Juraj Harmatha - Academia.edu (original) (raw)
Papers by Juraj Harmatha
Chemicke Listy, Nov 15, 2021
European Journal of Clinical Investigation, 2015
Proceedings for Annual Meeting of The Japanese Pharmacological Society, 2018
Physiological Research, 2015
The effect of three therapeutically used drugs and five polyphenolic compounds on the mechanism o... more The effect of three therapeutically used drugs and five polyphenolic compounds on the mechanism of oxidative burst was compared in whole blood and isolated neutrophils at cellular and molecular level. In 10 μM concentration, the compounds investigated decreased the oxidative burst of whole blood in the rank order of potency: N-feruloylserotonin (N-f-5HT) > curcumin (CUR) > quercetin (QUER) > arbutin (ARB) > resveratrol (RES) > dithiaden (DIT) > carvedilol (CARV) > brompheniramine (BPA). The ratio between the percentage inhibition of extracellular versus intracellular chemiluminescence (CL) followed the rank order QUER > N-f-5HT > RES > CUR > DIT and is indicative of the positive effect of the compounds tested against oxidative burst of neutrophils, demonstrating suppression of reactive oxygen species extracellularly with minimal alteration of intracellular reactive oxygen species (ROS). Activation of protein kinase C was significantly decreased by DI...
Chemischer Informationsdienst, 1983
Die Verwendung von Diethylamin zum Schutz der α‐Exomethylengruppe in natürlichen Sesquiterpen‐ry‐... more Die Verwendung von Diethylamin zum Schutz der α‐Exomethylengruppe in natürlichen Sesquiterpen‐ry‐lactonen wird untersucht.
Chemischer Informationsdienst, 1976
Aufgrund von IR‐, massen‐ und NMR‐spektroskopischen Untersuchungen und Vergleichen werden die dre... more Aufgrund von IR‐, massen‐ und NMR‐spektroskopischen Untersuchungen und Vergleichen werden die drei Haupt‐Sesquiterpen‐Komponenten, die aus dem Petrol‐ äther‐Extrakt von Homogyne alpina(L.)Cass.
Fitoterapia, Jan 22, 2015
Our previous research on immunostimulatory properties of trilobolide and its structurally related... more Our previous research on immunostimulatory properties of trilobolide and its structurally related natural analogues isolated from Laser trilobum (L.) Borkh., encouraged us to investigate structurally related guaianolides belonging to a specific group of sesquiterpene lactones with characteristic glycol moiety attached to the lactone ring. Ever increasing attention has been paid to certain guaianolides such as thapsigargin and trilobolide for their promising anti-inflammatory, anticancer, anti-infectious and SERCA inhibitory activities. However, due to their alkylation capabilities, they might be cytotoxic. Search for compounds with preserved immunobiological properties and decreased cytotoxicity led us to transform some of their structural features, particularly those related to their side chain functionality. For this reason, we prepared a series of over 20 various deacylated, acyl modified, or relactonized derivatives of trilobolide. The immunobiological effects were screened in v...
Tetrahedron, 1994
ABSTRACT
ChemInform, Aug 18, 2010
ABSTRACT
Journal of Chromatographic Science, 2005
European Journal of Pharmacology, 2008
Cytokine, 2009
ABSTRACT Sesquiterpene lactones (SLs) are a varied group of secondary plant metabolites, occurrin... more ABSTRACT Sesquiterpene lactones (SLs) are a varied group of secondary plant metabolites, occurring widely within the families Asteraceae and Apiaceae. SLs, including recognized agents such as artemisin, costunolide and helenalin, are inhibitors of NF-j B activation. This effect explains suppressive effects of SLs on immune-stimulated cytokine and nitric oxide (NO) production. There are exceptions from this rule. We have found recently that thapsigargin (TG), a SL isolated from Thapsia garganica (L.), enhances biosynthesis of NO. The prominent feature of TG biological activities is the inhibition of sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) leading to elevation of intracellular calcium. The SERCA is also inhibited by trilobolide (TB), SL isolated from Laser trilobum (L.) Borkh. We analyzed the effects of these agents on production of NO and IFN-c under in vitro conditions using rat and mouse resident peritoneal cells (rPECs; mPECs), and human peripheral blood mononuclear cells (hPBMCs). They were cultured in complete RPMI-1640 medium (2 � 106/mL). Supernatant levels of IFN-c were determined by ELISA, the NO production by animal PECs by Griess reagent. Possible contamination of the SL samples with LPS was excluded using the Limulus amoebocyte assay. Both TG and TB considerably enhanced production of NO by rPECs, while marginal and no effect on NO production was observed in mPECs and hPBMCs, respectively. Both TB and TG were effective to enhance the IFN-c secretion in rPECs and hPBMCs at 40- and 400-nM concentrations, respectively. The effect was dose dependent, the highest IFN-c content (2–3 ng/mL) being reached at the interval of 24 h with the 10-lM dose, irrespective of the type of SLs. Activation of IFN-c was not suppressed by calcium chelating agents BAPTA/AM and TMB-8. The immunostimulatory mode of action of TG and TB is thus unlikely to result from their intracellular calcium enhancing effects.
Journal of Chromatography A, 1989
Cheminform, 2010
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Collection of …, 1993
... 28972906 [Abstract]; Zdenko Procházka, Juris E. Ancans, Jiřina Slaninová, Alena Machová, Tom... more ... 28972906 [Abstract]; Zdenko Procházka, Juris E. Ancans, Jiřina Slaninová, Alena Machová, Tomislav Barth, Jana kopková, Milo Buděínský, Frantika Pavlíková and Michal Lebl Synthesis and properties of analogues of vasopressin with 1-aminocyclopropane-1-carboxylic ...
