Impact of maternal microplastic exposure on offspring lung structure and function: Insights into transcriptional misregulation and the TGF-β/α-SMA pathway

The "Developmental Origins of Health and Disease" (DOHaD) theory suggests that prenatal exposure to harmful environmental factors may impair fetal tissue development, increasing the risk of diseases later in life. This study investigated the effects of prenatal exposure to polystyrene microplastics (PS-MPs) on offspring lung development. Pregnant Sprague-Dawley rats were randomly assigned to receive PS-MPs in drinking water until delivery, with a control group receiving standard water. Offspring were assessed at 7 and 120 d after birth without further PS-MPs exposure. Histopathological examination at 7 d revealed PS-MPs deposits, alveolar collapse, and inflammation in lung tissue. Gene expression analysis showed disruptions in tight junctions, transcriptional regulation, and transforming growth factor-beta (TGF-β) pathways. By day 120, lung dysfunction and structural changes, consistent with emphysema were observed. These findings demonstrate that prenatal PS-MPs exposure adversely affects lung development potentially increasing the risk of respiratory diseases. Public health measures should address the potential hazards of microplastics to fetal health.