摘要
目的 探讨转化生长因子 (TGF) β1对人胚腱细胞增殖和代谢及其下游信号分子Smad的影响。方法 采用3 H 胸腺嘧啶脱氧核苷和3 H 脯氨酸掺入法观察TGF β1对人胚腱细胞的DNA和胶原合成的影响。采用半定量反转录聚 合酶链反应 (RT PCR)检测TGF β1作用 2 4h肌腱细胞Smad2、3和 7mRNA表达水平的变化。结果 在体积分数为 0 .5 %胎牛血清条件下TGF β1可刺激腱细胞增殖 ,其作用在 0 .5～ 10 .0 μg/L之间呈剂量依赖性增强 ( P <0 .0 5 ) ,饱和剂量 10μg/L增加DNA合成 73%。TGF β1各剂量组对胶原蛋白合成均有促进作用 (P <0 .0 5 ) ,最大效应剂量为 5 μg/L( 10 7% )。TGF β1能显著下调Smad2和Smad3基因的表达水平 ,同时诱导TGF β1信号拮抗因子Smad7的产生。结论 TGF β1能有效促进腱细胞增殖及胶原合成 ,同时能对其细胞内信号分子Smad的表达起自身调控作用。
Objective To investigate the effects of transforming growth factor β1 on proliferation, collagen synthesis and endogenous Smads expression of human tenocytes.Methods After synchronization, medium were replaced by F12 medium containing 0.5% FBS with TGF β 1 at different concentrations (0.5, 1.0, 5.0, 10.0, 20.0 μg/L). DNA synthesis elicited by TGF β 1 was measured by thymidine incoporation. proline incoporation method was used for synthesis of collagen. The levels of Smads mRNA induced by TGF β 1 were detected by semi quantitative reverse transcription polymerase chain reaction (RT PCR).Results There was a dose effect relationship between TGF β 1 concentration and tenocyte proliferation with a dosage range between 0.5 10.0?μg/L(P<0.05).Tenocytes responded to TGF β 1 doses of 10?μg/L by increased DNA synthesis by 73%. For collagen synthesis, TGF β 1 at 5?μg/L was found to most significantly promote proline incoporation (107%), despite TGF β 1 at different concentrations could all stimulate collagen synthesis(P<0.05). The levels of Smad2 and Smad3 mRNA were profoundly down regulated by TGF β 1, whereas expression of antagonistic Smad7 was obviously induced.Conclusion TGF β 1 could effectively promote the proliferation of tenocytes and expression of collagens in tenocytes, exert potent effects on endogenous Smad expression.
出处
《中华实验外科杂志》
CAS
CSCD
北大核心
2001年第5期461-463,共3页
Chinese Journal of Experimental Surgery
基金
国家自然科学基金资助项目(39830 390 )
