RESUMEN
OBJECTIVES: The Slovak Medical University (SMU) holds a unique position in the health education system in Slovakia. It has a direct connection to the health sector, allowing health education to reflect the actual needs in this field. Because of increasing importance of public health in the last decades, more attention must be given to disease prevention and the promotion of healthy lifestyles. We aim to highlight the main characteristics of health higher education at one of the specialized health universities in Slovakia, with a particular focus on public health and its practical impacts. METHODS: We analysed the available legal regulations for postgraduate studies in Slovakia and the officially valid documents of the Faculty of Public Health (FPH) and the Slovak Medical University in accordance with the accredited study programme in Public Health. Archived data from the Department of Science, Research, and Doctoral Studies of the Faculty over the past 10 years were used for the analysis of postgraduate studies (2013-2023). RESULTS: PhD studies in Slovakia are conducted in accordance with Act No. 131/2002 Coll. on Higher Education Institutions and on amendments to certain acts. There are two forms of PhD study in Slovakia: full-time and external. The evaluation of study results is based on the credit system. The doctoral study programme proceeds according to an individual study plan under the guidance of the advisor. The PhD study concludes with the defence of the dissertation, which serves as the final thesis. A total of 97 students have graduated at FPH SMU in Public Health in the last 10 years. The majority of graduates were females (68% vs. 32% males) and studied in the external form of study (80.4% vs. 19.6% in the full-time programme). The most frequent research topics at FPH SMU in the last 10 years included Epidemiology and Prevention of Non-communicable (21.7%) and Infectious Diseases (11.3%), Health Management and Policy (17.5%), Environmental Health (15.5%), as well as Occupational Health (13.4%). CONCLUSION: High-quality and innovative postgraduate education in public health plays a crucial role in this field, preparing experts for the public health services. From a quality perspective, it is substantial to share experiences with various study programmes across the European region, as well as with other universities. Graduates of the Faculty of Public Health are highly sought-after professionals with diverse career opportunities not only in Slovakia but also within the European Union, other countries, and various important international institutions.
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Educación de Postgrado , Salud Pública , Eslovaquia , Humanos , Femenino , Masculino , Docentes Médicos , Escuelas de Salud Pública/organización & administración , UniversidadesRESUMEN
Secondary metabolites as a potential source of anticancer therapeutics have been the subject of many studies. Since hypericin, a metabolite isolated from Hypericum perforatum L., shows several biomedical properties applicable in oncology, the aim of our study was to investigate its potential precursor skyrin in terms of genotoxic and DNA-protective effects. These skyrin effects were analyzed by cell-free methods, and cytotoxicity was estimated by an MTT assay and by a trypan blue exclusion test, while the genotoxic/antigenotoxic potential was examined by comet assay using non-cancerous human lymphocytes and the HepG2 cancer cell line. Skyrin did not show DNA-damaging effects but rather exhibited DNA-protectivity using a DNA-topology assay. However, we observed only weak antioxidant and chelating skyrin properties in other cell-free methods. Regarding the cytotoxic activity of skyrin, HepG2 cells were more prone to skyrin-induced death in comparison to human lymphocytes. Skyrin in non-cytotoxic concentrations did not exhibit elevated genotoxicity in both cell types. On the other hand, skyrin displayed moderate DNA-protective effects that were more noticeable in the case of non-cancerous human lymphocytes. The potential genotoxic effects of skyrin were not observed, and its DNA-protective capacity was more prominent in non-cancerous cells. Therefore, skyrin might be a promising agent used in anticancer therapy.
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Antineoplásicos , Daño del ADN , Antraquinonas , ADN , HumanosRESUMEN
Intensive investigation for novel antiproliferative and cytotoxic effective chemical compounds is currently concentrated on structurally modified agents of natural or synthetic source. The selenium derivative of triorganotin compound, triphenyltin isoselenocyanate (TPT-NCSe) caused higher cytotoxicity in hormone sensitive MCF 7 (IC 50-250 nM) in comparison with triple-negative MDA-MB-231 breast carcinoma cell line (IC 50-450 nM) as determined by MTT assay. Measurement of DNA damage showed presence of crosslinks in both cell lines treated by increasing TPT-NCSe concentrations. This compound decreased mitochondrial membrane potential shown by JC-1 staining in a concentration-dependent manner in both cell lines. Activation of caspases-3/7 was observed in MDA-MB-231 cells and was significant only by concentrations causing significant level of crosslinks. On the other hand, migration assay revealed inhibitory effect of viability keeping 100 nM concentration of TPT-NCSe on migration of MDA-MB-231 cells. Our data has shown that this selenium containing triorganotin molecule exerts DNA damage-linked antineoplastic activity in breast carcinoma cell lines studied.
