Inhibition of vascular endothelial growth factor (VEGF) does not affect early renal changes in a rat model of lean type 2 diabetes

Type 2 diabetes is the most frequent cause of end-stage renal failure in many Western countries. Approximately 10-15% of all type 2 diabetics are lean. Various growth factors and cytokines have been implicated in the pathophysiology of diabetic kidney disease, including vascular endothelial growth factor (VEGF). To elucidate a role for VEGF in the renal changes associated with type 2 diabetes, we examined the effect of a VEGF-antibody (ab) on early renal changes in the Goto-Kakizaki (GK) rat, a lean type 2 diabetes model. GK-rats were treated for 6 weeks with the VEGF-ab or with an isotype-matched irrelevant IgG. Wistar rats were used as non-diabetic controls. Placebo-treated GK-rats showed a pronounced increase in glomerular volume and urinary albumin excretion (UAE) and no change in the renal expression of endothelial nitric oxide synthase (eNOS) compared to placebo-treated non-diabetic controls. Kidney weight and creatinine clearance were no different between the groups. VEGF-ab treatment had no effect on glomerular volume, UAE, eNOS expression, body weight, blood glucose levels or food intake, but lowered serum insulin levels in non-diabetic and diabetic animals. We conclude that VEGF inhibition has minimal effects on early renal changes in GK-rats.