Antagonizing NK-1R modulates pain perception following corneal injury.

Substance P (SP) expressed by corneal nerves, is an 11-amino acid long neuropeptide from the tachykinin family, encoded by the Tac1 gene, and binds to neurokinin receptors. SP overexpression is associated with various pathological responses in the cornea including vasodilation, pain, inflammation, and angiogenesis in the normally avascular tissue. This study investigates the role of neurokinin-1 receptor (NK-1R) mediated signaling in nociception, nerve regeneration, and neuronal activation following mechanical corneal injury in mice.

Midterm results after allogeneic simple limbal epithelial transplantation from deceased-donor eyes in patients with persistent corneal epithelial defects due to limbal stem cell deficiency.

Background: This study aims to characterize the clinical outcomes after allogeneic simple limbal epithelial transplantation (alloSLET) utilizing tissue from cadaveric donor eyes to address persistent corneal epithelial defects caused by limbal stem cell deficiency.

Methods: We conducted a retrospective analysis of medical records from 20 patients, encompassing 24 eyes, who underwent alloSLET at least 2 years prior. The primary endpoint was the achievement of complete epithelialization of the corneal surface by corneal epithelium.

Assessment of Corneal Graft Outcomes in a Murine Model of Endothelial Keratoplasty.

: In this study, we establish a protocol for evaluating the outcomes of endothelial keratoplasty, including graft survival, rejection, or failure. Additionally, we also evaluate the alloimmune response in graft recipients. : We performed EK using C57BL/6 (allogeneic) and BALB/c (syngeneic) as donors and BALB/c mice as recipients.

Myeloid-derived suppressor cells promote allograft survival by suppressing regulatory T cell dysfunction in high-risk corneal transplantation.

Highly inflamed and neovascularized corneal graft beds are known as high-risk (HR) environments for transplant survival. One of the primary factors leading to this rejection is reduction in the suppressive function of regulatory T cells (Treg). Our results show that myeloid-derived suppressor cells (MDSC) counteract interleukin-6-mediated Treg dysfunction by expressing interleukin-10.

Studies on the Effects of Hypercholesterolemia on Mouse Ophthalmic Artery Reactivity.

Atherogenic lipoproteins may impair vascular reactivity, leading to tissue damage in various organs, including the eye. This study aimed to investigate whether ophthalmic artery reactivity is affected in mice lacking the apolipoprotein E gene (ApoE-/-), a model for hypercholesterolemia and atherosclerosis. Twelve-month-old male ApoE-/- mice and age-matched wild-type controls were used to assess vascular reactivity using videomicroscopy.

The Neuropeptide α-Melanocyte-Stimulating Hormone Prevents Persistent Corneal Edema following Injury.

Corneal endothelial cells (CEnCs) regulate corneal hydration and maintain tissue transparency through their barrier and pump function. However, these cells exhibit limited regenerative capacity following injury. Currently, corneal transplantation is the only established therapy for restoring endothelial function, and there are no pharmacologic interventions available for restoring endothelial function.

Insights into mustard gas keratopathy- characterizing corneal layer-specific changes in mice exposed to nitrogen mustard.

Exposure to mustard agents, such as sulfur mustard (SM) and nitrogen mustard (NM), often results in ocular surface damage. This can lead to the emergence of various corneal disorders that are collectively referred to as mustard gas keratopathy (MGK). In this study, we aimed to develop a mouse model of MGK by using ocular NM exposure, and describe the subsequent structural changes analyzed across the different layers of the cornea.

The impact of donor diabetes on corneal transplant immunity.

Corneal transplantation is the most common form of solid tissue grafting, with an approximately 80% to 90% success rate. However, success rates may decline when donor tissues are derived from patients with a history of diabetes mellitus (DM). To evaluate the underlying immunopathologic processes that cause graft rejection, we used streptozotocin-induced type 1 DM (DM1) and transgenic Lep type 2 DM (DM2) diabetic murine models as donors and nondiabetic BALB/c as recipients.

Insights into mustard gas keratopathy: Characterizing corneal layer-specific changes in mice exposed to nitrogen mustard.

Exposure to mustard agents, such as sulfur mustard (SM) and nitrogen mustard (NM), often results in ocular surface damage. This can lead to the emergence of various corneal disorders that are collectively referred to as mustard gas keratopathy (MGK). In this study, we aimed to develop a mouse model of MGK by using ocular NM exposure, and describe the subsequent structural changes analyzed across the different layers of the cornea.

Effects of Resveratrol on Vascular Function in Retinal Ischemia-Reperfusion Injury.

Ischemia-reperfusion (I/R) events are involved in the development of various ocular pathologies, e.g., retinal artery or vein occlusion.

Amplified Natural Killer Cell Activity and Attenuated Regulatory T-cell Function Are Determinants for Corneal Alloimmunity in Very Young Mice.

Background: Corneal transplantation outcomes are generally less favorable in young children compared with adults. The purpose of this study was to determine the immunological mechanisms underlying this difference.

Methods: A murine model of allogeneic corneal transplantation was used in the study, and graft survival was determined by evaluating opacity scores for 8 wk.

A Novel Murine Model of Endothelial Keratoplasty.

Purpose: The purpose of this study was to establish a murine model of endothelial keratoplasty.

Methods: Endothelial keratoplasty (EK) was performed using C57BL/6 donor and BALB/c recipient mice. The central endothelium and Descemet membrane were removed from the recipient cornea, and a 1.

Risk factors for peripheral hypertrophic subepithelial corneal opacification.

