Phytochemical screening and hypoglycemic activity of Carica papaya leaf in streptozotocin-induced diabetic rats

The extraction of plant constituents is essential to isolate biologically active compounds, aimed to understand their role on the treatment of diabetes. This study was designed to explore the preliminary phytochemical and physicochemical analysis of Carica papaya L., Caricaceae, leaf, and further evaluation of its hypoglycemic effect on diabetic rats. C. papaya leaves were extracted using chloroform, n-hexane or ethanol. For each extract a phytochemical screening was performed. The tests were conducted in triplicate and the qualitative and quantitative determination of the various metabolites was done using analytical standards proposed by Mexican Herbal Pharmacopoeia. The chloroform extract, containing steroids and quinones as major components, was chosen to study C. papaya biological effects. The chloroform extract was evaporated to dryness, and doses 0, 31, 62, 125 mg/kg were orally administered in 300 µl polyethylene glycol to diabetic rats; and 0 and 62 mg/kg to non-diabetic rats. After a 20-day treatment with the chloroform extract, the animals were sacrificed and blood was obtained for biochemical studies. The main effect observed was a decrease in serum glucose, triglycerides and transaminases in diabetic rats after the administration of C. papaya chloroform extract. These results confirm the potential beneficial action of C. papaya to treat the symptoms of diabetic patients

Hypoglycemic effect of <it>Carica papaya</it> leaves in streptozotocin-induced diabetic rats

<p>Abstract</p> <p>Background</p> <p>Traditional plant treatment for diabetes has shown a surging interest in the last few decades. Therefore, the purpose of this study was to assess the hypoglycemic effect of the aqueous extract of <it>C. papaya</it> leaves in diabetic rats. Several studies have reported that some parts of the <it>C. papaya</it> plant exert hypoglycemic effects in both animals and humans.</p> <p>Methods</p> <p>Diabetes was induced in rats by intraperitoneal administration of 60 mg/kg of streptozotocin (STZ). The aqueous extract of <it>C. papaya</it> was administered in three different doses (0.75, 1.5 and 3 g/100 mL) as drinking water to both diabetic and non-diabetic animals during 4 weeks.</p> <p>Results</p> <p>The aqueous extract of <it>Carica papaya</it> (0.75 g and 1.5 g/100 mL) significantly decreased blood glucose levels (p<0.05) in diabetic rats. It also decreased cholesterol, triacylglycerol and amino-transferases blood levels. Low plasma insulin levels did not change after treatment in diabetic rats, but they significantly increased in non-diabetic animals. Pancreatic islet cells were normal in non-diabetic treated animals, whereas in diabetic treated rats, <it>C. papaya</it> could help islet regeneration manifested as preservation of cell size. In the liver of diabetic treated rats, <it>C. papaya</it> prevented hepatocyte disruption, as well as accumulation of glycogen and lipids. Finally, an antioxidant effect of <it>C. papaya</it> extract was also detected in diabetic rats.</p> <p>Conclusions</p> <p>This study showed that the aqueous extract of <it>C. papaya</it> exerted a hypoglycemic and antioxidant effect; it also improved the lipid profile in diabetic rats. In addition, the leaf extract positively affected integrity and function of both liver and pancreas.</p