Effect of thymosin β4 on transforming growth factor-β/connective tissue growth factor of renal tubular interstitial fibrosis rats

Objective To investigate the influence of thymosin beta 4 (Tβ4) with two different dosages on the expression of transforming growth factor beta (TGF-β) and connective tissue growth factor (CTGF) in rats with renal tubular interstitial fibrosis, and to further estimate the changes of renal tubular interstitial lesions. Methods Rat models of renal tubular interstitial fibrosis were established by unilateral ureteral occlusion (UUO). The male SD rats were randomly divided into 4 groups and 15 rats in each group: sham group, model group, treatment group with 1 mg/L Tβ4 and treatment group with 5 mg/L Tβ4. Rats in sham group and model group were poured into the same amount of saline. The renal function and renal pathological changes were observed after the second week. The mRNA and protein expression of TGF-β and CTGF in renal tissues was tested by in-situ hybridization and Western blotting. Results Compared with that in sham group, the expression of TGF-β mRNA and its protein, CTGF mRNA and its protein was significantly higher in model group (all P 0.05). Conclusions Tβ4 treatment can inhibit the renal TGF-β and CTGF expression of rats with tubular interstitial fibrosis in a dose-dependent manner, and play a protective role in kidney. Key words: Thymosin; Transforming growth factor beta; Extracellular matrix proteins; Fibrosis