RESUMO
Kgengwe fruits are commonly consumed in sub-Saharan countries. Recent reports indicated low coronary artery disease rates in those regions. To investigate anti-atherogenic properties and potential mechanisms of action of Kgengwe seed powder (KSP), male low-density lipoprotein receptor knockout (LDL-r-KO) mice were fed with an atherogenic diet supplemented with (treated, n = 10) or without (controls, n = 10) 10% (w/w) KSP for 20 weeks. Proximate analysis revealed that KSP contained 38% fibre and 15% lipids. KSP supplementation was not associated with significant changes in body weight gain rate, food intake, and plasma lipid levels. However, the average atherosclerotic lesion size in the aortic roots in the KSP-treated group was 58% smaller than that in the control group (0.26 vs 0.11 mm2, p < 0.05). This strong anti-atherogenic effect was associated with significant increases in the average plasma levels of certain cytokines such as IL-10 (6 vs 13 pg/mL, p < 0.05), GM-CSF (0.1 vs 0.2 pg/mL, p < 0.05), and EPO (7 vs 16 pg/mL, p < 0.05) along with reductions in the average levels of plasma MCP-1 (19 vs 14 pg/mL, p < 0.05) and MIP-2 (28 vs 13 pg/mL, p < 0.05). Except for relatively high levels of saturated fatty acids, KSP possesses balanced nutrient compositions with strong anti-atherogenic properties, which may be mediated through alterations in inflammatory pathways. Additional studies warrant confirmation and mechanism(s) of action of such effects. Novelty: Kgengwe seeds prevent atherogenesis in LDL-r-KO mice. Kgengwe seeds increase circulating levels of IL-10 and EPO. No reduction in plasma total cholesterol levels.
Assuntos
Aterosclerose/prevenção & controle , Citrullus , Placa Aterosclerótica/prevenção & controle , Sementes , Animais , Aterosclerose/sangue , Peso Corporal , Colesterol/sangue , Citrullus/química , Citocinas/sangue , Modelos Animais de Doenças , Ingestão de Alimentos , Ácidos Graxos/análise , Inflamação/prevenção & controle , Masculino , Camundongos Knockout , Tamanho do Órgão , Placa Aterosclerótica/sangue , Placa Aterosclerótica/patologia , Pós , Receptores de LDL , Triglicerídeos/sangueRESUMO
BACKGROUND: The HMG-CoA reductase is key enzyme of cholesterol biosynthesis which potentially contributes in management of hypercholesterolemia. The present study was designed to assess the inhibitory effect of phytoconstituents of an ethanolic extract of Prosopis cineraria pods on HMG - CoA reductase and regression potential of atherosclerotic plaque. METHODS: Healthy, adult male, albino rabbits in which hypercholesterolemia was induced by supplying the high fat diet and a supplement of cholesterol powder with coconut oil (500 mg/5 ml/Day/kg body weight) for 15 days, were used as a disease model. Phytochemical analysis of an ethanolic extract Prosopis cineraria pods was conducted using LCMS, GCMS and FTIR analysis. Further, in-vitro, in-vivo and in-silico assessments were performed. RESULTS: The in-vitro assessment of HMG -CoA reductase activity indicated a 67.1 and 97.3% inhibition by the extract and a standard drug (Pravastatin), respectively. Additionally, an in-silico evaluation was made using appropriate docking software and results also indicated as significant interactions of the identified compounds with the target enzyme. Treatment of rabbits with the ethanolic extract of P. cineraria pod resulted in significant (P ≤ 0.001) reductions in total cholesterol, LDL cholesterol, VLDL cholesterol, and triglyceride. Accordingly, reductions were occurred in atherosclerotic plaque, intima and media of aortal wall along with lumen volume of the aorta significantly increased (P ≤ 0.001). CONCLUSION: It can be illustrating that the ethanolic extract of Prosopis cineraria pod contains potent bioactive phytocompounds might be inhibit HMG - CoA reductase and have regression potential of atherosclerotic plaque.
Assuntos
Anticolesterolemiantes/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Placa Aterosclerótica/tratamento farmacológico , Prosopis/química , Animais , Anticolesterolemiantes/química , HDL-Colesterol/sangue , LDL-Colesterol/sangue , VLDL-Colesterol/sangue , Modelos Animais de Doenças , Hidroximetilglutaril-CoA Redutases/genética , Inibidores de Hidroximetilglutaril-CoA Redutases/química , Hipercolesterolemia/tratamento farmacológico , Masculino , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Placa Aterosclerótica/sangue , Placa Aterosclerótica/patologia , Pravastatina/farmacologia , Coelhos , Triglicerídeos/sangueRESUMO
BACKGROUND: ATP-binding cassette A1 (ABCA1) and G1 (ABCG1) mediate cholesterol efflux from lipid-laden macrophages, thus promoting anti-atherosclerotic outcomes. The mechanism(s) linking treatment with statins and ABCA1/ABCG1 in human atherosclerosis are not fully understood and require further investigation. Therefore, we studied whether short-term treatment with low- or high-dose rosuvastatin may affect ABCA1 and ABCG1 expression in human atherosclerotic plaques. METHODS: Seventy patients with severe stenosis of the internal carotid artery were randomized to receive low (10â¯mg/day) or high (40â¯mg/day) dose rosuvastatin for 12â¯weeks before elective endarterectomy. As controls, we analyzed a reference group of 10 plaques from subjects with hypercholesterolemia but not receiving statin treatment and an additional set of 11 plaques collected from normocholesterolemic patients. On atherosclerotic plaques, ABCA1 and ABCG1 expression was evaluated at RNA level by qPCR and at protein level by immunoblotting and immunohistochemistry. RESULTS: Both rosuvastatin doses were associated with lower plaque ABCA1 mRNA levels and with a trend toward reduction for ABCG1. However, ABCA1 protein was paradoxically higher in patients treated with high-dose rosuvastatin and was associated with lower levels of miR-33b-5p, a microRNA known as a regulator of ABCA1. Multivariate analyses showed that the effect is cholesterol-independent. Finally, no effects were found for ABCG1 protein. CONCLUSIONS: High-dose rosuvastatin increases macrophage ABCA1 protein levels in human atherosclerotic plaque despite mRNA reduction in a mechanism unrelated to plasma cholesterol reduction and potentially involving miR-33b-5p. This pathway may reflect an additional feature contributing to the anti-atherosclerotic effect for high-dose rosuvastatin. TRIAL REGISTRATION: ISRCTN16590640.
