Effects of silencing TGF-β1 by RNAi on Smads signal transduction of rat renal allograft / 中华器官移植杂志

ABSTRACT

Objective To evaluate the effects of shRNA-TGF-β1 plasmid on Smads signal transduction of rat renal allograft.Methods A Sprague-Dawley to Wistar rat orthotopic transplant kidney-sclerosis accelerated model was constructed and transfected with short hairpin RNA-TGF-β1 based on the hydromechanics.The recipients were divided into three groupsgroup T(plasmid group)injected with shRNA-TGF-β1;group H(vacant plasmid group)injected with vacant plasmid;group Y(simply transplantation group)injected with no plasmid.In group J(sham-operated group)only right kidney was removed with no transplantation as control group.Transplanted kidneys and blood samples were collected at the first,second and third month after transplantation.The blood urea nitrogen(BUN)and serum Cr were tested by enzyme-linked immunoadsordent assay.The gene transcriptional level of TGF-β1 and Smad3/7 was detected by RT-PCR,and the protein variations of TGF-β1 and phosphorylated Smad3/7 were examined by Western blotting.Results At each test time point,the BUN and serum Cr were significantly higher in the plasmid group than in the sham-operated group(P<0.05 or P<0.01),but obviously lower than in the vacant plasmid group and simply transplantation group(P<0.05 or P<0.01).The expression of TGF-β1 as well as phosphorylated Smad3 was significantly higher in the plasmid group than in the sham-operated group(P<0.05 or P<0.01),but obviously lower than in the vacant plasmid group and simply transplantation group(P<0.05 or P<0.01).However,the expression of phosphorylated Smad7 was significantly lower in the plasmid group than in the sham-operated group(P<0.05 or P<0.01),but obviously higher than in the vacant plasmid group and simply transplantation group(P<0.05 or P<0.01).Conclusion Short hairpin RNA-TGF-β1 plasmid could significantly improve the renal function of rat renal allografts probably by downregulating phosphorylated Smad3 and upregulating phosphorylated Smad7,leading to the inhibition of TGF-beta 1 promoting fibrosis role and delay of the allograft fibrosis.