=9326) for around 5 years. EPA significantly suppressed the incidence of coronary events in previous analysis. Herein, we investigated the effects of EPA on the primary and secondary prevention of stroke. METHODS: We conducted a subanalysis of JELIS with respect to stroke incidence in the primary and secondary prevention subgroups defined as those without and with a prior history of stroke using Cox proportional hazard ratios, adjusted for baseline risk factor levels. RESULTS: As for primary prevention of stroke, this occurred in 114 (1.3%) of 8862 no EPA group and in 133 (1.5%) of 8841 EPA group. No statistically significant difference in total stroke incidence (Hazard Ratio, 1.08; 95% confidence interval, 0.95 to 1.22) was observed between the no EPA and the EPA groups. In the secondary prevention subgroup, stroke occurred in 48 (10.5%) of 457 no EPA group and in 33 (6.8%) of 485 EPA group, showing a 20% relative reduction in recurrent stroke in the EPA group (Hazard Ratio, 0.80; 95% confidence interval, 0.64 to 0.997). CONCLUSIONS: Administration of highly purified EPA appeared to reduce the risk of recurrent stroke in a Japanese population of hypercholesterolemic patients receiving low-dose statin therapy. Further research is needed to determine whether similar benefits are found in other populations with lower levels of fish intake. The trial is registered at ClinicalTrials.gov (number NCT00231738).

Effects of eicosapentaenoic acid on major coronary events in hypercholesterolaemic patients (JELIS): a randomised open-label, blinded endpoint analysis.

BACKGROUND: Epidemiological and clinical evidence suggests that an increased intake of long-chain n-3 fatty acids protects against mortality from coronary artery disease. We aimed to test the hypothesis that long-term use of eicosapentaenoic acid (EPA) is effective for prevention of major coronary events in hypercholesterolaemic patients in Japan who consume a large amount of fish. METHODS: 18 645 patients with a total cholesterol of 6.5 mmol/L or greater were recruited from local physicians throughout Japan between 1996 and 1999. Patients were randomly assigned to receive either 1800 mg of EPA daily with statin (EPA group; n=9326) or statin only (controls; n=9319) with a 5-year follow-up. The primary endpoint was any major coronary event, including sudden cardiac death, fatal and non-fatal myocardial infarction, and other non-fatal events including unstable angina pectoris, angioplasty, stenting, or coronary artery bypass grafting. Analysis was by intention-to-treat. The study was registered at ClinicalTrials.gov, number NCT00231738. FINDINGS: At mean follow-up of 4.6 years, we detected the primary endpoint in 262 (2.8%) patients in the EPA group and 324 (3.5%) in controls-a 19% relative reduction in major coronary events (p=0.011). Post-treatment LDL cholesterol concentrations decreased 25%, from 4.7 mmol/L in both groups. Serum LDL cholesterol was not a significant factor in a reduction of risk for major coronary events. Unstable angina and non-fatal coronary events were also significantly reduced in the EPA group. Sudden cardiac death and coronary death did not differ between groups. In patients with a history of coronary artery disease who were given EPA treatment, major coronary events were reduced by 19% (secondary prevention subgroup: 158 [8.7%] in the EPA group vs 197 [10.7%] in the control group; p=0.048). In patients with no history of coronary artery disease, EPA treatment reduced major coronary events by 18%, but this finding was not significant (104 [1.4%] in the EPA group vs 127 [1.7%] in the control group; p=0.132). INTERPRETATION: EPA is a promising treatment for prevention of major coronary events, and especially non-fatal coronary events, in Japanese hypercholesterolaemic patients.

Primary prevention of cardiovascular disease with pravastatin in Japan (MEGA Study): a prospective randomised controlled trial.

