Mitochondrial NAD(P)(+) Transhydrogenase: From Molecular Features to Physiology and Disease

Author(s)

Francisco, Annelise ^[1] ; Figueira, Tiago Rezende ^[2] ; Castilho, Roger Frigerio ^[1]

Affiliation

^[1] Univ Estadual Campinas, Fac Med Sci, Dept Pathol, UNICAMP, BR-13083887 Campinas, SP - Brazil

^[2] Univ Sao Paulo, Sch Phys Educ & Sport Ribeirao Preto, Ribeirao Preto - Brazil

• Document type: Journal article
• Source: Antioxidants & Redox Signaling; AUG 2021.
• Web of Science Citations: 0

Abstract

Significance: Proton-translocating NAD(P)(+) transhydrogenase, also known as nicotinamide nucleotide transhydrogenase (NNT), catalyzes a reversible reaction coupling the protonmotive force across the inner mitochondrial membrane and hydride (H-, a proton plus two electrons) transfer between the mitochondrial pools of NAD(H) and NADP(H). The forward NNT reaction is a source of NADPH in the mitochondrial matrix, fueling antioxidant and biosynthetic pathways with reductive potential. Despite the greater emphasis given to the net forward reaction, the reverse NNT reaction that oxidizes NADPH also occurs in physiological and pathological conditions. Recent Advances: NNT (dys)function has been linked to various metabolic pathways and disease phenotypes. Most of these findings have been based on spontaneous loss-of-function Nnt mutations found in the C57BL/6J mouse strain (Nnt(C57BL/6J) mutation) and disease-causing Nnt mutations in humans. The present review focuses on recent advances based on the mouse Nnt(C57BL/6J) mutation. Critical Issues: Most studies associating NNT function with disease phenotypes have been based on comparisons between different strains of inbred mice (with or without the Nnt(C57BL/6J) mutation), which creates uncertainties over the actual contribution of NNT in the context of other potential genetic modifiers. Future Directions: Future research might contribute to understanding the role of NNT in pathological conditions and elucidate how NNT regulates physiological signaling through its forward and reverse reactions. The importance of NNT in redox balance and tumor cell proliferation makes it a potential target of new therapeutic strategies for oxidative-stress-mediated diseases and cancer. (AU)

• FAPESP's process: 17/17728-8 - Mitochondrial function and dysfunction: implications for aging and associated diseases
• Grantee: Aníbal Eugênio Vercesi
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 20/05202-4 - The role of mitochondrial NAD(P)+ transhydrogenase in monoaminergic neurotransmission and neurodegeneration in mice
• Grantee: Annelise Francisco
• Support Opportunities: Scholarships in Brazil - Post-Doctoral