Assuntos
Transportador 1 de Cassete de Ligação de ATP/sangue , Colesterol/sangue , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Placa Aterosclerótica/sangue , Placa Aterosclerótica/tratamento farmacológico , Rosuvastatina Cálcica/administração & dosagem , Transportador 1 de Cassete de Ligação de ATP/biossíntese , Idoso , Idoso de 80 Anos ou mais , Anticolesterolemiantes/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Humanos , MasculinoRESUMO
BACKGROUND AND AIMS: Higher blood levels of the omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have been associated with fewer cardiovascular events and lower mortality in prospective studies. Our aim was to determine a target level of EPA and DHA to prevent progression of coronary artery plaque. METHODS: 218 subjects with stable coronary artery disease on statins were randomized to high-dose EPA and DHA (3.36 g daily) or no omega-3 for 30 months. Coronary plaque volume was measured by coronary computed tomographic angiography. Plasma phospholipid levels of EPA, DHA and total fatty acids were measured by gas chromatography mass spectrometry. The omega-3 fatty acid index was calculated as EPA+DHA/total fatty acid. RESULTS: Mean (SD) age was 62.9 (7.8) years; mean (SD) LDL-C level 78.6 (27.3) mg/dL and median triglyceride level 122â¯mg/dL. Subjects assigned to EPA and DHA had increased plasma EPA and DHA levels variably from 1.85% to 13.02%. Plasma omega-3 fatty acid index ≥4% prevented progression of fibrous, noncalcified, calcified and total plaque in nondiabetic subjects whereas those in the lowest quartile (<3.43%) had significant progression of fibrous, calcified and total plaque. No difference was observed in diabetic subjects. CONCLUSIONS: EPA and DHA added to statins prevented coronary plaque progression in nondiabetic subjects with mean LDL-C <80â¯mg/dL, when an omega-3 index ≥4% was achieved. Low omega-3 index <3.43% identified nondiabetic subjects at risk of coronary plaque progression despite statin therapy. These findings highlight the importance of measuring plasma levels of omega-3 fatty acids early and at trial conclusion. Targeting an omega-3 index ≥4% maximizes cardiovascular benefit.
Assuntos
Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/tratamento farmacológico , Ácidos Docosa-Hexaenoicos/sangue , Ácido Eicosapentaenoico/sangue , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Placa Aterosclerótica/sangue , Idoso , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/prevenção & controle , Progressão da Doença , Ácidos Docosa-Hexaenoicos/fisiologia , Ácido Eicosapentaenoico/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/complicações , Placa Aterosclerótica/prevenção & controleRESUMO
BACKGROUND: There is a crosstalk between endoplasmic reticulum stress (ERS) and autophagy, and autophagy could attenuate endoplasmic reticulum stress-mediated apoptosis. Ginkgo biloba leaf extract (GBE) exerts vascular protection functions. The purpose of the present study is to investigate the role of autophagy in diabetic atherosclerosis (AS) and the effect of GBE on autophagy and ERS. METHODS: Network pharmacology was utilized to predict the targets and pathways of the active chemical compounds of Gingko biloba leaf to attenuate AS. ApoE-/- mice were rendered diabetic by intraperitoneal ingestion with streptozotocin combined with a high-fat diet. The diabetic mice were divided into five groups: model group, atorvastatin group, rapamycin group, and low- and high-dose GBE groups. Serum and tissue markers of autophagy or ERS markers, including the protein expression, were examined. RESULTS: The mammalian target of rapamycin (mTOR) and NF-κB signaling pathways were targeted by the active chemical compounds of GBE to attenuate AS predicted by network pharmacology. GBE reduced the plaque area/lumen area and the plaque lipid deposition area/intimal area and inhibited the expressions of CD68, MMP2, and MMP9. Rapamycin and GBE inhibited the expression of mTOR and SQSTM1/p62 which increased in the aorta of diabetic mice. In addition, GBE reduced the expression of ERS markers in diabetic mice. GBE reduced the serum lipid metabolism levels, blood glucose, and inflammatory cytokines. CONCLUSION: Impaired autophagy and overactive endoplasmic reticulum stress contributed to diabetic atherosclerosis. mTOR inhibitor rapamycin and GBE attenuated diabetic atherosclerosis by inhibiting ERS via restoration of autophagy through inhibition of mTOR.
