scholarly journals GW29-e0256 Puerarin attenuates oxidized LDL-induced macrophage foam cell formation via PPARα signaling pathway

2018 ◽  
Vol 72 (16) ◽  
pp. C79
Author(s):  
Chun Sun ◽  
Jiaju Shang ◽  
Yangxue Wang ◽  
Qing Gao
Biomolecules ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 715
Author(s):  
Jae-Yong Kim ◽  
Soonok Kim ◽  
Sang Hee Shim

An endophytic fungus, Neofusicoccum parvum JS-0968, was isolated from a plant, Vitex rotundifolia. The chemical investigation of its cultures led to the isolation of a secondary metabolite, (3R)-5-hydroxymellein. It has been reported to have antifungal, antibacterial, and antioxidant activity, but there have been no previous reports on the effects of (3R)-5-hydroxymellein on atherosclerosis. The oxidation of lipoproteins and foam cell formation have been known to be significant in the development of atherosclerosis. Therefore, we investigated the inhibitory effects of (3R)-5-hydroxymellein on atherosclerosis through low-density lipoprotein (LDL) and high-density lipoprotein (HDL) oxidation and macrophage foam cell formation. LDL and HDL oxidation were determined by measuring the production of conjugated dienes and malondialdehyde, the amount of hyperchromicity and carbonyl content, conformational changes, and anti-LDL oxidation. In addition, the inhibition of foam cell formation was measured by Oil red O staining. As a result, (3R)-5-hydroxymellein suppressed the oxidation of LDL and HDL through the inhibition of lipid peroxidation, the decrease of negative charges, the reduction of hyperchromicity and carbonyl contents, and the prevention of apolipoprotein A-I (ApoA-I) aggregation and apoB-100 fragmentation. Furthermore, (3R)-5-hydroxymellein significantly reduced foam cell formation induced by oxidized LDL (oxLDL). Taken together, our data show that (3R)-5-hydroxymellein could be a potential preventive agent for atherosclerosis via obvious anti-LDL and HDL oxidation and the inhibition of foam cell formation.


2020 ◽  
Vol 61 (3) ◽  
pp. 351-364 ◽  
Author(s):  
Amit Kumar ◽  
Priya Gupta ◽  
Minakshi Rana ◽  
Tulika Chandra ◽  
Madhu Dikshit ◽  
...  

Pyruvate kinase M2 (PKM2) links metabolic and inflammatory dysfunction in atherosclerotic coronary artery disease; however, its role in oxidized LDL (Ox-LDL)-induced macrophage foam cell formation and inflammation is unknown and therefore was studied. In recombinant mouse granulocyte-macrophage colony-stimulating factor-differentiated murine bone marrow-derived macrophages, early (1–6 h) Ox-LDL treatment induced PKM2 tyrosine 105 phosphorylation and promotes its nuclear localization. PKM2 regulates aerobic glycolysis and inflammation because PKM2 shRNA or Shikonin abrogated Ox-LDL-induced hypoxia-inducible factor-1α target genes lactate dehydrogenase, glucose transporter member 1, interleukin 1β (IL-1β) mRNA expression, lactate, and secretory IL-1β production. PKM2 inhibition significantly increased Ox-LDL-induced ABCA1 and ABCG1 protein expression and NBD-cholesterol efflux to apoA1 and HDL. PKM2 shRNA significantly inhibited Ox-LDL-induced CD36, FASN protein expression, DiI-Ox-LDL binding and uptake, and cellular total cholesterol, free cholesterol, and cholesteryl ester content. Therefore, PKM2 regulates lipid uptake and efflux. DASA-58, a PKM2 activator, downregulated LXR-α, ABCA1, and ABCG1, and augmented FASN and CD36 protein expression. Peritoneal macrophages showed similar results. Ox-LDL induced PKM2- SREBP-1 interaction and FASN expression in a PKM2-dependent manner. Therefore, this study suggests a role for PKM2 in Ox-LDL-induced aerobic glycolysis, inflammation, and macrophage foam cell formation.


2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Huan Tao ◽  
Patricia G Yancey ◽  
John L Blakemore ◽  
Youmin Zhang ◽  
Lei Ding ◽  
...  

