The aim of the study was to broadly determine the biological activities of purple potato ethanolic extract of the Blue Congo variety (BCE). The antioxidant activity of BCE was determined in relation to liposome membranes, and peroxidation was induced by UVB and AAPH. To clarify the antioxidant activity of BCE, we investigated its interactions with hydrophilic and hydrophobic regions of a membrane using fluorimetric and FTIR methods. Next, we investigated the cytotoxicity and pro-apoptotic activities of BCE in two human colon cancer cell lines (HT-29 and Caco-2) and in normal cells (IPEC-J2). In addition, the ability to inhibit enzymes that are involved in pro-inflammatory reactions was examined. Furthermore, BCE interactions with serum albumin and plasmid DNA were investigated using steady state fluorescence spectroscopy and a single molecule fluorescence technique (TCSPC-FCS). We proved that BCE effectively protects lipid membranes against the process of peroxidation and successfully inhibits the cyclooxygenase and lipoxygenase enzymes. Furthermore, it interacts with the hydrophilic and hydrophobic parts of lipid membranes as well as with albumin and plasmid DNA. It was observed that BCE is more cytotoxic against colon cancer cell lines than normal IPEC-J2 cells; it also induces apoptosis in cancer cell lines, but does not induce cell death in normal cells.

• MeSH
• albuminy MeSH
• antioxidancia chemie   farmakologie   MeSH
• fytogenní protinádorové látky chemie   farmakologie   MeSH
• inhibitory cyklooxygenasy chemie   farmakologie   MeSH
• inhibitory lipoxygenas chemie   farmakologie   MeSH
• lidé MeSH
• lipidy chemie   MeSH
• liposomy MeSH
• nádorové buněčné linie MeSH
• plazmidy MeSH
• reaktivní formy kyslíku MeSH
• rostlinné extrakty chemie   farmakologie   MeSH
• sérový albumin chemie   metabolismus   MeSH
• Solanum tuberosum chemie   MeSH
• vazba proteinů MeSH
• viabilita buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Based on the significant anti-inflammatory activity of natural quinone primin (5a), series of 1,4-benzoquinones, hydroquinones, and related resorcinols were designed, synthesized, characterized and tested for their ability to inhibit the activity of cyclooxygenase (COX-1 and COX-2) and 5-lipoxygenase (5-LOX) enzymes. Structural modifications resulted in the identification of two compounds 5b (2-methoxy-6-undecyl-1,4-benzoquinone) and 6b (2-methoxy-6-undecyl-1,4-hydroquinone) as potent dual COX/5-LOX inhibitors. The IC50 values evaluated in vitro using enzymatic assay were for compound 5b IC50 = 1.07, 0.57, and 0.34 μM and for compound 6b IC50 = 1.07, 0.55, and 0.28 μM for COX-1, COX-2, and 5-LOX enzyme, respectively. In addition, compound 6d was identified as the most potent 5-LOX inhibitor (IC50 = 0.14 μM; reference inhibitor zileuton IC50 = 0.66 μM) from the tested compounds while its inhibitory potential against COX enzymes (IC50 = 2.65 and 2.71 μM for COX-1 and COX-2, respectively) was comparable with the reference inhibitor ibuprofen (IC50 = 4.50 and 2.46 μM, respectively). The most important structural modification leading to increased inhibitory activity towards both COXs and 5-LOX was the elongation of alkyl chain in position 6 from 5 to 11 carbons. Moreover, the monoacetylation in ortho position of bromo-hydroquinone 13 led to the discovery of potent (IC50 = 0.17 μM) 5-LOX inhibitor 17 (2-bromo-6-methoxy-1,4-benzoquinone) while bromination stabilized the hydroquinone form. Docking analysis revealed the interaction of compounds with Tyr355 and Arg120 in the catalytic site of COX enzymes, while the hydrophobic parts of the molecules filled the hydrophobic substrate channel leading up to Tyr385. In the allosteric catalytic site of 5-LOX, compounds bound to Tyr142 and formed aromatic interactions with Arg138. Taken together, we identified optimal alkyl chain length for dual COX/5-LOX inhibition and investigated other structural modifications influencing COX and 5-LOX inhibitory activity.

