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Microplastics (MPs) are an emerging environmental issue due to their accumulation in ecosystems and living organisms. Increasing evidence shows that MPs impact vascular function, with recent studies finding MPs in atheromas linked to cardiovascular events. Since vascular smooth muscle cells (VSMCs) are crucial to maintaining vascular function, this study examined how MPs activate VSMCs, leading to cardiovascular diseases like atherosclerosis and vascular calcification. The study used polyethylene (PE) and polystyrene (PS), common in food packaging, as "virgin" or photo-degraded to simulate environmental conditions. VSMC viability, apoptosis, cytotoxicity, inflammation, and activation markers were evaluated. PE and PS affected VSMC viability, induced apoptosis, and triggered pathological changes such as altered migration and proliferation. Key markers like RUNX-2 and galectin-3, which regulate cardiovascular pathology, were activated, alongside the inflammasome complex. In conclusion, MPs can induce harmful activation of VSMCs, posing potential health risks through inflammation, cell damage, and phenotypic changes. Understanding these toxic mechanisms may reveal critical pathways for intervention and prevention. [ABSTRACT FROM AUTHOR]

Aim: In the present study, we investigated the involvement of NLRP3 inflammasome in the intestinal epithelial barrier (IEB) changes associated with obesity, and its role in the interplay between enteric glia and intestinal epithelial cells (IECs). Methods: Wild‐type C57BL/6J and NLRP3‐KO (−/−) mice were fed with high‐fat diet (HFD) or standard diet for 8 weeks. Colonic IEB integrity and inflammasome activation were assessed. Immunolocalization of colonic mucosal GFAP‐ and NLRP3‐positive cells along with in vitro coculture experiments with enteric glial cells (EGCs) and IECs allowed to investigate the potential link between altered IEB, enteric gliosis, and NLRP3 activation. Results: HFD mice showed increased body weight, altered IEB integrity, increased GFAP‐positive glial cells, and NLRP3 inflammasome hyperactivation. HFD‐NLRP3−/− mice showed a lower increase in body weight, an improvement in IEB integrity and an absence of enteric gliosis. Coculture experiments showed that palmitate and lipopolysaccharide contribute to IEB damage and promote enteric gliosis with consequent hyperactivation of enteric glial NLRP3/caspase‐1/IL‐1β signaling. Enteric glial‐derived IL‐1β release exacerbates the IEB alterations. Such an effect was abrogated upon incubation with anakinra (IL‐1β receptor antagonist) and with conditioned medium derived from silenced‐NLRP3 glial cells. Conclusion: HFD intake elicits mucosal enteric gliotic processes characterized by a hyperactivation of NLRP3/caspase‐1/IL‐1β signaling pathway, that contributes to further exacerbate the disruption of intestinal mucosal barrier integrity. However, we cannot rule out the contribution of NLRP3 inflammasome activation from other cells, such as immune cells, in IEB alterations associated with obesity. Overall, our results suggest that enteric glial NLRP3 inflammasome might represent an interesting molecular target for the development of novel pharmacological approaches aimed at managing the enteric inflammation and intestinal mucosal dysfunctions associated with obesity. [ABSTRACT FROM AUTHOR]