TY - JOUR T1 - Changes in the gut microbiota composition and the plasma ghrelin level in patients with <em>Helicobacter pylori-</em>infected patients with eradication therapy JF - BMJ Open Gastroenterology DO - 10.1136/bmjgast-2017-000182 VL - 4 IS - 1 SP - e000182 AU - Hidetaka Yanagi AU - Ayumi Tsuda AU - Masashi Matsushima AU - Shunsuke Takahashi AU - Genki Ozawa AU - Yasuhiro Koga AU - Atsushi Takagi Y1 - 2017/11/01 UR - http://bmjopengastro.bmj.com//content/4/1/e000182.abstract N2 - Objective To investigate the influence of antimicrobials on both the gut microbiota structure and the plasma ghrelin level using Helicobacter pylori-infected patients who underwent eradication therapy.Design Twenty H. pylori-infected patients (mean age 68.3 years old) who underwent eradication therapy participated in the study. For the therapy, patients had 1 week of triple therapy consisting of amoxicillin, clarithromycin and proton-pump inhibitors. Stool and blood samples were obtained before (S1), immediately after (S2) and/or 3 months after (S3) the therapies. The concentrations of ghrelin and leptin in the blood were assayed using an ELISA. The V3-V4 region of the 16S rRNA gene was amplified using bacterial DNA from the stool, and about 50 000 high-quality amplicons per sample were grouped into operational taxonomic units for bacteriological analyses.Results The Bacteroidetes:Firmicutes (B:F) ratio was significantly greater at S3 than S1 (P&lt;0.01). This increase in the B:F ratio between S3 and S1 was found in 15 out of 20 patients. A significant decrease in the concentration of active ghrelin (P=0.003) in the plasma was observed between S3 and S1. There was a statistically significant correlation between the rate of patients whose B:F ratio increased and that of patients whose active ghrelin level decreased between S3 and S1 according to Fisher’s exact probability test (P=0.03).Conclusions Changes in the gut microbiota, such as the B:F ratio after treatment with antimicrobials, might cause a change in the plasma ghrelin level, as the direct and earliest target of antimicrobials would be the microbiota rather than the hormone-secreting system. ER -