Zhao Yuning, Chen Hong, Li Wenting, He Qian, Liang Jingyimei, Yan Xiaohai, Yuan Yahong, Yue Tianli
College of Food Science and Engineering, Northwest A&F University, YangLing, Shaanxi, 712100, China; Laboratory of Quality & Safety Risk Assessment for Agro-products (YangLing), Ministry of Agriculture, Yangling, Shaanxi, 712100, China.
College of Food Science and Engineering, Northwest A&F University, YangLing, Shaanxi, 712100, China; Laboratory of Quality & Safety Risk Assessment for Agro-products (YangLing), Ministry of Agriculture, Yangling, Shaanxi, 712100, China.
Int J Biol Macromol. 2022 Jun 1;209(Pt A):356-366. doi: 10.1016/j.ijbiomac.2022.04.028. Epub 2022 Apr 9.
Both tea polysaccharides and selenium have certain remission potential for ulcerative colitis (UC), but few reports focused on natural selenium-containing tea polysaccharides. The purpose of this study was to isolate a selenium-containing tea polysaccharide (ASeTP) and determine its structure and effects on UC. Results showed that ASeTP was primarily composed of three purified, β-pyranoside-linked, protein-binding polysaccharides (SeTP-1, SeTP-2, and SeTP-3) with SeOC, OSeO, and SeO linkages. Specifically, SeTP-1 was a neutral heteropolysaccharide principally composed of mannose, glucose, galactose, xylose, and arabinose, while SeTP-2 and SeTP-3 were acidic heteropolysaccharides due to the existence of glucuronic acid. ASeTP effectively alleviated the symptoms of weight loss, colon shortens, and disease activity index scores increase in dextran sodium sulfate (DSS)-induced colitis mice. ASeTP attenuated the histological damage and maintained the colonic mucosal barrier via up-regulating the expression of occludin, claudin-1, and zona occludens-1 (ZO-1). ASeTP suppressed the levels of pro-inflammatory cytokines and enhanced the antioxidant capacity of colon tissue. Besides, ASeTP beneficially increased the selenium content of the colon. Furthermore, ASeTP remodeled the gut microbiota by accelerating the proliferation of beneficial bacteria and inhibiting pathogenic microorganisms. Thus, ASeTP has the potential to be a functional food against colitis.
茶多糖和硒对溃疡性结肠炎（UC）均具有一定的缓解潜力，但针对天然含硒茶多糖的报道较少。本研究的目的是分离一种含硒茶多糖（ASeTP），并确定其结构以及对UC的影响。结果表明，ASeTP主要由三种纯化的、β-吡喃糖苷连接的、与蛋白质结合的多糖（SeTP-1、SeTP-2和SeTP-3）组成，具有SeOC、OSeO和SeO连接。具体而言，SeTP-1是一种中性杂多糖，主要由甘露糖、葡萄糖、半乳糖、木糖和阿拉伯糖组成，而SeTP-2和SeTP-3由于存在葡萄糖醛酸而属于酸性杂多糖。ASeTP有效缓解了葡聚糖硫酸钠（DSS）诱导的结肠炎小鼠体重减轻、结肠缩短和疾病活动指数评分增加的症状。ASeTP减轻了组织学损伤，并通过上调闭合蛋白、紧密连接蛋白-1和闭合小带蛋白-1（ZO-1）的表达维持结肠黏膜屏障。ASeTP抑制促炎细胞因子水平，增强结肠组织的抗氧化能力。此外，ASeTP有益地增加了结肠中的硒含量。此外，ASeTP通过加速有益细菌的增殖和抑制致病微生物来重塑肠道微生物群。因此，ASeTP有潜力成为一种抗结肠炎的功能性食品。
