Department of Pharmacology

Activities of the Department of Pharmacology are governed by scientific aims of the ”Human Health” programme. The ultimate goal is the research and development of original low-molecular weight drugs targeting immune-related diseases. The hitherto obtained results have demonstrated immunosuppressive properties of newly synthesized derivatives of pyrimidine, and immunobiological activities of compounds of natural origin. Advanced studies are focused on the analysis of rational chemical structures and synthesis of compounds. They should facilitate transfer of experimental data to preclinical and clinical phases of research, and to commercial practice. Optimization of the structure is ensured by an immediate backward communication between chemical and biological teams of the project. An indispensable part of the studies is the determination of the safety and mechanism of drug action. The therapeutic potential of promising drug candidates is assessed using experimental models of autoimmune and inflammatory human diseases.

1. Development of novel immunomodulatory drugs

We have found that sesquiterpene lactones of natural origin, thapsigargin (Tg) and trilobolide (Tb) possess immunostimulatory activity. Tg exhibits promising anticancer effects. The present study describes the method of detection of cellular uptake and intracellular distribution of these compounds. We found that Tb localizes in the endoplasmic reticulum of various cancer cell lines. The results are rational standpoint for further design of synthetic drug forms.

Collaboration: Institute of Chemical Technology in Prague

Localization of sarco-endoplasmic reticulum Ca2+ ATP-ase (SERCA) inhibitor trilobolide in cancer cells. Presence of trilobolide in the cells from osteosarcoma(U-2 OS, upper row) and from prostatic carcinoma (PC-3, lower row) was detected by means of its conjugation with “Bodipy” (A+D; green). Endoplasmic reticulum was labelled by ER-Tracker™ Red (B+E; red). The merge ofthese figures (C+F) proves the accumulation of trilobolide in endoplasmic reticulum.

Publication:
Jurášek M, Rimpelová S, Kmoníčková E, Drašar P, Ruml T, (2014): Tailor-made fluorescent trilobolide to study its biological relevance. J. Med. Chem. 57(19): 7947-7954. IF 5.480

2. Novel compounds with anti-inflammatory properties

Original poly-substituted derivatives of pyrimidine were synthesized. Their immunobiological properties were investigated using murine peritoneal cells. In dependence on the structure, the compounds proved to be inhibitors of immune-activated production of inflammatory mediators such as nitric oxide and prostaglandin E2. They are well tolerated, without signs of cytotoxicity. The compounds are candidates for treatment of chronic inflammatory diseases.

Collaboration: Institute of Organic Chemistry and Biochemistry AS CR, v.v.i.

A. C4,6-hydroxy derivatives lack inhibitory activity. B. The intrinsic potential to suppress the production of nitric oxide (NO) and prostaglandin E2 (PGE2) is acquired by substitution of hydroxy groups with chlorine. C. Inhibitory activity is further enhanced by the replacement of 2-amino group with the (dimethylamino) methylenamino one. D. Concentrations inhibiting the NO production by 50% (IC50) are approximately 5 μM.

Publications:

Jansa P, Holý A, Dračínský M, Kolman V, Janeba Z, Kostecká P, Kmoníčková E, Zídek Z, (2014): 5-Substituted 2-amino-4,6-dihydroxy- pyrimidines and 2-amino-4,6-dichloropyrimi dines: synthesis and inhibitory effects on imm- une-activated nitric oxide production. Med. Chem. Res. 23(10): 4482-4490. IF 1.612

Jansa P, Holý A, Dračínský M, Kolman V, Janeba Z, Kmoníčková E, Zídek Z, (2014): Synthesis and structure–activity relationship studies of polysubstituted pyrimidines as inhibitors of immune-activated nitric oxide production. Med. Chem. Res., DOI: 10.1007/s00044-014-1285-5. IF 1.612

Research and development of immunomodulatory drugs

In the development of new drugs is occupied by low molecular weight substances such as pyrimidine derivatives. We analyzed a large amount of newly synthesized original structures in terms of their internal immunological properties. Depending on their chemical structure, they are found to inhibit the production of prostaglandins, nitric oxide and cytokines. Based on these results, we decided to monitor their antiinflammatory effects, in experimental models of human diseases, such as ulcerative colitis and rheumatoid arthritis. In vivo experiments have confirmed the assumption of anti-inflammatory activity of some derivatives.

 

A number of pyrimidine derivatives were found to be prominent inhibitors of mediators of inflammation such as nitric oxide (NO) and prostaglandin E2 (PGE2). The screening was performed under in vitro conditions using mouse macrophages. The concentrations that inhibited production of inflammatory mediators by 50% (IC50) were within the range of 2 µM to 10 µM. The compounds were devoid of cytotoxic activities.

 

Pyrimidine derivatives exhibit beneficial effects on the development of experimental colitis induced in mouse by dextran sulphate. The inhibitory effect is fully comparable to the effect of a common standard, i.e. clinically widely employed sulfasalazine.

 

Collaboration: ÚOCHB Praha

Publications: Harmatha, J., Buděšínský, M.,, Vokáč, K., Kostecká, P., Kmoníčková, E., Zídek, Z.: Trilobolide and related sesquiterpene lactones from Laser trilobum possessing immunobiological properties. Fitoterapia, 89C: 157-166, 2013. IF 2.231.
Jansa, P., Holý, A., Dračínský, M., Kolman, V., Janeba, Z., Kostecká, P., Kmoníčková, E., Zídek, Z.: 5-Substituted 2-amino-4,6-dihydroxypyrimidines and 2-amino-4,6-dichloropyrimidines: synthesis and inhibitory effects on immune-activated nitric oxide production. Medicinal Chemistry Research, (in press). IF 1.612.