Rabbit cornea
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Corneal alkali burns are potentially blinding injuries. Alkali induces oxidative stress in corneas followed by excessive corneal inflammation, neovascularization, and untransparent scar formation. Molecular hydrogen (H2), a potent reactive oxygen species (ROS) scavenger, suppresses oxidative stress and enables corneal healing when applied on the corneal surface. The purpose of this study was to examine whether the H2 pretreatment of healthy corneas evokes a protective effect against corneal alkali-induced oxidative stress. Rabbit eyes were pretreated with a H2 solution or buffer solution, by drops onto the ocular surface, and the corneas were then burned with 0.25 M NaOH. The results obtained with immunohistochemistry and pachymetry showed that in the corneas of H2-pretreated eyes, slight oxidative stress appeared followed by an increased expression of antioxidant enzymes. When these corneas were postburned with alkali, the alkali-induced oxidative stress was suppressed. This was in contrast to postburned buffer-pretreated corneas, where the oxidative stress was strong. These corneas healed with scar formation and neovascularization, whereas corneas of H2-pretreated eyes healed with restoration of transparency in the majority of cases. Corneal neovascularization was strongly suppressed. Our results suggest that the corneal alkali-induced oxidative stress was reduced via the increased antioxidant capacity of corneal cells against reactive oxygen species (ROS). It is further suggested that the ability of H2 to induce the increase in antioxidant cell capacity is important for eye protection against various diseases or external influences associated with ROS production.
- MeSH
- alkálie toxicita MeSH
- antioxidancia metabolismus MeSH
- chemické popálení farmakoterapie metabolismus patologie MeSH
- epitelové buňky účinky léků metabolismus patologie MeSH
- hojení ran účinky léků MeSH
- králíci MeSH
- modely nemocí na zvířatech MeSH
- neovaskularizace rohovky prevence a kontrola MeSH
- oxidační stres účinky léků MeSH
- popálení oka chemicky indukované farmakoterapie metabolismus patologie MeSH
- reaktivní formy kyslíku metabolismus MeSH
- rohovka krevní zásobení účinky léků metabolismus patologie MeSH
- vodík farmakologie terapeutické užití MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Our previous research revealed that trehalose, a nonreducing disaccharide of glucose and an important stress responsive factor, proved to have anti-inflammatory, antiapoptotic, and particularly antioxidant properties in UVB-irradiated corneas. Trehalose reduced oxidative stress in corneas induced by UVB irradiation, by means of a decrease in the antioxidant/prooxidant imbalance in the corneal epithelium. In this study, we demonstrate that trehalose of 3% or 6% concentration in eye drops directly decreases oxidative stress in UVB-irradiated corneas, by removing the excessive amount of reactive oxygen species (ROS). Trehalose drops applied on corneas during UVB irradiation once daily for four days resulted in a reduction or even absence of the oxidative stress, DNA damage, and peroxynitrite formation (detected by nitrotyrosine residues), seen in buffer-treated corneas. Furthermore, trehalose treatment applied curatively after repeated irradiation for the subsequent fourteen days led to the renewal of corneal transparency and significant suppression or even absence of neovascularization. This was in contrast to buffer-treated irradiated corneas, where the intracorneal inflammation was developed and the untransparent corneas were vascularized. In conclusion, the treatment of UVB-irradiated corneas with trehalose eye drops removed the excessive amount of ROS in the corneal epithelium, leading to the suppression of oxidative stress and favorable corneal healing. The 6% trehalose showed a higher intensive antioxidant effect.
- MeSH
- hojení ran účinky léků účinky záření MeSH
- interleukin-1beta metabolismus MeSH
- keratiny metabolismus MeSH
- králíci MeSH
- oxidační stres * účinky léků účinky záření MeSH
- poranění rohovky farmakoterapie MeSH
- poškození DNA MeSH
- reaktivní formy kyslíku metabolismus MeSH
- reepitalizace účinky léků účinky záření MeSH
- rohovka účinky léků patologie účinky záření MeSH
- synthasa oxidu dusnatého, typ II metabolismus MeSH
- trehalosa farmakologie terapeutické užití MeSH
- tyrosin analogy a deriváty metabolismus MeSH
- ultrafialové záření * MeSH
- vaskulární endoteliální růstový faktor A metabolismus MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Trehalose, a disaccharide of glucose, is a naturally occurring nontoxic and nonreducing bioactive sugar. Trehalose is synthetized by many organisms when cells are exposed to stressful conditions, including dehydration, heat, oxidation, hypoxia or even anoxia. Although trehalose is not synthesized by mammalian cells, it has recently been demonstrated to have a number of important properties that indicate its utility in humans. Trehalose enables wound healing by protecting cells, especially cell membranes, from oxidative injury and dessication. When the injured cornea is treated with trehalose, corneal inflammation, scar formation and corneal neovascularization are suppressed. In dry eye disease, trehalose decreased cell apoptosis and reduced oxidative, inflammatory and proteolytic activity at the ocular surface. In UVB irradiated cornea, trehalose suppressed photodamage evoked by UVB rays. It decreased the intracorneal inflammation and reduced corneal neovascularization. Trehalose prevented postoperative fibrous scar formation after ocular surgery, such as glaucoma filtration surgery. The non-toxicity of trehalose allows its administration in humans for extended periods and enables its use in various disease states.