Chemicke Listy, Nov 15, 2021
European Journal of Clinical Investigation, 2015
Proceedings for Annual Meeting of The Japanese Pharmacological Society, 2018
Physiological Research, 2015
The effect of three therapeutically used drugs and five polyphenolic compounds on the mechanism o... more The effect of three therapeutically used drugs and five polyphenolic compounds on the mechanism of oxidative burst was compared in whole blood and isolated neutrophils at cellular and molecular level. In 10 μM concentration, the compounds investigated decreased the oxidative burst of whole blood in the rank order of potency: N-feruloylserotonin (N-f-5HT) > curcumin (CUR) > quercetin (QUER) > arbutin (ARB) > resveratrol (RES) > dithiaden (DIT) > carvedilol (CARV) > brompheniramine (BPA). The ratio between the percentage inhibition of extracellular versus intracellular chemiluminescence (CL) followed the rank order QUER > N-f-5HT > RES > CUR > DIT and is indicative of the positive effect of the compounds tested against oxidative burst of neutrophils, demonstrating suppression of reactive oxygen species extracellularly with minimal alteration of intracellular reactive oxygen species (ROS). Activation of protein kinase C was significantly decreased by DI...
Chemischer Informationsdienst, 1983
Die Verwendung von Diethylamin zum Schutz der α‐Exomethylengruppe in natürlichen Sesquiterpen‐ry‐... more Die Verwendung von Diethylamin zum Schutz der α‐Exomethylengruppe in natürlichen Sesquiterpen‐ry‐lactonen wird untersucht.
Chemischer Informationsdienst, 1976
Aufgrund von IR‐, massen‐ und NMR‐spektroskopischen Untersuchungen und Vergleichen werden die dre... more Aufgrund von IR‐, massen‐ und NMR‐spektroskopischen Untersuchungen und Vergleichen werden die drei Haupt‐Sesquiterpen‐Komponenten, die aus dem Petrol‐ äther‐Extrakt von Homogyne alpina(L.)Cass.
Fitoterapia, Jan 22, 2015
Our previous research on immunostimulatory properties of trilobolide and its structurally related... more Our previous research on immunostimulatory properties of trilobolide and its structurally related natural analogues isolated from Laser trilobum (L.) Borkh., encouraged us to investigate structurally related guaianolides belonging to a specific group of sesquiterpene lactones with characteristic glycol moiety attached to the lactone ring. Ever increasing attention has been paid to certain guaianolides such as thapsigargin and trilobolide for their promising anti-inflammatory, anticancer, anti-infectious and SERCA inhibitory activities. However, due to their alkylation capabilities, they might be cytotoxic. Search for compounds with preserved immunobiological properties and decreased cytotoxicity led us to transform some of their structural features, particularly those related to their side chain functionality. For this reason, we prepared a series of over 20 various deacylated, acyl modified, or relactonized derivatives of trilobolide. The immunobiological effects were screened in v...
Tetrahedron, 1994
ABSTRACT
ChemInform, Aug 18, 2010
ABSTRACT
Journal of Chromatographic Science, 2005
European Journal of Pharmacology, 2008
Cytokine, 2009
ABSTRACT Sesquiterpene lactones (SLs) are a varied group of secondary plant metabolites, occurrin... more ABSTRACT Sesquiterpene lactones (SLs) are a varied group of secondary plant metabolites, occurring widely within the families Asteraceae and Apiaceae. SLs, including recognized agents such as artemisin, costunolide and helenalin, are inhibitors of NF-j B activation. This effect explains suppressive effects of SLs on immune-stimulated cytokine and nitric oxide (NO) production. There are exceptions from this rule. We have found recently that thapsigargin (TG), a SL isolated from Thapsia garganica (L.), enhances biosynthesis of NO. The prominent feature of TG biological activities is the inhibition of sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) leading to elevation of intracellular calcium. The SERCA is also inhibited by trilobolide (TB), SL isolated from Laser trilobum (L.) Borkh. We analyzed the effects of these agents on production of NO and IFN-c under in vitro conditions using rat and mouse resident peritoneal cells (rPECs; mPECs), and human peripheral blood mononuclear cells (hPBMCs). They were cultured in complete RPMI-1640 medium (2 � 106/mL). Supernatant levels of IFN-c were determined by ELISA, the NO production by animal PECs by Griess reagent. Possible contamination of the SL samples with LPS was excluded using the Limulus amoebocyte assay. Both TG and TB considerably enhanced production of NO by rPECs, while marginal and no effect on NO production was observed in mPECs and hPBMCs, respectively. Both TB and TG were effective to enhance the IFN-c secretion in rPECs and hPBMCs at 40- and 400-nM concentrations, respectively. The effect was dose dependent, the highest IFN-c content (2–3 ng/mL) being reached at the interval of 24 h with the 10-lM dose, irrespective of the type of SLs. Activation of IFN-c was not suppressed by calcium chelating agents BAPTA/AM and TMB-8. The immunostimulatory mode of action of TG and TB is thus unlikely to result from their intracellular calcium enhancing effects.
Journal of Chromatography A, 1989
Cheminform, 2010
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Collection of …, 1993
... 28972906 [Abstract]; Zdenko Procházka, Juris E. Ancans, Jiřina Slaninová, Alena Machová, Tom... more ... 28972906 [Abstract]; Zdenko Procházka, Juris E. Ancans, Jiřina Slaninová, Alena Machová, Tomislav Barth, Jana kopková, Milo Buděínský, Frantika Pavlíková and Michal Lebl Synthesis and properties of analogues of vasopressin with 1-aminocyclopropane-1-carboxylic ...