Mechanisms Of Circadian Systems In Animals And Their Clinical Relevance

Well known experts in the field of Chronobiology from around the world, provide an integrative view of the state of the art of circadian biology. At present, genetic and epigenetic interaction of regulatory pathways among circadian oscillators, metabolic networks, cellular differentiation and neuronal communication are subject of intense scrutiny. The book is organized in three sections: The first includes selected examples of the circadian systems of crustaceans, insects, fish, birds and mammals. The second is a detailed view of the physiological mechanisms underlying the circadian clocks in mammals. Finally, in the third section some examples of the relevance of circadian biology and circadian misalignment to health and disease are provided including nutrition and metabolism, obesity, cancer, cardiovascular and pulmonary diseases, Huntington and affective diseases. This section concludes with a brief review on gene therapy and its potential use as a therapeutic tool to correct “clock genes” pathologies. This book is aimed at all those interested in contemporary aspects of physiology, biochemistry and molecular biology applied to the study and characterization of timing systems.. It could be used as an initial approach to this field, but it also provides updated information for those already familiar with the fascinating field of Chronobiology.

Prestigious contributors describe the genetic, molecular, anatomical and neurochemical mechanisms and pathways that operate to regulate and control circadian rhythmicity and functioning in organisms ranging from unicellular algae to human beings. Also considers the implications of the basic and clinical research for humans.

Hormones, Brain and Behavior, Third Edition offers a state-of-the-art overview of hormonally-mediated behaviors, including an extensive discussion of the effects of hormones on insects, fish, amphibians, birds, rodents, and humans. Entries have been carefully designed to provide a valuable source of information for students and researchers in neuroendocrinology and those working in related areas, such as biology, psychology, psychiatry, and neurology. This third edition has been substantially restructured to include both foundational information and recent developments in the field. Continuing the emphasis on interdisciplinary research and practical applications, the book includes articles aligned in five main subject sections, with new chapters included on genetic and genomic techniques and clinical investigations. This reference provides unique treatment of all major vertebrate and invertebrate model systems with excellent opportunities for relating behavior to molecular genetics. The topics cover an unusual breadth (from molecules to ecophysiology), ranging from basic science to clinical research, making this reference of interest to a broad range of scientists in a variety of fields. Comprehensive and updated coverage of a rapidly growing field of research Unique treatment of all major vertebrate and invertebrate model systems with excellent opportunities for relating behavior to molecular genetics Covers an unusual breadth of topics and subject fields, ranging from molecules to ecophysiology, and from basic science to clinical research Ideal resource for interdisciplinary learning and understanding in the fields of hormones and behavior

With the invitation to edit this volume, I wanted to take the opportunity to assemble reviews on different aspects of circadian clocks and rhythms. Although most c- tributions in this volume focus on mammalian circadian clocks, the historical int- duction and comparative clocks section illustrate the importance of various other organisms in deciphering the mechanisms and principles of circadian biology. Circadian rhythms have been studied for centuries, but only recently, a mole- lar understanding of this process has emerged. This has taken research on circadian clocks from mystic phenomenology to a mechanistic level; chains of molecular events can describe phenomena with remarkable accuracy. Nevertheless, current models of the functioning of circadian clocks are still rudimentary. This is not due to the faultiness of discovered mechanisms, but due to the lack of undiscovered processes involved in contributing to circadian rhythmicity. We know for example, that the general circadian mechanism is not regulated equally in all tissues of m- mals. Hence, a lot still needs to be discovered to get a full understanding of cir- dian rhythms at the systems level. In this respect, technology has advanced at high speed in the last years and provided us with data illustrating the sheer complexity of regulation of physiological processes in organisms. To handle this information, computer aided integration of the results is of utmost importance in order to d- cover novel concepts that ultimately need to be tested experimentally.

This book is a fruit of a collaborative work from several international scientists. It will be a useful resource for researchers, students, and clinicians. Each individual chapter could serve as a prescribed reading for postgraduate students and clinicians specializing in and practicing clinical pharmacology and toxicology, pharmacotherapy and pharmacotherapeutics, pharmacovigilance, and toxicovigilance, as well as those involved in clinical research, drug discovery, and development. Every chapter in this book discusses and provides illustrations on the theme discussed based on authors' understanding and experience while summarizing existing knowledge. In doing so, each chapter provides a new insight that would benefit a novice as well as a seasoned reader in understanding the pharmacokinetic mechanisms and risk factors involved in the occurrence of adverse effects of drugs.

The current eBook collection includes substantial scientific work in describing how insect species are responding to abiotic factors and recent climatic trends on the basis of insect physiology and population dynamics. The contributions can be broadly split into four chapters: the first chapter focuses on the function of environmental and mostly temperature driven models, to identify the seasonal emergence and population dynamics of insects, including some important pests. The second chapter provides additional examples on how such models can be used to simulate the effect of climate change on insect phenology and population dynamics. The third chapter focuses on describing the effects of nutrition, gene expression and phototaxis in relation to insect demography, growth and development, whilst the fourth chapter provides a short description on the functioning of circadian systems as well as on the evolutionary dynamics of circadian clocks.

