tretinoin and Corneal-Injuries

We have developed inorganically-coated all-trans retinoic acid (atRA) nanoparticles, nano-sized egg-like particles of atRA (NANOEGG®-atRA). The purpose of this study was to determine the effects of NANOEGG®-atRA on corneal wound healing in vivo and in vitro.. A rabbit corneal epithelial wound healing model was exposed to different concentrations of NANOEGG®-atRA. Wound healing was serially quantified as the ratio of fluorescein-stained area at the selected times to that at baseline. After wound closure, the barrier function of the cornea was determined using low concentrations of tropicamide. At the completion of the experiments, the corneal epithelium was histologically examined. For the in vitro studies, linear scratch wounds were made on cultured SV40-immortalized human corneal epithelial cells (HCE-T). Then, the cells were exposed to different concentrations of NANOEGG®-atRA, and wound healing was determined by the degree of closure of the scratch wound. In addition, the effects of NANOEGG®-atRA on the proliferation of HCE-T cells were determined by WST-8 assays.. Exposure to NANOEGG®-atRA decreased the injured area 24 hrs after the ablation. The maximum effect of NANOEGG®-atRA was observed at a concentration of 33 mM. Histologically, no abnormal or differentiated corneal epithelial cells were observed in the histological sections treated with NANOEGG®-atRA. The tropicamide-induced pupillary dilation was significantly slowed in the eyes treated with NANOEGG®-atRA. NANOEGG®-atRA at concentrations of 3.3 and 33 nM induced earlier wound closure in vitro, but did not induce proliferation of HCE-T cells.. NANOEGG®-atRA promotes wound healing and should be considered for the treatment of wounds of the corneal epithelium.

Topics: Animals; Biological Transport; Cell Movement; Cell Proliferation; Cells, Cultured; Cornea; Corneal Injuries; Disease Models, Animal; Drug Carriers; Epithelium, Corneal; Fluorophotometry; Keratolytic Agents; Male; Membrane Proteins; Nanoparticles; Occludin; Phosphoproteins; Rabbits; Tretinoin; Wound Healing; Zonula Occludens-1 Protein

The aim of the study was to investigate the possible healing effect of the vitamin A analogue all-trans retinoic acid 0.05% (RA) in vaseline on epithelial corneal abrasions in 13 ocularly healthy Copenhagen white rabbits.. A corneal abrasion with a diameter of 6 mm was created centrally in both eyes with a trephine and subsequent rubbing off of the corneal epithelium with an n-heptanol soaked swab The corneal abrasions were treated twice daily with topical applications (50 microl); RA was placed in the right inferior fornix and its vaseline vehicle in the left inferior fornix. Photographic documentation of fluorescein stained, non-healed areas, was performed at time points 0, 12, 24, 36, 48 and 72 h. The rabbits were sacrificed by an overdose of pentobarbital and enucleated. Planimetry was performed from corneal photographs.. Healed epithelial mean area at time point 36 h was significantly higher after RA compared to vehicle (p=0.036, paired t-test). Median time to 75% and 85% healing was significantly shorter for RA compared to vehicle (p= 0.03 and 0.02, log rank-test). No morphological difference, evaluated by light microscopy (hematoxylin-eosin) or scanning electron microscopy, was noted between the two treatments.. It is concluded that RA 0.05% applied twice daily increases the healing rate compared to vaseline vehicle.

Topics: Administration, Topical; Animals; Cornea; Corneal Injuries; Eye Injuries; Female; Fluorophotometry; Keratolytic Agents; Microscopy, Electron, Scanning; Ophthalmic Solutions; Rabbits; Tretinoin; Wound Healing; Wounds, Nonpenetrating

In previous studies of topical application of retinoic acid to the eye, retinoic acid in an oil vehicle has been used. An all-trans-retinoic acid (Tretinoin, USP) formulation in a petrolatum-based ophthalmic ointment vehicle has now been developed which is chemically stable for at least one year. The ointment is effective at retinoic acid concentrations of 0.01-0.1% in reversing corneal keratinization in vitamin A-deficient, xerophthalmic rabbits. At 0.1% it also stimulates the healing rate of corneal epithelial wounds in rabbits and monkeys. Retinoic acid ointment may prove to be valuable clinically in the treatment of xerophthalmia, corneal epithelial erosions, and related ocular surface abnormalities.

Topics: Animals; Corneal Injuries; Drug Stability; Epithelium; Macaca fascicularis; Ointments; Rabbits; Tretinoin; Wound Healing; Wounds, Penetrating; Xerophthalmia

We treated experimental corneal epithelial wounds in rabbits with topical retinoids. Treatment with 0.1% all-trans-retinoic acid three times per day resulted in a 21% increase in the healing rate compared to the control eyes. Treatment five times a day resulted in a 35% increase in healing rate. Treatment with topical retinoic acid also promoted corneal deturgescence. Retinyl palmitate, retinyl acetate, retinol, and 13-cis-retinoic acid had no effect on corneal wound healing. These data suggested that topically applied all-trans-retinoic acid may be effective in promoting corneal healing after surgery and in the treatment of persistent and recurring corneal epithelial defects.

Topics: Administration, Topical; Animals; Cornea; Corneal Injuries; Diterpenes; Rabbits; Retinyl Esters; Tretinoin; Vitamin A; Wound Healing

The entire corneal epithelium of each of 16 rabbits was removed bilaterally. Tretinoin (vitamin A acid) ointment was applied topically twice daily to the eyes of one half of the experimental animals, and the ointment base alone was applied to the eyes of the other half (the controls). On days 1, 2, and 3 after the removal of the epithelium, the healing of the denuded corneas of the animals receiving tretinoin was significantly (P = .01, .01, and .05, respectively) more advanced than the healing of the corneas of the control animals.

Topics: Administration, Topical; Animals; Cornea; Corneal Injuries; Epithelium; Female; Male; Rabbits; Tretinoin; Vitamin A; Wound Healing