Alcoholic Chronic Pancreatitis: Induction, Progression And Reversal
Funder
National Health and Medical Research Council
Funding Amount
$632,211.00
Summary
Pancreatitis (inflammation of the pancreas) is a serious complication of alcohol abuse. Patients suffer from severe and often intractable abdominal pain, maldigestion and diabetes, We have recently shown that gut toxins (endotoxins) may act as a trigger factor for pancreatitis in alcoholics. The proposed project aims to characterise the effects of gut toxins on the pancreas during alcohol abuse so as to identify pathways that may be therapeutically targeted to prevent or retard the disease.
Alcoholic Pancreatitis : Role Of Alcohol, Endotoxin And Stellate Cells
Funder
National Health and Medical Research Council
Funding Amount
$501,653.00
Summary
The pancreas is the major digestive organ of the body. It contains many proteins (enzymes) which break down food. One of the more serious complications of alcohol (ethanol) abuse is pancreatitis, a condition that has both acute and chronic manifestations. Patients with acute pancreatitis suffer from acute abdominal pain; in severe cases the condition can be fatal. Repeated attacks of acute pancreatitis can lead to chronic pancreatitis, a condition in which, normal pancreatic tissue is lost and i ....The pancreas is the major digestive organ of the body. It contains many proteins (enzymes) which break down food. One of the more serious complications of alcohol (ethanol) abuse is pancreatitis, a condition that has both acute and chronic manifestations. Patients with acute pancreatitis suffer from acute abdominal pain; in severe cases the condition can be fatal. Repeated attacks of acute pancreatitis can lead to chronic pancreatitis, a condition in which, normal pancreatic tissue is lost and is replaced by scarring. This disease causes chronic pain, inability to digest food with consequent malnutrition and destruction of the insulin producing cells of the gland leading to diabetes. The mechanisms by which alcohol causes pancreatitis are not yet known. Although it is well established that the risk of developing pancreatitis increases with increasing intake of alcohol, suggesting that alcohol exerts toxic effects on the gland, it is also clear that not all alcoholics develop pancreatitis, indicating that an additional trigger factor-susceptibility factor is required to produce overt disease. The proposed project aims to determine the mechanisms responsible for alcohol-induced acute and chronic pancreatitis. It seeks i) to determine whether toxins from gut bacteria (endotoxins) may act as the trigger factor for acute alcoholic pancreatitis; and ii) to characterise the effects of alcohol and endotoxin on the cells responsible for pancreatic scarring, namely, pancreatic stellate cells. Our experiments will involve an animal model of alcohol feeding as well as pancreatic cells grown in dishes (cultured cells). Identification of the pathways by which alcohol causes pancreatic injury may enable the development of treatment strategies to prevent and-or retard the progress of alcoholic pancreatitisRead moreRead less
Acute pancreatitis is an acute abdominal inflammatory process (the pancreas attempts to digest itself) with significant mortality in those patients having the severe form of the disease. The commonest causes of the disease are gallstones and excessive alcohol consumption. Approximately 80% of patients with acute pancreatitis recover, but 20% experience the severe form of the disease. In severe pancreatitis, 30% of patients die. Severe pancreatitis is associated with necrosis (cell death) of the ....Acute pancreatitis is an acute abdominal inflammatory process (the pancreas attempts to digest itself) with significant mortality in those patients having the severe form of the disease. The commonest causes of the disease are gallstones and excessive alcohol consumption. Approximately 80% of patients with acute pancreatitis recover, but 20% experience the severe form of the disease. In severe pancreatitis, 30% of patients die. Severe pancreatitis is associated with necrosis (cell death) of the pancreas which, results from reduced blood flow in the organ. This reduced blood flow may be secondary to increased pressure in the pancreatic duct following occlusion of the duct. Preliminary studies suggest that the reason why the pancreas may be susceptible to necrosis is the anatomical arrangement of its blood supply, being made up of many end arterioles (very small arteries) that do not connect with other arteries. The consequence of this arrangement is that if a particular end arteriole becomes blocked, the area of the tissue cannot obtain a blood supply from neighbouring arterioles (as in other organs). Blood supply is partly controlled by