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AIM: Postprandial hypertriglyceridemia (PHTG) is an independent risk factor for coronary heart diseases. PHTG exhibits accumulation of apoB-48 containing chylomicron remnants (CM-Rs) and apoB-100 containing VLDL remnants (VLDL-Rs), which are both known to be atherogenic. However, unlike VLDL-Rs, structural and functional characterization of CM-Rs remains to be elucidated due to challenges in separating CM-Rs from VLDL-Rs. Recently, we successfully isolated CM-Rs and VLDL-Rs utilizing anti-apoB-48 or apoB-100 specific antibodies. This study aimed to characterize the proteome of CM-Rs along with that of VLDL-Rs. METHODS: Eight healthy subjects were enrolled. Venous blood was drawn 3 hours after high-fat-containing meals. We isolated CM-Rs and VLDL-Rs from sera through combination of ultracentrifugation and immunoprecipitation using apoB-48 or apoB-100 specific antibodies, followed by shotgun proteomic analysis. RESULTS: We identified 42 CM-Rs or VLDL-Rs-associated proteins, including 11 potential newly identified proteins such as platelet basic protein (PPBP) and platelet factor 4, which are chemokines secreted from platelets. ApoA-I, apoA-IV, and clusterin, which are also known as HDL-associated proteins, were significantly more abundant in CM-Rs. Interestingly, apoC-I, which reduces the activity of lipoprotein lipase and eventually inhibits catabolism of remnant proteins, was also more abundant in CM-Rs. Moreover, we identified proteins involved in complement regulation such as complement C3 and vitronectin, and those involved in acute-phase response such as PPBP, serum amyloid A protein 2, and protein S100-A8, in both CM-Rs and VLDL-Rs. CONCLUSIONS: We have firstly characterized the proteome of CM-Rs. These findings may provide an explanation for the atherogenic properties of CM-Rs.
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AIM: A twin study is a valuable tool for elucidating the acquired factors against lifestyle diseases such as dyslipidemia, diabetes mellitus, and obesity. We aimed 1. to investigate the factors that affect low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) in monozygotic (MZ) twins, and 2. to identify genes which expression levels changed in pairs with large differences in LDL-C or HDL-C levels. METHODS: The registered database at the Center for Twin Research, Osaka University, containing 263 pairs of MZ twins, was analyzed. 1. The effects of smoking, exercise, nutritional factors, and anthropometric and biochemical parameters on LDL-C or HDL-C levels were examined in MZ twins. 2. RNA sequencing in the peripheral blood mononuclear cells of 59 pairs was analyzed for large differences of LDL-C or HDL-C groups. RESULTS: 1. The ΔLDL-C levels were significantly associated with an older age, the ΔTG levels, and ΔBMI. ΔHDL-C levels were associated with the ΔBMI, ΔTG, ΔTP, and ΔLDL-C levels. The HDL-C levels were affected by smoking and exercise habits. The intakes of cholesterol and saturated fatty acids were not associated with the LDL-C or HDL-C levels. 2. An RNA sequencing analysis revealed that the expression of genes related to the TLR4 and IFNG pathways was suppressed in accordance with the HDL-C levels in the larger ΔHDL-C group among the 59 pairs. CONCLUSION: We identified the factors affecting the LDL-C or HDL-C levels in monozygotic twins. In addition, some types of inflammatory gene expression in peripheral blood mononuclear cells were suppressed in accordance with the HDL-C levels, thus suggesting the importance of weight management and exercise habits in addition to dietary instructions to control the LDL-C or HDL-C levels.
