Effect Of Combination Methotrxate And Cyclophosphamide Intermitently Therapy On Cell Cycle And Apoptosis Of Lymphocyte In Wistar Rats

Background & ObjectivesRheumatoid arthritis(RA)has similar character to tumor.The pathogenesy correlate with abnormity of cell cycle and apoptosis of synoviocyte and lymphocyte.In the clinical practice, we united methotrexate(MTX)and cyclophosphamide(CTX)to treat RA by theory of tumor combined chemotherapy.The retrospective analysis had displayed the united program was significant in curative effect and the side effect was small.To explore MTX and CTX if they have the synergistic effect through detecting the effect of MTX and CTX on cell cycle and apoptosis of the peripheral blood lymphocyte(PBL)in rat.To clarity the program if affecting cell cycle by CyclinD1 through detecting the level of CyclinD1 in PBL and spleen.Furthermore, to evaluate its possible mechanisms and provide scientific basis for the clinic medication.Methods1.Wistar rats was allocated randomly to 4 groups.Normal control,minidose MTX group, minidose CTX group and the united of MTX and CTX group.2.The cell cycle,apoptosis ratio and the level of CyclinD1 of PBL was detected by FCM after given drugs 3 weeks,9 weeks,18 weeks and 27 weeks.3.The level of CyclinD1 in spleen was detected by immunohistochemistry after given drugs 27 weeks when the rats was dissected.Results1.Minidose MTX caused the rate of G0/G1 cells of PBL higher the normal control and the rate of S cells of PBL lower the normal control(P＜0.05).Minidose CTX was no obviously effect to cell cycle.Compared with Minidose MTX group,the rate of G0/G1 cells was decreasd and the rate of S cells was increased obviously(P＜0.05)when the two drugs were used unitedly. The two drugs appeared antagonistic effect to the rate of G0/G1 cells and S cells.The influence of the taking blood time to cell cycle was no statistical significance.2.The two drugs used united which caused apoptosis ratio significant higher than they were used alone(P＜0.05).They appeared synergistic effect to apoptosis ratio of PBL(P＜0.05). The influence of the taking blood time to apoptosis ratio was no statistical significance.3.The effect of different medication groups to the level of CyclinD1 in PBL and spleen was no statistical significance.The influence of the taking blood time to the level of CyclinD1 was no statistical significance. 4.There was obviously inverse correlation between the level of CyclinD1 and the rate of G0/G1 cells in PBL.There also was obviously inverse correlation between the level of CyclinD1 in spleen and the rate of G0/G1 cells in PBL.Conclusions1.The main effect of minidose MTX to PBL of rat is inhibiting proliferation to cell cycle. And it also could induce apoptosis.2.Minidose CTX is no obviously effect to cell cycle of PBL of rat.Its main effect is induce apoptosis.3.MTX caused the rate of G0/G1 cells of PBL of rat increased obviously.So the united use of MTX and CTX could injury the G0/G1 cells more effectively.Thereby educe synergistic effect by inducing apoptosis more effectively.4.The united project educe effect to cell cycle of PBL of normal rat probably no depend on the level of CyclinD1.