• MeSH
• benzochinony chemie   MeSH
• inhibitory cyklooxygenasy chemická syntéza   chemie   farmakologie   MeSH
• inhibitory lipoxygenas chemická syntéza   chemie   farmakologie   MeSH
• katalytická doména MeSH
• oxidace-redukce MeSH
• počítačová simulace MeSH
• resorcinoly chemie   MeSH
• simulace molekulového dockingu MeSH
• spektrální analýza metody   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Publikační typ
• časopisecké články MeSH

A new series of 1,2-diaryl-4-substituted-benzylidene-5(4H)-imidazolone derivatives 4a-l was synthesized. Their structures were confirmed by different spectroscopic techniques (IR, 1 H NMR, DEPT-Q NMR, and mass spectroscopy) and elemental analyses. Their cytotoxic activities in vitro were evaluated against breast, ovarian, and liver cancer cell lines and also normal human skin fibroblasts. Cyclooxygenase (COX)-1, COX-2 and lipoxygenase (LOX) inhibitory activities were measured. The synthesized compounds showed selectivity toward COX-2 rather than COX-1, and the IC50 values (0.25-1.7 µM) were lower than that of indomethacin (IC50  = 9.47 µM) and somewhat higher than that of celecoxib (IC50  = 0.071 µM). The selectivity index for COX-2 of the oxazole derivative 4e (SI = 3.67) was nearly equal to that of celecoxib (SI = 3.66). For the LOX inhibitory activity, the new compounds showed IC50 values of 0.02-74.03 µM, while the IC50 of the reference zileuton was 0.83 µM. The most active compound 4c (4-chlorobenzoxazole derivative) was found to have dual COX-2/LOX activity. All the synthesized compounds were docked inside the active site of the COX-2 and LOX enzymes. They linked to COX-2 through the N atom of the azole scaffold, while CO of the oxazolone moiety was responsible for the binding to amino acids inside the LOX active site.

• MeSH
• antiflogistika nesteroidní chemická syntéza   chemie   farmakologie   MeSH
• arachidonát-5-lipoxygenasa metabolismus   MeSH
• cyklooxygenasa 2 metabolismus   MeSH
• imidazoly chemická syntéza   chemie   farmakologie   MeSH
• inhibitory cyklooxygenasy 2 chemická syntéza   chemie   farmakologie   MeSH
• inhibitory lipoxygenas chemická syntéza   chemie   farmakologie   MeSH
• kultivované buňky MeSH
• lidé MeSH
• molekulární struktura MeSH
• racionální návrh léčiv * MeSH
• simulace molekulového dockingu MeSH
• viabilita buněk účinky léků   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Geranyl flavones have been studied as compounds that potentially can be developed as anti-inflammatory agents. A series of natural geranylated flavanones was isolated from Paulownia tomentosa fruits, and these compounds were studied for their anti-inflammatory activity and possible mechanism of action. Two new compounds were characterized [paulownione C (17) and tomentodiplacone O (20)], and all of the isolated derivatives were assayed for their ability to inhibit cyclooxygenases (COX-1 and COX-2) and 5-lipoxygenase (5-LOX). The compounds tested showed variable degrees of activity, with several of them showing activity comparable to or greater than the standards used in COX-1, COX-2, and 5-LOX assays. However, only the compound tomentodiplacone O (20) showed more selectivity against COX-2 versus COX-1 when compared with ibuprofen. The ability of the test compounds to interact with the above-mentioned enzymes was supported by docking studies, which revealed the possible incorporation of selected test substances into the active sites of these enzymes. Furthermore, one of the COX/LOX dual inhibitors, diplacone (14) (a major geranylated flavanone of P. tomentosa), was studied in vitro to obtain a proteomic overview of its effect on inflammation in LPS-treated THP-1 macrophages, supporting its previously observed anti-inflammatory activity and revealing the mechanism of its anti-inflammatory effect.

