Comparative effects of candesartan and losartan on mesangial expansion and glomerular volume in diabetes rat model receiving rosmarinic acid therapy

 An oxidative stress and angiotensin II (Ang II) contribute significantly in the pathogenesis of diabetic nephropathy (DN). Therefore, interventions targeting these factors are anticipated to significantly contribute to inhibiting the progression of diabetic kidney disease.

 The aim of this study was to assess the impact of a combination of rosmarinic acid (RA) and angiotensin receptor blockers (ARBs) in preventing mesangial expansion and reducing glomerular volume in streptozotocin (STZ)-induced diabetic rats.

 We observed experimental animals, 16 adults male Wistar rats, which were randomly grouped into 4 groups (n=4 per group): negative and positive control groups and diabetic rats treated with RA 75 mg/kg and candesartan 1 mg/kg (treatment group 1) and RA therapy 75 mg/kg and losartan 2.5 mg/kg (treatment group 2). Following 8 weeks of therapy, the renal histology was assessed to evaluate mesangial expansion and glomerular volume.

 In comparison to the positive control, treatment group 1 demonstrated a significant inhibition of mesangial expansion (MD: -19.92; 95% CI: -21.97, -17.87; P<0.001) and decreased glomerular volume (MD: 2669.06; 95% CI: 2066.31, 3271.80; P<0.001). Similarly, treatment group 2 significantly inhibited mesangial expansion (MD: -19.21; 95% CI: -21.26, -17.16; P<0.001) and decreased glomerular volume (MD: 2488.04; 95% CI: 1885.29, 3090.78; P<0.001) compared to the positive control. While treatment group 1 exhibited better effects than treatment group 2, although the difference was not statistically significant.

 In STZ-induced diabetic rats, combination therapy of RA with candesartan or losartan can inhibit mesangial expansion and decrease glomerular volume.