Students' Research Circle    
 
 
2022
2021
Call for papers
The conference
» Veterinary Session
Veterinary Jury
Biology Session
Sponsors
Awards-list
2020
2019
2018
2017
2016
2015
2014
2013
2012
2011
2010
2009
2008
2007
2006
2005
2004
2003
2002
Home » Archive » 2021 » Veterinary Session

Veterinary session

Optimisation of microsomal studies to test pharmaceutical candidate compounds
Szentkirályi-Tóth Anna - year 5
University of Veterinary Medicine Budapest, Department of Pharmacology and Toxicology
Supervisor: Pásztiné Dr. Erzsébet Gere

Abstract:

Trypsin-like serine proteases are enzymes that take part in numerous physiological and pathological mechanisms of the body, thus their inhibition exerts a significant impact on the efficient management of several malignacies such as neoplastic or viral diseases. In our research, we studied the effects of four matriptase/TMPRSS2 inhibitory (MI) 3-amidinophenylalanine-derived compounds such as MI-432, MI-463, MI-482 and MI-1900 on the activities of cytochrome P450 (CYP) izoenzymes (CYP1A2, CYP2C9, CYP2C19 and CYP3A4) of microsomes from different species (human, rat, beagle and cynomolgus monkey), and we also determined and compared the microsomal depletion percentages of the 3-amidinophenylalanine-derived compounds between species using ultrapressure liquid chromatography method coupled with mass spectrometry.

During microsomal CYP1A2 activity measurements it was detected that fluorescent intensities were significantly reduced by the administration of MI-463 and MI-1900 in rat, by that of MI-432 and MI-482 in beagle, and by that of each used inhibitor in cynomolgus monkey. According to our research data, 3-amidinophenilalanine-derived compounds at 50 µM did not influence the function of human microsomal CYP1A2, CYP2C9 and CYP2C19, however, all four applied MI compounds inhibited the activity of CYP3A4 significantly, half maximal inhibitory concentration (IC50) values remained below 1 µM (MI-432: 0,39 µM± 0,09 µM, MI-463: 0,21 µM± 0,03 µM, MI-482: 0,30 µM± 0,07 µM, MI-1900: 0,63 µM± 0,04 µM).

Studying the depletion percentages of the MI compounds using human microsomes, it was observed that MI-432 and MI-1900 were decomposed to the highest extent, and we also discovered a significant difference between the depletion percentages of MI-463 and MI-1900 and MI-482 and MI-1900. Based on interspecies comparisons between monkey and beagle microsomes it was found that there were significant differences in the CYP1A2-mediated biotransformation of MI-482, but not in that of MI-432, MI-463 or MI-1900.

In conslusion, it was confirmed that 3-amidinophenilalanine-derived compounds with in vitro antiviral effect had a species-dependent inhibitory effect on some isoenzymes (CYP1A2 and CYP3A4), which may require further in vivo studies to predict drug interaction potentials in the future.



List of lectures