Person: Jurkunas, Ula
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Jurkunas
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Ula
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Jurkunas, Ula
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Publication Activation of mitophagy leads to decline in Mfn2 and loss of mitochondrial mass in Fuchs endothelial corneal dystrophy(Nature Publishing Group UK, 2017) Benischke, Anne-Sophie; Vasanth, Shivakumar; Miyai, Takashi; Katikireddy, Kishore Reddy; White, Tomas; Chen, Yuming; Halilovic, Adna; Price, Marianne; Price, Francis; Liton, Paloma B.; Jurkunas, UlaHuman corneal endothelial cells (HCEnCs) are terminally differentiated cells that have limited regenerative potential. The large numbers of mitochondria in HCEnCs are critical for pump and barrier function required for corneal hydration and transparency. Fuchs Endothelial Corneal Dystrophy (FECD) is a highly prevalent late-onset oxidative stress disorder characterized by progressive loss of HCEnCs. We previously reported increased mitochondrial fragmentation and reduced ATP and mtDNA copy number in FECD. Herein, carbonyl cyanide m-chlorophenyl hydrazone (CCCP)-induced mitochondrial depolarization decreased mitochondrial mass and Mfn2 levels, which were rescued with mitophagy blocker, bafilomycin, in FECD. Moreover, electron transport chain complex (I, V) decrease in FECD indicated deficient mitochondrial bioenergetics. Transmission electron microscopy of FECD tissues displayed an increased number of autophagic vacuoles containing degenerated and swollen mitochondria with cristolysis. An elevation of LC3-II and LAMP1 and downregulation of Mfn2 in mitochondrial fractions suggested that loss of fusion capacity targets fragmented mitochondria to the pre-autophagic pool and upregulates mitophagy. CCCP-induced mitochondrial fragmentation leads to Mfn2 and LC3 co-localization without activation of proteosome, suggesting a novel Mfn2 degradation pathway via mitophagy. These data indicate constitutive activation of mitophagy results in reduction of mitochondrial mass and abrogates cellular bioenergetics during degeneration of post-mitotic cells of ocular tissue.Publication UV-A Irradiation Activates Nrf2-Regulated Antioxidant Defense and Induces p53/Caspase3-Dependent Apoptosis in Corneal Endothelial Cells(The Association for Research in Vision and Ophthalmology, 2016) Liu, Cailing; Vojnovic, Dijana; Kochevar, Irene; Jurkunas, UlaPurpose To examine whether Nrf2-regulated antioxidant defense and p53 are activated in human corneal endothelial cells (CEnCs) by environmental levels of ultraviolet A (UV-A), a known stimulator of oxidative stress. Methods: Immortalized human CEnCs (HCEnCi) were exposed to UV-A fluences of 2.5, 5, 10, or 25 J/cm2, then allowed to recover for 3 to 24 hours. Control HCEnCi did not receive UV-A. Reactive oxygen species (ROS) were measured using H2DCFDA. Cell cytotoxicity was evaluated by lactate dehydrogenase (LDH) release. Levels of Nrf2, HO-1, NQO-1, p53, and caspase3 were detected by immunnoblotting or real-time PCR. Activated caspase3 was measured by immunoblotting and a fluorescence assay. Results: Exposure of HCEnCi to 5, 10, and 25 J/cm2 UV-A increased ROS levels compared with controls. Nrf2, HO-1, and NQO-1 mRNA increased 1.7- to 3.2-fold at 3 and 6 hours after irradiation with 2.5 and 5 J/cm2 UV-A. At 6 hours post irradiation, UV-A (5 J/cm2) enhanced nuclear Nrf2 translocation. At 24 hours post treatment, UV-A (5, 10, and 25 J/cm2) produced a 1.8- to 2.8-fold increase in phospho-p53 and a 2.6- to 6.0-fold increase in activated caspase3 compared with controls, resulting in 20% to 42% cell death. Conclusions: Lower fluences of UV-A induce Nrf2-regulated antioxidant defense and higher fluences activate p53 and caspase3, indicating that even near-environmental levels of UV-A may affect normal CEnCs. This data suggest that UV-A may especially damage cells deficient in antioxidant defense, and thus may be involved in the etiology of Fuchs' endothelial corneal dystrophy (FECD).Publication Screening and Characterization of Drugs That Protect Corneal Endothelial Cells Against Unfolded Protein Response and Oxidative Stress(The Association for Research in Vision and Ophthalmology, 2017) Kim, Eun Chul; Toyono, Tetsuya; Berlinicke, Cynthia A.; Zack, Donald J.; Jurkunas, Ula; Usui, Tomohiko; Jun, Albert S.Purpose To screen for and characterize compounds that protect corneal endothelial cells against unfolded protein response (UPR) and oxidative stress. Methods: Bovine corneal endothelial cells (BCECs) were treated for 48 hours with 640 compounds from a Food and Drug Administration (FDA)-approved drug library and then challenged with thapsigargin or H2O2 to induce UPR or oxidative