RESUMEN
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. This study investigated the efficacy of the neuropeptide α-melanocyte-stimulating hormone (α-MSH) in promoting endothelial regeneration during the critical window between ocular injury and the onset of endothelial decompensation using an established murine model of injury using transcorneal freezing. Local administration of α-MSH following injury prevented corneal edema and opacity, reduced leukocyte infiltration, and limited CEnC apoptosis while promoting their proliferation. These results suggest that α-MSH has a proregenerative and cytoprotective function on CEnCs and shows promise as a therapy for the prevention and management of corneal endothelial dysfunction.
Asunto(s)
Córnea , Edema Corneal , alfa-MSH , Femenino , Embarazo , Animales , Ratones , Ratones Endogámicos BALB C , Humanos , Línea Celular , Córnea/citología , Células Endoteliales , Edema Corneal/tratamiento farmacológico , Edema Corneal/patología , Conservación de Tejido , alfa-MSH/uso terapéutico , Citoprotección , Infiltración Neutrófila , Monocitos/metabolismo , Macrófagos/metabolismo , Cicatrización de Heridas/efectos de los fármacosRESUMEN
Corneal transplantation is the most common form of tissue transplantation. The success of corneal transplantation mainly relies on the integrity of corneal endothelial cells (CEnCs), which maintain tissue transparency by pumping out excess water from the cornea. After transplantation, the rate of CEnC loss far exceeds that seen with normal aging, which can threaten sight. The underlying mechanisms are poorly understood. Alpha-melanocyte-stimulating hormone (α-MSH) is a neuropeptide that is constitutively found in the aqueous humor with both cytoprotective and immunomodulatory effects. The curent study found high expression of melanocortin 1 receptor (MC1R), the receptor for α-MSH, on CEnCs. The effect of α-MSH/MC1R signaling on endothelial function and allograft survival in vitro and in vivo was investigated using MC1R signaling-deficient mice (Mc1re/e mice with a nonfunctional MC1R). Herein, the results indicate that in addition to its well-known immunomodulatory effect, α-MSH has cytoprotective effects on CEnCs after corneal transplantation, and the loss of MC1R signaling significantly decreases long-term graft survival in vivo. In conclusion, α-MSH/MC1R signaling is critical for CEnC function and graft survival after corneal transplantation.
Asunto(s)
Córnea/inmunología , Trasplante de Córnea , Células Endoteliales/inmunología , Supervivencia de Injerto/inmunología , Transducción de Señal/inmunología , alfa-MSH/inmunología , Animales , Línea Celular Transformada , Córnea/patología , Femenino , Supervivencia de Injerto/genética , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Receptor de Melanocortina Tipo 1/genética , Receptor de Melanocortina Tipo 1/inmunología , Transducción de Señal/genética , alfa-MSH/genéticaRESUMEN
Fuchs Endothelial Corneal Dystrophy (FECD), a late-onset oxidative stress disorder, is the most common cause of corneal endothelial degeneration and is genetically associated with CTG repeat expansion in Transcription Factor 4 (TCF4). We previously reported accumulation of nuclear (nDNA) and mitochondrial (mtDNA) damage in FECD. Specifically, mtDNA damage was a prominent finding in development of disease in the ultraviolet-A (UVA) induced FECD mouse model. We hypothesize that an aberrant DNA repair may contribute to the increased DNA damage seen in FECD. We analyzed differential expression profiles of 84 DNA repair genes by real-time PCR arrays using Human DNA Repair RT-Profiler plates using cDNA extracted from Descemet's membrane-corneal endothelium (DM-CE) obtained from FECD patients with expanded (>40) or non-expanded (<40) intronic CTG repeats in TCF4 gene and from age-matched normal donors. Change in mRNA expression of <0.5- or >2.0-fold in FECD relative to normal was set as cutoff for down- or upregulation. Downregulated mitochondrial genes were further validated using the UVA-based mouse model of FECD. FECD specimens exhibited downregulation of 9 genes and upregulation of 8 genes belonging to the four major DNA repair pathways, namely, base excision repair (BER), nucleotide excision repair (NER), mismatch repair (MMR), and double strand break (DSB) repair, compared to normal donors. MMR gene MSH2 and BER gene POLB were preferentially upregulated in expanded FECD. BER genes LIG3 and NEIL2, DSB repair genes PARP3 and TOP3A, NER gene XPC, and unclassified pathway gene TREX1, were downregulated in both expanded and non-expanded FECD. MtDNA repair genes, Lig3, Neil2, and Top3a, were also downregulated in the UVA-based mouse model of FECD. Our findings identify impaired DNA repair pathways that may play an important role in DNA damage due to oxidative stress as well as genetic predisposition noted in FECD.
