The enteric nervous system (ENS), also known as second brain, innervates our gastrointestinal tract controlling its functions, such as motility, fluid secretion, nutrient absorption, and even involvement in the control of immunity and inflammatory processes. In the gut, the gliocytes are known as enteric glial cells (EGCs). Enteric glial cells form a network that permeates the entire gut. Enteric glia express the cell surface hemichannel of connexin-43 (Cx43) necessary for the propagation of Ca2 + responses, necessary to maintain their functions. In this chapter, besides the development of ENS and its glial cells and the similarities with the astrocytes in the central nervous system, we approached the important role of the glial network in the control of gut homeostasis, in the interaction with the immune system, and its participation in pathological conditions. EGCs are even capable of replacing lost neurons. Thus the enteric glia is a multifunctional cell, which through its multiple interactions maintains the integrity of the ENS allowing it to be resistant to the different and constant aggressions suffered by the digestive system.

The enteric nervous system (ENS) is a complex neural network embedded in the gut wall that orchestrates the reflex behaviors of the intestine. The ENS is often referred to as the “little brain” in the gut because the ENS is more similar in size, complexity and autonomy to the central nervous system (CNS) than other components of the autonomic nervous system. Like the brain, the ENS is composed of neurons that are surrounded by glial cells. Enteric glia are a unique type of peripheral glia that are similar to astrocytes of the CNS. Yet enteric glial cells also differ from astrocytes in many important ways. The roles of enteric glial cell populations in the gut are beginning to come to light and recent evidence implicates enteric glia in almost every aspect of gastrointestinal physiology and pathophysiology. However, elucidating the exact mechanisms by which enteric glia influence gastrointestinal physiology and identifying how those roles are altered during gastrointestinal pathophysiology remain areas of intense research. The purpose of this e-book is to provide an introduction to enteric glial cells and to act as a resource for ongoing studies on this fascinating population of glia. Table of Contents: Introduction / A Historical Perspective on Enteric Glia / Enteric Glia: The Astroglia of the Gut / Molecular Composition of Enteric Glia / Development of Enteric Glia / Functional Roles of Enteric Glia / Enteric Glia and Disease Processes in the Gut / Concluding Remarks / References / Author Biography

The book will highlight the role played by glial cells in the central and peripheral nervous systems in both healthy and unhealthy individuals. Among all processes involved, we will discuss the importance of the enteric nervous system in the control of gut homeostasis, in the interaction with the immune system, and its participation in pathological conditions such as metabolic syndrome. We will also look at the relevance of astrocytes during synaptic transmission and the regulation of plasticity by releasing gliotransmitters. Ultimately, we will highlight the influence of astrocytes during the development of a number of neurodegenerative diseases, such as multiple sclerosis and Alzheimer’s disease, focusing on how the serum levels of the astrocytic protein S100B can be used as a biomarker for clinical decisions.

A practical guide to perioperative cognitive disorders, the most common complications of anesthesia and surgery in older people.

This book offers one of the most comprehensive reviews in the field of gastrointestinal (GI) physiology, guiding readers on a journey through the complete digestive tract, while also highlighting related organs and glandular systems. It is not solely limited to organ system physiology, and related disciplines like anatomy and histology, but also examines the molecular and cellular processes that keep the digestive system running. As such, the book provides extensive information on the molecular, cellular, tissue, organ, and system levels of functions in the GI system. Chapters on the roles of the gut as an endocrine, exocrine and neural organ, as well as its microbiome functions, broaden readers’ understanding of the multi-organ networks in the human body. To help illustrate the interconnections between the physiological concepts, principles and clinical presentations, it outlines clinical examples such as pathologies that link basic science with clinical practice in special “clinical correlates” sections. Covering both traditional and contemporary topics, it is a valuable resource for biomedical students, as well as healthcare and scientific professionals.

