Open Access 8 ghrelin level. However, some groups" have found that the test, H. pylori stool antigen test or culturing of biopsy plasma ghrelin concentration decreased in most patients specimens. The exclusion criteria were the patients with 12 weeks after successful H. pylori eradication therapy. gastric cancers and a history of gastrointestinal or hepato- A recent systemic review also reported that the relation- biliary surgery. The demographic data and clinical char- eradication therapy, patients had I week of triple therapy a ship between circulating ghrelin and eradication of H. acteristics of the subjects are summarised in table 1. For pylori is more complex. Recent studies have also suggested that the gut micro- consisting of lansoprazole(0mg twice a day), amox- biota play a fundamental role in the pathophysiology of icillin(750 mg twice daily)and clarithromycin(200mg obesity. Ley et al reported that the ratio of the phylum twice daily). The eradication of H pylori was confirmed by a Bacteroidetes to the phylum Firmicutes(B: F ratio)in the a urea breath test 3 months after the termination of erad- faeces increased when weight was reduced either by a ication therapy. Written informed consent was obtained fat-restricted or carbohydrate-restricted diet in humans, from all of the patients suggesting a critical role of the gut microbiota in the Hormone assay Therefore, in the present study, we investigated the The concentrations of des-acyl ghrelin and active ghrelin 8 influence of antimicrobials on both the gut microbiota in the plasma were assayed using a Desacyl-Ghrelin ELISA structure and the plasma ghrelin level, as we hypothe- Kit (SCETI,Tokyo, Japan) and Active Ghrelin ELISA sised that the change in the ghrelin level after H. pylori Kit(SCETI), respectively. The specific antibodies used eradication therapy was caused by elimination of H. pylori in the former and latter assay kits recognise the C-ter- in the stomach but also by an alteration in the gut micro- minal portion and the octanoyl-modified Ser 3 residue of biota due to antimicrobials ghrelin, respectively. The concentration of leptin in the serum was assayed using Human Leptin RIA Kit(Milli- S pore, Belmopan, Belize) R METHODS Patients Stool sample collection and DNA extraction Patients were defined as positive for H. pyloni infect Stool sample collection from patients was done three if positive results were obtained on aC-urea bi times before(S1), immediately after(S2)and 3months Table 1 Demographic and clinical data of the patients After eradication therapy ID of the patient Ag Gender Endoscopy ofthe stomach Eradication B: F ratio Ghrelin level AG Success Down 2 F Success Down 9Nz<3gN=oosoa3 Success Down AG. RE Down Down AG Failure Success Down 10 AG Success Down AG, HG Success M AG. GU scar Success F Success 15 ccess Down Down AG. DU scar Failure Down AG 18 51 AG Failure Down 19 72 M GU active Success Dowt Success AG, atrophic gastritis; B F, Bacteroidetes: Firmicutes; DU, duodenal ulcer, F, female; GU, gastric ulcer, HG, haemorrhagic gastritis; M, male Yanagi H, et al. BM Open Gastro 2017: 4: 0000182. doi: 10. 1136/bmigast-2017-0001822 Yanagi H, et al. BMJ Open Gastro 2017;4:e000182. doi:10.1136/bmjgast-2017-000182 Open Access ghrelin level.4 However, some groups5 6 have found that the plasma ghrelin concentration decreased in most patients 12 weeks after successful H. pylori eradication therapy. A recent systemic review also reported that the relation￾ship between circulating ghrelin and eradication of H. pylori is more complex.7 Recent studies have also suggested that the gut micro￾biota play a fundamental role in the pathophysiology of obesity.8 Ley et al9 reported that the ratio of the phylum Bacteroidetes to the phylum Firmicutes (B:F ratio) in the faeces increased when weight was reduced either by a fat-restricted or carbohydrate-restricted diet in humans, suggesting a critical role of the gut microbiota in the obesity. Therefore, in the present study, we investigated the influence of antimicrobials on both the gut microbiota structure and the plasma ghrelin level, as we hypothe￾sised that the change in the ghrelin level after H. pylori eradication therapy was caused by elimination of H. pylori in the stomach but also by an alteration in the gut micro￾biota due to antimicrobials. Methods Patients Patients were defined as positive for H. pylori infection if positive results were obtained on a 13C-urea breath test, H. pylori stool antigen test or culturing of biopsy specimens. The exclusion criteria were the patients with gastric cancers and a history of gastrointestinal or hepato￾biliary surgery. The demographic data and clinical char￾acteristics of the subjects are summarised in table 1. For eradication therapy, patients had 1week of triple therapy consisting of lansoprazole (30mg twice a day), amox￾icillin (750mg twice daily) and clarithromycin (200mg twice daily). The eradication of H. pylori was confirmed by a urea breath test 3months after the termination of erad￾ication therapy. Written informed consent was obtained from all of the patients. Hormone assay The concentrations of des-acyl ghrelin and active ghrelin in the plasma were assayed using a Desacyl-Ghrelin ELISA Kit (SCETI, Tokyo, Japan) and Active Ghrelin ELISA Kit (SCETI), respectively. The specific antibodies used in the former and latter assay kits recognise the C-ter￾minal portion and the octanoyl-modified Ser 3 residue of ghrelin, respectively.10 The concentration of leptin in the serum was assayed using Human Leptin RIA Kit (Milli￾pore, Belmopan, Belize). Stool sample collection and DNA extraction Stool sample collection from patients was done three times before (S1), immediately after (S2) and 3months Table 1 Demographic and clinical data of the patients ID of the patient Age Gender Endoscopy ofthe stomach After eradication therapy Eradication B:F ratio Ghrelin level 1 47 F AG Success Down Up 2 66 F AG Success Down Up 3 42 M AG Success Up Down 4 62 F AG Success Up Down 5 73 F AG Success Down Up 6 42 M AG, RE Success Down Down 7 80 M AG Success Up Down 8 42 M AG Failure Up Down 9 76 M AG Success Up Down 10 63 F AG Success Up Down 11 58 F AG, HG Success Up Up 12 78 M AG, GU scar Success Up Down 13 71 F AG Success Up Down 14 65 F AG Success Up Down 15 57 M AG Success Down Down 16 78 F AG, DU scar Failure Up Down 17 74 M AG Success Up Down 18 51 F AG Failure Up Down 19 72 M GU active Success Up Down 20 79 M AG Success Up Down AG, atrophic gastritis; B:F, Bacteroidetes:Firmicutes; DU, duodenal ulcer; F, female; GU, gastric ulcer; HG, haemorrhagic gastritis; M, male; RE, reflux esophagitis. copyright. on 4 July 2018 by guest. 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