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Cardiac remodeling has no established therapies targeting inflammation. CD4+ T-cell subsets have been reported to play significant roles in healing process after ischemic myocardial injury, but their detailed mechanisms of activation remain unknown. To explore immune reactions during cardiac remodeling, we applied a non-surgical model of coronary heart disease (CHD) induced by a high-fat diet (HFD-CHD) in SR-BI-/-/ApoeR61h/h mice. Flow cytometry analyses throughout the period of progressive cardiac dysfunction revealed that CD4+ T Helper 1 (Th1) cells were predominantly activated in T-cell subsets. Probucol was reported to attenuate cardiac dysfunction after coronary artery ligation model (ligation-MI) in rats. To determine whether probucol suppress cardiac remodeling after HFD-CHD, we treated SR-BI-/-/ApoeR61h/h mice with probucol. We found treatment with probucol in HFD-CHD mice reduced cardiac dysfunction, with attenuated activation of Th1 cells. RNA-seq analyses revealed that probucol suppressed the expression of CXCR3, a Th1-related chemokine receptor, in the heart. XCR1+ cDC1 cells, which highly expresses the CXCR3 ligands CXCL9 and CXCL10, were predominantly activated after HFD-CHD. XCR1+ cDC1 lineage skewing of pre-DC progenitors was observed in bone marrow, with subsequent systemic expansion of XCR1+ cDC1 cells after HFD-CHD. Activation of CXCR3+ Th1 cell and XCR1+ cDC1 cells was also observed in ligation-MI. Notably, post-MI depletion of XCR1+ cDC1 cells suppressed CXCR3+ Th1 cell activation and prevented cardiac dysfunction. In patient autopsy samples, CXCR3+ Th1 and XCR1+ cDC1 cells infiltrated the infarcted area. In this study, we identified a critical role of XCR1+ cDC1-activated CXCR3+ Th1 cells in ischemic cardiac remodeling.
Assuntos
Cardiopatias , Traumatismos Cardíacos , Camundongos , Ratos , Animais , Células Th1 , Probucol/metabolismo , Remodelação Ventricular , Cardiopatias/metabolismo , Células Dendríticas , Traumatismos Cardíacos/metabolismoRESUMO
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 (ï¼3,000 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.
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Hipertrigliceridemia , Púrpura Trombocitopênica Idiopática , Receptores de Lipoproteínas , Masculino , Humanos , Pessoa de Meia-Idade , Receptores de Lipoproteínas/química , Receptores de Lipoproteínas/genética , Receptores de Lipoproteínas/metabolismo , Lipase Lipoproteica/metabolismo , Apolipoproteína C-II/genética , Apolipoproteína C-II/metabolismo , Hipertrigliceridemia/genéticaRESUMO
Patients with psoriasis are at a higher risk of developing nonalcoholic fatty liver disease. We previously identified an oxidized derivative of cholesterol, 7-ketocholesterol (7KC), in diet-induced steatohepatitic mice. Here, we investigated whether 7KC exacerbates psoriasis-like dermatitis by accelerating steatohepatitis in mice. A high-fat/high-cholesterol/high-sucrose/bile salt diet (nonalcoholic steatohepatitis (NASH) diet) with or without 0.0125% 7KC was fed to C57BL/6 mice (7KC or control group) for three weeks to induce steatohepatitis. A 5% imiquimod cream was then applied to the ears and dorsal skin for four days to induce psoriasis-like dermatitis. Hepatic lipid accumulation and inflammatory cell infiltration were exacerbated in the 7KC group compared with the control group after three weeks. Serum tumor necrosis factor-α (TNF-α) levels were also elevated in the 7KC group (108.5 ± 9.8 vs. 83.1 ± 13.1 pg/mL, p < 0.005). Imiquimod cream increased the psoriasis area severity index (PASI) score in mice in the 7KC group (9.14 ± 0.75 vs. 5.17 ± 1.17, p < 0.0001). Additionally, Tnfa, Il23a, Il17a, and Il22 mRNA levels in the dorsal lesion were significantly upregulated. Finally, Th17 cell differentiation and the TNF signaling pathway were enhanced in the dorsal lesions and liver of mice in the 7KC group. These data suggest that steatohepatitis and psoriasis are linked by a potent, diet-related factor.
