Non-vesicular intracellular cholesterol transport is an important mechanism for maintaining membrane cholesterol homeostasis. Recent reports of studies directed at soluble cholesterol transport proteins indicate that aberrant expression of the START proteins may contribute to disease states associated with disorders in cholesterol homeostasis. This is an exciting new direction in the field and the purpose of this book will be to highlight the current research directed at potential roles for the START family in diabetes, cancer and atherogenesis. This book also provides a personal and historical perspective of the discovery-to-publication journey that the authors had for their particular START domain family member. The goal will be to provide perspectives to graduate students, post-doctoral fellows and endocrinology fellows on the research discovery process.
INTRODUCTION AND RATIONALE FOR INTRACELLULAR CHOLESTEROL TRAFFICKING This volume is an elaboration of an earlier small meeting held in St. Louis, Missouri. In April 1997, many of the authors met for a two-day meeting devoted entirely to intracellular cholesterol trafficking. The rationale for this meeting was that investigators interested in this topic worked in a variety of fields, and rarely, if ever, all met together. Everybody knew each other's papers but mostly worked in isolation from one another. Understanding of cholesterol trafficking also appeared to have reached the point where it would start to rapidly expand beyond these few laboratories. Understanding of cholesterol trafficking was moving from a largely descriptive science into the molecular age. It seemed a good time to get together and see how much we agreed upon up to this point. More authors contributed to this volume than attended the St. Louis meeting. That meeting was generously funded by grants from Bristol-Myers Squibb, Merck and Company and Parke-Davis, however, the total funding available limited the size of the meeting. For the book, we are not so limited and have tried to be as inclusive as possible and pretty much invited everyone who is presently active in this area. We were quite fortunate to successfully recruit the authors we sought for each of these chapters. The authors and their contributions can be organized by particular interests and particular areas of expertise.
By stimulating adrenal gland and corticosteroid synthesis, the adrenocorticotropic hormone (ACTH) plays a central role in response to stress. In this Research Topic, a particular attention has been given to the recent developments on adrenocortical zonation; the growth-promoting activities of ACTH; the various steps involved in acute and chronic regulation of steroid secretion by ACTH, including the effect of ACTH on circadian rhythms of glucocorticoid secretion. The Research Topic also reviews progress and challenges surrounding the properties of ACTH binding to the MC2 receptor (MC2R), including the importance of melanocortin-2 receptor accessory protein (MRAP) in MC2R expression and function, the various intracellular signaling cascades, which involve not only protein kinase A, the key mediator of ACTH action, but also phosphatases, phosphodiesterases, ion channels and the cytoskeleton. The importance of the proteins involved in the cell detoxification is also considered, in particular the effect that ACTH has on protection against reactive oxygen species generated during steroidogenesis. The impact of the cellular microenvironment, including local production of ACTH is discussed, both as an important factor in the maintenance of homeostasis, but also in pathological situations, such as severe inflammation. Finally, the Research Topic reviews the role that the pituitary-adrenal axis may have in the development of metabolic disorders. In addition to mutations or alterations of expression of genes encoding components of the steroidogenesis and signaling pathways, chronic stress and sleep disturbance are both associated with hyperactivity of the adrenal gland. A resulting effect is increased glucocorticoid secretion inducing food intake and weight gain, which, in turn, leads to insulin and leptin resistance. These aspects are described in detail in this Research Topic by key investigators in the field. Many of the aspects addressed in this Research Topic still represent a stimulus for future studies, their outcome aimed at providing evidence of the central position occupied by the adrenal cortex in many metabolic functions when its homeostasis is disrupted. An in-depth investigation of the mechanisms underlying these pathways will be invaluable in developing new therapeutic tools and strategies.
Knowledge of cholesterol and its interaction with protein molecules is of fundamental importance in both animal and human biology. This book contains 22 chapters, dealing in depth with structural and functional aspects of the currently known and extremely diverse unrelated families of cholesterol-binding and cholesterol transport proteins. By drawing together this range of topics the Editor has attempted to correlate this broad field of study for the first time. Technical aspects are given considerable emphasis, particularly in relation cholesterol reporter molecules and to the isolation and study of membrane cholesterol- and sphingomyelin-rich "raft" domains. Cell biological, biochemical and clinical topics are included in this book, which serve to emphasize the acknowledged and important benefits to be gained from the study of cholesterol and cholesterol-binding proteins within the biomedical sciences and the involvement of cholesterol in several clinical disorders. It is hoped that by presenting this topic in this integrated manner that an appreciation of the fact that there is much more that needs to be taken into account, studied and understood than the widely discussed "bad and good cholesterol" associated, respectively, with the low- and high-density lipoproteins, LDL and HDL.