stress, respectively. Cell viability was measured using the CellTiter-Glo survival assay. Selected “hits” were subjected to further dose-response testing, and their ability to modulate expression of UPR and oxidative stress markers was assessed by RT-PCR, Western blot, and measurement of protein carbonyl and 8-hydroxydeoxyguanosine (8-OHdG) adducts in immortalized human corneal endothelial cells (iHCECs). Results: Forty-one drugs at 20 μM and 55 drugs at 100 μM increased survival of H2O2-challenged cells, and 8 drugs at 20 μM and 2 drugs at 100 μM increased survival of thapsigargin-challenged cells, compared with untreated control cells. Nicergoline, ergothioneine, nimesulide, oxotremorine, and mefenamic acid increased survival of both H2O2- and thapsigargin-challenged cells. Oxotremorine altered DNA damage inducible 3 (CHOP) gene expression, glucose-regulated protein 78 kDa (GRP78) and activating transcription factor 4 (ATF4) protein expression, and protein carbonyl and 8-OHdG levels. Mefenamic acid altered GRP78 protein expression and protein carbonyl and 8-OHdG levels. Conclusions: Oxotremorine and mefenamic acid are potential survival factors for corneal endothelial cells under UPR and oxidative stress. The described assay can be further expanded to screen additional drugs for potential therapeutic effect in corneal endothelial diseases such as Fuchs' endothelial corneal dystrophy.Publication Anti-apoptotic gene therapy prolongs survival of corneal endothelial cells during storage(Springer Nature, 2011) Fuchsluger, T A; Jurkunas, Ula; Kazlauskas, Andrius; Dana, RezaCorneal transplantation is the most common form of grafting performed worldwide. Corneal endothelial cells (EC) form a monolayer in the posterior portion of the cornea and are essential for corneal transparency. EC loss during storage prior to transplantation is a principal reason for rendering donor tissue unsuitable for transplantation, and apoptosis has been shown to be the major contributor to EC loss during storage and after transplantation. Therefore, the potential use of anti-apoptotic gene therapy to promote both graft storage and graft survival is of major interest. The goal of this study was to transduce human donor corneas in vitro to enhance EC survival during storage conditions used in eye banking. We utilized a lentiviral vector to perform gene transfer of baculoviral p35 or mammalian Bcl-xL to corneal endothelium in different storage conditions utilizing a lentiviral vector. Our results show significantly enhanced survival and prolonged retention of physiological EC morphology in cells expressing either p35 or Bcl-xL. The clinical application of this technology could lead to a higher availability of donor tissue for transplantation, extend storage periods, and reduce graft failure after transplantation.Publication Inflammation and the Nervous System: The Connection in the Cornea in Patients with Infectious Keratitis(Association for Research in Vision and Ophthalmology (ARVO), 2011) Cruzat, Andrea; Witkin, Deborah; Baniasadi, Neda; Zheng, Lixin; Ciolino, Joseph; Jurkunas, Ula; Chodosh, James; Pavan-Langston, Deborah; Dana, Reza; Hamrah, PedramPurpose. To study the density and morphologic characteristics of epithelial dendritic cells, as correlated to subbasal corneal nerve alterations in acute infectious keratitis (IK) by in vivo confocal microscopy (IVCM). Methods. IVCM of the central cornea was performed prospectively in 53 eyes with acute bacterial (n = 23), fungal (n = 13), and Acanthamoeba (n = 17) keratitis, and in 20 normal eyes, by using laser in vivo confocal microscopy. Density and morphology of dendritic-shaped cells (DCs) of the central cornea, corneal nerve density, nerve numbers, branching, and tortuosity were assessed and correlated. It should be noted that due to the “in vivo” nature of the study, the exact identity of these DCs cannot be specified, as they could be monocytes or tissue macrophages, but most likely dendritic cells. Results. IVCM revealed the presence of central corneal DCs in all patients and controls. The mean DC density was significantly higher in patients with bacterial (441.1 ± 320.5 cells/mm2; P < 0.0001), fungal (608.9 ± 812.5 cells/mm2; P < 0.0001), and Acanthamoeba keratitis (1000.2 ± 1090.3 cells/mm2; P < 0.0001) compared with controls (49.3 ± 39.6 cells/mm2). DCs had an increased size and dendrites in patients with IK. Corneal nerves were significantly reduced in eyes with IK compared with controls across all subgroups, including nerve density (674.2 ± 976.1 vs. 3913.9 ± 507.4 μm/frame), total nerve numbers (2.7 ± 3.9 vs. 20.2 ± 3.3), main trunks (1.5 ± 2.2 vs. 6.9 ± 1.1), and branching (1.2 ± 2.0 vs. 13.5 ± 3.1; P < 0.0001). A strong association between the diminishment of corneal