title: Beneficial effects of astragaloside IV against angiotensin II-induced mitochondrial dysfunction in rat vascular smooth muscle cells.
abstract: Angiotensin II (Ang II)-induced mitochondrial dysfunction is a prominent characteristic of the majority of cardiovascular diseases. Astragaloside IV (As-IV), the major active ingredient of Astragalus membranaceus (Fisch.) Bge. (a traditional Chinese herbal medicine), possesses antioxidant properties. The present study was carried out to examine whether As-IV can reverse Ang II-induced mitochondrial dysfunction in vascular smooth muscle cells (VSMCs) and to elucidate the underlying molecular mechanisms. Cultured rat aortic VSMCs treated with Ang II (1 µM) for 24 h exhibited mitochondrial dysfunction, including a decrease in mitochondrial oxygen consumption rates (OCRs), adenosine triphosphate (ATP) production and mitochondrial DNA (mtDNA) levels, as well as the disruption of mitochondrial structural integrity. Following treatment with Ang II, As-IV (50 µg/ml) was added to the culture medium followed by incubation for a further 24 h. The administration of As-IV significantly increased the mitochondrial OCRs, ATP production and the mtDNA levels, and reversed the mitochondrial morphological changes which occurred in the VSMCs. Treatment with As-IV also reversed the Ang II-induced increase in the production of reactive oxygen species (ROS), the increase in NADPH oxidase and xanthine oxidase activity, as well as the decrease in mitochondrial membrane potential (ΔΨm) and manganese superoxide dismutase (Mn-SOD) activity. Furthermore, treatment with As-IV led to an increase in the mRNA expression of peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α) and mitochondrial transcription factor A (Tfam), and in the protein expression of PGC-1α, parkin and dynamin 1-like protein 1 (Drp1) in the VSMCs. These results indicate that As-IV exerts beneficial effects on Ang II-induced mitochondrial dysfunction in rat VSMCs and that these effects are mediated through the inhibition of ROS overproduction, as well as the promotion of mitochondrial autophagy and mitochondrial biogenesis. These data demonstrate the antioxidant properties of As-IV.
authors.affiliation: Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Su
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Hengfang
authors.initials: H
authors.lastname: Wu
authors.affiliation: Research Institute of Cardiovascular Disease, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Bian
authors.affiliation: Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Jindan
authors.initials: J
authors.lastname: Xu
authors.affiliation: Research Institute of Cardiovascular Disease, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Chunrong
authors.initials: C
authors.lastname: Gu
authors.affiliation: Research Institute of Cardiovascular Disease, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Xiangjian
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Di
authors.initials: D
authors.lastname: Yang
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000804:Angiotensin II / Q000009:adverse effects*; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D002478:Cells, Cultured; D004272:DNA, Mitochondrial / Q000378:metabolism; D008297:Male; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D028361:Mitochondrial Diseases / Q000139:chemically induced* / Q000188:drug therapy* / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000378:metabolism; D032389:Myocytes, Smooth Muscle / Q000187:drug effects* / Q000378:metabolism; D019255:NADPH Oxidases / Q000378:metabolism; D010084:Oxidation-Reduction / Q000187:drug effects; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism; D012503:Saponins / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects; D014157:Transcription Factors / Q000378:metabolism; D014315:Triterpenes / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D004272:DNA, Mitochondrial; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; C501429:Ppargc1a protein, rat; D017382:Reactive Oxygen Species; D012503:Saponins; D014157:Transcription Factors; D014315:Triterpenes; D000804:Angiotensin II; C052064:astragaloside A; D000255:Adenosine Triphosphate; D019255:NADPH Oxidases