Changes in fecal short‐chain fatty acids following fecal microbiota transplantation in patients with irritable bowel syndrome

Abstract

Background Short‐chain fatty acids (SCFAs) may play a role in the pathophysiology of irritable bowel syndrome (IBS). This study analyzed fecal SCFAs after performing fecal microbiota transplantation (FMT) in the IBS patients who were included in our previous study of the efficacy of FMT. Methods This study included 142 of the 164 IBS patients who participated in our previous study. They were belonging to three groups: placebo (own feces), 30‐g (superdonor feces), and 60‐g (superdonor feces) FMT. The patients completed the IBS Severity Scoring System (IBS‐SSS) Birmingham IBS Symptom, Fatigue Assessment Scale (FAS), the IBS Quality of Life (IBS‐QoL) and Short‐Form Nepean Dyspepsia Index (SF‐NDI) questionnaires and delivered fecal samples at the baseline and 1 month after FMT. The SCFA levels were determined by vacuum distillation followed by gas chromatography. Key Results The fecal butyric acid level was significantly increased after FMT in both the 30‐g and 60‐g groups (both P ≤ 0.001). In the 60‐g group, the levels of total SCFAs and isobutyric, isovaleric, and valeric acids increased after FMT. Butyric acid levels in the responders in both the 30‐g and 60‐g FMT groups were significantly inversely correlated with IBS‐SSS and FAS scores (P = 0.001, r = −0.3 and P = 0.0001. r=‐ 0.3, respectively). There were no differences in the SCFA levels in the placebo group after FMT. Conclusion and Inferences FMT increases the fecal SCFA levels in IBS patients. The increase in the butyric acid level is inversely correlated with symptoms in IBS patients following FMT, suggesting that SCFAs might play a role in the pathophysiology of IBS. http://www.clinicaltrials.gov (NCT03822299).

Responses to faecal microbiota transplantation in female and male patients with irritable bowel syndrome

“…PYY is a mediator of the ileal brake and stimulates the absorption of water and electrolytes in the colon[ 37 ]. The faecal level of total SCFAs increased significantly in IBS patients after 1 mo and remained elevated at 1 year after FMT (unpublished data)[ 25 ]. Similarly, the faecal level of butyric acid increased in IBS patients after 1 mo and remained elevated at 1 year after FMT (unpublished data)[ 25 ].…”

“…The faecal level of total SCFAs increased significantly in IBS patients after 1 mo and remained elevated at 1 year after FMT (unpublished data)[ 25 ]. Similarly, the faecal level of butyric acid increased in IBS patients after 1 mo and remained elevated at 1 year after FMT (unpublished data)[ 25 ]. Butyrate is a major energy source for colonic epithelial cells, interacts with the immune response, modulates the oxidative stress, and decreases both intestinal-cell permeability and intestinal motility[ 41 ].…”

“…The method used to determine faecal SCFA levels has been described in detail previously[ 25 ]. Briefly, the faecal samples were homogenized with a solution containing 3 mmol/L 2-ethylbutyric acid and 0.5 mmol/L H 2 SO 4 .…”

“…A recent RCT of IBS patients performed by our group found that FMT led to marked reductions in IBS symptoms and fatigue and an improvement in the quality of life[ 12 ]. These improvements were accompanied by marked changes in the faecal bacteria profile and the profile of short-chain fatty acids (SCFAs) of the patients[ 12 , 25 ].…”

Fecal microbiota transplantation for irritable bowel syndrome: An intervention for the 21st century

“…In the RCT of El-Salhy et al [ 11 , 55 ] in which FMT was most effective, the severity of dysbiosis did not differ significantly between the placebo and active treated groups after 1 mo, but it was reduced significantly after 1 year. One month after FMT, the bacterial profile changed significantly in the active treated groups compared with the placebo group (Figure 7 )[ 11 ].…”