Cardiovascular effects in vitro of a polysaccharide from Salvia miltiorrhiza

• SMP1 is a polysaccharide isolated from the roots of Salvia miltiorrhiza.
• SMP1 prevented H9c2 cells from hydrogen peroxide (H2O2)-induced apoptosis.
• SMP1 inactivated mitochondrial-mediated apoptosis in H2O2-treated H9c2 cells.
• SMP1 improved antioxidant defense capacity in H2O2-treated H9c2 cells.

A polysaccharide (SMP1) was isolated from the roots of Salvia miltiorrhiza. This study is designed to investigate whether SMP1 prevents H9c2 cells from hydrogen peroxide (H2O2)-induced apoptosis. The present study showed that exposure of H9c2 cells to 100 mM H2O2 for 24 h caused a significant increase in cell death and apoptosis, but pretreatment with SMP1 eliminated H2O2-induced apoptotic cell death. Furthermore, pretreatment with SMP1 significantly prevented the mitochondria disruption, cytochrome c release, the rise of the ratio between proapoptotic Bax and antiapoptotic Bcl-2 protein expression, and caspase-3 activation in H9c2 cells upon H2O2 stimulation. Moreover, the decline of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities together with the elevation of malondialdehyde (MDA) in PC12 cells exposed to H2O2 were remarkably reversed to normal levels by pretreatment with SMP1. These results suggest that SMP1 protects H9c2 cells from H2O2-induced apoptosis through inhibition of mitochondrial dysfunction, inactivation of caspase-3 cascade and enhancement of antioxidant capacity.