Asunto(s)
ADN Glicosilasas , Distrofia Endotelial de Fuchs , Animales , Ratones , Humanos , Distrofia Endotelial de Fuchs/genética , Distrofia Endotelial de Fuchs/metabolismo , Endotelio Corneal/metabolismo , Predisposición Genética a la Enfermedad , Reparación del ADN/genética , ADN Mitocondrial/genética , ADN Glicosilasas/genética , ADN Glicosilasas/metabolismoRESUMEN
Fuchs endothelial corneal dystrophy (FECD) is a leading cause of corneal endothelial (CE) degeneration resulting in impaired visual acuity. It is a genetically complex and age-related disorder, with higher incidence in females. In this study, we established a nongenetic FECD animal model based on the physiologic outcome of CE susceptibility to oxidative stress by demonstrating that corneal exposure to ultraviolet A (UVA) recapitulates the morphological and molecular changes of FECD. Targeted irradiation of mouse corneas with UVA induced reactive oxygen species (ROS) production in the aqueous humor, and caused greater CE cell loss, including loss of ZO-1 junctional contacts and corneal edema, in female than male mice, characteristic of late-onset FECD. UVA irradiation caused greater mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) damage in female mice, indicative of the sex-driven differential response of the CE to UVA, thus accounting for more severe phenotype in females. The sex-dependent effect of UVA was driven by the activation of estrogen-metabolizing enzyme CYP1B1 and formation of reactive estrogen metabolites and estrogen-DNA adducts in female but not male mice. Supplementation of N-acetylcysteine (NAC), a scavenger of reactive oxygen species (ROS), diminished the morphological and molecular changes induced by UVA in vivo. This study investigates the molecular mechanisms of environmental factors in FECD pathogenesis and demonstrates a strong link between UVA-induced estrogen metabolism and increased susceptibility of females for FECD development.
Asunto(s)
Citocromo P-450 CYP1B1/metabolismo , Aductos de ADN/efectos de la radiación , Daño del ADN/efectos de la radiación , Estrógenos/metabolismo , Distrofia Endotelial de Fuchs/etiología , Rayos Ultravioleta/efectos adversos , Acetilcisteína/administración & dosificación , Animales , Humor Acuoso/efectos de los fármacos , Humor Acuoso/metabolismo , Humor Acuoso/efectos de la radiación , Aductos de ADN/metabolismo , Daño del ADN/efectos de los fármacos , ADN Mitocondrial/metabolismo , ADN Mitocondrial/efectos de la radiación , Modelos Animales de Enfermedad , Endotelio Corneal/efectos de los fármacos , Endotelio Corneal/patología , Endotelio Corneal/efectos de la radiación , Femenino , Depuradores de Radicales Libres/administración & dosificación , Distrofia Endotelial de Fuchs/diagnóstico , Distrofia Endotelial de Fuchs/tratamiento farmacológico , Distrofia Endotelial de Fuchs/patología , Humanos , Masculino , Ratones , Estrés Oxidativo/efectos de la radiación , Especies Reactivas de Oxígeno/metabolismo , Índice de Severidad de la EnfermedadRESUMEN
Corneal endothelium (CE) is a monolayer of mitochondria-rich cells, critical for maintaining corneal transparency compatible with clear vision. Fuchs endothelial corneal dystrophy (FECD) is a heterogeneous, genetically complex disorder, where oxidative stress plays a key role in the rosette formation during the degenerative loss of CE. Increased mitochondrial fragmentation along with excessive mitophagy activation has been detected in FECD; however, the mechanism of aberrant mitochondrial dynamics in CE cell loss is poorly understood. Here, the role of oxidative stress in mitophagy activation in FECD is investigated. Immunoblotting of FECD ex vivo specimens revealed an accumulation of PINK1 and phospho-Parkin (Ser65) along with loss of total Parkin and total Drp1. Similarly, modeling of rosette formation with menadione (MN), led to phospho-Parkin accumulation in fragmented mitochondria resulting in mitophagy-induced mitochondrial clearance, albeit possibly in a PINK1-independent manner. Loss of PINK1, phospho-Drp1, and total Drp1 was prominent after MN-induced oxidative stress, but not after mitochondrial depolarization by carbonyl cyanide m-chlorophenyl hydrazone. Moreover, MN-induced mitophagy led to degradation of Parkin along with sequestration of Drp1 and PINK1 that was rescued by mitophagy inhibition. This study shows that in FECD, intracellular oxidative stress induces Parkin-mediated mitochondrial fragmentation where endogenous Drp1 and PINK1 are sequestered and degraded by mitophagy during degenerative loss of post-mitotic cells of ocular tissue.
