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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Animals, Antibodies, Monoclonal, Binding Sites, Carrier Proteins, Cholesterol Ester Transfer Proteins, Cholesterol Esters, Cricetinae, Cricetulus, Female, Glycoproteins, Lipoproteins, HDL.
user
Does wiedendiol-A inhibit cholesteryl ester binding to its transfer protein? Context: To study the wiedendiol-A (W-A) inhibition mechanism of plasma cholesteryl ester (CE) transfer protein (CETP) on the transfer of CE. Using gel filtration method. W-A at 30 mumol.L-1 inhibited association of CE with CETP by 76% and CETP transfer activity by 81%. In addition, W-A enhanced binding of TP2, a monoclonal antibody with a CETP C-terminal epitope which is involved in CE binding, to CETP, suggesting a W-A-induced conformational change at the epitope for increased TP2 binding. When CETP activity was measured by varying high-density lipoproteins (HDL) concentration, the apparent Vmax of CE transfer was inhibited by 74% and 83% in the presence of W-A at 14 and 25 mumol.L-1, respectively, while the apparent K(m) of HDL for CETP did not change.
assistant
W-A action is mediated through interaction between W-A and CETP, but not through those between W-A and lipoproteins. Final Decision: yes