Hubei Key Laboratory of Animal Nutrition and Feed Science, Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Wuhan Polytechnic University, Wuhan 430023, China.
Food Funct. 2019 Jan 22;10(1):479-489. doi: 10.1039/c8fo02438c.
The intestinal microbiota plays a vital role in metabolism, pathogen resistance, and immune development in host cells, and is modifiable by dietary change. Lentinan (LNT), a type of mushroom polysaccharide, is known to ameliorate intestinal inflammation with the potential of therapeutic effect on digestive diseases. We hypothesized that LNT could alleviate Escherichia coli lipopolysaccharide (LPS)-induced intestinal injury via regulating the composition and metabolites of intestinal microbiota in a piglet model. Twenty-four weaned piglets were used in a 2 × 2 factorial design, and the main factors included a dietary treatment (basal or LNT diet) and immunological challenge (LPS or saline). After feeding basal or LNT diet for 21 days, pigs were injected with LPS or saline. At 4 h post-injection, pigs were killed and jejunum, ileum and cecal digesta were collected. LNT improved intestinal morphology and barrier function. LNT also inhibited inflammatory signaling pathways (toll-like receptor 4 and nucleotide binding oligomerization domain protein) and pro-inflammatory cytokines (tumor necrosis factor-α, interleukin-1β and interleukin-6) expression, as well as up-regulated the heat shock protein 70 expression in small intestine. In addition, LNT enhanced the concentrations of propionate, butyrate, isobutyrate and isovalerate in cecal digesta, resulting in a significant increase in histone acetylation without affecting the protein level of G protein-coupled receptor 41 (GPR41), a short chain fatty acid receptor. Bacterial 16S rRNA gene pyrosequencing showed that LNT had a great impact on gut microbiota composition at different taxonomic levels. Moreover, the correlation analysis revealed some potential relationships between cecal metabolites and certain intestinal microbiota. These results indicate that LNT promotes intestinal health, in part, through altering intestinal microbiota composition and increasing the short chain fatty acid synthesis, which subsequently lead to a reduction in inflammation and hyper-acetylation of histones.
肠道微生物群在宿主细胞的代谢、病原体抗性和免疫发育中发挥着至关重要的作用，并且可以通过饮食改变来调节。香菇多糖（LNT）是一种蘑菇多糖，已知可改善肠道炎症，并有治疗消化疾病的潜在疗效。我们假设 LNT 可以通过调节仔猪模型中肠道微生物群的组成和代谢物来缓解大肠杆菌脂多糖（LPS）诱导的肠道损伤。在 2×2 析因设计中使用了 24 头断奶仔猪，主要因素包括饮食处理（基础或 LNT 饮食）和免疫挑战（LPS 或盐水）。在饲喂基础或 LNT 饮食 21 天后，猪被注射 LPS 或盐水。注射后 4 小时，处死猪并收集空肠、回肠和盲肠内容物。LNT 改善了肠道形态和屏障功能。LNT 还抑制了炎症信号通路（Toll 样受体 4 和核苷酸结合寡聚化结构域蛋白）和促炎细胞因子（肿瘤坏死因子-α、白细胞介素-1β 和白细胞介素-6）的表达，并上调了小肠中的热休克蛋白 70 表达。此外，LNT 增强了盲肠内容物中丙酸、丁酸、异丁酸和异戊酸的浓度，导致组蛋白乙酰化显著增加，而不影响短链脂肪酸受体 G 蛋白偶联受体 41（GPR41）的蛋白水平。细菌 16S rRNA 基因焦磷酸测序显示，LNT 对不同分类水平的肠道微生物群组成有很大影响。此外，相关分析显示盲肠代谢物与某些肠道微生物群之间存在一些潜在关系。这些结果表明，LNT 通过改变肠道微生物群组成和增加短链脂肪酸合成来促进肠道健康，从而减少炎症和组蛋白的过度乙酰化。
