Microplastic exposure disturbs sleep structure, reduces lifespan, and decreases ovary size in <i>Drosophila</i> <i>melanogaster</i>
Wei Yan, 中国科学院深圳先进技术研究院深港脑科学创新研究院, 广东 深圳 518000, 中国, Zijie Li, Zi-Yi Lin, Shuqin Ji, William Ka Fai Tse, Zhiqiang Meng, Chang Liu, Lei Li, 中国科学院深圳先进技术研究院脑认知与脑疾病研究所中国科学院脑联结解析与调控重点实验室, 广东 深圳 518000, 中国, 九州大学农学院国际教育与研究推广中心, 发育障碍与毒理学实验室, 福冈 819-0395, 日本, 中国科学院深圳先进技术研究院脑认知与脑疾病研究所深圳市药物成瘾重点实验室, 广东 深圳 518000, 中国, 中国科学院深圳先进技术研究院脑认知与脑疾病研究所广东省脑连接图谱重点实验室, 广东 深圳 518000, 中国
Abstract
The organ-specific toxicity resulting from microplastic (MP) exposure has been extensively explored, particularly concerning the gut, liver, testis, and lung. However, under natural conditions, these effects are not restricted to specific organs or tissues. Investigating whether MP exposure presents a systemic threat to an entire organism, impacting factors such as lifespan, sleep, and fecundity, is essential. In this study, we investigated the effects of dietary exposure to two different doses of MPs (1–5 μm) using the terrestrial model organism <italic>Drosophila melanogaster</italic>. Results indicated that the particles caused gut damage and remained within the digestive system. Continuous MP exposure significantly shortened the lifespan of adult flies. Even short-term exposure disrupted sleep patterns, increasing the length of daytime sleep episodes. Additionally, one week of MP exposure reduced ovary size, with a trend towards decreased egg-laying in mated females. Although MPs did not penetrate the brain or ovaries, transcriptome analysis revealed altered gene expression in these tissues. In the ovary, Gene Ontology (GO) analysis indicated genotoxic effects impacting inflammation, circadian regulation, and metabolic processes, with significant impacts on extracellular structure-related pathways. In the brain, GO analysis identified changes in pathways associated with proteolysis and carbohydrate metabolism. Overall, this study provides compelling evidence of the systemic negative effects of MP exposure, highlighting the urgent need to address and mitigate environmental MP pollution.