Microbial adhesion to surfaces and the subsequent biofilm formation may result in contamination in food industry and in healthcare-associated infections and may significantly affect postoperative care. Some plants produce substances with antioxidant and antimicrobial properties that are able to inhibit the growth of food-borne pathogens. The aim of our study was to evaluate antimicrobial and anti-biofilm effect of baicalein, resveratrol, and pterostilbene on Candida albicans, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Escherichia coli. We determined the minimum inhibitory concentrations (MIC), the minimum adhesion inhibitory concentration (MAIC), and the minimum biofilm eradication concentration (MBEC) by crystal violet and XTT determination. Resveratrol and pterostilbene have been shown to inhibit the formation of biofilms as well as to disrupt preformed biofilms. Our results suggest that resveratrol and pterostilbene appear potentially very useful to control and inhibit biofilm contaminations by Candida albicans, Staphylococcus epidermidis, and Escherichia coli in the food industry.

• Klíčová slova
• Adhesion, Baicalein, Biofilm, Eradication, Pterostilbene, Resveratrol,
• MeSH
• antiinfekční látky farmakologie   MeSH
• biofilmy účinky léků   růst a vývoj   MeSH
• Candida albicans účinky léků   růst a vývoj   MeSH
• Escherichia coli účinky léků   růst a vývoj   MeSH
• flavanony farmakologie   MeSH
• mikrobiální testy citlivosti MeSH
• Pseudomonas aeruginosa účinky léků   růst a vývoj   MeSH
• resveratrol MeSH
• rostlinné extrakty chemie   farmakologie   MeSH
• Staphylococcus epidermidis účinky léků   růst a vývoj   MeSH
• stilbeny farmakologie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antiinfekční látky MeSH
• baicalein MeSH Prohlížeč
• flavanony MeSH
• pterostilbene MeSH Prohlížeč
• resveratrol MeSH
• rostlinné extrakty MeSH
• stilbeny MeSH

Heat stress (HS) in poultry husbandry is an important stressor and with increasing global temperatures its importance will increase. The negative effects of stress on the quality and quantity of poultry production are described in a range of research studies. However, a lack of attention is devoted to the impacts of HS on individual chicken immune cells and whole lymphoid tissue in birds. Oxidative stress and increased inflammation are accompanying processes of HS, but with deleterious effects on the whole organism. They play a key role in the inflammation and oxidative stress of the chicken immune system. There are a range of strategies that can help mitigate the adverse effects of HS in poultry. Phytochemicals are well studied and some of them report promising results to mitigate oxidative stress and inflammation, a major consequence of HS. Current studies revealed that mitigating these two main impacts of HS will be a key factor in solving the problem of increasing temperatures in poultry production. Improved function of the chicken immune system is another benefit of using phytochemicals in poultry due to the importance of poultry health management in today's post pandemic world. Based on the current literature, baicalin and baicalein have proven to have strong anti-inflammatory and antioxidative effects in mammalian and avian models. Taken together, this review is dedicated to collecting the literature about the known effects of HS on chicken immune cells and lymphoid tissue. The second part of the review is dedicated to the potential use of baicalin and baicalein in poultry to mitigate the negative impacts of HS on poultry production.

• Klíčová slova
• baicalein, baicalin, broiler chicken, heat stress, immune system,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

The antioxidant properties of flavonoids are mediated by their functional hydroxyl groups, which are capable of both chelating redox active metals such as iron, copper and scavenging free radicals. In this paper, the antioxidant vs. prooxidant and DNA protecting properties of baicalein and Cu(II)-baicalein complexes were studied under the conditions of the Copper-Fenton reaction and of the Copper-Ascorbate system. From the relevant EPR spectra, the interaction of baicalein with Cu(II) ions was confirmed, while UV-vis spectroscopy demonstrated a greater stability over time of Cu(II)-baicalein complexes in DMSO than in methanol and PBS and Phosphate buffers. An ABTS study confirmed a moderate ROS scavenging efficiency, at around 37%, for both free baicalein and Cu(II)-baicalein complexes (in the ratios 1:1 and 1:2). The results from absorption titrations are in agreement with those from viscometric studies and confirmed that the binding mode between DNA and both free baicalein and Cu-baicalein complexes, involves hydrogen bonds and van der Waals interactions. The DNA protective effect of baicalein has been investigated by means of gel electrophoresis under the conditions of the Cu-catalyzed Fenton reaction and of the Cu-Ascorbate system. In both cases, it was found that, at sufficiently high concentrations, baicalein offers some protection to cells from DNA damage caused by ROS (singlet oxygen, hydroxyl radicals and superoxide radical anions). Accordingly, baicalein may be useful as a therapeutic agent in diseases with a disturbed metabolism of redox metals such as copper, for example Alzheimer's disease, Wilson's disease and various cancers. While therapeutically sufficient concentrations of baicalein may protect neuronal cells from Cu-Fenton-induced DNA damage in regard to neurological conditions, conversely, in the case of cancers, low concentrations of baicalein do not inhibit the pro-oxidant effect of copper ions and ascorbate, which can, in turn, deliver an effective damage to DNA in tumour cells.

