cyanidin-3-o-beta-glucopyranoside and Atherosclerosis

Endothelial cell (EC) dysfunction is a major symptom associated with the initiation of atherosclerosis (AS). Cyanidin-3-O-glucoside (C3G) has the potentials to attenuate AS symptoms. In the current study, the mechanism driving the effects of C3G on AS rabbits and injured ECs were explored by focusing on the changes in miR-204-5p/SIRT1 axis. AS symptoms were induced in rabbits using high-fatty diet (HFD) plus balloon catheter injured method and handled with C3G of two doses. Then the changes in artery wall structure, hemodynamics parameters, blood lipid level, systemic inflammation, and miR-204-5p/SIRT1 axis were detected. EC dysfunction was imitated by subjecting human umbilical vein endothelial cells (HUVECs) to TNF-α, which was then handled with C3G. The changes in apoptosis, inflammation, and miR-204-5p/SIRT1 axis were detected. The results showed that the administrations of C3G improved artery wall structure and hemodynamics parameters, decreased blood lipid levels, and suppressed pro-inflammatory cytokine production in HFD rabbits, which was associated with the down-regulation of miR-204-5p and the up-regulation of SIRT1. In in vitro assays, the treatments of C3G suppressed apoptosis, inhibited inflammation, down-regulated miR-204-5p level, and induced SIRT1 level in HUVECs. The overexpression of miR-204-5p impaired the protective effects of C3G on the injured HUVECs by increasing cell apoptosis and inflammation. The findings outlined in the current study confirmed the protective effects of C3G on EC function, which was associated with the down-regulation of miR-204-5p and the up-regulation of SIRT1.

Topics: Animals; Anthocyanins; Apoptosis; Atherosclerosis; Diet, High-Fat; Disease Models, Animal; Endothelial Cells; Human Umbilical Vein Endothelial Cells; Humans; Inflammation; MicroRNAs; Rabbits; Signal Transduction; Sirtuin 1

Blueberries are a rich source of anthocyanins (ACNs) and phenolic acids (PA), which are hypothesized to protect against development of atherosclerosis. The present study examined the effect of an ACN- and PA-rich fractions, obtained from a wild blueberry powder, on the capacity to counteract lipid accumulation in macrophages derived from monocytic THP-1 cells. In addition, we tested the capacity of pure ACNs and their metabolites to alter lipid accumulation.. THP-1-derived macrophages were incubated with fatty acids (500 μM oleic/palmitic acid, 2:1 ratio) and different concentrations (from 0.05 to 10 μg mL(-1)) of ACN- and PA-rich fractions, pure ACN standards (malvidin, delphinidin and cyanidin 3-glucoside), and metabolites (syringic, gallic and protocatechuic acids). Lipid accumulation was quantified with the fluorescent dye Nile red.. Lipid accumulation was reduced at all concentrations of the ACN-rich fraction tested with a maximum reduction at 10 μg mL(-1) (-27.4%; p < 0.0001). The PA-rich fraction significantly reduced the lipid accumulation only at the low concentrations from 0.05 µg mL(-1) to 0.3 µg mL(-1), with respect to the control with fatty acids. Supplementation with pure ACN compounds (malvidin and delphinidin-3-glucoside and its metabolic products (syringic and gallic acid)) reduced lipid accumulation especially at the low concentrations, while no significant effect was observed after cyanidin-3-glucoside and protocatechuic acid supplementation.. The results demonstrated a potential role of both the ACN- and PA-rich fractions and single compounds in the lipid accumulation also at concentrations close to that achievable in vivo.

Topics: Anthocyanins; Antioxidants; Atherosclerosis; Blueberry Plants; Carotenoids; Cell Line, Tumor; Cell Survival; Dietary Fiber; Dietary Sucrose; Fatty Acids; Gallic Acid; Glucosides; Humans; Hydroxybenzoates; Lipid Metabolism; Macrophages; Plant Extracts; Powders; Protective Agents; Trace Elements; Vitamins

Statins have often been used in atherosclerosis treatment because of its pleiotropic effects on inflammation. However, some adverse effects of high doses of statin show reverse effects after withdrawal. Cyanidin-3-glucoside (C3G) is a powerful anti-inflammation and antioxidant that has been of interest for use in combination with low doses of statin, which may be alternative treatment for atherosclerosis. The objective is to investigate the synergistic effect of atorvastatin and C3G in angiotensin II (Ang II)-induced inflammation in vascular smooth muscle cells. Human aortic smooth muscle cells (HASMCs) were exposed to Ang II with or without atorvastatin and C3G alone, or in combination. The results revealed that the combination of atorvastatin and C3G produces synergism against inflammation and oxidative stress. The mechanism of the combination of atorvastatin and C3G suppressed the translocation of the p65 subunit of NF-κB from cytosol to nucleus, and attenuated the expression of proteins including inducible nitric oxide synthase, intracellular adhesion molecule 1(ICAM-1), and vascular cell adhesion molecule 1(VCAM-1), in addition to nitric oxide (NO) production. Moreover, C3G exerts the antioxidative properties of atorvastatin through down-regulating NOX1 and promoting the activity of the Nrf2(-)ARE signaling pathway and downstream proteins including heme oxygenase (HO-1), NAD(P)H:quinoneoxidoreductase 1 (NQO-1), and glutamate-cysteine ligase catalytic subunit (γ-GCLC), besides increasing the activity of superoxide dismutase (SOD) enzymes. Taken together, these results suggest that a combination of low dose statins and C3G might serve as a potential regulator of the atherosclerosis process which is mediated by attenuating oxidative stress, thereby inhibiting NF-κB and activating Nrf2 signaling pathways induced by Ang II.

