The influence of displacement compounds on the binding of ochratoxin A to human serum albumin examined with fluorescence anisotropy methods

The subject of the research is the application of the methods of fluorescence anisotropy measurements to study the interaction between human serum albumin (HSA) and toxins and selected medicines (ibuprofen, warfarin, flurbiprofen). Optical spectroscopic methods are useful tools for the study of biologically active compounds. Determining binding intensity of ochratoxin A (OTA) to albumin may be helpful in explaining the effects of toxic influence of OTA. The main factor influencing the distribution of OTA is its affinity for plasma proteins. It was shown that ochratoxin binds strongly to albumin. By the use of the method of fluorescence anisotropy it was proved that the unbound fraction of OTA is higher due to competing interactions with drugs. As a result of separating ochratoxin from protein by competitive compounds, a decrease in the fluorescence anisotropy of the HSA-OTA complex was observed. The largest increase in free fraction of OTA is caused by flurbiprofen, then ibuprofen and warfarin. It will accelerate OTA transport to target organs and shortening its half-life period, leading consequently to a decrease in chronic toxic effects.