YAP表达抑制对髁突软骨干细胞增殖和凋亡的影响

Effects of YAP Inhibition on Proliferation and Apoptosis of Fibrocartilage Stem Cells

目的:探究YAP表达抑制对髁突软骨干细胞(FCSC)增殖和凋亡的影响,为深入理解颞下颌骨关节炎(TMJOA)病理机制提供线索。方法:分离鉴定大鼠FCSC,利用小干扰RNA(siRNA)体外转染FCSC抑制YAP表达,利用CCK-8法、流式细胞分析分别检测YAP表达抑制对FCSC增殖、细胞周期及凋亡率的影响。建立大鼠TMJOA模型,关节腔注射YAP抑制剂维替泊芬或不做处理,利用免疫荧光共染检测TMJOA下YAP表达抑制对FCSC数量的影响。结果:抑制YAP表达后CCK-8检测结果显示FCSC增殖活性显著抑制(P<0.05);细胞周期检测结果显示FCSC在G0/G1期比例增多(P<0.05),S期比例减少(P<0.05);凋亡检测结果显示FCSC凋亡率显著增加(P<0.05)。免疫荧光染色显示TMJOA下髁突软骨FCSC数量减少,且YAP抑制组比疾病对照组减少更显著,干细胞池损耗进一步加重。结论:YAP表达抑制可导致FCSC增殖活性降低,细胞周期改变,凋亡加剧,由此加重的干细胞池损耗可能是TMJOA病变不断进展的重要原因。

Objective:To investigate the effects of YAP inhibition on the proliferation and apoptosis of fibrocartilage stem cells(FCSCs),and bring new insights for pathology of TMJOA.Methods:FCSCs were isolated from SD rats and identified.Synthesized sequences of siRNA were transfected into FCSCs in vitro for YAP inhibition.The proliferation activity of FCSCs after transfection was detected by using cell counting kit-8(CCK-8).Changes in the cell cycle and apoptosis rate of FCSCs were detected by using flow cytometry.TMJOA model was conducted in rats,and verteporfin(a YAP inhibitor)was intra-articular injected,whose effect on the number of FCSC was detected by immunofluorescent costaining and compared with TMJOA control group.Results:After transfection,FCSC's proliferation activity was significantly inhibited(P<0.05)and apoptosis rate was increased(P<0.05).The cell cycle was changed as the proportion of G0/G1 increased(P<0.05)and S phase decreased(P<0.05).Immunofluorescent staining demonstrated that FCSC were decreased during TMJOA,which was intensified in the YAP inhibition group and resulted in a more depleted FCSC pool.Conclusion:The inhibition of YAP expression can decrease the proliferation activity,induce the apoptosis,and change the cell cycle of FCSCs.The consequent intensified FCSC pool depletion may be a critical reason for the progression of TMJOA.