title: [Effect of silencing connective tissue growth factor on rat liver fibrosis and the accumulation of extracellular matrix].
abstract: OBJECTIVE
  To investigate the anti-fibrogenesis property of intraportal vein injection of small interfering RNA targeting connective tissue growth factor (CTGF) in a rat model of liver fibrosis and its effect on the accumulation of extracellular matrix (ECM).
  
  
  METHODS
  Thirty male rats were randomly divided into five groups. Some rats received CCl4 subcutaneously every three days for 6 consecutive weeks, and in the meantime they also received either siRNA targeting CTGF (preventive group), saline (model group) or siRNA (siRNA control group) by intraportal vein injections. Other rats received CCl4 by subcutaneous injection for 2 weeks, followed by CCl4 and CTGF siRNA intraportal vein injection for 4 more weeks (as treatment group). The expressions of CTGF and type I and III collagen genes were detected by means of reverse transcription-polymerase chain reaction (RT-PCR) and/or Western blot respectively. Hepatic histology was evaluated by HE and Sirius red stained sections. The collagen staining areas were measured quantitatively using a computer-aided manipulator with slight modifications. Serum procollagen type III and hyaluronic acid were determined by radioimmunoassay.
  
  
  RESULTS
  Six weeks after CCl4 injection, prominent upregulation of gene expressions of CTGF, type I and III collagen, and laminin in saline or siRNA-treated rat livers were observed. The expressions of CTGF at mRNA and protein level and type I and III collagen at mRNA level were markedly reduced in rats with CTGF siRNA treated for four or six weeks. Expressions of CTGF at mRNA and protein levels decreased by 76%+/-8%, 80%+/-3% (F = 68.630) and 95%+/-2%, 93%+/-3% (F = 21.234, P < 0.01); type I and III collagen and laminin at mRNA levels decreased by 74%+/-8%, 78%+/-8%, 31%+/-7% and 57%+/-6%, 59%+/-10%, 43%+/-9% (F = 24.219, 16.315, 9.716, P < 0.01) compared with rats in the model group at 72 h. The CTGF siRNA treatment markedly reduced serum levels of procollagen type III and hyaluronic acid and the degrees of liver fibrosis.
  
  
  CONCLUSIONS
  Intraportal vein siRNA injection targeting CTGF could significantly inhibit CTGF gene expression in rats, thereby attenuating liver fibrosis by reducing ECM accumulation.
authors: Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors: Guang-ming
authors: GM
authors: Li
authors: Ding-guo
authors: DG
authors: Li
authors: Qing
authors: Q
authors: Xie
authors: Yi
authors: Y
authors: Shi
authors: Shan
authors: S
authors: Jiang
authors: Hui-juan
authors: HJ
authors: Zhou
authors: Han-ming
authors: HM
authors: Lu
authors: You-xin
authors: YX
authors: Jin
mesh_terms: D000818:Animals; D002251:Carbon Tetrachloride; D055513:Connective Tissue Growth Factor / Q000378:metabolism*; D005109:Extracellular Matrix / Q000378:metabolism*; D020868:Gene Silencing; D008099:Liver / Q000378:metabolism / Q000473:pathology; D008106:Liver Cirrhosis, Experimental / Q000139:chemically induced / Q000378:metabolism / Q000473:pathology*; D008297:Male; D034741:RNA, Small Interfering; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: C526316:CCN2 protein, rat; D034741:RNA, Small Interfering; D055513:Connective Tissue Growth Factor; D002251:Carbon Tetrachloride