Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA.
Department of Animal and Dairy Sciences, University of Wisconsin-Madison, Madison, Wisconsin, USA.
Appl Environ Microbiol. 2024 Aug 21;90(8):e0091524. doi: 10.1128/aem.00915-24. Epub 2024 Jul 10.
Humans and animals encounter a summation of exposures during their lifetime (the exposome). In recent years, the scope of the exposome has begun to include microplastics. Microplastics (MPs) have increasingly been found in locations, including in animal gastrointestinal tracts, where there could be an interaction with Typhimurium, one of the commonly isolated serovars from processed chicken. However, there is limited knowledge on how gut microbiomes are affected by microplastics and if an effect would be exacerbated by the presence of a pathogen. In this study, we aimed to determine if acute exposure to microplastics altered the gut microbiome membership and activity. The microbiota response to a 24 h co-exposure to serovar Typhimurium and/or low-density polyethylene (PE) microplastics in an broiler cecal model was determined using 16S rRNA amplicon sequencing (Illumina) and untargeted metabolomics. Community sequencing results indicated that PE fiber with and without . Typhimurium yielded a lower ratio compared with other treatment groups, which is associated with poor gut health, and overall had greater changes to the cecal microbial community composition. However, changes in the total metabolome were primarily driven by the presence of . Typhimurium. Additionally, the co-exposure to PE fiber and . Typhimurium caused greater cecal microbial community and metabolome changes than either exposure alone. Our results indicate that polymer shape is an important factor in effects resulting from exposure. It also demonstrates that microplastic-pathogen interactions cause metabolic alterations to the chicken cecal microbiome in an chicken cecal mesocosm.
Researching the exposome, a summation of exposure to one's lifespan, will aid in determining the environmental factors that contribute to disease states. There is an emerging concern that microplastic-pathogen interactions in the gastrointestinal tract of broiler chickens may lead to an increase in infection across flocks and eventually increased incidence of human salmonellosis cases. In this research article, we elucidated the effects of acute co-exposure to polyethylene microplastics and serovar Typhimurium on the ceca microbial community . presence caused strong shifts in the cecal metabolome but not the microbiome. The inverse was true for polyethylene fiber. Polyethylene powder had almost no effect. The co-exposure had worse effects than either alone. This demonstrates that exposure effects to the gut microbial community are contaminant-specific. When combined, the interactions between exposures exacerbate changes to the gut environment, necessitating future experiments studying low-dose chronic exposure effects with model systems.
人类和动物在其一生中会接触到各种暴露（暴露组）。近年来，暴露组的范围开始包括微塑料。微塑料（MPs）越来越多地在动物胃肠道等地方被发现，在那里可能会与鼠伤寒沙门氏菌（从加工鸡肉中分离出的常见血清型之一）相互作用。然而，关于肠道微生物组如何受到微塑料的影响，以及如果存在病原体是否会加剧这种影响，人们知之甚少。在这项研究中，我们旨在确定急性暴露于微塑料是否会改变肠道微生物组的成员和活性。使用 16S rRNA 扩增子测序（Illumina）和非靶向代谢组学，确定了在肉鸡盲肠模型中，沙门氏菌血清型和/或低密度聚乙烯（PE）微塑料 24 小时共暴露对微生物群的影响。社区测序结果表明，与其他处理组相比，带有和不带有鼠伤寒沙门氏菌的 PE 纤维的 r 比率较低，这与肠道健康状况不佳有关，并且总体上对盲肠微生物群落组成的变化更大。然而，总代谢组的变化主要由鼠伤寒沙门氏菌的存在驱动。此外，PE 纤维和鼠伤寒沙门氏菌的共暴露比单独暴露更能引起盲肠微生物群落和代谢组的变化。我们的结果表明，聚合物形状是暴露导致的影响的一个重要因素。它还表明，微塑料-病原体相互作用会导致鸡盲肠微生物组的代谢改变在鸡盲肠中。
研究暴露组，即一生中接触的总和，将有助于确定导致疾病状态的环境因素。人们越来越担心，肉鸡胃肠道中微塑料-病原体的相互作用可能会导致禽类感染增加，最终人类沙门氏菌病病例增加。在这篇研究文章中，我们阐明了急性共暴露于聚乙烯微塑料和鼠伤寒沙门氏菌对盲肠微生物群的影响。鼠伤寒沙门氏菌的存在导致盲肠代谢组发生强烈变化，但微生物组没有变化。而聚乙烯纤维则相反。聚乙烯粉末几乎没有影响。共暴露的影响比单独暴露更严重。这表明暴露对肠道微生物群的影响是特定于污染物的。当暴露相互作用时，会加剧肠道环境的变化，因此需要未来使用模型系统研究低剂量慢性暴露影响的实验。