Background: To evaluate the phenotype, tear secretion and refractive changes of patients diagnosed with peripheral hypertrophic subepithelial corneal opacification (PHSCO).

Methods: This is a retrospective, interventional case series conducted at the Department of Ophthalmology, University Medical Center of the Johannes Gutenberg University Mainz. Medical records of patients diagnosed with PHSCO were analysed.

Ocular pain in ocular graft-versus-host disease patients with neurotrophic keratopathy.

Purpose: Neurotrophic keratopathy (NK) is a degenerative disorder of the cornea characterized by decreased sensory innervation, epitheliopathy, and impaired epithelial healing. In this study, we assessed ocular pain and quality-of-life-related parameters in ocular graft-versus-host disease (oGVHD) patients with and without NK.

Methods: We included 213 oGVHD patients in this retrospective study, including 29 patients with NK assessed by the Cochet-Bonnet esthesiometer.

Modulating the tachykinin: Role of substance P and neurokinin receptor expression in ocular surface disorders.

Substance P (SP) is a tachykinin expressed by various cells in the nervous and immune systems. SP is predominantly released by neurons and exerts its biological and immunological effects through the neurokinin receptors, primarily the neurokinin-1 receptor (NK1R). SP is essential for maintaining ocular surface homeostasis, and its reduced levels in disorders like diabetic neuropathy disrupt the corneal tissue.

Promotion of corneal angiogenesis by sensory neuron-derived calcitonin gene-related peptide.

The normal cornea has no blood vessels but has abundant innervation. There is emerging evidence that sensory nerves, originated from the trigeminal ganglion (TG) neurons, play a key role in corneal angiogenesis. In the current study, we examined the role of TG sensory neuron-derived calcitonin gene-related peptide (CGRP) in promoting corneal neovascularization (CNV).

Five Years Follow-Up of Acrysof Cachet® Angle-Supported Phakic Intraocular Lens Implantation for Myopia Correction.

Purpose: The Acrysof Cachet® angle-supported phakic intraocular lens (pIOL) (Alcon Laboratories, Inc., Fort Worth, TX) is designed to correct high refractive errors in human eyes. The aim of this study was to evaluate the outcome of AcrySof Cachet® angle-supported pIOL implantation with particular regard to efficacy and safety of the implant over a 60-month follow-up period.

Acute Hydrops After Bowman Layer Transplantation for Keratoconus May Indicate that Descemet Membrane Rupture Is Secondary to Hydrops.

Purpose: The aim of this study was to review the postoperative course and imaging features of 7 eyes that presented with corneal hydrops after Bowman layer (BL) transplantation was performed for advanced keratoconus to determine the potential mechanisms of hydrops formation.

Methods: A retrospective analysis was performed of 7 eyes of 5 patients with advanced keratoconus that underwent midstromal BL transplantation at 2 tertiary referral centers and developed acute corneal hydrops on average 64 (±30) months (range 14-104 months) postoperatively. Corneal tomography and anterior segment optical coherence tomography (AS-OCT) images were reviewed to document the postoperative and posthydrops course.

Betulinic Acid Protects from Ischemia-Reperfusion Injury in the Mouse Retina.

Ischemia/reperfusion (I/R) events are involved in the pathophysiology of numerous ocular diseases. The purpose of this study was to test the hypothesis that betulinic acid protects from I/R injury in the mouse retina. Ocular ischemia was induced in mice by increasing intraocular pressure (IOP) to 110 mm Hg for 45 min, while the fellow eye served as a control.

Corneal Epithelial Stem Cells-Physiology, Pathophysiology and Therapeutic Options.

In the human cornea, regeneration of the epithelium is regulated by the stem cell reservoir of the limbus, which is the marginal region of the cornea representing the anatomical and functional border between the corneal and conjunctival epithelium. In support of this concept, extensive limbal damage, e.g.

Aged Mice Devoid of the M Muscarinic Acetylcholine Receptor Develop Mild Dry Eye Disease.

The parasympathetic nervous system is critically involved in the regulation of tear secretion by activating muscarinic acetylcholine receptors. Hence, various animal models targeting parasympathetic signaling have been developed to induce dry eye disease (DED). However, the muscarinic receptor subtype (M-M) mediating tear secretion remains to be determined.

Oxidative Stress and Vascular Dysfunction in the Retina: Therapeutic Strategies.

Many retinal diseases, such as diabetic retinopathy, glaucoma, and age-related macular (AMD) degeneration, are associated with elevated reactive oxygen species (ROS) levels. ROS are important intracellular signaling molecules that regulate numerous physiological actions, including vascular reactivity and neuron function. However, excessive ROS formation has been linked to vascular endothelial dysfunction, neuron degeneration, and inflammation in the retina.

Effects of Superficial Keratectomy in Peripheral Hypertrophic Subepithelial Corneal Opacification on Front and Back Corneal Astigmatism.

Purpose: To evaluate changes of anterior and posterior corneal astigmatism after superficial keratectomy in peripheral hypertrophic subepithelial corneal opacification (PHSCO).

Methods: Patients with PHSCO, who had received superficial keratectomy with mitomycin C 0.02%, were included in this retrospective study.

Allogenic simple limbal epithelial transplantation (alloSLET) from cadaveric donor eyes in patients with persistent corneal epithelial defects.

Background/aim: To describe the clinical outcome of allogenic simple limbal epithelial transplantation (alloSLET) utilising tissue from cadaveric donor eyes after failed re-epithelialisation of the corneal surface.

Methods: Medical records of 14 eyes from 14 patients treated for persistent corneal epithelial defects with alloSLET were reviewed. The primary outcome measure was complete epithelialisation of the corneal surface.