Application Of Eye Drops Research Articles

Effect of 5-S-GAD on UV-B-induced cataracts in rats

5-S-Glutathionyl-N-beta-alanyl-3,4-dihydroxyphenylalanine (5-S-GAD) is a novel antibacterial substance purified from Sarcophaga peregrina (flesh fly) that has both a radical scavenging activity and antioxidative activity. This is a report of an investigation of the effect of 5-S-GAD (eyedrops) on UVB-induced cataracts in rats. Brown Norway male rats (n = 32; 7 weeks old) were treated with either 5-S-GAD 0.1%, 5-SGAD 1%, astaxanthin (AST) 0.1% suspension eyedrops or the vehicle alone (the solution without 5-S-GAD) three times a day (three doses at 5-min intervals each time). The treatment was scheduled 2 days before UV-B exposure and 2 days after UV-B exposure. Exposure to 100-200 mJ/cm(2) UV-B was performed once a week between drug treatments for 9 consecutive weeks, with a total dose of 1200 mJ/cm(2) UV-B. Ocular penetration of 5-S-GAD was analyzed using high-pressure liquid chromatography (HPLC). Cataract formation was documented by an anterior eye segment analysis system once a week under mydriasis. The light-scattering intensity (LSI) of the anterior superficial cortex region was measured. In the eighth to ninth week after the start of UV-B exposure, the LSI of anterior subcapsular lenses of 5-S-GAD-treated groups, as detected by HPLC, was significantly lower (P < 0.05) than that of the control, whereas no such difference was found in the AST-treated group. 5-S-GAD eyedrop application may delay the progression of UV-B-induced cataract in rats.

Effect of Dosage and Vaccination Route on Transmission of a Live Attenuated Mycoplasma gallisepticum Vaccine: A Broiler Model

Mycoplasma gallisepticum (MG) is an economically significant pathogen of poultry species. Among the table egg sector of the poultry industry, live attenuated strains of MG are commonly used to limit production losses associated with MG-induced disease. These vaccines, however, may be problematic to broiler- and turkey-related industries because of associated virulence; therefore, an understanding of the transmissibility of the live MG vaccines is of particular importance. In the present study, a broiler model addresses the effect of vaccine application route and dosage on the transmission of the MG vaccine FVAX-MG to commingled unvaccinated subjects for 7 wk postvaccination. Vaccinations occurred at 2 wk of age via eyedrop or spray application at 1 x (4 x 10(6) colony-forming units [cfu]), 10(-3) x (4 x 10(3) cfu), or 10(-6) x (4 cfu) of the manufacturer's recommended dosage, and subsequent transmission to unvaccinated subjects was measured. The serologic response to MG antigen and the presence of MG DNA indicated FVAX-MG transmission only within the 1 x FVAX-MG eyedrop treatment. Among no other treatment was transmission of FVAX-MG detected. The results of the present study demonstrate that the dosage and vaccination route may have direct implications on subsequent transmission of FVAX-MG.

Advances in treatment for neurotrophic keratopathy

To review the clinical characteristics and possible new mode of treatments for the corneal epithelial disorders associated with neurotrophic keratopathy. The successful clinical applications of eyedrops containing substance P and insulin-like growth factor-1, or peptides derived therefrom, were reported for the treatment of humans with neurotrophic keratopathy. Neurotrophic keratopathy, a degenerative disease of the cornea, is caused by an impairment of function of the trigeminal nerve and an insufficient supply of neural factors. The combination of substance P, a sensory neurotransmitter, and insulin-like growth factor-1 induced a synergistic stimulatory effect on corneal epithelial migration as well as on corneal wound closure in vivo. We discuss the roles of growth factors and substance P, a sensory neurotransmitter released from the trigeminal nerve, in corneal epithelial wound healing as well as the clinical application of these molecules to the treatment of neurotrophic keratopathy.

