Abstract：
Visceral and somatic hypersensitivity is a common cause of functional dyspepsia. Marine bioactive components have been revealed to possess numerous valuable abilities. However, as a kind of polysaccharide extracted from brown algae, the study focused on the biological properties of laminarin is still limited, especially in gastrointestinal disorders. In our study, indicators associated with visceral sensational function and gastrointestinal microecology were determined to investigate the modulatory effects of laminarin on functional dyspepsia induced by iodoacetamide. Mice with visceral hypersensitivity were orally administrated with laminarin (50 and 100 mg per kg bw) for fourteen days. The results indicated that laminarin partly alleviated the dysfunction by regulating corticosterone secretion, the expression of 5HT3 receptors at both protein and mRNA levels, and mechanical transduction through the PIEZO2-EPAC1 axis. Furthermore, laminarin administration moderated the imbalanced gut microbial profile, including modulating the abundance of Bacteroidetes and Firmicutes. Our findings revealed that laminarin may restore the overexpression of 5HT3 receptors, the abnormal mechanical transduction, and impaired gut microecology. In conclusion, we provide evidence to support the utilization of laminarin as the ingredient of complementary and alternative medicine of regulating visceral and somatic hypersensitivity.
摘要：
内脏和躯体超敏反应是功能性消化不良的常见原因。海洋生物活性成分已被揭示具有许多有价值的能力。然而,作为一种从褐藻中提取的多糖，目前对海带多糖生物学特性的研究还很有限,尤其是在胃肠道疾病中。在我们的研究中,通过测定与内脏感觉功能和胃肠道微生态相关的指标，研究海带多糖对碘乙酰胺所致功能性消化不良的调节作用。将具有内脏高敏感性的小鼠口服给药海带多糖(50和100mg/kgbw)14天。结果表明，海带多糖通过调节皮质酮的分泌部分减轻了功能障碍，5HT3受体在蛋白质和mRNA水平的表达，和通过PIEZO2-EPAC1轴的机械转导。此外，施用海带多糖缓解了肠道微生物谱的不平衡，包括调节拟杆菌和厚壁菌的丰度。我们的发现表明，海带多糖可以恢复5HT3受体的过度表达，异常的机械转导，和肠道微生态受损。总之,我们提供了证据支持利用海带多糖作为调节内脏和躯体超敏反应的补充和替代药物的成分。
