Myricetin attenuated LPS induced cardiac injury in vivo and in vitro.

Sepsis induced myocardial dysfunction (SIMD) is a common complication and leads to an increased mortality. SIMD is closely related to inflammation and oxidative stress. Myricetin exhibits strong capacities of anti-inflammation and anti-oxidative stress, but its pharmacological effects for lipopolysaccharide (LPS) induced cardiac injury remains undefined. This study aimed to explore whether myricetin was efficient to alleviate SIMD in mice and neonatal rat cardiomyocytes injury. Mice administrated with myricetin (100 mg/kg, po, bid) or vehicle groups were challenged with LPS (10 mg/kg, ip), and cardiac functions examined by echocardiography after 12 hr LPS exposure. LPS markedly impaired mouse cardiac functions, which were significantly attenuated by myricetin administration. Myricetin significantly reduced the production of inflammatory cytokines both in serum and cardiac tissue. Myricetin could inhibit the nuclear translocation of p65, degradation of IκBα, and cellular apoptosis in vivo and in vitro. Myricetin also prevented overexpression of iNOS and reduction of oxidoreductase (SOD and GPx) activity. Besides, Myricetin treatment could attenuate production of inflammatory cytokines of peritoneal macrophages stimulated with LPS in vitro. Thus we concluded that myricetin could attenuate the LPS induced cardiac inflammation injury in vivo and in vitro. Myricetin may be a potential therapy or adjuvant therapy for SIMD.