Effects of antiinflammatory drugs on migration of the rabbit corneal epithelium

1-Nitropyrene disrupts testicular steroidogenesis via oxidative stress-evoked PERK-eIF2α pathway

Our previous study showed 1-Nitropyrene (1-NP) exposure disrupted testicular testosterone synthesis in mouse, but the exact mechanism needs further investigation. The present research found 4-phenylbutyric acid (4-PBA), an endoplasmic reticulum (ER) stress inhibitor, recovered 1-NP-induced ER stress and testosterone synthases reduction in TM3 cells. GSK2606414, a protein kinase-like ER kinase (PERK) kinase inhibitor, attenuated 1-NP-induced PERK-eukaryotic translation initiation factor 2α (eIF2α) signaling activation and downregulation of steroidogenic proteins in TM3 cells. Both 4-PBA and GSK2606414 attenuated 1-NP-induced steroidogenesis disruption in TM3 cells. Further studies used N-Acetyl-L-cysteine (NAC) as a classical antioxidant to explore whether oxidative stress-activated ER stress mediated 1-NP-induced testosterone synthases reduction and steroidogenesis disruption in TM3 cells and mouse testes. The results showed NAC pretreatment mitigated oxidative stress, and subsequently attenuated ER stress, particularly PERK-eIF2α signaling activation, and downregulation of testosterone synthases in 1-NP-treated TM3 cells. More importantly, NAC extenuated 1-NP-induced testosterone synthesis in vitro and in vivo. The current work indicated that oxidative stress-caused ER stress, particularly PERK-eIF2α pathway activation, mediates 1-NP-downregulated steroidogenic proteins and steroidogenesis disruption in TM3 cells and mouse testes. Significantly, the current study provides a theoretical basis and demonstrates the experimental evidence for the potential application of antioxidant, such as NAC, in public health prevention, particularly in 1-NP-induced endocrine disorder.

Prophylactic use of nonsteroidal anti-inflammatory drugs after cataract surgery and corneal melt

Purpose:

To describe a case where prophylactic use of nonsteroidal anti-inflammatory drugs (NSAID) eye drops lead to recurrent corneal melt with loss of vision and a brief literature review.

Methods:

This is a case report of an 84-year-old diabetic female with chronic dry eye, operated by two different surgeons on each eye at different time intervals. She received topical NSAID prophylaxis after the second surgery only, which led to blindness due to recurrent corneal melt and chronic choroidal effusions. We also present a brief literature review.

Results:

This lady presented with corneal melt and perforation 5 days following the use of topical NSAIDs prophylaxis after a routine cataract surgery in the second eye. Unfortunately, all efforts to save her vision and eye were unsuccessful as she developed repeated complications in spite of corneal gluing, amniotic membrane, penetrating keratoplasty, and tarsorrhaphy. She also had chronic choroidal effusions. She ended up with an opaque cornea and a subtotal tarsorrhaphy, with no other option to improve her vision as she did not qualify for sedation or general anesthesia due to her poor systemic health.

Conclusion:

Although it is a common practice for diabetic patients to have topical NSAIDs prophylaxis in combination with steroid eye drops to reduce the risk of cystoid macular edema after cataract surgery, the elderly diabetic patients with concomitant dry eyes should be considered high risk for corneal melt and should be closely monitored. This case highlights the rare but serious complication of topical NSAIDs prophylaxis in the vulnerable cornea, which warrants careful consideration.

Bilateral corneal melting associated with topical diclofenac 0.1% after cataract surgery in a patient with Sjögren's syndrome

A 79-year-old female with Sjögren's syndrome (SS) underwent phacoemulsification and lens implantation in both eyes within 2 days. Postoperatively, topical diclofenac 0.1% and tobramycin 0.3% were applied. She presented 10 days later with photophobia, large central corneal melting, and visual acuity of counting finger in both eyes. Diclofenac was discontinued, and systemic doxycycline and steroids were administered. Amniotic membrane transplantation was performed in the left eye with topical steroid and autologous serum 20%. Corneal melting gradually healed in 3 weeks, but the centers of both corneas became thin and opaque. Hyperopic shift and irregular corneal surface were more significant in the right eye than in the left eye. Vision recovered to 0.05 and 0.1 in the right and left eyes, respectively. Topical nonsteroidal anti-inflammatory drugs should be used with caution in cataract surgery in patients with SS.