• Klíčová slova
• Antioxidant, Baicalein, Copper(II), DNA damage, Gel electrophoresis, Prooxidant, Radical scavenging, Spectroscopy,
• MeSH
• antioxidancia * chemie   MeSH
• DNA metabolismus   MeSH
• flavonoidy MeSH
• hydroxylový radikál metabolismus   MeSH
• kovy MeSH
• kyselina askorbová MeSH
• měď * chemie   MeSH
• oxidace-redukce MeSH
• poškození DNA MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antioxidancia * MeSH
• baicalein MeSH Prohlížeč
• DNA MeSH
• flavonoidy MeSH
• hydroxylový radikál MeSH
• kovy MeSH
• kyselina askorbová MeSH
• měď * MeSH
• reaktivní formy kyslíku MeSH

Biofilms are often the cause of chronic human infections and contaminate industrial or medical equipment. The traditional approach has been to use increasing concentrations of antibiotics, but microorganisms rapidly develop multiresistance to them. Therefore, we investigated the use of natural substances as an alternative solution. The quantification of the biofilms based on the colonized areas was measured using a Cellavista automatic microscope equipped with image analysis software. Using the Cellavista device brings new possibilities for qualification and quantification of sessile cells. In our study, this feature was documented by exploring the antifungal/anti-biofilm activity of amphotericin B, baicalein, chitosan and usnic acid against yeast biofilm formation. The influence of these substances on the formation and eradication of opportunistic pathogenic yeasts Candida parapsilosis and Candida krusei biofilms was studied in 96-well polystyrene microtiter plates. While amphotericin B was not very efficient, the use of baicalein and chitosan, even in minimum inhibitory concentrations, was found to rapidly decrease the colonized areas in the wells. The usnic acid did not display any significant antibiofilm properties even at concentration 300μgml(-1). Our results propose that Cellavista is a promising tool for the study of yeast biofilm formation and the effects of antimicrobial agents.

• Klíčová slova
• Baicalein, Biofilm, Candida krusei, Candida parapsilosis, Cellavista, Chitosan, Eradication, Inhibition,
• MeSH
• amfotericin B farmakologie   MeSH
• antiinfekční látky farmakologie   MeSH
• benzofurany farmakologie   MeSH
• biofilmy účinky léků   MeSH
• Candida účinky léků   fyziologie   MeSH
• chitosan farmakologie   MeSH
• flavanony farmakologie   MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• mikroskopie metody   MeSH
• počítačové zpracování obrazu MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• amfotericin B MeSH
• antiinfekční látky MeSH
• baicalein MeSH Prohlížeč
• benzofurany MeSH
• chitosan MeSH
• flavanony MeSH
• usnic acid MeSH Prohlížeč

The biofilms of filamentous-forming fungi are a novel and still insufficiently understood research topic. We have studied Aspergillus fumigatus, an ubiquitous opportunistic pathogenic fungus, as a representative model for a study of biofilm formation by filamentous fungi and for assessing the potential anti-biofilm activity of natural substances. The activity of antibiotic amphotericin B and selected natural substances: baicalein, chitosan and rhamnolipid was studied. The minimum suspension inhibitory concentrations (MIC) were determined and the biofilm susceptibility was investigated by determining the metabolic activity of sessile cells (XTT assay) and total biofilm biomass (crystal violet staining). Significant time-dependent differences in substances' anti-biofilm activity were observed. Images of A. fumigatus biofilm were obtained by Cellavista automatic light microscope and spinning disc confocal microscopy. Baicalein and rhamnolipid were not found as suitable substances for inhibition of the A. fumigatus biofilm formation, as neither of the substances inhibited the sessile cells metabolic activity or the total biofilm biomass even at tenfold MIC after 48 h. In contrast, chitosan at 10 × MIC (25 µg mL-1), suppressed the biofilm metabolic activity by 90 % and the total biofilm biomass by 80 % even after 72 h of cultivation. Amphotericin B inhibited only 14 % of total biofilm biomass (crystal violet staining) and 35 % of metabolic activity (XTT assay) of adherent cells under the same conditions. Our results therefore suggest chitosan as potential alternative for treating A. fumigatus biofilm-associated infections.

