How Intestinal Motility Activates Sensory Pathways
Funder
National Health and Medical Research Council
Funding Amount
$555,875.00
Summary
Pain and discomfort from the gut are common and unpleasant. We understand how gut sensory nerve cells work, at the cellular, molecular and genetic level. However, movement of the gut wall and contents are the major cause of activation of sensory neurons. We know little about which particular patterns of movement cause pain. This is crucial information for accurately diagnosing human gut disorders, for monitoring effectiveness of treatments and for identifying potential new drug targets.
Characterisation Of Erusiolin - A New Peptide Hormone
Funder
National Health and Medical Research Council
Funding Amount
$547,202.00
Summary
Obesity and type II diabetes are epidemic diseases in Australia. Gut-derived hormones are key mediators in these diseases, due to their role in regulating appetite and blood glucose levels. Therapeutic modulation of these hormones also provides significant benefits for patients. In this proposal, we will determine the metabolic functions, such as appetite control, for a previously uncharacterised hormone, which is an unexplored therapeutic target for obesity and diabetes.
Mechanical Factors In Normal Human Colonic Motility
Funder
National Health and Medical Research Council
Funding Amount
$650,023.00
Summary
Abnormal human colonic contractions cause significant medical, societal and financial burdens. Diagnosis and treatment of motility disorders requires an understanding of normal colonic contractility against which to measure dysfunction. Through state-of-the-art recording and analytical techniques, developed by the applicants, this project will provide the first clear description of normal human colonic motor patterns and how they are generated.
Glucose is a critical fuel for living organisms and its presence in the gut triggers nerves that slow stomach emptying. However, little is known of how glucose is actually detected in the gut. We have established that sweet taste molecules of the tongue are also present in the gut, where they may detect glucose. This research will measure the expression and function of these molecules in the gut of humans and mice, and reveal key information on their potential as targets in health and disease.
Stimulant laxatives are widely used and usually very effective in the short term, but how they work is very poorly understood. Our recent work has shown that they selectively excite sensory pathways from the colon which then trigger defaecation. This points to an undiscovered mechanism that potently affects colonic sensation and motility. This is likely to be a target for new treatments for other colonic disorders such as Irritable bowel syndrome and faecal incontinence.
Bitter Taste As A Mediator Of Food Intake And Postprandial Glycaemia In Health And Type 2 Diabetes
Funder
National Health and Medical Research Council
Funding Amount
$735,430.00
Summary
The gut “tastes” contents passing through it in a similar manner to the tongue. Recent evidence suggests that bitter substances in the gut can reduce appetite and slow the emptying of meals from the stomach, by stimulating gastrointestinal hormone release. We propose studies to understand how this system functions in health and type 2 diabetes, and whether it can be targeted to provide new diabetes treatments
How Does Inflammation Of The Gut Change Its Sensory Innervation?
Funder
National Health and Medical Research Council
Funding Amount
$613,767.00
Summary
A large number of patients that are referred to gastroenterologists for pain and discomfort from the bowel are offered no effective treatment. This has a large impact on quality of life and often involves invasive tests to rule out inflammatory or cancerous causes. These patients are classified as suffering from irritable bowel syndrome (IBS). Patients who have diagnosable inflammatory bowel disease (IBD) where colonoscopy is positive may suffer similar symptoms but also have no treatment for th ....A large number of patients that are referred to gastroenterologists for pain and discomfort from the bowel are offered no effective treatment. This has a large impact on quality of life and often involves invasive tests to rule out inflammatory or cancerous causes. These patients are classified as suffering from irritable bowel syndrome (IBS). Patients who have diagnosable inflammatory bowel disease (IBD) where colonoscopy is positive may suffer similar symptoms but also have no treatment for this type of symptom. It is becoming apparent that a large subgroup of IBS patients have undergone prior infection or inflammation, and that there are in fact changes in the types of cells in biopsies from their gut. Thus there are common features to IBS and inflammation. These may provide a means for us to find new treatments for IBS and IBD symptoms. Mice develop similar microscopic changes in the colon after experimental inflammation to those seen in humans, so we can discover more from this model. We have recently established that there are several types of sensory nerve fibres from the mouse colon and rectum that convey information about contractions, distension and chemical mediators released from tissue to the central nervous system. These are almost certainly responsible for generating symptoms in patients. We aim in this project to discover how these sensory nerves change in their responsiveness to mechanical and chemical stimuli in experimental inflammation. Importantly we shall investigate the mediators that are present in the tissue which may activate sensory nerves and-or the receptors on sensory nerves that may be increased. These experiments we hope will provide a target at which to aim novel drug treatments for symptoms of IBS and IBD.Read moreRead less
The migration of cancer cells (metastasis) is responsible for most cancer deaths. Central to this is dynamic organisation of the actin cytoskeleton _ an internal structure that provides cell shape and enables movement. We have identified a family of small molecules (called miR-200) that regulates this actin cytoskeleton through specifically downregulating various genes. We are investigating the nature of these genes and their role in cell motility _ an underlying pre-requisite of metastasis.