Assuntos
Apolipoproteínas E/deficiência , Aterosclerose/tratamento farmacológico , Autofagia , Diabetes Mellitus Experimental/tratamento farmacológico , Estresse do Retículo Endoplasmático , Extratos Vegetais/uso terapêutico , Serina-Treonina Quinases TOR/metabolismo , Animais , Aterosclerose/sangue , Autofagia/efeitos dos fármacos , Glicemia/metabolismo , Peso Corporal , Colágeno/metabolismo , Citocinas/sangue , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ginkgo biloba , Mediadores da Inflamação/sangue , Lipídeos/sangue , Masculino , Camundongos Endogâmicos C57BL , Modelos Biológicos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Placa Aterosclerótica/sangue , Placa Aterosclerótica/patologia , Transdução de SinaisRESUMO
BACKGROUND: Atherosclerosis (AS) is mainly responsible for cardiovascular diseases. The present study investigated whether Lipingshu capsule (LPS), whose ingredients are present in health food stores, has beneficial effect on AS. METHODS: C57BL/6 J mice were given a low fat rodent diet and assigned as control group (CON). ApoE-/- mice were placed on high fat rodent diet and randomly separated into high fat diet (HFD) group and HFD + LPS group whose animals were given 0.9 g/kg.BW LPS daily for 10 weeks. Atherosclerotic lesions in aorta and aortic root were evaluated. Serum lipids and multiple cytokine were measured. RESULTS: ApoE-/- mice fed with high fat diet had serious aortic lesions, whereas LPS markedly decreased plaque area of the total aorta and of the aortic root. LPS recovered the serum lipid profiles by substantially reducing TC, LDL-C, TG and Ox-LDL contents. Multi-cytokine analysis revealed greater serum levels of IL-1α, IL-1ß, IL-6, IFN-γ, GMCSF, RANTES and TNF-α induced by high fat diet slumped with LPS treatment. CONCLUSION: LPS reduces atherosclerotic lesions and thus alleviates AS by lipid profile modulation and inflammation inhibition.
Assuntos
Anti-Inflamatórios/farmacologia , Apolipoproteínas E/deficiência , Aterosclerose/tratamento farmacológico , Fármacos Cardiovasculares/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Placa Aterosclerótica/tratamento farmacológico , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aorta/patologia , Apolipoproteínas E/genética , Aterosclerose/sangue , Aterosclerose/etiologia , Aterosclerose/patologia , Cápsulas , Quimiocina CCL5/antagonistas & inibidores , Quimiocina CCL5/biossíntese , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Citocinas/antagonistas & inibidores , Citocinas/biossíntese , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Humanos , Lipoproteínas LDL/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Extratos Vegetais/química , Placa Aterosclerótica/sangue , Placa Aterosclerótica/etiologia , Placa Aterosclerótica/patologia , Resultado do Tratamento , Triglicerídeos/sangue , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossínteseRESUMO
BACKGROUND: Epigallocatechin-3-gallate (EGCG), which is the principal component of green tea, has been shown to prevent atherosclerosis. However, the effect of EGCG on atherosclerotic plaque stability remains unknown. AIM: This study aimed to assess whether EGCG can enhance atherosclerotic plaque stability and to investigate the underlying mechanisms. METHODS: Apolipoprotein E-deficient mice fed a high-fat diet were injected intraperitoneally with EGCG (10 mg/kg) for 16 weeks. Cross sections of the brachiocephalic arteries were stained with haematoxylin and eosin for morphometric analyses or Masson's trichrome for collagen content analyses. Immunohistochemistry was performed to evaluate the percentage of macrophages and smooth muscle cells (SMCs). Protein expression and matrix metalloproteinase (MMP) activity were assayed by Western blot and gelatin zymography, respectively. Serum inflammatory cytokine levels were quantified by enzyme-linked immunosorbent assays. RESULTS: After 16 weeks of feeding the high-fat diet, there were clear atherosclerotic lesions in the proximal brachiocephalic artery segments according to HE staining. EGCG treatment significantly increased the thickness of the fibrous cap. In the atherosclerotic plaques of the EGCG group, the relative macrophage content was decreased, whereas the relative SMC and collagen contents were increased. The expression levels of MMP-2, MMP-9, and extracellular matrix metalloproteinase inducer (EMMPRIN) were significantly decreased by EGCG treatment. In addition, EGCG treatment decreased the circulat-ing tumour necrosis factor-α, interleukin-6, monocyte chemoattractant protein-1, and interferon-γ levels in apolipoprotein E-deficient mice. CONCLUSIONS: EGCG promotes atherosclerotic lesion stability in apolipoprotein E-deficient mice. Potentially, these effects are mediated through the inhibition of inflammatory cytokine, MMPs and EMMPRIN expression.
Assuntos
Basigina/genética , Catequina/análogos & derivados , Citocinas/sangue , Metaloproteinases da Matriz/genética , Placa Aterosclerótica/tratamento farmacológico , Animais , Apolipoproteínas E/genética , Catequina/farmacologia , Catequina/uso terapêutico , Dieta Hiperlipídica , Regulação da Expressão Gênica , Inflamação/sangue , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Miócitos de Músculo Liso/metabolismo , Placa Aterosclerótica/sangue , Placa Aterosclerótica/metabolismo , Chá/químicaRESUMO
Atherosclerosis (AS) is the main cause of cardiovascular diseases. This study investigated Yirui (YR) capsules, whose ingredients are available in health food stores, against AS and the underlying mechanisms. Male apolipoprotein E-deficient mice fed a high-fat diet for 10 weeks developed severe aortic lesions, but YR significantly decreased the plaque area in the total aorta and aortic root. YR affected the serum lipid profile by significantly reducing total cholesterol, low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), and oxidative modification of LDL-C (Ox-LDL) levels. In addition, multi-cytokine analysis revealed that higher serum levels of interleukin-1 alpha (IL-1α), interleukin-1 beta (IL-1ß), interleukin-3 (IL-3), interleukin-6 (IL-6), interleukin-27 (IL-27), tumor necrosis factor alpha, interferon gamma, and regulated on activation, normal T cell expressed and secreted (RANTES), which were induced by a high-fat diet, declined with YR treatment. These results suggest that YR reduces the atherosclerotic plaque burden, thereby alleviating AS by modulating the lipid profile and inhibiting inflammation.
