Protective mechanisms of mitochondria under heat stress: interplay between proteins, minerals, and redox regulation

Abstract

Mitochondria serve as central regulators of cellular energy metabolism and redox homeostasis, yet they are highly susceptible to heat-induced oxidative and proteotoxic stress. Exposure to elevated temperatures disrupts mitochondrial membrane potential, promotes excessive production of reactive oxygen species (ROS), and impairs ATP synthesis, ultimately leading to structural and functional deterioration. This review integrates recent findings on the molecular mechanisms underlying mitochondrial protection during heat stress, focusing on the interplay between stress-responsive proteins, mineral cofactors, and redox signaling. Small heat shock proteins (sHSPs) and molecular chaperones form a primary defense network that prevents protein aggregation and supports proteostasis, while myoglobin, recently identified within mitochondria, contributes to oxygen buffering and respiratory stability. Essential minerals such as magnesium, zinc, selenium, and iron act as key modulators of redox balance and enzymatic activity, maintaining mitochondrial integrity under thermal stress. Furthermore, emerging evidence highlights the integration of mitochondrial and nuclear responses mediated by transcriptional regulators such as HSF1, NRF2, and PGC-1α, ensuring adaptive coordination between metabolic and protective pathways. Comparative physiological data reveal that these mechanisms are evolutionarily conserved across diverse taxa, suggesting a universal mitochondrial defense strategy based on the synergy of chaperone systems and mineral-dependent redox regulation. Understanding these interactions provides valuable insights for enhancing thermotolerance in both biomedical and agricultural contexts.