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BACKGROUND: Homozygous familial hypercholesterolemia is characterized by premature cardiovascular disease caused by markedly elevated levels of low-density lipoprotein (LDL) cholesterol. This disorder is associated with genetic variants that result in virtually absent (null-null) or impaired (non-null) LDL-receptor activity. Loss-of-function variants in the gene encoding angiopoietin-like 3 (ANGPTL3) are associated with hypolipidemia and protection against atherosclerotic cardiovascular disease. Evinacumab, a monoclonal antibody against ANGPTL3, has shown potential benefit in patients with homozygous familial hypercholesterolemia. METHODS: In this double-blind, placebo-controlled, phase 3 trial, we randomly assigned in a 2:1 ratio 65 patients with homozygous familial hypercholesterolemia who were receiving stable lipid-lowering therapy to receive an intravenous infusion of evinacumab (at a dose of 15 mg per kilogram of body weight) every 4 weeks or placebo. The primary outcome was the percent change from baseline in the LDL cholesterol level at week 24. RESULTS: The mean baseline LDL cholesterol level in the two groups was 255.1 mg per deciliter, despite the receipt of maximum doses of background lipid-lowering therapy. At week 24, patients in the evinacumab group had a relative reduction from baseline in the LDL cholesterol level of 47.1%, as compared with an increase of 1.9% in the placebo group, for a between-group least-squares mean difference of -49.0 percentage points (95% confidence interval [CI], -65.0 to -33.1; P

Aims Age-related cardiac hypertrophy and subsequent heart failure are predicted to become increasingly serious problems in aging populations. Progranulin (PGRN) deficiency is known to be associated with accelerated aging in the brain. We aimed to evaluate the effects of PGRN deficiency on cardiac aging, including left ventricular hypertrophy. Methods and results Echocardiography was performed on wild-type (WT) and PGRN-knockout (KO) mice every 3 months from 3 to 18 months of age. Compared to that of WT mice, PGRN KO mice exhibited age-dependent cardiac hypertrophy and cardiac dysfunction at 18 months. Morphological analyses showed that the heart weight to tibia length ratio and cross-sectional area of cardiomyocytes at 18 months were significantly increased in PGRN KO mice relative to those in WT mice. Furthermore, accumulation of lipofuscin and increases in senescence markers were observed in the hearts of PGRN KO mice, suggesting that PGRN deficiency led to enhanced aging of the heart. Enhanced complement C1q (C1q) and activated β-catenin protein expression levels were also observed in the hearts of aged PGRN KO mice. Treatment of PGRN-deficient cardiomyocytes with C1q caused β-catenin activation and cardiac hypertrophy. Blocking C1q-induced β-catenin activation in PGRN-depleted cardiomyocytes attenuated hypertrophic changes. Finally, we showed that C1 inhibitor treatment reduced cardiac hypertrophy and dysfunction in old KO mice, possibly by reducing β-catenin activation. These results suggest that C1q is a crucial regulator of cardiac hypertrophy induced by PGRN ablation. Conclusion The present study demonstrates that PGRN deficiency enhances age-related cardiac hypertrophy via C1q-induced β-catenin activation. PGRN is a potential therapeutic target to prevent cardiac hypertrophy and dysfunction.

Tryptophan (TRP), a precursor of serotonin is believed to have an antidepressant effect. The pathway for brain uptake of TRP is shared by other large neutral amino acids; therefore, the best time to take TRP may be between meals. No previous study has, however, designated the time of TRP dosing to improve mood. Further, the effects of TRP on autonomic nervous system (ANS) activity are unclear. This study investigated the effects of TRP, vitamin B6, and nicotinamide-containing supplements loading between meals on mood and ANS activity in depressive young adults. Thirty depressive young adults were randomly allocated to receive TRP, vitamin B6, and nicotinamide-containing supplements or a placebo supplements twice daily between meals for 7 d. Mood was measured using the Center for Epidemiologic Studies Depression Scale (CES-D) and the Profile of Mood States (POMS). ANS activities were analyzed by heart rate variability power spectral analysis. Blood samples were assayed for plasma total TRP concentration. For analysis, TRP and placebo groups were further classified into two subgroups according to CES-D score (mild to moderate vs. severe depressive symptoms). The CES-D score significantly improved following both treatments in the severe depression subgroups, while the POMS depression score was significantly improved only in the TRP severe depression subgroup. There was no significant change in ANS activity or plasma total TRP in any group. TRP, vitamin B6, and nicotinamide-containing supplements loading between meals can quickly improve depressed mood in quite low dose in young adults with severe subclinical depression.

Fibroblast growth factor (FGF) 21 has various functions, including glucose and lipid metabolism. This cross-sectional study aimed to investigate specific conditions that might influence the functions of FGF21. 398 men who underwent a health examination were enrolled in this study. Physical and biochemical parameters and information on several lifestyle behaviors were obtained from all subjects. FGF21 levels correlated with age, body mass index (BMI), waist circumference (WC), systolic blood pressure (SBP), diastolic blood pressure (DBP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transpeptidase (γ-GTP), uric acid, total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDLC), fasting plasma glucose (FPG), and HbA1c. Moreover, FGF21 levels were significantly associated with lifestyle behaviors, including smoking status and breakfast and alcohol consumption frequency. Multivariable regression analysis showed that age, ALT, γ-GTP, smoking status, and breakfast and alcohol consumption frequency were independent variables for FGF21 levels. Assessment among the non-obese and obese groups showed that FGF21 levels correlated with WC, SBP, and TC only in the non-obese group. Thus, serum FGF21 levels were affected by several factors, including lifestyle behaviors, age, and liver function. To assess the functions of FGF21 in individuals, considering these factors would be essential.

CD36 is one of the important transporters of long-chain fatty acids (LCFAs) in the myocardium. We previously reported that CD36-deficient patients demonstrate a marked reduction of myocardial uptake of LCFA, while myocardial glucose uptake shows a compensatory increase, and are often accompanied by cardiomyopathy. However, the molecular mechanisms and functional role of CD36 in the myocardium remain unknown.The current study aimed to explore the pathophysiological role of CD36 in the heart. Methods: Using wild type (WT) and knockout (KO) mice, we generated pressure overload by transverse aortic constriction (TAC) and analyzed cardiac functions by echocardiography. To assess cardiac hypertrophy and fibrosis, histological and molecular analyses and measurement of ATP concentration in mouse hearts were performed.By applying TAC, the survival rate was significantly lower in KO than that in WT mice. After TAC, KO mice showed significantly higher heart weight-to-tibial length ratio and larger cross-sectional area of cardiomyocytes than those of WT. Although left ventricular (LV) wall thickness in the KO mice was similar to that in the WT mice, the KO mice showed a significant enlargement of LV cavity and reduced LV fractional shortening compared to the WT mice with TAC. A tendency for decreased myocardial ATP concentration was observed in the KO mice compared to the WT mice after TAC operation.These data suggest that the LCFA transporter CD36 is required for the maintenance of energy provision, systolic function, and myocardial structure.

