The Effect of Taurine on the Alkalinity Stress Resistance of Eriocheir sinensis.

High alkalinity, a major stress in saline-alkaline water, often leads to oxidative damage and apoptosis. Taurine has been shown to enhance the tolerance of aquatic animals to environmental stress, but whether it can reduce toxicity of alkalinity on Chinese mitten crab (Eriocheir sinensis) has not been determined. Thus, in this study, we investigated whether taurine could alleviate the deleterious effects of alkalinity stress on E. sinensis. The results revealed that taurine can improve the survival rate of the crab under 35.00 mmol/L alkalinity stress. Meanwhile, taurine inhibited the production of reactive oxygen species (ROS) and ameliorated the oxidative damage induced by alkalinity stress in crab. Taurine also inhibited alkalinity stress-mediated induction of mitogen-activated protein kinase-related pathways, subsequently suppressing the mRNA expression of Caspase 8 and Bax and preventing the occurrence of alkalinity stress-induced apoptosis in E. sinensis. In addition, inhibition of alkalinity stress-induced apoptosis by taurine may be related to the ability of taurine to bind to MAPK proteins. Overall, these results suggested that taurine can relieve the toxicity of high alkalinity on E. sinensis through mitigating oxidative damage and inhibiting apoptosis, supporting its applicability as a treatment for oxidative damage induced by high alkalinity.