SMAD3 and Myocardial fibrosis: ↓ Heart weight; ↓ Heart weight/body weight ratio; ↓ LVEDD; ↓ LVESD; ↓ Myocardial fibrosis; ↓ Col I; ↓ Col III; ↑ SIRT1 mRNA; ↓ Ac-Smad3