Effects of low-frequency electromagnetic fields (LF EMF) on the activation of different tissue recovery processes have already been fully understood. Preliminary recent data demonstrated that a special case of sinusoidal electromagnetic fields, known as amplitude-modulated currents (AMC) could have a potential to accelerate the cell metabolism or cell migration. An AMC generator was designed to generate sinusoidal induced electric currents with the amplitude modulation and the harmonic carrier frequency of 5,000 Hz was modulated by frequencies of 1 to 100 Hz. The magnetic field peak was 6 mT, electric field intensity 2 V/m and the current density of induced electrical currents was approximately 1 A/m(2). The coil of the generator was adapted to easy handling and safe integration into the shelf of the CO(2) incubator. The shelf with the coil was prepared for the introduction of cells in standard plastic in vitro chambers. The tests focused on cells with migratory capacity after injury or during immunological processes and thus, mesenchymal stromal cells (MSC), dendritic cells (DC), and fibroblasts were chosen. The tests involved exposures of the cells to LF EMF (180 min/day) every day, for a period of three days, before examining them for cell death, morphology changes, and CD markers. The samples were tested by using MTT assay and the effects on the intracellular concentration of reactive oxygen species were quantified. The cell migration was finally measured with the help of the transwell migration assay. None of the cell types showed any decrease in the cell viability after the LF EMF application and the cells displayed minimum changes in reactive oxygen species. Functional changes (acceleration of cell migration) after AMC exposure were statistically significant for the MSC samples only. The acceleration of MSCs is associated with the production of MMP by these cells. The EMF has a potential to be a safe, clinically applicable selective activator of MSC homing, MSC paracrine production, and subsequent regeneration processes.
- MeSH
- buňky 3T3 MeSH
- dendritické buňky fyziologie MeSH
- elektromagnetická pole * MeSH
- fibroblasty fyziologie MeSH
- lidé MeSH
- matrixová metaloproteinasa 2 metabolismus MeSH
- mezenchymální kmenové buňky fyziologie MeSH
- myši MeSH
- parakrinní signalizace MeSH
- pohyb buněk * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
2,3-dehydrosilybin (DHS) is a minor component of silymarin, Silybum marianum seed extract, used in some dietary supplements. One of the most promising activities of this compound is its anticancer and cardioprotective activity that results, at least partially, from its cytoprotective, antioxidant, and chemopreventive properties. The present study investigated the cardioprotective effects of DHS in myocardial ischemia and reperfusion injury in rats. Isolated hearts were perfused by the Langendorff technique with low dose DHS (100 nM) prior to 30 min of ischemia induced by coronary artery occlusion. After 60 min of coronary reperfusion infarct size was determined by triphenyltetrazolium staining, while lactatedehydrogenase activity was evaluated in perfusate samples collected at several timepoints during the entire perfusion procedure. Signalosomes were isolated from a heart tissue after reperfusion and involved signalling proteins were detected. DHS reduced the extent of infarction compared with untreated control hearts at low concentration; infarct size as proportion of ischemic risk zone was 7.47 ± 3.1% for DHS versus 75.3 ± 4.8% for ischemia. This protective effect was comparable to infarct limitation induced by ischemic preconditioning (22.3 ± 4.5%). Selective inhibition of Src-family kinases with PP2 (4-Amino-3-(4-chlorophenyl)-1-(t-butyl)-1H-pyrazolo[3,4-d]pyrimidine) abrogated the protection afforded by DHS. This study provides experimental evidence that DHS can mediate Src-kinase-dependent cardioprotection against myocardial damage produced by ischemia/reperfusion injury.