Assuntos
Aterosclerose/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Inflamação/tratamento farmacológico , Animais , Aterosclerose/sangue , Quimiocinas/sangue , Colesterol/sangue , Citocinas/sangue , Dieta Hiperlipídica/efeitos adversos , Inflamação/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Placa Aterosclerótica/sangue , Placa Aterosclerótica/tratamento farmacológico , Placa Aterosclerótica/etiologia , Triglicerídeos/sangueRESUMO
BACKGROUND: Although statins reduce cardiovascular events, residual risk remains. Therefore, additional modalities are needed to reduce risk. We evaluated the effect of eicosapentaenoic acid and docosahexaenoic acid in pharmacologic doses added to statin treatment on coronary artery plaque volume. METHODS AND RESULTS: A total of 285 subjects with stable coronary artery disease on statins were randomized to omega-3 ethyl-ester (1.86 g of eicosapentaenoic acid and 1.5 g of docosahexaenoic acid daily) or no omega-3 (control) for 30 months. Coronary plaque volume was assessed by coronary computed tomographic angiography. Mean (SD) age was 63.0 (7.7) years; mean low-density lipoprotein cholesterol ≤80 mg/dL. In the intention-to-treat analysis, our primary endpoint, noncalcified plaque volume, was not different between groups (P=0.14) but approached significance in the per protocol analysis (P=0.07). When stratified by age in the intention-to-treat analysis, younger omega-3 subjects had significantly less progression of the primary endpoint, noncalcified plaque (P=0.013), and fibrous, calcified and total plaque. In plaque subtype analysis, controls had significant progression of fibrous plaque compared to no change in the omega-3 ethyl-ester group (median % change [interquartile range], 5.0% [-5.7, 20.0] versus -0.1% [-12.3, 14.5], respectively; P=0.018). Among those on low-intensity statins, omega-3 ethyl-ester subjects had attenuation of fibrous plaque progression compared to controls (median % change [interquartile range], 0.3% [-12.8, 9.0] versus 4.8% [-5.1, 19.0], respectively; P=0.032). In contrast, those on high-intensity statins had no difference in plaque change in either treatment arm. CONCLUSIONS: High-dose eicosapentaenoic acid and docosahexaenoic acid provided additional benefit to statins in preventing progression of fibrous coronary plaque in subjects adherent to therapy with well-controlled low-density lipoprotein cholesterol levels. The benefit on low-intensity statin, but not high-intensity statin, suggests that statin intensity affects plaque volume. CLINICAL TRIAL REGISTRATION: URL: http://www.ClinicalTrials.gov. Unique identifier: NCT01624727.
Assuntos
Doença da Artéria Coronariana/tratamento farmacológico , Vasos Coronários/diagnóstico por imagem , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácido Eicosapentaenoico/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Placa Aterosclerótica/tratamento farmacológico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico , Vasos Coronários/efeitos dos fármacos , Progressão da Doença , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/sangue , Placa Aterosclerótica/diagnóstico , Fatores de Risco , Resultado do Tratamento , Adulto JovemRESUMO
OBJECTIVE: Rice bran is a by-product of rice milling and is rich in bioactive molecules such as γ-oryzanol, phytosterols, and tocotrienols. The rice bran enzymatic extract (RBEE) previously showed vessel remodeling prevention and lipid-lowering, antioxidant, anti-inflammatory, and antiapoptotic activities. The aim of this study was to identify RBEE hypolipidemic mechanisms and to study the effects of RBEE on the progression of atherosclerosis disease and linked vascular dysfunction and liver steatosis in apolipoprotein E-knockout (ApoE-/-) mice fed low- or high-fat (LFD, HFD, respectively) and cholesterol diets. METHODS: ApoE-/- mice were fed LFD (13% kcal) or HFD (42% kcal) supplemented or not supplemented with 1 or 5% RBEE (w/w) for 23 wk. Then, serum, aorta, liver, and feces were collected and flash frozen for further analysis. RESULTS: RBEE supplementation of HFD improved serum values by augmenting high-density lipoprotein cholesterol and preventing total cholesterol and aspartate aminotransferase increase. 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase activity was attenuated (1 and 5% RBEE) and cholesterol excretion increased (5% RBEE). Diet supplementation with 5% RBEE reduced plaque development regardless of the diet. In HFD-fed mice, both doses of RBEE reduced lipid deposition and macrophage infiltration in the aortic sinus and downregulated intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 expression. None of these effects was observed in mice fed LFD. Liver steatosis was reduced by RBEE supplementation of LFD (1% RBEE) and HFD (1 and 5% RBEE) and nuclear peroxisome proliferator-activated receptor-α expression upregulated in the HDF 5% RBEE group. CONCLUSION: Regular consumption of RBEE-supplemented HFD reduced plaque development and liver steatosis by decreasing inflammation and hyperlipidemia through an HMG-CoA reductase activity and lipid excretion-related mechanism.
