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Primary hyperchylomicronemia is characterized by marked hypertriglyceridemia exceeding 1,000 mg/dL. It is caused by dysfunctional mutations in specific genes, namely those for lipoprotein lipase (LPL), glycosylphosphatidylinositol-anchored high-density lipoprotein binding protein 1 (GPIHBP1), apolipoprotein C2 (ApoC-II), lipase maturation factor 1 (LMF1), or apolipoprotein A5 (ApoA-V). Importantly, antibodies against LPL or GPIHBP1 have also been reported to induce autoimmune hyperchylomicronemia.The patient was a 46-year-old man diagnosed with immune thrombocytopenia (ITP) at 41 years. At the time, he was administered prednisolone (PSL) and eltrombopag, a thrombopoietin receptor agonist. At 44 years, he suffered from acute myocardial infarction, and PSL was discontinued to avoid enhancing atherogenic risks. He was maintained on eltrombopag monotherapy. After discontinuing PSL, marked hypertriglyceridemia (＞3,000 mg/dL) was observed, which did not improve even after a few years of pemafibrate therapy. Upon referral to our clinic, the triglyceride (TG) level was 2,251 mg/dL, ApoC-II was 19.8 mg/dL, LPL was 11.1 ng/mL (0.02-1.5 ng/mL), GPIHBP1 was 47.7 pg/mL (740.0-1,014.0 pg/mL), and anti-GPIHBP1 antibody was detected. The patient was diagnosed to have anti-GPIHBP1 antibody-positive autoimmune hyperchylomicronemia. He was administered PSL 15 mg/day, and TG levels were controlled at approximately 200 mg/dL.Recent studies have reported that patients with anti-GPIHBP1 antibody-induced autoimmune hyperchylomicronemia had concomitant rheumatoid arthritis, systemic lupus erythematosus, Sjogren's syndrome, Hashimoto's disease, and Graves' disease. We report a rare case of anti-GPIHBP1 antibody-positive autoimmune hyperchylomicronemia with concomitant ITP, which became apparent when PSL was discontinued due to the onset of steroid-induced acute myocardial infarction.

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.

Background and Aim: Immune response including T cell activation after myocardial infarction (MI) is important mechanism in cardiac remodeling. We established a new model of ischemic cardiomyopathy using SR-BI KO/ApoeR61 h/h (SRBI KO) mice in which MI is induced by high fat diet (HFD) for 7 days. We aimed to clarify the precise mechanism leading to post-MI cardiac remodeling: activation of inflammatory CD4 + T-cell subsets and conventional dendritic cells (cDCs), using our non-surgical MI, coronary ligation MI and conditional cCDs KO mice model. Methods and Results: Probucol, a potent antioxidant, was known to improve cardiac remodeling in rat MI model. Using SRBI +/- mice as a non-MI control group, we fed SRBI KO mice HFD to induce MI (non-treatment group) and added probucol (treatment group). With probucol treatment, survival rate and EF were improved, and fibrosis area was reduced. We analyze CD4 + cell subsets in the heart, blood and spleen. Th1 was predominantly increased and activated in border and infarcted area, and decreased with probucol treatment. RNA-seq revealed, specifically Th1 related chemokines, CXCR3 was down-regulated with probucol treatment. Flow data revealed, CXCR3 was highly expressed in Th1 (up to 50%) and decreased with probucol treatment. To elucidate the mechanism of the predominant activation of Th1 after MI, we analyze the dynamics of cDCs. XCR1 + cDCs was activated and decreased with probucol treatment. Furthermore, CXCR3 ligands, CXCL9 and CXCL10, were highly expressed in XCR1 + cDCs (up to 50%). In bone marrow, siglec-H – Ly6C – pre-DCs (XCR1 + cDCs lineage) were increased in non-treatment group and also in coronary ligation MI model, and decreased with probucol treatment. Finally, to confirm the induction of post-MI Th1 type inflammation by XCR1 cDCs, we conducted the conditional depletion of XCR1 + cDCs. In XCR1 KO mice, infiltration of CXCR3 + Th1 in the infarcted area and fibrosis area was decreased, and deterioration of EF, which was evaluated by cardiac MRI, was suppressed after MI. Conclusions: The predominant activation of Th1 after MI exacerbated cardiac remodeling. CXCR3 chemokine system were characteristic of Th1 and XCR1 + cDCs. The modulation of Th1- XCR1 + cDCs interaction could be a novel therapeutic target in post-MI remodeling.

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.

