Effects of lyophilized Korean rice wine (Makgeolli) on intestinal function and bowel activity in loperamide-induced constipation in rats

Constipation is an increasingly common gastrointestinal disorder worldwide. Makgeolli, a traditional Korean rice wine, is celebrated for its rich nutrient content, including probiotics and yeasts, which are known to promote intestinal motility. However, there is limited empirical research on its effects on bowel movements and overall gastrointestinal health. This study aims to explore the impact of Makgeolli on intestinal function and bowel activity using a loperamide-induced constipation model in rats. We divided six-week-old Sprague-Dawley rats into four groups: a normal control (NC), a constipation-induced group (LO, loperamide 4 mg kg^-1), a positive control (L-SP, loperamide + sodium picosulfate 5 mg kg^-1), and a Makgeolli treatment group (L-MG, loperamide + Makgeolli 200 mg kg^-1). After two weeks of treatment, the L-MG group showed significant improvements in fecal parameters and gastrointestinal transit compared to the LO group (p < 0.05). Additionally, DNA damage in colonic cells and fecal water was significantly reduced in the L-MG group (p < 0.05). The activity of harmful intestinal enzymes, such as β-glucosidase, Tryptophanase, Nitroreductase, and β-glucuronidase, was also significantly decreased (p < 0.05). Furthermore, analysis of plasma ORAC levels and lipid peroxides (conjugated dienes) indicated a notable reduction in oxidative stress and lipid peroxidation in the L-MG group (p < 0.05). The mRNA expression levels of pro-inflammatory cytokines (COX-2, INOS, TNF-α) in colon tissue were significantly reduced (p < 0.05). Therefore, Makgeolli shows potential as a functional food that could improve bowel function and facilitate defecation, while also providing antioxidant and anti-inflammatory benefits that may help alleviate constipation.