Classical famous prescription of Jichuan decoction improved loperamide-induced slow transit constipation in rats through the cAMP/PKA/AQPs signaling pathway and maintained inflammatory/intestinal flora homeostasis

Introduction: Jichuan decoction (JCD) is a well-known traditional Chinese medicinal formula that moistens the intestines and is widely used for the treatment of constipation in China. However, its effects and mechanisms in alleviating slow transit constipation (STC) in vivo remain unclear. We attempted to demonstrate the effect of JCD, with and without essential oil (VO), on intestinal transit and its underlying molecular mechanisms in rats with loperamide-induced STC. Materials and methods: Water consumption, body weight, fecal water content, time to first melena excretion, and intestinal transit ratio of the animals were measured. 5-Hydroxytryptamine (5-HT), substance P (SP), vasoactive intestinal peptide (VIP), and interleukin-6 (IL-6) levels in the sera of rats were evaluated using ELISA. Hematoxylin and eosin and Periodic Acid-Schiff staining were used to determine intestinal tissue histology, while quantitative real-time PCR, western blotting, and immunohistochemical analysis were used to assess the relative expression levels of cAMP/PKA/AQPs pathway- and inflammation-related proteins. 16 S rDNA sequence analysis of rat feces was used to determine the diversity and abundance of the intestinal flora. Results: , with the JCD + VO groups showing better therapeutic outcomes. Conclusion: JCD improved loperamide-induced STC, and co-administration with VO exhibited better activity than sole JCD therapy. JCD may improve STC by inhibiting the cAMP/PKA/AQPs signaling pathway and maintaining inflammatory/intestinal flora homeostasis.