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Antineoplásicos , Neoplasias de la Mama , Selenio , Neoplasias de la Mama Triple Negativas , Antineoplásicos/química , Antineoplásicos/farmacología , Apoptosis , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular , Femenino , Humanos , Células MCF-7 , Compuestos de Organoselenio , Compuestos Orgánicos de Estaño , Selenio/farmacología , Neoplasias de la Mama Triple Negativas/metabolismoRESUMEN
Tyrosol (T) and hydroxytyrosol (HOT) and their glycosides are promising candidates for applications in functional food products or in complementary therapy. A series of phenylethanoid glycofuranosides (PEGFs) were synthesized to compare some of their biochemical and biological activities with T and HOT. The optimization of glycosylation promoted by environmentally benign basic zinc carbonate was performed to prepare HOT α-L-arabino-, ß-D-apio-, and ß-D-ribofuranosides. T and HOT ß-D-fructofuranosides, prepared by enzymatic transfructosylation of T and HOT, were also included in the comparative study. The antioxidant capacity and DNA-protective potential of T, HOT, and PEGFs on plasmid DNA were determined using cell-free assays. The DNA-damaging potential of the studied compounds for human hepatoma HepG2 cells and their DNA-protective potential on HepG2 cells against hydrogen peroxide were evaluated using the comet assay. Experiments revealed a spectrum of different activities of the studied compounds. HOT and HOT ß-D-fructofuranoside appear to be the best-performing scavengers and protectants of plasmid DNA and HepG2 cells. T and T ß-D-fructofuranoside display almost zero or low scavenging/antioxidant activity and protective effects on plasmid DNA or HepG2 cells. The results imply that especially HOT ß-D-fructofuranoside and ß-D-apiofuranoside could be considered as prospective molecules for the subsequent design of supplements with potential in food and health protection.
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Depuradores de Radicales Libres , Alcohol Feniletílico/análogos & derivados , Sistema Libre de Células/química , Sistema Libre de Células/metabolismo , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , Células Hep G2 , Humanos , Alcohol Feniletílico/química , Alcohol Feniletílico/farmacologíaRESUMEN
DNA double strand breaks (DSB) induced by ionizing radiation (IR) are usually measured using γH2AX/53BP1 DNA repair foci, that is considered to be the most sensitive assay for DSB analysis. While fluorescence microscopy (FM) is the gold standard for this analysis, imaging flow cytometry (IFC) may offer number of advantages such as lack of the fluorescence background, higher number of cells analyzed, and higher sensitivity in detection of DNA damage induced by IR at low doses. Along with appearance of γH2AX foci, the variable fraction of the cells exhibits homogeneously stained γH2AX signal resulting in so-called γH2AX pan-staining, which is believed to appear at early stages of apoptosis. Here, we investigated incidence of γH2AX pan-staining at different time points after irradiation with γ-rays using IFC and compared the obtained data with the data from FM. Appearance of γH2AX pan-staining during the apoptotic process was further analyzed by fluorescence-activated cell sorting (FACS) of cells at different stages of apoptosis and subsequent immunofluorescence analysis. Our results show that IFC was able to reveal dose dependence of pan-staining, while FM failed to detect all pan-staining cells. Moreover, we found that γH2AX pan-staining could be induced by therapeutic, but not low doses of γ-rays and correlate well with percentage of apoptotic cells was analyzed using flow cytometric Annexin-V/7-AAD assay. Further investigations showed that γH2AX pan-staining is formed in the early phases of apoptosis and remains until later stages of apoptotic process. Apoptotic DNA fragmentation as detected with comet assay using FM correlated with the percentage of live and late apoptotic/necrotic cells as analyzed by flow cytometry. Lastly, we successfully tested IFC for detection of γH2AX pan-staining and γH2AX/53BP1 DNA repair foci in lymphocyte of breast cancer patients after radiotherapy, which may be useful for assessing individual radiosensitivity in a clinically relevant cohort of patients.