- MeSH
- infarkt myokardu farmakoterapie MeSH
- kardiotonika farmakologie MeSH
- krysa rodu rattus MeSH
- potkani Wistar MeSH
- reperfuzní poškození farmakoterapie MeSH
- silymarin farmakologie MeSH
- srdce účinky léků MeSH
- techniky in vitro MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The exposure of naked unprotected skin to solar radiation may result in numerous acute and chronic undesirable effects. Evidence suggests that silymarin, a standardized extract from Silybum marianum (L.) Gaertn. seeds, and its major component silybin suppress UVB-induced skin damage. Here, we aimed to investigate the UVA-protective effects of silymarin's less abundant flavonolignans, specifically isosilybin (ISB), silychristin (SC), silydianin (SD), and 2,3-dehydrosilybin (DHSB). Normal human dermal fibroblasts (NHDF) pre-treated for 1 h with flavonolignans were then exposed to UVA light using a solar simulator. Their effects on reactive oxygen species (ROS), carbonylated proteins and glutathione (GSH) level, caspase-3 activity, single-strand breaks' (SSBs) formation and protein level of matrix metalloproteinase-1 (MMP-1), heme oxygenase-1 (HO-1), and heat shock protein (HSP70) were evaluated. The most pronounced preventative potential was found for DHSB, a minor component of silymarin, and SC, the second most abundant flavonolignan in silymarin. They had significant effects on most of the studied parameters. Meanwhile, a photoprotective effect of SC was mostly found at double the concentration of DHSB. ISB and SD protected against GSH depletion, the generation of ROS, carbonylated proteins and SSBs, and caspase-3 activation, but had no significant effect on MMP-1, HO-1, or HSP70. In summary, DHSB and to a lesser extent other silymarin flavonolignans are potent UVA-protective compounds. However, due to the in vitro phototoxic potential of DHSB published elsewhere, further studies are needed to exclude phototoxicity for humans as well as to confirm our results on human skin ex vivo and in vivo.
- MeSH
- cytoprotekce účinky léků MeSH
- fibroblasty účinky léků účinky záření MeSH
- glutathion metabolismus MeSH
- hemoxygenasa-1 metabolismus MeSH
- jednořetězcové zlomy DNA účinky záření MeSH
- karbonylace proteinů účinky záření MeSH
- kaspasa 3 metabolismus MeSH
- kultivované buňky MeSH
- kůže účinky záření MeSH
- lidé MeSH
- matrixová metaloproteinasa 1 metabolismus MeSH
- přípravky chránící proti slunci farmakologie MeSH
- proteiny tepelného šoku HSP70 metabolismus MeSH
- reaktivní formy kyslíku metabolismus MeSH
- silymarin analogy a deriváty farmakologie MeSH
- ultrafialové záření škodlivé účinky MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Exposure to solar radiation is a major cause of environmental human skin damage. The main constituent of solar UV light is UVA radiation (320-400 nm); however, the need for protection against UVA has been marginalized for a long time. As a result, there is still a lack of useful agents for UVA protection. In this study, the effect of silymarin (SM) and its main constituent silybin (SB) pre-treatment on UVA-stimulated damage to primary human dermal fibroblasts were carried out. The cells were pre-treated for 1 h with SB or SM and then were exposed to UVA light, using a solar simulator. The effect of SB and SM on reactive oxygen species (ROS) and glutathione (GSH) level, caspase-3 activity, single-strand breaks (SSB) formation and protein level of matrix metalloproteinase-1 (MMP-1), heme oxygenase-1 (HO-1), and heat shock protein (HSP70) was evaluated. Treatment with both SM and SB resulted in a reduction in UVA-stimulated ROS generation and SSB production, as well as in the prevention of GSH depletion, a decrease in the activation of caspase-3 and protein level of MMP-1. They also moderately increased HO-1 level and reduced HSP70 level. Our data showed that both SM and SB are non-phototoxic and have UVA-photoprotective potential and could be useful agents for UV-protective dermatological preparations.
