This reference work focuses on the enzyme systems that participate in the metabolism of chemicals and other xenobiotics, with emphasis being placed on drug metabolism. Each chapter focuses on a specific enzyme system.

This book provides a comprehensive, organized, and concise overview of xenobiotic metabolic enzymes and their health implications. The subjects addressed are broad in scope with an emphasis on recent advances in research on biochemical and biomedical aspects of these enzymes. The xenobiotics discussed include not just drugs, but also food, smoke, and other environmental chemicals. The subjects covered in this work include: metabolic enzymes and their catalyzed reactions, reactive intermediates generated from metabolic activation, oxidative stress mediated by electrophilic reactive intermediates, bioactivation - mediated cellular and functional damages, activation of Nrf2 – ARE pathway, genetic variations affecting metabolic enzyme expression, enzyme polymorphisms affecting xenobiotic - mediated toxicity, induction of metabolic enzymes for health benefits, and a diversity of metabolic enzyme modulators.

Cytochrome P450: Structure, Mechanism, and Biochemistry, third edition is a revision of a review that summarizes the current state of research in the field of drug metabolism. The emphasis is on structure, mechanism, biochemistry, and regulation. Coverage is interdisciplinary, ranging from bioinorganic chemistry of cytochrome P450 to its relevance in human medicine. Each chapter provides an in-depth review of a given topic, but concentrates on advances of the last 10 years.

The EPA commissioned The National Academies to provide advice on the vexing question of whether and, if so, under what circumstances EPA should accept and consider intentional human dosing studies conducted by companies or other sources outside the agency (so-called third parties) to gather evidence relating to the risks of a chemical or the conditions under which exposure to it could be judged safe. This report recommends that such studies be conducted and used for regulatory purposes only if all of several strict conditions are met, including the following: The study is necessary and scientifically valid, meaning that it addresses an important regulatory question that can't be answered with animal studies or nondosing human studies; The societal benefits of the study outweigh any anticipated risks to participants. At no time, even when benefits beyond improved regulation exist, can a human dosing study be justified that is anticipated to cause lasting harm to study participants; and All recognized ethical standards and procedures for protecting the interests of study participants are observed. In addition, EPA should establish a Human Studies Review Board (HSRB) to evaluate all human dosing studiesâ€"both at the beginning and upon completion of the experimentsâ€"if they are carried out with the intent of affecting the agency's policy-making.

Drug Metabolism: Current Concepts provides a comprehensive understanding of the processes that take place following ingestion of a medicinal agent or xenobiotic, with an emphasis on the crucial role of metabolism (biotransformation). How a sound knowledge of these phenomena is incorporated into the design of effective new drug candidates is also explained. The user-friendly text focuses on concepts rather than extraneous details and is supported by many illustrated examples of biotransformations as well as frequent references to current critical reviews and articles highlighting the nature of research objectives in this vibrant area of medicinal development. The final topic on strategies for drug design relies on the background provided by the rest of the book. This book is ideally suited as an advanced text for courses in drug metabolism for students of medicine, pharmacy, pharmacology, biochemistry; and for courses in drug design and drug delivery for students of medicinal chemistry. It is also appropriate for professional seminars or courses that relate to the fate of a drug in the body, drug interactions, adverse reactions and drug design.

Humans are exposed to foreign compounds such as drugs, household products and environmental chemicals by swallowing or breathing. Also, food is considered a foreign compound. Such foreign compounds can be non-essential and non-functional to life, and commonly are referred to as xenobiotics. Some xenobiotics are not toxic; however, many of them are potentially toxic or become toxic after conversion to metabolic intermediates. A considerable number of foreign compounds belong to non-polar, lipophilic substances. Lipophilic compounds are not soluble in water. Metabolic conversion of lipophilic foreign compounds to facilitate their removal from the body is essentially carried out by biochemical reactions catalyzed by two classes of metabolizing enzymes, namely, activation enzymes and detoxification enzymes. Activation enzyme-catalyzed functionalization reaction introduces a functional group to a lipophilic compound. Functionalization modifies many foreign compounds to form reactive intermediates capable of interacting with cellular components (proteins, DNA and lipids), leading to a variety of conditions for diseases. Functionalized compounds are further metabolized through detoxification enzyme-catalyzed reactions, which result in an increase in the solubility of parent compounds and an inactivation of metabolic intermediates, thus facilitating their excretion from the body. To minimize the exposure of potentially toxic metabolic intermediates, it is essential to keep them at a minimum level. Extensive investigations have revealed that foreign compound-metabolizing enzymes exhibit genetic polymorphisms. Variations in their activities can produce different results as to the susceptibility to potential toxic effects. Moreover, the expressions of activation enzymes and detoxification enzymes are inducible. A number of chemical compounds are capable of acting as modulators for these two classes of enzymes. These findings have lead to the proposal of modulating metabolizing enzymes as a useful approach for human health benefits. Importantly, many of these chemical compounds are present in human daily diets. There are many advances that have been made in the past decades towards the understanding of functions and implications of activation enzymes and detoxification enzymes. An organized, concise overview is needed for the readers who are initially exposed to this important subject, particularly for students and researchers in the areas of biomedical sciences, biochemistry, nutrition, pharmacology and chemistry. This book is intended to serve this purpose as an introduction to the subject. Furthermore, major topics in the book, excluding catalytic reactions and structural properties, may have interest to other readers who have knowledge of basic sciences and understanding enzyme related information. The book discusses subjects associated with foreign compound metabolizing enzymes with emphasis on biochemical aspects, including lipophilic foreign compounds, catalytic properties, reactive intermediates, biomedical and biochemical effects, genetic polymorphisms, enzyme inducibility, enzyme modulation for health benefits, dietary related enzyme modulators, and structural characteristics of enzyme inducers.

Completely revised and updated, Developmental and Reproductive Toxicology: A Practical Approach, Second Edition draws together valuable information typically scattered throughout the literature, plus some not previously published, into one complete resource. In addition to the traditional aspects of developmental toxicity testing, the book covers e