Publication Date

Spring 5-2023


School of Health Sciences


Biology: Biomedical Sciences


Irritable Bowel Syndrome, Brain-gut Axis, visceral hypersensitivity, serotonin signaling, permeability, motility, gut microbiota, pathophysiology, inflammation, Gastrointestinal Tract, physiology, HPA-axis, mechanism


Digestive System Diseases | Medical Pathology | Medical Physiology | Nutritional and Metabolic Diseases | Pathological Conditions, Signs and Symptoms


Irritable bowel syndrome (IBS) is a disease of the gastrointestinal tract affecting approximately 11-21% of people worldwide (Xiao et al., 2021). This research focuses on the dysregulation of gut homeostasis in IBS and explains how the pathophysiology of the gut is controlled by the bidirectional brain-gut axis. The mechanisms of the brain-gut axis consist of neuro-immune cross talk, neuro-hormone cross talk, microbiome-gut signaling, and the HPA-axis. Each of these contribute to one or more of the possible phenotypes of gut pathophysiology, which could include intestinal permeability, visceral hypersensitivity, and motility disturbance (Xiao et al., 2021). Stress is also an important peripheral contributor to IBS through many of these mechanisms, especially the hypothalamic-pituitary-adrenal (HPA)-axis (Camilleri et al., 2012). The goal of this research is to present a more comprehensive pathophysiology of IBS to give a better foundation for future research and treatment. This thesis is limited to and relies on previously published primary research but will link together underlying causes of IBS within the brain-gut axis to propose manners of future targeted treatments.