Bevacizumab Application Delays Epithelial Healing in Rabbit Cornea

Vascular endothelial growth factor (VEGF) is essential for neovascularization, but the use of anti-VEGF therapies to inhibit neovascularization may influence epithelial wound healing. Here, the effects of bevacizumab on corneal epithelial wound healing time in rabbit models, cell proliferation, and expression of integrins in human corneal epithelial and fibroblast cells were evaluated. To compare epithelial wound healing times, epithelial defect sizes were measured after application of bevacizumab topical eye drops at 0, 0.5, 1.0, 1.5, 2.5, or 5 mg/mL, twice daily, to mechanically debrided epithelia of rabbit corneas. The cellular covering of wounded areas and expression of Ki67 were assessed after scrape injuries in cultures of human corneal epithelial and fibroblast cells. Expression of cell surface integrins and collagens was measured using plates coated with mouse monoclonal antibodies against human adhesion molecules, and relevant mRNA levels were assessed by reverse-transcription-polymerase chain reaction (RT-PCR). The application of bevacizumab topical eye drops at 1.0, 1.5, 2.5, or 5 mg/mL delayed rabbit corneal epithelial healing. Cell cultures growing under high concentrations of bevacizumab showed delay in the proliferation of corneal epithelial and fibroblast cells. Surface expression of mRNA encoding integrins and collagens were decreased by 1.5 mg/mL of bevacizumab. Bevacizumab delayed corneal epithelial wound healing and inhibited integrin expression. When bevacizumab is used to reduce the development of new corneal vessels, slight delays in epithelial wound healing are possible and cellular proliferation is to be expected.

Effects of mutant kringle 5 eye drops on the survival time of corneal allografts in rat

To investigate the preventative effect of mutant kringle 5 (mK5) eye drops on corneal allograft rejection. It was a experimental study. The outbred strain F344 and Lewis rats were used as donors and recipients respectively. Sixty Lewis rats were randomly divided into B, C, D and E Group; Group A, F344 rats autograft control; Group B, allograft control (the control groups were given normal sodium only); Group C and D, allograft groups, were treated with 5 mg/L and 10 mg/L mK5 eye drops respectively; Group E, allograft group, was treated with 0.1% dexamethasone eye drops. The eye drops were applied one drop four times per day for two weeks, the occurrence and development of corneal allograft rejection and corneal neovascularization (CNV) was observed every other day by slit-lamp microscope, the grafts were evaluated clinically by means of Holland's scoring system and the area of CNV was calculated. Nine rats per group were killed on the 14th day, and the corneas were taken for histopathological examinations. Analysis of variance was used to analyze the outcomes. The average graft survival time of Group B, C, D and E was (9.3 +/- 2.1), (21.1 +/- 7.3), (23.5 +/- 10.8) and (28.2 +/- 19.1) d respectively, Compared with Group B, Group C and D had a statistically significant prolongation of survival time (q = 10.24, 13.47; P < 0.05). Though treated with 0.1% dexamethasone eye drops (Group E) prolonged transplant survival time as compared with mK5 eye drops, but the difference was not statistically significant (q = 2.54, 1.49; P > 0.05). The occurrence of CNV in Group A was (3.1 +/- 0.8) d, Group B (2.6 +/- 0.5) d, Group C (6.4 +/- 0.5) d, Group D (7.8 +/- 0.7) d and Group E (5.3 +/- 1.0) d. Significant difference (q = 31.58, 51.21, 19.98; P < 0.05) was found between groups C, D, E and Group A. There were also significant difference between groups C, D, E and Group B (q = 43.87, 67.14, 24.53; P < 0.05). The CNV areas of Group C and Group D were also smaller than Group B (q = 30.76, 62.14; P < 0.05). The results was similar compared with Group E (q = 15.20, 25.64; P < 0.05). Fewer inflammatory cells and CNV were found in the cornea of the groups treated with mK5 eye drops. Topical application of mK5 eye drops can prevent corneal graft rejection and corneal neovascularization in rats.

The potential therapeutic of siRNA eye drops in ocular diseases

In recent years, researchers have expressed an ongoing interest in developing RNA interference (RNAi) technology for therapeutic gene suppression in various diseases. Preclinical studies in animal models and cultured cell studies indicated that RNAi technology was an effective experimental tool against a variety of ocular diseases, and some small interference RNA (siRNA) drugs have been entered into clinical trials in Stage I and Stage II. However, in these studies siRNAs were delivered into ocular tissues via either systemic or subconjunctival/intravitreous injection, which is invasive and harmful if repeated. Based on this evidence, we hypothesize that topical application of siRNA eye drops may be a safe and effective therapeutic option in ocular surface diseases with temporary changes of gene expression. Furthermore, siRNA eye drops targeting different genes may simultaneously treat several ocular surface diseases.

