[Reparative and therapeutic effect of rhBMP-2m on mice injured by chemotherapy].

Aim: To probe the therapeutic effect of recombinant human bone marrow morphogenetic protein-2 maturation peptide(rhBMP-2m) on mouse bone marrow injury caused by cyclophosphamide (CTX).

Methods: 18 mice were divided randomly into 3 groups, namely CTX injection group(CTX group), BMP therapy group(BMP group) and PBS control group(Control group), 6 mice each group. CTX of 200 mg/kg per mouse was intraperitonealy(IP) injected at a time to BMP group and CTX group so as to establish the experimental model of mouse bone marrow injury. In BMP group, the therapy started from the second day after injection of CTX by using IP injection of 0.5 mg BMP per mouse each day. In control group, PBS was injected only. Changes of peripheral blood leukocyte numbers in 3 groups were observed. On the 5th and 8th day after CTX injection, DNA content in mouse bone marrow karyocytes and variation of cell cycle were analysed by flow cytometry(FCM). Colony forming unit granulocyte-macrophage(CFU-GM) was cultivated simultaneously.

Results: On the 4th day after injection of CTX, the leukocyte number in mouse peripheral blood of CTX group dropped to the lowest level, and then picking up gradually. In respect to the variation of the leukocyte number, there was no significant difference between BMP group and CTX group (P>0.05). On the 5th day, the ratio of G(0)/G(1) phase cells in BMP group was notably higher than that of CTX group, and the necrotic and apoptotic rates decreased markedly (P<0.01). On the 8th day, the number of karyocytes in mouse bone marrow of BMP group was obviously more than that of CTX group (P<0.01).

Conclusion: BMP has some therapeutic effect on mouse bone marrow injury caused by CTX.