BACKGROUND: Evidence-based treatment for hypercholesterolaemia in Japan has been hindered by the lack of direct evidence in this population. Our aim was to assess whether evidence for treatment with statins derived from western populations can be extrapolated to the Japanese population. METHODS: In this prospective, randomised, open-labelled, blinded study, patients with hypercholesterolaemia (total cholesterol 5.69-6.98 mmol/L) and no history of coronary heart disease or stroke were randomly assigned diet or diet plus 10-20 mg pravastatin daily. The primary endpoint was the first occurrence of coronary heart disease. Statistical analyses were done by intention to treat. This trial is registered at ClinicalTrials.gov, number NCT00211705. FINDINGS: 3966 patients were randomly assigned to the diet group and 3866 to the diet plus pravastatin group. Mean follow-up was 5.3 years. At the end of study, 471 and 522 patients had withdrawn, died, or been lost to follow-up in the diet and diet plus pravastatin groups, respectively. Mean total cholesterol was reduced by 2.1% (from 6.27 mmol/L to 6.13 mmol/L) and 11.5% (from 6.27 mmol/L to 5.55 mmol/L) and mean LDL cholesterol by 3.2% (from 4.05 mmol/L to 3.90 mmol/L) and 18.0% (from 4.05 mmol/L to 3.31 mmol/L) in the diet and the diet plus pravastatin groups, respectively. Coronary heart disease was significantly lower in the diet plus pravastatin group than in the diet alone group (66 events vs 101 events; HR 0.67, 95% CI 0.49-0.91; p=0.01). There was no difference in the incidence of malignant neoplasms or other serious adverse events between the two groups. INTERPRETATION: Treatment with a low dose of pravastatin reduces the risk of coronary heart disease in Japan by much the same amount as higher doses have shown in Europe and the USA.

Risk of coronary events in Japanese patients with both hypercholesterolemia and type 2 diabetes mellitus on low-dose simvastatin therapy: implication from Japan Lipid Intervention Trial (J-LIT).

Hypercholesterolemic patients with type 2 diabetes mellitus are at increased risk of coronary heart disease (CHD); however, direct evidence is very limited in Japanese patients. The J-LIT is the first nationwide study conducted to assess the relationship between serum lipid levels and development of coronary events in Japanese hypercholesterolemic patients. We analyzed the coronary events in the J-LIT study subjects by having type 2 diabetes or not. Of the total 41,801 subjects without prior CHD who received open-label simvastatin, 5mg/day, 6554 (male 40.2%, age 57.8+/-7.8) subjects had type 2 diabetes, while 35,247 (male 30.0%, age 57.8+/-7.9) did not. In this analysis, relative coronary event risks based on a 0.26 mmol/l (10mg/dl) increase in low density lipoprotein-cholesterol (LDL-C), were similar between hypercholesterolemic subjects with and without type 2 diabetes (17.3% versus 19.4%). Although all subjects were treated with simvastatin, the subjects with type 2 diabetes have significantly more coronary events compared to the subjects without type 2 diabetes (1.80/1000 and 0.76/1000 patient-years, respectively). Given the results above, to reduce the risk of coronary events in Japanese patients with both hypercholesterolemia and type 2 diabetes, careful and strict cholesterol management is needed in addition to the control of blood glucose.

Effects of hypertension and type 2 diabetes mellitus on the risk of total cardiovascular events in Japanese patients with hypercholesterolemia: implications from the Japan Lipid Intervention Trial (J-LIT).

Hyperlipidemia, hypertension, and diabetes mellitus (DM) are well-established risk factors for cardiovascular disease. We analyzed the cardiovascular events in hyperlipidemic patients with or without DM who were administered open-labeled simvastatin in groups stratified by blood pressure level using data from the Japan Lipid Intervention Trial (J-LIT). Hyperlipidemic patients with DM (n=6,288) had significantly more cardiovascular events than those without DM (n=33,933). The incidence rates of total cardiovascular events in the Non-DM and DM groups were 15.40 and 25.76 per 1,000 patients for the 6-year period, respectively. The relative risk of total cardiovascular events in the DM vs. the Non-DM group was 1.68, and the relative risk was significantly higher in the DM than in the Non-DM group. The relative risks of total cardiovascular events were significantly higher in DM and Non-DM patients whose systolic blood pressure (SBP) was greater than or equal to 130 mmHg compared to that of Non-DM patients whose SBP was less than 130 mmHg, and in DM and Non-DM patients whose diastolic blood pressure (DBP) was greater than or equal to 80 mmHg compared to that of Non-DM patients whose DBP was less than 80 mmHg. In all groups stratified by SBP and DBP, relative risks of total cardiovascular events were higher in DM patients than in Non-DM patients. For patients with hypercholesterolemia and DM, blood pressure should be strictly controlled in order to prevent both coronary events and stroke. These results are in good agreement with the JNC 7 and the ESH/ESC guidelines for DM patients, which recommended that the SBP and DBP be less than 130 and 80 mmHg, respectively.

Polymorphisms of apolipoprotein e and methylenetetrahydrofolate reductase in the Japanese population.

