Biological activities of natural products
About the research project
We study the biological properties and anti-cancer activity of two groups of natural products isolated from plants at the Department of Biochemistry, Faculty of Medicine, Masaryk University, Brno (prof. RNDr. Eva Táborská, CS.c – alkaloids; Mgr. Jiří Slanina, Ph.D., lignans):
1. Quaternary benzo[c]phenanthridine alkaloids (QBAs) are a relatively small group of isoquinoline alkaloids with attractive biological activities. They are produced by a number of plant species of Papaveraceae, Fumariaceae and Rutaceae families. Extracts from some plants containing QBAs are used in folk medicine as antimicrobial, antifungal and anti-inflammatory agents. Importantly, QBAs also display anti-proliferative activities against cancer cell lines. All QBAs are intensively coloured (from yellow to dark red) and display fluorescence properties. The chromophores responsible for fluorescence are highly condensed aromatic rings with electron-donor substituents containing oxygen.
In our laboratory we study the antiproliferative, proapoptotic and antioxidative properties of following QBA: sanguinarine (SA), chelerythrine (CHE), macarpine (MA), sanguirubine (SR), chelirubine (CHR), sanguilutine (SL) and chelilutine (CHL). We also study fluorescence properties of alkaloids and their possible use as fluorescence probes. All tested alkaloids can enter living cells and MA, CHR and SA can bind DNA. Fluorescence microscopy of MA, CHR and SA -stained cells reveals nuclear architecture and clearly defines chromosomes and apoptotic fragments in living cells. Moreover, MA staining can rapidly report the cellular DNA content of living cells at a resolution level adequate for cell cycle analysis. We have patented the possibility of using MA as supravital fluorescent DNA probe both in fluorescence microscopy and flow cytometry, including multiparameter analysis of peripheral blood and bone marrow.
2. Dibenzo[a,c]cyclooctadiene lignans originated from fruit of Schisandra chinensis used in traditional Chinese medicine as a tonic, antitussive, treatment of lung, heart, and kidney afflictions, as well as a range of other conditions such as chronic asthma, spontaneous sweating, palpitation, diabetes, insomnia and forgetfulness. Schisandra is also clinically prescribed in China for the treatment of hepatitis. It was reported that Schisandra lignans gomisin A, schisandrin B, schisandrin A and B, and schisantherin A can inhibit multidrug resistance-associated proteins MRP1 and P-glycoprotein. In our laboratory we study the effects on multidrug resistance and the anti-proliferative activities of the following lignans: schizandrin, gomisin A, gomisin N, gomisin J, angeloylgomisin H, tigloylgomisin P, deoxyschizandrin, ? -schizandrin and wuweizisu C.