Aims: HDL particles have various anti-atherogenic functions, whereas HDL from atherosclerotic patients was demonstrated to be dysfunctional. One possible mechanism for the formation of dysfunctional HDL is the oxidation of its components. However, oxidized HDLs (Ox-HDLs) remain to be well investigated due to lack of reliable assay systems. Methods: We have developed a novel sandwich enzyme-linked immunosorbent assay (ELISA) for Ox-HDL by using the FOH1a/DLH3 antibody, which can specifically recognize oxidized phosphatidylcholine, a major component of HDL phospholipid (HDL-PL). We defined forced oxidation of 1 mg/L HDL-PL as 1 U/L Ox-HDL. We assessed serum Ox-HDL levels of normolipidemic healthy subjects ( n =94) and dyslipidemic patients ( n =177). Results: The coefficients of variation of within-run and between-run assays were 12.5% and 13.5%. In healthy subjects, serum Ox-HDL levels were 28.5±5.0 (mean±SD) U/L. As Ox-HDL levels were moderately correlated with HDL-PL (r=0.59), we also evaluated the Ox-HDL/HDL-PL ratio, which represents the proportion of oxidized phospholipids in HDL particles. In dyslipidemic patients, Ox-HDL levels were highly variable and ranged from 7.2 to 62.1U/L, and were extremely high (50.4±13.3U/L) especially in patients with hyperalphalipoproteinemia due to cholesteryl ester transfer protein deficiency. Regarding patients with familial hypercholesterolemia, those treated with probucol, which is a potent anti-oxidative and anti-hyperlipidemic drug, showed significantly lower Ox-HDL (16.2±5.8 vs. 30.2±5.4, p ＜0.001) and Ox-HDL/HDL-PL ratios (0.200±0.035 vs. 0.229±0.031, p =0.015) than those without probucol. Conclusion: We have established a novel sandwich ELISA for Ox-HDL, which might be a useful and easy strategy to evaluate HDL functionality, although the comparison study between this Ox-HDL ELISA and the assay of HDL cholesterol efflux capacity remains to be done. Our results indicated that probucol treatment may be associated with lower Ox-HDL levels.

Non-alcoholic fatty liver disease is strongly associated with obese and type 2 diabetes. It has been reported that an oxidized cholesterol, 7-ketocholesterol (7KC), might cause inflammatory response in macrophages and plasma 7KC concentration were higher in patients with cardiovascular diseases or diabetes. Therefore, we have decided to test whether small amount of 7KC in diet might induce hepatic steatosis and inflammation in two types of obese models. We found that addition of 0.01% 7KC either in chow diet (CD, regular chow diet with 1% cholesterol) or western type diet (WD, high fat diet with 1% cholesterol) accelerated hepatic neutral lipid accumulation by Oil Red O staining. Importantly, by lipid extraction analysis, it has been recognized that triglyceride rather than cholesterol species was significantly accumulated in CD+7KC compared to CD as well as in WD+7KC compared to WD. Immunostaining revealed that macrophages infiltration was increased in CD+7KC compared to CD, and also in WD+7KC compared to WD. These phenotypes were accompanied by inducing inflammatory response and downregulating fatty acid oxidation. Furthermore, RNA sequence analysis demonstrated that 7KC reduced expression of genes which related to autophagy process. Levels of LC3-II protein were decreased in WD+7KC compared to WD. Similarly, we have confirmed the effect of 7KC on acceleration of steatohepatitis in db/db mice model. Collectively, our study has demonstrated that small amount of dietary 7KC contributed to accelerate hepatic steatosis and inflammation in obese mice models.

Electrical muscle stimulation (EMS) has been shown to increase muscle strength and mass, suggesting that it can be used for the treatment of sarcopenia. We herein present a detailed review of the physiological changes induced by EMS. Only human experimental and clinical studies were selected as reference articles for this review. Low-frequency stimulation appears to have greater effects on strengthening, while high frequency favors an increase in muscle mass. EMS also promotes compositional changes of the muscle fibers and improvements in the oxidative enzymatic activity and glucose uptake. Considering that structural changes towards type II muscle fibers and their motor units have an important role in the loss of muscle strength and that the response to muscular training is based on the capacity to increase muscle activation, an intervention protocol using EMS should focus on stimulating type II muscle fibers, rather than on inducing muscle hypertrophy.

Observational studies have shown that serum HDL-C levels are negatively correlated with cardiovascular events. HDL particles have various kinds of anti-atherogenic functions such as reverse cholesterol transport. By contrast, HDL from atherosclerotic patients are demonstrated to be dysfunctional or

Aim The morbidity of cardiovascular disease in patients with type 2 diabetes mellitus (DM) deteriorates in combination with dyslipidemia. The accumulation of remnant lipoproteins in patients with fasting and postprandial hypertriglyceridemia is highly atherogenic. The current study investigated whether the dipeptidyl peptidase-4 inhibitor sitagliptin ameliorates dyslipidemia and hyperglycemia. Methods We enrolled 38 patients with type 2 DM (20 males and 18 females, 65.7±9.9 years old, HbA1c levels ＜8.4%), and all patients gave written informed consent. Sitagliptin (50 mg/day) was added to current antidiabetic treatments and increased to 100 mg/day to achieve low HbA1c levels (＜7.4%). Glucose and lipoprotein metabolism profiles were analyzed at 0, 4, and 12 weeks after sitagliptin administration. Results Sitagliptin significantly decreased fasting levels of triglyceride (TG) (161±90 vs. 130±66 mg/dl, p＜0.01) and non-HDL-C (129±29 vs. 116±20 mg/dl, p＜0.01) in combination with glucose (150±47 vs. 129±27 mg/dl, p＜0.01) and HbA1c (7.1±0.6 vs. 6.6±0.7 mg/dl, p＜0.001). Sitagliptin also significantly decreased the fasting levels of apolipoprotein (apo) B-48 (7.8±6.7 vs. 5.6±4.0 µg/ml, p＜0.01), remnant lipoprotein cholesterol (15.3±9.5 vs. 12.0±7.9 mg/dl, p＜0.05) and other apolipoproteins, such as apoB, apoC-II, apoC-III, and apoE. Analyses of the lipoprotein profiles of fasting sera revealed that sitagliptin significantly decreased cholesterol and TG levels of lipoprotein fractions in the size of very low density lipoprotein and low density lipoprotein. Conclusions These findings indicated that sitagliptin administration ameliorated the lipid and lipoprotein profiles in patients with diabetes, which may be due to the decrease in atherogenic remnant lipoproteins (UMIN#000013218).

Reduced clearance of lipoproteins by HDL scavenger receptor class B1 (SR-B1) plays an important role in occlusive coronary artery disease. However, it is not clear how much microvascular dysfunction contributes to ischemic cardiomyopathy. Our aim was to determine the distribution of vascular dysfunction in vivo in the coronary circulation of male mice after brief exposure to Paigen high fat diet, and whether this vasomotor dysfunction involved nitric oxide (NO) and or endothelium derived hyperpolarization factors (EDHF). We utilised mice with hypomorphic ApoE lipoprotein that lacked SR-B1 (SR-B1−/−/ApoER61h/h, n = 8) or were heterozygous for SR-B1 (SR-B1+/−/ApoER61h/h, n = 8) to investigate coronary dilator function with synchrotron microangiography. Partially occlusive stenoses were observed in vivo in SR-B1 deficient mice only. Increases in artery-arteriole calibre to acetylcholine and sodium nitroprusside stimulation were absent in SR-B1 deficient mice. Residual dilation to acetylcholine following L-NAME (50 mg/kg) and sodium meclofenamate (3 mg/kg) blockade was present in both mouse groups, except at occlusions, indicating that EDHF was not impaired. We show that SR-B1 deficiency caused impairment of NO-mediated dilation of conductance and microvessels. Our findings also suggest EDHF and prostanoids are important for global perfusion, but ultimately the loss of NO-mediated vasodilation contributes to atherothrombotic progression in ischemic cardiomyopathy.

Aims CD36 is an important transporter of long-chain fatty acids (LCFAs) in the myocardium. As we have reported previously, CD36-deficient patients demonstrate a marked reduction in myocardial uptake of 123I-15-(p-iodophenyl)-(R, S)-methyl pentadecanoic acid (BMIPP), which is an analog of LCFAs, while myocardial 18 F-fluorodeoxy-glucose (FDG) uptake is increased. However, it has not been clarified whether energy provision is preserved in patients with CD36 deficiency. The aims of the current study were to investigate the myocardial uptake of glucose and alterations in myocardial metabolites in wild-type (WT) and CD36 knockout (KO) mice. Methods and results High-resolution positron emission tomography (PET) demonstrated markedly enhanced glucose uptake in KO mouse hearts compared with those of WT mice in real-time. The myocardial protein expression of glucose transporter protein 1 (GLUT1) was significantly enhanced in KO mice compared to WT mice, whereas that of GLUT4 was not altered. While the myocardial expression of genes involved in fatty acid metabolism did not increase in KO mice, that of genes related to glucose utilization compensatorily increased in KO mice. The metabolomic analysis of cardiac tissues revealed that the myocardial concentrations of ATP and phosphocreatine were maintained, even in KO mice. The concentration of 3-hydroxybutyric acid and mRNA expression of hydroxybutyrate dehydrogenase in the heart were significantly higher in KO than in WT mice. Conclusion These data suggest that high-energy phosphate might be preserved by the increased utilization of glucose and ketone bodies in CD36KO mouse hearts under conditions of deficient LCFA uptake.