Assuntos
Dieta Hiperlipídica , Fibras na Dieta/farmacologia , Fígado Gorduroso/tratamento farmacológico , Extratos Vegetais/farmacologia , Placa Aterosclerótica/tratamento farmacológico , Acil Coenzima A/sangue , Animais , Antioxidantes/administração & dosagem , Aspartato Aminotransferases/sangue , Colesterol na Dieta/administração & dosagem , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Fígado Gorduroso/sangue , Inflamação/sangue , Inflamação/tratamento farmacológico , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Lipídeos/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , PPAR alfa/genética , PPAR alfa/metabolismo , Fenilpropionatos/administração & dosagem , Fitosteróis/administração & dosagem , Placa Aterosclerótica/sangue , Tocotrienóis/administração & dosagem , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismoRESUMO
Background: Vitamin D deficiency, defined as a serum 25-hydroxyvitamin D [25(OH)D] concentration <20 ng/mL, is correlated with a more atherogenic lipid profile. However, oral vitamin D supplementation does not lower LDL-cholesterol concentrations or raise HDL-cholesterol concentrations. This uncoupling between association and causation may result from a failure of oral vitamin D to mimic the effect of dermally synthesized vitamin D in response to ultraviolet type B (UVB) light.Objective: We tested the hypothesis that, in vitamin D-deficient adults, the replenishment of vitamin D with UVB exposure would lower LDL-cholesterol concentrations compared with the effect of oral vitamin D3 supplementation.Design: We performed a randomized clinical trial in vitamin D-deficient adults and compared vitamin D replenishment between subjects who received oral vitamin D3 (n = 60) and those who received narrow-band UVB exposure (n = 58) ≤6 mo.Results: There was no difference in the change from baseline LDL-cholesterol concentrations between oral vitamin D3 and UVB groups (difference in median of oral vitamin D3 minus that of UVB: 1.5 mg/dL; 95% CI: -5.0, 7.0 mg/dL). There were also no differences within groups or between groups for changes in total or HDL cholesterol or triglycerides. Transcriptional profiling of skin and blood, however, revealed significant upregulation of immune pathway signaling with oral vitamin D3 but significant downregulation with UVB.Conclusions: Correcting vitamin D deficiency with either oral vitamin D3 or UVB does not improve the lipid profile. Beyond cholesterol, these 2 modalities of raising 25(OH)D have disparate effects on gene transcription. This trial was registered at clinicaltrials.gov as NCT01688102.
Assuntos
Colesterol/sangue , Suplementos Nutricionais , Pele/metabolismo , Transcrição Gênica/efeitos dos fármacos , Raios Ultravioleta , Deficiência de Vitamina D/complicações , Vitamina D/farmacologia , Adulto , Colecalciferol/sangue , Colecalciferol/farmacologia , Colecalciferol/uso terapêutico , LDL-Colesterol/sangue , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Sistema Imunitário , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/sangue , Placa Aterosclerótica/etiologia , Transdução de Sinais , Pele/efeitos da radiação , Vitamina D/análogos & derivados , Vitamina D/biossíntese , Vitamina D/sangue , Vitamina D/uso terapêutico , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/tratamento farmacológico , Vitaminas/sangue , Vitaminas/farmacologia , Vitaminas/uso terapêuticoRESUMO
BACKGROUND: Despite extensive evidence demonstrating the beneficial effects of statins on clinical outcomes, the mechanisms underlying these effects remain elusive. OBJECTIVES: This study assessed changes in plaque morphology using intravascular imaging, with a comprehensive evaluation of cholesterol efflux capacity (CEC) and peripheral blood mononuclear cell (PBMC) transcriptomics in patients receiving high-dose statin therapy. METHODS: In a prospective study, 85 patients with stable coronary artery disease underwent percutaneous coronary intervention for a culprit lesion, followed by intracoronary multimodality imaging, including optical coherence tomography (OCT) of an obstructive nonculprit lesion. All subjects received 40 mg of rosuvastatin daily for 8 to 12 weeks, when the nonculprit lesion was reimaged and intervention performed. Blood samples were drawn at both times to assess CEC and transcriptomic profile in PBMC. RESULTS: Baseline OCT minimal fibrous cap thickness (FCT) was 100.9 ± 41.7 µm, which increased to 108.6 ± 39.6 µm at follow-up, and baseline CEC was 0.81 ± 0.14, which increased at follow-up to 0.84 ± 0.14 (p = 0.003). Thin-cap fibroatheroma prevalence decreased from 20.0% to 7.1% (p = 0.003). Changes in FCT were independently associated with CEC increase by multivariate analysis (ß: 0.30; p = 0.01). PBMC microarray analysis detected 117 genes that were differentially expressed at follow-up compared to baseline, including genes playing key roles in cholesterol synthesis (SQLE), regulation of fatty acids unsaturation (FADS1), cellular cholesterol uptake (LDLR), efflux (ABCA1 and ABCG1), and inflammation (DHCR24). Weighted coexpression network analysis revealed unique clusters of genes associated with favorable FCT and CEC changes. CONCLUSIONS: The study demonstrated an independent association between fibrous cap thickening and improved CEC that may contribute to morphological changes suggesting plaque stabilization among patients taking intensive statin therapy. Furthermore, the significant perturbations in PBMC transcriptome may help determine the beneficial effects of statin on plaque stabilization. (Reduction in Coronary Yellow Plaque, Lipids and Vascular Inflammation by Aggressive Lipid Lowering [YELLOW II]; NCT01837823).
Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Intervenção Coronária Percutânea , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/terapia , Doença da Artéria Coronariana/sangue , Dessaturase de Ácido Graxo Delta-5 , Feminino , Humanos , Leucócitos Mononucleares , Masculino , Imagem Multimodal , Placa Aterosclerótica/sangue , Estudos Prospectivos , Rosuvastatina Cálcica/uso terapêutico , Tomografia de Coerência Óptica , TranscriptomaRESUMO
Consistent evidence supports the pro-atherogenic properties of dietary trans-fatty acids (TFAs). However, there are no clinical data on TFA intake and atheroma plaque. We cross sectionally investigated whether the proportion of total C18:1 TFA in red blood cells (RBCs), which mirrors dietary TFA intake, independently relates to carotid plaque prevalence in subjects with new-onset type 2 diabetes mellitus without prior cardiovascular disease (n=101, 56% men, mean age 61 years) and age- and sex-matched controls (n=96). RBC fatty acid composition was determined by gas chromatography. Plaque (defined as carotid intima-media thickness ≥1.5 mm) was sonographically assessed at three bilateral carotid segments. In multivariate models adjusting for group (diabetes or control) and classical cardiovascular risk factors, for each 0.1% increase in RBC total C18:1 TFA isomers, plaque prevalence increased by 53% (P=.002). In contrast, for each 0.1% increase in RBC alpha-linolenic acid, the vegetable omega-3 fatty acid, plaque prevalence decreased by 43% (P<.001). We conclude that the RBC membrane proportion of total C18:1 TFA, considered a proxy of intake, directly relates to the ultrasound feature that best predicts future cardiovascular events. Our findings support current recommendations to limit TFA intake for cardiovascular health promotion.
