Effects of the Methanolic Extract of Vitellaria paradoxa Stem Bark Against Scopolamine-Induced Cognitive Dysfunction and Oxidative Stress in the Rat Hippocampus.

Vitellaria paradoxa C.F. Gaertn (Sapotaceae) is a perennial three which naturally grows in the northern part of Cameroon. It has been traditionally used in the Cameroonian folk medicine for treating inflammation and pain. In the present study, we evaluate the possible anti-amnesic and antioxidative effects of the methanolic extract of V. paradoxa stem bark in an Alzheimer's disease (AD) rat model of scopolamine. Rats received a single injection of scopolamine (1.5 mg/kg) before behavioral testing and were treated with the methanolic extract (25 and 50 mg/kg), daily, for eight continuous days. Also, the antioxidant activity in the hippocampus was assessed using the total content of reduced glutathione and malondialdehyde levels. The scopolamine-treated rats exhibited the following: decrease of exploratory time and discrimination index within the novel object recognition test, decrease of spontaneous alternations percentage within Y-maze task, and increase of working memory errors, reference memory errors, and time taken to consume all five baits within radial arm-maze task. Administration of the methanolic extract significantly improved these parameters, suggesting positive effects on memory formation processes and antioxidant potential. Our results suggest that the methanolic extract ameliorates scopolamine-induced memory impairment by attenuation of the oxidative stress in the rat hippocampus.

Anti-inflammatory and anti-arthritic activity of a methanol extract from Vitellaria paradoxa stem bark.

BACKGROUND: Vitellaria paradoxa is a traditional medicinal plant of Cameroon. Several studies on this plant have focused on the cosmetic profile of its fruits. The present study focuses on the anti-inflammatory potency of stem barks extract of this plant. OBJECTIVE: The objective was to evaluate the effect of methanolic extract of V. paradoxa (VPME) stem barks on inflammatory response in rats. MATERIALS AND METHODS: Anti-inflammatory effects of VPME were evaluated in acute and chronic (28 days) inflammation induced in Wistar albino rats. The effects on hyperalgesia and locomotors activity were also quantified. The relative weight of lymphoid organs was obtained as well as some hematological parameters. RESULTS: In the carrageenan-induced inflammation, VPME (75 mg/kg) exhibited a significant (66.67%) inhibition after 1 h. On the complete Freund's adjuvant-induced rheumatoid arthritis, VPME showed a significant protective effect with 8.12% inflammation against 25.00% for the control group after 2 days of the treatment. The extract (75 and 150 mg/kg) significantly reduced the score of arthritis with a maximum obtained on day 19(th) of the experimentation. There was a significant increase in the reaction time of rats on the hot plate as well as the exploratory activities of the animals in the open field. This extract significantly prevented weight, hemoglobin and red blood cells losses, and spleen hypertrophy. A protective action against skin destruction and cartilage erosion was evident. Liquid chromatography-mass spectrometry analysis of the extract revealed the presence of catechins. CONCLUSIONS: These findings suggested that V. paradoxa may contribute to the reduction of the inflammatory response.