Background Men and women react differently to some disease states, and women are reported to be more sensitive than men to the toxic effects of smoking. We examined the serum concentration of Klotho-related molecules, α-Klotho (αKl) and fibroblast growth factor (FGF)-21, and the influence of smoking on these molecules in both sexes. Methods Subjects included 90 men and 140 women in good health who underwent a health examination. Results Among male subjects, serum concentrations of FGF-21, soluble sαKl, and inflammation-related cytokine interleukin (IL)-6 were significantly higher in smokers than in never-smokers. In females, serum concentrations of FGF-21 and IL-6 were significantly higher in smokers than in never-smokers; however, sαKl concentrations were slightly lower in smokers than in never-smokers. Serum concentrations of sαKl were correlated with smoking status and IL-6 only in male subjects, suggesting an anti-inflammatory effect of sαKl only in men. Serum concentrations of FGF-21 were correlated with the concentrations of total cholesterol, triglycerides, and HbA1c, which are important factors of metabolic disorders in females, suggesting that metabolic disorders in female smokers may be more serious than that in male smokers. Conclusions Klotho-related molecules showed a differential association and response to smoking between men and women.

Aims Fasting and postprandial hypertriglyceridemia (PHTG) are caused by the accumulation of triglyceride (TG)-rich lipoproteins and their remnants, which have atherogenic effects. Fibrates can improve fasting and PHTG; however, reduction of remnants is clinically needed to improve health outcomes. In the current study, we investigated the effects of a novel selective peroxisome proliferator-activated receptor α modulator (SPPARMα), K-877 (Pemafibrate), on PHTG and remnant metabolism. Methods Male C57BL/6J mice were fed a high-fat diet (HFD) only, or an HFD containing 0.0005% K-877 or 0.05% fenofibrate, from 8 to 12 weeks of age. After 4 weeks of feeding, we measured plasma levels of TG, free fatty acids (FFA), total cholesterol (TC), HDL-C, and apolipoprotein (apo) B-48/B-100 during fasting and after oral fat loading (OFL). Plasma lipoprotein profiles after OFL, which were assessed by high performance liquid chromatography (HPLC), and fasting lipoprotein lipase (LPL) activity were compared among the groups. Results Both K-877 and fenofibrate suppressed body weight gain and fasting and postprandial TG levels and enhanced LPL activity in mice fed an HFD. As determined by HPLC, K-877 and fenofibrate significantly decreased the abundance of TG-rich lipoproteins, including remnants, in postprandial plasma. Both K-877 and fenofibrate decreased intestinal mRNA expression of ApoB and Npc1l1; however, hepatic expression of Srebp1c and Mttp was increased by fenofibrate but not by K-877.Hepatic mRNA expression of apoC-3 was decreased by K-877 but not by fenofibrate. Conclusion K-877 may attenuate PHTG by suppressing the postprandial increase of chylomicrons and the accumulation of chylomicron remnants more effectively than fenofibrate.

Objective To clarify the probability of low serum testosterone level as a risk factor for metabolic syndrome (MS) in middle-aged men, we measured serum total testosterone (TT) and assessed several metabolic factors because the direct risk for MS has not been investigated fully in men. Methods This study comprised 1150 men aged ≥30 years. Physical and laboratory variables were assessed. Analyses were conducted to determine the association between serum TT level and incidence risk of MS and MS factors by a separate logistic regression model. Results Mean (± standard deviation [SD]) serum TT level was 5.4 ± 1.7 ng/mL in the 1150 men, and only 92 men (8.0%) were classified as having MS by the Japanese criteria. In age-adjusted analyses, higher levels of serum TT were independently associated with a lower risk of MS (odds ratio, per SD decrement of TT, 2.3; 95% confidence interval [CI], 1.7-2.9). MS risk increased by lower quintile of TT: ORs were 15.1 (95% CI, 4.6-50.0) for first quintile, 8.8 (95% CI, 2.6-29.9) for second quintile, 5.8 (95% CI, 1.7-20.5) for third quintile, and 5.0 (95% CI, 1.4-17.9) for fourth quintile compared with highest quintile of TT. Age-adjusted ORs for the incidence of dichotomous components of MS per SD decrement of TT were 1.8 (95% CI, 1.5-2.3) for waist circumference, 1.6 (95% CI, 1.1-2.2) for dyslipidemia, and 1.5 (95% CI, 1.2-1.8) for hypertension. Conclusion We found that higher probability of MS was associated with lower levels of serum TT level in relatively healthy middle-aged Japanese men.

Aims Progranulin (PGRN) is a multifunctional protein known to be involved in inflammation. However, the relation between PGRN and atherosclerosis remains elusive. The aim of this study was to define the role of PGRN in the development of atherosclerosis. Methods and results First, we checked the expression levels of PGRN in human atherosclerotic plaques. Immunohistochemical analysis showed that PGRN is strongly expressed in foam cells of atherosclerotic plaques. We also found that PGRN is expressed more abundantly in macrophages than in the smooth muscle cells of atherosclerotic lesions in ApoE−/− mice fed a high-fat diet for 12 weeks. Next, PGRN−/−ApoE−/− mice were generated to investigate the effect of PGRN on the development of atherosclerosis. PGRN−/−ApoE−/− mice exhibited severe atherosclerotic lesions compared with PGRN+/+ApoE−/− mice, despite their anti-atherogenic lipid profile. These results are partly due to enhanced expression of inflammatory cytokines, adhesion molecules, and decreased expression of endothelial nitric oxide synthase. In addition, lack of PGRN leads to accumulate excessive cholesterol in the macrophages and alter HDL-associated proteins. Conclusion PGRN seems to be involved in the pathogenesis of atherosclerosis, possibly by various anti-atherogenic effects, including modulation of local and/or systemic inflammation.

Aim: Remnant lipoproteins are atherogenic and are accumulated in patients with type III hyperlipidemia (HL). Although type III HL is diagnosed by phenotyping apolipoprotein (apo) E, this procedure is time-consuming and inconvenient for routine clinical use. Clinical indices for screening type III HL in untreated HL patients have been proposed; however, in clinical settings, HL patients are promptly treated with lipid-lowering agents without diagnosing the underlying cause. We investigated whether existing clinical indices for screening type III HL as well as the apo B-48/triglyceride (TG) ratio, which was suggested to be related to the accumulation of small chylomicron (CM) remnants, are useful after the initiation of lipid-lowering therapies.Methods: In 25 normolipidemic subjects and 191 treated HL patients (type I, n =6; IIa, 62; IIb, 66; III, 12; IV, 22; and V, 23) from Osaka University Hospital and related hospitals, fasting low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), TG, and apolipoproteins were measured and clinical indices were evaluated statistically.Results: Apo B-48 levels were significantly higher in patients with type I, III, and V HL, and TG levels were significantly higher in patients with type I and V HL. The apo B-48/TG ratio was significantly higher only in patients with type III HL compared with other types of HL (p

In the present study, we measured carotid artery intima-media thickness (CIMT) and assessed several metabolic factors in middle-aged healthy Japanese men to clarify the relation between testosterone and atherosclerosis. The study comprised 176 male employees aged ≥40 years who visited Osaka University Healthcare Center for their annual health examinations. Serum total testosterone (TT) concentration was measured using radioimmunoassay (RIA) and serum free testosterone concentration was measured using analog ligand RIA (aFT). A multivariate model adjusted for age, body mass index, mean arterial pressure and treatment for hypertension demonstrated a significant association between aFT and CIMT. Even after adjustment for other clinically relevant factors, the significant association between aFT and CIMT was not attenuated. After adjustment for all other clinically relevant factors, both univariate and multivariate models ascertained the stepwise association that a level of aFT of ≤10.0 pg/mL was significantly associated with CIMT. However, the association between TT and CIMT was not significant in either univariate or multivariate models. We conclude that our finding showing that low serum aFT level is an influencing and independent risk factor for CIMT is of value in the clinical setting because no other studies, to our knowledge, have conducted multivariate analyses using the various metabolic factors included in the present analyses.

