CURCUMIN, THE ACTIVE PRINCIPLE OF TURMERIC (CURCUMA LONGA), AMELIORATES DIABETIC NEPHROPATHY IN RATS

Abstract

Chronic hyperglycaemia in diabetes leads to the overproduction of free radicals and evidence is increasing that these contribute to the development of diabetic nephropathy. Among the spices, turmeric (Curcuma longa) is used as a flavouring and colouring agent in the indian diet every day and is known to possess anti-oxidant properties. The present study was designed to examine the effect of curcumin, a yellow pigment of turmeric, on renal function and oxidative stress in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced by a single intraperitoneal injection of STZ (65 mg/kg) in rats. Four weeks after STZ injection, rats were divided into four groups, namely control rats, diabetic rats and diabetic rats treated with curcumin (15 and 30 mg/kg, p.o.) for 2 weeks. Renal function was assessed by creatinine, blood urea nitrogen, creatinine and urea clearance and urine albumin excretion. Oxidative stress was measured by renal malonaldehyde, reduced glutathione and the anti-oxidant enzymes superoxide dismutase and catalase. Streptozotocin-injected rats showed significant increases in blood glucose, polyuria and a decrease in bodyweight compared with age-matched control rats. After 6 weeks, diabetic rats also exhibited renal dysfunction, as evidenced by reduced creatinine and urea clearance and proteinuria, along with a marked increase in oxidative stress, as determined by lipid peroxidation and activities of key anti-oxidant enzymes. Chronic treatment with curcumin significantly attenuated both renal dysfunction and oxidative stress in diabetic rats. These results provide confirmatory evidence of oxidative stress in diabetic nephropathy and point towards the possible anti-oxidative mechanism being responsible for the nephroprotective action of curcumin.

Influence of Combined Administration of Turmeric and Black seed on Selected Biochemical Parameters of Diabetic Rats

“…On other hand, the present study revealed that Turmeric and Black cumin seed mixture was effective in reducing blood glucose concentration. The hypoglycemic effect of Turmeric comes in accordance with those obtained in rats (Arun and Nalini 2002;Sharma et al, 2006). Authors reported that curcumin, the active principles of Turmeric had a beneficial effect on blood glucose in diabetics and increases gastric mucosal secretion in rabbits.…”

Curcumin attenuates high glucose-induced podocyte apoptosis by regulating functional connections between caveolin-1 phosphorylation and ROS

“…Many of these effects limited the development of DN. Furthermore, treatment of diabetic rats with curcumin prevented diabetesinduced cell apoptosis, oxidative stress and kidney dysfunction [7,8] . However, the mechanisms underlying the renoprotective effects of curcumin in DN remain unclear.…”

Inhibition of glycogen synthase kinase by curcumin: Investigation by simulated molecular docking and subsequentin vitro/in vivoevaluation

“…In fact, curcumin has shown wide range of pharmacological activities including antiinflammatory [4,5], hypoglycemic [6,7], anti-oxidant [8], wound healing [9], anti-microbial effects [10], improvement of defects associated with cystic fibrosis [11] and reducing the destructive beta-amyloid in the brains of Alzheimer's disease animal models [12].…”

“…Chronic treatment with curcumin attenuates significantly renal dysfunction and oxidative stress in diabetic animals [6]. Furthermore, curcumin demonstrates potent anticancer and chemopreventive activities [14 -16].…”