Assessment of Hematological Indices, Antimicrobial, Fertility, and Histological Effects of Selected Plant Extracts Using an Animal Model

Abstract

Medicinal plants are widely consumed in Nigeria for presumed health benefits, yet many are used without systematic evaluation of their physiological effects beyond their traditionally claimed use, leaving open questions about both efficacy and safety. This study assessed the hematological, antimicrobial, fertility, and histological effects of aqueous leaf extracts of Moringa oleifera and Azadirachta indica (neem) using an albino rat model. Eighteen adult male Wistar rats were randomly assigned to three groups (n = 6): normal control (distilled water), Moringa oleifera extract (400 mg/kg), and Azadirachta indica extract (400 mg/kg), administered orally once daily for 28 days. Antimicrobial activity of both extracts was additionally evaluated in vitro against four bacterial pathogens by agar well diffusion. Moringa oleifera significantly improved packed cell volume, hemoglobin, and red blood cell count relative to control (p < .05), with no adverse effect on sperm parameters, testosterone, or testicular and hepatic histology. In contrast, Azadirachta indica produced a significant reduction in packed cell volume and hemoglobin, and significantly impaired sperm count, motility, normal morphology, and serum testosterone relative to control (p < .05), with histopathological examination revealing disrupted germinal epithelium and depleted spermatogenic cells in the testes, alongside mild hepatic vacuolation. Both extracts showed appreciable in vitro antimicrobial activity against all four test organisms, with Azadirachta indica showing the larger zones of inhibition. These findings indicate that while both plants possess notable antimicrobial activity, Moringa oleifera appears hematologically beneficial and reproductively safe at the tested dose, whereas Azadirachta indica raises hematological and reproductive toxicity concerns that warrant caution regarding its traditional use, particularly among men of reproductive age.