Attenuation of epithelial-mesenchymal transition via SGLT2 inhibition and diabetic cataract suppression by dapagliflozin nanoparticles treatment

Chronic hyperglycemia triggers overproduction of AKR1B1 (aldo-keto reductase family 1 member B) and receptor for advanced glycation end product (RAGE), which causes epithelial-mesenchymal transition (EMT) in the lens epithelial cells (LECs) of diabetic mellitus (DM) cataracts. However, it is unclear whether EMT in LECs is related to abnormal increase of SGLT2. Sodium glucose cotransporter 2 (SGLT2) inhibitor, also known as dapagliflozin (Dapa) can be used to treat diabetes. Here, we examined how Dapa or nano eye-drops (DapaN) reduce EMT in LECs of DM cataracts. The nano eye-drop provides an ophthalmic treatment that suppressed diabetic cataract progression and improved potency with reduced side effects. SD rats were injected with streptozocin (STZ) (65 mg/kg, ip), nano-Dapa drops (0.456 mg/10 ml/eye) or Dapa (1.2 mg/kg/day) treatment for 6–12 weeks. Immunofluorescence staining was used for protein quantification of RAGE, SGLT2, N-cadherin and E-cadherin in the LECs of rats. In this study, Dapa applies nanotechnology-based delivery system and it contains polyvinylpyrrolidone (PVP) and HPBCD. Dapa showed therapeutic effect on DM cataracts, wherein it targeted EMT biomarker, E-cadherin. The nano-Dapa drops or oral Dapa inhibited SGLT2, suppressed AKR1B1 expression, decreased AcSOD2- and RAGE-induced EMT in diabetic cataracts. Our findings suggest that nanotechnology-based Dapa eye drops (Dapa-PVP-HPBCD) can effectively improve solubility of Dapa in aqueous solution. Taken together, results suggest that the SGLT2-mediated DM cataract therapy may involve the AKR1B1-RAGE-AcSOD2-EMT pathway. The nano eye drops and Dapa show potential beneficial effects for cataract prevention. This study conveys new insights into cataract treatment and supplementation of nano-Dapa drops shows promising result in preventing diabetic cataracts.