Ação do colírio de fenilefrina 10% no posicionamento palpebral de indivíduos normais

To determine the upper and lower eyelid position with a single drop of 10% phenylephrine in normal individuals and observe positional lid changes in upper and lower lids of the opposite eye. Prospective observational study including 24 healthy subjects of both genders (age range: 20-39 yrs) submitted to instillation of a single drop of 10% phenylephrine in the upper fornix of one randomly chosen eye. A video camera recorded the images of both eyes before and after eye drop application at 3, 10, 15, 30, 45 and 60 minutes. The images were digitally processed and edited to analyze lid measurements (upper lid height: distance between the highest upper margin lid point and a horizontal line traced from the medial to the lateral canthus; lower lid height: distance between the lowest margin lid point and the above-mentioned line). Before and after drug instillation, upper lid height was significantly different (p<0.001) at all moments with a mean elevation of 0.79 mm. The lower lid height changed too with a mean retraction of 0.37 mm. In the fellow eye upper lid drop was observed at almost all moments with the lowest value at 3 minutes (mean reduction of 0.68 mm) and elevation (0.37 mm) of lower lid. This experiment showed that a single drop of 10% phenylephrine acted not only on the upper eyelid but also on lower lid of the tested eye. Control mechanism of lid opening and closing changed upper and lower lid positioning of the opposite eye in healthy subjects.

Electronic compliance monitoring in glaucoma patients used to topical therapy

Abstract Purpose Individual compliance of glaucoma and ocular hypertensive patients with Brimonidine was studied with regards to total dose, dosage intervals, coverage, drug waste, attempts per application and risk factors for low compliance. Methods Thirty‐eight men and 26women aged 70 ±11 years [42‐89] received conventional Brimonidine vials (Alphagan®, Allergan™) equipped with a microprocessor‐controlled monitoring device capable to record date and time of each eye drop application with a known detection sensitivity for eye drop applications ~ 99%. 48 glaucoma and 16 ocular hypertensive patients used to eye drop therapy for 11 ±8 years [1‐35] were enrolled and randomly assigned to Brimonidine therapy b.i.d or t.i.d daily for 4 weeks. Results Electronic records revealed a mean of 1.4 applications per day (range: 0.7‐2.2) for patients assigned to Brimonidine 2x daily with a mean treatment interval of 18.2 hours (range: 11.2‐38.4 h). Patients on Brimonidine 3x daily showed a mean rate of 1.8 applications per day (range: 1.0‐2.7) and a mean treatment interval of 12.4 h (range: 9.1‐39.7 h). 10 patients ceased therapy before completing the 4 weeks period, therein 4 with side effects and 6 patients having emptied the bottle prematurely. Conclusion Almost 10 percent of the patients emptied their vial in less than 4 weeks by using more than one drop per application and thereby do need refills more often than usually calculated. Our data confirm the need for larger studies on individual compliance with topical ocular therapy in glaucoma. Electronic compliance monitoring may be a useful tool in ophthalmic practice to recognize low‐compliant patients.

Persisting Corneal Erosion Under Cetuximab (Erbitux) Treatment (Epidermal Growth Factor Receptor Antibody)

To report persisting corneal erosion and trichomegaly as ocular side effects of cetuximab (Erbitux) treatment, a monoclonal antibody against the epidermal growth factor (EGF) receptor. A 62-year-old patient was treated with combined chemotherapy including cetuximab for colorectal carcinoma and showed accelerated growth of eyelashes with persistent bilateral corneal erosions resistant to conservative treatment. Topical EGF was successfully applied as an experimental treatment to antagonize the inhibitory effect of the EGF receptor antibody. Topical application of EGF led to rapid improvement, with complete healing of the epithelial defect after 7 (left eye) and 19 days (right eye) while application of cetuximab was continued. Cetuximab (Erbitux) can cause impairment of corneal wound healing as an ocular side effect. Patients concerned may benefit from application of EGF eyedrops.

