Histological and toxicological effects of crude oil-contaminated Mangifera indica stem bark extracts on rat liver, kidney, and heart

Medicinal plants like Mangifera indica (mango) have been integral to traditional medicine since prehistoric times, synthesizing numerous chemical compounds for defense against diseases and parasites. This study investigated the toxicological effects of Mangifera indica stem barks from oil-polluted (C) and uncontaminated (F) sites in Nigeria in animals. Stem barks from Mangifera indica were collected from oil-polluted agricultural land in Umuechem, Rivers State (C), and an uncontaminated site at the University of Benin, Edo State (F), authenticated, and processed into fine powders for analysis. Aqueous extracts were prepared by soaking 100 g of powder in 1000 ml distilled water, filtered, concentrated, and freeze-dried. Eighty female Wistar albino rats, split into five groups of 16, received daily oral doses for 90 days: control (saline), C-250 mg/kg, C-3500 mg/kg, F-250 mg/kg, and F-3500 mg/kg, adjusted to body weight and administered via gavage. After sacrifice on day 90, histopathological analysis revealed normal liver and kidney morphology in the control and F-treated groups (250 and 3500 mg/kg). However, the C-250 and C-3500 groups displayed severe renal tubular necrosis, glomerular collagen buildup, and liver inflammation with fatty changes, signaling toxicity from oil-polluted extracts. All groups showed normal heart morphology. Phytochemical screening confirmed bioactive compounds, but oil pollution likely introduced toxicants, exacerbating organ damage. This study underscores the impact of environmental contamination on medicinal plant safety, suggesting caution in their therapeutic use from polluted regions.