Immunomodulatory Activity of Moringa Oleifera Lam. Leaf Ethanol Extract on BV2 Cell Line

Abstract

Introduction: Moringa oleifera, known as Kelor in Malay and Murunggai in Tamil, is widely recognised for its nutritional and therapeutic benefits. Its leaves contain bioactive compounds such as flavonoids and polyphenols that confer antioxidant, anti-inflammatory, and anticancer properties. Modulating the unwanted inflammatory responses of microglia has become a key strategy in slowing neuroinflammation and the progression of neurodegenerative diseases. Objectives: This study aimed to evaluate the effects of Moringa oleifera ethanol extract (MoETE) on the pro-inflammatory responses of BV2 microglial cells. Methods: Cytotoxicity was determined using the MTT assay. The immunomodulatory potential of MoETE was assessed by measuring nitric oxide (NO) production and apoptosis in BV2 cells stimulated with 1 µg/mL LPS, using the Griess assay and flow cytometry, respectively. Experiments were performed in triplicate (n = 3). Data were analysed using one-way ANOVA followed by Dunnett’s and Sidak’s post hoc tests. Results: MoETE supported BV2 viability between 0.1–100 µg/mL but significantly reduced viability at 1000 µg/mL (46.44%, p < 0.0001). NO levels decreased significantly (p < 0.05) in LPS-stimulated cells treated with low MoETE concentrations (0.1–100 µg/mL) compared to controls, whereas higher concentrations (200–1000 µg/mL) restored NO production and induced apoptosis. Conclusion: MoETE demonstrates dose-dependent effects on microglial cells, exhibiting anti-inflammatory and neuroprotective potential at low concentrations but cytotoxicity and pro-inflammatory effects at higher doses. These findings suggest that controlled low-dose MoETE may beneficially modulate microglial activity to mitigate neuroinflammation.