Assuntos
Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/sangue , Gorduras Insaturadas na Dieta/efeitos adversos , Membrana Eritrocítica/metabolismo , Ácidos Oleicos/sangue , Placa Aterosclerótica/complicações , Ácidos Graxos trans/sangue , Idoso , Biomarcadores/sangue , Artérias Carótidas/diagnóstico por imagem , Espessura Intima-Media Carotídea , Estudos Transversais , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/etiologia , Angiopatias Diabéticas/prevenção & controle , Gorduras Insaturadas na Dieta/uso terapêutico , Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Ômega-3/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ácidos Oleicos/efeitos adversos , Placa Aterosclerótica/sangue , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/epidemiologia , Prevalência , Estudos Prospectivos , Fatores de Risco , Espanha/epidemiologia , Ácidos Graxos trans/efeitos adversos , Ultrassonografia Doppler em CoresRESUMO
BACKGROUND: Atherosclerosis is a chronic immune-inflammatory disorder and one of the leading causes responsible for cardiovascular morbidity and mortality. Traditional Chinese medicine treatment with multi-targets has shown prospects for the therapeutic effect on atherosclerosis. Thus, this study aims to investigate whether xiaoxianggou has benefit for reducing the atherosclerotic plaque area in endogenous high Ang II ApoE(-/-) mice and investigated the underlying mechanisms. METHODS: Endogenous high Ang II ApoE(-/-) mice model was generated by using two kidney one clip (2K1C). All mice were treated by intragastric administration with xiaoxianggou two times a week for 16 weeks. En face plaque area was analyzed by oil-red O staining. Serum anti-OxLDL antibodies were measured by ELISA assay. Expression of miR-203 and Ets-2 were evaluated using qRT-RCR and western blotting analysis, respectively. RESULTS: This study revealed that xiaoxianggou treatment dose-dependently reduced the atherosclerotic plaque area and serum autoantibodies against oxLDL, elevated miR-203 expression and reduced Ets-2 expression in endogenous high Ang II ApoE(-/-) mice. In primary arterial ECs, Xiaoxianggou reverses the reduced miR-203 expression and the elevated Ets-2 expression induced by AngII, which was further recovered by miR-203 inhibitor. Additionally, miR-203 regulated the expression of Ets-2 by targeting Ets-2-3' UTR. Moreover, miR-203 inhibitor reversed the reduction of atherosclerotic lesion area induced by Xiaoxianggou. CONCLUSIONS: These findings present that xiaoxianggou plays an anti-atherosclerotic role in endogenous high Ang II ApoE(-/-) mice model, which is partly due to its antioxidant actions against atherosclerosis and the inhibition of miR-203 on the expression of Ets-2 in endothelial cells.
Assuntos
Angiotensina II/metabolismo , Apolipoproteínas E/deficiência , Medicamentos de Ervas Chinesas/uso terapêutico , Células Endoteliais/metabolismo , MicroRNAs/metabolismo , Placa Aterosclerótica/tratamento farmacológico , Proteína Proto-Oncogênica c-ets-2/genética , Regiões 3' não Traduzidas/genética , Angiotensina II/farmacologia , Animais , Aorta/patologia , Apolipoproteínas E/metabolismo , Autoanticorpos/sangue , Medicamentos de Ervas Chinesas/farmacologia , Células Endoteliais/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Lipoproteínas LDL/imunologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , Placa Aterosclerótica/sangue , Placa Aterosclerótica/genética , Proteína Proto-Oncogênica c-ets-2/metabolismoRESUMO
BACKGROUND AND AIMS: Coronary computed tomography angiography (CCTA)-verified high risk plaque (HRP) characteristics including positive remodeling and low attenuation plaque have been associated with acute coronary syndromes. Several studies reported that the n-3 polyunsaturated fatty acids have been associated with cardiovascular events. However, the relationship between serum eicosapentaenoic acid to arachidonic acid (EPA/AA) ratio and CCTA-verified HRP in patients without known coronary artery disease (CAD) is unclear. We aimed at investigating the relation between EPA/AA and CCTA-verified HRP in patients without known CAD. METHODS: We included 193 patients undergoing CCTA without known CAD (65.5 ± 12.0 years, 55.0% male). No patient has been treated with EPA. The relation of coronary risk factors, lipid profile, high-sensitivity C-reactive protein, coronary artery calcification score (CACS), number of vessel disease, plaque burden, and EPA/AA with the presence of HRP was evaluated by logistic regression analysis. Incremental value of EPA/AA to predict HRP was also analyzed by C-index, NRI, and IDI. A Cox proportional hazards model was used to estimate the time to cardiovascular event. RESULTS: HRP was observed in 37 (19%) patients. Multivariable logistic regression analysis revealed that current smoking (OR 2.58; p=0.046), number of vessel disease (OR 1.87; p=0.031), and EPA/AA ratio (OR 0.65; p=0.0006) were independent associated factors of HRP on CCTA. Although the addition of EPA/AA to the baseline model did not significantly improve C-index, both NRI (0.60, p=0.0049) and IDI (0.054, p=0.0072) were significantly improved. Patients with HRP had significantly higher rate of events compared with patients without HRP (14% vs. 3%, Logrank p=0.0004). On multivariable Cox hazard analysis, baseline EPA/AA ratio was an independent predictor (HR 0.57, p=0.047). CONCLUSIONS: Low EPA/AA was an associated factor of HRP on CCTA in patients without CAD. In addition to conventional coronary risk factors and CACS, EPA/AA and CCTA might be useful for risk stratification of CAD.
