转化生长因子-β2体外抑制人角膜内皮细胞增殖的作用

Inhibitory effect of transforming growth factor-β2 on the proliferation of human corneal endothelial cells in vitro

目的:研究转化生长因子TGF-β2对体外培养人角膜内皮细胞(HCEC)增殖的影响机制。方法:体外培养经血清饥饿法获得同步化的HCEC,用不同浓度TGF-β2对HCEC进行不同时间的处理,采用细胞计数、MTT染色以及流式细胞仪(FCM)和RealtimePCR检测TGF-β2对HCEC的增殖、细胞周期及细胞中p27kip1和p21cip1表达的影响。结果:TGF-β21～15μg/L对HCEC有显著的增殖抑制作用,具有浓度和时间依赖性,9μg/L是TGF-β2抑制HCEC细胞增殖的峰浓度。9μg/LTGF-β2处理后,处于G1/G0期HCEC数量显著增加,并具有时间依赖性。9μg/LTGF-β2处理24h后,p27kip1表达量显著增加,48h后p27kip1和p21cip1的表达量均显著增加,也具有时间依赖性。结论:TGF-β2对HCEC具有显著的浓度和时间依赖性增殖抑制作用,可能通过先后诱导p27kip1和p21cip1表达量的增加将细胞拘留在G1/G0期来实现的。

AIM： To investigate the ability of Thymosin β4 （Tβ4） to promote healing in an alkali injury model in vivo and the mechanisms involved in that process which Tβ4 may be a potential anti-inflammation agent in this model. METHODS： Corneas of the New-Zealand Rabbit were chemically burned with a 6mm disc soaked in 1mol/L NaOH for 30 seconds. Eyes were irrigated copiously with saline and then treated topically with PBS（Negative control group）, rh-EGF（jinyinshu drop, Positive control group）, and Tβ4 （0.1, 1, 10μg/50μL） twice daily. At the time point of 1 day, 3, 7, 14 days postburn, the healing rate of the cornea were examined and MMP-2, TIMP-2, VEGF immunostaining performed. RESULTS：Tβ4-treated corneas demonstrated improved cornea healing rate of 33.8% vs PBS-treated corneas of 22.8%（P〈0.01） , 1μg/50μL Tβ4 seemed to be the best dosage. Whereas immunohistochemistry result suggested that Tβ4 decreased corneal NF-κB expression（P〈0.01） after alkali injury, no change in IL（ interleukin） -1β was detected（P〉0.05）. The enzyme linked immunosorbent assay （ELISA） result suggested that theres a significant decrease to the NF-κB protein levels（P〈0.01）. CONCLUSION： Tβ4 treatment decreases corneal inflammation and inhibits the expression of NF-κB to improve cornea healing. The result have important clinical implications for the potential role of Tβ4 as a corneal anti-inflammatory agent. 