One of the major breakthroughs of the last decade in the understanding of energy homeostasis is the identification of a reciprocal control between circadian rhythmicity and cellular metabolism. Circadian rhythmicity is a fundamental endogenous process of almost every organism living on Earth. For instance, the alternation of hunger and satiety is not continuous over 24 h, but is instead structured in time along the light/dark cycle. In mammals, the temporal organization of metabolism, physiology and behavior around 24 h is controlled by a network of multiple cellular clocks, synchronized via neuronal and hormonal signals by a master clock located in the suprachiasmatic nuclei of the hypothalamus. This central circadian conductor in the brain is mainly reset by ambient light perceived by the retina, while secondary circadian clocks in other brain areas and peripheral organs can be reset by meal timing. Chronic disruption of circadian rhythms, as seen in human shift-workers (up to 20% of the active population), has been associated with the development of a number of adverse mental and metabolic conditions. Understanding of the functional links between circadian desynchronization and overall health in animal models and humans, however, is still scarce. Interactions between circadian clocks and metabolism can occur at different levels: the molecular clockwork, internal synchronization via neuro-hormonal signals, or external synchronization via photic or feeding cues. This Research Topic comprises a number of reviews as well as research and methods articles that feature recent advancements in the mechanisms linking circadian clocks with energy metabolism, and the pathophysiological implications of these interactions for metabolic health.

This title includes a number of Open Access chapters.Providing a nuanced study of the connections between sleep, circadian rhythms, and metabolis, this informative book examines how circadian actions affect the liver and adipose tissue, the brain, and metabolism. This important book introduces the reader to circadian rhythms in the body and the ext

Recent years have seen spectacular advances in the field of circadian biology. These have attracted the interest of researchers in many fields, including endocrinology, neurosciences, cancer, and behavior. By integrating a circadian view within the fields of endocrinology and metabolism, researchers will be able to reveal many, yet-unsuspected aspects of how organisms cope with changes in the environment and subsequent control of homeostasis. This field is opening new avenues in our understanding of metabolism and endocrinology. A panel of the most distinguished investigators in the field gathered together to discuss the present state and the future of the field. The editors trust that this volume will be of use to those colleagues who will be picking up the challenge to unravel how the circadian clock can be targeted for the future development of specific pharmacological strategies toward a number of pathologies.

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 summarizes the recent advances for the understanding of circadian clock system in the regulation of drug metabolism and pharmacokinetics. Basic knowledge in the field of circadian clock and pharmacokinetics are systemically introduced to make it easier for readers to understand the entire book's contents. The rhythmic expression of DMEs (drug-metabolizing enzymes) and transporters are summarized, and the underlying mechanisms thereof (i.e., regulation by circadian oscillators) are discussed. Typically, evidence for the DME- and transporter-mediated chronopharmacokinetics, chronotoxicity and chronoefficacy are highlighted in this book.

This excellent book describes the roles of the suprachiasmatic nucleus (SCN) of the hypothalamus as a regulatory center of homeostatic mechanism and a circadian oscillator in mammals, including humans. The authors emphasize two important points based on their findings: 1) SCN plays a critical role in central regulation of energy metabolism through which a constant supply of glucose to the central nervous system (CNS) is well maintained; and 2) neurons responsible for the regulation of energy metabolism are located in the ventrolateral part of the SCN and receive retinal neural inputs through both the retinohypothalamic tract and the geniculohypothalamic tract. The authors then discuss the evolutionary importance of these points to the survival of mammals on earth. Other topics examined include the involvement of light in the regulation of neural activity of the autonomic nervous system through the retina and SCN, in addition to the relation of the SCN with regulations of other autonomic nerve functions, such as blood pressure and body temperature. Central Regulation of Energy Metabolism with Special Reference to Circadian Rhythm is important reading for researchers and students in neuroendocrinologists, neurobiologists, biochemists, endocrinologists, physiologists, chronobiologists, psychologists, pharmacologists, and others interested in the topic.

When we eat may be as important as what we eat. Like most people, you probably wake up, get hungry for meals and doze off in bed around the same time every day. If you’ve ever experienced jet lag or pulled an all-nighter, you know that this schedule can easily be thrown off kilter. But for some people, that imbalance—difficulty sleeping at night, hunger at odd times, or sudden fatigue at noon—is a constant. If you're one of those people, Dr. Satchin Panda, one of the leading researchers on circadian rhythms, has a plan to reset your body clock. Beginning with an in-depth explanation of the circadian clock—why it’s important, how it works, and how to know it isn’t working—The Circadian Code outlines lifestyle changes to make to get back on track. It's a concrete plan to enhance weight loss, improve sleep, optimize exercise, and manage technology so that it doesn’t interfere with your body’s natural rhythm. Dr. Panda’s life-changing methods show you how to prevent and reverse ailments like diabetes, cancer, and dementia, as well as microbiome conditions like acid reflux, heartburn, and irritable bowel disease.