Beyond Efficacy

High-Dose Neem Extract Induces Hepatotoxicity in Rats amidst Widespread Aflatoxin Contamination of Nigerian Groundnuts

Résumé

Aflatoxin B1 (AFB1) contamination in staple crops is a major cause of hepatocellular carcinoma in sub-Saharan Africa. Although plant extracts like Azadirachta indica (neem) and Curcuma longa (turmeric) are proposed as low-cost detoxificants, their in vivo efficacy and safety profiles are inadequately characterized. This study first quantified aflatoxin contamination in 300 stored groundnut samples from Nasarawa State, Nigeria, using High-Performance Liquid Chromatography (HPLC). Concurrently, the detoxification potential and toxicity of aqueous extracts of these botanicals were evaluated in an albino rat model. Rats were divided into groups and treated via oral gavage for 28 days with AFB1 alone or in combination with either C. longa or low- (1000 mg/kg) or high-dose (5000 mg/kg) A. indica extract. Serum biochemistry was analyzed using standard diagnostic kits. The groundnut analysis revealed widespread contamination, with 51.3% of samples exceeding the USFDA safety limit (20 µg/kg) and AFB1 levels as high as 1791 µg/kg. In the rat model, high-dose A. indica (5000 mg/kg) significantly elevated serum alanine aminotransferase (92.56 vs. 76.23 IU/L in controls, P < 0.003) and reduced total protein, indicating hepatotoxicity. C. longa showed no significant biochemical alterations. These findings highlight a serious public health risk from aflatoxin exposure and reveal a dose-dependent hepatotoxicity that severely limits the therapeutic use of high-dose neem extract. The promotion of plant-based detoxification requires caution, underscoring the urgent need to improve post-harvest storage infrastructure to mitigate contamination at its source.