nerves and the increase of DC density was observed (r = −0.44; P < 0.0005). Conclusions. IVCM reveals an increased density and morphologic changes of central epithelial DCs in infectious keratitis. There is a strong and significant correlation between the increase in DC numbers and the decreased subbasal corneal nerves, suggesting a potential interaction between the immune and nervous system in the cornea.Publication Inflammation and the Nervous System: The Connection in the Cornea in Patients with Infectious Keratitis(Association for Research in Vision and Ophthalmology (ARVO), 2011) Cruzat, Andrea; Witkin, Deborah; Baniasadi, Neda; Zheng, Lixin; Ciolino, Joseph; Jurkunas, Ula; Chodosh, James; Pavan-Langston, Deborah; Dana, Reza; Hamrah, PedramPurpose.: To investigate the ability of bevacizumab to penetrate the cornea after topical application or subconjunctival injection. Methods.: Bevacizumab 1% was topically applied three times a day to the corneas of mice (BALB/c) with intact corneas (n = 14), and with corneal neovascularization (n = 14). Animals were euthanized at 1, 6, 12, and 24 hours, and 2, 4, and 7 days for immunohistochemical analyses. Donkey anti-human IgG labeled with Cy3 was used for bevacizumab immunoreactivity detection. Additionally, one-time topical bevacizumab 1% was tested in corneas with denuded epithelium (n = 16). In another group (n = 16), a single dose of 0.5 mg bevacizumab was injected subconjunctivally. Animals were euthanized at 1, 6, and 24 hours, and 2, 4, 7, 14, and 21 days for immunohistochemical studies. Results.: Bevacizumab was barely detected beyond the very superficial layer of the corneal epithelium in mice with intact corneas even after 7 days of topical administration. Application of bevacizumab in mice with corneal neovascularization; however, showed variable penetration into the corneal stroma. Experimentation with single application of topical bevacizumab in corneas with denuded epithelium or subconjunctivally injected bevacizumab showed intense staining for bevacizumab. Conclusions.: Topically applied bevacizumab has limited capacity to penetrate the corneas with intact epithelium. However, bevacizumab can penetrate the neovascularized cornea after topical application. This study demonstrates that subconjunctivally injected bevacizumab in eyes with an intact cornea penetrates well into the corneal stroma.Publication Safety and Efficacy of the Multitargeted Receptor Kinase Inhibitor Pazopanib in the Treatment of Corneal Neovascularization(Association for Research in Vision and Ophthalmology (ARVO), 2013) Amparo, Francisco; Sadrai, Zahra; Jin, Yiping; Alfonso-Bartolozzi, Belen; Wang, Haobing; Shikari, Hasanain; Ciolino, Joseph; Chodosh, James; Jurkunas, Ula; Schaumberg, Debra A.; Dana, RezaPurpose. To evaluate the safety and efficacy of topical pazopanib in the treatment of corneal neovascularization (CNV). Methods. Twenty eyes of 20 patients with stable CNV were enrolled in a prospective, open label, noncomparative study and treated with topical pazopanib 0.5% for 3 weeks, and followed for 12 weeks. The primary endpoint was to determine the tolerability and safety of topical pazopanib in the treatment of CNV defined by the occurrence of ocular and systemic adverse events during the study. The secondary endpoint was to evaluate the effect of topical pazopanib on the reduction of (1) neovascular area (NA), defined as the area of the corneal vessels themselves, (2) invasion area (IA), defined as the fraction of the total cornea into which the vessels extend, (3) vessel length (VL), defined as the mean measurement of the extent of vessels from end to end, and (4) vessel caliber (VC), defined as the mean diameter of the corneal vessels. Results. There were no severe adverse events following the use of topical pazopanib. Compared with the baseline visit, NA and VL showed a statistically significant decrease at week 3 (P = 0.02 and 0.01, respectively); and NA, IA, and VL statistically significantly decreased at week 12 (P = 0.03, 0.04, and <0.01, respectively). Visual acuity maintained without changes after the 12 week follow-up. Conclusions. This preliminary study suggests that topical treatment with pazopanib 0.5% is safe, well tolerated, and may have a role as an alternative for the treatment of CNV (ClinicalTrials.gov number, NCT01257750).Publication Topical Interleukin 1 Receptor Antagonist for Treatment of Dry Eye Disease(American Medical Association (AMA), 2013) Amparo, Francisco; Dastjerdi, Mohammad H.; Okanobo, Andre; Ferrari, Giulio; Smaga, Leila; Hamrah, Pedram; Jurkunas, Ula; Schaumberg, Debra A.; Dana, RezaImportance The immunopathogenic mechanisms of dry eye disease (DED), one of the most common ophthalmic conditions, is incompletely understood. Data