Asunto(s)
Endotelio Corneal/patología , Distrofia Endotelial de Fuchs/patología , Mitocondrias/patología , Proteínas Mitocondriales/metabolismo , Mitofagia , Proteínas Quinasas/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Antifibrinolíticos/farmacología , Endotelio Corneal/efectos de los fármacos , Endotelio Corneal/metabolismo , Distrofia Endotelial de Fuchs/genética , Distrofia Endotelial de Fuchs/metabolismo , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Proteínas Mitocondriales/genética , Estrés Oxidativo , Proteínas Quinasas/genética , Transducción de Señal , Ubiquitina-Proteína Ligasas/genética , Vitamina K 3/farmacologíaRESUMEN
Corneal transplantation is the most prevalent form of tissue transplantation. The success of corneal transplantation mainly relies on the integrity of corneal endothelial cells (CEnCs), which maintain graft transparency. CEnC density decreases significantly after corneal transplantation even in the absence of graft rejection. To date, different strategies have been used to enhance CEnC survival. The neuropeptide vasoactive intestinal peptide (VIP) improves CEnC integrity during donor cornea tissue storage and protects CEnCs against oxidative stress-induced apoptosis. However, little is known about the effect of exogenous administration of VIP on corneal transplant outcomes. We found that VIP significantly accelerates endothelial wound closure and suppresses interferon-γ- and tumor necrosis factor-α-induced CEnC apoptosis in vitro in a dose-dependent manner. In addition, we found that intracameral administration of VIP to mice undergoing syngeneic corneal transplantation with endothelial injury increases CEnC density and decreases graft opacity scores. Finally, using a mouse model of allogeneic corneal transplantation, we found for the first time that treatment with VIP significantly suppresses posttransplantation CEnC loss and improves corneal allograft survival.
Asunto(s)
Trasplante de Córnea , Endotelio Corneal/efectos de los fármacos , Fármacos Gastrointestinales/farmacología , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Péptido Intestinal Vasoactivo/farmacología , Cicatrización de Heridas/efectos de los fármacos , Aloinjertos , Animales , Células Cultivadas , Endotelio Corneal/lesiones , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BLRESUMEN
Two cases of limbal cysts lined by nonkeratinizing epithelium were studied with a panel of cytokeratins. One was a long-standing lesion in a 30-year-old man, whereas the other was excised from a 40-year-old man following pterygium surgery. Each cyst was immunostained with a panel of cytokeratins that were specific exclusively and separately for corneal and conjunctival epithelia. The epithelial lining of each cyst was CK12 positive for corneal epithelium and CK13 negative for conjunctival epithelium. It is hypothesized that a subset of corneoscleral cysts contain corneal epithelium, probably derived from a type of limbal stem cell differentiation.
Asunto(s)
Enfermedades de la Córnea/diagnóstico , Quistes/diagnóstico , Queratinas/metabolismo , Limbo de la Córnea/patología , Adulto , Biomarcadores/metabolismo , Biopsia , Enfermedades de la Córnea/metabolismo , Quistes/metabolismo , Humanos , Limbo de la Córnea/metabolismo , MasculinoRESUMEN
Human corneal endothelial cells are derived from neural crest and because of postmitotic arrest lack competence to repair cell loss from trauma, aging, and degenerative disorders such as Fuchs endothelial corneal dystrophy (FECD). Herein, we identified a rapidly proliferating subpopulation of cells from the corneal endothelium of adult normal and FECD donors that exhibited features of neural crest-derived progenitor (NCDP) cells by showing absence of senescence with passaging, propensity to form spheres, and increased colony forming efficacy compared with the primary cells. The collective expression of stem cell-related genes SOX2, OCT4, LGR5, TP63 (p63), as well as neural crest marker genes PSIP1 (p75(NTR)), PAX3, SOX9, AP2B1 (AP-2ß), and NES, generated a phenotypic footprint of endothelial NCDPs. NCDPs displayed multipotency by differentiating into microtubule-associated protein 2, ß-III tubulin, and glial fibrillary acidic protein positive neurons and into p75(NTR)-positive human corneal endothelial cells that exhibited transendothelial resistance of functional endothelium. In conclusion, we found that mitotically incompetent ocular tissue cells contain adult NCDPs that exhibit a profile of transcription factors regulating multipotency and neural crest progenitor characteristics. Identification of normal NCDPs in FECD-affected endothelium holds promise for potential autologous cell therapies.
