20-Hydroxyeicosatetraenoic acid inhibits the apoptotic responses in pulmonary artery smooth muscle cells.
20-Hydroxyeicosatetraenoic acid (20-HETE), a omega-hydroxylation product of arachidonic acid catalyzed by cytochrome P450 4A (CYP4A), plays a role in vascular smooth muscle remodeling. Although its effects on angiogenic responses are known, it remains unclear whether 20-HETE acts on apoptosis of pulmonary arterial smooth muscle cells (PASMC), an important step in PASMC remodeling, and what pathways are involved in the process. Here we show evidence for the missing information. The effect of 20-HETE on PASMC apoptosis and the apoptosis-associated signaling pathways were determined with cell viability assay, Annexin V and propidium idodide binding, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL), mitochondrial potentials assay, caspase activity assay and Western blots. We found that exogenous 20-HETE suppressed the serum deprivation-induced loss of bovine PASMCs and prevented Annexin V binding, DNA nick end labeling and chromatin condensation. The effect was worsened by 17-octadecynoic acid (17-ODYA), which inhibited the production of endogenous 20-HETE. Furthermore, 20-HETE induced the expression of bcl-2, maintained the stability of mitochondria membrane, and relieved the activation of caspase-9 and caspase-3. Such effects were reversed in the presence of 17-ODYA. Thus, these findings indicate that 20-HETE protects PASMCs against apoptosis by acting on, at least in part, the intrinsic apoptotic pathway.
Wang
Zhigang
Z
Department of Biopharmaceutical Sciences, College of Pharmacy, Harbin Medical University, 157 Baojian Road, Nangang District, Harbin, Heilongjiang 150081, PR China.
Tang
Xiaobo
X
Li
Yumei
Y
Leu
Changlian
C
Guo
Lei
L
Zheng
Xiaodong
X
Zhu
Daling
D
D017304:Annexin A5 / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects*; D001562:Benzimidazoles; D015153:Blotting, Western; D053148:Caspase 3 / Q000378:metabolism; D053453:Caspase 9 / Q000378:metabolism; D002843:Chromatin / Q000737:chemistry; D004396:Coloring Agents; D016895:Culture Media, Serum-Free; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology; D006893:Hydroxyeicosatetraenoic Acids / Q000494:pharmacology*; D020287:In Situ Nick-End Labeling; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008564:Membrane Potentials / Q000187:drug effects; D051336:Mitochondrial Membranes / Q000187:drug effects; D032389:Myocytes, Smooth Muscle / Q000187:drug effects*; D011419:Propidium; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D011651:Pulmonary Artery / Q000166:cytology* / Q000187:drug effects*; D013778:Tetrazolium Salts; D013844:Thiazoles
D017304:Annexin A5; D001562:Benzimidazoles; D002843:Chromatin; D004396:Coloring Agents; D016895:Culture Media, Serum-Free; D005231:Fatty Acids, Unsaturated; D006893:Hydroxyeicosatetraenoic Acids; D019253:Proto-Oncogene Proteins c-bcl-2; D013778:Tetrazolium Salts; D013844:Thiazoles; C047008:17-octadecynoic acid; D011419:Propidium; C055987:20-hydroxy-5,8,11,14-eicosatetraenoic acid; D007770:L-Lactate Dehydrogenase; D053148:Caspase 3; D053453:Caspase 9; C022616:thiazolyl blue; C017807:bisbenzimide ethoxide trihydrochloride