- MeSH
- fibroblasty účinky léků patologie účinky záření MeSH
- glutathion metabolismus MeSH
- hemoxygenasa-1 metabolismus MeSH
- kaspasa 3 metabolismus MeSH
- kultivované buňky MeSH
- kůže patologie účinky záření MeSH
- lidé MeSH
- matrixová metaloproteinasa 1 metabolismus MeSH
- poškození DNA MeSH
- primární buněčná kultura MeSH
- proteiny tepelného šoku HSP70 metabolismus MeSH
- radiační poranění farmakoterapie MeSH
- reaktivní formy kyslíku metabolismus MeSH
- silibinin MeSH
- silymarin terapeutické užití MeSH
- sluneční záření MeSH
- ultrafialové záření škodlivé účinky MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Ischemic postconditioning and remote conditioning are potentially useful tools for protecting ischemic myocardium. This study tested the hypothesis that 2,3-dehydrosilybin (DHS), a flavonolignan component of Silybum marianum, could attenuate cardiomyocyte damage following hypoxia/reoxygenation by decreasing the generation of reactive oxygen species (ROS). After 5-6 days of cell culture in normoxic conditions the rat neonatal cardiomyocytes were divided into four groups. Control group (9 h at normoxic conditions), hypoxia/reoxygenation group (3 h at 1 % O₂, 94 % N₂and 5 % CO₂followed by 10 min of 10 micromol·l⁻¹DHS and 6 h of reoxygenation in normoxia) and postconditioning group (3 h of hypoxia, three cycles of 5 min reoxygenation and 5 min hypoxia followed by 6 h of normoxia). Cell viability assessed by propidium iodide staining was decreased after DHS treatment consistent with increased levels of lactatedehydrogenase (LDH) after reoxygenation. LDH leakage was significantly reduced when cardiomyocytes in the H/Re group were exposed to DHS. DHS treatment reduced H₂O₂production and also decreased the generation of ROS in the H/Re group as evidenced by a fluorescence indicator. DHS treatment reduces reoxygenation-induced injury in cardiomyocytes by attenuation of ROS generation, H₂O₂and protein carbonyls levels. In addition, we found that both the postconditioning protocol and the DHS treatment are associated with restored ratio of phosphorylated/total protein kinase C epsilon, relative to the H/Re group. In conclusion, our data support the protective role of DHS in hypoxia/reperfusion injury and indicate that DHS may act as a postconditioning mimic.
- MeSH
- antioxidancia farmakologie MeSH
- cytoprotekce MeSH
- fosforylace MeSH
- ischemické přivykání MeSH
- karbonylace proteinů účinky léků MeSH
- kardiomyocyty účinky léků metabolismus patologie MeSH
- kultivované buňky MeSH
- L-laktátdehydrogenasa metabolismus MeSH
- novorozená zvířata MeSH
- oxidační stres účinky léků MeSH
- peroxid vodíku metabolismus MeSH
- potkani Wistar MeSH
- proteinkinasa C-epsilon metabolismus MeSH
- reperfuzní poškození myokardu metabolismus patologie prevence a kontrola MeSH
- signální transdukce účinky léků MeSH
- silymarin farmakologie MeSH
- viabilita buněk účinky léků MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Reactive oxygen species (ROS) originating from mitochondria are perceived as a factor contributing to cell aging and means have been sought to attenuate ROS formation with the aim of extending the cell lifespan. Silybin and dehydrosilybin, two polyphenolic compounds, display a plethora of biological effects generally ascribed to their known antioxidant capacity. When investigating the cytoprotective effects of these two compounds in the primary cell cultures of neonatal rat cardiomyocytes, we noted the ability of dehydrosilybin to de-energize the cells by monitoring JC-1 fluorescence. Experiments evaluating oxygen consumption and membrane potential revealed that dehydrosilybin uncouples the respiration of isolated rat heart mitochondria albeit with a much lower potency than synthetic uncouplers. Furthermore, dehydrosilybin revealed a very high potency in suppressing ROS formation in isolated rat heart mitochondria with IC(50) = 0.15 μM. It is far more effective than its effect in a purely chemical system generating superoxide or in cells capable of oxidative burst, where the IC(50) for dehydrosilybin exceeds 50 μM. Dehydrosilybin also attenuated ROS formation caused by rotenone in the primary cultures of neonatal rat cardiomyocytes. We infer that the apparent uncoupler-like activity of dehydrosilybin is the basis of its ROS modulation effect in neonatal rat cardiomyocytes and leads us to propose a hypothesis on natural ischemia preconditioning by dietary polyphenols.