Assuntos
Dermatite , Hepatopatia Gordurosa não Alcoólica , Oxisteróis , Psoríase , Camundongos , Animais , Imiquimode/efeitos adversos , Camundongos Endogâmicos C57BL , Psoríase/induzido quimicamente , Cetocolesteróis , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Dieta Hiperlipídica , Modelos Animais de DoençasRESUMO
Although patients with nonalcoholic fatty liver disease have been reported to have cardiac dysfunction, and appropriate model has not been reported. We established a novel mouse model of diet-induced steatohepatitis-related cardiomyopathy and evaluated the effect of pemafibrate. C57Bl/6 male mice were fed a (1) chow diet (C), (2) high-fat, high-cholesterol, high-sucrose, bile acid diet (NASH diet; N), or (3) N with pemafibrate 0.1 mg/kg (NP) for 8 weeks. In the liver, macrophage infiltration and fibrosis in the liver was observed in the N group compared to the C group, suggesting steatohepatitis. Free cholesterol accumulated, and cholesterol crystals were observed. In the heart, free cholesterol similarly accumulated and concentric hypertrophy was observed. Ultrahigh magnetic field magnetic resonance imaging revealed that the left ventricular (LV) ejection fraction (EF) was attenuated and LV strain was focally impaired. RNA sequencing demonstrated that the NOD-like receptor and PI3 kinase-Akt pathways were enhanced. mRNA and protein expression of inflammasome-related genes, such as Caspase-1, NLRP3, and IL-1ß, were upregulated in both the liver and heart. In the NP compared to the N group, steatohepatitis, hepatic steatosis, and cardiac dysfunction were suppressed. Sequential administration of pemafibrate after the development of steatohepatitis-related cardiomyopathy recovered hepatic fibrosis and cardiac dysfunction.
Assuntos
Benzoxazóis/farmacologia , Butiratos/farmacologia , Cardiomiopatias/etiologia , Cardiomiopatias/metabolismo , Inflamassomos/metabolismo , Fígado/metabolismo , Miocárdio/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Animais , Benzoxazóis/administração & dosagem , Butiratos/administração & dosagem , Cardiomiopatias/tratamento farmacológico , Dieta Hiperlipídica/efeitos adversos , Carboidratos da Dieta/efeitos adversos , Modelos Animais de Doenças , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Inflamassomos/genética , Masculino , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológicoRESUMO
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, pï¼0.001) 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.
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Aterosclerose/metabolismo , Dislipidemias , Ensaio de Imunoadsorção Enzimática/métodos , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Lipoproteínas HDL , Oxirredução/efeitos dos fármacos , Probucol , Adulto , Antioxidantes/uso terapêutico , Dislipidemias/sangue , Dislipidemias/diagnóstico , Feminino , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/metabolismo , Hipolipemiantes/farmacocinética , Hipolipemiantes/uso terapêutico , Lipoproteínas HDL/análise , Lipoproteínas HDL/metabolismo , Masculino , Probucol/farmacocinética , Probucol/uso terapêutico , Reprodutibilidade dos TestesRESUMO
AIMS: Although intensive statin therapy reduced cardiovascular risks, cardiovascular events have not been completely prevented. Probucol is a potent antioxidant and reduces tendon xanthomas in familial hypercholesterolemia patients despite reduction of high-density lipoprotein (HDL)-cholesterol (HDL-C). We investigated whether probucol can reduce cardiovascular events on top of conventional lipid-lowering therapy in patients with coronary heart disease (CHD). METHODS: PROSPECTIVE is a multicenter, randomized, prospective study that recruited 876 Japanese patients with CHD and dyslipidemia with a low-density lipoprotein (LDL)-cholesterol (LDL-C) level of ≥ 140 mg/dL without medication or those treated with lipid-lowering drugs. Lipid-lowering agents were administered during the study period in the control group (n=438), and probucol 500 mg/day was added to lipid-lowering therapy in the probucol group (n=438). Patients were randomly assigned to two treatment groups by adjusting the LDL-C level and presence of diabetes and hypertension and followed up for more than 3 years. The primary end point was a composite of cerebrovascular and cardiovascular events (cardiovascular disease death including sudden death, nonfatal myocardial infarction, nonfatal stroke, hospitalization for unstable angina, hospitalization for heart failure, or coronary revascularization). The secondary end point was carotid intima-media thickness in a subset of patients. RESULTS: The incidence of the primary end point showed a trend to be lower in the probucol group compared with that in the control group despite reduced HDL-C without serious adverse events. Anti-atherogenic effects of probucol may be attributed to its potent antioxidative function and enhancement of reverse cholesterol transport. CONCLUSION: Since there was no statistical significance between the probucol and control groups despite a marked reduction of HDL-C, further studies on the clinical outcomes of probucol on top of conventional therapy may be necessary in the future (UMIN000003307).