Asunto(s)
Células Progenitoras Endoteliales/metabolismo , Endotelio Corneal/patología , Distrofia Endotelial de Fuchs/patología , Adulto , Anciano , Biomarcadores/metabolismo , Células Progenitoras Endoteliales/patología , Endotelio Corneal/metabolismo , Femenino , Distrofia Endotelial de Fuchs/metabolismo , Humanos , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Cresta Neural/metabolismo , Cresta Neural/patología , Fenotipo , Tubulina (Proteína)RESUMEN
PURPOSE: To validate the Ocular Pain Assessment Survey (OPAS), specifically designed to measure ocular pain and quality of life for use by eye care practitioners and researchers. DESIGN: A single-center cohort study was conducted among patients with and without corneal and ocular surface pain at initial and follow-up visits over a 6-month period. The content of the OPAS was guided by literature review, a body of experts, and incorporating conceptual frameworks from existing pain questionnaires. The Wong-Baker FACES Pain Rating Scale served as the gold standard for measuring the intensity of ocular pain. PARTICIPANTS: A total of 102 patients aged 18 to 80 years completed the OPAS at the initial visit. A total of 21 patients were followed up after treatment. METHODS: Indices of validity and internal consistency (Spearman's rank-order, rs, or Pearson's correlation coefficients, rp), and coefficient of reliability (Cronbach's α) were determined in addition to equivalence testing, exploratory factor analysis (EFA), and diagnostic analysis. MAIN OUTCOME MEASURES: Eye pain intensity was the primary outcome measure, and interference with quality of life (QoL), aggravating factors, associated factors, associated non-eye pain intensity, and self-reported symptomatic relief were the secondary outcome measures. RESULTS: The OPAS had criterion validity at both initial (rs = 0.71; n = 102; P < 0.01) and follow-up visits (rs = 0.97; n = 21; P < 0.01). Equivalence tests yielded OPAS and gold standard equivalence for both the initial and follow-up visits. The EFA supported 6 subscales (eye pain intensity at 24 hours and 2 weeks, non-eye pain intensity, QoL, aggravating factors, and associated factors) confirming multidimensionality. Cronbach's α >0.83 for all subscales established strong internal consistency, which correlated with the gold standard, including 24-hour eye pain intensity and QoL interference scores (rp = 0.81, 0.64, respectively P < 0.001). At follow-up, reduction in pain scores was accompanied by improvement in all dimensions of the OPAS. Percentage change in QoL correlated to percentage change in the gold standard (rp = 0.53; P < 0.05). The OPAS was sensitive (94%), specific (81%), and accurate (91%), with a diagnostic odds ratio >50. CONCLUSIONS: The OPAS is a valid, reliable, and responsive tool with strong psychometric and diagnostic properties in the multidimensional quantification of corneal and ocular surface pain intensity, and QoL.
Asunto(s)
Dolor Ocular/diagnóstico , Dimensión del Dolor/métodos , Encuestas y Cuestionarios/normas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades de la Córnea/diagnóstico , Análisis Factorial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor/normas , Psicometría/normas , Calidad de Vida , Reproducibilidad de los Resultados , Adulto JovenRESUMEN
The cornea is covered by a stratified epithelium that is renewed by stem cells located in the peripheral region of the cornea known as the limbus. This stroma of the limbus contains stromal keratocytes that, when expanded in culture, are termed limbal fibroblasts (LFs). It is thought that LFs exhibit similar characteristics to bone marrow mesenchymal stem cells (BM MSCs) and help maintain the epithelial stem cell phenotype in the limbal region. In this study, we aimed at reprogramming stage-specific embryonic antigen-4 (SSEA4+) LFs and BM MSCs into corneal epithelial lineage using a three-dimensional culture system and embryonic stem cell medium. After enrichment, SSEA4+ cells showed a higher level of stem cell marker expression such as Sox2, Oct4, Nanog, Rex1, ABCG2, and TRA-1-60, and colony-forming efficiency than did SSEA4- cells. SSEA4+, as compared to SSEA4- cells, had a greater propensity to form spheres that, in turn, were induced into ectodermal lineage and further differentiated into functional corneal epithelium. Results show that LFs were similar to BM MSCs in marker profiles, and together with the differences noted between SSEA4+ and SSEA4- cells, point to LFs' being tissue-specific MSCs. However, LFs showed a greater potential for differentiation into corneal epithelium, indicating the potential importance of tissue-specific adult progenitors in their reprogramming capacity into cells of interest. This study opens a new avenue for investigating the molecular mechanism involved in maintaining a limbal stem cell niche and thus a potentially important clinical application to treat corneal epithelial stem cell loss.
