The myopathic features of the mitochondrial cytopathies

Abstract

This chapter describes the electron transport and life span in Caenorhabditis elegans. The electron transport chain or oxidative phosphorylation (OXPHOS) system is located within the mitochondrial inner membrane and is intimately responsible for three important processes: production of adenosine triphospahte (ATP), generation of reactive oxygen species (ROS), and regulation of programmed cell death, or apoptosis. Mitochondrial deficiencies, which disturb energy metabolism and reduce ATP production, cause a variety of diseases, including human congenital neurodegenerative diseases like mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes(MELAS), myoclonic epilepsy with ragged red fibers (MERRF), Kearns-Sayre syndrome (KSS), chronic progressive external ophthalmoplegia (CPEO), neuropathy, ataxia, and retinitis pigmentosa (NARP), maternally inherited Leigh syndrome (MILS), and Leber hereditary optic neuropathy (LHON). Many of the ultimate manifestations of these diseases are triggered by a metabolic imbalance known as lactic acidosis, which is characterized by a high lactate/pyruvate ratio and is a characteristic feature of a variety of other metabolic disorders in addition to mitochondrial diseases. The reduction of energy metabolism reduces ROS generation from mitochondria and consequently extends life span. There are a few reports of mitochondria DNA (mtDNA) research in C. elegans.