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Doenças Cardiovasculares , HDL-Colesterol/sangue , Hiperlipidemias/tratamento farmacológico , Probucol , Acidente Vascular Cerebral , Idoso , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/efeitos adversos , Antioxidantes/administração & dosagem , Antioxidantes/efeitos adversos , Transporte Biológico/efeitos dos fármacos , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/prevenção & controle , Espessura Intima-Media Carotídea , LDL-Colesterol/sangue , Monitoramento de Medicamentos/métodos , Feminino , Humanos , Hiperlipidemias/sangue , Masculino , Probucol/administração & dosagem , Probucol/efeitos adversos , Prevenção Secundária/métodos , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Resultado do TratamentoRESUMO
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.
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Colesterol na Dieta/administração & dosagem , Cetocolesteróis/administração & dosagem , Fígado/metabolismo , Macrófagos/metabolismo , Obesidade/metabolismo , Oxisteróis/administração & dosagem , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Colesterol na Dieta/efeitos adversos , Mediadores da Inflamação/metabolismo , Cetocolesteróis/efeitos adversos , Fígado/efeitos dos fármacos , Fígado/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Camundongos , Camundongos Obesos , Obesidade/patologia , Oxisteróis/efeitos adversosRESUMO
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 ß-catenin protein expression levels were also observed in the hearts of aged PGRN KO mice. Treatment of PGRN-deficient cardiomyocytes with C1q caused ß-catenin activation and cardiac hypertrophy. Blocking C1q-induced ß-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 ß-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 ß-catenin activation. PGRN is a potential therapeutic target to prevent cardiac hypertrophy and dysfunction.
Assuntos
Envelhecimento/metabolismo , Cardiomegalia/metabolismo , Complemento C1q/metabolismo , Progranulinas/deficiência , beta Catenina/metabolismo , Animais , Aorta/patologia , Biomarcadores/metabolismo , Cardiomegalia/patologia , Cardiomegalia/fisiopatologia , Constrição Patológica , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miocárdio/metabolismo , Miocárdio/patologia , Miocárdio/ultraestrutura , Miócitos Cardíacos/metabolismo , Fenótipo , Pressão , Progranulinas/metabolismo , Ratos , Transdução de SinaisRESUMO
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.
