Microplastics and Nanoplastics as Potential Metabolic Disruptors: Implications for Insulin Resistance and Type 2 Diabetes.

Human biological matrices such as blood, placenta, lung tissue, and stool have been demonstrated to contain microplastics (MPs) and nanoplastics (NPs), indicating systemic dispersion and long-term environmental exposure. According to novel experimental findings, these xenobiotics may interact with pathways that overlap with the early pathophysiology of insulin resistance and metabolic syndrome, potentially serving as metabolic disruptors. High levels of MP/NP exposure are thought to alter intestinal permeability structurally, which may have an impact on enteroendocrine L-cell environments and the ensuing incretin responses. In animal studies, downstream effects include altered bile acid balance and microbiome remodelling, which is defined by a decrease in taxa that produce short-chain fatty acids (SCFAs). These xenobiotics' portal translocation provides a plausible mechanism for subclinical hepatic inflammation, which may function in tandem with conventional risk factors to disrupt normal metabolic signalling. We consider the translational theory of "MP drainage" as a conceptual approach to lower intestinal particle bioavailability in order to address these theoretical interactions. Nevertheless, its long-term safety, metabolic advantages, and therapeutic effectiveness are yet unknown and require further confirmation. This perspective provides a framework for creating hypotheses that will direct future experimental and epidemiological studies in environmental metabolic toxicity.