Breakdown Evaluation of Corneal Epithelial Barrier Caused by Antiallergic Eyedrops Using an Electrophysiologic Method

The aim of this study was to examine the usefulness of an electrophysiologic method for predicting corneal epithelial breakdown by antiallergic eyedrops and comparing the results with those in other appraisal methods. Six kinds of antiallergic eyedrops, including benzalkonium chloride (BK) as an ophthalmic preservative and two kinds of BK-free antiallergic eyedrops, were used in this study. Eyedrops were applied to excise rabbit corneas and monitoring was performed according to an electrophysiologic method, using a commercially available chamber system to mimic human tear turnover. Changes in transepithelial electrical resistance (TEER) in the corneal surface were recorded. The cytotoxicity of each kind of eyedrops in a normal rabbit corneal epithelial (NRCE) cell line and a human endothelial cell line EA.hy926 was also examined. The extent of decrease in the corneal TEER after applying antiallergic eyedrops was dependent on the concentration of the BK included as a preservative, but it was also affected by the different kinds of drugs when the BK concentration was low. Higher cytotoxicity of the eyedrops against the NRCE and EA.hy926 cell lines was observed with a reduction of TEER. Monitoring changes in the corneal TEER, according to the electrophysiologic method with the application of antiallergic eyedrops, is useful for predicting corneal epithelial breakdown caused by their instillation.

Patientenzufriedenheit nach filtrierender Glaukomchirurgie mit Mitomycin C

There are few published data on patient satisfaction following glaucoma surgery. The aim of our study was to investigate factors influencing patient satisfaction more than one year after trabeculectomy with mitomycin C. We sent a two-page questionnaire to 61 female glaucoma patients who had consecutively undergone filtering surgery with MMC at the Department of Ophthalmology, University of Cologne, requesting anonymous replies (mean follow-up 19.2+/-2.5 months). The response rate was 79%. There was no significant inverse correlation between patient satisfaction and recent IOP values, redness of the eye, local irritation or foreign body sensation. There was a significant correlation between patient satisfaction and visual function, a significant inverse correlation between frequency of visits to the ophthalmologist and frequency of eye drop application. A weak, insignificant inverse correlation was found between satisfaction and number of topical medications. Patient satisfaction seems to correlate primarily with practical impact on everyday life, visual function, frequency of eye drop application and visits to the eye doctor being identified as the major issues. Local symptoms related to the filtering bleb seem to have a minor influence on patient satisfaction.

Calcinosis conjunctivae bei chronischer Blepharitis

We present a case of a 53-year-old female patient with chronic blepharitis and conjunctival overgrowth of the cornea. Histologically the conjunctival overgrowth contained foreign body granulomas around calcification focuses. This could have been promoted by the application of phosphate-containing eye drops and the presence of chemokines like TNF-alpha, which occur in chronic blepharitis. Thus, we recommend the application of phosphate-free eye drops in patients with chronic blepharitis.

Application of Umbilical Cord Serum Eyedrops for the Treatment of Neurotrophic Keratitis

Application of Umbilical Cord Serum Eyedrops for the Treatment of Neurotrophic Keratitis

Plasminogen deficiency.

Plasminogen (plg) deficiency has been classified as (i) hypoplasminogenemia or 'true' type I plg deficiency, and (ii) dysplasminogenemia, also called type II plg deficiency. Both forms, severe hypoplasminogenemia and dysplasminogenemia, are not causally linked to venous thrombosis. Dysplasminogenemia does not lead to a specific clinical manifestation and probably represents only a polymorphic variation in the general population, mainly in Asian countries. Severe hypoplasminogenemia is associated with compromised extracellular fibrin clearance during wound healing, leading to pseudomembraneous (ligneous) lesions on affected mucous membranes (eye, middle ear, mouth, pharynx, duodenum, upper and lower respiratory tract and female genital tract). Ligneous conjunctivitis is by far the most common clinical manifestation. More than 12% of patients with severe hypoplasminogenemia exhibit congenital occlusive hydrocephalus. In milder cases of ligneous conjunctivitis, topical application of plg-containing eye drops, fresh frozen plasma, heparin, corticosteroids or certain immunosuppressive agents (such as azathioprine) may be more or less effective. Oral treatment with sex hormones was successful in two female patients with ligneous conjunctivitis. In severe cases with possibly life-threatening multi-organ involvement, true therapeutic options are not available at present. The plg-knockout mouse is a useful tool to study the many different properties of plg in a variety of settings, such as wound healing, tissue repair and tissue remodeling, virulence and invasiveness of certain bacteria in the human host, tumor growth and dissemination, as well as arteriosclerosis.

