Anti-inflammatory Potential of Vernonia amygdalina Delile Extract: In Vitro Studies

Abstract

Vernonia amygdalina, commonly known as bitter leaf, widely used in traditional medicine across Africa and Asia, and is characterized by its bitter taste due to the presence of bioactive compounds such as flavonoids, alkaloids, saponins, and terpenoids. The study aimed to evaluate the effectiveness of Bitter Leaf (Vernonia amygdalina Delile) extract in suppressing pro-inflammatory cytokines and reducing phagocytic activity in cell-based assays. The Bitter leaf extract was prepared through a maceration process with ethanol solvent. To assess the anti-inflammatory potential of the extract, RAW 264.7 macrophage cells were employed. Cytotoxicity and the safe concentration of the extract in the cells were established using the MTT assay. The cells were treated with different amounts of extract, and then lipopolysaccharide (LPS) was added to cause inflammation. ELISA was used to assess the extract's capacity to decrease the release of pro-inflammatory cytokines, Tumor Necrosis Factor-alpha (TNF-α) and Interleukin-6 (IL-6), while phagocytic activity was evaluated using the neutral red uptake assay. The extract derived from Bitter leaves has been shown to enhance the proliferation of RAW 264.7 macrophage cells. This indicates its potential to stimulate cellular growth in the immune system. Despite this, the extract significantly decreases the phagocytic activity of these macrophage cells. Additionally, it suppresses the secretion of pro-inflammatory cytokines, IL-6 and TNF-α. The Bitter leaf extract shows anti-inflammatory properties and could be prepared in the form of an anti-inflammatory drug.