Topics: Angiotensin II; Anthocyanins; Anti-Inflammatory Agents; Atherosclerosis; Atorvastatin; Cell Proliferation; Cells, Cultured; Drug Evaluation, Preclinical; Drug Synergism; Enzyme Induction; Glucosides; Humans; Intercellular Adhesion Molecule-1; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; NF-kappa B; Nitric Oxide Synthase Type II; Oxidation-Reduction; Oxidative Stress; Reactive Oxygen Species; Signal Transduction; Vascular Cell Adhesion Molecule-1; Vasculitis

Atherosclerosis is accelerated in diabetes mellitus mainly due to the reduced availability and function of endothelial progenitor cells (EPCs). The purpose of this study was to determine the protective effects of the anthocyanin cyanidin-3-O-β-glucoside (C3G) on EPC function and endothelial repair in diabetic apolipoprotein E-deficient (apoE(-/-)) mice. Diabetes mellitus was induced in 8-wk-old male apoE(-/-) mice with streptozotocin. Diabetic apoE(-/-) mice were fed the AIN-93 diet or an AIN-93 diet supplemented with C3G (0.2% wt:wt) for 6 wk. Sham-injected apoE(-/-) mice fed the AIN-93 diet served as nondiabetic controls. The endothelium-dependent relaxation response to acetylcholine in the aortas of C3G-fed mice was greater by 51% compared with diabetic mice fed the AIN-93 diet (P < 0.05) and was similar to that in nondiabetic apoE(-/-) mice. The capacity of in vitro adhesion to fibronectin, migration, and tube formation was significantly impaired in diabetic EPCs (decreased by 83, 61.9, and 74.5%, respectively, compared with nondiabetic controls; all P < 0.01), which was significantly rescued in response to C3G (increased by 3.9-, 2-, and 1.8-fold compared with diabetic EPCs, respectively; all P < 0.05). At the molecular level, the phosphorylation levels of AMP-activated protein kinase (AMPK) Thr 172 and endothelial nitric oxide synthase (eNOS) Ser1177 were higher in EPCs derived from the C3G-treated diabetic mice compared with those in nondiabetic mice. Furthermore, compared with nondiabetic controls, diabetic apoE(-/-) mice had a 3.5-fold increase in the aortic lesion area, which was lowered by 45% in C3G-fed diabetic mice. This study extends our current knowledge that C3G improves the impairment of EPC function, enhances endothelial repair, and thus limits accelerated atherogenesis caused by diabetes. Our findings emphasize the potential utility of anthocyanin in the prevention and treatment of diabetic vascular complications.

Topics: Acetylcholine; AMP-Activated Protein Kinases; Animals; Anthocyanins; Aorta; Apolipoproteins E; Atherosclerosis; Diabetes Mellitus, Experimental; Diabetic Angiopathies; Diet; Dietary Supplements; Endothelial Cells; Endothelium; Glucosides; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Nitric Oxide Synthase Type III; Stem Cells; Streptozocin; Wound Healing

Although previous studies have shown that consumption of anthocyanin extract from plant foods reduces hypercholesterolemia and the severity of atherosclerosis in different animal models, the mechanisms of these actions remained unclear. This study investigated whether pure anthocyanin inhibit atherosclerosis development and reduce hypercholesterolemia in the apolipoprotein E (ApoE)-deficient mice through enhancement of fecal bile acid excretion, a critical pathway for eliminating circulation cholesterol from the body.. Five-week-old male ApoE-deficient mice were fed the AIN-93G diet supplemented with or without cyanidin-3-O-β-glucoside (0.06% w/w) for 12 weeks. Results showed that cyanidin-3-O-β-glucoside consumption inhibited the formation of aortic sinus plaque and reduced hypercholesterolemia, along with promoted fecal bile acid excretion and upregulated hepatic cholesterol 7a-hydroxylase expression (CYP7A1). In mouse primary hepatocytes, cyanidin-3-O-β-glucoside treatment increased bile acid synthesis and CYP7A1 expression in a liver X receptor alpha (LXRα)-)-dependent manner. Scintillation proximity and time-resolved fluorescence resonance energy transfer assays revealed that cyanidin-3-O-β-glucoside functions as an agonist of LXRα.. Our results indicate that the hypocholesterolemic activity of cyanidin-3-O-β-glucoside was, at least in part, mediated by activating the potential LXRα-CYP7A1-bile acid excretion pathway, thus contributing to the antiatherogenic effect of cyanidin-3-O-β-glucoside. Importantly, cyanidin-3-O-β-glucoside could activate LXRα in an agonist-dependent manner.

