Loperamide-induced constipation is associated with excessive accumulation of bile acids and cholesterol in the liver of mice; attenuation by hesperidin

Abstract

Loperamide, a widely used antidiarrheal agent, frequently induces constipation alongside other adverse effects. This study explored hesperidin's therapeutic potential in alleviating loperamide-induced constipation and its underlying mechanisms. Constipation models were established in HFD- or NFD-fed mice via loperamide administration (5 mg/kg/day). Hesperidin (100 mg/kg/day) significantly increased fecal weight and moisture in constipated mice. Biochemical analyses revealed elevated cholic acid/chenodeoxycholic acid ratios in serum and liver tissues of loperamide-treated HFD mice, indicating bile acids dysregulation. qRT-PCR and Western blot results demonstrated that hesperidin downregulated hepatic expression of cholesterol/bile acids biosynthesis genes (e.g., Hmgcr, Cyp7a1, Ch25h), which were overexpressed in constipated mice. Concurrently, hesperidin enhanced the expression of transporters (Abcg5, Abcb11, Abcc2) responsible for biliary cholesterol and bile acids efflux. Furthermore, hesperidin upregulated hepatic nuclear receptors (FXR/SHP), key regulators of bile acids homeostasis. Hesperidin alleviates loperamide-induced constipation through two parallel mechanisms: decreasing hepatic cholesterol accumulation and enhancing bile acids excretion. This dual action results from coordinated regulation of biosynthesis enzymes and transport proteins. This study highlights hesperidin's potential as an adjunct therapy to counteract loperamide-related constipation.