Tag Archives: furin

Influence of organic solvents on the furin activity

T. V. Osadchuk1, O. V. Shybyryn1, A. V. Semyroz1, V. K. Kibirev1,2

1Institute of Bioorganic Chemistry and Petrochemistry, National Academy of Sciences of Ukraine, Kyiv;
2Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: osadchuk@bpci.kiev.ua

Furin belongs to a family of calcium-dependent serine proprotein convertases, which transform the inactive protein precursors into mature polypeptides. In model experiments, we studied the effect of organic solvents such as acetone, dimethyl sulfoxide (DMSO), dioxane, isopropanol and ethanol on the furin activity. Furin was found to retain up to 88% of its initial activity in the presence of DMSO, whereas in the presence of acetone only 30%. Organic solvents formed the following decreasing sequence of their effects on furin: acetone> isopropanol> ethanol> dioxane> dimethyl sulfoxide. The relationship between the residual furin activity and solvent parameters such as relative polarity, dipole moment and log P were investigated. The effect of the organic solvent appeared not to correlate with any of the listed characteristics. Laidler-Sсatchard’s graphs, which according to a theory must be linear, demostrated non-linearity. These results indicate that not only electrostatic interactions play an important role in the studied enzymatic reaction but also other factors, e.g. hydrophobic contacts, hydrogen bonds can influence furin catalysis. This seems relevant for further research in this area.

Synthesis and investigation of the derivatives of amidinohydrazonelated aromatic compounds as furin inhibitors

T. V. Osadchuk1, A. V. Semyroz1, O. V. Shybyryn1, V. K. Kibirev1,2

1Institute of Bioorganic Chemistry and Petrochemistry, National Academy of Sciences of Ukraine, Kyiv;
2Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: osadchuk@bpci.kiev.ua

The proprotein convertase furin plays a crucial role in a variety of pathogenic processes such as cancer, bacterial and viral diseases, neurodegenerative disorders and diabetes. Thus, furin inhibitors are promi­sing therapeutics for the treatment of many diseases. In this study we synthesized some new non-peptide of furin inhibitors, with positively charged amidinohydrazone groups present in ortho-, meta– or para-positions in the benzene rings relative to the linker. From the results of biological testing it followed that the position of amidinohydrazone groups in aromatic rings was significant for the manifestation of antifurin activity. The replacement of linkers containing a propoxy group by a “bridge” with a benzene ring was found to cause an increase in the inhibitory effect of the compounds. The effect of synthesized bisamidinohydrazones on furin also depended on the substitution of the hydrogen atom in the amidinohydrazone group by the methyl group. These compounds were shown to block the enzyme activity mainly by the mechanism of mixed inhibition, and their Ki values were at the micromolar level.

Influence of cations on furin activity

T. V. Osadchuk1, O. V. Shybyryn1, A. V. Semyroz1,
O. M. Bondarenko1, V. K. Kibirev1,2

1Institute of Bioorganic Chemistry and Petrochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: osadchuk@bpci.kiev.ua;
2Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv

Furin is the most studied proprotein convertase which processes inactive protein precursors, converting them into biologically active polypeptides. We have investigated cation effects of cesium, strontium, cadmium, iron, cobalt and nickel on the furin activity. It was shown that in the presence of Ca2+ (1 mM) these ions were able to activate the enzyme, and the peak position of its activity depends on the nature of the ion. Particularly, for Fe2+ it was observed at the ion concentration of 15 mM, whereas for Cd2+, Co2+ and Ni2+ the maximum activity of furin was at 20 mM, for Cs+ the peak was at a concentration of 30 mM, and for strontium ions it was 40 mM. The affinity of the cations for furin was estimated by Lineweaver-Burk plots for low concentrations of ions for the ascending branch of furin activity dependence on the cation concentration. It was found that their affinity in comparison with Ca2+ was sharply reduced (~ 18-150 times). The studied cations (under physiological conditions) were shown not to be able to compete with calcium ions for furin, and in natural environment they cannot influence its activity.

Chemical structure and properties of low-molecular furin inhibitors

T. V. Osadchuk1, O. V. Shybyryn1, V. K. Kibirev1,2

1Institute of Bioorganic Chemistry and Petrochemistry,
National Academy of Sciences of Ukraine, Kyiv;
2Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: osadchuk@bpci.kiev.ua

The review is devoted to the analysis of the relationship between a chemical structure and properties of low-molecular weight inhibitors of furin, the most studied proprotein convertase, which is involved in the development of some pathologies, such as oncologic diseases, viral and bacterial infections, etc. The latest data concerning the influence of peptides, pseudo-peptides, aromatic and heterocyclic compounds, some natural ones such as flavonoids, coumarins, and others on enzyme inactivation are considered. The power of furin inhibition is shown to rise with the increasing number of positively charged groups in the structure of these compounds. Peptidomimetics (Ki = 5-8 pM) are shown to be the most effective furin inhibitors. The synthesized substances, however, have not been used in practical application yet. Nowadays it is very important to find more selective inhibitors, improve their stability, bioavailability and safety for the human organism.