Asunto(s)
Células de la Médula Ósea/citología , Diferenciación Celular , Células Epiteliales/citología , Epitelio Corneal/citología , Fibroblastos/citología , Limbo de la Córnea/citología , Células Madre Mesenquimatosas/citología , Adulto , Biomarcadores/metabolismo , Células de la Médula Ósea/metabolismo , Linaje de la Célula , Separación Celular , Células Cultivadas , Ectodermo/citología , Impedancia Eléctrica , Células Epiteliales/metabolismo , Fibroblastos/metabolismo , Técnica del Anticuerpo Fluorescente , Humanos , Células Madre Mesenquimatosas/metabolismo , Modelos Biológicos , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Antígenos Embrionarios Específico de Estadio/metabolismoRESUMEN
PURPOSE: The purpose of this study was to evaluate the outcomes of phacoemulsification in patients with ocular graft-versus-host disease (GVHD). METHODS: The occurrence of cataracts, cataract surgery, and its outcomes were analyzed in the medical records of 229 patients (458 eyes) with ocular GVHD. Outcome measures included pre- and postoperative corrected distance visual acuity (CDVA) and the rate of postoperative complications. RESULTS: Of the 458 eyes evaluated, 58 were pseudophakic; from the 400 phakic eyes, 238 (59 %) presented with cataracts and 62 (26 %) underwent cataract surgery. Analysis of postoperative complications and visual outcomes at 1 month was performed in 51 eyes in which detailed surgical and immediate postoperative records were available. Preoperatively, the mean CDVA was 0.67 ± 0.57 LogMAR (Snellen 20/93), improving postoperatively to 0.17 ± 0.18 (Snellen 20/29) at 1 month (P < 0.0001), and to 0.13 ± 0.14 (Snellen 20/26) by the final follow-up visit (P < 0.0001). Postoperative complications included corneal epithelial defects (8 %), filamentary keratitis (6 %), worsening of corneal epitheliopathy (16 %), posterior capsular opacification (18 %), and cystoid macular edema (4 %). A corrected distance visual acuity of 20/30 or better was achieved in 87 % of the eyes; suboptimal CDVA improvement was attributable to severe ocular surface disease, pre-existing advanced glaucoma, and prior macular surgery. CONCLUSIONS: Phacoemulsification in patients with chronic ocular GVHD is a safe and efficacious procedure resulting in significant visual improvement. Overall, postoperative adverse events responded well to timely management.
Asunto(s)
Catarata/complicaciones , Oftalmopatías/complicaciones , Enfermedad Injerto contra Huésped/complicaciones , Implantación de Lentes Intraoculares , Facoemulsificación , Adulto , Anciano , Humanos , Persona de Mediana Edad , Complicaciones Posoperatorias , Seudofaquia/fisiopatología , Estudios Retrospectivos , Resultado del Tratamiento , Agudeza Visual/fisiología , Adulto JovenRESUMEN
Background: Boston Keratoprosthesis Type I (BI-KPro I) is a synthetic cornea that can be used to restore vision in patients with corneal blindness. This retrospective study evaluated the outcomes of BI-KPro implantation in 118 patients. Material: The mean age of the patients was 56.76 ± 14.24 years. Indications for keratoprosthesis implantation were as follows: graft failure, 47 (39.83%); ocular burn, 38 (32.20%); neurotrophic keratopathy, 11 (9.32%), mucous membrane pemphigoid 9 (7.67%); autoimmune, 6 (5.08%); Stevens-Johnson syndrome, 4 (3.39%); and aniridia (2.54%). Methods: The surgeries were performed between March 2019 and June 2022 at a single clinical center in two locations. The postoperative visual acuity, complications, and need for additional surgical procedures were analyzed. Results: The Best Corrected Visual Acuity before surgery was 0.01 ± 0.006. After one year (V1), it was 0.30 ± 0.27; at two years (V2), it was 0.27 ± 0.26; and at three years (V3), it was 0.21 ± 0.23. The percentage of patients with visual acuity better than 0.1 on the Snellen chart was 37.29% after 1 year, 49.35% after 2 years, and 46.81% after 3 years of follow up. The most common complications were glaucoma (78 patients; 66.1%), corneal melting (22 patients; 18.6%), and retroprosthetic membranes (20 patients; 17.0%). Conclusions: The BI-KPro can significantly improve visual acuity. The worst long-term results were obtained in the group of patients with autoimmune diseases; therefore, careful consideration should be given to implanting BI-KPro in this group. The high incidence of de novo glaucoma or the progression of pre-existing glaucoma suggests the need for careful monitoring.