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Histonas , Neoplasias , Reparación del ADN , Sangre Fetal/metabolismo , Citometría de Flujo , Histonas/metabolismo , Humanos , Linfocitos/metabolismo , Microscopía Fluorescente , Neoplasias/radioterapiaRESUMEN
Since the earliest agricultural attempts, humankind has been trying to improve crop quality and yields, as well as protect them from adverse conditions. Strategies to meet these goals include breeding, the use of fertilisers, and the genetic manipulation of crops, but also an interesting phenomenon called priming or adaptive response. Priming is based on an application of mild stress to prime a plant for another, mostly stronger stress. There are many priming techniques, such as osmopriming, halopriming, or using physical agents. Non-thermal plasma (NTP) represents a physical agent that contains a mixture of charged, neutral, and radical (mostly reactive oxygen and nitrogen species) particles, and can cause oxidative stress or even the death of cells or organisms upon interaction. However, under certain conditions, NTP can have the opposite effect, which has been previously documented for many plant species. Seed surface sterilization and growth enhancement are the most-reported positive effects of NTP on plants. Moreover, some studies suggest the role of NTP as a promising priming agent. This review deals with the effects of NTP treatment on plants from interaction with seed and cell surface, influence on cellular molecular processes, up to the adaptive response caused by NTP.
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Adaptación Biológica/efectos de los fármacos , Productos Agrícolas/efectos de los fármacos , Germinación/efectos de los fármacos , Gases em Plasma/farmacología , Estrés Fisiológico/efectos de los fármacos , Adaptación Biológica/genética , Productos Agrícolas/genética , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/efectos de la radiación , Germinación/genética , Estrés Oxidativo , Gases em Plasma/efectos adversos , Gases em Plasma/química , Especies de Nitrógeno Reactivo/metabolismo , Especies de Nitrógeno Reactivo/farmacología , Especies Reactivas de Oxígeno/metabolismo , Especies Reactivas de Oxígeno/farmacología , Semillas , Estrés Fisiológico/genéticaRESUMEN
There is clear evidence that ionizing radiation (IR) causes leukemia. For many types of leukemia, the preleukemic fusion genes (PFG), as consequences of DNA damage and chromosomal translocations, occur in hematopoietic stem and progenitor cells (HSPC) in utero and could be detected in umbilical cord blood (UCB) of newborns. However, relatively limited information is available about radiation-induced apoptosis, DNA damage and PFG formation in human HSPC. In this study we revealed that CD34+ HSPC compared to lymphocytes: (i) are extremely radio-resistant showing delayed time kinetics of apoptosis, (ii) accumulate lower level of endogenous DNA damage/early apoptotic γH2AX pan-stained cells, (iii) have higher level of radiation-induced 53BP1 and γH2AX/53BP1 co-localized DNA double stranded breaks, and (iv) after low dose of IR may form very low level of BCR-ABL PFG. Within CD34+ HSPC we identified CD34+CD38+ progenitor cells as a highly apoptosis-resistant population, while CD34+CD38- hematopoietic stem/multipotent progenitor cells (HSC/MPP) as a population very sensitive to radiation-induced apoptosis. Our study provides critical insights into how human HSPC respond to IR in the context of DNA damage, apoptosis and PFG.
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Roturas del ADN de Doble Cadena/efectos de la radiación , Sangre Fetal/efectos de la radiación , Fusión Génica/efectos de la radiación , Células Madre Hematopoyéticas/efectos de la radiación , Leucemia/genética , Antígenos CD34/metabolismo , Apoptosis/efectos de la radiación , Reparación del ADN/genética , Proteínas de Fusión bcr-abl/genética , Proteínas de Fusión bcr-abl/efectos de la radiación , Fusión Génica/genética , Histonas/genética , Histonas/metabolismo , Humanos , Recién Nacido , Linfocitos/efectos de la radiación , Preleucemia/genética , Radiación Ionizante , Proteína 1 de Unión al Supresor Tumoral P53/genética , Proteína 1 de Unión al Supresor Tumoral P53/metabolismoRESUMEN
Exposure to electromagnetic fields (EMF) has been associated with the increased risk of childhood leukemia, which arises from mutations induced within hematopoietic stem cells often through preleukemic fusion genes (PFG). In this study we investigated whether exposure to microwaves (MW) emitted by mobile phones could induce various biochemical markers of cellular damage including reactive oxygen species (ROS), DNA single and double strand breaks, PFG, and apoptosis in umbilical cord blood (UCB) cells including CD34+ hematopoietic stem/progenitor cells. UCB cells were exposed to MW pulsed signals from GSM900/UMTS test-mobile phone and ROS, apoptosis, DNA damage, and PFG were analyzed using flow cytometry, automated fluorescent microscopy, imaging flow cytometry, comet assay, and RT-qPCR. In general, no persisting difference in DNA damage, PFG and apoptosis between exposed and sham-exposed samples was detected. However, we found increased ROS level after 1 h of UMTS exposure that was not evident 3 h post-exposure. We also found that the level of ROS rise with the higher degree of cellular differentiation. Our data show that UCB cells exposed to pulsed MW developed transient increase in ROS that did not result in sustained DNA damage and apoptosis.
