Arecoline alleviated loperamide induced constipation by regulating gut microbes and the expression of colonic genome.

This study aimed to investigate the effects of arecoline on constipation by intervening at different times to explore its preventive and therapeutic effects. Symptoms related to constipation, gut microbes, short-chain fatty acid (SCFA) content in the cecum, and gene expression in the colon were measured to examine the effect of arecoline on relieving constipation. The results showed that arecoline intervention alleviated loperamide-induced constipation, as evidenced by significantly shortened intestinal transit time, increased fecal water content, improved small bowel propulsion, and increased defecation frequency. In addition, arecoline significantly reduced the levels of gastrointestinal regulatory peptides such as somatostatin and vasoactive intestinal peptide in the serum, thereby regulating intestinal peristalsis. Histopathological analysis showed that arecoline ameliorated intestinal injury caused by constipation. Gut microbial analysis indicated that arecoline altered the taxonomic composition and levels of its metabolite SCFAs in the gut microbiota. Furthermore, the colonic transcriptome results indicated that genes expression related to intestinal diseases were significantly down-regulated by arecoline intervention. In conclusion, the results of the correlation analysis propose a possible mechanism of arecoline in alleviating constipation by modulating the gut microbes and their metabolites and regulating the gut genome.

Short-term arecoline exposure affected the systemic health state of mice, in which gut microbes played an important role.

Arecoline is a critical bioactive component in areca nuts with toxicity and pharmacological activities. However, its effects on body health remain unclear. Here, we investigated the effects of arecoline on physiologic and biochemical parameters in mouse serum, liver, brain, and intestine. The effect of arecoline on gut microbiota was investigated based on shotgun metagenomic sequencing. The results showed that arecoline promoted lipid metabolism in mice, manifested as significantly reduced serum TC and TG and liver TC levels and a reduction in abdominal fat accumulation. Arecoline intake significantly modulated the neurotransmitters 5-HT and NE levels in the brain. Notably, arecoline intervention significantly increased serum IL-6 and LPS levels, leading to inflammation in the body. High-dose arecoline significantly reduced liver GSH levels and increased MDA levels, which led to oxidative stress in the liver. Arecoline intake promoted the release of intestinal IL-6 and IL-1ß, causing intestinal injury. In addition, we observed a significant response of gut microbiota to arecoline intake, reflecting significant changes in diversity and function of the gut microbes. Further mechanistic exploration suggested that arecoline intake can regulate gut microbes and ultimately affect the host's health. This study provided technical help for the pharmacochemical application and toxicity control of arecoline.