Long-term, topical insulin administration increases the severity of retinal vascular pathology in streptozotocin-induced diabetic rats

Background We previously reported that insulin accumulated in the retina of diabetic rats after topical insulin eye drop treatment. In light of insulin’s reported benefits to the retina, we hypothesized that the delivery of insulin to the retina by eye drop application might be efficacious in preventing diabetic retinopathy. Methods We applied daily, uni-ocular porcine insulin drops (0.75%) to diabetic rats for 14 months and then analyzed their retinas for vascular pathology. Results Our data showed that high-dose insulin eye drop treatment increased the number of retinal acellular capillaries, with many of these capillaries exhibiting a degenerated, threadlike appearance. The retinas also showed extensive capillary obliteration and had tangled masses of vascular cells. The glycated hemoglobin levels of eye drop–treated rats were similar to those found in control, vehicle-treated diabetic animals at sacrifice. Retinal insulin levels remained elevated after a 2-week regimen of daily insulin eye drops, suggesting that our treatment protocol resulted in the pooling of insulin in the retina. A similar treatment regimen was also found to have no effect on retinal glucose concentration. Conclusion Our results showed that treatment of diabetic rats with daily, high-dose insulin eye drops intensified their retinal pathology.

Determination of Ketorolac Tromethamine in Human Eye Samples by HPLC with Photo Diode-Array Detection

A sensitive and selective reversed-phase HPLC method for analysis of ketorolac in aqueous and vitreous humor from the human eye has been developed and validated. Chromatographic separation was achieved on a 250 mm × 4.6 mm i.d., 5-μm particle, C18 analytical column. Photo diode-array detection was performed at 314 nm. Response was a linear function of ketorolac concentration from 10 to 800 ng mL−1. The limits of detection (LOD) and quantification (LOQ) were 3.0 and 10 ng mL−1, respectively. Intra-day and inter-day bias were less than 2.05 and 2.28%, respectively, and intra-day and inter-day RSD were no higher than 3.60 and 5.80%, respectively. Fluid obtained from patients eyes’ after topical application of Acular eye drops before retina decolman surgery was analyzed by use of the method. The method enabled successful quantification of levels of ketorolac in aqueous and vitreous humor.

Monitoring individual compliance in glaucoma patients used to topical therapy

Abstract Purpose: Individual compliance with Brimonidine eye drops was studied in glaucoma patients and ocular hypertensives. Methods: Conventional Brimonidine vials were equipped with a microprocessor‐controlled monitoring device capable to record date and time of each eye drop application including ambient temperature. After written informed consent, glaucoma and ocular hypertensive patients used to eye drop therapy were randomly assigned to Brimonidine therapy b.i.d or t.i.d daily for 4 weeks. Results: Twenty six males and fourteen females aged 69 ± 11 years [42‐89] were enrolled in this study. According to the monitoring devices all patients were non‐compliant with regard to total dose and coverage. Electronic records revealed a mean of 1.5 (range: 1.1‐2.0) applications per day for patients assigned to Brimonidine 2x daily with a mean treatment interval of 16.8 hours (range: 12.1‐22.2 h). Patients on Brimonidine 3x daily showed a mean rate of 1.9 (range: 1.8‐2.7) applications per day and a mean treatment interval of 11.9 h (range: 9.1‐13.9 h). One patient discontinued therapy after day 7 (12 applications) and one after day 1 (1 application only). No difference was observed between IOP at baseline and after one month (p=0.16). Conclusions: The monitoring devices permit to detect individual non‐compliance with regard to missed doses, non‐treatment intervals. Our data confirm the need for larger studies on individual compliance with topical ocular therapy in glaucoma.

