ABSTRACT
Objective To investigate the roles of long noncoding RNA-myocardial infarction-associated transcript (MIAT) on lens epithelial cells (LECs) fibrosis induced by transforming growth factor-β2(TGF-β2).Methods LECs line (SRA01/04) was cultured in conventional DMEM (normal control group) and DMEM containing 10 ng/ml TGF-β2(TGF-β2 induced group) for 48 hours.The morphology of the cells was observed under the optical microscope,and the relative expression levels of M IAT,E-cadherin (E-cad),α-smooth muscle action (α-SMA),collagen Ⅰ (Coll Ⅰ) in protein level and mRNA level were detected by real-time fluorescence quantitative PCR and Western blot,respectively.The cells cultured in DMEM or DMEM containing 10 ng/ml TGF-β2 were transfected by siNRA empty carrier (siNRA group,siNRA+TGF-β2 group) and siRNA-MIAT (siRNA-MIAT group,siNRA-MIAT+ TGF-β2 group) for 48 hours,and the morphology of the cells was observed under the optical microscope,and the relative expression levels of MIAT,E-cadherin (E-cad),α-smooth muscle action (α-SMA),collagen Ⅰ (Coll Ⅰ) in protein level and mRNA level were detected by real-time fluorescence quantitative PCR and Western blot.Results The cells in the normal control group showed the round and polygon in shape,and those in the TGF-β2 induced group showed the spindle-like.Compared with the normal control group,the relative expression levels of MIAT mRNA,α-SMA mRNA and Coll Ⅰ mRNA were significantly elevated (2.497 ± 0.644 vs.0.827 ± 0.062;2.951 ±0.146 vs.1.085±0.517;2.115 ±0.090 vs.1.002 ± 0.088),and the expression of E-Cad mRNA was significantly reduced (0.102±0.027 vs.1.020±0.262) in the TGF-β2 induced group (P =0.045,0.004,0.000,0.025).The expressions of MIAT,α-SMA,Coll Ⅰ and E-Cad showed a similar trend between two groups.The relative expressions of MIAT protein and mRNA were evidently reduced in the SiRNA-MIAT group compared with the siRNA empty vector group (all at P＜0.05).Compared with the siRNA+TGF-β2 group,the relative expressions of α-SMA and Coll Ⅰ in protein and mRNA levels were significantly reduced,and the expressions of E-cad protwin and mRNA were elevated in the siRNA-MIAT+TGF-β2 group (all at P＜0.01).Conclusions MIAT might participate in TGF-β2-induced LECs-EMT.The down-regulation of MIAT in the LECs inhibits the fibrosis of LECs.