• MeSH
• antiflogistika chemie   izolace a purifikace   farmakologie   MeSH
• arachidonát-5-lipoxygenasa metabolismus   MeSH
• cyklooxygenasa 1 metabolismus   MeSH
• cyklooxygenasa 2 metabolismus   MeSH
• flavonoidy chemie   izolace a purifikace   farmakologie   MeSH
• inhibitory cyklooxygenasy 2 chemie   izolace a purifikace   farmakologie   MeSH
• inhibitory lipoxygenas chemie   izolace a purifikace   farmakologie   MeSH
• Magnoliopsida chemie   MeSH
• molekulární struktura MeSH
• ovoce chemie   MeSH
• proteomika * MeSH
• Publikační typ
• časopisecké články MeSH

Two new series of N-substituted indole derivatives 4a-l and 5a-h were synthesized. Their chemical structures were confirmed using spectroscopic tools including IR, (1)H NMR, (13)C NMR mass spectroscopy and elemental analyses. The results showed no significant cytotoxic activity on either cancer or normal human cells. Anti-inflammatory activity for all target compounds was evaluated in vitro. Compounds 5a-h were found to have better anti-inflammatory activity than 4a-l. The inhibitory activity of COX-2 and 5-LOX were tested for 5a-h. Three compounds, 5c, 5d and 5f showed excellent COX-2 inhibitory activity with IC50 ranging from 0.98 to 1.23 μM compared to the reference celecoxib (1.54 μM). These compounds had a reasonable selectivity index between 7.03 and 8.05. Additionally, p-methylbenzoyl derivative 5g (IC50 = 5.78 μM) had superior 5-LOX inhibitory activity, higher than quercetin. 5e was close to quercetin in its LOX inhibitory activity. Compounds 5a-h were docked inside the active site of COX-2 and 5-LOX enzymes.

• MeSH
• antiflogistika chemická syntéza   chemie   metabolismus   farmakologie   MeSH
• arachidonát-5-lipoxygenasa chemie   metabolismus   MeSH
• cyklooxygenasa 1 metabolismus   MeSH
• cyklooxygenasa 2 metabolismus   MeSH
• indoly chemická syntéza   chemie   metabolismus   farmakologie   MeSH
• inhibitory cyklooxygenasy 2 chemická syntéza   chemie   metabolismus   farmakologie   MeSH
• inhibitory lipoxygenas chemická syntéza   chemie   metabolismus   farmakologie   MeSH
• katalytická doména MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• protinádorové látky chemická syntéza   chemie   metabolismus   farmakologie   MeSH
• racionální návrh léčiv * MeSH
• Schiffovy báze chemie   MeSH
• simulace molekulového dockingu * MeSH
• techniky syntetické chemie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

The induced differentiation of tumor cells into mature phenotypes is a promising strategy in cancer therapy. In this study, the effects of combined treatment with all-trans retinoic acid (ATRA) and lipoxygenase/cyclooxygenase inhibitors were examined in two osteosarcoma cell lines, Saos-2 and OSA-01. Caffeic acid and celecoxib were used as inhibitors of 5-lipoxygenase and of cyclooxygenase-2, respectively. Changes in the cell proliferation, matrix mineralization, and occurrence of differentiation markers were evaluated in treated cell populations at intervals. The results confirmed the capability of caffeic acid to enhance the antiproliferative effect of ATRA in both cell lines. In contrast, celecoxib showed the same effect in Saos-2 cells only. Furthermore, the extension of matrix mineralization was observed after combined treatment with ATRA and celecoxib or caffeic acid. The increased expression of osteogenic differentiation markers was observed in both cell lines after the combined application of ATRA and inhibitors. The obtained results clearly demonstrate the capability of lipoxygenase/cyclooxygenase inhibitors to enhance the antiproliferative and differentiating effect of ATRA in osteosarcoma cells, although some of these effects are specific and depend on the biological features of the respective tumor or cell line.

