Ferula assa-foetida oleo gum resin ethanolic extract alleviated the pancreatic changes and antioxidant status in streptozotocin-induced diabetic rats: A biochemical, histopathological, and ultrastructural study

The effect of Iranian snake, Naja naja oxiana venom on the blood glucose concentration and some biochemical parameters of experimental diabetic rats

Diabetes is a chronic disease resulting from impaired insulin production and function; leading to hyperglycaemia and long-term complications. The treatment for Type I diabetes treatment involves insulin injections while Type II diabetes treatments include drugs such as metformin and sulfonylureas, along with lifestyle changes. These medicines can be expensive and may have adverse effects. Therefore, the search for new therapeutic agents continues. Venoms from various animals yield numerous pharmacologically active compounds. In this study, we investigated the effects of the venom from an Iranian snake, Naja naja oxiana, on blood glucose concentration and certain serum biochemical parameters in male rats with induced diabetes. Diabetes was induced in male rats using either a single injection of streptozotocin (STZ) alone (55 mg/kg i. p.) or STZ (65 mg/kg i. p.) preceded by nicotinamide (230/kg i. p.) administered 15 min earlier. The diabetic rats produced by either method received a single injection of either vehicle or venom (0.2 or 0.4 mg/kg i. p.). In the STZ rats, this was done 13 days after diabetes induction, while in the STZ-nicotinamide rats, venom was injected 3 days after diabetes induction. The venom from Naja naja oxiana significantly reduced blood glucose levels in male rats with diabetes induced by either method. Additionally, the venom decreased serum cholesterol and triglycerides concentrations. However, the venom had no effect on the blood glucose levels of healthy male rats. Pretreatment with the venom did not prevent the induction of diabetes by STZ. These findings suggest that Naja naja oxiana venom exhibits an anti-diabetic effect and could be a potential candidate for effectively controlling diabetes.

Antidiabetic activity of Solanum torvum fruit extract in streptozotocin-induced diabetic rats

Background

Solanum torvum Swartz, a medicinal plant belonging to the family Solanaceae, is an important medicinal plant widely distributed throughout the world and used as medicine to treat diabetes, hypertension, tooth decay, and reproductive problems in traditional systems of medicine around the world including Malaysia. The objective of this study was to investigate hypoglycemic, antilipidemic, and hepatoprotective activities, histopathology of the pancreas, and specific glucose regulating gene expression of the ethanolic extract of S. torvum fruit in streptozotocin-induced diabetic Sprague–Dawley rats.

Materials and methods

Acute toxicity study was done according to OECD-423 guidelines. Diabetes was induced by intraperitoneal (i.p.) injection of streptozotocin (55 mg/kg) in male Sprague–Dawley rats. Experimental diabetic rats were divided into six different groups; normal, diabetic control, and glibenclamide at 6 mg/kg body weight, and the other three groups of animals were treated with oral administration of ethanolic extract of S. torvum fruit at 120, 160, and 200 mg/kg for 28 days. The effect of ethanolic extract of S. torvum fruit on body weight, blood glucose, lipid profile, liver enzymes, histopathology of pancreas, and gene expression of glucose transporter 2 (slc2a2), and phosphoenolpyruvate carboxykinase (PCK1) was determined by RT-PCR.

Results

Acute toxicity studies showed LD₅₀ of ethanolic extract of S. torvum fruit to be at the dose of 1600 mg/kg body weight. Blood glucose, total cholesterol, triglycerides, low-density lipoproteins, very low-density lipoproteins, serum alanine aminotransferase, and aspartate aminotransferase were significantly reduced, whereas high-density lipoproteins were significantly increased in S. torvum fruit (200 mg/kg)-treated rats. Histopathological study of the pancreas showed an increase in number, size, and regeneration of β-cell of islets of Langerhans. Gene expression studies revealed the lower expression of slc2a2 and PCK1 in treated animals when compared to diabetic control.

Conclusion

Ethanolic extract of S. torvum fruits showed hypoglycemic, hypolipidemic, and hepatoprotective activity in streptozocin-induced diabetic rats. Histopathological studies revealed regeneration of β cells of islets of Langerhans. Gene expression studies indicated lower expression of slc2a2 and PCK1 in treated animals when compared to diabetic control, indicating that the treated animals prefer the gluconeogenesis pathway.