Ursolic Acid Ameliorates the Injury of H9c2 Cells Caused by Hypoxia and Reoxygenation Through Mediating CXCL2/NF-kappa B Pathway

Ursolic acid (UA) has been reported to possess several biological benefits, such as anti-cancer, anti-inflammation, antibacterial, and neuroprotective functions. This study detects the function and molecular mecha-nism of UA in H9c2 cells under hypoxia and reoxygenation (H/R) conditions. Under H/R stimulation, the effects of UA on H9c2 cells were examined using ELISA and western blot assays. The Comparative Toxicogenomics Database was employed to analyze the target molecule of UA. Small interfering RNA was used to knock down CXCL2 expression, further exploring the function of CXCL2 in H/R-induced H9c2 cells. The genes related to the nuclear factor-kappa B (NF--KB) pathway were assessed using western blot analysis. Significant effects of UA on H/R-induced H9c2 cell damage were observed, accompanied by reduced inflammation and oxidative stress injury. Additionally, the increased level of CXCL2 in H/R-induced H9c2 cells was reduced after UA stimulation. Moreover, CXCL2 knockdown strengthened the beneficial effect of UA on H/R-induced H9c2 cells. HY-18739, an activator of the NF-kappa B pathway, can increase CXCL2 expression. Moreover, the increased levels of p-P65 NF-kappa B and p-I-KB alpha in H/R-induced H9c2 cells were remarkably attenuated by UA treatment. In summary, the results indicated that UA may alleviate the damage of H9c2 cells by targeting the CXCL2/NF-kappa B pathway under H/R conditions.