AIM: The aim of this study is to analyze the effect of apolipoprotein E (apo E) and methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms on serum lipid and homocysteine levels in the general Japanese population. METHODS: We analyzed the polymorphisms in individuals randomly selected from among participants of Serum Lipid Survey 2000. RESULTS: The frequency of the epsilon2, epsilon3, and epsilon4 alleles of APOE was 4.2, 85.3, and 10.5%, respectively. Individuals with the genotype epsilon4/epsilon4 had the highest total and low-density lipoprotein (LDL) cholesterol levels, while those with epsilon2/epsilon2 had the lowest. Individuals with the epsilon2/epsilon2 and epsilon2/epsilon4 genotypes had higher remnant-like particles (RLP)-cholesterol levels than those with epsilon2epsilon3, epsilon3epsilon3, and epsilon3epsilon4. There was a trend for individuals with the epsilon2/epsilon4 and epsilon2/epsilon2 genotypes to have higher triglyceride levels, although the difference was not significant. The presence of the T allele in a MTHFR polymorphism (C667T) was associated with higher homocysteine levels, which is more prominent in men than in women. CONCLUSION: Thus in our large-scale analysis we have shown that RLP-cholesterol is better associated with, APOE genotype than triglyceride and the effect of the T allele on MTHFR polymorphism (C667T) homocysteine levels is more prominent in men than in women among Japanese.

Aliskiren, a novel oral renin inhibitor, provides dose-dependent efficacy and placebo-like tolerability in Japanese patients with hypertension.

Aliskiren is a novel orally active renin inhibitor for the treatment of hypertension. This study evaluated the antihypertensive efficacy, safety and tolerability of aliskiren in Japanese patients with hypertension. Forty hundred and fifty-five Japanese men and women with a mean sitting diastolic blood pressure of 95-110 mmHg were randomized to receive once-daily double-blind treatment for 8 weeks with aliskiren 75, 150 or 300 mg or placebo. Aliskiren produced significant, dose-dependent reductions in mean sitting diastolic blood pressure (p<0.0005 vs. placebo for each dose) and mean sitting systolic blood pressure (p<0.001 vs. placebo for each dose). The placebo-corrected reductions in mean sitting systolic/diastolic blood pressure were 5.7/4.0, 5.9/4.5 and 11.2/7.5 mmHg in the aliskiren 75, 150 and 300 mg groups, respectively. After 8 weeks' treatment, 27.8%, 47.8%, 48.2% and 63.7% of patients in the placebo and aliskiren 75, 150 and 300 mg groups, respectively, achieved a successful treatment response (diastolic blood pressure <90 mmHg and/or reduced by > or =10 mmHg from baseline; p<0.005 vs. placebo for each dose). Aliskiren treatment was well tolerated, with the incidence of adverse events reported in the active treatment groups (53-55%) being similar to that in the placebo group (50%). This study, which is the first to assess the antihypertensive efficacy and safety of aliskiren in Japanese patients with hypertension, demonstrates that the once-daily oral renin inhibitor aliskiren provides significant, dose-dependent reductions in blood pressure with placebo-like tolerability.

Prevalence of metabolic syndrome in the general Japanese population in 2000.

To determine the prevalence of metabolic syndrome in the Japanese general population, we analyzed data from a nationwide survey conducted in 2000. According to the Japanese new diagnostic criteria for metabolic syndrome in 2005, we analyzed 3,264 people aged from 20 to 79 (men, 1,917; women, 1,347) from the total participants. The incidence of metabolic syndrome was 7.8%. Men had a higher incidence (12.1%) than women (1.7%). Most of the women satisfying the criteria were 50 years old or over, while the incidence in men started to rise from their 30s. When we applied the criteria of Adult Treatment Panel III, the incidence was about 3-fold higher. In this population visceral obesity was associated with metabolic abnormalities, such as higher LDL-cholesterol, triglyceride, glucose, and blood pressure and lower HDL-cholesterol. Thus we determined the incidence of metabolic syndrome and each metabolic abnormality in the Japanese general population in 2000 and found an association of visceral obesity with metabolic abnormalities. Intervention to reduce the incidence of metabolic syndrome in Japan is necessary to reduce the risk of cardiovascular disease.

Bioinformatic Analysis of Plasma Apolipoproteins A-I and A-II Revealed Unique Features of A-I/A-II HDL Particles in Human Plasma.