Background: Smoking is a major risk factor for cardiovascular disease. Also, inflammatory activation and metabolic disorder are the mediators of smoking-induced atherosclerotic progression. The aim of the present study was to investigate whether current smoking and smoking cessation alter inflammatory or metabolic status and affect subclinical atherosclerosis in apparently healthy men. Methods and Results: Classical risk factors and smoking habit were evaluated in 354 men who completed health examinations annually without any current medications. Carotid intima-media thickness (IMT) was followed for 27.1±4.5 months. At baseline, both maximum and mean IMT significantly changed during 2-year follow-up. They tended to increase along with progression of smoking habit, with significantly greater maximum IMT in current smokers compared with never smokers. Both maximum and mean IMT significantly changed during 2-year follow-up, and tended to increase with progression of smoking habit, with maximum IMT being greatest for current smokers. Past smokers tended to have greater IMT increase than never smokers. Among smoking habit and some atherosclerotic risk markers that showed significant correlation with maximum IMT increase, stepwise regression showed that smoking habit and serum low-density lipoprotein-cholesterol (LDL-C) level were the only independent predictors. Conclusions: Significant 2-year progression of subclinical atherosclerosis was associated with continuous smoking and LDL-C. This was only partly moderated in past smokers despite complete reversal of inflammatory activation, suggesting another crucial factor for inhibiting accelerated progression of subclinical atherosclerosis in men. (Circ J 2012; 76: 2884 – 2891)

Objective We previously reported that patients with cholesteryl ester transfer protein (CETP) deficiency (CETP-D) have a higher prevalence of atherosclerotic cardiovascular disease, in spite of increased HDL-C levels. However, characterization of HDL in CETP-D has not been well described. Therefore, we examined HDL particle number (PN) rather than HDL-C level. Approach and results Nine patients with CETP-D and 9 normolipidemic subjects were enrolled. We performed gel permeation high-performance liquid chromatography (GP-HPLC) analysis, determined the cholesterol and triglyceride composition of all lipoprotein subclasses, and calculated the PN of each subclass, which consisted of 3 VLDL (large, medium, and small), 4 LDL (large, medium, small, and very small), and 5 HDL (very large, large, medium, small, and very small) subclasses. The PNs of large and medium LDL were significantly lower in CETP-D than that in healthy subjects (0.66- and 0.63-fold decrease, respectively; p

Objectives— Adiponectin is recognized as an antidiabetic, antiatherosclerotic, and anti-inflammatory protein derived from adipocytes. However, the role of adiponectin in cardiac fibrosis remains uncertain. We herein explore the effects of adiponectin on cardiac fibrosis induced by angiotensin II (Ang II). Methods and Results— Wild-type (WT), adiponectin knockout (Adipo-KO), and PPAR-α knockout (PPAR-α-KO) mice were infused with Ang II at 1.2 mg/kg/d. Severe cardiac fibrosis and left ventricular dysfunction were observed in Ang II–infused Adipo-KO mice compared to WT mice. Adenovirus-mediated adiponectin treatment improved the above phenotypes and the dysregulation of reactive oxygen species (ROS)-related mRNAs in Adipo-KO mice, whereas such amelioration was not observed in PPAR-α-KO mice despite adiponectin accumulation in heart tissue. In cultured cardiac fibroblasts, adiponectin improved the reduction of AMP-activated protein kinase (AMPK) activity and elevation of extracellular signal–regulated kinase 1/2 (ERK1/2) activity induced by Ang II. Adiponectin significantly enhanced PPAR-α activity, whereas the adiponectin-dependent PPAR-α activation was diminished by Compound C, an inhibitor of AMPK. Conclusion— The present study suggests that adiponectin protects against Ang II–induced cardiac fibrosis possibly through AMPK-dependent PPAR-α activation.

Plasma high density lipoprotein (HDL)-cholesterol levels are inversely correlated with the incidence of cardiovascular diseases. HDL is mainly assembled in the liver through the ATP-binding cassette transporter (ABCA1) pathway. In humans, plasma HDL-cholesterol levels are positively correlated with plasma adiponectin (APN) concentrations. Recently, we reported that APN enhanced apolipoprotein A-I (apoA-I) secretion and ABCA1 expression in HepG2 cells. In the present study, we investigated HDL assembly in APN-knockout (KO) mice. The apoA-I protein levels in plasma and liver were reduced in APN-KO mice compared with wild-type-mice. The ABCA1 expression in liver was also decreased in APN-KO mice. APN deficiency might cause the impaired HDL assembly by decreasing ABCA1 expression and apoA-I synthesis in the liver.

Objective— Obesity is recognized increasingly as a major risk factor for kidney disease. We reported previously that plasma adiponectin levels were decreased in obesity, and that adiponectin had defensive properties against type 2 diabetes and hypertension. In this study, we investigated the role of adiponectin for kidney disease in a subtotal nephrectomized mouse model. Methods and Results— Subtotal (5/6) nephrectomy was performed in adiponectin-knockout (APN-KO) and wild-type (WT) mice. The procedure resulted in significant accumulation of adiponectin in glomeruli and interstitium in the remnant kidney. Urinary albumin excretion, glomerular hypertrophy, and tubulointerstitial fibrosis were significantly worse in APN-KO mice compared with WT mice. Intraglomerular macrophage infiltration and mRNA levels of vascular cell adhesion molecule (VCAM)-1, MCP-1, tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-β1, collagen type I/III, and NADPH oxidase components were significantly increased in KO mice compared with WT mice. Treatment of APN-KO mice with adenovirus-mediated adiponectin resulted in amelioration of albuminuria, glomerular hypertrophy, and tubulointerstitial fibrosis and reduced the elevated levels of VCAM-1, MCP-1, TNF-α, TGF-β1, collagen type I/III, and NADPH oxidase components mRNAs to the same levels as those in WT mice. Conclusions— Adiponectin accumulates to the injured kidney, and prevents glomerular and tubulointerstitial injury through modulating inflammation and oxidative stress.

Adipose tissue, which classically has been considered as an energy-storing organ, is now viewed as a massive source of bioactive substances such as leptin, tumor necrosis factor (TNF)-alpha, and adiponectin. Adiponectin was discovered to be the most abundant adipose-specific transcript. Its function had been unclear, but epidemiological and clinical studies have demonstrated that serum levels of adiponectin are inversely associated with body weight, especially abdominal visceral fat accumulation. In addition, adiponectin was inversely related to cardiovascular risk factors, such as insulin resistance, blood pressure, and low-density lipoprotein (LDL) cholesterol and triglyceride levels, and was positively related to high-density lipoprotein (HDL) cholesterol levels. Moreover, low adiponectin concentration is associated with a high incidence of cardiovascular disease (CVD), diabetes, some kinds of cancer, and other various diseases. These associations suggest the clinical significance of adiponectin, and a number of investigations are now being conducted to clarify the biological functions of adiponectin. Recent studies have revealed that adiponectin exhibits antiinflammatory, antiatherogenic, and antidiabetic properties. In addition, adiponectin has been thought to be a key molecule in "metabolic syndrome," which is an epidemiological target for preventing cardiovascular disease. Various functions of adiponectin may possibly serve to prevent and treat obesity-related diseases and CVD. Furthermore, enhancement of adiponectin secretion or action may become a promising therapeutic target.