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Cardiomiopatias/prevenção & controle , Dieta/efeitos adversos , Modelos Animais de Doenças , Inibidores do Fator Xa/farmacologia , Infarto do Miocárdio/complicações , Isquemia Miocárdica/prevenção & controle , Rivaroxabana/farmacologia , Animais , Cardiomiopatias/etiologia , Cardiomiopatias/patologia , Progressão da Doença , Masculino , Camundongos , Camundongos Knockout , Camundongos Knockout para ApoE , Infarto do Miocárdio/patologia , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/patologia , Receptores Depuradores Classe B/fisiologiaRESUMO
BACKGROUND: We previously reported that the patients with cholesteryl ester transfer protein (CETP) deficiency (CETP-D) show marked changes in the size and lipid compositions of high-density lipoprotein (HDL) and that they are not protected from atherosclerotic cardiovascular diseases, despite increased serum HDL-cholesterol (HDL-C) levels. HDL particles carry a variety of proteins, some of which are known to have antiatherogenic functions. OBJECTIVE: This study aimed to investigate the protein composition of HDL particles in patients with CETP-D. METHODS: Eight patients with complete deficiency of CETP and 8 normolipidemic healthy subjects were enrolled. We performed shotgun proteomic analysis to investigate the proteome of ultracentrifugally isolated HDL. RESULTS: We identified 79 HDL-associated proteins involved in lipid metabolism, protease inhibition, complement regulation, and acute-phase response, including 5 potential newly identified HDL-associated proteins such as angiopoietin-like3 (ANGPTL3). Spectral counts of apolipoprotein (apo) E were increased in patients with CETP-D compared with controls (60.3 ± 6.9 vs 43.7 ± 2.5, P < .001), which is concordant with our previous report. Complement regulatory proteins such as C3, C4a, C4b, and C9 were also significantly enriched in HDL from patients with CETP-D. Furthermore, apoC-III and ANGPTL3, both of which are now known to associate with increased atherosclerotic cardiovascular diseases, were enriched in patients with CETP-D compared with normolipidemic subjects (35.9 ± 5.3 vs 27.1 ± 3.7, 2.3 ± 1.1 vs 0.4 ± 1.1, respectively; P < .01). CONCLUSION: We have characterized HDL-associated proteins in patients with CETP-D. We identified a significant increase in the amount of apoE, apoC-III, ANGPTL3, and complement regulatory proteins. These proteomic changes might be partly responsible for the enhanced atherogenicity of patients with CETP-D.
Assuntos
Proteínas de Transferência de Ésteres de Colesterol/deficiência , Erros Inatos do Metabolismo Lipídico/metabolismo , Lipoproteínas HDL/metabolismo , Proteômica , Reação de Fase Aguda/complicações , Proteínas de Transferência de Ésteres de Colesterol/sangue , Proteínas de Transferência de Ésteres de Colesterol/metabolismo , Proteínas do Sistema Complemento/metabolismo , Feminino , Humanos , Erros Inatos do Metabolismo Lipídico/sangue , Erros Inatos do Metabolismo Lipídico/complicações , Erros Inatos do Metabolismo Lipídico/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Inibidores de Proteases/farmacologia , Inibidores de Proteases/uso terapêuticoRESUMO
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.
Assuntos
Antígenos CD36/genética , Proteínas de Transporte de Ácido Graxo/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Disfunção Ventricular Esquerda/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Antígenos CD36/fisiologia , Metabolismo Energético/fisiologia , Fibrose , Glucose/metabolismo , Hipertrofia Ventricular Esquerda/complicações , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miocárdio/patologia , Miócitos Cardíacos/patologia , Pressão/efeitos adversos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Remodelação VentricularRESUMO
Progranulin (PGRN) has been reported to be associated with cell proliferation, cell growth, wound healing, and inflammation. PGRN mutations are known to be related to dementia. However, the association between PGRN and atherosclerosis remains to be elucidated. Therefore, we generated PGRN-/-ApoE-/- mice to analyze the effect of PGRN on the development of atherosclerosis.
Assuntos
Aterosclerose/metabolismo , Biologia Molecular/métodos , Progranulinas/metabolismo , Animais , Colesterol/metabolismo , Modelos Animais de Doenças , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Lipoproteínas LDL/metabolismo , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Apolipoprotein E (ApoE) plays crucial roles not only in lipid metabolism but also in bone metabolism. Specifically ApoE4, one of major ApoE isoforms, has been demonstrated to be associated with increased risk of developing osteoporosis compared to another major isoform ApoE3. However, the detailed mechanism of how the different ApoE isoforms affect bone metabolism remains unclear. Micro-CT analyses of distal femora demonstrated severely decreased bone mass in 48-week-old female homozygous ApoE-knockout (ApoE-KO) mice compared to age- and gender-matched wild type C57BL/6â¯J (WT) mice. Physiological levels of either ApoE3 or ApoE4 protein (1-20⯵g/ml) significantly increased the expression of osteoblast-related genes and alkaline phosphatase (ALP) activity of primary calvarial osteoblasts by inhibiting extracellular signal-regulated kinase 1/2 (ERK1/2) pathway in a dose-dependent manner, and ApoE3 showed greater osteoblastic induction compared to ApoE4. Furthermore, both ApoE3 and ApoE4 protein inhibited osteoclastogenesis and the expression of osteoclast-related genes of mouse bone marrow derived macrophages (BMDM) via down regulation of c-Fos, nuclear factor of activated T-cells 1 (NFATc1) and nuclear factor-kappa B (NF-κB) pathway. Moreover, ApoE3 showed greater inhibition of c-Fos, dendritic cell-specific transmembrane protein (DC-STAMP), and Cathepsin K gene expression compared to ApoE4. Collectively, ApoE plays crucial roles in preserving bone mass, suggesting that targeting ApoE and its isoforms as a promising treatment candidate of both osteoporosis and hyperlipidemia.
