组织型转谷氨酰胺酶抑制剂对TGF-β_2诱导人LECs表达纤维连接蛋白和Ⅳ型胶原的影响

Effect of tTG inhibitor on the expression of FN and Col-Ⅳ induced by TGF-β_2 in human lens epithelial cells

目的观察组织型转谷氨酰胺酶(tTG)特异性抑制剂(MDC)对TGF-β2诱导人晶状体上皮细胞(LECs)表达纤维连接蛋白(FN)、Ⅳ型胶原(Col-Ⅳ)的影响。方法将含10%胎牛血清的DMEM培养基中培养的LECs株HLE-B3传代后分为5组:无血清培养基培养的HLE-B3为正常对照组;加入10μg/L TGF-β2处理的HLE-B3为TGF-β2组;10μg/L TGF-β2与100、200、400μmol/L MDC共同处理的HLE-B3为不同浓度MDC组。用半定量RT-PCR检测tTG、FN、Col-Ⅳ在HLE-B3中的表达,计算A(tTG/β-actin)、A(FN/β-actin)、A(Col-Ⅳ/β-actin)值。结果正常体外培养的HLE-B3中可表达一定量的tTG、FN及Col-Ⅳ。与正常对照组相比,10μg/L TGF-β2组中tTG、FN、Col-Ⅳ的表达明显增加(t=33.95,P<0.01;t=38.24,P<0.01;t=13.48,P<0.01);与TGF-β2组相比,100、200、400μmol/L MDC组中FN和Col-Ⅳ的表达明显减少(P<0.01)。100、200、400μmol/L MDC组各组间FN和Col-Ⅳ的表达差异均有统计学意义(P<0.01)。结论MDC可剂量依赖性地抑制TGF-β2诱导的LECs中FN、Col-Ⅳ表达的增加。tTG可促进人LECs表达FN、Col-Ⅳ,并参与后囊膜混浊(PCO)的形成。

Background Our previous research and other reports disclosed that the expression of tissue transglutaminase （tTG）in lens epithelial cells （LECs） of patients with cataract is enhanced, indicating tTG is related to formation of posterior capsule opaeification （PCO）. Objective Present study is to observe the effect of tTG specific inhibitor monodansyicadaverineon（MDC） on the expression of fibronectin（FN） and collagen 1V （Col-Ⅳ） induced by TGF-β2 in human LECs. Methods HLE-B3 was cultured in vitro in DMEM containing 10% fetal bovine serum and then were divided into 5 groups. The free-serum culture was used as normal control group. Free-serum cuhure containing 10 p.g/L TGF-β： was utilized as treatment group. 10 μg/L TGF-132 plused 100 μmol/L,200 μmol/L and 400 μmol/L MDC respectively in different concentrations as MDC- treatment group. Semiquantitative RT-PCR was used to assay the expression of tTG, FN and Col-Ⅳ in HLE-B3. A （tTG/β-actin） , A（tTN/β-actin） and A（Col-Ⅳ/β-actin） was calculated separately as the detecting indexes. Results tTG,FN and Col-IV were positively expressed in cultured HLE-B3. The expression levels of tTG,FN and Col-Ⅳ in HLE-B3 were remarkably increased in ttle group with 10 μg/L TGF-β2 conlpared with normal control group （ t = 33.95, P 〈 0.01 ; t = 38.24, P 〈 0. 01 ; t = 13.48, P 〈 0. 01 ）. The expression levels of FN and Col-Ⅳ were gradually declined in 100,200 and 400 0mol/L MDC groups in comparison with TGF-β2 treatment（P 〈 0. O1 ）. The significant differences were also found in the expressions of FN and Col-Ⅳ in HLE-B3 among 100,200 and 400 μmol/L MDC groups （ P 〈 0. 01 ）. Conclusion MDC inhibits the expression of FN and Col-iV induced by TGF-β2 in human LECs at a concentration-dependent manner, tTG may be involved in the formation of posterior capsule opacification through up-regulating the expressions of FN and Col-IV in human LECs.