Tangier disease (TD) is characterized by a deficiency of high density lipoprotein (HDL) in plasma and patients with TD have an increased risk for coronary artery disease (CAD). Recently, we reported that fibroblasts from TD exhibited large and flattened morphology, which is often observed in senescent cells. On the other hand, data have accumulated to show the relationship between cellular senescence and development of atherosclerotic CAD. The aim of the present study was to investigate whether TD fibroblasts exhibited cellular senescence. The proliferation of TD fibroblasts was gradually decreased at population doubling level (PDL) approximately 10 compared with control cells. TD cells practically ceased proliferation at PDL approximately 30. DNA synthesis was markedly decreased in TD fibroblasts. TD cells exhibited a higher positive rate for senescence-associated beta-galactosidase (SA-beta-gal), which is one of the biomarkers of cellular senescence in vitro. These data showed that TD cells reached cellular senescence at an earlier PDL compared with controls. Although, there was no difference in the telomere length of fibroblasts between TD and controls at the earlier passage (PDL 6), the telomere length of TD cells was shorter than that of controls at the late passage (PDL 25). Taken together, the current study demonstrates that the late-passaged TD fibroblasts showed senescent phenotype in vitro, which might be related to the increased cardiovascular manifestations in TD patients.

While aging is unavoidable, the aging mechanism is still unclear because of its complexity. Smoking causes premature death and is considered as an environmental aging accelerator. In the present study, we focused on the influence of smoking to the serum concentration of anti-aging protein α-klotho (αKl) and the β-klotho-associated protein fibroblast growth factor (FGF)-21 in men. Subjects consisted of apparently healthy men over 40 years of age who underwent health examination. Physical and biochemical parameters, including the levels of several cytokines and growth factors, were obtained from the subjects. Among middle-aged men (46.1 ± 5.1 years), serum levels of FGF-21, soluble αKl (sαKl) and inflammation-related cytokine interleukin (IL)-6 were significantly higher in smokers than in never-smokers. Serum levels of FGF-21 increased and correlated with alanine transaminase, γ guanosine-5′-triphosphate and total cholesterol only in smokers, suggesting FGF-21 as a metabolic disorder-related factor in smokers. In aged men (60.3 ± 1.7 years), although the serum levels of sαKl in never-smokers were low, smokers showed highly increased serum levels of sαKl. Serum levels of sαKl was correlated with IL-6 in middle-aged never-smokers, suggesting sαKl regulates IL-6. However, this correlation was disrupted in smokers and aged men.

We experienced a family with novel massive tendon xanthomatosis which can be excluded from known disease causing xanthomatosis. The proband was a 58-year-old man who had necrosis in his massive Achilles tendon xanthoma. Three of 5 brothers including him and his nephew had the same clinical phenotype. The systemic tendon xanthomatosis became apparent around 30 years of their age. The proband and his elder brother had mild elevations of serum total cholesterol level (251 and 228 mg/dL, respectively). The low-density lipoprotein receptor activity of the proband's lymphocytes was normal. Neither plant sterol nor cholestanol level was increased in the proband's plasma. Magnetic resonance image of the proband's Achilles tendon demonstrated a massive expansion of the soft tissue with salami sausage-like appearance in his heels (50 mm in thickness). The physiological function of macrophages (MPhi) from the patients was investigated to clarify the mechanism for the formation of xanthomatosis. There was no significant difference in the uptake of oxidized low-density lipoprotein between the proband's MPhi and the control. High-density lipoprotein 3-mediated cholesterol efflux from the patients' MPhi (n = 2) was significantly reduced compared with the controls (n = 3), whereas there was no difference in apolipoprotein (apo) A-I-mediated cholesterol efflux between the patients' MPhi and the controls. Furthermore, there was no reduction of the messenger RNA levels of ATP-binding cassette transporter 1 (ABCA1), which is involved in apo A-I-mediated cholesterol efflux, in the proband's MPhi compared with the control. The present study demonstrates that the mechanism for the formation of novel familial massive tendon xanthomatosis may be, at least in part, associated with decreased high-density lipoprotein 3, but not free apo A-I-mediated cholesterol efflux from MPhi in vivo.

Background— Dysregulation of adipocyte-derived bioactive molecules plays an important role in the development of atherosclerosis. We previously reported that adiponectin, an adipocyte-specific plasma protein, accumulated in the injured artery from the plasma and suppressed endothelial inflammatory response and vascular smooth muscle cell proliferation, as well as macrophage-to-foam cell transformation in vitro. The current study investigated whether the increased plasma adiponectin could actually reduce atherosclerosis in vivo. Methods and Results— Apolipoprotein E-deficient mice were treated with recombinant adenovirus expressing human adiponectin (Ad-APN) or β-galactosidase (Ad-βgal). The plasma adiponectin levels in Ad-APN–treated mice increased 48 times as much as those in Ad-βgal treated mice. On the 14th day after injection, the lesion formation in aortic sinus was inhibited in Ad-APN–treated mice by 30% compared with Ad-βgal–treated mice ( P P Conclusions— These findings documented for the first time that elevated plasma adiponectin suppresses the development of atherosclerosis in vivo.

Obesity is more linked to vascular disease, including atherosclerosis and restenotic change, after balloon angioplasty. The precise mechanism linking obesity and vascular disease is still unclear. Previously we have demonstrated that the plasma levels of adiponectin, an adipose-derived hormone, decreases in obese subjects, and that hypoadiponectinemia is associated to ischemic heart disease. In current the study, we investigated the in vivorole of adiponectin on the neointimal thickening after artery injury using adiponectin-deficient mice and adiponectin-producing adenovirus. Adiponectin-deficient mice showed severe neointimal thickening and increased proliferation of vascular smooth muscle cells in mechanically injured arteries. Adenovirus-mediated supplement of adiponectin attenuated neointimal proliferation. In cultured smooth muscle cells, adiponectin attenuated DNA synthesis induced by growth factors including platelet-derived growth factor, heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF), basic fibroblast growth factor, and EGF and cell proliferation and migration induced by HB-EGF. In cultured endothelial cells, adiponectin attenuated HB-EGF expression stimulated by tumor necrosis factor α. The current study suggests an adipo-vascular axis, a direct link between fat and artery. A therapeutic strategy to increase plasma adiponectin should be useful in preventing vascular restenosis after angioplasty.

Background — Vascular smooth muscle cell proliferation plays an important role in the development of atherosclerosis. We previously reported that adiponectin, an adipocyte-specific plasma protein, accumulated in the human injured artery and suppressed endothelial inflammatory response as well as macrophage-to-foam cell transformation. The present study investigated the effects of adiponectin on proliferation and migration of human aortic smooth muscle cells (HASMCs). Methods and Results — HASMC proliferation was estimated by [ 3 H] thymidine uptake and cell number. Cell migration assay was performed using a Boyden chamber. Physiological concentrations of adiponectin significantly suppressed both proliferation and migration of HASMCs stimulated with platelet-derived growth factor (PDGF)-BB. Adiponectin specifically bound to 125 I-PDGF-BB and significantly inhibited the association of 125 I-PDGF-BB with HASMCs, but no effects were observed on the binding of 125 I-PDGF-AA or 125 I-heparin–binding epidermal growth factor (EGF)–like growth factor (HB-EGF) to HASMCs. Adiponectin strongly and dose-dependently suppressed PDGF-BB–induced p42/44 extracellular signal–related kinase (ERK) phosphorylation and PDGF β-receptor autophosphorylation analyzed by immunoblot. Adiponectin also reduced PDGF-AA–stimulated or HB-EGF–stimulated ERK phosphorylation in a dose-dependent manner without affecting autophosphorylation of PDGF α-receptor or EGF receptor. Conclusions — The adipocyte-derived plasma protein adiponectin strongly suppressed HASMC proliferation and migration through direct binding with PDGF-BB and generally inhibited growth factor–stimulated ERK signal in HASMCs, suggesting that adiponectin acts as a modulator for vascular remodeling.

