Role of Annexin A2 in the regulation of fibrinolysis in alcohol induced liver inhury

Summary

To delineate the mechanisms of action of alcohol induced ANXA2 mediated fibrinolysis in vivo mouse models of alcohol induced liver injury.

Supervisor(s)

Dr Devanshi Seth

Research Location

Centenary Institute of Cancer Medicine and Cell Biology

Program Type

Masters/PHD

Synopsis

Alcoholic liver disease (ALD) is a complex multistep disease process that progresses through stages of alcoholic steatosis, alcoholic hepatitis and alcoholic cirrhosis. Using DNA microarray we recently identified over-expression of molecules involved in plasmin homeostasis including pro-fibrinolytic annexin A2 (ANXA2), p11, tissue plasminogen activator (tPA), plasminogen (PLG) and anti-fibrinolytic plasminogen activator inhibitor (PAI-1) in human ALD.1,2 In in vitro cell culture and in vivo mouse models of alcohol this was accompanied by increased fibrinolysis and plasmin activity.3 Alcohol metabolism inhibitor abrogated ANXA2 and p11.3 In addition, alcohol increased plasmin activity and fibrinolysis was significantly inhibited with ANXA2 antibody. ANXA2-p11 heterotetramer is known to act as a receptor for tPA and PLG to generate plasmin and regulate fibrinolysis. Plasmin has been implicated in tissue remodelling and fibrinolysis and may play a role in regulating fibrogenic responses in alcohol induced liver injury. Hypothesis Alcohol contributes to liver injury, in part, by regulating fibrinolysis and plasmin activity mediated via ANXA2. Research Plan Rationale: We have compelling evidence based on the information generated from our human and in vitro data and preliminary in vivo experiments that there is a role for ANXA2-mediated liver injury. This project aims to extend these observations in physiologically relevant mice models of acute and chronic alcohol to investigate the mechanism of liver fibrosis through regulation of fibrinolysis. We aim to determine/investigate in acute and chronic alcohol mice models:

• Fibrinolysis related gene expression profiles.
• Fibrinolysis activity and fibrosis.
• The effect of knock down of ANXA2 on fibrinolysis.

1. Seth et al. Am J Path 2003, 163(6): 2303-2317. 2. Seth et al. J Hepatol 2006, 45:306-320. 3. Seth et al. 2006. Alcoholism: Clinical & Experimental Research. 30 (9): 61A: 208.

Additional Information

Following techniques will be used in the project:

• In vitro and in vivo: cell lines, primary cell culture, animal handling, alcohol administration
• RNA and protein: Q-PCR, immunohistochemistry, Western blotting, flow cytometery, ELISA, Microarray, proteomics.
• Knockdown studies: RNAi, antibody inhibition
• Functional assays: fibrinolysis, plasmin activity, triglyceride
• Microscopy, imaging, histology, quantitation of fibrosis
• Animal handling and alcohol administration

Dr Seth has expertise in alcohol related liver injury, alcohol mouse models, molecular biology, functional assays and data analysis. She has supervised and co-supervised PhD students (University of Western Australia, University of Sydney) and Honours students (USYD). Prof Paul Haber is well known in the area of alcoholic liver injury and animal models of alcoholic liver injury. He will provide clinical expertise to this project. Prof Philip Hogg is a leading expert in fibrinolysis and will provide support as an ongoing collaborator. Outcomes and significance of the project: This project will identify and dissect the mechanism(s) of alcohol mediated ANXA2 and its role as a physiological fibrinolytic regulator in liver injury. The strength of this project is to consolidate the earlier findings in human, in vitro, and in vivo animal models to obtain an insight in the processes of early effects of alcohol in the acute alcohol mouse model through to progressive development of liver injury in the chronic alcohol mouse model.

Keywords

Alcoholic liver disease, alcoholic hepatitis, alcoholic steatosis, liver injury, hepatic fibrosis, Annexin A2, acute alcohol, fibrinolysis, plasmin, PAI-1, RNAi, blocking antibody, alcohol mouse models, expression analysis, Liver & hormonal disorders, Therapeutics & adverse drug effects, Health & lifestyle, Human body

Opportunity ID

The opportunity ID for this research opportunity is: 250

Other opportunities with Dr Devanshi Seth

• Significance of Osteopontin and its splice variants in alcoholic liver disease