Understanding The Relationship Of Incretin Hormones, Gastric Emptying And Reactive Hypoglycaemia
Funder
National Health and Medical Research Council
Funding Amount
$132,743.00
Summary
Low blood glucose levels following a meal occur frequently in otherwise healthy people and those who have had surgery for weight loss. It affects quality of life adversely and current management is unsatisfactory. The proposed studies will use sophisticated techniques to evaluate the roles of the rate of stomach emptying and the so-called 'incretin' hormones which stimulate the release of insulin after a meal. The outcomes will have major implications for more rational management.
Mechanics Of Normal And Disordered Gastric Emptying Studied Using Simultaneous Ultrasound And High Resolution Manometry
Funder
National Health and Medical Research Council
Funding Amount
$145,626.00
Summary
Optimal digestion and absorption relies on the stomach breaking down food and delivering it to the small intestine at an optimal rate. Abnormalities in the processes controlling the stomach's processing of food may lead to malnutrition, gastrointestinal symptoms or unpredictable drug absorption, and are commonly seen in patients with diabetes mellitus, gastrointestinal reflux disease and nonulcer dyspepsia, or following stomach surgery. Currently our understanding of the way the stomach empties ....Optimal digestion and absorption relies on the stomach breaking down food and delivering it to the small intestine at an optimal rate. Abnormalities in the processes controlling the stomach's processing of food may lead to malnutrition, gastrointestinal symptoms or unpredictable drug absorption, and are commonly seen in patients with diabetes mellitus, gastrointestinal reflux disease and nonulcer dyspepsia, or following stomach surgery. Currently our understanding of the way the stomach empties food is incomplete, and there is little information as to the mechanisms by which diseases cause abnormal stomach emptying. Recent developments in recording methods mean that we can now simultaneously measure stomach contractions, the pressures these generate and flow from the stomach. This information is synchronised and displayed for analysis using computer techniques. In this project these novel methods will be used initially to examine the normal processes by which meals with a variety of compositions and consistencies empty from the stomach. This will provide information as to which aspects of the way the stomach functions are important for breaking down food into particles, and which aspects control the flow of food from the stomach into the intestine. The mechanisms by which the rate of emptying of the stomach is controlled by feedback signals caused by the presence of foodstuffs in the small intestine will be investigated by examining the effects of infusing nutrients into the intestine on the motions of the stomach wall, pressures within the stomach and the passage of stomach contents into the small intestine. The mechanism of action of drugs and diseases which slow stomach emptying will then be examined by measuring the movements, pressures and emptying of the stomach in subjects receiving the drug, or in patients with dibetes, and comparing this information with the processes observed during normal stomach emptying.Read moreRead less
Relationships Between Diet And Gastric Motor Function In Functional Dyspepsia
Funder
National Health and Medical Research Council
Funding Amount
$220,500.00
Summary
Functional dyspepsia (FD) is a condition characterised by abdominal symptoms without a cause that is identifiable by conventional diagnostic tests. Symptoms (eg fullness, bloating) are frequently induced by eating. 20 - 40 % of the adult population in Western countries are affected by FD, and the condition, therefore, represents a considerable financial burden to the health care system. FD affects quality of life adversely. In many people with FD, stomach contractions and the 'sensitivity' of th ....Functional dyspepsia (FD) is a condition characterised by abdominal symptoms without a cause that is identifiable by conventional diagnostic tests. Symptoms (eg fullness, bloating) are frequently induced by eating. 20 - 40 % of the adult population in Western countries are affected by FD, and the condition, therefore, represents a considerable financial burden to the health care system. FD affects quality of life adversely. In many people with FD, stomach contractions and the 'sensitivity' of the stomach are abnormal. Often, people with FD avoid fatty foods in the belief that these cause or exacerbate symptoms. There is, however, little information about the potential role of dietary habits in causing symptoms, the relationship between eating and disturbances in stomach function, and the impact of dietary changes on symptoms. Our previous studies suggest an important role for nutrients, particularly fat, in FD. We will address the hypothesis that dietary factors, particularly fat intake, have substantial implications for the pathophysiology and treatment of FD. Our studies will involve physiological (stomach emptying, appetite and food intake) and epidemiological (dietary habits, dyspeptic symptoms and quality of life-related aspects) measurements. The subjects-patients with FD will receive standardised test meals of varying nutrient composition, and we will study the effects on their stomach and on symptoms. We will also test some medications in an attempt to alleviate symptoms during and after food ingestion, particularly after fatty foods. Other studies will assess the dietary habits of patients with FD in relation to symptom occurrence and investigate the possibility that dietary intervention (reduction of fat content in the diet, exclusion of offending foods) will benefit these patients. The proposed studies will provide the most comprehensive studies to date of the relationship between symptoms in patients with FD with dietary habits and stomach function.Read moreRead less
Modulating Gastrointestinal Function For Control Of Diabetes
Funder
National Health and Medical Research Council
Funding Amount
$883,469.00
Summary
It is now recognized that gastrointestinal function, particularly the rate that meals empty from the stomach, and the secretion of hormones from the small intestine in response to nutrients, is fundamental to blood glucose control in people with diabetes. This project seeks to understand how these processes can best be modified by dietary or pharmaceutical means to improve blood glucose control and thereby prevent complications in type 2 diabetes
Cooperative Motor Control Of The Pyloric Junction By Myogenic And Neuronal Mechanisms
Funder
National Health and Medical Research Council
Funding Amount
$271,527.00
Summary
The coordinated muscle movement in the junction between the stomach and small intestine is an essential mechanism for controlling the speed of gastric content moving into the intestine for further digestion. The muscle movement determines the gastric emptying at an optimal rate and prevents intestinal contents reflux to the stomach. Failure of this coordination is likely to be involved in a variety of clinical conditions including accelerated or delayed gastric emptying. Up to date, little infor ....The coordinated muscle movement in the junction between the stomach and small intestine is an essential mechanism for controlling the speed of gastric content moving into the intestine for further digestion. The muscle movement determines the gastric emptying at an optimal rate and prevents intestinal contents reflux to the stomach. Failure of this coordination is likely to be involved in a variety of clinical conditions including accelerated or delayed gastric emptying. Up to date, little information is available about the interaction between nerve, muscle and pacemaker cells during this coordinated movement. In this project, we will investigate how the nerve, muscle and pacemaker cells work together to control this coordinated movement. We will study this mechanism at both cellular and organ levels and try to establish the patterns of muscle movement and their coordination between the stomach and the small intestine. The interaction between the nerve and pacemaker cells will be characterised in these studies. Our work will provide structural evidence for this activity. It includes identification of the nerve pathways connecting between the small intestine and stomach and determination of whether the pacemaker cell network is an uniform continuous or a discontinuous or a transitional structure across the junction. These studies will reveal the correlation between pacemaker cell mediated activity and the density of these cells in each junctional region. We will also determine whether the difference in propagation activity across the junction is due to differences in the number of cells for signal conduction or electrical connections between the cells. This study will advance our knowledge for understanding how the nerve, muscle and pacemaker cells work in concert in this junction, which is an important step for further clinical investigation of related disease.Read moreRead less
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.