Hyperglycaemia enhances glucose and sodium reabsorption via SGLT2 and SGLT1.Intracellular glucose accumulation in PT cells leads to hypertrophy, hyperreabsorption, hyperfiltration and increased reactive oxygen species production.Diabetic nephropathy shows early structural changes and functional decline in PT cells.Observed in diabetes and diabetic nephropathy in animal models and clinical studies. This evidence concerns the gene SLC5A1 and diabetic kidney disease.