Effect of empagliflozin on urinary albumin excretion and hypoxic biomarkers in early diabetic kidney disease: A randomised double-blind, placebo-controlled trial

Abstract

Aims: The precise mechanism of sodium glucose co-transporter 2 (SGLT2) inhibitor on reno-protective effect has been still unclear. In this study, we hypothesised that SGLT2 inhibitor prevents diabetic kidney disease via reduction of hypoxia-induced factors. Materials and Methods: In this multicenter, prospective, randomised, double blinded clinical trial, people with type 2 diabetes and microalbuminuria were randomised equally to empagliflozin (10 mg/day) (n = 40) and placebo (n = 39) and followed 24 weeks. The primary endpoint was change in urinary albumin creatinine ratio (ACR) and urinary liver type fatty acid binding protein (L-FABP) excretion from baseline to 24 weeks. Major secondary outcome was change in serum vascular endothelial growth factor (VEGF), angiopoietin-like proteins 2 (ANGPTL2), angiopoietin-like proteins 4 (ANGPTL4), and adrenomedullin (AM) levels. Results: Although the reduction of ACR was significantly greater in the empagliflozin group than the placebo group at 4 and 12 weeks, the difference of change at 24 weeks between the two groups was not statistically significant (Empagliflozin group—Placebo group: −0.3643, 95% CI: −0.7571 to 0.0285, p = 0.0686). There was no difference in urinary L-FABP excretion between the empagliflozin and placebo groups. Serum VEGF and ANGPTL2 decreased significantly more in the empagliflozin group, whereas there were no significant differences in AM and ANGPTL4. Conclusions: These results demonstrated that empagliflozin partially suppressed the hypoxia-induced angiogenic factors overproduction in addition to a declining trend in ACR in the early stage of diabetic kidney disease, which might contribute to the mechanisms of reno-protective effects of this agent (jRCTs051200147).