Membrane Transporters And Channels As Targets For Drugs

Transporters and channels are membrane proteins that mediate the traffic of metabolites, water and ions across biological membranes. Membrane transport proteins are crucial to maintain homeostasis and assure cell survival upon intracellular or environmental stress. A failure of any of these transport systems may have dramatic consequences for cell function. There is increasing evidence that membrane transport proteins play important functions in healthy conditions and that their absence or dysfunction may cause diseases. In recent years much attention has been paid to diseases resulting from defective transporters (“carrier diseases”) and ion channels (“channelopathies”). Very interestingly, altered expression of transporters has been described in several human pathologies. On this basis, many transport proteins are well acknowledged targets for drugs. Many others are involved in drug delivery and disposition and/or are considered potential targets. Others are off-targets for drugs and then, are responsible for side effects. Thus, membrane protein drug discovery is now an emerging field where the search for physiological mechanisms of regulation and for chemical compounds as modulators of transport activity, present new opportunities for drug development and for new therapies. This Research Topic addresses the latest research advances in membrane transport proteins, stimulating future research on these important protein families.

Because progress in the field of transporters has been extraordinary, this volume will focus on recent advances in our understanding of the structure, function, physiology, and molecular biology of membrane transporters. There will be an emphasis on transporters as molecular targets for drug delivery and disposition in the body.

Studies of membrane transporters have had great impact on our und- standing human diseases and the design of effective drugs. About 30% of current clinically marketed drugs are targeting membrane transporters or channels. Membrane Transporters: Methods and Protocols provides various practical methodologies for the ongoing research on membrane transporters. To provide readers the most up-to-date information, several emerging fields and methodologies are embraced in this book, including pharmacogenomics, bioin-formatics, and microarray technology. Pharmacogenomics studies of membrane transporters are useful in drug discovery and in predicting drug responses in the clinic. In this volume, the current status of pharma- genomics studies of transporters is reviewed and research methodologies in this field are described. Transporter classification is important in studying the structure and function of membrane transporters and has thus triggered intensive interest in recent years. Membrane Transporters: Methods and Protocols provides a systematic classification of all transmembrane transport proteins found in living org- isms on Earth. This classification system will be helpful for further studies on various aspects of membrane transporters, especially for such large-scale gene expression studies as those employing microarray technologies. Bioinformatics is frequently used in transporter studies and has become indispensable for all kinds of research methods. Commonly used bio- formatics methods, such as databases and tools for sequence analysis and - tif studies, are explained in order to facilitate membrane transporters research. Because of heterogeneous sources and tremendous amounts of data, data in- gration has become one of the most important issues in transporter studies.

As opposed to other books on the topic, this volume is unique in also covering emerging transporter targets. Following a general introduction to the importance of targeting transporter proteins with drugs, the book systematically presents individual transporter classes and explains their pharmacology and physiology. The text covers all transporter families with known or suspected importance as drug targets, including neurotransmitter transporters, ABC transporters, glucose transporters and organic ion transporters. The final part discusses recent advances in structural studies of transport proteins, assay methods for transport activity, and the systems biology of transporters and their regulation. With its focus on drug development issues, this authoritative overview is required reading for researchers in industry and academia targeting transport proteins for the treatment of disease.

With contributions by numerous experts

This text provides practical methodologies of the ongoing research on membrane transporters, considering applications of transporter technologies in drug discovery and development.

Understanding and quantifying the effects of membrane transporters within the human body is essential for modulating drug safety and drug efficacy. In this first volume on Drug Transporters, the current knowledge and techniques in the transporter sciences and their relations to drug metabolism and pharmacokinetics are comprehensively reviewed. The second volume of the book is specifically dedicated to emerging science and technologies, highlighting potential areas for future advances within the drug transporter field. The topics covered in both volumes ensure that all relevant aspects of transporters are described across the drug development process, from in silico models and preclinical tools through to the potential impact of transporters in the clinic. Contributions are included from expert leaders in the field, at-the-bench industrial scientists, renowned academics and international regulators. Case studies and emerging developments are highlighted, together with the merits and limitations of the available methods and tools, and extensive references to reviews on specific in-depth topics are also included for those wishing to pursue their knowledge further. As such, this text serves as an essential handbook of information for postgraduate students, academics, industrial scientists and regulators who wish to understand the role of transporters in absorption, distribution, metabolism, and excretion processes. In addition, it is also a useful reference tool on the models and calculations necessary to predict their effect on human pharmacokinetics and pharmacodynamics.