Toll-Like Receptors in Diabetes: Immunometabolic Mechanisms and Emerging Precision Therapeutic Strategies

Over the past few years (2020-2025), our understanding of Toll-like receptors (TLRs) in diabetes has evolved significantly, transitioning from their traditional role as innate immune sentinels to central integrators within the immunometabolic hub. Aberrant TLR activation, often triggered by metabolic damage-associated molecular patterns (DAMPs), contributes fundamentally to pancreatic β-cell dysfunction and systemic insulin resistance. To provide a comprehensive synthesis of these developments, we performed a targeted literature search across PubMed and Web of Science, prioritizing high-impact studies published between 2020 and 2025. This review explores the complex, often non-classical, mechanisms driving this pathology, particularly highlighting the emerging "Trojan horse" pathway-an exosomal stealth delivery system wherein gut-derived vesicles covertly transport inflammatory ligands directly into the endosomal compartments of β-cells, bypassing traditional surface receptor surveillance. Furthermore, recent advances in single-cell transcriptomics and Mendelian randomization have unraveled the cellular heterogeneity of the β-cell immune response and established causal genetic links to metaflammation. Building on these mechanistic insights, we propose a preliminary framework for precision medicine that incorporates targeted nanotherapeutic delivery and polygenic risk stratification. Ultimately, we propose that the future management of metabolic diseases must rely not on indiscriminate immunosuppression, but on the careful and precise recalibration of the immunometabolic thermostat.