Trehalose metabolism: an integrative hub linking energy homeostasis and development in insects

Trehalose metabolism in insects represents an evolutionarily conserved metabolic hub regulated by endocrine pathways that couple energy balance to the successful execution and robustness of developmental transition. As the principal circulating sugar in insects, trehalose exhibits unique physicochemical properties that confer both metabolic efficiency and resilience to environmental stress, positioning it as a central currency in insect physiology. Emerging evidence reveals that trehalose metabolism operates as a dynamic interface linking endocrine signaling, nutrient sensing, and developmental transitions. Through coordinated interactions with regulatory hormonal systems such as adipokinetic hormone, insulin-like peptides, juvenile hormone, and ecdysteroids, trehalose metabolism is closely linked to nutrient-sensing pathways, including AMPK, TOR, and FoxO, that collectively shape growth, metamorphosis, and stress tolerance. Perturbations in trehalose metabolic enzymes consistently disrupt developmental homeostasis, leading to defects in molting, reproduction, and survival. Overall, these findings support the view that trehalose is a key energy substrate that plausibly integrates endocrine regulation, nutrient status, and developmental transitions. Emerging evidence suggests that trehalose metabolism may contribute to the metabolic conditions influencing life-history transitions, although further mechanistic studies are needed to establish its signaling functions. By synthesizing recent advances across molecular, physiological, and ecological scales, this review highlights trehalose metabolism as a critical nexus in insect developmental biology and a promising, yet underexploited, target for next-generation pest management strategies.