- MeSH
- antiflogistika chemie farmakologie MeSH
- antioxidancia chemie farmakologie MeSH
- apoptóza * MeSH
- hojení ran * MeSH
- klinické zkoušky jako téma MeSH
- králíci MeSH
- lidé MeSH
- modely nemocí na zvířatech MeSH
- oftalmologie MeSH
- oxidační stres * MeSH
- rohovka účinky léků účinky záření MeSH
- syndromy suchého oka farmakoterapie MeSH
- trehalosa chemie farmakologie MeSH
- ultrafialové záření MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
The aim of this study is to examine whether molecular hydrogen (H2) is able to reduce oxidative stress after corneal damage induced by UVB irradiation. We previously found that UVB irradiation of the cornea caused the imbalance between the antioxidant and prooxidant enzymes in the corneal epithelium, followed by the imbalance between metalloproteinases and their physiological inhibitors (imbalances in favour of prooxidants and metalloproteinases) contributing to oxidative stress and development of the intracorneal inflammation. Here we investigate the effect of H2 dissolved in PBS in the concentration 0.5 ppm wt/vol, applied on rabbit corneas during UVB irradiation and healing (UVB doses 1.01 J/cm2 once daily for four days). Some irradiated corneas remained untreated or buffer treated. In these corneas the oxidative stress appeared, followed by the excessive inflammation. Malondiladehyde and peroxynitrite expressions were present. The corneas healed with scar formation and neovascularization. In contrast, in H2 treated irradiated corneas oxidative stress was suppressed and malondiladehyde and peroxynitrite expressions were absent. The corneas healed with the restoration of transparency. The study provides the first evidence of the role of H2 in prevention of oxidative and nitrosative stress in UVB irradiated corneas, which may represent a novel prophylactic approach to corneal photodamage.
- MeSH
- králíci MeSH
- kyselina peroxydusitá metabolismus MeSH
- malondialdehyd metabolismus MeSH
- oxidační stres účinky léků účinky záření MeSH
- poranění rohovky farmakoterapie metabolismus MeSH
- reaktivní formy kyslíku metabolismus MeSH
- rohovka účinky léků metabolismus účinky záření MeSH
- ultrafialové záření * MeSH
- vodík terapeutické užití MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- odvolaná publikace MeSH
- práce podpořená grantem MeSH
- MeSH
- akutní nemoc MeSH
- blefarospazmus diagnóza etiologie veterinární MeSH
- cizí těleso v oku * diagnóza terapie veterinární MeSH
- kočky MeSH
- králíci MeSH
- morčata MeSH
- poranění rohovky * diagnóza etiologie prevence a kontrola veterinární MeSH
- psi MeSH
- reakce na cizí těleso veterinární MeSH
- zvířata MeSH
- Check Tag
- kočky MeSH
- králíci MeSH
- morčata MeSH
- psi MeSH
- zvířata MeSH
- Publikační typ
- kazuistiky MeSH
The aim of this study was to examine the effect of molecular hydrogen (H2) on the healing of alkali-injured cornea. The effects of the solution of H2 in phosphate buffered saline (PBS) or PBS alone topically applied on the alkali-injured rabbit cornea with 0.25 M NaOH were investigated using immunohistochemical and biochemical methods. Central corneal thickness taken as an index of corneal hydration was measured with an ultrasonic pachymeter. Results show that irrigation of the damaged eyes with H2 solution immediately after the injury and then within next five days renewed corneal transparency lost after the injury and reduced corneal hydration increased after the injury to physiological levels within ten days after the injury. In contrast, in injured corneas treated with PBS, the transparency of damaged corneas remained lost and corneal hydration elevated. Later results-on day 20 after the injury-showed that in alkali-injured corneas treated with H2 solution the expression of proinflammatory cytokines, peroxynitrite, detected by nitrotyrosine residues (NT), and malondialdehyde (MDA) expressions were very low or absent compared to PBS treated injured corneas, where NT and MDA expressions were present. In conclusion, H2 solution favorably influenced corneal healing after alkali injury via suppression of oxidative stress.
