Liu Bo, Liu Qing-Mei, Li Gui-Ling, Sun Le-Chang, Gao Yuan-Yuan, Zhang Ya-Fen, Liu Hong, Cao Min-Jie, Liu Guang-Ming
College of Food and Biological Engineering, Xiamen Key Laboratory of Marine Functional Food, Fujian Provincial Engineering Technology Research Center of Marine Functional Food, Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Jimei University 43 Yindou Road Xiamen 361021 Fujian P. R. China
RSC Adv. 2019 Jan 18;9(5):2360-2370. doi: 10.1039/c8ra09247h.
Polysaccharides from red algae and possess various bioactive functions, however, their anti-diarrhea activity remains incompletely defined. In the current study, sulphated polysaccharides were extracted by high pressure treatment plus ethanol precipitation from these two algae, and named PHSP and GLSP, respectively. PHSP and GLSP showed decreased viscosity and molecular weight. Meanwhile, they have a certain immunomodulatory effect on wound healing and migration of RAW264.7 cells. Moreover, they significantly increased the secretion of pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). A BALB/c model infected by enterotoxigenic (ETEC)-K88 was also established to evaluate the anti-diarrhea activity of PHSP and GLSP. The results showed that PHSP and GLSP were able to alleviate mice diarrhea symptoms. Meanwhile, they inhibited the release of pro-inflammatory cytokines and suppressed the secretion of immunoglobulin A reducing the population of B cells. In addition, the nitroblue tetrazolium levels of mouse serum were decreased. Taken together, PHSP and GLSP alleviated the inflammatory response of ETEC-K88-induced diarrhea through both specific and non-specific immunity. Sulphated polysaccharides from red algae may be used as functional food components for remitting diarrhea.
红藻多糖具有多种生物活性功能，然而，它们的抗腹泻活性仍未完全明确。在本研究中，通过高压处理加乙醇沉淀从这两种藻类中提取了硫酸化多糖，分别命名为PHSP和GLSP。PHSP和GLSP的粘度和分子量均降低。同时，它们对RAW264.7细胞的伤口愈合和迁移具有一定的免疫调节作用。此外，它们显著增加了促炎细胞因子肿瘤坏死因子-α（TNF-α）和白细胞介素-6（IL-6）的分泌。还建立了产肠毒素大肠杆菌（ETEC）-K88感染的BALB/c模型来评估PHSP和GLSP的抗腹泻活性。结果表明，PHSP和GLSP能够减轻小鼠腹泻症状。同时，它们抑制促炎细胞因子的释放，抑制免疫球蛋白A的分泌，减少B细胞数量。此外，小鼠血清的硝基蓝四氮唑水平降低。综上所述，PHSP和GLSP通过特异性和非特异性免疫减轻了ETEC-K88诱导的腹泻的炎症反应。红藻中的硫酸化多糖可作为缓解腹泻的功能性食品成分。
