Studies On Oxidative Phosphorylation In Mitochondrial Systems

Methods in Toxicology, Volume 2: Mitochondrial Dysfunction provides a source of methods, techniques, and experimental approaches for studying the role of abnormal mitochondrial function in cell injury. The book discusses the methods for the preparation and basic functional assessment of mitochondria from liver, kidney, muscle, and brain; the methods for assessing mitochondrial dysfunction in vivo and in intact organs; and the structural aspects of mitochondrial dysfunction are addressed. The text also describes chemical detoxification and metabolism as well as specific metabolic reactions that are especially important targets or indicators of damage. The methods for measurement of alterations in fatty acid and phospholipid metabolism and for the analysis and manipulation of oxidative injury and antioxidant systems are also considered. The book further tackles additional methods on mitochondrial energetics and transport processes; approaches for assessing impaired function of mitochondria; and genetic and developmental aspects of mitochondrial disease and toxicology. The text also looks into mitochondrial DNA synthesis, covalent binding to mitochondrial DNA, DNA repair, and mitochondrial dysfunction in the context of developing individuals and cellular differentiation. Microbiologists, toxicologists, biochemists, and molecular pharmacologists will find the book invaluable.

Mitochondrial diseases are often hard to diagnose. From the time they were first researched without animal models, patients of mitochondrial diseases were of equal interest to both clinical and basic scientists. With the new research done, this book includes updates on the normal structure, function, and molecular biology of the mitochondrial respiratory chain, information on traditional diagnostical methodologies, and an overview of the diagnostic promise of new technologies. The hypermetabolism of Luft disease, although only seen twice, is also studied. There are critical reviews of symptoms and signs associated with syndromes, as well as updates on the genetic defects of either the mitochondrial or the nuclear genome responsible for many disorders.

Mitochondria are far more than the “powerhouse” of the cell as they have classically been described. In fact, mitochondria biological activities have progressively expanded to include not only various bioenergetic processes but also important biosynthetic pathways, calcium homeostasis and thermogenesis, cell death by apoptosis, several different signal transduction pathways mainly related to redox control of gene expression and so on. This functional and structural complexity may undergo important derangements so to justify the definition of ‘mitochondrial medicine’, which should include all the clinical consequences of congenital or acquired mitochondrial dysfunctions. There are actually a growing number of studies which assign a significant pathogenic role to damaged mitochondria in different diseases: ischemia/reperfusion injury, neurodegenerative diseases, cancer with its dramatic sequelae (i.e, metastasis), metabolic syndrome, hyperlipidemias, just to mention a few of the most important pathologies. In this context, a further aspect that should not be disregarded is the interaction of pharmacological agents with mitochondria, not only in regard of the toxicological aspects but, above all, of the potential therapeutic applications. In fact, it is interesting to note that, while the properties of different so-called “mitoxicants” are well-known, the subtle linkages between drugs and mitochondria is still in need of a real pharmacological and therapeutic control at the clinical level. This lack of consideration can often lead to an underestimation of unwanted toxic effects but also of desirable therapeutic activities. A reevaluation of the potential clinical role of mitochondria could give a new light on some yet obscure aspects of human pathophysiology.

This book will describe the nuclear encoded genes and their expressed proteins of mitochondrial oxidative phosphorylation. Most of these genes occur in eukaryotic cells, but not in bacteria or archaea. The main function of mitochondria, the synthesis of ATP, is performed at subunits of proton pumps (complexes I, III, IV and V), which are encoded on mitochondrial DNA. The nuclear encoded subunits have mostly a regulatory function. However, the specific physiological functions of the nuclear encoded subunits of complexes I, III, IV, and V are mostly unknown. New data indicates that they are essential for life of higher organisms, which is characterized by an adult life without cell division (postmeiotic stage) in most tissues, after the juvenile growth. For complex IV (cytochrome c oxidase) some of these subunits occur in tissue-specific (subunits IV, VIa, VIb, VIIa, VIII), developmental-specific (subunits IV, VIa, and VIIa) as well as species-specific isoforms. Defective genes of some subunits were shown to induce mitochondrial diseases. Mitochondrial genes and human diseases will also be covered.

Neuropsychiatric disorders such as schizophrenia, mood disorders, Alzheimer’s disease, epilepsy, alcoholism, substance abuse and others are one of the most debilitating illnesses worldwide characterizing by the complexity of the causes, and lacking the laboratory tests that may promote diagnostic and prognostic procedures. Recent advances in neuroscience, genomic, genetic, proteomic and metabolomic knowledge and technologies have opened the way to searching biomarkers and endophenotypes, which may offer powerful and exciting opportunity to understand the etiology and the underlying pathophysiological mechanisms of neuropsychiatric disorders. The challenge now is to translate these advances into meaningful diagnostic and therapeutic advances. This book offers a broad synthesis of the current knowledge about diverse topics of the biomarker and endophenotype strategies in neuropsychiatry. The book is organized into four interconnected volumes: “Neuropsychological Endophenotypes and Biomarkers” (with overview of methodological issues of the biomarker and endophenotype approaches in neuropsychiatry and some technological advances), “Neuroanatomical and Neuroimaging Endophenotypes and Biomarkers”, “Metabolic and Peripheral Biomarkers” and “Molecular Genetic and Genomic Markers”. The contributors are internationally and nationally recognized researchers and experts from 16 countries. This four-volume handbook is intended for a broad spectrum of readers including neuroscientists, psychiatrists, neurologists, endocrinologists, pharmacologists, clinical psychologists, general practitioners, geriatricians, health care providers in the field of neurology and mental health interested in trends that have crystallized in the last decade, and trends that can be expected to further evolve in the coming years. It is hoped that this book will also be a useful resource for the teaching of psychiatry, neurology, psychology and mental health.