MTOR and familial dilated cardiomyopathy: However, in diabetic mice, 1,25-dihydroxyvitamin-D3 [1-25(OH)2VitD3] improved myocardial fibrosis and cardiac function in DCM through an autophagy-related vitamin D receptor (VDR)-dependent mechanism and the β-catenin/T-cell factor/lymphoid enhancer factor (TCF4)/glycogen synthase kinase-3β (GSK-3β)/mammalian target of rapamycin (mTOR) pathway (75).