• Klíčová slova
• Amphotericin B, Aspergillus fumigatus, Biofilm, Chitosan, Rhamnolipid,
• MeSH
• amfotericin B farmakologie   MeSH
• antifungální látky farmakologie   MeSH
• Aspergillus fumigatus účinky léků   fyziologie   MeSH
• biofilmy účinky léků   MeSH
• chitosan farmakologie   MeSH
• flavanony farmakologie   MeSH
• glykolipidy farmakologie   MeSH
• mikrobiální testy citlivosti MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• amfotericin B MeSH
• antifungální látky MeSH
• baicalein MeSH Prohlížeč
• chitosan MeSH
• flavanony MeSH
• glykolipidy MeSH
• rhamnolipid MeSH Prohlížeč

The constitutive androstane receptor (CAR) is a crucial transcriptional regulator of key xenobiotic-metabolizing enzymes such as cytochrome P450 CYP3A4, CYP2C9 and CYP2B6. The flavonoids chrysin, baicalein and galangin have been reported to activate CAR and interfere with EGFR signaling. Nevertheless, it is not known if these flavonoids are direct CAR ligands or indirect phenobarbital-like CAR activators via the inhibition of epidermal growth factor receptor (EGFR) signaling. We analyze the interactions of chrysin, galangin and baicalein and its glycoside baicalin with human CAR. We have employed and validated methods that can study direct interaction with the CAR ligand binding pocket. Secondly, we determined if the compounds affect human EGFR signaling and interact with EGFR. Employing a TR-FRET coactivator assay with recombinant CAR or CAR assembly assay, a consistent activation of CAR with flavonoids and phenobarbital was not observed. It was determined, however, that galangin, chrysin, and baicalein may slightly repress EGFR-Tyr1068 autophosphorylation after EGF treatment, phosphorylation of downstream transcription factor ELK1 and stimulate EGFP-CAR nuclear translocation in primary human hepatocytes. These data suggest that flavonoids chrysin, galangin and baicalein are indirect human CAR activators. This study also demonstrates new approach how to test the direct CAR interaction with its ligands.

• Klíčová slova
• Constitutive androstane receptor, Cytochrome P450, Flavonoids, Gene regulation, Nuclear receptors,
• MeSH
• buněčné linie MeSH
• cytochrom P450 CYP2B6 metabolismus   MeSH
• erbB receptory účinky léků   MeSH
• fenobarbital farmakologie   MeSH
• flavanony farmakologie   MeSH
• flavonoidy farmakologie   MeSH
• hepatocyty účinky léků   metabolismus   MeSH
• konstitutivní androstanový receptor MeSH
• lidé MeSH
• protein Elk-1 s doménou ets účinky léků   genetika   MeSH
• receptory cytoplazmatické a nukleární agonisté   MeSH
• transport proteinů účinky léků   MeSH
• vazebná místa účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• baicalein MeSH Prohlížeč
• chrysin MeSH Prohlížeč
• cytochrom P450 CYP2B6 MeSH
• ELK1 protein, human MeSH Prohlížeč
• erbB receptory MeSH
• fenobarbital MeSH
• flavanony MeSH
• flavonoidy MeSH
• galangin MeSH Prohlížeč
• konstitutivní androstanový receptor MeSH
• protein Elk-1 s doménou ets MeSH
• receptory cytoplazmatické a nukleární MeSH