- MeSH
- aktiny metabolismus MeSH
- cytokiny metabolismus MeSH
- exprese genu účinky léků MeSH
- hydroxid sodný toxicita MeSH
- imunohistochemie MeSH
- interleukin-1beta genetika metabolismus MeSH
- keratin-12 metabolismus MeSH
- keratin-3 metabolismus MeSH
- králíci MeSH
- kyselina peroxydusitá metabolismus MeSH
- malondialdehyd metabolismus MeSH
- modely nemocí na zvířatech MeSH
- oxidační stres účinky léků MeSH
- poranění rohovky etiologie metabolismus patologie MeSH
- rohovka metabolismus patologie MeSH
- vaskulární endoteliální růstový faktor A genetika metabolismus MeSH
- vodík farmakologie MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The Purpose of present study was to investigate the effect of riboflavin/ultraviolet-A-induced collagen cross-linking (CXL) on central cornea, limbus and intraocular pressure (IOP). This was an animal experimental study. The right corneas of 10 rabbits were ultraviolet-A irradiated (3 mW/cm2 for 30 minutes) after de-epithelialization and instillation of 0.1% riboflavin / 20% Dextran drops. Left corneas served as controls. Samples were examined histologically one month postoperatively. Before and after treatment, IOP measurements were recorded bilaterally. At central cornea of eyes underwent CXL keratocyte repopulation, normal arrangement of collagen fibres and a statistically significant change in fibres diameter were detected, compared to controls. At limbus area, there were not any significant histological differences after CXL. There was no statistically significant difference between pre- and postoperative IOP in all eyes.
- MeSH
- fotosenzibilizující látky farmakologie MeSH
- kolagen chemie ultrastruktura MeSH
- králíci MeSH
- limbus corneae účinky léků účinky záření chirurgie ultrastruktura MeSH
- nitrooční tlak * účinky léků účinky záření MeSH
- reagencia zkříženě vázaná farmakologie MeSH
- riboflavin farmakologie MeSH
- rohovka účinky léků účinky záření chirurgie ultrastruktura MeSH
- ultrafialové záření * MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
In this study we tried to develop a new approach to suppress inflammation and neovascularization in the alkali-injured rabbit cornea. For this reason Cyclosporine A (CsA)-loaded electrospun nanofibers were transferred onto the ocular surface injured with alkali (0.25 N NaOH). Damaged corneas were divided into the following groups: untreated, treated with CsA eye drops, treated with nanofibers drug-free and treated with CsA-loaded nanofibers. Healthy rabbit corneas served as controls. Drug-free nanofibers and CsA-loaded nanofibers were transferred onto the damaged corneal surface immediately after the injury and sutured to conjunctiva. On day five after the injury the nanofibers were removed. The animals from all groups were sacrificed on day twelve after the injury. The extent of the inflammatory reaction and corneal healing were examined macroscopically, immunohistochemically and biochemically. The central corneal thickness was measured using an ultrasonic pachymeter. When compared with untreated injured corneas, injured corneas treated with drug-free nanofibers or injured corneas treated with CsA eye drops, the number of CD3-positive cells (T lymphocytes) and the production of pro-inflammatory cytokines were strongly reduced in corneas treated with CsA-loaded nanofibers, which was associated with the significantly decreased expression of matrix metalloproteinase 9, inducible nitric oxide synthase, vascular endothelial growth factor and active caspase-3. CsA-loaded nanofibers effectively suppressed corneal inflammation and corneal neovascularization. Central corneal thickness restored to levels before injury only in corneas treated with CsA-loaded nanofibers. Corneal transparency was highly restored in these corneas. It is suggested that the beneficial effect of CsA-loaded nanofibers was associated with the continuous release of CsA from nanofibers and continuous affection of damaged cornea by CsA. The suture of nanofibers to conjunctiva and the closed eyes contributed to beneficial corneal healing. This is in contrast to CsA eye drops, which are quickly washed from the ocular surface and the contact of CsA with the damaged cornea was limited. In conclusion, the approach with CsA-loaded nanofibers could represent an effective alternative mode of therapy for corneal chemical burns.
