Radioprotective effect of rhTPO on mice and MO7e cells

Abstract

Abstract: AIM: To study the therapeutic action of homemade rhTPO on thrombocytopenia of irradiated C57 mice and the effect of homemade rhTPO on apoptosis of MO7e cells induced by irradiation. METHODS: The male C57mice underwent total body irradiation(TBI) with a single 4 Gy dose using a 137Cs γ-rays source, and the blood samples were taken at different time points pre- and post-irradiation by cutting tails, and the platelet counts were determined.MTT assay was used to measure the rate of irradiated MO7e cells.The apoptosis of MO7e cells was observed with flow cytometer and E.M.microscopy. RESULTS: RhTPO (4.5-18μg/kg) dose-dependently rose the circulating platelet counts of C57 mice reduced by irradiation and its effect was more powerful and faster than that of rhIL-11.In vitro, rhTPO 10 and 100 μg/L obviously increased the viability rate of MO7e cells and reduced the apoptosis rate of MO7e cells upon irradiation. CONCLUSION: The homemade rhTPO has the capability of reducing the damage of hematopoietic system in irradiated mice, decreasing the apoptosis rate of MO7e cells upon irradiation and increasing the viability rate of MO7e cells.rhTPO has significant protective effect on mice and MO7e cells against irradiation injury.

Key words: recombinant human thrombopoietin, thrombocytopenia, radioprotection, apoptosis

CLC Number:

SU Ying-jie, LI Jing, YAO Ming-hui, GONG Qin-yan. Radioprotective effect of rhTPO on mice and MO7e cells[J]. Chinese Journal of Clinical Pharmacology and Therapeutics, 2007, 12(1): 66-71.

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