Abstract:
Microplastics, which are tiny plastic particles less than 5 mm in diameter, are widely present in the environment, have become a serious threat to aquatic life and human health, potentially causing ecosystem disorders and health problems. The present study aimed to investigate the effects of microplastics, specifically microplastics-polystyrene (MPs-PS), on the structural integrity, gene expression related to tight junctions, and gut microbiota in mice. A total of 24 Kunming mice aged 30 days were randomly assigned into four groups: control male (CM), control female (CF), PS-exposed male (PSM), and PS-exposed female (PSF)(n = 6). There were significant differences in villus height, width, intestinal surface area, and villus height to crypt depth ratio (V/C) between the PS group and the control group(C) (p <0.05). Gene expression analysis demonstrated the downregulation of Claudin-1, Claudin-2, Claudin-15, and Occludin, in both duodenum and jejunum of the PS group (p < 0.05). Analysis of microbial species using 16S rRNA sequencing indicated decreased diversity in the PSF group, as well as reduced diversity in the PSM group at various taxonomic levels. Beta diversity analysis showed a significant difference in gut microbiota distribution between the PS-exposed and C groups (R2 = 0.113, p<0.01), with this difference being more pronounced among females exposed to MPs-PS. KEGG analysis revealed enrichment of differential microbiota mainly involved in seven signaling pathways, such as nucleotide metabolism(p<0.05). The relative abundance ratio of transcriptional pathways was significantly increased for the PSF group (p<0.01), while excretory system pathways were for PSM group(p<0.05). Overall findings suggest that MPs-PS exhibit a notable sex-dependent impact on mouse gut microbiota, with a stronger effect observed among females; reduced expression of tight junction genes may be associated with dysbiosis, particularly elevated levels of Prevotellaceae.
摘要:
微塑料,是直径小于5毫米的微小塑料颗粒,广泛存在于环境中,已经严重威胁到水生生物和人类健康,可能导致生态系统紊乱和健康问题。本研究旨在研究微塑料的影响,特别是微塑料-聚苯乙烯(MPs-PS),关于结构完整性,与紧密连接相关的基因表达,和小鼠的肠道微生物群。将24只30日龄的昆明种小鼠随机分为四组:对照雄性(CM),对照女性(CF),PS暴露男性(PSM),和PS暴露的女性(PSF)(n=6)。绒毛高度有显著差异,宽度,肠表面积,PS组与对照组的绒毛高度与隐窝深度之比(V/C)(C)(p<0.05)。基因表达分析表明Claudin-1,Claudin-2,Claudin-15和Occludin的下调,PS组的十二指肠和空肠(p<0.05)。使用16SrRNA测序分析微生物物种表明PSF组的多样性降低,以及PSM组在各种分类水平上的多样性减少。β多样性分析表明,PS暴露组和C组之间的肠道菌群分布存在显着差异(R2=0.113,p<0.01),这种差异在暴露于MP-PS的女性中更为明显。KEGG分析显示,差异微生物群的富集主要涉及七个信号通路,如核苷酸代谢(p<0.05)。PSF组转录通路的相对丰度比显著增加(p<0.01),而排泄系统途径为PSM组(p<0.05)。总体研究结果表明,MPs-PS对小鼠肠道微生物群表现出显著的性别依赖性影响,在女性中观察到更强的效果;紧密连接基因的表达降低可能与菌群失调有关,特别是Prevotellaceae的水平升高。