Asunto(s)
Teléfono Celular , Sangre Fetal/metabolismo , Células Madre Hematopoyéticas/metabolismo , Leucemia/metabolismo , Microondas/efectos adversos , Lesiones Precancerosas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Daño del ADN , Células Madre Hematopoyéticas/patología , Humanos , Leucemia/patología , Lesiones Precancerosas/patologíaRESUMEN
The study focused on protective potential of phytochemicals applicable in prevention and health protection is of great importance. Various structures of these compounds and a wide range of their biological activities have inspired organic chemists to sythesize their effective analogues in order to further increase their efficacy. The aims of our study were (i) to synthesize phenylethanoid glycopyranosides: salidroside (SALI - tyrosol ß-d-glucopyranoside), tyrosol ß-d-galactopyranoside (TYBGAL), tyrosol α-d-galactopyranoside (TYAGAL), tyrosol α-d-mannopyranoside (TYAMAN), hydroxytyrosol α-d-mannopyranoside (HOTAMA), homosyringyl ß-d-glucopyranoside (HSYGLU), hydroxytyrosol ß-d-xylopyranoside (HOTXYL) and hydroxysalidroside (HOSALI); (ii) to determine their antioxidant capacities (cell-free approaches); (iii) to evaluate their cytotoxicity (MTT test), protectivity against hydrogen peroxide (H2O2; comet assay) and effect on the intracellular glutathione level (iGSH; flow cytometry) in experimental system utilizing human hepatoma HepG2 cells. HOSALI, HOTAMA, HOTXYL and HSYGLU manifested the highest antioxidant capacity in cell-free assays and they were most active in protection of HepG2 cells against H2O2. On the other hand, pre-treatment of HepG2 cells with SALI had protective effects even though SALI displayed almost no activity in cell-free assays. Differences in the efficacy of the analogues revealed that structures of their molecules in terms of aglycone combined with sugar moiety affect their activities.
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Antioxidantes/química , Antioxidantes/farmacología , Glicósidos/química , Glicósidos/farmacología , Monosacáridos/química , Monosacáridos/farmacología , Bioensayo , Compuestos de Bifenilo/química , ADN/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Células Hep G2 , Humanos , Peróxido de Hidrógeno/farmacología , Picratos/química , Plásmidos , Relación Estructura-ActividadRESUMEN
BACKGROUND/AIM: Triple-negative breast cancer (TNBC) constitutes 15-20% of all breast carcinomas, affecting younger women more often and has a worse prognosis than other types of breast cancer, due to the combination of more aggressive clinical behavior and lack of molecular targets for therapy. This study assessed the effects of non-genotoxic concentrations of tributyltin isothiocyanate (TBT-ITC) and triphenyltin isothiocyanate (TPT-ITC) on MDA-MB-231 cells. MATERIALS AND METHODS: MTT assay, comet assay, kinetic imaging and flow cytometry were used for analysis of MDA-MB-231 cells. RESULTS: The results showed that 100 nM concentration of TBT-ITC and TPT-ITC, that did not affect viability or DNA integrity, slowed-down migration by CD44 down-regulation. Moreover, both compounds demonstrated immunomodulatory properties, attenuating PD-L1 expression in MDA-MB-231 cells. CONCLUSION: TPT-ITC was more effective in down-regulating CD44 expression and reducing migration than TBT-ITC, while TBT-ITC was more potent in lowering PD-L1 expression in comparison with TPT-ITC.
