Mitochondrial Electron Transport Chain and Redox Systems (ETC)

The mitochondrial electron transport chain (ETC) and associated redox systems comprise a series of protein complexes (Complex I-V) and electron carriers located in the inner mitochondrial membrane. These systems facilitate oxidative phosphorylation, converting energy from nutrients into adenosine triphosphate (ATP) while maintaining cellular redox homeostasis [1]. They play a critical role in disease; mutations or dysfunction are linked to primary mitochondrial disorders, neurodegeneration, and metabolic syndromes, while cancer cells often reprogram these pathways to support rapid proliferation [2]. Pharmacological intervention involves either inhibiting specific complexes to induce cell death in tumors or using redox-active molecules to bypass defects in genetic mitochondrial diseases [3]. For example, Metformin targets Complex I to modulate glucose metabolism, while Atovaquone targets Complex III for its antiparasitic and potential anticancer effects [4]. However, targeting the ETC is challenging due to the risk of systemic toxicity, such as lactic acidosis or impaired energy production in high-demand tissues like the heart and brain [5]. [1] StatPearls: Physiology, Mitochondrial Electron Transport Chain (https://www.ncbi.nlm.nih.gov/books/NBK526040/) [2] Nature Reviews Molecular Cell Biology: Mitochondria in health and disease (https://www.nature.com/articles/nrm3327) [3] Nature Reviews Drug Discovery: Targeting mitochondria for cancer therapy (https://www.nature.com/articles/nrd.2016.58) [4] PubMed: Metformin and the mitochondria (https://pubmed.ncbi.nlm.nih.gov/24571926/) [5] Journal of Clinical Medicine: Drug-Induced Mitochondrial Toxicity (https://www.mdpi.com/2077-0383/9/10/3134)

Other names

Oxidative phosphorylation systemOXPHOSMitochondrial respiratory chainMitochondrial redox network

Inhibition of specific respiratory complexes (I-V) to disrupt ATP production or induce apoptosis, or the use of redox-active carriers to bypass metabolic blocks and reduce oxidative stress.