ISSN:
1524-475X
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Previous studies in a pig model of skin wound healing showed a coordinate expression of transforming growth factor-β (TGF-β) and connective tissue growth factor (CTGF), and exposure of porcine skin fibroblasts in vitro to recombinant human CTGF significantly up-regulated mRNA levels for a number of molecules. Therefore, based on recent reports that small interfering RNA (siRNA; double-stranded RNA) can effect silencing of the expression of gene(s), this approach has now been used with CTGF-specific siRNA to better understand the function of this growth factor in regulating matrix homeostasis and repair. Normal skin fibroblasts from Yorkshire pigs were treated with 0.1–0.8 µM CTGF siRNA, TGF-β, or TGF-β plus CTGF siRNA for 12–48 hours. Total RNA was isolated and quantified, and then mRNA levels for specific molecules were analyzed by reverse transcription-polymerase chain reaction. Protein levels for CTGF and HSP47 were assessed by Western-blot analysis. CTGF siRNA transfection led to significant decreases in mRNA and protein levels for CTGF in both a dose- and time-dependent manner. mRNA levels for types I and III procollagen, decorin, HSP47, tissue inhibitor of metalloproteinase -1, -2, -3, and basic fibroblast growth factor were also significantly and uniquely decreased following exposure of cells to CTGF siRNA. Addition of TGF-β to the cells led to increases in CTGF mRNA levels that were blocked by CTGF siRNA. CTGF siRNA exposure also significantly and selectively down-regulated TGF-β–mediated increases in mRNA levels for types I and III procollagen. The results indicate that CTGF can regulate extracellular matrix molecule, growth factor, and proteinase inhibitor gene expression, and that some of the TGF-β effects on skin fibroblasts are via a CTGF-dependent pathway. (WOUND REP REG 2004;12:–)
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1067-1927.2004.012113.x
