Immunomodulatory and Anti-Inflammatory Effects of Aframomum Melegueta on Lead-Induced TNF-á and IL-10 Imbalance in Wistar Rats

Abstract

Lead (Pb) exposure is a persistent global health concern, particularly in developing countries, causing multi-organ toxicity through oxidative stress, immune dysregulation, and inflammatory responses. Dysregulation of cytokines, including elevated tumor necrosis factor-alpha (TNF-á) and suppressed interleukin-10 (IL-10), represents a key mechanism of lead-induced immunotoxicity. Natural agents with antioxidant and immunomodulatory properties, such as Aframomum melegueta (alligator pepper), may offer protective benefits. This study evaluated the immunomodulatory and anti-inflammatory effects of ethanolic extract of A. melegueta on lead-induced TNF-á and IL-10 dysregulation in Wistar rats, compared with standard chelation therapy (EDTA). Thirty-five adult Wistar rats were randomly assigned to five groups, including normal control, lead-exposed untreated, lead-exposed treated with low (200 mg/kg), high (400 mg/kg) doses of A. melegueta, EDTA-treated. Lead acetate (100 mg/kg) was administered by gastric gavage for 14 days, followed by 14 and 5 days of treatment for extract and Standard chelator respectively. Serum TNF-á and IL-10 levels were measured via ELISA. Data were expressed as mean ± SEM and analyzed using student t- test (p < 0.05). Lead exposure significantly elevated TNF-á and suppressed IL-10, indicating pronounced inflammatory and immunosuppressive effects. Treatment with A. melegueta extract, particularly at 400 mg/kg, significantly reduced TNF-á and restored IL-10 levels, comparable to calcium disodium EDTA treatment.