结缔组织生长因子在胰腺组织纤维化中的作用及机制探讨

目的 观察胰腺纤维化后结缔组织生长因子(Connective tissue growth factor,CTGF)在胰腺组织内的表达；进一步研究参与CTGF作用于胰腺星状细胞(pancreatic stellate cells,PSCs)的分子信号调控通路.方法 建立大鼠胰腺纤维化动物模型,HE染色、天狼猩红染色和免疫组织化学染色等方法观察胰腺纤维化后PSCs的活化情况及CTGF在胰腺组织的表达.Real-time RT PCR检测CTGF的基因表达.Western Blot检测PSCa内α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)及胶原蛋白Ⅰ(CollagenⅠ)水平.结果 胰腺组织纤维化后,PSCs大量活化,并显著表达CTGF.CTGF作用后,PSCs内CTGF mRNA、α-SMA和Collagen Ⅰ的合成均有显著增加,在给予不同的细胞信号通路阻断剂后,PSCs内α-SMA的合成有显著下降,而Collagen Ⅰ的降低没有表现出统计学差异.结论 CTGF参与了胰腺纤维化的调控,MAPK和PI3-K信号通路均参与了CTGF的调控作用.

Mechanism of connective tissue growth factor in the process of pancreatic fibrosis

Objective 1. To observe the expression of connective tissue growth factor（CTGF） in fibrotic pancreas. 2. To evaluate the effects of CTGF on the function of pancreatic stellate cells（PSCs）, and to gain further insights into the signal transduction pathway involved in the regulation of PSCs. Methods The animal model of fibrosis was built with high fat diets. Histopathologic changes were observed by H-E and Sirius red staining for fibrosis, immunohistochemical staining of the pancreatic stellate cells and CTGF for detecting PSCs activation and CTGF expression in rat CTGF autocrine loop was detected by real-time RT-PCR, PSCs activation and collagen Ⅰ synthesis were determined using Western Blot. Results There were abundant activated PSCs in fibrotic pancreas. CTGF was expressed markedly by activated PSCs. Real-time RT-PCR studies revealed that exogenous CTGF enhanced CTGF mRNA expression in PSCs markedly, while the expression in PSCs was blocked by MAPK or PI3-K pathway antagonist. Exogenous CTGF also stimulated α-SMA and collagen Ⅰ synthesis. With the application of MAPK or PI3-K pathway antagonist, the α-SMA synthesis decreased significantly, but the collagen Ⅰ synthesis decreased in signifi cantly. Conclusion CTGF participates in the regulation of pancreatic fibrosis development, and the function of CTGF on PSCs is regulated by MAPK and PI3-K pathways.