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.