Antidiarrheal effects of Vigna subterranea seed extract via modulation of intestinal Na⁺/K⁺-ATPase and antioxidant enzymes

Abstract

Abstract. Nurudeen QO, Alhassan JD, Oweh OT, Falana MB, Asinmi MR, Yusuf S, Okeme U, Jimoh TZ, Adelagun AA, Moronfolu IA. 2026. Antidiarrheal effects of Vigna subterranea seed extract via modulation of intestinal Na⁺/K⁺-ATPase and antioxidant enzymes. Asian J Nat Prod Biochem 24 (1): f240106. https://doi.org/10.13057/biofar/f240106. In developing countries such as Nigeria, diarrhea remains a major public health concern, and Vigna subterranea is traditionally used to manage it. This study evaluated the antidiarrheal properties of the aqueous seed extract of V. subterranea in male Wistar rats. Quantitative phytochemical analysis revealed the presence of flavonoids (7.07 ± 0.03 mg/g), phenolics (4.87 ± 0.09 mg/g), and steroids (2.24 ± 0.01 mg/g). High-Performance Liquid Chromatography (HPLC) identified 19 constituents, of which quercetin was the predominant flavonol, more abundant and well-established for its biological activity. Oral administration of the extract (100-500 mg/kg) significantly (p < 0.05) reduced fecal weight, defecation frequency, and stool water content in the castor oil-induced diarrheal model. The administration of the extract significantly increased intestinal Na⁺/K⁺-ATPase activity (p < 0.05). In addition, intestinal fluid accumulation (anti-enteropooling effect) and gastrointestinal motility were significantly reduced. The activities of catalase and superoxide dismutase (SOD) were significantly restored (p < 0.05). The antidiarrheal activity of V. subterranea may be linked to improvements in electrolyte transport and antioxidant defense systems. The extract exhibited a notable Antidiarrheal Index (ADI) of 62.81 at 500 mg/kg, demonstrating substantial efficacy, though lower than that of the standard drug loperamide.