Lu Yuqing, Xiong Yongjian, Zhang Shuangshuang, Wang Boya, Feng Yuntao, Pu Zhuonan, Wei Kun, Chen Jun, Chen Dapeng, Zhang Peng
Department of Urology, The First Affiliated Hospital of Dalian Medical University, Dalian, China.
Comparative Medicine Department of Researching and Teaching, Dalian Medical University, Dalian, Liaoning, China.
Front Pharmacol. 2024 Nov 1;15:1454713. doi: 10.3389/fphar.2024.1454713. eCollection 2024.
Regulatory T (Treg) cells is required to dampen immune responses against intestinal microbiota, which aid in a healthy body to promise that the resident gut microbiota should not attract the attention of the immune system. Inflammation and inflammatory bowel disease (IBD) can be induced if the immune system fails to ignore the resident gut microbiota and targets them instead. D-mannose, a common monosaccharide in nature, has been shown to ameliorate multiple autoimmune diseases. This study aimed to investigate the therapeutic effect of D-mannose on mice ulcerative colitis (UC) induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS), and elucidate its underlying mechanisms.
To simulate human IBD, we constructed a mouse model of UC by injecting TNBS into the colon.
Our results demonstrated that D-mannose treatment effectively alleviated TNBS-induced UC in mice, as evidenced by the amelioration of UC symptoms. D-mannose treatment significantly reduced inflammation by decreasing the expression of proinflammatory cytokines and inflammation mediators. D-mannose treatment also significantly inhibited oxidative stress, promoted the expression of GSH and SOD, decreased the expression of MDA. Mechanistically, D-mannose upregulated the proportion of both CD4(+) Tregs and CD8(+) Tregs.
In summary, our study provides the first evidence of the therapeutic effect of D-mannose on mice with UC, which is likely mediated by upregulating Treg proportions.
调节性T（Treg）细胞对于抑制针对肠道微生物群的免疫反应是必需的，这有助于健康的身体确保肠道内的常驻微生物群不会引起免疫系统的注意。如果免疫系统未能忽略常驻肠道微生物群并转而攻击它们，就会引发炎症和炎症性肠病（IBD）。D-甘露糖是自然界中常见的单糖，已被证明可改善多种自身免疫性疾病。本研究旨在探讨D-甘露糖对2,4,6-三硝基苯磺酸（TNBS）诱导的小鼠溃疡性结肠炎（UC）的治疗作用，并阐明其潜在机制。
为了模拟人类IBD，我们通过向结肠注射TNBS构建了UC小鼠模型。
我们的结果表明，D-甘露糖治疗有效减轻了TNBS诱导的小鼠UC，UC症状的改善证明了这一点。D-甘露糖治疗通过降低促炎细胞因子和炎症介质的表达显著减轻了炎症。D-甘露糖治疗还显著抑制了氧化应激，促进了谷胱甘肽（GSH）和超氧化物歧化酶（SOD）的表达，降低了丙二醛（MDA）的表达。机制上，D-甘露糖上调了CD4(+) Treg和CD8(+) Treg的比例。
总之，我们的研究首次提供了D-甘露糖对UC小鼠具有治疗作用的证据，这可能是通过上调Treg比例介导的。
