PharmDr. Andrej Kováč, PhD
The main research focus is on blood-brain barrier (BBB), the layer of endothelial cells forming the vessel/capillary wall in the brain. Recently, the BBB is considered to be a part of a highly dynamic system called the neurovascular unit (NVU), consisting of vascular cells, glial cells, and neurons. An important area of research in NVU studies is the investigation of damage and dysfunction in different diseases. Our aim is to investigate changes in NVU in a group of neurodegenerative diseases called tauopathies. Tauopathies represent a heterogeneous group of neurodegenerative diseases characterized by abnormal deposition of the microtubule-associated protein tau in cells of the nervous system (neurons and glial cells). In collaboration with Dr. Maria Deli from the Institute of Biophysics, Hungarian Academy of Sciences in Szeged we have developed in vitro BBB model based on the culture of cerebral endothelial cells, astrocytes and pericytes. We showed that exposure of brain endothelial cells to tau protein does not evoke any significant responses. However, when glial cells were present, inflammatory mediators produced by these cells, such as NO, cytokines and chemokines, significantly modified endothelial properties such as transendothelial electrical resistance and permeability for small molecules (Kovac et al., 2009).
The second area of interest deals with an attractive topic – biomarkers. Biomarkers are objective, quantifiable characteristics of physiological or pathological processes in the human body. We are interested in discovering molecular biomarkers (proteins or metabolites) that help diagnose, and predict treatment response or prognosis of Alzheimer’s disease and other tauopathies. We are using several state-of-the-art approaches such as ultrasensitive immunoassays, quantitative and qualitative proteomics, peptidomics and metabolomics. At this time, we have in operation four LC-MS systems – one single quad, one ion trap, two triple quads and matrix-assisted laser desorption/ionization-time of flight mass spectrometer (MALDI-Tof/Tof). We have developed several new analytical methods for quantification of different metabolites in animal and human biological fluids such as neurotransmitters (Kovac et al.,2014), thiols (Kovac et al.,2014) and markers of the immune system (Galba et al., 2016).
The group has intensive national and international collaborations. These include the cooperation with Prof. William Banks at the University of Washington (Seattle, USA), where Dr. Kováč worked as a postdoc and learned techniques of measuring the blood-brain barrier permeability in vivo, with Prof. Yoichi Morofuji at the University of Nagasaki (Nagasaki, Japan), with Dr. Maria Deli at the Biological Research Institute in Szeged (Hungary), and with Assoc. Prof. David Friedecky at the Medical University in Olomouc (Czech Republic).
- Ing. Jozef Hanes, PhD
- MSc. Petra Majerová, PhD
- Ing. Eva Stevens, PhD
- PharmDr. Alena Michalicová (PhD student)
- MSc. Sandra Mihaljevic (PhD student)
- Prof. PharmDr. Josef Jampílek, PhD.
Projects – funding
- The blood-brain barrier (BBB) is a selective barrier formed by the endothelial cells that line cerebral microvessels. The project is focused on the one of the most important parts of brain research, on BBB. It is focused on development of novel transporting vectors for neuropharmaceuticals.
- APVV grant no. 14-0547
- Duration: 2015 – 2018
- The aim of the project is to characterize the extent of the blood-brain barrier damage of transgenic rat models in neurodegeneration caused by tau protein and to compare the results of different lines of transgenic animals.
- VEGA 2/0159/15
- Duration: 2015 – 2018
PublicationsGalba, J., Michalicova, A., Parrak, V., Novak, M., Kovac, A. Quantitative analysis of phenylalanine, tyrosine, tryptophan and kynurenine in rat model for tauopathies by ultra-high performance liquid chromatography with fluorescence and mass spectrometry detection. (2016) J Pharm Biomed Anal. Jan 5;117:85-90
Bencurova, E., Kovac, A., Pulzova, L., Gyuranecz, M., Mlynarcik, P., Mucha, R., Vlachakis, D., Kossida, S., Flachbartova, Z., Bhide, M. Deciphering the protein interaction in adhesion of Francisella tularensis subsp. holarctica to the endothelial cells (2015) Microbial Pathogenesis, 81, pp. 6-15.
Mlynarcik, P., Pulzova, L., Bencurova, E., Kovac, A., Dominguez, M.A., Hresko, S., Bhide, M.R. Deciphering the interface between a CD40 receptor and borrelial ligand OspA (2015) Microbiological Research, 170, pp. 51-60.
Kovac A, Svihlova K, Michalicova A, Novak M. Liquid Chromatography-Tandem Mass Spectrometry Method for Determination of Homocysteine in Rat Plasma: Application to the Study of a Rat Model for Tauopathies. J Chromatogr Sci. (2014)
Kovac, A., Somikova, Z., Zilka, N., Novak, M. Liquid chromatography-tandem mass spectrometry method for determination of panel of neurotransmitters in cerebrospinal fluid from the rat model for tauopathy(2014) Talanta, 119, pp. 284-290.
Shah, G.N., Price, T.O., Banks, W.A., Morofuji, Y., Kovac, A., Ercal, N., Sorenson, C.M., Shin, E.S., Sheibani, N. Pharmacological inhibition of mitochondrial carbonic anhydrases protects mouse cerebral pericytes from high glucose-induced oxidative stress and apoptosis (2013) Journal of Pharmacology and Experimental Therapeutics, 344 (3), pp. 637-645.
Pulzova, L., Kovac, A., Mucha, R., Mlynarcik, P., Bencurova, E., Madar, M., Novak, M., Bhide, M. OspA-CD40 dyad: Ligand-receptor interaction in the translocation of neuroinvasive Borrelia across the blood-brain barrier (2011) Scientific Reports, 1, art. no. 86.
Kovac, A., Erickson, M.A., Banks, W.A. Brain microvascular pericytes are immunoactive in culture: Cytokine, chemokine, nitric oxide, and LRP-1 expression in response to lipopolysaccharide (2011) Journal of Neuroinflammation, 8, art. no. 139.
Kovac, A., Zilka, N., Kazmerova, Z., Cente, M., Zilkova, M., Novak, M. Misfolded truncated protein τ induces innate immune response via MAPK pathway (2011) Journal of Immunology, 187 (5), pp. 2732-2739.
Kovac, A., Zilkova, M., Deli, M.A., Zilka, N., Novak, M. Human truncated tau is using a different mechanism from amyloid-β to damage the blood-brain barrier (2009) Journal of Alzheimer’s Disease, 18 (4), pp. 897-906.