Background: Smoking and metabolic syndrome (MetS) are major public health problems in modern society and are important risk factors of cardiovascular disease (CVD). The association of smoking, MetS, and CVD is widely reported, but reports targeted to women are few. In the present study, we evaluated risk factors, including visceral fat area (VFA), for CVD and development of subclinical atherosclerosis in female smokers especially. Methods and Results: Subjects consisted of 162 apparent healthy female and male smokers, and 315 age-matched never-smokers who underwent a health examination in the Osaka University Health Care Center. For female smokers, lifestyle and carotid intima-media thickness (IMT) were evaluated. Triglycerides were significantly higher and high-density lipoprotein-cholesterol significantly lower in smokers than in never-smokers for both men and women. However, VFA was significantly high only in smoking women when compared with never-smokers. Multivariate analysis revealed that age, body mass index, and smoking were the independent predictors of high VFA in women. In addition, annual IMT increase was significantly higher in smokers than never-smokers in women. Conclusions: VFA was notably high in female smokers, but the difference was not observed in men. Smoking habit is an important risk factor of visceral fat accumulation and progression of subclinical atherosclerosis in women. (Circ J 2014; 78: 1259–1263)

Background —Excessive lipid accumulation in macrophages plays an important role in the development of atherosclerosis. Recently, we discovered an adipocyte-specific plasma protein, adiponectin, that is decreased in patients with coronary artery disease. We previously demonstrated that adiponectin acts as a modulator for proinflammatory stimuli and inhibits monocyte adhesion to endothelial cells. The present study investigated the effects of adiponectin on lipid accumulation in human monocyte-derived macrophages. Methods and Results —Human monocytes were differentiated into macrophages by incubation in human type AB serum for 7 days, and the effects of adiponectin were investigated at different time intervals. Treatment with physiological concentrations of adiponectin reduced intracellular cholesteryl ester content, as determined using the enzymatic, fluorometric method. The adiponectin-treated macrophages contained fewer lipid droplets stained by oil red O. Adiponectin suppressed the expression of the class A macrophage scavenger receptor (MSR) at both mRNA and protein levels by Northern and immunoblot analyses, respectively, without affecting the expression of CD36, which was quantified by flow cytometry. Adiponectin reduced the class A MSR promoter activity, as measured by luciferase reporter assay. Adiponectin treatment dose-dependently decreased class A MSR ligand binding and uptake activities. The mRNA level of lipoprotein lipase as a marker of macrophage differentiation was decreased by adiponectin treatment, but that of apolipoprotein E was not altered. Adiponectin was detected around macrophages in the human injured aorta by immunohistochemistry. Conclusions —The adipocyte-derived plasma protein adiponectin suppressed macrophage-to-foam cell transformation, suggesting that adiponectin may act as a modulator for macrophage-to-foam cell transformation.

Abstract —Adiponectin is a novel, adipose-specific protein abundantly present in the circulation, and it has antiatherogenic properties. We analyzed the plasma adiponectin concentrations in age- and body mass index (BMI)–matched nondiabetic and type 2 diabetic subjects with and without coronary artery disease (CAD). Plasma levels of adiponectin in the diabetic subjects without CAD were lower than those in nondiabetic subjects (6.6±0.4 versus 7.9±0.5 μg/mL in men, 7.6±0.7 versus 11.7±1.0 μg/mL in women; P P r =−0.18, P r =−0.26, P

Abstract —CD36 is one of the major receptors for oxidized low density lipoproteins belonging to macrophage (Mφ) scavenger receptor (SR) class B and is thought to play an important role in the foam cell formation from monocyte-Mφ in the atherosclerotic lesions. Although it has been hypothesized that smooth muscle cells (SMCs) may be the other origin of foam cells in vivo, supporting data are still very limited. In the present study, we have tested the expression of a variety of SRs, including CD36, in 8 lots of primary human aortic SMCs (HASMCs) explanted from 8 different donors. Functional CD36 was expressed in cultured HASMCs, and the levels of expression were widely ranged between the lots. SR class A (SR-A) was expressed abundantly in CD36-negative lots. Other Mφ markers, such as CD32 and CD68, were expressed in all lots tested. These data suggest that the cultured HASMCs gained an Mφ-like phenotype. To determine the mechanism for the above-described phenotypic change, we have tested the expression of a nuclear receptor, peroxisome proliferator activated receptor-γ, in those cells. This nuclear receptor was abundantly expressed in CD36-positive lots, whereas c- fms was expressed abundantly in CD36-negative/SR-A–positive lots. The synthetic ligand of peroxisome proliferator activated receptor-γ, troglitazone, upregulated the expression of CD36 only in CD36-positive lots. These observations demonstrate that cultured HASMCs can gain an Mφ-like phenotype, possibly classified by the expression of CD36 or SR-A. The present study may support the possibilities of transformation of HASMCs into foam cells in vivo.

Adipose tissue secretes a variety of proteins into the bloodstream. We have previously reported a novel cDNA, apM1 (adipose most abundant gene transcript 1), which is specifically and abundantly expressed in adipose tissue [1]. Primary structure analysis predicted that the apM1 gene product possesses significant homology to collagens VIII, X and complement factor C1q, and we named it adiponectin. In the current study, we analyzed characteristics of adiponectin in vitro and in vivo. Adiponectin protein was proved to be secreted into the medium when the cDNA was transfected to COS cells. Anti-adiponectin cross-reactivities were abundantly detected in the human plasma. In solid-phase binding assays, adiponectin specifically bound to collagen types I, III and V, which are present in vascular intima. Immunohistochemical analysis revealed that adiponectin was detected in the walls of the catheter-injured vessels but not in the intact vascular walls. These data suggest that adiponectin is a plasma protein produced by adipose tissue and accumulates in vascular walls when the endothelial barrier is injured.

Abstract —CD36 is a glycoprotein with an M r of 88 kDa that is expressed on platelets, monocytes/macrophages, capillary endothelial cells, and adipocytes. We previously demonstrated that CD36 is involved in the uptake of oxidized low density lipoprotein (OxLDL) by using CD36-deficient macrophages ( J Clin Invest . 1995;96:1859). However, the regulation of CD36 expression in human monocyte–derived macrophages has not been fully elucidated. The current study attempted to clarify the effect of OxLDL and cytokines, both of which are present in atherosclerotic lesions and may play an important role in atherogenesis, on the expression of CD36. A cell enzyme-linked immunosorbent assay and flow cytometry were used to detect CD36 protein. A ribonuclease protection assay was used to measure CD36 mRNA in human monocyte–derived macrophages. The expression of CD36 was increased during the differentiation of monocytes to macrophages. Incubation of macrophages with 25 μg/mL OxLDL for 24 hours increased the level of CD36 protein by 56% and that of CD36 mRNA by 58%. Lysophosphatidylcholine did not affect the expression of CD36. The effects of OxLDL were demonstrated in macrophages that had already differentiated to the point where CD36 expression was almost maximal. Interferon-γ (IFN-γ) reduced the expression of CD36 in a dose-dependent manner. A concentration of 1000 U/mL IFN-γ significantly reduced the expression of CD36 protein by 57% and that of CD36 mRNA by 30%. In conclusion, CD36 may be important in the formation of foam cells by induction through its ligand (OxLDL). Moreover, some local factors, such as IFN-γ, may suppress CD36 expression on macrophages in human atherosclerotic lesions.