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Antineoplásicos/farmacología , Biomarcadores de Tumor , Movimiento Celular/efectos de los fármacos , Isotiocianatos/farmacología , Neoplasias de la Mama Triple Negativas/metabolismo , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Femenino , Humanos , Inmunofenotipificación , Isotiocianatos/química , Compuestos Orgánicos de Estaño/químicaRESUMEN
The cytotoxicity of two recently synthesized triorganotin isothiocyanate derivatives, nuclear retinoid X receptor ligands, was tested and compared in estrogen-receptor-positive MCF 7 and -negative MDA-MB-231 human breast carcinoma cell lines. A 48 h MTT assay indicated that tributyltin isothiocyanate (TBT-ITC) is more cytotoxic than triphenyltin isothiocyanate (TPT-ITC) in MCF 7 cells, and the same trend was observed in the MDA-MB-231 cell line. A comet assay revealed the presence of both crosslinks and increasing DNA damage levels after the 17 h treatment with both derivatives. Differences in cytotoxicity of TBT-ITC and TPT-ITC detected by FDA staining correspond to the MTT data, communicating more pronounced effects in MCF 7 than in the MDA-MB-231 cell line. Both derivatives were found to cause apoptosis, as shown by the mitochondrial membrane potential (MMP) depolarization and caspase-3/7 activation. The onset of caspase activation correlated with MMP dissipation and the total cytotoxicity more than with the amount of active caspases. In conclusion, our data suggest that the DNA damage induced by TBT-ITC and TPT-ITC treatment could underlie their cytotoxicity in the cell lines studied.
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Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Isotiocianatos/farmacología , Compuestos Orgánicos de Estaño/farmacología , Receptores X Retinoide/metabolismo , Compuestos de Trialquiltina/farmacología , Antineoplásicos/química , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Daño del ADN/efectos de los fármacos , Femenino , Humanos , Isotiocianatos/química , Células MCF-7 , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Compuestos Orgánicos de Estaño/química , Compuestos de Trialquiltina/químicaRESUMEN
Natural products represent the source or the inspiration for the majority of the active ingredients of medicines because of their structural diversity and a wide range of biological effects. Our aims in this study were (i) to synthesize enzymatically salidroside (SAL), the most effective phenylethanoid glycoside in Rhodiola species; (ii) to examine its antioxidant capacity using cell-free assays (reducing power, DPPH radicals scavenging and Fe2+ -chelating assays); (iii) to assess its DNA-protective potential on plasmid DNA (DNA topology assay) and in HepG2 cells (comet assay) damaged by Fe2+ ions and hydrogen peroxide, respectively; and (iv) to investigate the effects of SAL, cisplatin (CDDP) and combined treatments of SAL + CDDP on cell viability (MTT test), level of DNA damage (comet assay), proliferation, cell cycle (flow cytometry) and the expression of signalling molecules associated with cell growth and apoptotic pathways (Western immunoblotting). We found out that SAL manifested low antioxidant and DNA-protective capacity in all assays used. In both parental A2780 and CDDP-resistant A2780/CP human ovarian carcinoma cells, SAL itself exerted in fact no impact on the viability, while in combination with CDDP it showed antagonistic effect supporting the chemopreventive activity on the CDDP-induced cell damage. These results were confirmed by the partial reversal of the cell cycle alterations and the DNA damage level, as well as with partial restoration of cell survival/signalling pathways, when the expression of these molecules partially returned to their proper levels.
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Anticarcinógenos/farmacología , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Cisplatino/farmacología , Glucósidos/farmacología , Hepatocitos/efectos de los fármacos , Neoplasias Ováricas/tratamiento farmacológico , Fenoles/farmacología , Antineoplásicos/efectos adversos , Antineoplásicos/química , Antioxidantes/farmacología , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cisplatino/efectos adversos , Cisplatino/agonistas , Cisplatino/antagonistas & inhibidores , Ensayo Cometa , Daño del ADN/efectos de los fármacos , Antagonismo de Drogas , Sinergismo Farmacológico , Femenino , Células Hep G2 , Hepatocitos/citología , Humanos , Neoplasias Ováricas/patología , Sustancias Protectoras/farmacología , Reproducibilidad de los Resultados , Transducción de Señal/efectos de los fármacosRESUMEN
Despite widely accepted notion that many childhood leukemias are likely developed from hematopoietic stem/progenitor cells (HSPC) with pre-leukemic fusion genes (PFG) formed in embryonic/fetal development, the data on PFG incidence in newborns are contradictive. To provide a better understanding of a prenatal origin of leukemia, umbilical cord blood from 500 newborns was screened for the presence of the most frequent PFG associated with pediatric B-cell acute lymphoblastic leukemia. This screening revealed relatively high incidence of ETV6-RUNX1, BCR-ABL1 (p190) and MLL-AF4 at very low frequencies, averaging ~14 copies per 100,000 cells. We assume that most of these PFG might originate relatively late in embryonic/fetal development and will be eliminated later during postnatal development. The obtained results suggested that higher PFG copy numbers originating in specific time windows of the hematopoietic stem cell hierarchy may define a better prognostic tool for the assessment of leukemogenic potential. We have observed no significant effect of low-copy PFG on radiation-induced DNA damage response, accumulation of endogenous DNA double-stranded breaks, and apoptosis in either lymphocytes or HSPC. Imaging flow cytometry showed lower level of γH2AX foci in HSPC in comparison to lymphocytes suggesting better protection of HSPC from DNA damage.
