Slow transit
constipation (STC) has become an epidemic medical problem. There are several kinds of drugs for
constipation; however, each drug has its limitations. The gut microbiota has a close relationship with STC.
Lactulose is an effective drug for
constipation because it is a kind of bulking
laxative and microbioecologic, and it relieves the syndromes of STC. We found that the Chinese Herb Solid Drink (CHSD), which contains medicine food homologous materials such as
psyllium husk, sweetalmond, semen sesami nigrum, and hemp seed, has a similar effect on relieving
constipation as
lactulose, although it has different effects on the gut microbiota. We investigated the mechanisms of CHSD in rats with STC, induced by
diphenoxylate, via
constipation index and
enzyme linked
immunosorbent assay (ELISA) analyses using serum and 16S
rDNA amplicon and gas chromatography-mass spectroscopy (GC-MS). CHSD enhanced the relative abundance of some types of gut microbiota, such as Blautia, Ruminococcus, Roseburia, Coprococcus, Lachnospira, and Phascolarctobacterium, while
lactulose enhanced the relative abundance of Blautia, Phascolarctobacterium, Eubacterium, and Akkernansia in
diphenoxylate-induced STC rats. Both CHSD and
lactulose enhanced the level of
short-chain fatty acids in the faeces of rats; however, the composition of those were different between the two drugs. From the perspective of the gut neuroendocrine system, both CHSD and
lactulose could elevate
neurotransmitters, such as
motilin (MTL) and
substance P (SP), which promote intestinal peristalsis and reduce the expression of
vasoactive intestinal peptide, which inhibits intestinal peristalsis in the serum of STC rats. CHSD could elevate
gastrin expression, which also promoted intestinal peristalsis in serum, while
lactulose did not have this effect. Our findings suggest that CHSD may be an effective and safe therapeutic choice for STC.