• MeSH
• buněčná diferenciace účinky léků   MeSH
• inhibitory cyklooxygenasy farmakologie   MeSH
• inhibitory lipoxygenas farmakologie   MeSH
• kyseliny kávové farmakologie   MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• nádory kostí farmakoterapie   patologie   MeSH
• osteosarkom farmakoterapie   patologie   MeSH
• proliferace buněk účinky léků   MeSH
• protinádorové látky farmakologie   MeSH
• pyrazoly farmakologie   MeSH
• sulfonamidy farmakologie   MeSH
• tretinoin farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Reactive oxygen species formed as a response to various abiotic and biotic stresses cause an oxidative damage of cellular component such are lipids, proteins and nucleic acids. Lipid peroxidation is considered as one of the major processes responsible for the oxidative damage of the polyunsaturated fatty acid in the cell membranes. Various methods such as a loss of polyunsaturated fatty acids, amount of the primary and the secondary products are used to monitor the level of lipid peroxidation. To investigate the use of ultra-weak photon emission as a non-invasive tool for monitoring of lipid peroxidation, the involvement of lipid peroxidation in ultra-weak photon emission was studied in the unicellular green alga Chlamydomonas reinhardtii. Lipid peroxidation initiated by addition of exogenous linoleic acid to the cells was monitored by ultra-weak photon emission measured with the employment of highly sensitive charged couple device camera and photomultiplier tube. It was found that the addition of linoleic acid to the cells significantly increased the ultra-weak photon emission that correlates with the accumulation of lipid peroxidation product as measured using thiobarbituric acid assay. Scavenging of hydroxyl radical by mannitol, inhibition of intrinsic lipoxygenase by catechol and removal of molecular oxygen considerably suppressed ultra-weak photon emission measured after the addition of linoleic acid. The photon emission dominated at the red region of the spectrum with emission maximum at 680 nm. These observations reveal that the oxidation of linoleic acid by hydroxyl radical and intrinsic lipoxygenase results in the ultra-weak photon emission. Electronically excited species such as excited triplet carbonyls are the likely candidates for the primary excited species formed during the lipid peroxidation, whereas chlorophylls are the final emitters of photons. We propose here that the ultra-weak photon emission can be used as a non-invasive tool for the detection of lipid peroxidation in the cell membranes.

• MeSH
• buněčná membrána účinky léků   metabolismus   MeSH
• Chlamydomonas reinhardtii cytologie   účinky léků   metabolismus   MeSH
• fotony MeSH
• histidin farmakologie   MeSH
• hydroxylový radikál metabolismus   MeSH
• inhibitory lipoxygenas farmakologie   MeSH
• kyselina linolová farmakologie   MeSH
• kyslík metabolismus   MeSH
• lipoxygenasa metabolismus   MeSH
• malondialdehyd metabolismus   MeSH
• mannitol farmakologie   MeSH
• peroxidace lipidů účinky léků   MeSH
• thiobarbituráty metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

We investigated the possible modulation by LOX/ COX inhibitors of all-trans retinoic acid (ATRA)-induced cell differentiation in two established neuroblastoma cell lines, SH-SY5Y and SK-N-BE(2). Caffeic acid, as an inhibitor of 5-lipoxygenase, and celecoxib, as an inhibitor of cyclooxygenase-2, were chosen for this study. The effects of the combined treatment with ATRA and LOX/COX inhibitors on neuroblastoma cells were studied using cell morphology assessment, detection of differentiation markers by immunoblotting, measurement of proliferation activity, and cell cycle analysis and apoptosis detection by flow cytometry. The results clearly demonstrated the potential of caffeic acid to enhance ATRA-induced cell differentiation, especially in the SK-N-BE(2) cell line, whereas application of celecoxib alone or with ATRA led predominantly to cytotoxic effects in both cell lines. Moreover, the higher sensitivity of the SK-N-BE(2) cell line to combined treatment with ATRA and LOX/COX inhibitors suggests that cancer stem cells are a main target for this therapeutic approach. Nevertheless, further detailed study of the phenomenon of enhanced cell differentiation by expression profiling is needed.