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Ácidos Nucleicos Libres de Células , Daño del ADN , Sangre Fetal , Dosificación de Gen , Proteínas de Fusión Oncogénica/genética , Apoptosis/genética , Apoptosis/efectos de la radiación , Daño del ADN/efectos de la radiación , Reparación del ADN , Humanos , Incidencia , Recién Nacido , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangre , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiología , Leucemia-Linfoma Linfoblástico de Células Precursoras/genéticaRESUMEN
Nature is an attractive source of therapeutic compounds. In comparison to the artificial drugs, natural compounds cause less adverse side effects and are suitable for current molecularly oriented approaches to drug development and their mutual combining. Medicinal plants represent one of the most available remedy against various diseases. Proper examples are Salvia officinalis L. and Thymus vulgaris L. which are known aromatic medicinal plants. They are very popular and frequently used in many countries. The molecular mechanism of their biological activity has not yet been fully understood. The aim of this study was to ascertain if liver cells of experimental animals drinking extracts of sage or thyme will manifest increased resistance against oxidative stress. Adult Sprague-Dawley rats were divided into seven groups. They drank sage or thyme extracts for 2 weeks. At the end of the drinking period, blood samples were collected for determination of liver biochemical parameters and hepatocytes were isolated to analyze (i) oxidatively generated DNA damage (conventional and modified comet assay), (ii) activities of antioxidant enzymes [superoxide dismutase (SOD), glutathione peroxidase (GPx)] and (iii) content of glutathione. Intake of sage and thyme had no effect either on the basal level of DNA damage or on the activity of SOD in rat hepatocytes and did not change the biochemical parameters of blood plasma. Simultaneously, the activity of GPx was significantly increased and the level of DNA damage induced by oxidants was decreased. Moreover, sage extract was able to start up the antioxidant protection expressed by increased content of glutathione. Our results indicate that the consumption of S.officinalis and T.vulgaris extracts positively affects resistency of rat liver cells against oxidative stress and may have hepatoprotective potential.
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Daño del ADN , Hepatocitos/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Salvia officinalis , Thymus (Planta) , Animales , Antioxidantes/farmacología , Ensayo Cometa , Agua Potable , Femenino , Expresión Génica , Glutatión/análisis , Glutatión/efectos de los fármacos , Glutatión Peroxidasa/efectos de los fármacos , Glutatión Peroxidasa/genética , Masculino , Ratas , Ratas Sprague-Dawley , Superóxido Dismutasa/efectos de los fármacos , Superóxido Dismutasa/genéticaRESUMEN
Cisplatin resistance is one of the major obstacles in the treatment of ovarian cancer. In an effort to look for new possibilities of how to overcome this difficulty, we studied the mechanisms of the interactions between sulforaphane (SFN) and cisplatin (cisPt) in combined treatment of human ovarian carcinoma A2780 and SKOV3 cell lines. Synergy (A2780) and antagonism (SKOV3) found in MTT assay was confirmed by apoptosis. While SFN significantly potentiated cisPt-induced DNA damage in A2780 cells, it protected SKOV3 cells against cisPt-crosslinking. We revealed a less efficient Nrf-2 pathway inducibility by SFN in A2780 compared to SKOV3 cells, when activation of the Nrf-2 pathway incites its protectivity against cisPt. Thus, different activation of the Nrf-2 pathway may explain the dual effects of SFN.