Update on twice-daily bromfenac sodium sesquihydrate to treat postoperative ocular inflammation following cataract extraction

Ophthalmic bromfenac sodium sesquihydrate is a topically applied selective cyclooxygenase (COX)-2 inhibitor. It is similar to amfenac, except for a bromine atom at the C(4) of the benzoyl ring position, which markedly affects its in vitro and in vivo potency, extends the duration of anti-inflammatory activity, and enhances its inhibitory effect on COX-2 absorption across the cornea and penetration into ocular tissues. The United States Food and Drug Administration approved bromfenac in 2005 for the treatment of postoperative inflammation and the reduction of ocular pain in patients who have undergone cataract surgery. Nonsteroidal anti-inflammatory drugs (NSAIDs), and among them bromfenac, could be even more effective than steroids at reestablishing the blood-aqueous barrier, as revealed by flare on slit-lamp examination and as quantitatively measured using ocular fluorophotometry. Similar to other NSAIDs, it has a role in inhibiting intraoperative miosis during cataract surgery. However, bromfenac also seems to be useful in other situations, such as refractive surgery, allergic conjunctivitis (not useful in dry eye), choroidal neovascularization, and even ocular oncology. No reports of systemic toxicity have been published and bromfenac has good topical tolerance with a low incidence of adverse effects.

Penetrating ocular gunshot injury in a Labrador Retriever

A 3½-year-old, female (spayed) working black Labrador Retriever was referred to the Unit of Comparative Ophthalmology at the Animal Health Trust after a penetrating lead gunshot injury to the right eye. Clinical examination revealed penetrating injuries to the right cornea, left lateral canthus, and left forelimb. Radiography revealed the presence of multiple metallic foreign bodies in the head and one in the left forelimb. B-mode ocular ultrasonography confirmed the presence of an intraocular metallic foreign body within the posterior tunics of the right eye. Medical treatment of the right eye over a period of 1 month resulted in a comfortable, visual eye. Long-term follow-up over 4½ years revealed a slow deterioration in vision because of progressive lens opacification and the presence of a localized area of chorioretinopathy.

Management of ocular inflammation and pain following cataract surgery: focus on bromfenac ophthalmic solution

Recently, several new ophthalmic NSAID products have been introduced for commercial use in the United States. The purpose of this review is to briefly overview the ophthalmic NSAIDs currently in use and to discuss the management of postoperative ocular inflammation and pain following cataract surgery with a particular focus on bromfenac ophthalmic solution 0.09%. Bromfenac ophthalmic solution 0.09% is indicated for the reduction of ocular pain and inflammation following cataract surgery. Studies have shown that bromfenac ophthalmic solution 0.09% has equivalent efficacy to the other topical NSAIDs in reducing postsurgical inflammation and controlling pain. The unique chemical structure of bromfenac makes it both a potent inhibitor of the COX-2 enzyme and a highly lipophilic molecule that rapidly penetrates to produce early and sustained drug levels in all ocular tissues. Clinically, these pharmacokinetic features are manifested in a rapid reduction of postsurgical inflammation and pain with bid dosing. Bromfenac ophthalmic solution 0.09% is a versatile agent and is effective when used as either monotherapy or as an adjunct therapy to steroids.

Corneal melting and perforation in Stevens Johnson syndrome following topical bromfenac use

We report a case of a 20-year-old woman with tear deficiency secondary to Stevens Johnson syndrome who developed bilateral corneal melting following use of bromfenac (Xibrom), a nonsteroidal antiinflammatory drug (NSAID), for 2 weeks. The patient presented with complaints of light sensitivity and pain in the right eye. The slitlamp examination revealed a corneal perforation with iris plug in the right eye and an 85% thinned cornea in the left eye. She was admitted to the hospital, where Xibrom was discontinued, therapeutic contact lenses were placed, and a regimen of topical antibiotic agents was instituted. One day after admission, penetrating keratoplasty was performed in the right eye, an amniotic membrane was placed in the left eye, and tarsorrhaphy was performed bilaterally. The clinical features of this case highlight the importance of being selective when administering NSAIDs in patients with a compromised ocular surface.

Cyclooxygenase 2 expression in rat corneas after ethanol exposure

PURPOSE

To evaluate the effects of ethanol exposure of the cornea on inflammation in corneal epithelium.

SETTING

Department of Ophthalmology, Wakayama Medical University, Wakayama, Japan.

METHODS

One cornea of Wistar rats (n = 60) was exposed to ethanol 20% for 30 seconds. The animals were killed 0.5, 1.0, 1.5, 2.0, 6.0, 12.0, 24.0, 48.0, or 72.0 hours or 7 days after treatment. The paraffin section or cryosection of the treated eyes was processed for histology; immunohistochemistry for cyclooxygenase 2 (COX2); p65 subunit of nuclear factor kappa B (NF-kappaB), which is the major transcription factor involved in COX2 expression; phospho-IkappaB; or in situ hybridization for COX2 mRNA.

