Akash Kanzar, Subhash Bodhankar, arulmozhi s, Mahesh Ghaisas, Kakasaheb Mahadik
Background-Curcumin is one of the principle substances found in the rhizome of Curcuma longa L. Piperine, an alkaloid separated from Piper nigrum L., has bioenhancer property.
Objective- The objective of the present study was to evaluate the nephroprotective activity of curcumin when administered concomitantly with piperine in diabetic rats.
Methods- Male Wistar rats were divided into eight groups viz. vehicle control, disease control,   glibenclamide (1), glibenclamide + piperine (1+50) , curcumin (50), curcumin+ piperine (50+10), curcumin + piperine (50+30), curcumin + piperine (50+50). Overnight fasted rats were administered nicotinamide (110 mg/kg, i.p.) and 15 min after nicotinamide injection, streptozotocin (65 mg/kg, i.p.) was injected in all groups except group 1. Curcumin and piperine combination was administered as 2% Tween 80 suspension. Curcumin was administered (50 mg/kg) by oral route. Piperine was administered (10, 30, 50 mg/kg) through the oral route in combination with curcumin. Treatment proceeded up to 6 weeks. Biochemical, antioxidant parameters and histopathological studies were carried out at the end of the study.
 Result- Curcumin + piperine (50+50 mg/kg) administration caused a significant decrease in blood glucose, triglyceride, serum creatinine, serum uric acid, urine creatinine, and urine albumin levels. The antioxidant activity of the combination was evident as there was a significant increase in kidney GSH and SOD levels along with significant decrease in MDA. The histopathological study showed reduced damage to kidney in curcumin + piperine (50+50 mg/kg) group.
Conclusion- It is thus concluded that curcumin in combination with piperine showed enhanced nephroprotective activity in diabetic rats.