Asunto(s)
Antineoplásicos/farmacología , Cisplatino/farmacología , Resistencia a Antineoplásicos , Isotiocianatos/farmacología , Neoplasias Ováricas/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Ensayo Cometa , Daño del ADN/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Neoplasias Ováricas/tratamiento farmacológico , Transducción de Señal , SulfóxidosRESUMEN
Selected components of plant essential oils and intact Rosmarinus officinalis oil (RO) were investigated for their antioxidant, iron-chelating, and DNA-protective effects. Antioxidant activities were assessed using four different techniques. DNA-protective effects on human hepatoma HepG2 cells and plasmid DNA were evaluated with the help of the comet assay and the DNA topology test, respectively. It was observed that whereas eugenol, carvacrol, and thymol showed high antioxidative effectiveness in all assays used, RO manifested only antiradical effect and borneol and eucalyptol did not express antioxidant activity at all. DNA-protective ability against hydrogen peroxide (H2O2)-induced DNA lesions was manifested by two antioxidants (carvacrol and thymol) and two compounds that do not show antioxidant effects (RO and borneol). Borneol was able to preserve not only DNA of HepG2 cells but also plasmid DNA against Fe(2+)-induced damage. This paper evaluates the results in the light of experiences of other scientists.
Asunto(s)
Antioxidantes/análisis , Quelantes/análisis , Daño del ADN/efectos de los fármacos , Aceites Volátiles/química , Aceites de Plantas/química , Rosmarinus/química , Canfanos/farmacología , Ciclohexanoles/farmacología , Cimenos , Eucaliptol , Eugenol/farmacología , Células Hep G2 , Humanos , Peróxido de Hidrógeno/farmacología , Monoterpenos/farmacología , Plásmidos/genética , Timol/farmacologíaRESUMEN
Natural essential oils are volatile herbal complex compounds which manifest cytotoxic effects on living cells depending on their type and concentration but usually they are not genotoxic. Our previous studies showed that carvacrol (CA) and rosemary essential oil (RO) induced growth inhibition of both human cell lines HepG2 and BHNF-1, with hepatoma HepG2 cells being more sensitive to either compound tested. Cytotoxic concentrations of CA and RO induced the formation of DNA strand breaks. Further ex vivo studies showed that extracts prepared from hepatocytes of CA- and RO-supplemented rats did not increase incision repair activity compared to extracts from liver cells of control animals. Therefore, the aim of this work was to determine the effect of cytotoxic concentrations of CA and RO on the cell cycle and the ability of both natural volatiles to induce DNA fragmentation and apoptotic death of human hepatoma HepG2 cells. These effects were measured after 24 h incubation of HepG2 cells with CA and RO using three independent methods - flow cytometry, internucleosomal DNA fragmentation (electrophoresis) and micronucleus assay. Evaluation of morphological changes and formation of micronuclei in HepG2 cells showed no increase in the number of micronuclei in cells treated by CA and RO compared to control cells. On the other hand, CA and RO induced morphological changes typical for apoptosis in concentration-dependent manner. The presence of necrosis was negligible. Both natural compounds caused shrinking of cytoplasmic membrane and formation of apoptotic bodies. In addition, the highest concentrations of CA and RO induced internucleosomal DNA fragmentation (formation of DNA ladder) in HepG2 cells. Cell cycle analysis revealed the accumulation of cells in the G1 phase, which was accompanied by a reduction in the number of cells in the S phase after 24 h exposure to the substances tested. The cell division was thus slowed down or stopped and this process resulted in cell death.
RESUMEN
This paper presents comparisons of biological impacts of the oxidants H2O2 and t-BHP on human liver cells, and shows modulation of these effects by the phenolic compound carvacrol. To understand better how these oxidants exert their effect on DNA and on the activity of the enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx), we measured intracellular antioxidant glutathione (iGSH) and intracellular reactive oxidative species (iROS). DNA lesions corresponded to single-strand DNA breaks, alkali-labile lesions and formamido-pyrimidine-DNA-glycosylase (FPG)-sensitive sites. Pre-treatment of cells with carvacrol substantially decreased the number of H2O2-induced DNA lesions, but the number of t-BHP-induced DNA lesions was not reduced. Activities of both SOD and GPx were stimulated significantly by carvacrol and were reduced by the combined effect of carvacrol and oxidants. H2O2 and t-BHP alone influenced the level of antioxidant enzymes differently. While H2O2 did not markedly change the activity of SOD or GPx, lower concentrations of t-BHP stimulated activity of SOD and mainly GPx. The level of iROS was increased by both oxidants and decreased by carvacrol applied either alone or with oxidants. The level of iGSH was not influenced in any of the treatments tested. Our results show that although both oxidants induced oxidative stress and damaged cellular DNA, their influences on other molecular processes were different. The protective effect of carvacrol against DNA-damaging effects of H2O2 was unambiguous, but reduction by carvacrol of the DNA-damaging effect of t-BHP was not observed. These results suggest that the phenolic compound carvacrol contributes to the defence mechanisms of the human organism, but these beneficial effects are dependent on the origin and source of the actual oxidative stress.