We report a case of Tangier disease with Leriche syndrome and bleeding tendency. In this male patient, nasal hemorrhage had been observed frequently throughout childhood. At 46 years old, he experienced effort angina, and coronary angiography demonstrated 75% stenosis in the right coronary artery. Orange-colored tonsils, mild hepatosplenomegaly and very low levels of serum high-density lipoprotein cholesterol (HDL-C) were observed, and the patient was diagnosed with Tangier disease. At 52 years old, effort angina recurred. Coronary angiography revealed 75% stenosis of the left main trunk, left anterior descending, and right coronary arteries. Stenosis of the brachiocephalic and right common iliac arteries was also recorded. Stents were implanted, and coronary artery bypass surgery was performed. At 53 years old, 15 months after surgery, the patient reported intermittent claudication, coldness of feet, and impotence. Aortic angiography showed progression of the stenosis at the bifurcation of the common iliac artery. The patient was diagnosed with Leriche syndrome, and aorta-left external iliac artery graft bypass surgery was performed. After surgery, oozing from subcutaneous tissue and leaking from the anastomotic region were observed. Additional analysis revealed two single-nucleotide polymorphisms (V825I and N935T) in the ATP-binding cassette transporter A1 (ABCA1) gene, and accumulation of small dense low-density lipoprotein together with low levels of HDL-C. In Tangier disease, HDL-C is markedly decreased because of ABCA1 deficiency. However, this is the first reported case to exhibit extensive atherosclerosis and bleeding tendency. This patient had atypical extensive and multiple atherosclerotic lesions, accompanied by Leriche syndrome and uncontrollable bleeding.

Background: Familial hypercholesterolemia (FH) is at high risk of premature coronary artery disease (CAD). Japan Atherosclerosis Society (JAS) has published original criteria for FH. Patients are diagnosed clinical FH if at least 2 of the following criteria are satisfied: i) LDL-C ≥ 180 mg/dL, ii) Tendon/ skin xanthomas, iii) History of FH or premature CAD within 2nd degree blood relatives. Although it is easy to apply these criteria for FH-suspected patients, in fact, we are not sure whether other lipid-related genes may be overlapped in addition to those of conventional FH genes such as LDL receptor (LDLR), apolipoprotein B (APOB), and proprotein convertase subtilisin/kexin type 9 (PCSK9). Methods and Results: Ninety-one heterozygous FH (HeFH) patients in Osaka University Hospital, who met the clinical FH criteria of JAS were enrolled after obtaining informed consent. Genomic DNA for each patient was extracted from peripheral blood cells. Targeted exon sequencing was performed to investigate 36 lipid-related genes including conventional FH genes. We have defined pathogenic variants if they fulfilled i) rare protein truncating variants, ii) rare damaging missense variants, and iii) ClinVar-registered pathogenic or likely pathogenic variants. Among 91 HeFH patients (52.9 ± 14.7 years), 41 patients (45.1%) were males. We have identified LDLR pathogenic variants in 61 patients (67.0%) and PCSK9 variants in 1 patient (1.1%). Among these 62 patients, 22 patients (35.5%) additionally have pathogenic variants of other lipid-related genes, which include apolipoprotein E2 (APOE2) in 1 patient, apolipoprotein E4 (APOE4) in 10 patients, ATP-binding cassette subfamily G member 5 (ABCG5) in 2 patients, apolipoprotein C3 (APOC3) in 1 patient, and CD36 in 10 patients. As for remaining 29 patients without conventional FH gene variants, 13 patients (44.8%) have pathogenic variants of other lipid-related genes, which include APOE4 in 11 patients, apolipoprotein E5 (APOE5) in 1 patient, and variants of ABCG5 in 1 patient. Conclusion: We have identified several variants of lipid-related genes in addition to conventional FH genes in HeFH patients diagnosed according to JAS criteria. These variants may affect the atherogenicity of patients and selection of medication.

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.

