Enhanced expression of the growth-regulated calcyclin gene during corneal wound healing (original) (raw)
Related papers
Scientific Reports
Proper wound healing is dynamic in order to maintain the corneal integrity and transparency. Impaired or delayed corneal epithelial wound healing is one of the most frequently observed ocular defect and difficult to treat. Cyclin dependen kinase (cdk), a known cell cycle regulator, required for proper proliferating and migration of cell. We therefore investigated the role of cell cycle regulator cdk10, member of cdk family and its functional association with transcriptional factor (ETS2) at active phase of corneal epithelial cell migration. Our data showed that cdk10 was associated with ETS2, while its expression was upregulated at the active phase (18 hours) of cell migration and gradually decrease as the wound was completely closed. Topical treatment with anti-cdk10 and ETS2 antibodies delayed the wound closure time at higest concentration (10 µg/ml) compared to control. Further, our results also showed increased mRNA expression of cdk10 and ETS2 at active phase of migration at approximately 2 fold. Collectively, our data reveals that cdk10 and ETS2 efficiently involved during corneal wound healing. Further studies are warranted to better understand the mechanism and safety of topical cdk10 and ETS2 proteins in corneal epithelial wound-healing and its potential role for human disease treatment. Corneal epithelial injuries and burns produce extensive damage to the ocular surface epithelium and may cause significant loss of function 1. A rapid and efficient healing from injuries and environmental damges is necessary to maintain the cornea barrier that is essential for appropriate vision 2. Delayed in corneal epithelial wounds healing occur in number of disease states, however, persistence of these wounds can lead to loss of vision and even perforation of the eye 3. The World Health Organization (WHO) was estimatated 710 corneal ulcers per 100 000 population every year in south east asia region 4. However, in Pakistan corneal injuries or trauma are the common cause of blindness after cataract but data available about injuries is limited and does not indicate the magnitude of the problem. Recently Baig R et al. reported 39.7% eye injuries among all ocular complaints at emergency department (ED) visits in a private tertiary care hospital Karachi Pakistan 5. In our region, it was also reported that the frequency of trauma was 66% while metallic particles and road accedents were the major cause of ocular injuries 6,7. To reduce the potential of these debilitating injury or wounds is to promote the epithelial migration and decrease the chances of ocular infection with limited toxicity. Treatments for non-healing corneal wounds are limited and no specific therapy available so far. Knowing proper cell cycle division mechanism and specifically with their regulators would thus help to development a new therapeutic tools which trigger or control cell migration and proliferation. A fundamental requirement for proper proliferating and migration of cell, is the
Biological modulation of corneal epithelial wound healing
Arquivos Brasileiros de Oftalmologia
The transparency and maintenance of corneal epithelial integrity are essential for its optical properties and, to preserve these characteristics, the epithelium undergoes continuous renewal. This renewal depends on the control of cell proliferation and differentiation mediated by mitogenic factors responsible for increasing mitoses and stimulating cellular migration. Cell-cell communication plays a pivotal role in epithelial healing process, and several cytokines and growth factors are involved in this process. Understanding the cross-talk and paracrine effects of these cytokines and growth factors released can help in the search for new therapeutic strategies to treat ocular surface diseases.
Control of cellular proliferation in the bovine cornea: An in vitro study
Eye, 1989
Keratocytes from the bovine cornea secrete a factor(s) that stimulates the prolifera tion of corneal epithelial cells. The novel finding of this study is that this stimulation was only achieved if the epithelial cells were already proliferating. Cells which had stopped growing could not be stimulated to re-enter the growth cycle. This stimu lation was not reciprocal; the growth of keratocytes was not stimulated by factor(s) secreted by the epithelium, whereas epithelial factors were able to stimulate the proliferation of thermocytes. The importance of these non-reciprocal growth responses to corneal wound heal ing and immune response is discussed.
