Apoptosis in response to heat stress is positively associated with Hsp90 expression in chicken myocardial cells in vitro
Xiao-Hui Zhang1, Hong Wu1, Shu Tang1, Qiao-Ning Li1, Jiao Xu1, Miao Zhang2, Ya-Nan Su1, Bin Yin1, Qi-Ling Zhao1, Nicole Kemper3, Joerg Hartung3, En-Dong Bao1,*
1College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
2College of Animal Science and Technology, Jinling Institute of Technology, Nanjing 210038, China
3Institute for Animal Hygiene, Animal Welfare and Farm Animal Behaviour, University of Veterinary Medicine Hannover, Foundation, Hannover 30173, Germany
Correspondence to: Tel: +86-2584395316; Fax: +86-2584398669; E-mail: b_endong@njau.edu.cn
Received: February 23, 2016; Revised: March 24, 2016; Accepted: May 12, 2016; Published online: June 13, 2016.
To determine whether Hsp90 expression is connected with cellular apoptotic response to heat stress and its mechanism, chicken (Gallus gallus) primary myocardial cells were treated with the Hsp90 promoter, aspirin, and its inhibitor, geldanamycin (GA), before heat stress. Cellular viability, heat-stressed apoptosis and reactive oxygen species (ROS) level under different treatments were measured, and key proteins expressions of the signaling pathway related to Hsp90 and their colocalization with Hsp90 were detected. The results showed that aspirin treatment increased the expression of Akt, STAT-3 and p-IKKα/β and the colocalization of Akt and STAT-3 with Hsp90 during heat stress, accompanied by improved viability and low apoptosis. GA inhibited significantly Akt expression and p-IKKα/β level, but not the STAT-3 quantity, while the colocalization of Akt and STAT-3 with Hsp90 was weakened, followed by lower cell viability and higher apoptosis. Aspirin after GA treatment partially improved the stress response and apoptosis rate of tested cells, caused by the recovery of Akt expression and colocalization, rather than the level of STAT-3 (including its co-localization with Hsp90) and p-IKKα/β. Therefore, Hsp90 expression has a positive effect on cellular capacity to resist heat-stressed injury and apoptosis. Meanwhile, inhibition of Hsp90 before stress partially attenuated its positive effects.
Keywords: Hsp90, anti-apoptosis, chicken primary myocardial cells, heat stress

© 2016 The Korean Society of Veterinary Science.