TGFB1 and Myocardial fibrosis: Meanwhile, long-term moderate-intensity exercise countered this effect by reducing cardiac ROS production and oxidative stress levels, which in turn inhibited the expression of pro-fibrotic factors such as TGF-β1, MMP-2/9, CTGF, TIMP-1, as well as collagen types I and III, ultimately leading to an improvement in myocardial fibrosis [114].