Autologous Serum Eyedrops in the Treatment of Aniridic Keratopathy

To study the effect of autologous serum eyedrop application in aniridic keratopathy. Prospective, consecutive, comparative, interventional case series. Twenty-six eyes from 13 patients (7 males and 6 females) with aniridic keratopathy treated with autologous serum eyedrops. All patients underwent a complete ophthalmic examination. The ocular surface examinations included corneal impression cytologic analysis and tear film evaluation. The eyes were divided into 4 groups according to the Mackman classification. Ocular surface photography was used to evaluate the corneal surface and tear film before treatment and every 2 or 3 days until serum drops were stopped. Tear films were evaluated by tear film break-up time (BUT) (normal, 10 seconds or more), Schirmer's test with anesthesia (normal, 10 mm/5 minutes or more), tear meniscus level (normal, 0.5 mm or more), and rose bengal and fluorescein staining pattern of the cornea. Impression cytologic analysis was carried out both before starting the serum eyedrops treatment and a few days after its finalization. Tear film production and stability, corneal epithelialization, and corneal epithelium squamous metaplasia. There were no local side effects from autologous serum treatment. Clinical manifestations and slit-lamp findings were in relation to the severity of keratopathy. All patients showed a subjective improvement of keratopathy symptoms after the autologous serum applications. The corneal epithelialization, corneal epithelial cell squamous metaplasia, and tear stability improved significantly with the treatment, but visual acuity, regression of vascular pannus, and subepithelial scarring showed only slight improvement with treatment. Autologous serum eyedrops improved the aniridic keratopathy in all patients, particularly in patients with light or moderate severity. In these patients, use of autologous serum eyedrops was superior to conventional therapy with substitute tears for improving the ocular surface and subjective comfort.

Application of Umbilical Cord Serum Eyedrops for the Treatment of Neurotrophic Keratitis

To investigate the efficacy of umbilical cord serum eyedrops for the treatment of neurotrophic keratitis. Prospective noncomparative case series. Twenty-eight eyes of 28 patients with neurotrophic keratitis who were refractory to conventional treatment. The patients with neurotrophic keraitis were treated with 20% umbilical cord serum eyedrops 6 to 10 times a day. Ophthalmic examinations including best-corrected visual acuity (VA) measurement, corneal sensitivity test, corneal fluorescein staining, and anterior segment photography were performed before and after the treatment. Concentrations of substance P, insulinlike growth factor 1 (IGF-1), and nerve growth factor (NGF) in umbilical cord serum, normal peripheral blood serum, and tears were measured. Epithelial healing time; changes of VA and corneal sensitivity after treatment; and levels of substance P, IGF-1, and NGF in umbilical cord serum, normal peripheral blood serum, and tears. The epithelial defect healed completely in all eyes, with a mean healing time of 4.4+/-4.0 weeks. The epithelial defect healed within 2 weeks in 8 eyes (28.6%), between 2 and 4 weeks in 14 eyes (50.0%), and after 4 weeks in 6 eyes (21.4%). After treatment, VA improved by >2 lines in 17 eyes (60.7%). Mean pretreatment corneal sensitivity was 21.1+/-10.5 mm, and mean posttreatment corneal sensitivity was 24.3+/-11.7 mm (P<0.01). Mean concentrations of substance P, IGF-1, and NGF were 245.3+/-53.9 pg/ml, 239.0+/-77.1 ng/ml, and 729.7+/-72.0 pg/ml in umbilical cord serum; 169.5+/-81.0 pg/ml, 375.5+/-51.3 ng/ml, and 401.7+/-98.1 pg/ml in peripheral blood serum; and 69.8+/-24.9 pg/ml, 75.7+/-50.5 ng/ml, and 107.5+/-70.9 pg/ml in tears, respectively. Umbilical cord serum contains many neurotrophic factors, and umbilical cord serum eyedrops appeared to be effective for the treatment of neurotrophic keratitis.

Protective Effect of Uridine on Cornea in a Rabbit Dry Eye Model

To investigate the effect of uridine on cultured human corneal epithelial cells and keratocytes in vitro and to evaluate whether the application of uridine-containing eye drops could improve ocular surface health in an in vivo dry eye model. Uridine was added to cultured epithelial cells (3 x 10(4) cells/well) and keratocytes (1 x 10(4) cells/well) at various concentrations (0.5-50 microM). Cytotoxicity was tested with the use of MTT assay, and the cells were assessed for apoptosis with the use of flow cytometry. Expressions of hyaluronic acid (HA), glycosaminoglycan (GAG), nitric oxide (NO), and matrix metalloproteinase (MMP)-9 were measured. In vivo, the degree of reepithelialization was assessed after topical application of uridine (100 microM) in a rabbit corneal wound model. Changes in tear production and conjunctival goblet cell counts were investigated after instillation of various concentrations of uridine-containing eye drops in a rabbit dry eye model. In vitro, uridine showed no cellular toxicity. It increased the biosynthesis of HA and GAG and reduced MMP-9 levels in cultured corneal epithelial cells and keratocytes. In vivo, uridine enhanced corneal wound healing and significantly increased the number of conjunctival goblet cells in rabbits. Uridine can restore the health of the ocular surface in a rabbit corneal wound and dry eye model.