Study on derivatives of 5-amino-4-acylamino-1H-pyrazole as inhibitors of furin

V. K. Kibirev1, T. V. Osadchuk1, O. B. Vadzyuk2,
O. V. Shablykin1, O. P. Kozachenko1, S. A. Chumachenko1,
S. V. Popilnichenko1, V. S. Brovarets1

1Institute of Bioorganic Chemistry and Petrochemistry,
National Academy of Sciences of Ukraine, Kyiv;
е-mail: kibirev@bpci.kiev.ua;
2Palladin Institute of Biochemistry, National Academy
of Sciences of Ukraine, Kyiv

A series of 5-amino-1H-pyrazoles was synthesized and studied as inhibitors of furin. The most potent compound, 5-amino-4-acetylamino-3-(4-methylphenylamino)-1H-pyrazole, was found to retard the activity of furin by mixed-type inhibition with Ki = 288 µМ. These findings permit to plan new ways for chemical modifications of the 5-amino-1H-pyrazole structure and design more potent furin inhibitors of non-peptide nature.

Estimation of the ROS in the presence of biologically active substances by porous silicon fluorescence

V. B. Shevchenko1, O. I. Dacenko1, O. V. Shablykin2, T. V. Osadchuk2,
A. M. Lyakhov2, Y. V. Pivovarenko3, V. A. Makara1,3

1Taras Shevchenko Kyiv National University, Ukraine;
e-mail: shevchenko@univ.kiev.ua;
2Institute of Bioorganic Chemistry and Petroleum Chemistry,
National Academy of Sciences of Ukraine;
3STC Physico-Chemical Center of Materials Science
of Taras Shevchenko Kyiv National University and NAS of Ukraine

The fluorescence spectra of the porous silicon modified by water solutions of biologically active materials and materials of biological origin are recorded as well as the fluorescence spectra of the porous silicon modified by lecithin monolayers grown on the surface of water solutions of the biologically active materials. The analysis of the obtained spectra made it possible to conclude on the effect of the studied materials on the content of ROS.

Non-peptide furin inhibitors based on amidinohydrazones of diarylaldehydes

V. K. Kibirev1, T. V. Osadchuk2, O. P. Kozachenko2,
O. B. Vadzyuk1, V. S. Brovarets2

1Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: kinet@biochem.kiev.ua;
2Institute of Bioorganic Chemistry and Petrochemistry, National Academy of Sciences of Ukraine, Kyiv

A series of novel non-peptidic furin inhibitors containing amidinohydrazone moieties has been synthesized under interaction of dialdehydes, the derivatives of ethylene diethylvanillin ethers, with aminoguanidine bicarbonate. Two aryl cycles were bridged by 1,2-ethylene-, 1,4-buthylene- or 1,4-dimethylenebenzene-group. The compounds have been found to inhibit furin. The antifurin activity was shown to grow with the increase of the length and/or hydrophobicity of the bridge. The most potent compound, containing in the bridge the lypophylic benzene cycle was found to inhibit the activity of furin with Ki = 0.51 µM.

Furin inhibitors based on the derivatives of calix[4]arene CX3im

V. K. Kibirev1, T. V. Osadchuk2, R. V. Rodik3, V. I. Kalchenko3

1Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: kibirev@biochem.kiev.ua;
2Institute of Bioorganic Chemistry and Petrochemistry, National Academy
of Sciences of Ukraine, Kyiv;
3Institute of Organic Chemistry, National Academy of Sciences of Ukraine, Kyiv

The aim of this work was to study antifurin activity of some derivatives of calix[4]arenes modified on the upper rim of the macrocycle by positively charged or uncharged groups. It was found that calixarene CX3im­ derivatives containing positively charged N-methylimidazolium cycles were indeed able to inhibit furin (Ki = 58.2 μM). The magnitude of the effects depended also on the hydrophobicity of the substituents located on the lower rim of the macrocycle. The  findings indicated the possibility of creating furin inhibitors of new generation based on the calix[4]arene platform.

Synthesis, biological evaluation and docking of novel bisamidinohydrazones as NON-peptide inhibitors of furin

V. K. Kibirev1, T. V. Osadchuk2, O. P. Kozachenko2, V. Kholodovych3, O. D. Fedoryak2, V. S. Brovarets2

1Palladin Institute of Biochemistry,
National Academy of Sciences of Ukraine, Kyiv;
e-mail: kibirev@biochem.kiev.ua;
2Institute of Bioorganic Chemistry and Petrochemistry,
National Academy of Sciences of Ukraine, Kyiv;
3Rutgers University, Newark, USA

A series of novel non-peptidic furin inhibitors with values of inhibitory constants (Ki) in the range of 0.74-1.54 μM was obtained by interactions of aminoguanidine hydrocarbonate with three diaryldicarbaldehydes. Correspondingly p-hydroquinone, piperazine and adipic acid were used as linkers between their benzene moieties. Docking studies of these new inhibitors into recently published 3D-structure of human furin (PDB code 4OMC) showed that they were able to interact with subsites S1 and S4 of the enzyme. The overall arrangement of bisamidinohydrazones into furin active site was similar to the position of the ligand co-crystallized with a protease. Observations obtained with molecular modeling allowed further guidance into chemical modifications of the synthesized inhibitors which improve their inhibitory activity.