Comprehensive Roles of ZIP and ZnT Zinc Transporters in Metabolic Inflammation

Zinc homeostasis is fundamental to metabolic health, orchestrated by the coordinated actions of two major zinc transporter families: ZIP (Zrt- and Irt-like proteins) and ZnT (zinc transporters). ZIP transporters facilitate zinc influx into the cytosol from the extracellular space or from the lumen of intracellular organelles, whereas ZnT transporters control zinc efflux from the cytosol to the extracellular space or facilitate its sequestration into intracellular vesicles and organelles, concurrently harboring the meticulous intracellular zinc homeostasis. This equilibrium is essential for all critical functions like cellular response, metabolic control, and immune pathway alteration. Disruption of this homeostasis is a driver of different pathological alterations like metabolic inflammation, a chronic low-grade inflammatory state underlying obesity; type 2 diabetes; and nonalcoholic fatty liver disease. Recent studies revealed that ZIP and ZnT transporters dynamically regulate metabolic and inflammatory cues, with their tissue-specific expression varying by tissue and acclimating to different physiological and pathological conditions. Recent advanced research in molecular and genetic understanding has helped to deepen our knowledge of the interplay of activity between ZIP and ZnT transporters and their crosstalk in metabolic tissues, underscoring the potential therapeutic prospect for restoring zinc balance and ameliorating metabolic inflammation. This review provides a comprehensive overview that covers the function, regulation, and interactive crosstalk of ZIP and ZnT zinc transporters in metabolic tissues and their pathological conditions.