from this prospective, double-masked, randomized trial demonstrate that targeting interleukin 1 (IL-1) by topical application of an IL-1 antagonist is efficacious in significantly reducing DED-related patient symptoms and corneal epitheliopathy. Objective To evaluate the safety and efficacy of treatment with the topical IL-1 receptor antagonist anakinra (Kineret; Amgen Inc) in patients having DED associated with meibomian gland dysfunction. Design and Setting Prospective phase 1/2, randomized, double-masked, vehicle-controlled clinical trial. Participants Seventy-five patients with refractory DED. Interventions Participants were randomized to receive treatment with topical anakinra, 2.5% (n=30), anakinra, 5% (n=15), or vehicle (1% carboxymethylcellulose) (n=30) 3 times daily for 12 weeks. Main Outcomes and Measures Primary outcomes were corneal fluorescein staining (CFS), complete bilateral CFS clearance, dry eye–related symptoms as measured by the Ocular Surface Disease Index, tear film breakup time, and meibomian gland secretion quality. Results Topical anakinra was well tolerated compared with vehicle, with no reports of serious adverse reactions attributable to the therapy. After 12 weeks of therapy, participants treated with anakinra, 2.5%, achieved a 46% reduction in their mean CFS score (P=.12 compared with vehicle and P<.001 compared with baseline); participants treated with anakinra, 5%, achieved a 17% reduction in their mean CFS score (P=.88 compared with vehicle and P=.33 compared with baseline); and patients treated with vehicle achieved a 19% reduction in their mean CFS score (P=.11). Complete bilateral CFS clearance was noted in 8 of 28 patients (29%) treated with anakinra, 2.5%, vs in 2of 29 patients (7%) treated with vehicle (P=.03). By week 12, treatment with anakinra, 2.5%, and treatment with anakinra, 5%, led to significant reductions in symptoms of 30% and 35%, respectively (P=.02 and P=.01, respectively, compared with vehicle); treatment with vehicle led to a 5% reduction in symptoms. Conclusions and Relevance Treatment with topical anakinra, 2.5%, for 12 weeks was safe and significantly reduced symptoms and corneal epitheliopathy in patients with DED. These data suggest that the use of an IL-1 antagonist may have a role as a novel therapeutic option for patients with DED.Publication Outcomes of phacoemulsification in patients with chronic ocular graft-versus-host disease(Springer Nature, 2015) Saboo, Ujwala S.; Amparo, Francisco; Shikari, Hasanain; Jurkunas, Ula; Dana, RezaPurpose To evaluate the outcomes of phacoemulsification in patients with ocular graft-versus-host disease (GVHD). Methods The occurrence of cataract, 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 From 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 one 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) and improved postoperatively to 0.17±0.18 (Snellen 20/29) at one 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 accounted by 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.Publication Topical Bevacizumab in the Treatment of Corneal Neovascularization(American Medical Association (AMA), 2009) Dastjerdi, Mohammad H.; Al-Arjaf, Khalid M.; Nallasamy, Nambi; Hamrah, Pedram; Jurkunas, Ula; Pineda, Roberto; Pavan-Langston, Deborah; Dana, RezaObjectives To study the safety and efficacy of topical bevacizumab in the treatment of corneal neovascularization (NV). Design In a prospective, open-label, non-comparative study, 10 eyes from 10 patients with stable corneal NV were treated with topical bevacizumab 1.0% for 3 weeks and followed up to 24 weeks. Main Outcome Measures The primary safety variables were the occurrence of ocular and systemic adverse events throughout the course of the study. The primary efficacy variables were neovascular area (NA), measuring the area of the corneal vessels themselves; vessel caliber (VC), measuring the mean diameter of the corneal vessels; and invasion area (IA), measuring the fraction of the total corneal area covered by the vessels. Results From baseline visit to the last follow-up visit, the mean reduction was 47.1% ± 36.7% for NA, 54.1% ± 28.1 for VC, and 12.2% ± 42.0% for IA. The decreases in NA and VC were statistically significant (p = 0.0014 and p = 0.00009, respectively). However, changes in IA did not achieve statistical significance (p = 0.19). Visual acuity and central corneal thickness showed no significant changes. Topical bevacizumab was well-tolerated with no adverse events. Conclusions Short-term topical bevacizumab therapy reduces the severity of corneal NV without local or systemic side-effects. Application to Clinical Practice Topical bevacizumab provides an alternative therapy in the treatment of stable corneal neovascularization.