Cobalt intoxication can occur after its release from metal-based prostheses, which is generally clinically severe. Therefore, there is a need for the development of a cobalt chelator since there are currently no approved drugs for cobalt intoxication. As flavonoids are known for their metal chelating properties and safety, the screening of cobalt chelating properties was performed in a total of 23 flavonoids by our recently developed new spectrophotometric assay. Further assessment of positive or negative consequences of cobalt chelation was performed both in vitro and ex vivo. Six and thirteen flavonoids significantly chelated cobalt ions at pH 7.5 and 6.8, respectively. Baicalein demonstrated a significant activity even at pH 5.5; however, none of the flavonoids showed chelation at pH 4.5. In general, baicalein and 3-hydroxyflavone were the most active. They also mildly decreased the cobalt-triggered Fenton reaction, but baicalein toxicity toward red blood cells was strongly increased by the addition of cobalt. Quercetin, tested as an example of flavonoid unable to chelate cobalt ions significantly, stimulated both the cobalt-based Fenton reaction and the lysis of erythrocytes in the presence of cobalt. Therefore, 3-hydroxyflavone can serve as a potential template for the development of novel cobalt chelators.

• Publikační typ
• časopisecké články MeSH

Flavonoids are found universally in plants and act as free radical scavenging and chelating agents with antiinflammatory, antiischemic, vasodilating and chemoprotective properties. In this study, the antilipoperoxidative and cytoprotective effects of apigenin, baicalein, kaempferol, luteolin and quercetin against doxorubicin-induced oxidative stress were investigated in isolated rat heart cardiac myocytes, mitochondria and microsomes. After preincubation of cardiomyocytes with the test compounds for 1 h the cardiomyocytes were treated with the toxic agent, doxorubicin (100 micro M for 8 h). Cardiomyocyte protection was assessed by extracellular LDH and cellular ADP and ATP production. Cytoprotection was concentration dependent for baicalein > luteolin congruent with apigenin > quercetin > kaempferol. All test compounds had signi fi cantly better protective effects than dexrazoxan, an agent currently used for adjuvant therapy during anthracycline antibiotic therapy. In microsomes/mitochondria the IC(50) values of lipid peroxidation inhibition for quercetin, baicalein, kaempferol, luteolin, and apigenin were 3.1 +/- 0.2/8.2 +/- 0.6, 3.3 +/- 0.3/9.6 +/- 0.5, 3.9 +/- 0.3/10.1 +/- 0.8, 22.9 +/- 1.7/18.2 +/- 0.7, and 338.8 +/- 23.1/73.1 +/- 6.4 mM, respectively. The antilipoperoxidative activity of apigenin differed from its cytoprotective effects, but correlated with the free radical scavenging of 2,2-diphenyl-1-picrylhydrazyl radical and half peak oxidation potential (E(p/2)). Apigenin was the least effective of the flavonoids studied in all models except the cardiomyocyte model where its cardiomyocyte cytoprotective effect was comparable to other compounds.

• MeSH
• apigenin MeSH
• bifenylové sloučeniny MeSH
• flavanony * MeSH
• flavonoidy farmakologie   MeSH
• fytoterapie * MeSH
• kardiomyocyty účinky léků   MeSH
• kempferoly farmakologie   MeSH
• krysa rodu Rattus MeSH
• léčivé rostliny * MeSH
• luteolin MeSH
• mikrozomy účinky léků   MeSH
• ochranné látky farmakologie   MeSH
• peroxidace lipidů účinky léků   MeSH
• pikráty chemie   MeSH
• potkani Wistar MeSH
• quercetin farmakologie   MeSH
• scavengery volných radikálů farmakologie   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 1,1-diphenyl-2-picrylhydrazyl MeSH Prohlížeč
• apigenin MeSH
• baicalein MeSH Prohlížeč
• bifenylové sloučeniny MeSH
• flavanony * MeSH
• flavonoidy MeSH
• kaempferol MeSH Prohlížeč
• kempferoly MeSH
• luteolin MeSH
• ochranné látky MeSH
• pikráty MeSH
• quercetin MeSH
• scavengery volných radikálů MeSH

This work focused on the cultivation of S. baicalensis Georgii in vitro cultures and on the possibilities of increasing the production of secondary metabolites in these cultures. The aim of the Sstudy was to determine whether the baicalin transport through vacuolar membrane is dependent on the presence of Mg-ATP. Our results showed that Mg-ATP had a significant effect on the ratio of baicalin and baicalein content and on the transport speed of these flavonoids. Therefore, the transport mechanism for baicalin are probably some of the MRP proteins which are the subfamily of the ABC transporte

