Objective To study the radioprotective effect of polypeptide from Chlamys farreri (PCF) on ultraviolet B(UVB)-irradiated murine thmocytes in vitro. Methods The murine thymocytes were exposed to UVB radiation. MTT method was used to detect the cell viability. The activities of intracellular glutathione peroxidase (GSH-Px), superoxided dismutase(SOD) and catalase (CAT) were measured. Intracellular reactive oxygen species (ROS) and the effect of PCF on UVB-induced apoptosis were investigated by flow cytometry. Results PCF could greatly enhance the viability of murine thymocyte and markedly promote the activities of GSH-Px, SOD and CAT, while the amount of ROS was decreased. PCF could inhibit UVB-induced thymocyte apoptosis. Conclusion PCF has significant radioprotective effects on UVB-irradiated murine thymocytes in vitro.

Objective To investigate the antioxidative effect of polypeptide from Chlamys farreri (PCF) on HaCaT cells damaged by ultraviolet B (UVB). Methods HaCaT cells model established by UVB irradiation were randomly divided into seven groups. After pretreatment with different concentrations of PCF for 1 h, the cells were irradiated by UVB at a dose of 30mJ/cm~ 2, and followed further incubatiou for 18 h. Enzyme activities including superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) were determined by biochemical methods. Total antioxidative capacity (T-AOC) and malondialdehyde (MDA) were also determined. Results PCF could enhance the activities of SOD, GSH-Px and CAT; increased T-AOC and inhibited MDA formation. Conclusion These results indicated that PCF exhibited protective effects on HaCaT cells irradiated by UVB owing to its antioxidative action.

Aim To study the infuences of Haishengsu extracted from Tegillarca granosa on cultured tumor cells of lung cancer, breast cancer and carcinoma of stomach from human in vitro and its preventive antitumor effect on transplanted tumor in mice in vivo. Methods The inhibitory effect of Haishengsu on tumor cells proliferation was assayed by MTT method, and transplant tumor models of sarcoma 180 (S 180), Ehrlich ascites carcinoma (EAC), and hepatoma (Heps) were used. Before and after transplantation, different doses of Haishengsu were given to the mice for 10 days. The inhibition rates and life span of the mice were calculated. Results Haishengsu at concentrations of 0.5%～2.0% inhibited the proliferation of tested tumor cells in vitro,especially on lung cancer cells with a dose dependent manner (r= 0.974,P