Therapeutic Modulatory Effect of Irvingia wombolu Leaf Fractions in Managing Inflammation and Oxidative Stress
Obumneme Maduka Onyia *
Department of Applied Biochemistry, Enugu State University of Science and Technology, Enugu, Nigeria.
Ikechukwu Jacob Okoro
Department of Medical Biochemistry, College of Health Sciences, David Umahi Federal University of Health Sciences, Uburu, Nigeria.
Chiadikobi Ejikeme Onyia
Department of Microbiology, University of Nigeria, Nsukka, Enugu State, Nigeria.
Obiora Celestine Ugwu
Department of Pharmacology, Faculty of Pharmaceutical Science, Enugu State University of Science and Technology, Enugu, Nigeria.
Onuabuchi Nnenna Ani
Department of Applied Biochemistry, Enugu State University of Science and Technology, Enugu, Nigeria.
Precious Chinenye Nwafor
Department of Medical Biochemistry, Enugu State University of College of Medicine, Enugu, Nigeria.
Victor Nwadiogbu Ogugua
Department of Biochemistry, University of Nigeria, Nsukka, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Background: This study investigated the anti-inflammatory and antioxidant activities of leaf fractions and their effects on selected biochemical indices. Methods: A crude ethanolic leaf extract was partitioned using n-hexane, ethyl acetate, and ethanol. Phytochemical constituents were assessed qualitatively and quantitatively, while in vitro anti-inflammatory activity was determined using phospholipase A₂ inhibition. Twenty-eight albino rats were allocated to seven groups of four animals. Inflammation was induced with 5% formalin, and the animals received aspirin, crude extract, or one of the solvent fractions, as applicable. Paw size, C-reactive protein, malondialdehyde, superoxide dismutase, catalase, reduced glutathione, and serum zinc were evaluated. Results: Alkaloids, flavonoids, terpenoids, steroids, phenolics, tannins, and glycosides were detected in the extract and fractions. The tested samples inhibited phospholipase A₂ activity in a concentration-dependent manner, with the n-hexane fraction showing the highest inhibition. Treatment reduced paw oedema and was associated with lower C-reactive protein and malondialdehyde values than those in the untreated inflamed group. Catalase and reduced glutathione generally increased after treatment, whereas superoxide dismutase responses were less consistent across comparisons. Serum zinc increased most prominently in the n-hexane-treated group. Conclusion: Irvingia wombolu leaf fractions demonstrated anti-inflammatory and antioxidant activity under the experimental conditions, with the n-hexane fraction showing the most consistent overall response. These preclinical findings warrant further chemical characterisation, dose-response assessment, and safety evaluation.
Keywords: C-reactive protein, lipid peroxidation, Irvingia wombolu, formalin, anti-inflammatory, antioxidant