Assuntos
Apolipoproteínas E/metabolismo , Osteoblastos/patologia , Osteoclastos/patologia , Osteoporose/metabolismo , Osteoporose/patologia , Transdução de Sinais , Animais , Apolipoproteínas E/genética , Diferenciação Celular , Feminino , Sistema de Sinalização das MAP Quinases , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteoclastos/citologia , Osteoclastos/metabolismo , Osteogênese , Osteoporose/genética , Proteínas Proto-Oncogênicas c-fos/metabolismoRESUMO
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.
Assuntos
Aterosclerose/etiologia , Aterosclerose/patologia , Índice de Gravidade de Doença , Doença de Tangier/complicações , Humanos , Masculino , Pessoa de Meia-Idade , PrognósticoRESUMO
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<0.001), whereas the PN of very small LDL, which is known to be atherogenic, was significantly higher (1.36-fold increase, p = 0.016). The PNs of very large and large HDL in CETP-D were markedly higher than that in healthy subjects (19.9- and 4.5-fold increase, respectively; p<0.001), whereas the PNs of small and very small HDL, which have more potent anti-atherogenic functions, were significantly lower (0.76- and 0.61-fold decrease, respectively; p<0.001). CONCLUSION: We have assessed the PNs of detailed subclasses of patients with CETP-D for the first time. The PN of larger HDL was markedly increased, that of smaller HDL was decreased, and that of very small LDL was increased, suggesting that CETP-D has pro-atherogenic lipoprotein properties.
Assuntos
Proteínas de Transferência de Ésteres de Colesterol/deficiência , Cromatografia em Gel/métodos , Cromatografia Líquida de Alta Pressão/métodos , Erros Inatos do Metabolismo Lipídico/sangue , Lipoproteínas/classificação , Adulto , Proteínas de Transferência de Ésteres de Colesterol/sangue , Feminino , Humanos , Lipoproteínas/sangue , Masculino , Pessoa de Meia-IdadeRESUMO
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.
Assuntos
Dieta Hiperlipídica/efeitos adversos , Fenofibrato/farmacologia , Hipertrigliceridemia/prevenção & controle , Hipolipemiantes/farmacologia , PPAR gama/metabolismo , Animais , Quilomícrons/metabolismo , Hipertrigliceridemia/etiologia , Hipertrigliceridemia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Período Pós-PrandialRESUMO
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 ï¼8.4%), 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 (ï¼7.4%). 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, pï¼0.01) and non-HDL-C (129±29 vs. 116±20 mg/dl, pï¼0.01) in combination with glucose (150±47 vs. 129±27 mg/dl, pï¼0.01) and HbA1c (7.1±0.6 vs. 6.6±0.7 mg/dl, pï¼0.001). Sitagliptin also significantly decreased the fasting levels of apolipoprotein (apo) B-48 (7.8±6.7 vs. 5.6±4.0 µg/ml, pï¼0.01), remnant lipoprotein cholesterol (15.3±9.5 vs. 12.0±7.9 mg/dl, pï¼0.05) 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).