- MeSH
- analýza rozptylu MeSH
- benzimidazoly MeSH
- fluorescenční barviva MeSH
- inhibiční koncentrace 50 MeSH
- karbocyaniny MeSH
- kardiomyocyty metabolismus MeSH
- krysa rodu rattus MeSH
- mitochondrie metabolismus MeSH
- molekulární struktura MeSH
- potkani Wistar MeSH
- reaktivní formy kyslíku metabolismus MeSH
- rotenon toxicita MeSH
- silymarin chemie farmakologie MeSH
- spotřeba kyslíku účinky léků MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Myocardial ischemia/reperfusion (IR) injury leads to structural changes in the heart muscle later followed by functional decline due to progressive fibrous replacement. Hence approaches to minimize IR injury are devised, including ischemic pre-and postconditioning. Mild uncoupling of oxidative phosphorylation is one of the mechanisms suggested to be cardioprotective as chemical uncoupling mimics ischemic preconditioning. Uncoupling protein 2 is proposed to be the physiological counterpart of chemical uncouplers and is thought to be a part of the protective machinery of cardiomyocytes. Morphological changes in the mitochondrial network likely accompany the uncoupling with mitochondrial fission dampening the signals leading to cardiomyocyte death. Here we review recent data on the role of uncoupling in cardioprotection and propose that low concentrations of dietary polyphenols may elicit the same cardioprotective effect as dinitrophenol and FCCP, perhaps accounting for the famed "French paradox".
- MeSH
- buněčná smrt účinky léků MeSH
- dinitrofenoly terapeutické užití MeSH
- fenoly terapeutické užití MeSH
- flavonoidy terapeutické užití MeSH
- iontové kanály metabolismus MeSH
- ischemické přivykání MeSH
- karbonylkyanid-p-trifluormethoxyfenylhydrazon terapeutické užití MeSH
- kardiomyocyty metabolismus patologie MeSH
- kardiotonika terapeutické užití MeSH
- lidé MeSH
- mitochondriální proteiny metabolismus MeSH
- myokard metabolismus patologie MeSH
- oxidativní fosforylace MeSH
- reperfuzní poškození myokardu farmakoterapie metabolismus patologie MeSH
- rozpřahující látky terapeutické užití MeSH
- signální transdukce účinky léků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
Background: Discovery of uncoupling protein 2 (UCP2) in 1997 and demonstration of its wide tissue expressionhas triggered an important question about controlled oxidative phosphorylation uncoupling and the physiologicalfunction of this process. Uncoupling protein 2 (UcP2) is a mitochondrial protein that can infl uence the mitochondrialmembrane potential and hence the production of reactive oxygen species by mitochondria. It is also thought to beinvolved in apoptotic signaling pathways and it has been suggested to be important in cardio- and neuroprotection.Methods and results: We examined the recent literature (2003–2007) in the MedLine database for evidence linkingp38, one of the stress-related protein kinases, with modulation of UCP2 expression in the heart. While two reportsclearly demonstrate p38 as down-regulating UcP2 expression, only circumstantial evidence exists for cardiomyocytes.Confl icting results on p38-regulated cardiomyocyte survival after ischemia leave an open venue for hypotheses on thediff erential regulation of protein expression, including UCP2. Conclusions: Reviewing the evidence connecting UCP2 and its cytoprotective activities, we propose a tissue specifi clink that may explain the variable infl uence of p38 via modulation of UCP2 expression.
- MeSH
- financování organizované MeSH
- iontové kanály MeSH
- ischemická choroba srdeční enzymologie MeSH
- kardiomyocyty metabolismus účinky léků MeSH
- kardiotonika farmakologie terapeutické užití MeSH
- lidé MeSH
- medicína založená na důkazech MeSH
- MEDLINE využití MeSH
- mitochondriální proteiny MeSH
- mitogenem aktivované proteinkinasy p38 MeSH
- oxidativní fosforylace MeSH
- reaktivní formy kyslíku chemie metabolismus MeSH
- rozpřahující látky chemie MeSH
- viabilita buněk účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
Cell death-inducing DFF[DNA fragmentation factor]-like effector-a (CIDEa), may initiate apoptosis by disrupting a complex consisting of 40-kDa caspase-3-activated nuclease (DFF40/CAD) and its 45-kDa inhibitor (DFF45/ICAD). CIDEa, however, was found to be localized in mitochondria. We have performed immunodetection of CIDEa in whole cells and subcellular fractions of HeLa cells adapted for a tetracycline-inducible CIDEa expression. Using immunocytochemistry we observed redistribution, enhanced upon treatment with camptothecin or valinomycin, of CIDEa to nucleus. Similarly, CIDEa content increased in the nuclear fraction but decreased in cytosolic fraction in cells treated to initiate apoptosis. We hypothesize that CIDEa is sequestered in mitochondria while transfer of this potentially dangerous protein from mitochondria into nucleus intensifies or even initiates apoptosis.