In this Handbook of Experimental Pharmacology on “High Density Lipoproteins – from biological understanding to clinical exploitation” contributing authors (members of COST Action BM0904/HDLnet) summarize in more than 20 chapters our current knowledge on the structure, function, metabolism and regulation of HDL in health and several diseases as well as the status of past and ongoing attempts of therapeutic exploitation. The book is of interest to researchers in academia and industry focusing on lipoprotein metabolism, cardiovascular diseases and immunology as well as clinical pharmacologists, cardiologists, diabetologists, nephrologists and other clinicians interested in metabolic or inflammatory diseases.
Offering multidisciplinary guidance to all health care practitioners who provide clinical care for children and adolescents, the 7th Edition of Emans, Laufer, Goldstein’s Pediatric & Adolescent Gynecology has been extensively revised to keep you up to date in this complex field. You’ll find comprehensive coverage of the full spectrum of medical and surgical approaches to common and uncommon problems – everything from infants with vulvar rashes, to the child with early or late onset of puberty, to adolescents and young adults with ovarian cysts or STDs. More than 40 experts in the field, led by editors from Boston Children’s Hospital and Harvard Medical School, have contributed to ensure this classic text remains relevant and useful in daily practice.
Cholesterol is an essential component of the plasma membrane. Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), although a minor phospholipid, is the most abundant membrane phosphoinositide. Both lipids play key roles in a variety of cellular functions including as signalling molecules and major regulators of protein function. Studies on these important lipids have traditionally focused on the effect of each lipid individually. Accumulating evidence indicates, however, that these lipids may cross-regulate each other’s levels. Furthermore, it is becoming evident that cholesterol and PI(4,5)P2 can act together to modulate protein function and biological processes. This book provides an overview of cellular functions and molecular mechanisms in which cholesterol and PI(4,5)P2 functions extend from parallel existence to crosstalk. It includes four sections. The first section introduces the reader to cholesterol and PI(4,5)P2. The second section demonstrates the mutual influence of these two critical lipids on their levels. The third section, divided into two parts, describes the co-modulation of protein function by cholesterol and PI(4,5)P2. The first part focuses on ion channels and the second - on lipid transfer proteins. The fourth section highlights other cellular processes at the intersection of cholesterol and PI(4,5)P2 involvement. Collectively, the book portrays the emerging relationship between cholesterol and PI(4,5)P2 in a broad array of biological systems and processes. The book will be of interest to a wide audience of research scientists with an interest in the biophysical properties of lipids and the physiological consequences of their presence in biological systems, as well as graduate students, postdoctoral trainees, basic and clinical researchers, and pharmaceutical scientists. Specifically, the content will be relevant to researchers in the fields of biochemistry, molecular biophysics, pharmacology, neurobiology, cardiovascular biology, among others. Provides a comprehensive overview of the current knowledge of the interplay between cholesterol and PI(4,5) P2 Provides an overview of the emerging relationship between cholesterol and PI(4,5)P2 in biological systems and processes Discusses cellular processes and molecular mechanisms where lipid functions extend from parallel existence to crosstalk
This book provides the first comprehensive coverage of the quickly evolving research field of membrane contact sites (MCS). A total of 16 chapters explain their organization and role and unveil the significance of MCS for various diseases. MCS, the intracellular structures where organellar membranes come in close contact with one another, mediate the exchange of proteins, lipids, and ions. Via these functions, MCS are critical for the survival and the growth of the cell. Owing to that central role in the functioning of cells, MCS dysfunctions lead to important defects of human physiology, influence viral and bacterial infection, and cause disease such as inflammation, type II diabetes, neurodegenerative disorders, and cancer. To approach such a multifaceted topic, this volume assembles a series of chapters dealing with the full array of research about MCS and their respective roles for diseases. Most chapters also introduce the history and the state of the art of MCS research, which will initiate discussion points for the respective types of MCS for years to come. This work will appeal to all cell biologists as well as researchers on diseases that are impacted by MCS dysfunction. Additionally, it will stimulate graduate students and postdocs who will energize, drive, and develop the research field in the near future.
