Metabolic responses to air-exposure stress of the Chinese mitten crab (Eriocheir sinensis) revealed by a combined analysis of metabolome and transcriptome

Air-exposure stress (AES) caused by aquacultural practices is detrimental to physiological fitness and can lower the survival rate of cultured animals. Previous studies showed that AES could induce the readjustment of energy utilization, respiration, antioxidant production, and immune activity. To further understand the AES coping mechanism of Chinese mitten crabs, we applied an integrated metabolomic and transcriptomic analysis to study the hepatic metabolic responses when crabs were exposed to air at room temperature for 30 h or at lower temperature for 97 h. The metabolomic analysis showed that AES caused an increase in five carbohydrate-metabolism related metabolites and five lipid-metabolism related metabolites. Correspondingly, the transcriptomic analysis revealed the changed expression of eight genes which were related to carbohydrate or lipid metabolism. In addition, our results showed that lowering temperature could alleviate the impacts of AES by depressing metabolic rates. Finally, our results demonstrated sexual dimorphism of lipid metabolism in Eriocheir sinensis.