Takagi Tomohisa, Naito Yuji, Higashimura Yasuki, Ushiroda Chihiro, Mizushima Katsura, Ohashi Yuji, Yasukawa Zenta, Ozeki Makoto, Tokunaga Makoto, Okubo Tsutomu, Katada Kazuhiro, Kamada Kazuhiro, Uchiyama Kazuhiko, Handa Osamu, Itoh Yoshito, Yoshikawa Toshikazu
1Department of Molecular Gastroenterology and Hepatology,Graduate School of Medical Science,Kyoto Prefectural University of Medicine,Kyoto,602-8566,Japan.
2Laboratory of Food Hygiene,Department of Food Science and Technology,Nippon Veterinary and Life Science University,1-7-1, Kyonan-cho,Musashino,Tokyo 180-8602,Japan.
Br J Nutr. 2016 Oct;116(7):1199-1205. doi: 10.1017/S0007114516003068. Epub 2016 Sep 8.
Partially hydrolysed guar gum (PHGG), a water-soluble dietary fibre produced by the controlled partial enzymatic hydrolysis of guar gum beans, has various physiological roles. This study aimed to elucidate the beneficial effects of PHGG on colonic mucosal damage in a murine 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis model. Acute colitis was induced in male C57BL/6 mice with TNBS after 2 weeks of pre-feeding with PHGG (5 %). The colonic mucosal inflammation was evaluated using macroscopic damage scores, and neutrophil infiltration was assessed by measuring tissue-associated myeloperoxidase (MPO) activity in the colonic mucosa. TNF-α expression in the colonic mucosa was measured by ELISA and real-time PCR. Moreover, the intestinal microbiota and production of SCFA were assessed by real-time PCR and HPLC, respectively. Colonic damage due to TNBS administration was significantly ameliorated by PHGG treatment. Furthermore, PHGG significantly inhibited increases in MPO activity and TNF-α protein and mRNA expression in the colonic mucosa in TNBS-induced colitis. On analysis of intestinal microbiota, we found that the concentration of the Clostridium coccoides group (Clostridium cluster XIVa), the Clostridium leptum subgroup (Clostridium cluster IV) and the Bacteroides fragilis group had significantly increased in PHGG-fed mice. On analysis of SCFA, we found that the caecal content of acetic acid, propionic acid and butyric acid had significantly increased in PHGG-fed mice. Together, these results suggest that chronic ingestion of PHGG prevents the development of TNBS-induced colitis in mice by modulating the intestinal microbiota and SCFA, which may be significant in the development of therapeutics for inflammatory bowel disease.
部分水解瓜尔胶（PHGG）是通过对瓜尔胶豆进行可控的部分酶促水解而产生的一种水溶性膳食纤维，具有多种生理作用。本研究旨在阐明PHGG对小鼠2,4,6-三硝基苯磺酸（TNBS）诱导的结肠炎模型中结肠黏膜损伤的有益作用。在雄性C57BL/6小鼠中，用PHGG（5%）预饲2周后，再用TNBS诱导急性结肠炎。使用宏观损伤评分评估结肠黏膜炎症，并通过测量结肠黏膜中与组织相关的髓过氧化物酶（MPO）活性来评估中性粒细胞浸润。通过酶联免疫吸附测定法（ELISA）和实时聚合酶链反应（PCR）测量结肠黏膜中肿瘤坏死因子-α（TNF-α）的表达。此外，分别通过实时PCR和高效液相色谱法（HPLC）评估肠道微生物群和短链脂肪酸（SCFA）的产生。PHGG治疗可显著改善因TNBS给药导致的结肠损伤。此外，PHGG显著抑制TNBS诱导的结肠炎小鼠结肠黏膜中MPO活性以及TNF-α蛋白和mRNA表达的增加。在分析肠道微生物群时，我们发现，在喂食PHGG的小鼠中，球菌状梭菌属（梭菌属第十四簇）、纤细梭菌亚群（梭菌属第四簇）和脆弱拟杆菌群的浓度显著增加。在分析SCFA时，我们发现，喂食PHGG的小鼠盲肠内容物中乙酸、丙酸和丁酸的含量显著增加。总之，这些结果表明，长期摄入PHGG可通过调节肠道微生物群和SCFA来预防小鼠TNBS诱导的结肠炎的发生，这在炎症性肠病治疗药物的开发中可能具有重要意义。
