Influence of connective tissue growth factor antisense oligonucleotide on angiotensin Ⅱ-induced epithelial mesenchymal transition in HK2 cells

摘要

Aim: The present study was designed to further investigate the effect of connective tissue growth factor antisense oligonucleotide (CTGF-AS) on angiotensin Ⅱ (Ang Ⅱ)-induced tubular cell epithelial mesenchymal transition (EMT) in vitro. Methods: The human proximal tubular cell line (HK2) was grown in Dulbecco's modified Eagle's medium containing 10% heat inactivated fetal calf serum. After being rested in serum-free medium for 24 h, the influence of CTGF-AS (20 μg/mL) on Ang Ⅱ-induced (1×10-7 mol/L) CTGF mRNA and the protein expression were examined by using reverse transcription-polymerase chain reaction and indirectimmunofluorescence. The effect of CTGF-AS on Ang Ⅱ-induced cellular ultrastructure was observed using a transmissive electronic microscope. The expression of α-smooth action (α-SMA) was assayed by immunocytochemistry. In all experiments, the control group was treated with scrambled oligonucleotide. Results: It was shown that Ang Ⅱ significantly induced the increasing expression of CTGF mRNA and protein (P＜0.01, respectively), which were significantly abolished by treatment with CTGF-AS. After stimulating cells with Ang Ⅱ, the cellular ultrastructure showed mesenchymal features. These effects were partially inhibited by CTGF-AS. Ang Ⅱ significantly resulted in the expression of α-SMA in time dependent manner, which was markedly attenuated by the treatment with CTGF-AS (P＜0.01, respectively). In contrast, no similar effects were observed in the control group treated with scrambled oligonucleotide. Conclusion: Ang Ⅱ-induced EMT in human proximal tubular epithelial cells (PTC) can be attenuated by treatment with CTGF-AS. Our data provides further evidence that CTGF might be involved in Ang Ⅱ-induced EMT in PTC.