Dendrobium huoshanense polysaccharide regionally regulates intestinal mucosal barrier function and intestinal microbiota in mice.
Xie Song-Zi,Liu Bing,Ye Hui-Yu,Li Qiang-Ming,Pan Li-Hua,Zha Xue-Qiang,Liu Jian,Duan Jun,Luo Jian-Ping
The present study investigated the effects of a homogeneous Dendrobium huoshanense polysaccharide (GXG) on mucosal barrier function and microbiota composition in different intestinal regions of mice. Results exhibited, besides changing the intestinal physiological status, orally administrated GXG could improve the intestinal physical barrier function by modulating mucosal structures and up-regulating the expression of tight junction proteins, reinforce the intestinal biochemical barrier function by elevating the expression and secretion of mucin-2, β-defensins and sIgA, and regulate the intestinal immunological barrier function by stimulating the production of cytokines and the functional development of immune cells. Simultaneously, GXG could differentially impact the composition and metabolism of microbiota along intestinal tract. In addition, the immune response in spleen and peripheral blood were effectively regulated by GXG. These results indicated that GXG might be used as functional agent to improve host health.
Effects induced by polyethylene microplastics oral exposure on colon mucin release, inflammation, gut microflora composition and metabolism in mice.
Sun Hanqing,Chen Na,Yang Xiaona,Xia Yankai,Wu Di
Ecotoxicology and environmental safety
Microplastics are plastic fragments widely distributed in the environment and accumulate in the organisms. However, the research on microplastics effects in mammals is limited. Polyethylene is the main kind of microplastics in the environment. We hypothesized that polyethylene exposure disrupts host intestine metabolism by modifying intestine microflora composition and then lipopolysaccharide (LPS) pathway. Female mice were orally exposed to 0, 0.002 and 0.2 μg/g/d polyethylene microplastics (PE MPs) for 30 days. Colon mucin density was quantized after AB-PAS staining. Mucin 2 (MUC2), inflammatory factors (IL-1β, IL-6, IL-8 and IL-10), short-chain fatty acid receptors (GPR41 and GPR43), LPS receptors (TLR4 and MyD88) and LPS pathway downstream genes (ERK1 and NF-κB) mRNA levels in colon were measured. Feces were collected on the 15th day of exposure for gut microflora analysis. Blood biochemical analysis was performed. Results showed that 0.2 μg/g/d PE MPs exposure significantly decreased colon mucin expression (p < 0.05), decreased IL-1β (p < 0.05) and increased IL-8 and IL-10 levels (p < 0.01 and p < 0.001 respectively). Microflora data showed that in 0.2 μg/g/d PE MPs group the number of Firmicutes decreased and the number of Bacteroides increased (both p < 0.01). Predicted KEGG metabolic pathways by piecrust method indicated that PE MPs enhanced amino acids metabolism in microflora. ERK1 and NF-κB mRNA were significantly lower in 0.2 μg/g/d PE MPs group (both p < 0.001). Blood total protein, albumin and globulin levels significantly increased after 0.2 μg/g/d PE MPs exposure (p < 0.01, p < 0.01 and p < 0.05 respectively). These results indicate that PE MPs exposure induced decreased mucin production, a slight immune response and increased the microflora amino acid metabolism in the mice colon by modifying colon microflora composition. SUMMARY: Polyethylene microplastics exposure decreased colon mucin release and increased amino acid metabolism by modifying colon microflora composition.