Alcohol consumption is one of the major modifiable risk factors of hypertension. The aim of the present retrospective study was to assess the clinical impact of obesity on the association between alcohol consumption and the incidence of hypertension. The present study included 5116 male and 6077 female university employees with a median age of 32 (interquartile range 27–39) who underwent annual health checkups between January 2005 and March 2013. Self-reported drinking frequency was recorded at their first checkup and categorized into rarely and 1–3, 4–6, and 7 days/week. During the median observational period of 4.9 years (interquartile range 2.1–8.3), hypertension, defined as systolic/diastolic blood pressure of ≥140/90 mmHg and/or self-reported treatment for hypertension, was observed in 1067 (20.9%) men and 384 (6.3%) women. Poisson regression models adjusted for clinically relevant factors revealed a dose-dependent association between drinking frequency and the incidence of hypertension in men (adjusted incidence rate ratio [95% confidence interval] of men who drank rarely, 1–3, 4–6, and 7 days/week was 1.00 [reference], 1.12 [0.97–1.30], 1.42 [1.19–1.70], and 1.35 [1.14–1.59], respectively; Ptrend

Aim: A direct oral anti-coagulant, FXa inhibitor, has been applied to the clinical treatment of myocardial infarction (MI). Experimental studies in mice indicated that FXa inhibitors reduced atherosclerosis and prevented cardiac dysfunction after coronary ligation. These studies suggested that protease-activated receptor (PAR) 2, a major receptor of activated FX, may play an important role in atherosclerosis and cardiac remodeling. Methods: The effects of a FXa inhibitor, rivaroxaban, were investigated in a new murine model of ischemic cardiomyopathy (ICM) using SR-BI KO/ApoeR61h/h mice (Hypo E mice) that developed MI by high-fat diet loading. Results: Hypo E mice were fed rivaroxaban-containing (n = 49) or control chow diets (n = 126) after the induction of MI. The survival curve of the rivaroxaban-treated group 2 weeks after the induction of MI was improved significantly as compared with the non-treatment group (survival rate: 75.5% vs. 47.4%, respectively, p = 0.0012). Echocardiography and the expression of BNP showed that rivaroxaban attenuated heart failure. Histological analyses revealed that rivaroxaban reduced aortic atherosclerosis and coronary occlusion, and markedly attenuated cardiac fibrosis. Rivaroxaban treatment decreased cardiac PAR2 levels and pro-inflammatory genes. In vitro, rivaroxaban application demonstrated the increase of cell viability against hypoxia in cardiac myocytes and the reduction of hypoxia-induced inflammation and fibrosis-related molecules in cardiac fibroblasts. The effects of the PAR2 antagonist against hypoxia-induced inflammation were comparable to rivaroxaban in cardiac fibroblasts. Conclusions: Rivaroxaban treatment just after MI in Hypo E mice prevented the progression of ICM by attenuating cardiac remodeling, partially through the suppression of the PAR2-mediated inflammatory pathway.

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).

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.

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.

Familial hypercholesterolemia (FH) patients are characterized by high LDL cholesterol levels in the blood and premature cardiovascular disease. Although most of heterozygous FH patients are able to be treated with statin, ezetimibe and bile acid sequestrants and anti-PCSK9 antibodies, homozygous FH patients are resistant to drug therapy. Therefore, many of homozygous FH patients used to be treated by LDL-apheresis. However, the effect of removing LDL cholesterol is still not sufficient and definitive therapies need to be developed. With the increase of the evidence about the safety of mesenchymal stem cells and percutaneous transhepatic portal approach in islet transplantation, we have developed a cell transplantation therapy with allogeneic adipose tissue-derived multilineage progenitor cells, as an alternative treatment instead of liver transplantation. We have generated a protocol for the phase 1 clinical study. The primary endpoint should be safety evaluation including allergic reaction, rejection reaction, thrombosis and complications in the blood vessel by cell-transplantation. The secondary endpoint should be the efficacy including changes in serum lipid such as LDL-C, TC, HDL-C, TG and Lp(a), and Secession possibility of LDL-apheresis. We transplanted the first case in February, 2016. Then we are collecting clinical data. We would demonstrate the current status and the issues to be solved for the following study.

Introduction: Recent studies have suggested that HDL efflux capacity could be a potentially beneficial assay to predict the risk of cardiovascular diseases (CVDs), compared to HDL cholesterol (HDL-C) levels. Recently, we developed a novel methodology using high-performance gel permeation chromatography (HPLC) to evaluate lipoprotein particle number of each subclass. In this study, we investigated CETP-deficient (CETP-D) patients, who are elevated in HDL-C levels, but not likely to be protected from atherosclerosis as we reported previously. Hypothesis: To evaluate lipoprotein particle number of each subclass may be also useful to predict the risk of CVDs. Methods: Nine CETP-D patients, whose serum CETP mass was less than 0.1μg/mL, were compared with 9 normolipidemic controls. Free cholesterol, cholesteryl ester, triglyceride and phospholipid levels in each 20 lipoprotein subclass were determined by computer-assisted HPLC. Furthermore, we calculated the particle number of each subclass by using HPLC data and serum apolipoprotein levels, which is newly-developed LipoSEARCH® system (Skylight Biotech Inc, Akita). Results: As we reported previously, serum HDL-C levels were markedly elevated in CETP-D patients compared with controls. The number of very large and large HDL particles in CETP-D patients was markedly higher than that in controls (4237.3±2353.4nM vs 213.4±55.7nM, 7672.2±1368.3nM vs 1720.2±536.6nM, respectively; p Conclusions: We have investigated particle numbers of each lipoprotein subclass in CETP-D patients. Our data might indicate that CETP deficiency leads to pro-atherogenic lipoprotein profile.