Intestinal homeostasis is key to control uptake across the mucosa and protect from harmful substances. Disturbances in the bidirectional communication between the gut and the brain are implicated in irritable bowel syndrome (IBS) and inflammatory bowel diseases (IBD), being Crohn’s disease (CD) and ulcerative colitis (UC) the two most common IBD subtypes. Although these chronic bowel-relapsing inflammatory disorders present different histopathology, they share similar pathological features. Both IBS and IBD are characterized by a disrupted intestinal barrier function, a pro-inflammatory chronic condition, and an altered gut-brain axis. Despite all the scientific effort, the sequence or exact combination of events that drive these diseases are still unknown, and so is the exact role of every single component. Growing evidence suggests altered neuro-immune interactions as a pathogenic factor. The general aim of this thesis was to elucidate the potential involvement of mast cells and eosinophils in IBS and IBD, and the neuro-immune intercellular circuit via vasoactive intestinal polypeptide (VIP) that might exacerbate mucosal inflammation and intestinal barrier disruption. Intestinal tissues from IBS, inactive IBD, healthy controls (HC), and murine colitis were collected. Electrophysiological and permeability studies were performed using the ex vivo Ussing chamber technique. Tissues were processed with immunohistological procedures to study cell numbers, activation, location, and interactions in relation to VIP. We demonstrated for the very first time an increased transcellular passage of live commensal and pathogenic bacteria through the colonic mucosa of IBS, identifying VIP as a key regulatory molecule together with mast cells activation. In vitro experiments revealed the ability of VIP to activate mast cells. Image analysis identified VIP-mast cells in closer proximity in IBD patients and murine colitis compared to controls. Communication between mast cells and VIP was shown upregulated in IBD and mice colitis via VIP receptor (VPAC)1. Similarities and differences between HC, IBS, and IBD were further studied. Results indicated a pronounced increased intestinal permeability in UC, even during remission, followed by IBS, compared to healthy controls. Surprisingly, permeability results did not correlate with mast cells, but with eosinophil number and activation. A further image analysis suggested an inhibitory effect of eosinophils and VIP on mast cells and an altered interaction between them under inflammatory conditions. Lastly, intestinal VIP levels were shown to increase in IBD patients after the treatment with biological agents and were suggested as a possible biomarker for biological treatment outcome. This thesis presents novel insights into the regulation of intestinal permeability, as well as into the pathophysiology of IBD and IBS by demonstrating the importance of neuro-immune interactions between mast cells, VIP, and eosinophils. Altogether, our findings have broadened the knowledge of neuro-immune interactions in IBS and IBD and might have the potential to onsight lead to new therapeutic approaches thereby improving the outcomes for patients suffering from these diseases.

The gastrointestinal tract is a long, muscular tube responsible for the digestion of food, assimilation of nutrients and elimination of waste. This is achieved by secretion of digestive enzymes and absorption from the intestinal lumen, with different regions playing specific roles in the processing of specific nutrients. These regions come into play sequentially as ingested material is moved along the length of the GI tract by contractions of the muscle layers. In some regions like the oesophagus transit it rapid and measured in seconds while in others like the colon transit is measured in hours and even days, commensurate with the relative slow fermentation that takes place in the large bowel. An hierarchy of controls, neural and endocrine, serve to regulate the various cellular targets that exist in the gut wall. These include muscle cells for contraction and epithelial cells for secretion and absorption. However, there are complex interactions between these digestive mechanisms and other mechanisms that regulate blood flow, immune function, endocrine secretion and food intake. These ensure a fine balance between the ostensibly conflicting tasks of digestion and absorption and protection from potentially harmful ingested materials. They match assimilation of nutrients with hunger and satiety and they ensure that regions of the GI tract that are meters apart work together in a coordinated fashion to match these diverse functions to the digestive needs of the individual. This ebook will provide an overview of the neural mechanisms that control gastrointestinal function. Table of Contents: Neural Control of Gastrointestinal Function / Cells and Tissues / Enteric Nervous System / From Gut to CNS: Extrinsic Sensory Innervation / Sympathetic Innervation of the Gut / Parasympathetic Innervation of the Gut / Integration of Function / References

Homeostatic Control of Brain Function offers a broad view of brain health and diverse perspectives for potential treatments, targeting key areas such as mitochondria, the immune system, epigenetic changes, and regulatory molecules such as ions, neuropeptides, and neuromodulators. Loss of homeostasis becomes expressed as a diverse array of neurological disorders. Each disorder has multiple comorbidities - with some crossing over several conditions - and often disease-specific treatments remain elusive. When current pharmacological therapies result in ineffective and inadequate outcomes, therapies to restore and maintain homeostatic functions can help improve brain health, no matter the diagnosis. Employing homeostatic therapies may lead to future cures or treatments that address multiple comorbidities. In an age where brain diseases such as Alzheimer's or Parkinson's are ever present, the incorporation of homeostatic techniques could successfully promote better overall brain health. Key Features include · A focus on the homeostatic controls that significantly depend on the way one lives, eats, and drinks. · Highlights from emerging research in non-pharmaceutical therapies including botanical medications, meditation, diet, and exercise. · Incorporation of homeostatic therapies into existing basic and clinical research paradigms. · Extensive scientific basic and clinical research ranging from molecules to disorders. · Emerging practical information for improving homeostasis. · Examples of homeostatic therapies in preventing and delaying dysfunction. Both editors, Detlev Boison and Susan Masino, bring their unique expertise in homeostatic research to the overall scope of this work. This book is accessible to all with an interest in brain health; scientist, clinician, student, and lay reader alike.