Plasma concentration of apoA-I, apoA-II and apoA-II-unassociated apoA-I was analyzed in 314 Japanese subjects (177 males and 137 females), including one (male) homozygote and 37 (20 males and 17 females) heterozygotes of genetic CETP deficiency. ApoA-I unassociated with apoA-II markedly and linearly increased with HDL-cholesterol, while apoA-II increased only very slightly and the ratio of apoA-II-associated apoA-I to apoA-II stayed constant at 2 in molar ratio throughout the increase of HDL-cholesterol, among the wild type and heterozygous CETP deficiency. Thus, overall HDL concentration almost exclusively depends on HDL with apoA-I without apoA-II (LpAI) while concentration of HDL containing apoA-I and apoA-II (LpAI:AII) is constant having a fixed molar ratio of 2 : 1 regardless of total HDL and apoA-I concentration. Distribution of apoA-I between LpAI and LpAI:AII is consistent with a model of statistical partitioning regardless of sex and CETP genotype. The analysis also indicated that LpA-I accommodates on average 4 apoA-I molecules and has a clearance rate indistinguishable from LpAI:AII. Independent evidence indicated LpAI:A-II has a diameter 20% smaller than LpAI, consistent with a model having two apoA-I and one apoA-II. The functional contribution of these particles is to be investigated.

Suppressive effects of cacao liquor polyphenols (CLP) on LDL oxidation and the development of atherosclerosis in Kurosawa and Kusanagi-hypercholesterolemic rabbits.

We investigated the properties of cacao liquor polyphenols (CLP), which have an antioxidative effect on low-density lipoprotein (LDL) and an anti-atherosclerotic effect in the spontaneous familial hypercholesterolemic model, the Kurosawa and Kusanagi-hypercholesterolemic (KHC) rabbit. After 6 months of dietary administration of CLP at 1% (w/w) to the KHC rabbits, a higher total cholesterol concentration was observed in the treatment group compared to the control group. However, no other effects were noted in lipid profiles in plasma or lipoproteins. The plasma concentration of thiobarbituric acid reactive substances (TBARS), which is a lipid-peroxidation index, was significantly decreased 1 month after the start of CLP administration compared to that of the control group. The antioxidative effect of CLP on LDL was observed from 2 to 4 months of administration. The area of atherosclerotic lesions in the aorta in the CLP group (32.01+/-1.58%) was significantly smaller than that in the control group (47.05+/-3.29%), and the tissue cholesterol and TBARS concentrations were lower in the CLP group than in the control group. The anti-atherosclerotic effect of CLP was confirmed both rheologically and histopathologically. An in vitro study using KHC rabbit-derived LDL revealed that CLP significantly prolonged the lag time of LDL oxidation that was induced by a lipophilic azo-radical initiator, 2,2'-azobis(4-methoxy)-2,4-dimethylvaleronitrile (V-70), or Cu(2+) from a low concentration of 0.1 microg/mL. The antioxidative effect of CLP was superior to those of the well-known antioxidative substances, vitamin C, vitamin E and probucol. Therefore, CLP suppressed the generation of atherosclerosis, and its antioxidative effect appeared to have an important role in its anti-atherosclerotic activity.

The risk of cardiovascular events in Japanese hypertensive patients with hypercholesterolemia: sub-analysis of the Japan Lipid Intervention Trial (J-LIT) Study, a large-scale observational cohort study.

Coronary events and stroke are leading causes of death in Japan. However, the effects of hypertension on the risk of coronary events and stroke have not been well established in Japanese hypercholesterolemic patients. This study aimed to determine the relationship between the risk of coronary events or stroke and blood pressure and cholesterol levels during low-dose simvastatin treatment using data from the Japan Lipid Intervention Trial (J-LIT) study (a large scale nationwide cohort study). In the present study, 47,294 hypercholesterolemic patients were treated with open-labeled simvastatin (5 to 10 mg/day) for 6 years by a large number of physicians in a clinical setting. The adjusted incidence rates of coronary events in males and females were 8.9 and 2.3 and those of stroke were 17.6 and 11.3/1000 patients during the 6-year period, respectively. The incidence rate of stroke was higher than that of coronary events in both males and females. An obvious sex difference was observed in terms of the incidence of coronary events. The risk of coronary events, stroke, and total cardiovascular events were increased, with elevations in blood pressure observed in patients treated for hypercholesterolemia. The risk of total cardiovascular events in the groups exhibiting less lipid control increased, with lower blood pressure levels than those of the well-controlled group. For patients with hypercholesterolemia and hypertension, blood pressure should be strictly controlled in order to prevent both coronary events and stroke, and the serum total cholesterol levels should be maintained at low levels as well.