Hyper-low-density lipoprotein (LDL)-cholesterolaemia is a potent risk factor for coronary atherosclerosis. We have recently demonstrated that a cluster of risk factors including insulin resistance, glucose intolerance, hypertriglyceridaemia, and hypertension based on intra-abdominal visceral fat accumulation are closely related to coronary artery disease. In the current study, we evaluated the relationship between visceral fat accumulation and the severity and distribution of coronary atherosclerosis in familial hypercholesterolaemia (FH).The effect of visceral fat accumulation on coronary lesions and risk factors in patients with FH was investigated.Thirty-one male patients with heterozygous FH who underwent coronary angiography.Abdominal fat distribution was estimated by a cross-sectional computed tomographic scan at the umbilical level. Plasma lipid, glucose and insulin concentrations and blood pressure were measured. A 75 g oral glucose tolerance test was also performed.The patients were divided into two groups according to the degree of visceral fat accumulation. Fifteen patients had high visceral fat accumulation (High VF group) and 16 patients had normal visceral fat accumulation (Normal VF group). Body mass index (BMI) and subcutaneous fat area were significantly higher in the high VF group. Baseline serum triglyceride was significantly higher and baseline low-density lipoprotein (LDL)-cholesterol and reduction of LDL-cholesterol during treatment were significantly lower in High VF group. Fasting plasma glucose and insulin concentrations, and systolic and diastolic pressures were significantly higher in the High VF group. Significant correlations were found between visceral fat area and the sum of the glucose and insulin concentration during an oral glucose tolerance test. Visceral fat area was significantly correlated with the severity of coronary stenosis index. Distal coronary lesions were significantly more frequent in the High VF group. Moreover, the correlation between the visceral fat area and coronary stenosis index was found to be independent of age, BMI, and subcutaneous fat area by multiple regression analysis.Visceral fat accumulation is a potent cardiovascular risk factor in heterozygous FH.

We examined whether or not alpha 1-adrenergic stimulation increases the tolerance of the heart to ischemia using a hypoxia-reoxygenation model of cardiac myocytes. After exposure to norepinephrine (NE; 0.2 microM) for 24 h, the manganese superoxide dismutase (Mn-SOD) content and activity in the cells were increased from 0.61 +/- 0.03 to 0.87 +/- 0.04 microgram/dish and 22 +/- 1 to 55 +/- 4 U/dish, respectively. The specific activity of Mn-SOD was also increased from 36 to 63 U/microgram Mn-SOD protein after the stimulation with NE. Prazosin (2 microM) abolished the increase in Mn-SOD activity (U/mg total protein). Creatine kinase (CK) release after hypoxia (PO2 7 mmHg; 3 h)-reoxygenation (1 h) from cells pretreated with NE in the presence of propranolol and yohimbine for 24 h was attenuated by 48% compared with that from cells without NE stimulation. When antisense oligodeoxyribonucleotides to Mn-SOD were added to myocyte cultures, the increase in Mn-SOD activity (U/mg total protein) and the attenuation of CK release after the addition of NE in the presence of propranolol and yohimbine were not observed. These results suggest that alpha 1-adrenergic stimulation increases the tolerance of myocytes to hypoxia through induction and activation of Mn-SOD.

Body fat distribution can be assessed by computed tomography (CT). The ratio of umbilicus was used to classify obese subjects as having visceral fat obesity (VFO) or subcutaneous fat obesity (SFO). Serum triglyceride and total cholesterol levels and plasma glucose area in an oral glucose tolerance test were higher in patients with VFO than in those with SFO. Significant positive correlations were demonstrated between V/S ratio and plasma glucose area, serum triglyceride level, and total cholesterol level as well as systolic or diastolic blood pressure. VFO was more frequently associated with coronary artery disease. Moreover, VFO was more often accompanied by multiple risk factors than was SFO. Steady-state plasma glucose (SSPG) level was significantly higher in patients with VFO than with SFO, suggesting that insulin resistance may be more remarkable in VFO than in SFO. Furthermore, visceral fat accumulation was also associated with these complications even in nonobese subjects. Visceral fat area (VFA) was significantly correlated with fasting plasma glucose, serum triglyceride, and total cholesterol levels. Animal models such as Goto-Kakizaki (GK) rats with ventromedial hypothalamus (VMH) lesions and Otsuka-Long-Evans-Tokushima-Fatty (OLETF) rats were accompanied by visceral fat accumulation and an early stage of aortic atherosclerosis. Aging, sex hormone, genetic, and dietary factors and physical inactivity may induce visceral fat accumulation. Visceral fat is characterized by its high lipogenic activity as well as its accelerated lipolytic activity. High levels of portal free fatty acids (FFAs) may eventually result in an enhancement of hepatic triglyceride synthesis, causing hyperlipidemia. High portal FFA levels would also induce insulin resistance, thereby causing glucose intolerance, hypertension, and finally atherosclerosis. We propose a term, "visceral fat syndrome," as a highly atherogenic state, which includes visceral fat accumulation, glucose intolerance (insulin resistance), hyperlipidemia, and hypertension.

It is not known what types of factors may contribute to the development of complications in obese children. In the current investigation, we have performed a cross-sectional and a longitudinal study in Japanese obese children to clarify the relationship of the extent of obesity, fat distribution, insulin resistance, and aging to the development of obesity-related complications. In the cross-sectional study of 329 obese boys and 142 obese girls aged 7 to 15 years, the fasting plasma immunoreactive insulin (IRI) level was significantly higher than that of 46 non-obese boys and 48 non-obese girls (boys, 13.4 +/- 6.7 v 4.9 +/- 1.9 microU/mL, P < .001; girls, 14.0 +/- 5.9 v 4.8 +/- 1.8, P < .001). Linear regression analysis demonstrated that fasting plasma IRI correlated positively with fasting plasma glucose (FPG), triglycerides (TG), uric acid (UA), and systolic blood pressure (SBP) in obese boys, and with TG, SBP, and diastolic blood pressure (DBP) in obese girls, and negatively with serum high-density lipoprotein cholesterol (HDL-C) in both obese boys and girls. Multiple regression analysis demonstrated that fasting plasma IRI was independently and positively correlated with FPG, TG, and SBP in obese boys. Fasting plasma IRI in obese girls was positively correlated with TG, SBP, and DBP, and negatively with HDL-C. FPG decreased significantly in non-obese children at the onset of puberty, but it remained unchanged in obese children. Fasting plasma IRI and the IRI to glucose ratio increased with age in obese children, whereas they did not show any significant changes in non-obese children.(ABSTRACT TRUNCATED AT 250 WORDS)

Aim High density lipoprotein (HDL) has multi-antiatherogenic effects such as antioxidation and anti-inflammation, in addition to being a key mediator of reverse cholesterol transport. Probucol, known as a lipid lowering drug, is also a potent antioxidant, but it decreases serum HDL cholesterol (HDL-C) levels. To elucidate the effect of probucol on antioxidant properties of HDL, we investigated the function of HDL derived from patients with heterozygous familial hypercholesterolemia (FH) who have been treated with probucol. Methods and results Probucol-treated FH patients (n=21) showed a 47% reduction of serum HDL-C levels compared to probucol-untreated FH patients (n=15). High performance liquid chromatography (HPLC) analysis revealed that probucol diminished HDL particle size compared to the non-treated group. Antioxidant capacity of HDL was evaluated by its effect to protect reference LDL from oxidation induced in the presence of an oxidizing agent, AAPH. The HDL derived from the probucol-treated group demonstrated a significantly prolonged time to start oxidation by 112%, decreased the maximum oxidation rate by 14%, and lowered the maximum concentration of conjugated dienes formation by 15%. Furthermore, HDL-associated paraoxonase 1 (PON1) activity, but not platelet-activating factor acetyl-hydrolase (PAF-AH) correlated with these measurements of HDL anti-oxidative activity. Treatment with probucol in vitro and inhibition of PON1 activity demonstrated that probucol in HDL particles and increase of PON1 activity might largely contribute to the increase of HDL anti-oxidative activity. Conclusion Probucol reduced HDL-C levels and HDL particle size in patients with heterozygous FH, while it concomitantly enhanced HDL anti-oxidative properties, possibly through increasing PON1 activity.

