Effect of astaxanthin on expression of type Ⅰ and type Ⅲ collagen in cardiac fibroblasts and its mechanism based on TGF-β1/Smad3 signaling pathway / 中国药理学通报

ABSTRACT

Aim To observe the effects of astaxanthin ( ASTX) on the expression of collegeⅠ( ColⅠ) and type Ⅲcollagen ( Col Ⅲ) of cardiac fibroblasts( CFs) which caused by transforming growth factor β1 ( TGF-β1) and to explore its mechanism of action. Methods CFs were induced by TGF-β1 , and then pretreated with different concentrations of ASTX ( 0 , 5 , 10 , 20 , 40, 80, 160 μmol·L-1) for 24 h. MTT assay was used to determine the activity of CFs. The activation of ROS in CFs cells was detected by DCFH-DA kit. Smad3 gene was silenced by siRNA technique, and re-al-time PCR was used to detect the expression of ColⅠ, Col Ⅲ mRNA before and after Smad3 silencing. Western blot was used to detect the expression of ColⅠ, Col Ⅲ and Smad3 protein levels before and after Smad3 silencing. Results ASTX had no obvious cyto-toxicity in the range of 0 ～20 μmol · L-1 , and could significantly reduce ROS production induced by TGF-β1 in CFs (P<0.05). In addition, ASTX significant-ly inhibited the expression of ColⅠand ColⅢmRNA and protein ( P<0.01 ) of TGF-β1-induced CFs in a concentration-dependent manner. Also, ASTX could significantly down-regulate phosphorylation of Smad3 in TGF-β1-induced CFs ( P <0.01 ) . The expression of Col Ⅰ and Col Ⅲ mRNA and protein was also signifi-cantly down-regulated by Smad3 gene silencing ( P <0.01 ) . Conclusions ASTX can effectively inhibit the expression of Col Ⅰ, Col Ⅲ mRNA and protein of TGF-β1-induced CFs, and the possible mechanism may involve the down-regulation of Smad3 phosphoryla-tion.