Fecal Microbiota Transplantation Can Alleviate Gastrointestinal Transit in Rats with High-Fat Diet-Induced Obesity via Regulation of Serotonin Biosynthesis

Abstract

Aim We tested the hypothesis that fecal microbiota transplantation (FMT) could regulate the biotransformation of bile acids, such as deoxycholic acid (DCA) and cholic acid (CA), which in turn regulate the biosynthesis of serotonin in the gut and relieve gastrointestinal dysmotility in high-fat diet- (HFD-) induced obesity in rats. Methods Male Sprague-Dawley rats were randomly divided into the control diet group, HFD group, and HFD-fed with receiving FMT. HFD was fed for 12 weeks. At the end of two-week HFD, FMT was carried out for two weeks. The gastrointestinal transit, serotonin concentration, the expression of tryptophan hydroxylase 1 (TPH1) and serotonin reuptake transporter (SERT), and the levels of bile acids in intestinal contents were examined. Results Compared with the control group, the gastrointestinal transit and small intestinal serotonin concentration of HFD-fed rats were increased. In HFD-fed rats, TPH1 protein expression was increased significantly, while SERT protein expression was decreased, but not significant. The levels of CA and DCA in intestinal contents were also significantly increased in HFD-fed rats compared with the control group. After HFD-fed rats receiving FMT treatment, the gastrointestinal transit, small intestinal serotonin concentration, and TPH1 expression were decreased, while SERT expression was not affected. Moreover, the levels of CA and DCA in intestinal contents were also decreased. Conclusions FMT could alleviate small intestinal transit in the HFD-fed rats by regulating the serotonin biosynthesis. In this process, CA and DCA may be related to the regulation of synthesis of serotonin.

Microbiota, Microbial Metabolites, and Barrier Function in A Patient with Anorexia Nervosa after Fecal Microbiota Transplantation

“…A downward trend was observed in serotonin levels post-FMT in the AN patient’s stool samples (Figure 6B). Similar FMT effects were described in rat intestines on a high-fat diet [46]. Additionally, the decreased expression of tryptophan hydroxylase 1, known as the rate-limiting enzyme in serotonin synthesis, was observed.…”

Skin and Gut Microbiome in Psoriasis: Gaining Insight Into the Pathophysiology of It and Finding Novel Therapeutic Strategies

“…A 36-year-old male patient diagnosed with severe psoriasis for 10 years and IBS for 15 years was subjected to FMT twice via both upper endoscopy and colonoscopy with a 5-week interval. After the second FMT treatment for 5 weeks, the two conditions improved greatly ( Lai et al, 2018 ; Mullish et al, 2018 ; Sun et al, 2018 ; Krajicek et al, 2019 ; Yin et al, 2019 ). Although FMT is potentially effective in many microbiota-related disorders, helping establish trans-kingdom equilibrium between gut fungi, viruses and bacteria to promote the restoration of microbial homeostasis ( McSweeney et al, 2020 ), the effect of FMT depends on several factors, including the bacterial load and microbial composition and function of the recipient and the donor, the physiological and genetic factors related to the recipient and the donor, and FMT preparation and route of administration ( Fischer et al, 2016 ; Vermeire et al, 2016 ; Duvallet et al, 2017 ; Ianiro et al, 2017 ; Allegretti et al, 2019 , 2020 ; Ding et al, 2019 ; Paramsothy et al, 2019 ; Ramai et al, 2019 ; Wilson et al, 2019 ; de Groot et al, 2020 ; McSweeney et al, 2020 ).…”

Effects from diet-induced gut microbiota dysbiosis and obesity can be ameliorated by fecal microbiota transplantation: A multiomics approach

“…This therapy can be an effective approach to obesity treatment [12,13]. Even though FMT has some limitations, several studies have tested its effectiveness and have demonstrated an improvement of some comorbidities associated not only with obesity [14] but also with other noncommunicable diseases [15–18].…”