RESUMEN
Descemet's Stripping Only (DSO) is a surgical technique that utilizes the peripheral corneal endothelial cell (CEnC) migration for wound closure. Ripasudil, a Rho-associated protein kinase (ROCK) inhibitor, has shown potential in DSO treatment; however, its mechanism in promoting CEnC migration remains unclear. We observed that ripasudil-treated immortalized normal and Fuchs endothelial corneal dystrophy (FECD) cells exhibited significantly enhanced migration and wound healing, particularly effective in FECD cells. Ripasudil upregulated mRNA expression of Snail Family Transcriptional Repressor (SNAI1/2) and Vimentin (VIM) while decreasing Cadherin (CDH1), indicating endothelial-to-mesenchymal transition (EMT) activation. Ripasudil activated Rac1, driving the actin-related protein complex (ARPC2) to the leading edge, facilitating enhanced migration. Ex vivo studies on cadaveric and FECD Descemet's membrane (DM) showed increased migration and proliferation of CEnCs after ripasudil treatment. An ex vivo DSO model demonstrated enhanced migration from the DM to the stroma with ripasudil. Coating small incision lenticule extraction (SMILE) tissues with an FNC coating mix and treating the cells in conjunction with ripasudil further improved migration and resulted in a monolayer formation, as detected by the ZO-1 junctional marker, thereby leading to the reduction in EMT. In conclusion, ripasudil effectively enhanced cellular migration, particularly in a novel ex vivo DSO model, when the stromal microenvironment was modulated. This suggests ripasudil as a promising adjuvant for DSO treatment, highlighting its potential clinical significance.
Asunto(s)
Movimiento Celular , Distrofia Endotelial de Fuchs , Quinasas Asociadas a rho , Humanos , Quinasas Asociadas a rho/metabolismo , Quinasas Asociadas a rho/antagonistas & inhibidores , Movimiento Celular/efectos de los fármacos , Distrofia Endotelial de Fuchs/patología , Distrofia Endotelial de Fuchs/tratamiento farmacológico , Isoquinolinas/farmacología , Sulfonamidas/farmacología , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Endotelio Corneal/efectos de los fármacos , Endotelio Corneal/metabolismo , Endotelio Corneal/patología , Lámina Limitante Posterior/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Queratoplastia Endotelial de la Lámina Limitante Posterior/métodos , Proliferación Celular/efectos de los fármacos , Modelos Biológicos , Cicatrización de Heridas/efectos de los fármacosRESUMEN
Fuchs endothelial corneal dystrophy (FECD) is a genetically complex, age-related, female-predominant disorder characterized by loss of post-mitotic corneal endothelial cells (CEnCs). Ultraviolet-A (UVA) light has been shown to recapitulate the morphological and molecular changes seen in FECD to a greater extent in females than males, by triggering CYP1B1 upregulation in females. Herein, we investigated the mechanism of greater CEnC susceptibility to UVA in females by studying estrogen metabolism in response to UVA in the cornea. Loss of NAD(P)H quinone oxidoreductase 1 (NQO1) resulted in increased production of estrogen metabolites and mitochondrial-DNA adducts, with a higher CEnC loss in Nqo1-/- female compared to wild-type male and female mice. The CYP1B1 inhibitors, trans-2,3',4,5'-tetramethoxystilbene (TMS) and berberine, rescued CEnC loss. Injection of wild-type male mice with estrogen (E2; 17ß-estradiol) increased CEnC loss, followed by increased production of estrogen metabolites and mitochondrial DNA (mtDNA) damage, not seen in E2-treated Cyp1b1-/-male mice. This study demonstrates that the endo-degenerative phenotype is driven by estrogen metabolite-dependent CEnC loss that is exacerbated in the absence of NQO1; thus, explaining the mechanism accounting for the higher incidence of FECD in females. The mitigation of estrogen-adduct production by CYP1B1 inhibitors could serve as a novel therapeutic strategy for FECD.
Asunto(s)
Distrofia Endotelial de Fuchs , Masculino , Femenino , Ratones , Animales , Distrofia Endotelial de Fuchs/genética , Células Endoteliales/metabolismo , Estrógenos , Daño del ADN , Córnea/metabolismo , ADN Mitocondrial/genéticaRESUMEN
Corneal transplant surgery after chemical or thermal burns has a very low success rate. Vision in these patients can be restored by using an artificial cornea (keratoprosthesis). In this report, we present 5 clinical cases of implanting a fresh corneal graft with Boston type 1 keratoprosthesis in patients with corneas inappropriate for standard corneal transplantation. The mean follow-up was 26.4 months (range, 12 to 36 months; SD, 13.1). The main measures of outcomes were visual acuity and keratoprosthesis stability. At least 1 year after the operation (5 eyes), vision acuity was >0.1 in 100% of the eyes and >0.4 in 50% of the eyes. Retention of the initial keratoprosthesis was 100%. The results of this study seem to be similar to those reported internationally. The anatomical and visual functions of the eyes were stable after keratoprosthesis implantation, though for a longer follow-up period, additional surgical procedures may be required.
