Lu Wang,Wanyue Sang,Yi Jian,Yafan Han,Feifei Wang,Subinuer Wubulikasimu,Li Yang,Baopeng Tang,Yaodong Li
Objectives To investigate the role and mechanism of MAPK14/AIFM2 pathway in Ang II-induced atrial fibrillation in rats. Methods A rat model of AF was established for in vivo experiments and HL-1 cells were treated with Ang II to develop an in vitro model. In addition, HL1 cells overexpressing AIFM2 (oeAIFM2) were constructed. SB203580 was used to inhibit the expression of MAPK14. The role of MAPK14 in Ang II-AF model was investigated by in vivo electrophysiological examination and molecular biology tests. The role of MAPK14 / AIFM2 pathway on AF induced by Ang II was explored in vitro. Results MAPK14 and AIFM2 were significantly up-regulated in AF induced by Ang II (all P < 0.05). In vivo experiments indicated that inhibition of MAPK14 down-regulated AIFM2, improved atrial electrical conduction, AF inducibility and durations, and alleviated the structural and functional damage of heart and mitochondria (all P < 0.05). Both in vivo and in vitro tests showed that the MAPK14/AIFM2 pathway prevented Ang II-induced AF via regulating mitophagy-dependent apoptosis. Conclusions Inhibition of the MAPK14/AIFM2 pathway improved Ang II-induced AF by inhibiting mitophagy-dependent apoptosis.
Yueyue Li,Hongmei Xu,Zifeng Ma,Qiao Li,Yan Xiong,Xianrong Xiong,Jian Li,Daoliang Lan,Wei Fu
Apoptosis-inducing factor mitochondrion-associated 2 (AIFM2) has been identified as a gene with anti-ferroptosis properties. To explore whether AIFM2 exerts anti-ferroptosis role in yaks (Bos grunniens), we cloned yak AIFM2 gene and analyzed its biological characteristics. The coding region of AIFM2 had 1122 bp and encoded 373 amino acids, which was conserved in mammals. Next, RT-qPCR results showed an extensive expression of AIMF2 in yak tissues. Furthermore, we isolated yak skin fibroblasts (YSFs) and established a bisphenol A (BPA)-induced ferroptosis model to further investigate the role of AIFM2. BPA elevated oxidative stress (reactive oxygen species, ROS) and lipid peroxidation (malondialdehyde, MDA and BODIPY), and reduced cell viability and antioxidant capacity (glutathione, GSH), with the severity depending on the dosage. Of note, a supplement of Ferrostatin-1 (Fer), an inhibitor of ferroptosis, restored the previously mentioned indicators. Subsequently, we constructed an AIFM2 overexpression vector and designed AIFM2 specific interfering siRNAs, which were transfected into YSFs. The results showed that overexpressing AIFM2 alleviated ferroptosis, characterizing by significant changes of cell viability, ROS, BODIPY, MDA and GSH. Meanwhile, interfering AIFM2 aggravated ferroptosis, demonstrating the critical anti-ferroptosis role of the yak AIFM2 gene. This study shed light on further exploring the molecular mechanism of AIFM2 in plateau adaptability.