Assuntos
Ácido Araquidônico/sangue , Doença da Artéria Coronariana/sangue , Ácido Eicosapentaenoico/sangue , Placa Aterosclerótica/sangue , Síndrome Coronariana Aguda/sangue , Idoso , Proteína C-Reativa/metabolismo , Ácidos Graxos Ômega-3/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Tomografia Computadorizada por Raios XRESUMO
SCOPE: To investigate the efficacy of lingonberries in prevention of atherosclerosis, using atherosclerosis-prone Apoe(-/-) mice and to clarify whether effects were associated with changes in the gut microbiota, gut metabolites, and lipid metabolism. METHODS AND RESULTS: Male Apoe(-/-) mice were fed either low-fat diet, high-fat diet, or high-fat diet with 44% lingonberries for 8 weeks. Blood lipid profiles, hepatic gene expression, atherosclerotic plaques in the aortic root region of the heart, bacterial 16S rRNA gene profiles, and cecal short-chain fatty acids (SCFAs) were analyzed. Triglyceride levels and amount of atherosclerotic plaques decreased in the group fed lingonberries in comparison to the high-fat group. Hepatic expression of the bile acid synthesis gene Cyp7a1 was significantly upregulated in the lingonberry group. Lingonberries increased the cecal relative abundance of bacterial genera Bacteroides, Parabacteroides and Clostridium. The cecal levels of total SCFAs were significantly lower in the lingonberry group, while the cecal proportion of propionic acid was higher in mice fed lingonberries. CONCLUSION: Intake of lingonberries resulted in decreased triglyceridemia and reduced atherosclerosis. The altered gut microbiota composition and SCFA profile was associated with increased hepatic bile acid gene expression in mice fed lingonberries.
Assuntos
Aterosclerose/prevenção & controle , Microbioma Gastrointestinal/efeitos dos fármacos , Preparações de Plantas/farmacologia , Vaccinium vitis-Idaea/química , Animais , Bacteroidetes/efeitos dos fármacos , Ceco/microbiologia , Colesterol/sangue , Colesterol 7-alfa-Hidroxilase/genética , Colesterol 7-alfa-Hidroxilase/metabolismo , Clostridium/efeitos dos fármacos , Dieta com Restrição de Gorduras , Dieta Hiperlipídica , Fibras na Dieta/administração & dosagem , Ácidos Graxos Voláteis/análise , Regulação da Expressão Gênica , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Knockout para ApoE , Tamanho do Órgão/efeitos dos fármacos , Placa Aterosclerótica/sangue , Placa Aterosclerótica/prevenção & controle , RNA Ribossômico 16S/isolamento & purificação , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Esteroide 12-alfa-Hidroxilase/genética , Esteroide 12-alfa-Hidroxilase/metabolismo , Triglicerídeos/sangueRESUMO
BACKGROUND: Aged garlic extract (AGE) has been shown to retard the progression of coronary calcification in patients with coronary artery disease. OBJECTIVE: To clarify the mechanism of AGE's action to retard atherosclerosis, we investigated whether AGE suppresses the formation and progression of atherosclerosis in Apolipoprotein E (Apoe)-knockout (ApoE-KO) mice. METHODS: Male C57BL/6J mice (control mice, 5 wk old) were fed a standard diet, whereas male ApoE-KO mice (5 wk old) were fed a standard diet with or without 3% AGE for 12 or 24 wk. After the treatment, blood samples, aortas, and spleens were collected from all mice. Concentrations of total cholesterol (TC), HDL cholesterol, and triglycerides (TGs) in serum were measured. The area of atherosclerotic lesion in the aorta was examined by Oil Red O staining. The relative abundances of monocytes plus macrophages (CD11b(+) cells) and interferon-γ-producing CD4(+) T cells in spleen were assessed by flow cytometric analysis. RESULTS: The atherosclerotic lesion areas in the aortas of ApoE-KO mice were 87 and 114 times as great (P < 0.01) as those in control mice at 12 and 24 wk, respectively. AGE feeding significantly inhibited the progression of atherosclerotic lesion area in ApoE-KO mice by 22% (P < 0.05) at 12 wk. In addition, serum concentrations of TC and TGs in ApoE-KO mice were significantly higher than those in control mice at 12 and 24 wk. Treatment with AGE significantly suppressed the increases in serum concentrations of TC and TGs in ApoE-KO mice by 21% (P < 0.05) and 19% (P < 0.05) at 24 wk, respectively, and reduced the relative abundance of CD11b(+) cells in ApoE-KO mice by 24% (P < 0.05) at 12 wk. CONCLUSION: These data suggest that the antiatherosclerotic activity of AGE is at least partly due to the suppression of inflammation and lipid deposition in the vessels during the early stage of atherosclerotic development in ApoE-KO mice.