Suppressive effect of cocoa powder on atherosclerosis in Kurosawa and Kusanagi-hypercholesterolemic rabbits.

We investigated the suppressive effect of cocoa powder (cacao polyphenol content: 7.8%) on atherosclerosis in a spontaneous familial hypercholesterolemic model, Kurosawa and Kusanagi-hypercholesterolemic (KHC) rabbits. Six-month dietary administration of cocoa powder had no effects on body weight, hematology or blood chemistry parameters or a lipid profile in KHC rabbits. Antioxidative activity of low-density lipoprotein (LDL) was observed in the 2nd month and 3rd month of administration. Thiobarbituric acid reactive substances (TBARS), the marker of lipid peroxidation, in plasma were decreased in the cocoa powder treated group from the 2nd month of administration during the study period compared to that in the control group. The area of atherosclerotic lesions in th aorta was significantly smaller in the cocoa powder group (30.87%) than in the control (52.39%). Tissue cholesterol content also tended to decrease. Distensibility of the aortic wall was improved significantly in the cocoa powder treated group due to decreases in fatty streaks and intimal thickening compared to that in the control group. These results suggest that cocoa powder has suppressive effect on development of atherosclerotic lesions. We consider that antioxidative activity of polyphenols rich in cocoa powder may be a key factor for the anti-atherosclerotic effect.

Serum lipid survey and its recent trend in the general Japanese population in 2000.

To determine the recent serum lipid levels and other serum variables in the general Japanese population and trends in their changes over the past 40 years, a nationwide survey of serum lipid levels was conducted in 36 institutes from various districts around Japan in 2000. The total number of subjects was 12,839, aged 4 through 99 years. The mean total cholesterol level was 201 mg/dl; 202 mg/dl in men and 200 mg/dl in women. The mean HDL-cholesterol level was 59 mg/dl; 55 mg/dl in men and 65 mg/dl in women. The mean LDL-cholesterol level was 118 mg/dl; 121 mg/dl in men and 115 mg/dl in women. The mean triglyceride level was 118 mg/dl; 136 mg/dl in men and 92 mg/dl in women. The total cholesterol level slightly increased by 5 mg/dl in 10 years. Although the triglyceride level in women did not change, the triglyceride level in men increased over 10 years, especially in the 30s through 70s age bracket, indicating a possible increase in metabolic syndromes in the future. The present results will become the standard serum lipid level data for the Japanese people, and succeeding 10-year surveys will clarify the trends of lipid levels in this country.

Polymorphisms in four genes related to triglyceride and HDL-cholesterol levels in the general Japanese population in 2000.

We studied the association of six common polymorphisms of four genes related to lipid metabolism with serum lipid levels. We selected single-nucleotide polymorphisms (SNPs) in the genes for cholesteryl ester transfer protein (CETP), lipoprotein lipase (LPL), hepatic lipase (LIPC), and apolipoprotein CIII (APOC3), and studied 2267 individuals randomly selected from the participants of Serum Lipid Survey 2000. There was a significant association of CETP polymorphism (D442G, Int14 +1 G --> A, and TaqIB), LPL polymorphism (S447X), and LIPC polymorphism (-514 --> CT) with HDL-cholesterol levels. We also found a significant association of LPL polymorphism (S447X) and APOC3 polymorphism (SstI) with triglyceride levels. This is the largest database showing the association of common genetic variants in lipid metabolism with serum lipid levels in the general Japanese population. Further study is necessary to elucidate the role of these gene polymorphisms in cardiovascular events.

Eicosapentaenoic acid inhibits CSF-induced human monocyte survival and maturation into macrophage through the stimulation of H2O2 production.

Human studies suggest a beneficial effect of eicosapentaenoic acid (EPA)-supplemented diets on atherosclerotic and atherothrombotic disorders as well as autoimmune and inflammatory diseases and tumors. The effects of EPA on human monocyte survival and maturation into macrophage are not yet known. We studied the effects of EPA on the survival and development into macrophage of human monocyte treated with colony-stimulating factor (CSF). We have found that EPA induces cell death of the monocyte via apoptosis, even in the presence of M-CSF or GM-CSF, and inhibits differentiation from the monocyte to macrophage by inducing H2O2 production. In contrast to the effect of EPA on monocytes, EPA did not induce cell death of monocyte-derived macrophages. Such an apoptosis inducing effect on monocytes by EPA may contribute to the efficacy of EPA in atherosclerosis and autoimmune diseases.

