The Mythical Mitochondrial Function in Lung Health and Disease

Arturo Solís Herrera

doi:10.31031/ggs.2020.06.000638

Abstract

Mitochondria is described as various key functions such as cell cycle regulation, proliferation, apoptosis, and innate immune responses, in addition to power generation. The mitochondrion is relatively simple as consists of the outer membrane, inner membrane, proteins, lipids, and mitochondrial DNA that has substantial similarity to bacterial DNA. Mitochondrial morphology is in a dynamic state being modified continuously enabling the organelle to move, fuse, and fission depending on functional requirements of the cell, Although the changing states of mitochondria are described in detail, researchers are usually silent about the energy needed to maintain such dynamics. Mitochondria disorders are quite common in many diseases, such as neurodegenerative diseases. Compared to other organs such as heart, brain and liver, the lung has fewer mitochondria. Theoretically lungs rely on glycolysis more than oxidative phosphorylation for energy production. Furthermore, the role of mitochondria in normal lung homeostasis and importance of mitochondrial dysfunction/damage in the pathology of lung diseases remain poorly understood.

Highlights

The role of mitochondria in normal lung homeostasis and its importance in the pathology of lung diseases remain poorly understood
Mitochondrial morphology is in a dynamic state being modified continuously enabling the organelle to move, fuse, and fission depending on functional requirements of the cell, the changing states of mitochondria are described in detail, researchers are usually silent about the energy needed to maintain such dynamics
We must bear in mind that mitochondria are not an energy-independent organelle, which means that it requires energy to carry out its delicate and exact functions, as well as to preserve form

Summary

Background

Mitochondria are key cellular organelles that supply cellular ATP and integrate redox signaling, apoptotic balance, and biosynthetic pathways in the cell. Mitochondria regulate various metabolic functions and generate >95 % of the required metabolic energy that is driven by both nuclear and mitochondrial genomes; the mystery remains about where the energy that mitochondria needs to carry out its delicate functions where it comes from comes from?. Mitochondrial ROS production is tightly regulated and is generated by one electron reduction of molecular O 2 to yield superoxide (O2-.) that is subsequently converted to hydrogen peroxide (H2O2) by mitochondrial manganese-dependent superoxide dismutase (SOD2). The regulation of functions requires energy, the addition of an electron to molecular oxygen requires energy, the subsequent conversion to hydrogen peroxide requires energy, and the action of superoxide dismutase requires energy, and the literature is silent about it

Introduction

Conclusion