Asunto(s)
Córnea/cirugía , Lesiones de la Cornea/cirugía , Trasplante de Córnea , Prótesis e Implantes , Implantación de Prótesis , Adulto , Anciano de 80 o más Años , Quemaduras Químicas/cirugía , Lesiones de la Cornea/inducido químicamente , Quemaduras Oculares/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana EdadRESUMEN
PURPOSE: There are limited data about long-term durability of endothelial rejuvenation after Descemet stripping only (DSO). This study reports a case of bilaterally recurrent endothelial dysfunction and guttae formation after initially successful DSO in combination with cataract extraction (DSO-CE). METHODS: This is a retrospective case report. A 49-year-old man with Fuchs endothelial corneal dystrophy with bilateral visually significant endothelial guttae (predominantly confluent centrally) and concomitant cataract underwent DSO-CE bilaterally. Postoperative course to long-term outcome at 6 years was analyzed. RESULTS: Baseline central corneal thickness (CCT) was 568 µm in OD and 582 µm in OS. Preoperatively, both eyes had no countable central endothelial cells but good peripheral endothelial mosaic. In both eyes, the cornea clinically cleared at approximately 1 month postoperatively after DSO-CE. In short-term follow-up (OD postoperative month 6 and OS postoperative month 3), CCT was 556 µm in OD and 561 µm in OS and central endothelial cell density was 1352 cells/mm 2 in OD and 880 cells/mm 2 in OS. The patient returned to our center in postoperative year 6 OU. At this time, OU had interval formation of guttae within the descemetorhexis, with increased CCT (OD 631 µm and OS 609 µm) and decreased central endothelial cell density (OD 728 cells/mm 2 and OS 609 cells/mm 2 ). CONCLUSIONS: After DSO, progressive endothelial dysfunction with new guttae formation can occur within the descemetorhexis region of repopulated endothelium. Larger analyses with longer follow-up are needed to better characterize long-term outcomes of DSO.
Asunto(s)
Queratoplastia Endotelial de la Lámina Limitante Posterior , Distrofia Endotelial de Fuchs , Masculino , Humanos , Persona de Mediana Edad , Lámina Limitante Posterior/cirugía , Endotelio Corneal/cirugía , Células Endoteliales , Estudios RetrospectivosRESUMEN
OBJECTIVE: To assess the cumulative incidence and risk factors for glaucoma development and progression within 1-2 years following corneal transplant surgery. DESIGN: Retrospective cohort study. METHODS: Patients undergoing penetrating keratoplasty (PK), deep anterior lamellar keratoplasty (DALK), Descemet stripping endothelial keratoplasty (DSEK), Descemet membrane endothelial keratoplasty (DMEK), Boston keratoprosthesis type I (KPro) implantation, or endothelial keratoplasty (DSEK or DMEK) under previous PK (EK under previous PK) at one academic institution with at least 1 year of follow-up were included. Primary outcome measures were cumulative incidence of glaucoma development and progression after corneal transplant, in patients without and with preoperative glaucoma, respectively. Risk factors for glaucoma development and progression were also assessed. RESULTS: Four hundred and thirty-one eyes of 431 patients undergoing PK (113), DALK (17), DSEK (71), DMEK (168), KPro (35) and EK under previous PK (27) with a mean follow-up of 22.9 months were analyzed. The 1-year cumulative incidence for glaucoma development and progression was 28.0% and 17.8% in patients without and with preoperative glaucoma, respectively. In a Cox proportional hazards analysis, DSEK surgery, KPro implantation, average intraocular pressure (IOP) through follow-up and postoperative IOP spikes of ≥30 mmHg were each independently associated with glaucoma development or progression (p < 0.04 for all). CONCLUSIONS: A significant proportion of patients developed glaucoma or exhibited glaucoma progression within 1 year after corneal transplantation. Patient selection for DSEK may partly explain the higher risk for glaucoma in these patients. Postoperative IOP spikes should be minimized and may indicate the need for co-management with a glaucoma specialist.