Antioxidant activity of various teas against free radicals and LDL oxidation.

Tea is a widely consumed beverage throughout the world. We assessed the antioxidant activity of six teas, including the aqueous extracts of green tea and oolong tea (Camellia sinensis), tochu (Eucommia ulmoides), Gymnema sylvestre, Japanese mugwort (Artemisia princeps), and barley (Hordeum vulgare), against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and LDL oxidation, and examined the association of LDL oxidizability with the plasma catechin levels in 10 healthy volunteers with a single dose of 5 g green tea powder. In vitro, the inhibitory effects of DPPH radicals and LDL oxidation were found to be strongest in the extract of green tea and weakest in that of barley. After the ingestion of green tea powder, the lag time increased from basal 52.2 +/- 4.1 to 60.3 +/- 4.2 min at 1 h and 59.5 +/- 4.1 min at 2 h, and then returned to the baseline lag time (51.9 +/- 1.4 at 4 h and 52.1 +/- 4.7 min at 6 h). Regarding the plasma catechin levels, epigallocatechingallate and epicatechingallate significantly increased from basal 3.7 +/- 1.3 and 0.8 +/- 0.8 ng/mL to 65.7 +/- 11.6 and 54.6 +/- 12.6 ng/mL at 1 h, and 74.4 +/- 18.6 and 49.4 +/- 7.1 ng/mL at 2 h, respectively. Green tea therefore showed the strongest antioxidant activity among the six different teas, and the inhibitory effects of green tea on LDL oxidation depended on the plasma catechin levels.

Chlorella ingestion suppresses resistin gene expression in peripheral blood cells of borderline diabetics.

BACKGROUND & AIMS: Type 2 diabetes can lead to arteriosclerosis, renal damage, retinopathy, and several other serious complications. To prevent or delay the progression of this disease, considerable attention has been paid to improve exercise and dietary habits. Chlorella ingestion can reportedly reduce high blood glucose and cholesterol levels in mice and humans, although no studies have critically evaluated the effects of Chlorella on human borderline diabetics. Thus, we conducted a randomized, double-blind placebo-controlled test with volunteer borderline diabetics. METHODS: We recruited 57 subjects and randomly divided into a Chlorella ingestion group (n = 28) and a Placebo ingestion group (n = 29). Blood samples were collected every 4 weeks for laboratory tests. Gene expression analyses using peripheral blood cell RNA were performed before and 12 weeks after the trial. RESULTS: A total of 252 genes showed changed expression levels between these two groups. Six of these were type 2 diabetes-associated genes, including resistin, an insulin resistance inducer that exhibited markedly reduced expression with Chlorella ingestion (P = 0.01). Resistin mRNA expression significantly correlated with changes in HbA1c and TNF-α and IL-6 levels, all of which are strongly associated with glucose metabolism and/or inflammation. CONCLUSIONS: Chlorella ingestion may be useful in preventing or ameliorating the course of type 2 diabetes development. In addition, gene expression analysis may be a means to investigate the effects of foods and supplements in humans.

Sequential change in physicochemical properties of LDL during oxidative modification.

Oxidized LDL is thought to be a highly atherogenic lipoprotein. Structural background of this pathogenesis, however, has not yet been well defined. Physicochemical characterization of this lipoprotein is still controversial, which therefore makes it difficult to take a mechanistic approach to its atherogenicity. We thus conducted investigation of time-dependent changes in chemical compositions and alternation of physical properties of LDL in detail during its oxidation induced by human embryonic endothelial cells and copper ions. The oxidation caused hydrolysis of glycerolipids being demonstrated as decrease of triglyceride and choline-phospholipid and increase of lysophosphatidylcholine. Fragmentation of apoB was also induced while over-all protein components stayed with the particles. The density of the particles continuously shifted to higher fractions for all the particles to reach d ≥ 1.044 after 10h incubation. The average diameter of LDL, however, decreased from 28.1 nm to 25.6 nm by 5h and increased to 27.1 nm towards 20 h incubation with the increase of discoid particles. These dynamic changes can be interpreted by losing fatty acyl group from the core lipid components perhaps due to oxidative degradation and by increase of surface lysophosphatidylcholine to cause remodeling of the particles.