Understanding of Evidence and Molecular Mechanisms for the Four Pillars of Treatments for Diabetic Kidney Disease, and Its Promising Optional Treatments

Diabetic kidney disease (DKD) is one of the most serious complications of diabetes and the leading cause of end-stage renal disease worldwide. Recently, renin-angiotensin system inhibitors, non-steroidal mineralocorticoid receptor antagonists, sodium-glucose cotransporter 2 inhibitors, and glucagon-like peptide-1 receptor agonists have been proposed as the four pillars for treating DKD. To understand the molecular mechanisms by which these drugs improve DKD, we described the histological and molecular changes due to diabetes. Based on our understanding of the molecular changes in DKD, we present evidence on the efficacy of these drugs in improving DKD and discuss why such drugs improve the prognosis of DKD. In addition to diabetes and hypertension, insulin resistance, dyslipidemia and hyperuricemia are risk factors for DKD. Metformin, fibrates, and febuxostat have been reported to improve DKD, however, caution is required when administering these drugs to patients with renal impairment due to concerns about the onset of lactic acidosis, rhabdomyolysis, and deterioration of renal function, respectively. Imeglimin, pemafibrate, and dotinurad have similar chemical structures or effects to metformin, fibrates, and febuxostat, respectively, but are safer in patients with renal impairment. Furthermore, they have specific mechanisms to improve DKD and may offer new options for its treatment.