RESULTS

In the uninjured corneas, faint immunoreactivity for COX2 was detected in the basal cells of the corneal epithelium, but not in other cell layers. Cyclooxygenase 2 mRNA was not observed in the injured epithelium; it was expressed 2 hours after ethanol exposure, but not 3 hours or later after treatment. The COX2 protein was detected in the corneal epithelium throughout the epithelial layers from 3 to 72 hours, but not at 7 days. The p65 of NF-kappaB translocated to the nuclei of corneal epithelium 3 to 24 hours after treatment but was not seen in the nuclei 48 hours after treatment. Phospho-I kappaB was detected in corneal epithelium 6 hours after treatment, but not 12 hours or later.

CONCLUSION

Ethanol exposure activated NF-kappaB and upregulated COX2 expression, which may cause inflammation in corneal tissue.

Evaluation of a new preoperative ophthalmic solution

BACKGROUND

Maximum mydriasis and corneal clarity during intraocular surgery are important to ensure operational safety. However, repeated instillation of mydriatic and anti-inflammatory ophthalmic solutions during surgery may affect compliance and may damage the corneal epithelium. We developed an ophthalmic solution containing tropicamide, phenylephrine hydrochloride and diclofenac sodium, and compared the properties and effect on corneal epithelial barrier function and on mydriasis of the solution and of its individual components.

METHODS

We developed the ophthalmic solution by mixing 10 mL of 0.5% tropicamide/0.5% phenylephrine, 10 mL of 5% phenylephrine and 10 mL of 0.1% diclofenac (TPD). We determined the stability of the chemicals in solution using high-performance liquid chromatography immediately, 1 week and 1 month after mixing. Corneal epithelial barrier function was assessed before and after instillation of the solutions in 26 eyes of 17 patients (5 with proliferative diabetic retinopathy or diabetic maculopathy, 8 with cataract and 4 with no eye disease). The fluorescent intensity was measured 10 times at the central cornea 30 minutes after instillation of 3 mL of 0.5% fluorescein solution and the average value calculated. Finally, the pupil diameter of 50 eyes of 38 patients undergoing cataract surgery was measured before and immediately after the operation.

RESULTS

No remarkable changes in the pH or pharmacologic activity of the TPD solution were observed at any time after mixing. In the patients with diabetic retinopathy or cataract, the increase in mean fluorescent intensity was significantly greater with the individual solutions than with the TPD solution (p < 0.01); there was no significant difference in mean fluorescent intensity in the subjects with no eye disease. No statistically significant difference in pupil diameter was observed between the eyes that received the TPD solution and those that received the individual solutions.

INTERPRETATION

TPD ophthalmic solution is simple to prepare and use. The TPD solution had a similar effect on mydriasis as the three individual solutions but was less destructive to the corneal epithelium.

Late corneal perforation after photorefractive keratectomy associated with topical diclofenac: involvement of matrix metalloproteinases

OBJECTIVE

To report a case of a 50-year-old man who was initially seen with a corneal perforation in his right eye 2 months after a photorefractive keratectomy (PRK) procedure and to discuss the roles of topical diclofenac and matrix metalloproteinases (MMPs).

DESIGN

Case report with tissue analysis.

MAIN OUTCOME MEASURES

Ocular examination, diagnostic workup, surgical treatment, and histologic, immunofluorescent, zymography, and real time-polymerase chain reaction studies on corneal button.

RESULTS

Slit-lamp examination of the right eye revealed a 4-mm diameter area of central corneal thinning with a 2-mm diameter perforation at its center. Predisposing factors included prolonged postoperative topical diclofenac therapy for more than 2 months and a 10-year history of well-controlled diabetes mellitus. An extensive diagnostic workup ruled out a systemic autoimmune disease. A penetrating keratoplasty was performed. Results of immunohistochemical studies of the corneal button showed stromal accumulation of temporary type III and IV collagens, MMP-3, and MMP-9 in the anterior wounded stroma and MMP-9 in the basal corneal epithelial cells of the leading edge. Differential activity and expression of MMP-2 and MMP-9 were found between the central and peripheral corneal buttons.

CONCLUSIONS

Prolonged use of diclofenac and diabetes mellitus might be responsible for the corneal perforation after PRK in our patient. MMP-9 and MMP-3 might be involved in delayed wound closure and corneal melting.