Asunto(s)
Enfermedades de la Córnea , Queratoplastia Endotelial de la Lámina Limitante Posterior , Glaucoma , Humanos , Incidencia , Estudios Retrospectivos , Córnea , Enfermedades de la Córnea/epidemiología , Enfermedades de la Córnea/cirugía , Enfermedades de la Córnea/complicaciones , Queratoplastia Endotelial de la Lámina Limitante Posterior/efectos adversos , Prótesis e Implantes/efectos adversos , Glaucoma/epidemiología , Glaucoma/etiología , Glaucoma/cirugía , Queratoplastia Penetrante/efectos adversos , Factores de Riesgo , Estudios de SeguimientoRESUMEN
Descemet membrane endothelial keratoplasty (DMEK) is a partial-thickness corneal transplantation procedure that involves selective transplantation of the Descemet membrane and endothelium. DMEK offers significant advantages over other keratoplasty techniques, such as faster visual rehabilitation, better final visual acuity due to minimal optical interface effects, lower risk of allograft rejection, and less long-term dependence on topical steroids. Despite all its advantages, DMEK has been found to be more challenging than other corneal transplantation techniques, and its steep learning curve appears to be an obstacle to its widespread use and adoption by corneal surgeons worldwide. DMEK surgical training laboratories (wet labs) provide a window of opportunity for surgeons to learn, prepare, manipulate, and deliver these grafts in a risk-free environment. Wet labs are a significant learning tool, especially for those institutions that have limited tissue availability in their local centers. We provide a step-by-step guide for preparing DMEK grafts using different techniques on human and nonhuman models with instructional videos. This article should eventually help the trainees and the educators understand the requirements for performing DMEK and conducting a DMEK wet lab and develop their skills and interests from a wide variety of available techniques.
Asunto(s)
Enfermedades de la Córnea , Queratoplastia Endotelial de la Lámina Limitante Posterior , Humanos , Lámina Limitante Posterior/cirugía , Laboratorios , Queratoplastia Endotelial de la Lámina Limitante Posterior/métodos , Córnea/cirugía , Endotelio Corneal/cirugía , Enfermedades de la Córnea/cirugíaRESUMEN
To treat unilateral limbal stem cell (LSC) deficiency, we developed cultivated autologous limbal epithelial cells (CALEC) using an innovative xenobiotic-free, serum-free, antibiotic-free, two-step manufacturing process for LSC isolation and expansion onto human amniotic membrane with rigorous quality control in a good manufacturing practices facility. Limbal biopsies were used to generate CALEC constructs, and final grafts were evaluated by noninvasive scanning microscopy and tested for viability and sterility. Cultivated cells maintained epithelial cell phenotype with colony-forming and proliferative capacities. Analysis of LSC biomarkers showed preservation of "stemness." After preclinical development, a phase 1 clinical trial enrolled five patients with unilateral LSC deficiency. Four of these patients received CALEC transplants, establishing preliminary feasibility. Clinical case histories are reported, with no primary safety events. On the basis of these results, a second recruitment phase of the trial was opened to provide longer term safety and efficacy data on more patients.
Asunto(s)
Antibacterianos , Deficiencia de Células Madre Limbares , Humanos , Estudios de Factibilidad , Biopsia , Comercio , Células EpitelialesRESUMEN
PURPOSE: To describe 8 cases of reversible reticular corneal epithelial edema of the cornea that developed after use of the topical Rho-kinase inhibitor netarsudil. METHODS: This is a retrospective chart review case series of 8 patients treated with netarsudil at an academic medical center. OBSERVATIONS: Patients had predisposing corneal conditions including penetrating keratoplasty, corneal decompensation after trabeculectomy-associated endophthalmitis, congenital glaucoma with Haab striae, aphakic bullous keratopathy, history of Ahmed valve and silicone oil, and Fuchs endothelial corneal dystrophy undergoing Descemet stripping only. One patient did not have clear predisposing corneal disease other than low endothelial cell density and a history of trabeculectomy. All patients developed reticular corneal epithelial edema, which appeared as collections of moderate sized superficial epithelial bullae arranged in a reticular pattern resembling a honeycomb. Most developed these changes within weeks of initiating netarsudil, but unique to this series are 2 cases in which netarsudil was tolerated by the cornea for months before developing reticular corneal epithelial edema after diode laser cyclophotocoagulation. In cases which underwent anterior segment optical coherence tomography, the imaging demonstrated that the corneal stroma was not edematous, and the reticular corneal epithelial edema involved both host and donor corneal epithelium in cases of penetrating keratoplasty. This fully resolved in all cases upon cessation of netarsudil, and this series is the first to document resolution via a pattern in which the individual bullae become smaller and more widely spaced apart. CONCLUSION: Netarsudil can cause a reversible reticular corneal epithelial edema.