MTOR and diabetic kidney disease: Mesenchymal stem cell (MSC)-derived exosomes downregulate serum creatinine, blood urea nitrogen and proteinuria, decrease mesangial expansion and collagen fibers around glomerular capillaries and the tubules, with obvious upregulating of LC3 and Beclin-1 and downregulating of mTOR, indicating that autophagy induced by exosomes may attenuate the clinical and pathological manifestation of DKD in the STZ-DM rats (Ebrahim et al., 2018).