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

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)

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.

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.

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)

Betacellulin (BTC), a new member of the EGF family, has been reported to be a potent mitogen for rat vascular smooth muscle cells (SMCs). BTC mRNA is known to be expressed in several human organs. However, the localization of BTC in human vascular tissues has not yet been clarified. We investigated whether or not BTC protein is involved in the pathogenesis of human atherosclerosis. Recombinant human BTC showed a mitogenic activity on cultured human aortic SMCs by measuring [3H]thymidine incorporation. The immunohistochemical localization of BTC, SMCs, macrophages, EGF receptors and ErbB4 was examined in autopsied human aortas. BTC was detected in both intimal and medial SMCs of the aortic wall. The percentage of BTC-positive medial SMCs in early types of atherosclerotic lesions decreased with age, but in adult, it was significantly higher in advanced types than in early types of atherosclerotic lesions. BTC-positive SMCs were predominantly localized in the medial side of the intima. Furthermore, numerous BTC-positive SMCs and macrophages were observed around the core lesion of atherosclerotic plaques. Receptors for BTC, EGF receptor and ErbB4, were expressed on SMCs, suggesting that BTC is associated with EGF receptor family-mediated signaling. BTC is produced in human aortic tissue and might play important roles in atherogenesis.

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 —Heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF), a member of the EGF family, has a potent mitogenic activity for vascular smooth muscle cells (SMCs). We previously reported that HB-EGF is involved in atherogenesis of human aorta and coronary arteries. ProHB-EGF (the membrane-anchored form of HB-EGF) has also been demonstrated to possess a mitogenic activity, which is ≈30-fold increased when coexpressed with CD9 in mouse L cells. Thus, in the process of atherogenesis, CD9 may be involved in the proliferation of SMCs. We immunohistochemically investigated the localization of CD9 and proHB-EGF in the human aorta and coronary arteries. In normal aorta and coronary arteries, CD9 immunostaining was virtually negative, whereas proHB-EGF immunostaining was positive, especially in the arteries of babies. In contrast, in atherosclerotic lesions, some intimal SMCs were strongly positive for CD9 and proHB-EGF immunostaining. The juxtacrine growth activities of human aortic SMCs were inhibited in vitro by adding neutralization antibodies for CD9 or adding the specific inhibitor of HB-EGF. Besides, coexpressed CD9 and proHB-EGF cells markedly incorporated [ 3 H]thymidine into the SMCs. CD9 is localized immunohistochemically in the SMCs of the atherosclerotic aorta and coronary arteries. CD9, when coexpressed with proHB-EGF, enhances proHB-EGF activities for SMC growth in a so-called juxtacrine manner in vitro and may be involved in atherogenesis.

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.

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.

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.

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.

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.

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.

Aim: Metabolic syndrome (MetS) and postprandial hypertriglyceridemia (PHTG) are closely related and both are associated with coronary heart disease. We have demonstrated that CD36 deficiency is prevalent in the genetic background of MetS and is accompanied by PHTG concomitantly with an increase in remnants and a decrease in high density lipoprotein cholesterol. These findings make CD36 knockout mice (CD36KO) an interesting model for evaluating PHTG in MetS. Fenofibrate was reported to reduce fasting and postprandial triglyceride (TG) levels in hypertriglyceridemic subjects with MetS. To define its mechanism, we investigated the effect of fenofibrate on PHTG in CD36KO.Methods: Wild-type (WT) and CD36KO mice were fed chow diet and fenofibrate for two weeks. TG concentrations and lipoprotein profiles were assessed during fasting and in the postprandial state in plasma; intestinal mucosa and lymph were collected after oral fat loading for both treatment groups.Results: Fenofibrate treatment markedly suppressed the postprandial TG response in CD36KO along with decreased apoB-48 levels in plasma. HPLC analysis depicted the decrease of TG content in chylomicrons (CM) and CM remnant-sized lipoproteins contributed to this suppression, suggesting that CM and CM remnant production in the intestines might be attenuated by fenofibrate. ApoB-48 and TG levels in intestinal lymph were markedly reduced after treatment. Intestinal mRNA expression of apoB was also reduced in the postprandial state after fenofibrate administration without affecting any other genes related to CM assembly and production.Conclusion: Fenofibrate reduces PHTG in CD36KO partially through attenuating intestinal CM production.