Topics: Animals; Anthocyanins; Apolipoproteins E; Atherosclerosis; Bile Acids and Salts; Cholesterol 7-alpha-Hydroxylase; Gene Knockdown Techniques; Glucosides; Hepatocytes; Hypercholesterolemia; Liver; Liver X Receptors; Male; Mice; Orphan Nuclear Receptors; Up-Regulation

In this study, we investigated the protective effects of the anthocyanin cyanidin-3-O-β-glucoside (C3G) on hypercholesterolemia-induced endothelial dysfunction in apoE-deficient (apoE(-/-)) mice. In the prevention study, twenty 8-wk-old male apoE(-/-) mice (n = 10/group) were fed a high-fat, cholesterol-rich diet (HCD) or the HCD supplemented with C3G (2 g/kg diet) for 8 wk. The endothelium-dependent relaxation response to acetylcholine in the aortas of the C3G-fed mice was greater compared with those fed the HCD (P < 0.05). The atherosclerotic plaque area in the aortic sinus of mice fed the C3G diet was lowered by 54% compared with those fed the HCD (P < 0.01). Mice fed C3G had greater expression of the ATP-binding cassette transporter G1 (ABCG1) and lower cholesterol, mainly 7-ketocholesterol (7-KC), concentrations than those fed the HCD. Superoxide production and lipid hydroperoxides in aorta were lower in mice fed C3G compared with those fed the HCD. The phosphorylation levels at Ser1177 of endothelial NO synthase (eNOS) and the production of cyclic GMP (cGMP) in aorta were greater in C3G-fed mice than in HCD-fed mice. In the therapy study, apoE(-/-) mice were fed the HCD for 8 wk and then continued to receive the HCD or were switched to the HCD supplemented with C3G (2 g/kg diet) for another 8 wk. The established endothelial dysfunction and atherosclerosis were reversed, accompanied by greater ABCG1 expression in aorta, lower cholesterol and 7-KC concentrations, and greater generation of cGMP in mice fed C3G compared with those fed the HCD. Taken together, our results show that the anthocyanin C3G prevents or reverses hypercholesterolemia-induced endothelial dysfunction by inhibiting cholesterol and 7-oxysterol accumulation in the aorta and the subsequent decrease in superoxide production, thereby preserving eNOS activity and NO bioavailability.

Topics: Animals; Anthocyanins; Aorta; Apolipoproteins E; Atherosclerosis; Dietary Fats; Dietary Supplements; Endothelium, Vascular; Glucosides; Hypercholesterolemia; Hypolipidemic Agents; Male; Mice; Mice, Knockout; Nitric Oxide; Oxidative Stress

We and others have demonstrated that anthocyanins have antiatherogenic capability. Because intact anthocyanins are absorbed very poorly, the low level of circulating parent anthocyanins may not fully account for their beneficial effect. We found recently that protocatechuic acid (PCA), a metabolite of cyanidin-3 to 0-β-glucoside (Cy-3-G), has a remarkable antiatherogenic effect.. To investigate whether mouse gut microbiota metabolizes Cy-3-G into PCA and to determine whether and how PCA contributes to the antiatherogenic potency of its precursor, Cy-3-G.. PCA was determined as a gut microbiota metabolite of Cy-3-G in ApoE(-/-) mice, verified by the utilization of antibiotics to eliminate gut microbiota and further microbiota acquisition. PCA but not Cy-3-G at physiologically reachable concentrations promoted cholesterol efflux from macrophages and macrophage ABCA1 and ABCG1 expression. By conducting a miRNA microarray screening, we revealed that expression of miRNA-10b in macrophages can be reduced by PCA. Functional analyses demonstrated that miRNA-10b directly represses ABCA1 and ABCG1 and negatively regulates cholesterol efflux from murine- and human-derived macrophages. Further in vitro and ex vivo analyses verified that PCA accelerates macrophage cholesterol efflux, correlating with the regulation of miRNA-10b-ABCA1/ABCG1 cascade, whereas Cy-3-G consumption promoted macrophage RCT and regressed atherosclerotic lesion in a gut microbiotaendependent manner.. PCA, as the gut microbiota metabolite of Cy-3-G, exerts the antiatherogenic effect partially through this newly defined miRNA-10b-ABCA1/ABCG1-cholesterol efflux signaling cascade. Thus, gut microbiota is a potential novel target for atherosclerosis prevention and treatment.

Topics: Animals; Anthocyanins; Apolipoproteins E; Atherosclerosis; ATP Binding Cassette Transporter 1; ATP Binding Cassette Transporter, Subfamily G, Member 1; ATP-Binding Cassette Transporters; Biological Transport; Cells, Cultured; Cholesterol; Glucosides; HEK293 Cells; Humans; Hydroxybenzoates; Intestinal Absorption; Intestines; Lipoproteins; Macrophages, Peritoneal; Metagenome; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; MicroRNAs

Topics: Animals; Anthocyanins; Atherosclerosis; Cholesterol; Glucosides; Humans; Metagenome; MicroRNAs