Background: Autophagy modulates vascular cell lipid metabolism, lipid droplet turnover, foam cell formation, cell survival and death, and inflammation. Scavenger receptor class B type I (SR-BI) deficiency causes impaired lysosome function in macrophages and erythrocytes. Methods and Results: Bone marrow transplantation studies were performed in ApoE and LDLR deficient mice to examine the effects of hematopoietic SR-BI deletion on atherosclerotic lesion autophagy. In addition, in vitro studies compared WT versus SR-BI -/- macrophages. Under conditions of cholesterol induced stress, the mRNA and protein levels of critical autophagy players including ATG5, ATG6/Belcin-1, ATG7 and LC3II were decreased by 37.8% to 84.6% (P<0.05 to 0.01) in SR-B1 -/- macrophages and atherosclerotic aortic tissue compared to controls. Electron microscopic analysis showed that SR-BI -/- versus WT macrophages had 80% fewer (P<0.05) autophagsomes in response to cholesterol enrichment. Macrophage SR-BI deficiency led to 1.8-fold (P<0.05) more lipid deposition and 2.5-fold more (P<0.01) apoptosis in response to oxidized LDL. Furthermore, hematopoietic SR-BI deletion caused 2.3 fold (P<0.05) more cell death in aortic atherosclerotic lesions compared to the WT control. Pharmacologic activation of autophagy did not reduce the levels of lipid droplets or cell apoptosis in SR-BI null macrophages vs WT control. WT peritoneal macrophages were used to examine SR-BI subcellular distribution and its interaction with VPS34/Beclin-1. In response to induction of autophagy, macrophage SR-BI was expressed in lysosomes and co-localized with LC3-II. Furthermore, we found that SR-BI directly interacted with the VPS34/Beclin-1 complex. Conclusions: SR-BI deficiency leads to defective autophagy and accelerates macrophage foam cell formation and apoptosis in experimental mouse atherosclerotic lesions. Macrophage SR-BI regulates expression of critical autophagy players and directly modulates autophagy via the VPS34/Beclin-1 pathway, identifying novel targets for the treatment of atherosclerosis.


2012 ◽  
Vol 32 (suppl_1) ◽  
Author(s):  
Yiliang Chen ◽  
David Kennedy ◽  
Zhichuan Li ◽  
Zijian Xie ◽  
Roy L Silverstein

Atherosclerosis, the leading cause of death in the developed countries, is characterized by macrophage foam cell formation. We previously showed that CD36, a scavenger receptor highly expressed in macrophages, mediates oxidized-LDL uptake, contributes to intracellular cholesterol accumulation and foam cell formation, and regulates macrophage migration and pro-inflammatory signaling. Consistently, cd36 deletion in mice protects from diet-induced atherosclerosis. Mechanistically, we discovered a novel signaling pathway, in which oxidized LDL (oxLDL) binding to CD36 activates Lyn kinase and initiates a cascade that is necessary for the pro-atherogenic cellular phenotype. How CD36 regulates Lyn kinase remains undefined. Since we previously showed that the Na/K-ATPase (NKA) regulates Src family kinases, including Lyn, we hypothesized that CD36 regulates Lyn kinase via an interaction with NKA. We used co-immunoprecipitation, FRET, and a novel cross linking assay to demonstrate that CD36 physically associates with NKA on the macrophage surface. Using a Lyn kinase activity assay, we showed that the interaction regulates Lyn kinase activity in response to oxLDL in macrophages. Moreover, a newly developed peptide inhibitor specifically blocked Lyn activation in response to oxLDL and attenuated oxLDL-stimulated cholesterol uptake (135.6±3.4 μM cholesterol/mg protein after 24 hours vs 173.8±7.7 μM cholesterol/mg protein in vehicle treated cells; p=0.0005; n=6). Taken together, we conclude that CD36 signals through NKA to regulate Lyn kinase activity in macrophages, which may be a molecular mechanism underlying cholesterol overloading and foam cell formation.


2021 ◽  
Vol 41 (3) ◽  
pp. 1076-1091
Author(s):  
Imam Manggalya Adhikara ◽  
Keiko Yagi ◽  
Dyah Samti Mayasari ◽  
Yoko Suzuki ◽  
Koji Ikeda ◽  
...  