nerves. The nerve transmitter nitric oxide is one of the major chemicals involved in this regulation. Nitric oxide also regulates the pressure in the pancreatic duct by acting on the sphincter of Oddi, situated at the opening of the pancreatic duct. Consequently, the action of nitric oxide during pancreatitis may be crucial to the development of the severe disease. This proposal seeks to define the blood supply of the pancreas, its regulation, the effect that increased pancreatic duct pressure has on it and the role that nitric oxide plays in this. If the hypotheses regarding the role of nitric oxide on pancreatic blood flow is proven, then drugs which influence nitric oxide levels can be used to limit the production of pancreatic necrosis. In turn, such an effect will reduce the mortality and morbidity of acute pancreatitis.Read moreRead less
Understanding The Pathogenesis And Heterogeneity Of Autoimmunity As Failure Of Multiple Steps
Funder
National Health and Medical Research Council
Funding Amount
$504,023.00
Summary
Autoimmune diseases like diabetes, thyroid disease or rheumatoid arthritis affect around 1 in 15 people in Australia. It is clear that defects in a number of different genetic mechanisms can contribute to the development of autoimmunity. But it is currently not clear how these different mechanisms need to interact to prevent the onset of disease. This grant seeks to understand these interactions and how defects in two or more tolerance mechanisms can lead to autoimmunity.
Extracellular Acidification And Its Role In Disease
Funder
National Health and Medical Research Council
Funding Amount
$371,529.00
Summary
This proposal focuses on the diseases cystic fibrosis and acute pancreatitis for which there are currently no treatments. In both diseases the affected organs become strongly acidic. Furthermore, these acid changes can be causal in disease progression. However, the source of this acidification is remains unknown. We will identify the routes of acid secretion, the causal role of acidification in disease progression and the effectiveness of treatments aimed at restoring acid-base balance.
Design And Development Of Small Molecules To Regulate Protease Activated Receptor Type 2
Funder
National Health and Medical Research Council
Funding Amount
$439,500.00
Summary
A new class of proteins have been discovered on the surface of cells. These are activated by enzymes known as proteases and are therefore called Protease Activated Receptors (PARs). PARs appear to be very important 'sensors' of proteases outside cells, becoming activated in response to very low concentrations of proteases. This suggest that proteases may exert some of their biological effects through these receptors, which are now implicated in a growing number of diseases (e.g. thrombosis, card ....A new class of proteins have been discovered on the surface of cells. These are activated by enzymes known as proteases and are therefore called Protease Activated Receptors (PARs). PARs appear to be very important 'sensors' of proteases outside cells, becoming activated in response to very low concentrations of proteases. This suggest that proteases may exert some of their biological effects through these receptors, which are now implicated in a growing number of diseases (e.g. thrombosis, cardiovascular disorders, asthma, inflammatory bowel disease, Crohn's disease, pancreatitis, stomach and colon cancer, arthritis, and there may also be a role in wound healing). We are working towards dissecting the roles for one of these receptors (PAR2) in disease by developing small molecules for selective binding to this receptor. We will particularly distinguish between compounds that can activate (agonists) or deactivate (antagonists) the receptor. These experiments will involve computer-assisted compound design, structural comparisons between small molecules with activity and those without, and cellular studies designed to measure affinity, activation and deactivation of PAR2. The outcome will be a series of small molecules that bind tightly to the PAR2 receptor and have a well defined function (antagonist, agonist, partial agonist). While the above studies are in progress some peptides that are known to activate this receptor will be examined in rodent models of human disease (airways inflammation, pancreatitis, stomach and colon cancer, arthritis). Studies like this have been very revealing for us in the past (Nature 1999, 398, 156-160 A protective role for protease-activated receptors in the airways). Then the designed and developed compounds will also be examined for signs of therapeutic potential. The work will provide a better understanding of how this receptor works and a clearer picture of the role of this receptor in human disease.Read moreRead less