Objective Adiponectin (APN) improves insulin resistance and prevents atherosclerosis, and HDL removes cholesterol from atherosclerotic lesions. We have demonstrated that serum HDL-cholesterol (HDL-C) and APN concentrations are positively correlated and that APN accelerates reverse cholesterol transport (RCT) by increasing HDL synthesis in the liver and cholesterol efflux from macrophages. We previously reported that APN reduced apolipoprotein (apo) B secretion from the liver. It is well-known that insulin resistance influences the lipoprotein profile. In this study, we investigated the clinical significance of APN levels and insulin resistance in lipoprotein metabolism. Material/method We investigated the correlation between serum APN concentration, HOMA-R, the lipid concentrations and lipoprotein particle size by high-performance liquid chromatography (HPLC) in 245 Japanese men during an annual health checkup. Results Serum APN level was positively correlated with the cholesterol content in large LDL and HDL particles, but inversely correlated with the cholesterol content in large VLDL and small LDL particles. HOMA-R was negatively correlated with the cholesterol content in large LDL and HDL particles and positively correlated with the cholesterol content in large VLDL and small LDL particles. By multivariate analysis, APN was correlated with the particle size of LDL-C and HDL-C independently of age, BMI and HOMA-R. Conclusions APN may be associated with the formation of both HDL and LDL particles, reflecting the enhancement of RCT and the improvement in TG-rich lipoprotein metabolism and insulin resistance.

Associations between intra-abdominal visceral fat accumulations and coronary risk factors were studied in a sample of 29 non-obese men aged 57 ± 10 years with coronary artery disease (CAD). Their body mass indexes (BMI) were 23.8 ± 1.5 (range 18.7–26.3). The visceral fat area (VFA) and the subcutaneous fat area (SFA) were measured at the level of the umbilicus by computed tomography. In patients with CAD, the average VFA was significantly increased compared with that in 54 control subjects without CAD, matched for sex, age, and BMI (117.2 ± 53.1 vs. 93.8 ± 38.6 cm2, P < 0.05). However, their average SFA was not statistically different (111.2 ± 33.3 vs. 106.3 ± 35.7 cm2, N.S.). Eleven CAD patients (38%) and nine control subjects (17%) had greater than 2S. D. higher than the mean VFA obtained from 22 healthy subjects extracted from the control subjects. Accordingly, the proportion of the subjects with high VFA was significantly higher in the CAD group. This group also had significantly higher levels of plasma glucose and insulin areas than controls determined by oral glucose tolerance tests. This may be due to insulin resistance. The proportion of the subjects with multiple risk factors including hyperlipidemia, hyperglycemia, and hypertension was significantly higher in the CAD patients with high VFA compared with the control subjects with normal VFA (CAD with high VFA 82% and control with normal VFA 33%). These findings suggest that visceral fat accumulations may play an important role in the occurrence of CAD regardless of obesity. Accordingly, we propose the term ‘visceral fat syndrome’, which encompasses visceral fat accumulation, glucose intolerance, hyperlipidemia, and hypertension. Patients with this syndrome have increased susceptibility to coronary sclerosis from these risk factors based on visceral fat accumulation.

Aim: Postprandial hyperlipidemia (PH) is thought to be caused by the impaired postprandial metabolism of triglycerides (TG)-rich lipoproteins in both endogenous and exogenous pathways; however, there is no consensus. It is difficult to estimate the presence of PH without performing a time-consuming oral fat loading (OFL) test, so postprandial lipoprotein metabolism was analyzed by measuring the postprandial levels of apolipoprotein (apo) B-48 and apo B-100, and the correlation between postprandial TG increase and fasting apoB-48 levels was assessed to establish a good marker of PH without performing an OFL test.Methods: Ten male normolipidemic subjects were loaded with a high-fat (HF, 1045 kcal) or standard (ST, 566 kcal) meal, and the lipids, apolipoproteins and lipoprotein profiles were analyzed after each meal.Results: TG, apo B-48, remnant-like particles (RLP)-cholesterol and RLP-TG levels were increased and their levels were significantly higher after intake of the HF meal than the ST meal; however, there was no postprandial increase in apo B-100 and LDL-C levels. Postprandial increases in TG levels of CM, VLDL, LDL and HDL were significantly higher after intake of the HF meal than the ST meal. Fasting apo B-48 levels were strongly correlated with the incremental area under the curve of TG after intake of the HF meal, but not the ST meal.Conclusion: Postprandial TG increase was mainly due to increased CM and CM-R, but not VLDL. Measurement of fasting serum apo B-48 may be a simple and useful method for assessment of the existence of PH.

Background Apolipoprotein B-48 (apoB-48) is a constituent of chylomicron remnants synthesized in the small intestines. The serum concentration of apoB-48 at fasting has been reported to be a marker of postprandial hyperlipidemia, a presumed risk factor for atherosclerosis. Methods We evaluated the basal performance of a recently developed chemiluminescent enzyme immunoassay (CLEIA). We also examined the correlations between serum apoB-48 concentrations and other lipid concentrations or life style patterns, including smoking and drinking. We analyzed the data of 273 clinical samples by multiple regression analysis to examine the influence of other serum lipid values, age, sex, smoking, drinking status and BMI on serum apoB-48 values. Results Within-run and between-run precision was obtained with 1.7–2.7% and 1.2–7.3%, respectively. The correlativity of enzyme-linked immunosorbent assay was correlation coefficient r = 0.953, and regression y = 1.02 × −1.59. Serum apoB-48 concentrations were higher in males than in females, and were correlated with the status of smoking as well as with remnant-like particle-cholesterol (RLP-C) concentrations. Patients with the metabolic syndrome showed higher values of serum apoB-48 compared with control subjects. Conclusion Serum apoB-48 measurement by CLEIA was satisfactory for clinical use to assess abnormalities in the chylomicron remnant metabolism.

Sitosterolemia is a rare, autosomal recessive inherited sterol storage disease associated with high tissue and serum plant sterol concentrations, caused by mutations in the adenosine triphosphate-bind-ing cassette (ABC) transporter ABCG5 or ABCG8 genes. Markedly increased serum concentration of plant sterols. such as sitosterol and campesterol, cause premature atherosclerosis and massive xanthomas. Hitherto known treatments for sitosterolemia, including a low-sterol diet, bile-salt binding resins, ileal bypass surgery and low density lipoprotein (LDL) apheresis have not yielded sufficient reduction of serum plant sterol levels and many patients show a sustained elevation of plant sterol levels, subsequently developing premature atherosclerotic cardiovascular diseases. Ezetimibe, an inhibitor of intestinal cholesterol absorption through its binding to Niemann-Pick C1-like 1 (NPC1L1), has been widely used for decreasing serum LDL-cholesterol levels in patients with hypercholesterolemia. Ezetimibe also reduces the gastrointestinal absorption of plant sterols, thereby also lowering the serum concentrations of plant sterols. This pharmacological property of ezetimibe shows its potential as a novel effective therapy for sitosterolemia. In the current review, we discuss the current therapy for patients with sitosterolemia and present two Japanese adolescent patients with this disease, one of whom underwent percutaneous coronary intervention for accelerated coronary atherosclerosis. Ezetimibe administration in addition to conventional drug therapy successfully reduced serum sitosterol levels by 51.3% and 48.9%, respectively, in the two patients, demonstrating ezetimibe as a novel and potent treatment agent for sitosterolemia that could work additively with conventional drug therapy.

Numerous large-scale clinical studies have revealed that the low-density lipoprotein cholesterol (LDL-C)-lowering effect of 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitors (statins) prevents coronary heart disease (CHD). Statins have not only LDL-C-lowering effects but also high-density lipoprotein cholesterol (HDL-C)-elevating effects, which differ among statins. In this article, we discuss the molecular mechanisms of HDL-C elevation by statins and its effect on HDL functions. We summarize the reports to date on the effects of statins on various proteins, enzymes and receptors involved in reverse cholesterol transport (RCT), which is one of the protective systems against atherosclerosis. Since statins increase the synthesis of apolipoprotein A-I (ApoA-I) and HDL neogenesis in the liver, the HDL-C-increasing effect of statins may reflect RCT activation. Moreover, HDL has pleiotropic effects, including anti-inflammatory and anti-oxidative effects, as well as RCT. In the future, it may be necessary to assess the functions of HDL elevated by statins, and select statins based on differences in their effects in clinical practice.