Assuntos
Aterosclerose/prevenção & controle , Colesterol/sangue , Alho , Inflamação/prevenção & controle , Fitoterapia , Extratos Vegetais/uso terapêutico , Triglicerídeos/sangue , Animais , Aorta/patologia , Apolipoproteínas E/sangue , Aterosclerose/sangue , Aterosclerose/etiologia , Aterosclerose/patologia , Antígenos CD11/metabolismo , Progressão da Doença , Inflamação/sangue , Inflamação/imunologia , Mediadores da Inflamação/sangue , Interferon gama/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Extratos Vegetais/farmacologia , Placa Aterosclerótica/sangue , Placa Aterosclerótica/etiologia , Placa Aterosclerótica/prevenção & controle , Baço/efeitos dos fármacos , Linfócitos T/metabolismoRESUMO
Oxylipins are oxidation products of polyunsaturated fatty acids (PUFAs) that affect a broad range of physiological processes, including cell proliferation, inflammation, inflammation resolution, and vascular function. Moreover, oxylipins are readily detectable in plasma, and certain subsets of oxylipins have been detected in human atherosclerotic lesions. Taken together, we set out to produce a detailed quantitative assessment of plasma and plaque oxylipins in a widely used model of atherosclerosis, to identify potential biomarkers of disease progression. We administered regular chow or regular chow supplemented with 0.5% cholesterol (HC) to male New Zealand white rabbits for 12 weeks to induce hypercholesterolemia and atherosclerosis. Our targeted lipidomic analyses of oxylipins on plaques isolated from rabbits fed the HC diet detected 34 oxylipins, 28 of which were in compliance with our previously established quality control acceptance criteria. The arachidonic acid (AA) metabolite derived from the COX pathway, 6-keto-PGF1α was the most abundant plaque oxylipin, followed by the linoleic acid (LA) metabolites 9-HODE, 13-HODE and 9,12,13-TriHOME and the arachidonic acid (AA)-derivatives 11-HETE and 12-HETE. We additionally found that the most abundant oxylipins in plasma were three of the five most abundant oxylipins in plaque, namely 11-HETE, 13-HODE, and 9-HODE. The studies reported here make the first step towards a comprehensive characterization of oxylipins as potentially translatable biomarkers of atherosclerosis.
Assuntos
Hipercolesterolemia/sangue , Oxilipinas/sangue , Placa Aterosclerótica/sangue , Animais , Cromatografia Líquida de Alta Pressão , Ácidos Graxos Insaturados/metabolismo , Humanos , Hipercolesterolemia/metabolismo , Masculino , Espectrometria de Massas , Oxilipinas/metabolismo , Placa Aterosclerótica/metabolismo , CoelhosRESUMO
BACKGROUND: Fibroblast growth factor 23 (FGF23) is a phosphaturic hormone implicated in disorders of serum phosphorus concentration and vitamin D. The role of FGF23 in vascular calcification remains controversial. METHODS: Relationships between FGF23 and coronary artery calcified atherosclerotic plaque (CAC), aortoiliac calcified plaque (CP), carotid artery CP, volumetric bone mineral density (vBMD), albuminuria, and estimated glomerular filtration rate (eGFR) were determined in 545 African Americans with type 2 diabetes (T2D) and preserved kidney function in African American-Diabetes Heart Study participants. Generalized linear models were fitted to test associations between FGF23 and cardiovascular, bone, and renal phenotypes, and change in measurements over time, adjusting for age, gender, African ancestry proportion, body mass index, diabetes duration, hemoglobin A1c, blood pressure, renin-angiotensin-system inhibitors, statins, calcium supplements, serum calcium, and serum phosphate. RESULTS: The sample was 56.7% female with a mean (SD) age of 55.6 (9.6) years, diabetes duration of 10.3 (8.2) years, eGFR 90.9 (22.1) ml/min/1.73 m2, urine albumin:creatinine ratio (UACR) 151 (588) (median 13) mg/g, plasma FGF23 161 (157) RU/ml, and CAC 637 (1,179) mg. In fully adjusted models, FGF23 was negatively associated with eGFR (p < 0.0001) and positively associated with UACR (p < 0.0001) and CAC (p = 0.0006), but not with carotid CP or aortic CP. Baseline FGF23 concentration did not associate with changes in vBMD or CAC after a mean of 5.1 years follow-up. CONCLUSIONS: Plasma FGF23 concentrations were independently associated with subclinical coronary artery disease, albuminuria, and kidney function in the understudied African American population with T2D. Findings support relationships between FGF23 and vascular calcification, but not between FGF23 and bone mineral density, in African Americans lacking advanced nephropathy.
Assuntos
Diabetes Mellitus Tipo 2/sangue , Fatores de Crescimento de Fibroblastos/sangue , Placa Aterosclerótica/sangue , Adulto , Negro ou Afro-Americano , Idoso , Albuminúria/sangue , Albuminúria/complicações , Pressão Sanguínea , Densidade Óssea , Artérias Carótidas/fisiopatologia , Vasos Coronários/fisiopatologia , Estudos Transversais , Diabetes Mellitus Tipo 2/etnologia , Feminino , Fator de Crescimento de Fibroblastos 23 , Seguimentos , Taxa de Filtração Glomerular , Hemoglobinas Glicadas/análise , Humanos , Artéria Ilíaca/fisiopatologia , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Fosfatos/química , Placa Aterosclerótica/etnologia , Sistema Renina-Angiotensina , Fatores de Risco , Tomografia Computadorizada por Raios X , Vitamina D/sangueRESUMO
UNLABELLED: Supplementation with arginine in combination with atorvastatin is more efficient in reducing the size of an atherosclerotic plaque than treatment with a statin or arginine alone in homozygous Watanabe heritable hyperlipidemic (WHHL) rabbits. We evaluated the mechanism behind this feature by exploring the role of the arginine/asymmetric dimethylarginine (ADMA) ratio, which is the substrate and inhibitor of nitric oxide synthase (NOS) and thereby nitric oxide (NO), respectively. METHODS: Rabbits were fed either an arginine diet (group A, n = 9), standard rabbit chow plus atorvastatin (group S, n = 8), standard rabbit chow plus an arginine diet with atorvastatin (group SA, n = 8) or standard rabbit chow (group C, n = 9) as control. Blood was sampled and the aorta was harvested for topographic and histological analysis. Plasma levels of arginine, ADMA, cholesterol and nitric oxide were determined and the arginine/ADMA ratio was calculated. RESULTS: The decrease in ADMA levels over time was significantly correlated to fewer aortic lesions in the distal aorta and total aorta. The arginine/ADMA ratio was correlated to cholesterol levels and decrease in cholesterol levels over time in the SA group. A lower arginine/ADMA ratio was significantly correlated to lower NO levels in the S and C group. DISCUSSION: A balance between arginine and ADMA is an important indicator in the prevention of the development of atherosclerotic plaques.