• MeSH
• adenosintrifosfát farmakologie   MeSH
• flavanony biosyntéza   MeSH
• flavonoidy biosyntéza   MeSH
• kořeny rostlin MeSH
• kultivované buňky MeSH
• methylenová modř farmakologie   MeSH
• peroxid vodíku farmakologie   MeSH
• šišák bajkalský metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adenosintrifosfát MeSH
• baicalein MeSH Prohlížeč
• baicalin MeSH Prohlížeč
• flavanony MeSH
• flavonoidy MeSH
• methylenová modř MeSH
• peroxid vodíku MeSH

The level of differentiation could influence sensitivity of colonic epithelial cells to various stimuli. In our study, the effects of TNF-alpha, inhibitors of arachidonic acid (AA) metabolism (baicalein, BA; indomethacin, INDO; niflumic acid, NA; nordihydroguaiaretic acid, NDGA), and/or their combinations on undifferentiated or sodium butyrate (NaBt)-differentiated human colon adenocarcinoma HT-29 cells were compared. NaBt-treated cells became growth arrested (blocked in G0/G1 phase of the cell cycle), and showed down-regulated Bcl-xL and up-regulated Bak proteins and increased expression of cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX). These cells were more perceptive to anti-proliferative and apoptotic effects of TNF-alpha. Both inhibitors of LOX (BA and NDGA) and COX (INDO and NA) in higher concentrations modulated cell cycle changes accompanying NaBt-induced differentiation and induced various level of cell death in undifferentiated and differentiated cells. Most important is our finding that TNF-alpha action on proliferation and cell death can be potentiated by co-treatment of cells with AA metabolism inhibitors, and that these effects were more significant in undifferentiated cells. TNF-alpha and INDO co-treatment was associated with accumulation of cells in G0/G1 cell cycle phase, increased reactive oxygen species production, and elevated caspase-3 activity. These results indicate the role of differentiation status in the sensitivity of HT-29 cells to the anti-proliferative and proapoptotic effects of TNF-alpha, AA metabolism inhibitors, and their combinations, and imply promising possibility for novel anti-cancer strategies.

• MeSH
• adenokarcinom farmakoterapie   patologie   MeSH
• arachidonát-5-lipoxygenasa metabolismus   MeSH
• buněčná diferenciace účinky léků   MeSH
• buněčné dělení účinky léků   MeSH
• buněčný cyklus účinky léků   MeSH
• buňky HT-29 účinky léků   MeSH
• butyráty farmakologie   MeSH
• cyklooxygenasa 2 MeSH
• cyklooxygenasy metabolismus   MeSH
• flavanony * MeSH
• flavonoidy farmakologie   MeSH
• indomethacin farmakologie   MeSH
• inhibitory cyklooxygenasy 2 MeSH
• inhibitory cyklooxygenasy farmakologie   MeSH
• inhibitory lipoxygenas farmakologie   MeSH
• izoenzymy antagonisté a inhibitory   metabolismus   MeSH
• kaspasa 3 MeSH
• kaspasy účinky léků   metabolismus   MeSH
• kyselina arachidonová metabolismus   MeSH
• kyselina niflumová farmakologie   MeSH
• kyselina nordihydroguaiaretová farmakologie   MeSH
• lidé MeSH
• membránové proteiny MeSH
• nádory tračníku farmakoterapie   metabolismus   patologie   MeSH
• synergismus léků MeSH
• TNF-alfa farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• arachidonát-5-lipoxygenasa MeSH
• baicalein MeSH Prohlížeč
• butyráty MeSH
• CASP3 protein, human MeSH Prohlížeč
• cyklooxygenasa 2 MeSH
• cyklooxygenasy MeSH
• flavanony * MeSH
• flavonoidy MeSH
• indomethacin MeSH
• inhibitory cyklooxygenasy 2 MeSH
• inhibitory cyklooxygenasy MeSH
• inhibitory lipoxygenas MeSH
• izoenzymy MeSH
• kaspasa 3 MeSH
• kaspasy MeSH
• kyselina arachidonová MeSH
• kyselina niflumová MeSH
• kyselina nordihydroguaiaretová MeSH
• membránové proteiny MeSH
• PTGS2 protein, human MeSH Prohlížeč
• TNF-alfa MeSH