Pachymic acid protects H9c2 cardiomyocytes from lipopolysaccharide-induced inflammation and apoptosis by inhibiting the extracellular signal-regulated kinase 1/2 and p38 pathways

Pachymic acid (PA), a lanostane-type triterpenoid and the major component of Poria cocos alcoholic extracts, has various pharmacological effects, including anti-inflamma-tory, anti-oxidative and anti-apoptotic. However, few studies have investigated the effects of PA on lipopolysaccharide (LPS) -induced H9c2 cell apoptosis and inflammation, or identified the possible mechanisms underlying these effects. In the present study, H9c2 cardiomyocytes were stimulated by LPS and treated with or without PA. The increased mRNA expression levels of tumor necrosis factor-a, interleukin (IL)-1 and IL-6 induced by LPS were attenuated following treatment with PA. PA also attenuated LPS-induced apoptosis, as determined by a terminal deoxynucleotidyl transferase dUTP nick end labeling assay, and regulated the LPS-induced protein expression levels of caspase 3, 8 and 9. Furthermore, the phosphorylations of extracellular-regulated kinase (Erk) 1/2 and p38 in the LPS-treated H9c2 cells were inhibited by PA. These results suggested that treatment with PA prevented the LPS-induced inflammatory and apoptotic response in cardiomyocytes, which may be mediated by inhibition of the Erk1/2 and p38 pathways.