Chronobiology is the study of adaptations evolved at all levels of organization by living organisms to cope with regular geophysical cycles in the environment. The Earth s rotation originates alternation of light and darkness with a 24-h period; this signal allowed primordial organisms to keep track of time, adjust their internal temporal order, and anticipate external time. This capability fostered the development in living matter of endogenous temporal organization of cellular process over an approximately 24-h period. The cellular machinery that generates this ability is known as the biological clock, and its outputs as circadian rhythms. Such clocks can be found in nearly all organisms, from simple bacteria to insects, mammals, and of course, humans. The selective advantage conferred to all organisms by the biological clock comprises coordination of molecular, physiological, and behavioral processes, so as to ensure its occurrence during the daily cycle s optimal time. When organisms are maintained in an environment with strong time signals (zeitgebers) such as the light-dark cycle, each of their circadian rhythms establishes a stable relationship with each other and with the external cycle, and becomes an entrained system. Different species and different individuals within each species are coupled with their own typical phases to the natural 24-h cycle. Thus, time is embedded in our genes, and circadian clocks have emerged several times during evolution as a result of convergence to meet a common need. And although key proteins are not conserved, all clocks known to date in eukaryotes involve transcriptional-translational feedback loops. Over the last decades, chronobiology has expanded enormously, is emerging independently in many fields, and it is one of the most interdisciplinary fields in biology. While it has not been easy to understand how a biological clock works in an organism, research with different models from single-cell organisms to complex multicellular plants and animals have provided us insight concerning the ticking of the clock. Identification of circadian rhythms in biochemical and behavioral parameters in different unicellular organisms, localization of different oscillators in combination with behavioral outputs markers by neurobiological techniques in insects and mammals, as well as molecular genetics that has led to identification and cloning of clock genes in several species including humans have rendered chronobiology a diverse and dynamic discipline, with not only biological relevance but also important social and medical implications. Our goal in editing this book was to provide a comparative view of our current knowledge regarding circadian rhythms and clocks at different phylogenetic levels. The authors contributing to this volume review both circadian molecules and mechanisms in representative groups ranging from simple organisms as unicells to complex ones such as invertebrates and non-mammal and mammal vertebrates. The book reflects and is a token of different approaches to the field, such as regulation molecules and their biochemical pathways involved in either circadian or exogenous aspects of the rhythmic process and its regulation in photoautotrophic unicells and the neurobiological and molecular bases of circadian oscillators in some invertebrates and vertebrates. A number of works are focused in the importance of environmental, social, and nutrient temporal signals as synchronizing agents in insects and in different vertebrate models. These reviews are not only centered on the adult organism at the integrative level, but also provide an ontogenetic view at behavioral, physiological, and molecular levels. Furthermore, they supply evidence on several organs as potential sources of circadian signaling for different vertebrate groups, which indicates multioscillatory circadian systems similar to those proposed for some invertebrates. In Chapter 1, Rüdiger Hardeland revises the importance of tryptophan metabolic pathways in two unicells, Euglena gracilis, and the dinoflagellate, Lingulodinium polyedrum. Barbara-Ann Battelle, in Chapter 2, reviews and describes current knowledge of the circadian system of a Chelicerata, Limulus polyphemus, visual inputs into the central clock, and efferent pathways of the clock to the eyes, in addition to the molecular mechanisms underlying these processes. In Chapter 3, María Elena Durán-Lizárraga et al. review the role of different crustacean neuropeptides in the regulation of several physiological processes, such as those proposed as controlled by the circadian system of decapoda, particularly in crayfish. Claudio R. Lazzari and Teresita C. Insausti examine, in Chapter 4, the importance of circadian rhythms from insect s populations, closely associated with the history of chronobiology and the Pittendrigh pioneering work. Continuing on insects, the concept of the superorganism and the interaction of rhythms at different frequencies in different cohorts of individuals forming a colony is presented in Chapter 5 by Mirian David-Marques and Cintia Etsuko-Yamashita. In dealing with vertebrates, Raquel Carvalho and Luiz Menna-Barreto in Chapter 6 address fish from the phenomenology of circadian rhythms to the description of the underlying multioscillatory system, finally reviewing its ecological and evolutionary relevance of these species as a model. The following chapter (7) by Carolina Escobar et al. offers an integrative view of the so-called food-entrained oscillator in rodents. Then, in Chapter 8 Ivette Caldelas and colleagues provide us with an ontogenetic approach to non-visual entrainment of the circadian system, an alternative view of the food-entrained oscillator, using as a natural model the newborn rabbit. Still in the area of restricted food availability as an entraining signal, in Chapter 9 Adrián Báez-Ruíz et al. provide yet another perspective of this phenomenon, which stresses the role of liver physiology and biochemistry in the regulation of food ingestion and hepatic circadian rhythmicity. Finally, in Chapter 10 Raúl Aguilar-Roblero and colleagues review the role of the rodent suprachiasmatic nuclei as a biological clock for the mammalian circadian system, with emphasis on molecular and cellular aspects involved in the first steps of coding biological time into a signal readable by its neuronal targets. We have attempted to provide a panoramic perspective of the multiple approaches for addressing the study of the circadian system in different organisms. Selection of contributions included certain aspects of circadian rhythms not easily found in other reviews. We are indebted to the enthusiastic response of the entire group of contributors, all distinguished professors from universities from different countries, in achieving publication of this volume. We hope readers will find the text useful and that it will perhaps further promote their interest in this area of biology.

Inspired by Carlos Beyer’s 50 years of pioneering research and influence on his students and colleagues, Behavioral Neuroendocrinology builds upon Beyer’s fundamental discoveries and concepts as well as their widespread implications. It presents original research and reviews on mechanisms — genomic and non-genomic — of steroid and protein hormone action; the role of steroid metabolism, especially aromatization, protein phosphorylation, and neurotransmitter action in mediating reproductive behavior and sexual differentiation; and brain and spinal cord mechanisms in sexual behavior and analgesia. This book presents a rich diversity of topics — lactation, maternal behavior, pheromone action, chronobiology, allodynia, angiogenesis, prostate physiology, sexual motivation, and specific brain systems, including vomeronasal system, cerebellum, preoptic area, hypothalamus, and spinal cord. This book brings together, in one source, an international "family" of researchers whose work has evolved in diverse but related ways from a seminal set of discoveries and concepts in behavioral neuroendocrinology.