Abstract: Objective　To study the protective effect of carnosine on H9C2 cardiomyocyte induced by high glucose and its mechanism.　Methods　High glucose culture medium containing 50 mmol/L glucose was used to establish a high glucose injury model, 5 and 15 mmol/L carnosine was given to protect H9C2 cells. MTT assay was used to detect the viability of H9C2 cells in each group. ELISA was used to determine the concentration of IL-1β, IL-6 and TNF-α inflammatory factors in culture medium. SOD, MDA, AST and LDH activities in cells were detected by kit. Active oxygen content in cells was determined by ethidium dihydrochloride. The expression of bax, bcl-2, p65 and IκB-α protein in cells was determined by Western-blot.　Results　Carnosine pretreatment could significantly increase cell viability, intracellular reactive oxygen species content decreased, SOD activity increased, AST and LDH activity decreased, MDA content decreased. Inflammatory factors in culture medium decreased significantly, p65 protein level in nucleus significantly decreased, and IκB-α protein level in cytoplasm increased，the expression of bax, the ratio of bax to bcl-2 increased and the differences was dose-dependent.　Conclusions　Carnosine can alleviate the injury of H9C2 myocardial cells induced by high glucose and reduce the inflammatory reaction of cells. Its mechanism may be related to ROS/NF-κB signaling pathway.

Key words:  , Carnosine, 　H9C2 cardiomyocyte, 　High glucose, 　Oxidative stress, 　Inflammation