Metallic nanoparticles in diabetes mellitus: Mechanistic insights and therapeutic perspectives.

Diabetes mellitus is a chronic metabolic disorder that affects millions worldwide and continues to rise in prevalence. While conventional therapies such as insulin and oral hypoglycemic drugs provide glycemic control, they often fail to address underlying mechanisms like oxidative stress, inflammation, and β-cell dysfunction that drive disease progression. Metallic nanoparticles (MNPs) have emerged as promising multifunctional agents owing to their tunable physicochemical properties, high surface reactivity, and ability to be functionalized for targeted applications. Recent studies demonstrate that nanoparticles such as silver, zinc oxide, gold, titanium dioxide, copper oxide, and iron oxide can enhance insulin secretion and sensitivity, regulate glucose homeostasis, mitigate oxidative stress, and modulate immune and microbial pathways. Application-focused evidence highlights MNPs utility in drug delivery, glucose sensing, localized wound therapy, β-cell preservation/regeneration, and mitigation of diabetic complications (nephropathy, neuropathy, retinopathy). However, clinical momentum remains strongest for localized products and device prototypes, whereas systemic candidates are constrained by biodistribution/clearance, chronic safety requirements, and CMC/GMP reproducibility. Green-synthesized MNPs further offer eco-friendly and biocompatible alternatives, showing synergistic effects with phytochemicals. Despite these advances, translation to clinical practice is still in its infancy due to limited human trials, incomplete pharmacokinetic data, and safety concerns. This review consolidates current mechanistic insights, therapeutic applications, and clinical progress of MNPs in diabetes management, also highlights future research directions for a more translationally disciplined approach. By bridging laboratory research with translational strategies, MNPs hold strong potential to transform the therapeutic landscape of diabetes and its complications.