• MeSH
• apoptóza účinky léků   MeSH
• buněčná diferenciace účinky léků   MeSH
• buněčný cyklus účinky léků   MeSH
• inhibitory cyklooxygenasy 2 farmakologie   MeSH
• inhibitory lipoxygenas farmakologie   MeSH
• kyseliny kávové farmakologie   MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• neuroblastom farmakoterapie   enzymologie   patologie   MeSH
• průtoková cytometrie MeSH
• pyrazoly farmakologie   MeSH
• sulfonamidy farmakologie   MeSH
• tretinoin farmakologie   MeSH
• tvar buňky účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: We performed expression profiling of two neuroblastoma cell lines, SK-N-BE(2) and SH-SY5Y, after combined treatment with all-trans retinoic acid (ATRA) and inhibitors of lipoxygenases (LOX) and cyclooxygenases (COX). This study is a continuation of our previous work confirming the possibility of enhancing ATRA-induced cell differentiation in these cell lines by the application of LOX/COX inhibitors and brings more detailed information concerning the mechanisms of the enhancement of ATRA-induced differentiation of neuroblastoma cells. METHODS: Caffeic acid, as an inhibitor of 5-lipoxygenase, and celecoxib, as an inhibitor on cyclooxygenase-2, were used in this study. Expression profiling was performed using Human Cancer Oligo GEArray membranes that cover 440 cancer-related genes. RESULTS: Cluster analyses of the changes in gene expression showed the concentration-dependent increase in genes known to be involved in the process of retinoid-induced neuronal differentiation, especially in cytoskeleton remodeling. These changes were detected in both cell lines, and they were independent of the type of specific inhibitors, suggesting a common mechanism of ATRA-induced differentiation enhancement. Furthermore, we also found overexpression of some genes in the same cell line (SK-N-BE(2) or SH-SY5Y) after combined treatment with both ATRA and CA, or ATRA and CX. Finally, we also detected that gene expression was changed after treatment with the same inhibitor (CA or CX) in combination with ATRA in both cell lines. CONCLUSIONS: Obtained results confirmed our initial hypothesis of the common mechanism of enhancement in ATRA-induced cell differentiation via inhibition of arachidonic acid metabolic pathway.

• MeSH
• buněčná diferenciace účinky léků   MeSH
• inhibitory cyklooxygenasy farmakologie   MeSH
• inhibitory enzymů farmakologie   MeSH
• inhibitory lipoxygenas farmakologie   MeSH
• kyseliny kávové farmakologie   MeSH
• lidé MeSH
• multigenová rodina MeSH
• nádory mozku farmakoterapie   patologie   MeSH
• neuroblastom farmakoterapie   patologie   MeSH
• oxidační stres MeSH
• pyrazoly farmakologie   MeSH
• regulace genové exprese u nádorů MeSH
• stanovení celkové genové exprese MeSH
• sulfonamidy farmakologie   MeSH
• tretinoin metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The block of hematopoietic differentiation program in acute myeloid leukemia cells can be overcome by differentiating agent like retinoic acid, but it has several side effects. A study of other differentiation signaling pathways is therefore useful to predict potential targets of anti-leukemic therapy. We demonstrated previously that the co-treatment of HL-60 cells with Tumor necrosis factor-alpha (TNF-alpha) (1 ng/mL) and inhibitor of 5-lipoxygenase MK886 (5 microm) potentiated both monocytic differentiation and apoptosis. In this study, we detected enhanced activation of three main types of mitogen-activated protein kinases (MAPKs) (p38, c-Jun amino-terminal kinase [JNK], extracellular signal-regulated kinase [ERK]), so we assessed their role in differentiation using appropriate pharmacologic inhibitors. The inhibition of pro-apoptotic MAPKs (p38 and JNK) suppressed the effect of MK886 + TNF-alpha co-treatment. On the other hand, down-regulation of pro-survival ERK pathway led to increased differentiation. Those effects were accompanied by increased activation of caspases in cells treated by MK886 + TNF-alpha. Pan-caspase inhibitor ZVAD-fmk significantly decreased both number of apoptotic and differentiated cells. The same effect was observed after inhibition of caspase 9, but not caspase 3 and 8. To conclude, we evidenced that the activation of apoptotic processes and pathways supporting apoptosis (p38 and JNK MAPKs) is required for the monocytic differentiation of HL-60 cells.

• MeSH
• aktivace enzymů účinky léků   MeSH
• akutní promyelocytární leukemie farmakoterapie   metabolismus   patologie   MeSH
• apoptóza fyziologie   účinky léků   MeSH
• buněčná diferenciace účinky léků   MeSH
• chloromethylketony aminokyselin farmakologie   MeSH
• HL-60 buňky MeSH
• indoly farmakologie   MeSH
• inhibitory cysteinových proteinas farmakologie   MeSH
• inhibitory kaspas MeSH
• inhibitory lipoxygenas farmakologie   MeSH
• kaspasy metabolismus   MeSH
• lidé MeSH
• MAP kinasový signální systém účinky léků   MeSH
• monocyty patologie   účinky léků   MeSH
• NF-kappa B antagonisté a inhibitory   MeSH
• TNF-alfa farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH