Methods of screening for compounds that modulate TAFIa activity, compounds, and methods of using the compounds
Provided are methods of screening compounds for any aspirin-related activity other than TAFI inhibition, and also for non-inhibition of TAFI. Compounds identified by the screening methods can be used to treat, prevent or manage in a patient pain, fever, colon cancer, pancreatic cancer or an inflammatory, platelet aggregation, fibrinolytic or hemorrhagic disease or disorder. Also provided is a method of evaluating test compounds for TAFI inhibitory activity wherein the TAFI inhibitory activity of these test compounds is compared to the TAFI inhibitory activity of aspirin or its derivatives or metabolites. Further provided is a method of treating, preventing or managing in a patient, a hemorrhagic or thrombotic disease or disorder with high dose aspirin or aspirin derivatives or metabolites. Also contemplated is a method of treating, preventing or managing in a patient, pain, fever, colon cancer, pancreatic cancer or an inflammatory, platelet aggregation, fibrinolytic or hemorrhagic disease or disorder comprising administering aspirin or a derivative thereof or any other therapeutic having at least one desired therapeutic or prophylactic activity of aspirin to a patient in need thereof and administering to the patient a factor that promotes TAFIa activity, e.g. stabilized TAFIa, to ameliorate one or more adverse side effects of the therapeutic. Compounds identified by the methods of the invention are also provided.
1. A method of identifying a compound which possesses (i) at least one aspirin activity selected from the group consisting of COX-1 inhibition and COX-2 inhibition, and (ii) no TAFIa-inhibition, comprising the steps of:
a) exposing TAFIa to the test compound;
b) measuring carboxypeptidase activity of TAFIa in the presence of and in the absence of the test compound;
c) determining whether the test compound inhibits carboxypeptidase activity of TAFIa and/or inhibits TAFI activation by measuring the level of carboxypeptidase activity of TAFIa during exposure to the test compound; and
d) determining whether at least one aspirin activity is retained by the test compound, thereby identifying a compound that possesses at least one aspirin activity but not TAFIa-inhibitory activity.
2. The method of claim 1 , wherein the aspirin activity is COX-2 inhibition.
3. The method of claim 1 , wherein the aspirin activity is COX-1 inhibition.
4. A method of evaluating inhibition of TAFIa activity by a test compound, in comparison with aspirin, salicylic acid, salicyluric acid or gentisic acid, comprising the steps of:
a) exposing TAFIa to the test compound;
b) measuring carboxypeptidase activity of TAFIa in the presence of and in the absence of the test compound;
c) measuring the level of inhibition of carboxypeptidase activity of TAFIa by the test compound;
d) exposing TAFIa to aspirin, salicylic acid, salicyluric acid or gentisic acid;
e) measuring the level of inhibition of carboxypeptidase activity of TAFIa by aspirin, salicylic acid, salicyluric acid or gentisic acid; and
f) comparing the level of inhibition of carboxypeptidase activity of TAFIa by the test compound to the level of inhibition of carboxypeptidase activity of TAFIa by aspirin, salicylic acid (SA), salicyluric acid (SU) or gentisic acid,
thereby determining whether the test compound inhibits TAFIa activity more or less than aspirin, salicylic acid, salicyluric acid or gentisic acid.
5. The method of claim 4 , wherein step (a) further comprises preincubating TAFIa and the test compound for at least about 20 minutes.
6. The method of claim 4 , wherein (b), (c), and (e) are carried out using a clot lysis assay.
7. The method of claim 4 , wherein (b), (c), and (e) are carried out using a fibrinogen assay.
8. The method of claim 4 , wherein (b), (c), and (e) are carried out using a plasminogen capture assay.
9. The method of claim 4 , wherein (b), (c), and (e) comprise using a fluorescent based assay.