Gastrointestinal System – Overview

Abstract

The gastrointestinal tract is a highly organized and complex system to help digestion and absorption of nutrients through the integration of neuronal, endocrine, and immunological functions. Several chapters addressed the important aspects in the current understanding of the pathophysiology, symptoms, and pharmacological approaches to treat gastrointestinal (GI) motility disorders that are frequent and often cause considerable distress and impaired quality of life. Prokinetic drugs are widely prescribed to treat GI motility disorders. The term prokinetic was used in the context of the GI tract to refer to a group of drugs that stimulate GI motility or transit of luminal contents. The stimulatory effect of these drugs on GI motility is clinically relevant in the management of GI disorders associated with GI motility such as gastroparesis, functional dyspepsia, intestinal pseudo-obstruction, constipation, functional bowel diseases, and nausea and vomiting. The goal of the prokinetic drugs is to improve motility and relieve symptoms. As the regulation of GI motility is complex, the pathogenesis of GI disorders is multifactorial and the primary targets of the prokinetic drugs also vary ranging from the central nervous system to the enteric nervous system, enteric immune system, and gut microbiota. Several diseases result from the compromised function of the epithelial barrier. Several chapters cover the broad aspects of “leaky” gut, including microbial dysbiosis and mechanisms of diarrhea. Finally, pharmacology of liver disease is addressed from the point of liver cirrhosis and microbial therapy.