ABSTRACT
BACKGROUND: Parquetina nigrescens is among the evergreen plants native to West Africa. It is used in the management of various ailments including anemia, fever, asthma and diabetes. This study evaluated the antidiabetic and antihyperlipidemic effect of Parquetina nigrescens in streptozotocin-nicotinamide-induced type 2 diabetic rats. METHODS: Type 2 diabetes mellitus was induced in overnight fasted rats with a single intraperitoneal injection of streptozotocin (60 mg/kg), followed by the administration of nicotinamide (120 mg/kg) after an interval of 15 min. Diabetic rats were orally administered with; 200, 400 and 800 mg/kg of aqueous extract of Parquetina nigrescens (AEPN), metformin (180 mg/kg) and glibenclamide (1 mg/kg) for two weeks. The effect of treatments on fasting blood glucose, serum insulin, leptin, adiponectin, homa-ir, lipid profile, body weight, pancreatic antioxidants parameters, hepatic glycogen content, glucose-6-phosphate activity, α-amylase inhibition, α-glucosidase inhibition, lipase inhibition and histology of the organs were evaluated. RESULTS: Data from this study showed that treatment with AEPN produced a significant reduction (p < 0.05) in fasting blood glucose, glucose-6-phosphatase activity, serum lipase, total triglyceride, total cholesterol, low-density lipoproteins, very low-density lipoprotein, atherogenic index, coronary risk index, pancreatic α-amylase, α-glucosidase and lipase activities. Treatment with AEPN also produced a significant (p < 0.05) increase in; glucose tolerance, glycogen content, leptin, adiponectin and pancreatic antioxidants (glutathione, superoxide dismutase, catalase and high-density lipoproteins). The histology of the organ showed regeneration of the pancreatic tissue after treatment with AEPN. CONCLUSIONS: This study showed that AEPN exhibited antidiabetic and antihyperlipidemic activity in streptozotocin-nicotinamide-induced type 2 diabetic rats.
ABSTRACT
The leaf extract of Turraea vogelii Hook. f. ex. Benth. is used in ethnomedicine for the management of pain and inflammation. Anti-nociceptive activity was determined using acetic acid-induced mouse writhing model. The anti-inflammatory activity was investigated using in-vitro bovine serum albumin (BSA) denaturation assay and BSA-induced hind paw edema in rats. The extract (125-500 mg/kg) administered via the oral route produced a significant (p<0.005) inhibition of acetic acid-induced writhes. The percent inhibition of writhes for extract (500 mg/kg) and diclofenac (10 mg/kg) was 53.3 and 59.5% respectively. The methanol extract (10-6-1.0 µg/mL) inhibited protein denaturation with IC50values of (1.06 × 10-3 µg/mL and 2.58 × 10-3 µg/mL) for extract and diclofenac respectively. Furthermore, the leaf extract (62.5 mg/kg) significantly (p<0.05) inhibited BSA-induced paw edema in rats. The methanol leaf extract of T. vogelii has anti-nociceptive and anti-inflammatory activities. These findings justify the use of the plant in traditional medicine for the management of pain and inflammation.