Asunto(s)
Peróxido de Hidrógeno/toxicidad , Monoterpenos/farmacología , Estrés Oxidativo , terc-Butilhidroperóxido/toxicidad , Cimenos , Roturas del ADN de Cadena Simple/efectos de los fármacos , Glutatión/metabolismo , Glutatión Peroxidasa/metabolismo , Células Hep G2/efectos de los fármacos , Humanos , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismoRESUMEN
Salvia officinalis (SO) and Thymus vulgaris (TV) are medicinal plants well known for their curative powers. However, the molecular mechanisms responsible for these abilities of sage and thyme have not been fully understood yet. In this study we investigated the composition and the quantitative estimation of plant extracts, the protective effects of plant extracts against hydrogen peroxide- and 2,3-dimethoxy-1,4-naphthoquinone-induced DNA damage, and levels of enzymatic and non-enzymatic antioxidants (superoxide dismutase, glutathione peroxidase, glutathione) in human HepG2 cells. To measure antioxidative activity of plant extracts we used three assays: 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). The results showed that the oxidant-induced DNA lesions were significantly reduced in cells pre-treated with the plant extracts studied. The observed DNA-protective activity could be explained by both elevation of GPx activity in cells pre-treated with SO and TV and antioxidant activity of SO and TV.
Asunto(s)
Antioxidantes/metabolismo , Daño del ADN/efectos de los fármacos , Oxidantes/toxicidad , Extractos Vegetales/farmacología , Salvia officinalis/química , Thymus (Planta)/química , Glutatión/metabolismo , Glutatión Peroxidasa/metabolismo , Células Hep G2 , Humanos , Peróxido de Hidrógeno/toxicidad , Naftoquinonas/toxicidad , Superóxido Dismutasa/metabolismoRESUMEN
Experimental evidences suggest that most essential oils possess a wide range of biological and pharmacological activities that may protect tissues against oxidative damage. In this study, we investigated DNA-protective effect of borneol, a component of many essential oils, against oxidative DNA damage induced in primary cultures of rat hepatocytes. Borneol was added to drinking water of Sprague-Dawley rats and DNA resistance against oxidative agents was compared in hepatocytes originated from control and borneol-treated rats. Oxidative stress induced by visible light-excited methylene blue (MB/VL) or 2,3-dimethoxy-1,4-naphthoquionone (DMNQ) resulted in increased levels of DNA lesions measured by the modified single cell gel electrophoresis. Borneol (17 or 34 mg/kg body weight) added to drinking water of rats for 7 days reduced the level of oxidative DNA lesions induced in their hepatocytes by MB/VL or DMNQ. To explain the increased resistance of DNA towards oxidative stress, we measured the base-excision repair (BER) capacity in liver cell extracts of control and borneol-supplemented rats on DNA substrate of HepG2 cells containing oxidative damage. Our results showed that administration of borneol in drinking water had no effect on incision activity of hepatocytes isolated from supplemented rats. The spectrophotometric assessment of enzymatic antioxidants superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities and the flow cytometric assessment of total intracellular glutathione (iGSH) in primary hepatocytes of borneol-supplemented rats showed no changes in SOD and GPx activities but higher iGSH content particularly in hepatocytes of higher borneol dose (34 mg/kg) supplemented rats in comparison to control animals. Despite the fact that borneol had no effect either on BER of oxidative DNA damage or on the levels of antioxidant enzymes and manifested no reducing power and radicals scavenging activity, it increased significantly the level of non-enzymatic antioxidant iGSH which could reduce the oxidative DNA lesions induced by MB/VL or DMNQ.