Effect of NADPH oxidase on Ang II-mediated apoptosis of H9C2 cardiomyocytes

HE Qian; CAI Chao; CHEN Zhen

doi:10.3969/j.issn.1674-4055.2016.09.23

Abstract：Objective To analyze the apoptosis of H9C2 cardiomyocytes induced by angiotensin II (Ang II) through NADPH oxidase/P38MAPK pathway.Methods H9C2 cardiomyocytes were cultured in vitro, and then divided into control group (added only nutrient fluid), Ang II group (added Ang II besides nutrient fluid), apocynin group (added apocynin besides nutrient fluid) and Ang II+apocynin group (added Ang II and apocynin besides nutrient fluid, eachn=6). The activity of NADPH oxidase was detected after 24 h, apoptosis was detected by using terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL), and expressions of P38MARK and relevant apoptotic protein were detected by using Western Blot method.Results The apoptotic rate was (12.20± 1.18)% in control group, (14.71±3.88)% in apocynin group, (62.33±4.79)% in Ang II group and (13.67±2.59)%in Ang II+apocynin group. Compared with control group, the apoptotic rate increased significantly in Ang II group, and compared with Ang II group it decreased in Ang II+apocynin group (allP<0.05). Compared with control group, the activity of NADPH oxidase decreased in apocynin group and increased significantly in Ang II group (P<0.05). The activity of NADPH oxidase decreased in Ang II+apocynin group compared with Ang II group (P<0.05). Compared with normal cells, the expressions of P38MAPK and apoptotic protein Bax increased, and expression of anti-apoptotic protein Bcl-2 decreased after Ang II effecting (allP<0.05). The expressions of P38MAPK and apoptotic protein Bax decreased, and expression of anti-apoptotic protein Bcl-2 increased in Ang II+apocynin group compared with Ang II group (allP<0.05).Conclusion The apoptosis of H9C2 cardiomyocytes is induced by Ang II through NADPH oxidase/P38MAPK pathway.