Bioenergetics: Open Access

Control of Mitochondrial Respiration

Erich Gnaiger^* Department of Exercise and Sport Science, Human Performance Lab, University of Wisconsin â?? La Cros, USA
^*Correspondence: Erich Gnaiger, Department of Exercise and Sport Science, Human Performance Lab, University of Wisconsin â?? La Cros, USA, Email:

Published: 26-Nov-2021

Introduction

The capacity of cellular oxidative phosphorylation (OXPHOS) â?? a direct measure of mitochondrial function â?? is a result of evolution, age, gender, lifestyle, and environment (EAGLE). Increasingly, western lifestyle and aging contribute to mitochondrial dysfunction and the current epidemic of preventable diseases, including neurodegenerative and cardiovascular diseases, obesity, diabetes, and various types of cancer. The mitObesity epidemic leads to multimorbidity in aging and threatens to overwhelm the capacity of healthcare systems.

Training in mitochondrial physiology and bioenergetics, therefore, has high relevance to society. The ‘Blue Book’ on Mitochondrial Pathways and Respiratory Control presents a fundamental introduction to OXPHOS analysis for students and researchers in life sciences â?? from evolutionary biology to medical and environmental applications. It combines concepts of bioenergetics and biochemical pathways related to mitochondrial core energy metabolism, provides the basis for substrate-uncoupler-inhibitor titration (SUIT) protocols, and updates the terminology consistent with the MitoEAGLE white paper on Mitochondrial Physiology.

It is now our responsibility to transfer the enthusiasm for innovation, reproducibility, and quality in science, and to translate mitochondrial research into visionary healthcare solutions.

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery.