Diabetic kidney disease: Its current trends and future therapeutic perspectives

Intravenous injection of human umbilical cord-derived mesenchymal stem cells ameliorates not only blood glucose but also nephrotic complication of diabetic rats through autophagy-mediated anti-senescent mechanism

BACKGROUND

Diabetic nephropathy (DN) is one of the most severe complications of diabetes mellitus, which is characterized by early occurrence of albuminuria and end-stage glomerulosclerosis. Senescence and autophagy of podocytes play an important role in DN development. Human umbilical cord-derived mesenchymal stem cells (hucMSCs) have potential in the treatment of diabetes and its complications. However, the role of hucMSCs in the treatment of DN and the underlying mechanism remain unclear.

METHODS

In vivo, a streptozotocin-induced diabetic male Sprague Dawley rat model was established to determine the renoprotective effect of hucMSCs on DN by biochemical analysis, histopathology, and immunohistochemical staining of renal tissues. And the distribution of hucMSCs in various organs in rats within 168 h was analyzed. In vitro, CCK8 assay, wound healing assay, and β-galactosidase staining were conducted to detect the beneficial effects of hucMSCs on high glucose-induced rat podocytes. Real-time PCR and western blot assays were applied to explore the mechanism of action of hucMSCs.

RESULTS

The in vivo data revealed that hucMSCs were distributed into kidneys and significantly protected kidneys from diabetic damage. The in vitro data indicated that hucMSCs improved cell viability, wound healing, senescence of the high glucose-damaged rat podocytes through a paracrine action mode. Besides, the altered expressions of senescence-associated genes (p16, p53, and p21) and autophagy-associated genes (Beclin-1, p62, and LC3) were improved by hucMSCs. Mechanistically, hucMSCs protected high glucose-induced injury in rat podocytes by activating autophagy and attenuating senescence through the AMPK/mTOR pathway.

CONCLUSIONS

In conclusion, hucMSCs might be a promising therapeutic strategy for the clinical treatment of DN-induced renal damages.

Recent evidence in the etiology and treatment for diabetic kidney disease

Etiology and therapeutic targets of diabetic nephropathy.

Significance of SGLT2 inhibitors: lessons from renal clinical outcomes in patients with type 2 diabetes and basic researches

Diabetic kidney disease (DKD), a microvascular complication of diabetes, has been the leading cause of end-stage kidney disease (ESKD). Accordingly, patients with type 2 diabetes mellitus (T2DM) develop renal damage due to multiple metabolic and cardiorenal disease-related risk factors, including hyperglycemia, hypertension, dyslipidemia, hyperuricemia, and overnutrition/obesity. Despite multifactorial management including the administration of renin-angiotensin system inhibitors, patients often do not experience sufficient suppression of DKD progression and, thus, remain at risk for ESKD. Recent studies on cardiovascular outcomes among patients with T2DM have clearly shown that sodium-glucose cotransporter 2 (SGLT2) inhibitors, such as empagliflozin, canagliflozin, and dapagliflozin, have cardiorenal protective effects apart from their glucose-lowering effects. In particular, SGLT2 inhibitors have been found to improve renal outcomes, including ESKD, by slowing renal function decline and reducing urinary albumin excretion through their class effect. The proposed mechanisms for the renoprotective effects of SGLT2 inhibitors include the action of tubulo-glomerular feedback system and attenuation of hypoxia and metabolic stress in proximal tubular cells mediated through the inhibition of excessive glucose and sodium reabsorption, increased erythropoiesis, or increased ketone body production.