Aqueous extract of Peperomia pellucida (L.) HBK accelerates fracture healing in Wistar rats.

BACKGROUND: Peperomia pellucida (L.) HBK is consumed as vegetable and used in Cameroonian traditional medicine for the management of diseases and for fracture healing. Therefore the aim of this study was to evaluate the effects of the aqueous whole plant extract of Peperomia pellucida on fracture healing in female Wistar rats. METHODS: A drill hole injury was created by inserting a drill bit inthe diaphysis of the femur. The aqueous extract of the whole plant of Peperomia pellucida was administered orally at the doses of 100, 200 and 400 mg/kg to adult female Wistar rats. The vehicle (distilled water) was given to the control. Besides these rats, one group of rats without fracture received the extract (400 mg/kg). After 14 days of treatment, the rats were sacrificed under anesthesia and the effects of the extract were evaluated on body weight, the relative weights of organs (femurs, uteri and ovaries) and on hematology. Bone (calcium, phosphorus, alkaline phosphatase) and serum biochemical parameters (calcium, phosphorus, alkaline phosphatase) were also evaluated. Radiological and histological tests were carried out on the femurs. The mineral content of the plant extract was also investigated. RESULTS: The extract induced an increase in body weight at high dose and in WBCs count at low doses. Aqueous extract from Peperomia pellucida increased bone calcium at lowest dose but maintained this parameter at normal range at high dose in fractured rat. Alkaline phophatase and phosphorus concentrations reduced significantly (p < 0.01) at the dose of 400 mg/kg as compared to fractured rats. Moreover, radiological tests revealed a dose dependent formation of callus at the level of the fracture gap, confirmed by the formation of a highly dense and compact fibrocartilagenous callus. The mineral content of the plant extract revealed the presence of calcium, phosphorus, magnesium, sodium and potassium. CONCLUSION: The aqueous extract of P. pellucida accelerates bone healing due partly to the mineral content of the extract. These results confirm its traditional use in the treatment of bone fractures.

Antidiabetic and antioxidant effects of Annona muricata (Annonaceae), aqueous extract on streptozotocin-induced diabetic rats.

ETHNOPHARMACOLOGICAL RELEVANCE: The leaves of Annona muricata are used in Cameroon to manage diabetes and its complications. The aim of this study was to evaluate the antidiabetic, antioxidant activities and the potential toxicity of aqueous extract of Annona muricata in streptozotocin-induced diabetic rats. MATERIAL AND METHODS: Oral administration of Annona muricata aqueous extract (100mg/kg or 200mg/kg) was studied in normal and streptozotocin-induced diabetic rats. In long term treatment, 2 weeks after streptozotocin-induced diabetic rats, animals received plant extract during 28 consecutive days. For a protective effect, extract was administered 3 days prior to streptozotocin exposure and animals were observed 2 weeks without treatment. RESULTS: The plant extract was not effective in normal rats. In diabetic rats, single administration of the extract significantly reduced blood glucose levels by 75% and 58.22% respectively at the dose of 100mg/kg and 200mg/kg as compared to the initial value. Treatment of normal rats 3 days prior to diabetes induction showed that, Annona muricata extract has no effect within 72h following STZ injection. However, after 14 days post-treatment, the extract at the dose of 100mg/kg significantly reduced blood glucose levels as compared with initial value and diabetic control rats. Immunohistochemical staining of pancreatic ß-cells of diabetic rats treated with the dose of 100mg/kg expressed strong staining for ß-cell compared to diabetic control. In a long-term study daily administration of Annona muricata aqueous extract for 28 days to diabetic rats, reduced blood glucose levels, serum creatinine, MDA, AST, ALT activity, and nitrite levels LDL-cholesterol. Total cholesterol, triglycerides, SOD, and CAT activity contents were restored. CONCLUSION: These different results show that the antidiabetic activity of Annona muricata aqueous extract can be explained by its hypolipidaemic effect, its antioxidant and protective action on pancreatic ß-cells, which in turn improve glucose metabolism.