A 48-year-old man was first referred to our clinic in January 1989 because of marked hypocholesterolemia with very low HDL cholesterol, anemia, and hyperbilirubinemia. He had large tonsils, corneal opacities, hepatosplenomegaly, and thrombocytopenia. Serum levels of total cholesterol, triglycerides, and HDL cholesterol were 0.72, 2.6, and 0.16 mmol/L (28, 232, and 6 mg/dL), respectively. Concentrations of apolipoproteins (apo) A-I and A-II were 1.3 and 0.9 μmol/L (3.9 and 1.5 mg/dL), respectively. His daughter’s serum levels of total cholesterol, HDL cholesterol, and apo A-I were 3.3 mmol/L, 0.64 mmol/L, and 34.7 μmol/L (128, 24, and 104 mg/dL), respectively. He was diagnosed with Tangier disease by clinical manifestations, analysis of lipoproteins, and 2D electrophoresis, which confirmed the increase of preproapo A-I. Interestingly, xanthoma in the Achilles’ tendons, which had rarely been reported in patients with Tangier disease, was observed in the patient, and the thickness was 9 mm (mean of bilateral determinations; control, 6±2 mm). Subsequently, …

Aim: Tangier disease (TD), caused by deficiency of ATP-binding cassette transporter A1, is characterized by the absence of high density lipoprotein and the accumulation of cholesteryl esters in many tissues. Recently, it has been reported that ABCA1 is expressed in pancreatic β cells and mice with specific inactivation of ABCA1 in β cells showed markedly impaired insulin secretion, suggesting that ABCA1 deficiency may be involved in diabetes. The aim of the current study was to confirm these findings by the oral glucose tolerance test (OGTT) in human subjects with ABCA1 deficiency.Methods and Results: Four Japanese patients with TD were investigated by OGTT with 75 g glucose. In all TD patients, the plasma glucose concentration after 30 min progressively increased, indicating a type 2 diabetic pattern; however the plasma insulin concentration did not respond well to glucose increase. The calculated insulinogenic index was significantly lower in TD patients than in non-diabetic controls (0.055±0.034 vs 0.775±0.538, mean±SD, p

To define the relation between oxygen-derived free radical (oxy-radical) generation in the reperfused ischemic myocardium and the progression of myocardial damage, we measured oxy-radical generation in the ischemic myocardium and the propagating infarct size in a model of canine coronary occlusion (90 minutes) and reperfusion. We used electron paramagnetic resonance spin-trapping techniques (5,5-dimethyl-1-pyrroline N-oxide [DMPO]) to detect oxy-radicals in the rapidly frozen myocardial samples taken by needle biopsy. There was no detectable generation of DMPO adducts in the normal myocardium before or after reperfusion. In the reperfused ischemic myocardium, electron paramagnetic resonance signals of DMPO-OOH (superoxide anion) and DMPO-OH (hydroxyl radical) were detected, with peak concentrations at 1 hour after reperfusion for DMPO-OOH and at 3 hours after reperfusion for DMPO-OH, respectively. These DMPO adducts were also detected during the early phase (15 seconds) of reperfusion, but the concentrations of these signals were much less than those during the late phase of reperfusion. Treatment with human recombinant superoxide dismutase (2.5 mg/kg/hr) and catalase (2.5 mg/kg/hr) during the course of experiments abolished DMPO-OOH formation but had little effect on DMPO-OH formation. Infarct size (percent of risk area infarcted), quantified by a dual staining method with Evans blue dye and triphenyltetrazolium chloride, was 18.3 +/- 4.8% (mean +/- SEM) at 90 minutes of occlusion. After 5 hours of reperfusion, infarct size increased to 43.6 +/- 7.2%. These results indicate that a greater magnitude of oxy-radical generation was sustained in the ischemic myocardial tissue during the late phase (1-3 hours) of reperfusion, associated with the progression of myocardial infarction. The concurrent appearance of oxy-radicals and progressive infarction may support the view that a chain reaction of oxy-radicals contributes to the propagation of myocardial cell damage in the postischemic heart.