Objective: Chondroitin sulfate proteoglycans are the primary constituents of the macrophage glycosaminoglycan and extracellular microenvironment. To examine their potential role in atherogenesis, we investigated the biological importance of one of the chondroitin sulfate glycosaminoglycan biosynthesis gene, ChGn-2 (chondroitin sulfate N -acetylgalactosaminyltransferase-2), in macrophage foam cell formation. Approach and Results: ChGn-2-deficient mice showed decreased and shortened glycosaminoglycans. ChGn-2 −/− /LDLr −/− (low-density lipoprotein receptor) mice generated less atherosclerotic plaque after being fed with Western diet despite exhibiting a metabolic phenotype similar to that of the ChGn-2 +/+ /LDLr −/− littermates. We demonstrated that in macrophages, ChGn-2 expression was upregulated in the presence of oxLDL (oxidized LDL), and glycosaminoglycan was substantially increased. Foam cell formation was significantly altered by ChGn-2 in both mouse peritoneal macrophages and the RAW264.7 macrophage cell line. Mechanistically, ChGn-2 enhanced oxLDL binding on the cell surface, and as a consequence, CD36—an important macrophage membrane scavenger receptor—was differentially regulated. Conclusions: ChGn-2 alteration on macrophages conceivably influences LDL accumulation and subsequently accelerates plaque formation. These results collectively suggest that ChGn-2 is a novel therapeutic target amenable to clinical translation in the future. Graphic Abstract: A graphic abstract is available for this article.


2014 ◽  
Vol 52 ◽  
pp. 24-30 ◽  
Author(s):  
Xi Cheng ◽  
Da-Li Zhang ◽  
Xiao-Bing Li ◽  
Jian-Tao Ye ◽  
Lei Shi ◽  
...  

2020 ◽  
Vol Volume 14 ◽  
pp. 3929-3940
Author(s):  
Haoran Wang ◽  
Yue Li ◽  
Xiaoliang Zhang ◽  
Zhonglin Xu ◽  
Jianzhong Zhou ◽  
...  

2017 ◽  
Vol 110 ◽  
pp. 142-150 ◽  
Author(s):  
Rishov Goswami ◽  
Michael Merth ◽  
Shweta Sharma ◽  
Mazen O. Alharbi ◽  
Helim Aranda-Espinoza ◽  
...  

2013 ◽  
Vol 305 (4) ◽  
pp. H563-H574 ◽  
Author(s):  
Ming-Sheng Zhou ◽  
Kiranmai Chadipiralla ◽  
Armando J. Mendez ◽  
Edgar A. Jaimes ◽  
Roy L. Silverstein ◽  
...  

Cigarette smoking is a major risk factor for atherosclerosis and cardiovascular disease. CD36 mediates oxidized LDL (oxLDL) uptake and contributes to macrophage foam cell formation. We investigated a role for the CD36 pathway in nicotine-induced activation of macrophages and foam cell formation in vitro and in vivo. Nicotine in the same plasma concentration range found in smokers increased the CD36+/CD14+ cell population in human peripheral blood mononuclear cells, increased CD36 expression of human THP1 macrophages, and increased macrophage production of reactive oxygen species, PKCδ phosphorylation, and peroxisome proliferator-activated receptor-γ (PPARγ) expression. Nicotine-induced CD36 expression was suppressed by antioxidants and by specific PKCδ and PPARγ inhibitors, implicating mechanistic roles for these intermediates. Nicotine synergized with oxLDL to increase macrophage expression of CD36 and cytokines TNF-α, monocyte chemoattractant protein-1, IL-6, and CXCL9, all of which were prevented by CD36 small interfering (si)RNA. Incubation with oxLDL (50 μg/ml) for 72 h resulted in lipid deposition in macrophages and foam cell formation. Preincubation with nicotine further increased oxLDL-induced lipid accumulation and foam cell formation, which was also prevented by CD36 siRNA. Treatment of apoE−/− mice with nicotine markedly exacerbated inflammatory monocyte levels and atherosclerotic plaque accumulation, effects that were not seen in CD36−/− apoE−/− mice. Our results show that physiological levels of nicotine increase CD36 expression in macrophages, a pathway that may account at least in part for the known proinflammatory and proatherogenic properties of nicotine. These results identify such enhanced CD36 expression as a novel nicotine-mediated pathway that may constitute an independent risk factor for atherosclerosis in smokers. The results also suggest that exacerbated atherogenesis by this pathway may be an adverse side effect of extended use of high concentrations of nicotine independent of their mode of administration.


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