Coordinated activation of corneal wound response genes in vivo as observed by in situ hybridization
Experimental Eye Research, 1995
We used subtractive screening of a cDNA library prepared from corneoscleral rims after cauterizing rat corneas. We identified 76 clones whose corresponding mR.NA increased during the wound healing process in an in vivo model of injury which damages the corneal epithelium, stroma, and endothelium. Of these clones, 31 sequences encode known proteins. Another 45 clones are novel sequences based on comparison with the GenBank/EMBL databases. Changes in the level of expression of the novel genes, and a selected number of the known genes, were examined by in situ hybridization 22 and 72 hr after corneal injury. The majority produced a 'wound pattern' of expression such that the mKNAs were highly induced in all cell types adjacent to the wound site at 22 hr post injury. This signal decreased in intensity with distance from the wound site. In a subset of corneoscleral rims examined by in situ hybridization, the mRNAs for these genes were also highly induced in the limbal epithelium, where the progenitor corneal epithelial stem cells reside. By 72 hr, when acute tissue damage had been repaired, the induced mRNA was only faintly present in the thickened epithelium. Our results provide a useful framework for further studies defining the pathophysiological roles of the known and novel proteins encoded by the isolated cDNA clones.
Corneal epithelial wound healing
British Journal of Ophthalmology, 1994
property is dependent in part on the ability of the corneal epithelium to undergo continuous renewal. Epithelial renewal is essential because it enables this tissue to act as a barrier that protects the corneal interior from becoming infected by noxious environmental agents. Furthermore, the smooth optical properties of the corneal epithelial surface are sustained through this renewal process. The rate of renewal is dependent on a highly integrated balance between the processes of corneal epithelial proliferation, differentiation, and cell death. One experimental approach to characterize these three aspects of the renewal process has been to study the kinetics and dynamics of corneal re-epithelialization in a wound-healing model. This effort has employed in vivo and in vitro studies. From such studies it is evident that the appropriate integration and coordination of corneal epithelial proliferation, adhesion, migration, and cell demise is dependent on the actions of a myriad of cytokines. Our goal here is to provide an overview into how these mediators and environmental factors elicit control of cellular proliferation, adhesion, migration, and apoptosis. To this end we review the pertinent literature dealing with the receptor and the cell signaling events that are responsible for mediating cytokine control of corneal epithelial renewal. It is our hope that a better appreciation can be obtained about the complexity of the control processes that are responsible for assuring continuous corneal epithelial renewal in health and disease.
Early and late calcium waves during wound healing in corneal endothelial cells
Wound Repair and Regeneration, 2012
Immediately after wounding, bovine corneal endothelial cells develop a fast calcium wave that propagates from the wound border to the rest of the monolayer and extinguishes in approximately 5 minutes. One hour after wounding, a late, slow calcium wave (SCW) develops concomitantly to the depolarization of the plasma membrane potential of the border cells. The incorporation of inhibitors of the epithelial sodium channel and of the sodium-calcium exchanger produces inhibition of the membrane depolarization and the SCW, and diminishes the rate of wound healing. The L-type calcium channel blocker nimodipine does not have any effect on the SCW. The reversible inhibition of the fast calcium wave does not affect the SCW and only slightly decreases the velocity of healing. Our results suggest that the SCW is at least partially produced by the coupling of the epithelial sodium channel and the sodium-calcium exchanger functioning in reverse mode. They also suggest that the SCW may play a role in the overall healing process.
Impaired cornea wound healing in a tenascin C-deficient mouse model
Laboratory Investigation, 2013
We investigated the effects of loss of tenascin C on the healing of the stroma using incision-injured mice corneas. Tenascin C was upregulated in the stroma following incision injury to the cornea. Wild-type (WT) and tenascin C-null (knockout (KO)) mice on a C57BL/6 background were used. Cell culture experiments were also conducted to determine the effects of the lack of tenascin C on fibrogenic gene expression in ocular fibroblasts. Histology, immunohistochemistry and real-time reverse transcription PCR were employed to evaluate the healing process in the stroma. The difference in the incidence of wound closure was statistically analyzed in hematoxylin and eosin-stained samples between WT and KO mice in addition to qualitative observation. Healing of incision injury in corneal stroma was delayed, with less appearance of myofibroblasts, less invasion of macrophages and reduction in expression of collagen Ia1, fibronectin and transforming growth factor b1 (TGFb1) in KO mice compared with WT mice. In vitro experiments showed that the loss of tenascin C counteracted TGFb1 acceleration of mRNA expression of TGFb1, and of collagen Ia1 and of myofibroblast conversion in ocular fibroblasts. These results indicate that tenascin C modulates wound healing-related fibrogenic gene expression in ocular fibroblasts and is required for primary healing of the corneal stroma.