Ketamine enhances autophagy and endoplasmic reticulum stress in rats and SV-HUC-1 cells via activating IRE1-TRAF2-ASK1-JNK pathway

Background Ketamine-related cystitis (KC) has been researched in many clinical studies, but its exact mechanism is ambiguous and needs further research. Methods We established a KC rat model and analyzed physiological, biochemical, and urodynamic parameters of ketamine (KET)-related bladder injury. Bladder histologic feature, reactive oxygen species (ROS), autophagy-, apoptosis-, and endoplasmic reticulum stress (ERS)-related markers were examined by hematoxylin and eosin staining, Masson staining, ROS kit, quantitative real-time polymerase chain reaction, and western blot. In vitro, effects of 0.01, 0.1, and 1 mM KET on cell vitality, apoptosis, ROS level, autophagy-, apoptosis-, and ERS-related markers were examined again. Effects of KET-1 and salubrinal on complex formation, autophagy-, apoptosis-, and ERS-related markers were examined by Co-Immunoprecipitation and western blot. After transfection with shIRE1, complex formation, cell biological behaviors, ROS level, autophagy-, apoptosis-, and ERS-related markers were examined again. Results KET induced bladder hyperactivity and injury. KET facilitated urinary frequency, ROS production, and induced bladder histologic injury by activating autophagy-, apoptosis-, and ERS-related markers in rats. In vitro, KET (0.01, 0.1, and 1 mM) restrained cell vitality and elevated apoptosis and ROS level via activating autophagy-, apoptosis-, and ERS-related markers. Moreover, salubrinal reversed the promotion of KET-1 on complex formation, autophagy-, apoptosis-, and ERS-related marker expressions. After transfection with shIRE1, shIRE1 weakened complex formation induced by KET-1, and the effects of KET-1 on cells were offset by shIRE1. Conclusion KET enhanced autophagy and ERS in vivo and in vitro via restraining IRE1-TRAF2-ASK1-JNK pathway.