Natural vitamin E includes two groups of closely related fat-soluble compounds, tocopherols and tocotrienols, each composed of four isoforms. alpha-Tocopherol is a very well-known potent antioxidant and radical scavenger in chemical and biological systems. Its structure has served as template for design and synthesis of more potent antioxidant analogues with regard to its potential protective effect against certain diseases associated with ageing -- particularly cancer and heart disease. This book presents and discusses current research in the study of tocopherols. Topics discussed include quantification, antioxidant activity and pro-oxidant effects of alpha-tocopherols from several sources, design, synthesis and biological activity of tocopherol based hybrid molecules. Chromatographic separation of tocopherol isomers.

This book presents an overview of sphingolipids: biology, synthesis and functions. The topics analysed in this book cover a broad spectrum of functions played by sphingolipids including: the role of sphingomyelin in the regulation of membrane physical state; tricyclic antidepressants as modulators of sphingolipid turnover and cell sensitivity to insulin action; sphingolipid diversity, biosynthesis and regulation; metabolism of glycolipids at the cell's surface: modulation and functional implications; the specific role of sphingomyelins in cell physiology; the role of sphingosine-based lipids using sphingolipidomics; sphingolipids and ceramides of aqueous humor and trabecular meshwork; the effect of membrane microdomains containing sphingolipids on lipid peroxidation; and roles of sphingolipids in skeletal development and homeostasis.

Many studies have shown that free radical damage and lipid peroxidation increase as a function of the degree of unsaturation of the fatty acids present in the phospholipids of biological membranes. Membrane phospholipids are particularly susceptible to oxidation not only because of their highly polyunsaturated fatty acid content but also because of their association in the cell membrane with non-enzymatic and enzymatic systems capable of generating pro-oxidative-free radical species. There are two broad outcomes to lipid peroxidation: structural damage to membranes and generation of secondary products. Membrane damage derives from the generation of fragmented fatty acyl chains, lipidlipid cross-links, lipidprotein cross-links and endocyclisation to produce isoprostanes and neuroprostanes. These processes combine to produce changes in the biophysical properties of membranes that can have profound effects on the activity of membrane-bound proteins. The consequence of peroxidation of unsaturated fatty acids is severe: damage of membranes function, enzymatic inactivation, toxic effects on the cellular division, etc. This new book presents and discusses current research on oxidative stress, and lipid oxidation non-inhibited and inhibited; assessment of oxidative balance in the lipo- and hydro-philic cellular environment in biological systems; mass spectrometry detection of protein modification by cross-reaction with lipid peroxidation products; diagonal gel electrophoretic analysis of protein disulfides: principles and applications. Other chapters describe: heavy metals exposure and cells oxidative damage; biodegradation of metallic biomaterials: its relation with the generation of reactive oxygen species; Oxidative modifications of proteins in the aging heart; role of reactive oxygen species as signalling molecules involved in the regulation of physiological processes of the nervous system; oxidative stress in diabetes and hypertension treated with alternative therapy of medicinal plants; impairment of redox homeostasis of tissue damage in inborn errors of metabolism with intoxication: insights from human and animal studies and finally lipid peroxidation of phospholipids in the vertebrate retina or in liposomes made of retinal lipids: similarities and differences are described.

This book presents an overview of polyunsaturated fatty acids (pufas): food sources, health effects and significance in biochemistry. The topics analyzed cover a broad spectrum of polyunsaturated fatty acids and present new information in this area of research. The topics analyzed include: microalgae as a source of omega-3 polyunsaturated fatty acids; polyunsaturated fatty acids (pufas) in human health; polyunsaturated fatty acids in artificial membranes modeled by the langmuir monolayer technique; lipid peroxidation at the cross roads of cell proliferation and cancer; advancement in the knowledge of polyunsaturated fatty acids, from discovery to now; the discussion of whether or not polyunsaturated fatty acids are beneficial for failing hearts; polyunsaturated fatty acids (n3) of vegetal origin; proteomic approaches to understand the health effects of marine omega-3 pufa; essential fatty acids; and health implications and threats to sources.

This book presents an overview of the role in biological processes and health effects produced by indoleamines, which are ubiquitous and versatile molecules with important physiological functions. The topics analysed in this book cover a broad spectrum of functions played by indoleamines including the role of indoleamines in reducing free radical damage and oxidative stress; melatonin; endogenous sources and role in the regulation of fish reproduction; the neuroimmune roles of indoleamine pathways in cancer; tryptophan damage signal and indoleamine 2, 3-dioxygenase; the health effects of indoleamines on cognition, in the prevention of brain aging and age-related diseases; melatonin as an ocular anti-inflammatory; the relations between water-soluble B vitamins and indoleamines; melatonin in neurodegenerative, psychiatric and systemic inflammatory disorders; tryptophan, indolamines and sleep; from human milk to tryptophan-enriched diets; function of indoleamines in biological processes with emphasis on lipid peroxidation and indoleamines in edible plants; and the role in human health effects.