- MeSH
- alkálie škodlivé účinky MeSH
- chemické popálení farmakoterapie MeSH
- cyklosporin aplikace a dávkování terapeutické užití MeSH
- imunohistochemie MeSH
- imunosupresiva terapeutické užití MeSH
- kaspasa 3 metabolismus MeSH
- králíci MeSH
- modely nemocí na zvířatech MeSH
- nanovlákna MeSH
- neovaskularizace rohovky patologie MeSH
- popálení oka farmakoterapie metabolismus patologie MeSH
- poranění rohovky chemicky indukované metabolismus patologie MeSH
- T-lymfocyty patologie MeSH
- vaskulární endoteliální růstový faktor A metabolismus MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The aim of this study was to examine whether nanofiber scaffolds seeded with rabbit bone marrow mesenchymal stem cells (MSCs nanofibers) transferred onto the damaged corneal surface and covered with cyclosporine A (CsA)-loaded nanofiber scaffolds (CsA nanofibers) enable healing of the rabbit cornea injured with 1N NaOH. The healing of damaged corneas was examined morphologically, immunohistochemically and biochemically on day 24 after the injury. Compared to untreated injured corneas, where corneal ulceration or large corneal thinning or even perforation were developed, injured corneas treated with drug free nanofibers healed without profound disturbances in a majority of cases, although with fibrosis and scar formation. In injured corneas treated with CsA nanofibers or MSCs nanofibers, the development of scar formation was reduced. Best healing results were obtained with a combination of MSCs and CsA nanofibers (MSCs-CsA nanofibers). Corneas healed with highly restored transparency. Neovascularization highly expressed in untreated injured corneas and reduced in corneas treated with CsA nanofibers or MSCs nanofibers, was suppressed in corneas treated with MSCs-CsA nanofibers. The levels of matrix metalloproteinase 9, inducible nitric oxide synthase, interleukin 6, α-smooth muscle actin, tumor growth factor β and vascular endothelial growth factor were significantly decreased in these corneas as compared to untreated corneas, where the levels of the above mentioned markers were high. In conclusion, MSCs-CsA nanofibers were effective in the treatment of severe alkali-induced corneal injury.
- MeSH
- cyklosporin aplikace a dávkování MeSH
- hojení ran účinky léků MeSH
- hydroxid sodný toxicita MeSH
- imunosupresiva aplikace a dávkování MeSH
- jizva prevence a kontrola MeSH
- kaustika toxicita MeSH
- králíci MeSH
- lékové transportní systémy metody MeSH
- modely nemocí na zvířatech MeSH
- nanovlákna MeSH
- neovaskularizace rohovky prevence a kontrola MeSH
- nosiče léků MeSH
- poranění rohovky terapie MeSH
- tkáňové podpůrné struktury MeSH
- transplantace mezenchymálních kmenových buněk metody MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The aim of this study was to examine whether mesenchymal stem cells (MSCs) and/or corneal limbal epithelial stem cells (LSCs) influence restoration of an antioxidant protective mechanism in the corneal epithelium and renewal of corneal optical properties changed after alkali burns. The injured rabbit corneas (with 0.25 N NaOH) were untreated or treated with nanofiber scaffolds free of stem cells, with nanofiber scaffolds seeded with bone marrow MSCs (BM-MSCs), with adipose tissue MSCs (Ad-MSCs), or with LSCs. On day 15 following the injury, after BM-MSCs or LSCs nanofiber treatment (less after Ad-MSCs treatment) the expression of antioxidant enzymes was restored in the regenerated corneal epithelium and the expressions of matrix metalloproteinase 9 (MMP9), inducible nitric oxide synthase (iNOS), α-smooth muscle actin (α-SMA), transforming growth factor-β1 (TGF-β1), and vascular endothelial factor (VEGF) were low. The central corneal thickness (taken as an index of corneal hydration) increased after the injury and returned to levels before the injury. In injured untreated corneas the epithelium was absent and numerous cells revealed the expressions of iNOS, MMP9, α-SMA, TGF-β1, and VEGF. In conclusion, stem cell treatment accelerated regeneration of the corneal epithelium, restored the antioxidant protective mechanism, and renewed corneal optical properties.
- MeSH
- alkálie MeSH
- antioxidancia terapeutické užití MeSH
- buněčná diferenciace účinky léků MeSH
- chemické popálení enzymologie genetika patologie terapie MeSH
- imunohistochemie MeSH
- králíci MeSH
- limbus corneae cytologie MeSH
- matrixová metaloproteinasa 9 metabolismus MeSH
- mezenchymální kmenové buňky cytologie účinky léků MeSH
- ochranné látky farmakologie terapeutické užití MeSH
- pachymetrie rohovky MeSH
- regulace genové exprese účinky léků MeSH
- rohovkový epitel patologie MeSH
- superoxiddismutasa metabolismus MeSH
- synthasa oxidu dusnatého, typ II metabolismus MeSH
- transformující růstový faktor beta genetika metabolismus MeSH
- transplantace mezenchymálních kmenových buněk * MeSH
- tukové buňky cytologie účinky léků MeSH
- vaskulární endoteliální růstový faktor A metabolismus MeSH
- zákal rohovky komplikace terapie MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH