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PURPOSE: To investigate the antifibrotic and vasoconstrictor effects of adrenaline in Schlemm's canal and suprachoroidal minimally invasive glaucoma surgery (MIGS). METHODS: Human trabecular meshwork (TM) cells were treated with different concentrations of adrenaline (0%, 0.0005%, 0.01%), and we measured the effects on contractility, cell viability and the expression of key cell cycle and fibrosis genes. Adrenaline 0.05% was also injected intracamerally in five primary open-angle glaucoma patients undergoing iStent inject or MINIject surgery combined with phacoemulsification. All patients were assessed for ocular and systemic adverse reactions, including the effects on intraoperative pupil size, preoperative and postoperative visual acuity, intraocular pressure, and anterior segment OCT results. RESULTS: Adrenaline significantly reduced the contractility of TM cells in a dose-dependent manner (87.8%, 80.6%, 7.9% matrix contraction with adrenaline 0%, 0.0005%, 0.01%, respectively). Adrenaline did not exhibit any significant cytotoxicity even at high concentrations (P > 0.05). Adrenaline 0.01% significantly downregulated the expression of key cell cycle genes in the G2 and M phases, and also decreased the expression of MRTFB and ACTA2 genes (P < 0.05). Intracameral injections of adrenaline 0.05% in the five MIGS patients did not result in any ocular or systemic adverse effects. CONCLUSION: We recommend intracameral injections of adrenaline 0.05% as a cheap and safe drug to be used before MIGS insertion. Adrenaline decreases the risk of bleeding from the trabecular meshwork and also exhibits antifibrotic effects by arresting the cell cycle, thereby increasing the postoperative success rates in MIGS. KEY MESSAGE: What is known Fibrosis is the main cause of surgical failure in minimally invasive glaucoma surgery (MIGS). Mitomycin-C and 5-fluorouracil are too toxic to be used inside the eye. What is new Adrenaline reduced the contractility of trabecular meshwork cells and inhibited the expression of key cell cycle genes and fibrosis genes, without significant cytotoxicity. Intracameral injection of adrenaline 0.05% did not result in any ocular or systemic adverse reactions in MIGS patients.
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Adrenaline is a sympathomimetic drug used to maintain pupil dilation and to decrease the risk of bleeding. The aim of this study was to demonstrate if adrenaline could exert antifibrotic effects in glaucoma surgery. Adrenaline was tested in fibroblast-populated collagen contraction assays and there was a dose-response decrease in fibroblast contractility: matrices decreased to 47.4% (P = 0.0002) and 86.6% (P = 0.0036) with adrenaline 0.0005% and 0.01%, respectively. There was no significant decrease in cell viability even at high concentrations. Human Tenon's fibroblasts were also treated with adrenaline (0%, 0.0005%, 0.01%) for 24 h and RNA-Sequencing was performed on the Illumina NextSeq 2000. We carried out detailed gene ontology, pathway, disease and drug enrichment analyses. Adrenaline 0.01% upregulated 26 G1/S and 11 S-phase genes, and downregulated 23 G2 and 17 M-phase genes (P < 0.05). Adrenaline demonstrated similar pathway enrichment to mitosis and spindle checkpoint regulation. Adrenaline 0.05% was also injected subconjunctivally during trabeculectomy, PreserFlo Microshunt and Baerveldt 350 tube surgeries, and patients did not experience any adverse effects. Adrenaline is a safe and cheap antifibrotic drug that significantly blocks key cell cycle genes when used at high concentrations. Unless contraindicated, we recommend subconjunctival injections of adrenaline (0.05%) in all glaucoma bleb-forming surgeries.
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Glaucoma , Trabeculectomia , Humanos , Glaucoma/tratamento farmacológico , Glaucoma/genética , Glaucoma/cirurgia , Epinefrina/farmacologia , Epinefrina/metabolismo , Vasoconstritores/farmacologia , Vasoconstritores/metabolismo , Genes cdc , Fibroblastos/metabolismoRESUMO
The use of RNA interference technology has proven to inhibit the expression of many target genes involved in the underlying pathogenesis of several diseases affecting various systems. First established in in vitro and later in animal studies, small interfering RNA (siRNA) and antisense oligonucleotide (ASO) therapeutics are now entering clinical trials with the potential of clinical translation to patients. Gene-silencing therapies have demonstrated promising responses in ocular disorders, predominantly due to the structure of the eye being a closed and compartmentalised organ. However, although the efficacy of such treatments has been observed in both preclinical studies and clinical trials, there are issues pertaining to the use of these drugs which require more extensive research with regards to the delivery and stability of siRNAs and ASOs. This would improve their use for long-term treatment regimens and alleviate the difficulties experienced by patients with ocular diseases. This review provides a detailed insight into the recent developments and clinical trials that have been conducted for several gene-silencing therapies, including ISTH0036, SYL040012, SYL1001, PF-04523655, Sirna-027, QR-110, QR-1123, QR-421a and IONIS-FB-LRX in glaucoma, dry eye disease, age-related macular degeneration, diabetic macular oedema and various inherited retinal diseases. Our aim is to explore the potential of these drugs whilst evaluating their associated advantages and disadvantages, and to discuss the future translation of RNA therapeutics in ophthalmology.
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Terapia Genética/métodos , Glaucoma/terapia , Degeneração Macular/terapia , Edema Macular/terapia , Oligonucleotídeos Antissenso/uso terapêutico , RNA Interferente Pequeno/uso terapêutico , Doenças Retinianas/terapia , Ensaios Clínicos como Assunto , Inativação Gênica , Humanos , Pesquisa Translacional BiomédicaRESUMO
RNAi induced by double-stranded small interfering RNA (siRNA) molecules has attracted great attention as a naturally occurring approach to silence gene expression with high specificity. The myocardin-related transcription factor/serum response factor (MRTF/SRF) pathway is a master regulator of cytoskeletal gene expression and, thus, represents a promising target to prevent fibrosis. A major hurdle to implementing siRNA therapies is the method of delivery, and we have, thus, optimized lipid-peptide-siRNA (LPR) nanoparticles containing MRTF-B siRNAs as a targeted approach to prevent conjunctival fibrosis. We tested 15 LPR nanoparticle formulations with different lipid compositions, surface charges, and targeting or non-targeting peptides in human conjunctival fibroblasts. In vitro, the LPR formulation of the DOTMA/DOPE lipid with the targeting peptide Y (LYR) was the most efficient in MRTF-B gene silencing and non-cytotoxic compared to the non-targeting formulation. In vivo, subconjunctival administration of LYR nanoparticles containing MRTF-B siRNAs doubled bleb survival in a pre-clinical rabbit model of glaucoma filtration surgery. Furthermore, MRTF-B LYR nanoparticles reduced the MRTF-B mRNA by 29.6% in rabbit conjunctival tissues, which led to significantly decreased conjunctival scarring with no adverse side effects. LYR-mediated delivery of siRNA shows promising results to increase bleb survival and to prevent conjunctival fibrosis after glaucoma filtration surgery.
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Fibrose/etiologia , Fibrose/prevenção & controle , Glaucoma/complicações , Glaucoma/genética , Nanoestruturas , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Animais , Fenômenos Biofísicos , Biópsia , Modelos Animais de Doenças , Fibroblastos/metabolismo , Cirurgia Filtrante/efeitos adversos , Cirurgia Filtrante/métodos , Inativação Gênica , Glaucoma/patologia , Glaucoma/cirurgia , Humanos , Lipossomos , Nanopartículas , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Peptídeos/química , CoelhosRESUMO
We developed an anticancer siRNA delivery system (named HLPR) through modular assembly of endogenous molecules. The structure of HLPR was a tightly condensed siRNA-peptide inner core in turn surrounded by the disordered lipid layer and thin HA coating from which the EGFR-targeted amino acid sequences of YHWYGYTPQNVI partially protrude outside of cell surfaces. Both HA and YHWYGYTPQNVI anchored on HLPR were responsible for targeting CD44 and EGFR overexpressed on the tumor cell surfaces, respectively. HLPR was relatively stable in the blood circulation and reached the tumor tissue in vivo through passive and active targeting. Then HLPR entered tumor cells mainly through EGFR-mediated pathway followed by the separation of HA from the remaining parts of nanocomplexes. The HA-uncoated complexes escaped the endosome through the membrane fusion function of DOPE and released cargoes (siRNA and peptide/siRNA) in the cytoplasm. HLPR significantly inhibited the growth of implanted subcutaneous liver tumors without toxicity.
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Carcinoma Hepatocelular/terapia , Sistemas de Liberação de Medicamentos , Receptores de Hialuronatos/antagonistas & inibidores , Neoplasias Hepáticas/terapia , Nanopartículas/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , Animais , Apoptose , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Proliferação de Células , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Humanos , Receptores de Hialuronatos/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Camundongos , Nanopartículas/química , RNA Interferente Pequeno/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Sustained drug delivery is a large unmet clinical need in glaucoma. Here, we incorporated a Myocardin-Related Transcription Factor/Serum Response Factor inhibitor, CCG-222740, into slow release large unilamellar vesicles derived from the liposomes DOTMA (1,2-di-O-octadecenyl-3-trimethylammonium propane) and DOPC (1,2-dioleoyl-sn-glycero-3-phosphocholine), and tested their effects in vitro and in vivo. RESULTS: The vesicles were spherical particles of around 130 nm and were strongly cationic. A large amount of inhibitor could be incorporated into the vesicles. We showed that the nanocarrier CCG-222740 formulation gradually released the inhibitor over 14 days using high performance liquid chromatography. Nanocarrier CCG-222740 significantly decreased ACTA2 gene expression and was not cytotoxic in human conjunctival fibroblasts. In vivo, nanocarrier CCG-222740 doubled the bleb survival from 11.0 ± 0.6 days to 22.0 ± 1.3 days (p = 0.001), decreased conjunctival scarring and did not have any local or systemic adverse effects in a rabbit model of glaucoma filtration surgery. CONCLUSIONS: Our study demonstrates proof-of-concept that a nanocarrier-based formulation efficiently achieves a sustained release of a Myocardin-Related Transcription Factor/Serum Response Factor inhibitor and prevents conjunctival fibrosis in an established rabbit model of glaucoma filtration surgery.
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Preparações de Ação Retardada/química , Sistemas de Liberação de Medicamentos , Fator de Resposta Sérica/antagonistas & inibidores , Fatores de Transcrição/antagonistas & inibidores , Animais , Doenças da Túnica Conjuntiva/tratamento farmacológico , Feminino , Fibroblastos/efeitos dos fármacos , Fibrose/tratamento farmacológico , Humanos , Lipossomos/química , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/química , Coelhos , Distribuição Tecidual , Transativadores/antagonistas & inibidores , Transativadores/químicaRESUMO
Timolol maleate (TML) is a beta-blocker drug that is commonly used to lower the intraocular pressure in glaucoma. This study focused on using a 3D printing (3DP) method for the manufacturing of an ocular, implantable, sustained-release drug delivery system (DDS). Polycaprolactone (PCL), and PCL with 5 or 10% TML implants were manufactured using a one-step 3DP process. Their physicochemical characteristics were analysed using light microscopy, scanning electronic microscopy (SEM), differential scanning calorimetry (DSC) / thermal gravimetric analysis (TGA), and Fourier-transform infrared spectroscopy (FTIR). The in vitro drug release was evaluated by UV-spectrophotometry. Finally, the effect of the implants on cell viability in human trabecular meshwork cells was assessed. All the implants showed a smooth surface. Thermal analysis demonstrated that the implants remained thermally stable at the temperatures used for the printing, and FTIR studies showed that there were no significant interactions between PCL and TML. Both concentrations (5 & 10%) of TML achieved sustained release from the implants over the 8-week study period. All implants were non-cytotoxic to human trabecular cells. This study shows proof of concept that 3DP can be used to print biocompatible and personalised ocular implantable sustained-release DDSs for the treatment of glaucoma.
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Monoclonal antibodies (mAbs) have garnered substantial attention within the field of ophthalmology and can be used to suppress scar formation after minimally invasive glaucoma surgeries. Here, by controlling mAb passive diffusion, we developed a polymeric, rate-controlling membrane reservoir loaded with poly(lactic-co-glycolic acid) microspheres to deliver mAb for several weeks. Different parameters were tested to ensure that the microspheres achieved a good quality characteristic, and our results showed that 1 %W/V emulsifier with 5 %W/V NaCl achieved mAb-loaded microspheres with the highest stability, encapsulation efficiency and minimal burst release. Then, we fabricated and compared 10 types of microporous films based on polylactic acid (PLA), polycaprolactone (PCL), and polyethylene glycol (PEG). Our results revealed distinct pore characteristics and degradation patterns in different films due to varying polymer properties, and all the polymeric film formulations showed good biocompatibility in both human trabecular meshwork cells and human conjunctival fibroblasts. Finally, the optimized microspheres were loaded into the reservoir-type polymeric implant assembled by microporous membranes with different surface coating modifications. The implant formulation, which was fabricated by 60 PCL: 40 PEG (3 %W/V) polymer with 0.1 %W/V poly(lactic-co-glycolic acid) barrier, exerted the best drug release profile that can sustained release mAb (83.6 %) for 4 weeks.
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Anticorpos Monoclonais , Glaucoma , Microesferas , Humanos , Glaucoma/cirurgia , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/química , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Poliésteres/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Polímeros/química , Polietilenoglicóis/química , Porosidade , Portadores de Fármacos/químicaRESUMO
Glaucoma is a chronic and progressive neurodegenerative disease characterized by the loss of retinal ganglion cells and visual field defects, and currently affects around 1% of the world's population. Elevated intraocular pressure (IOP) is the best-known modifiable risk factor and a key therapeutic target in hypertensive glaucoma. The trabecular meshwork (TM) is the main site of aqueous humor outflow resistance and therefore a critical regulator of IOP. Fibrosis, a reparative process characterized by the excessive deposition of extracellular matrix components and contractile myofibroblasts, can impair TM function and contribute to the pathogenesis of primary open-angle glaucoma (POAG) as well as the failure of minimally invasive glaucoma surgery (MIGS) devices. This paper provides a detailed overview of the current anti-fibrotic therapeutics targeting the TM in glaucoma, along with their anti-fibrotic mechanisms, efficacy as well as the current research progress from pre-clinical to clinical studies.
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Glaucoma de Ângulo Aberto , Glaucoma , Doenças Neurodegenerativas , Humanos , Malha Trabecular/patologia , Glaucoma de Ângulo Aberto/tratamento farmacológico , Glaucoma de Ângulo Aberto/patologia , Doenças Neurodegenerativas/patologia , Pressão Intraocular , Glaucoma/patologia , Humor AquosoRESUMO
OBJECTIVES: To develop a sustained release 5-fluorouracil (5-FU) implant by three-dimensional (3D) printing to effectively prevent conjunctival fibrosis after glaucoma surgery. METHODS: 3D-printed implants composed of polycaprolactone (PCL) and chitosan (CS) were fabricated by heat extrusion technology and loaded with 1% 5-FU. Light microscopy and scanning electron microscopy were used to study the surface morphology. The 5-FU concentration released over 8 weeks was measured by ultraviolet visible spectroscopy. The effects on cell viability, fibroblast contractility and the expression of key fibrotic genes were assessed in human conjunctival fibroblasts. KEY FINDINGS: The PCL-CS-5-FU implant sustainably released 5-FU over 8 weeks and the peak concentration was over 6.1 µg/ml during weeks 1 and 2. The implant had a smooth surface and its total weight decreased by 3.5% after 8 weeks. The PCL-CS-5-FU implant did not affect cell viability in conjunctival fibroblasts and sustainably suppressed fibroblast contractility and key fibrotic genes for 8 weeks. CONCLUSIONS: The PCL-CS-5-FU implant was biocompatible and degradable with a significant effect in suppressing fibroblast contractility. The PCL-CS-5-FU implant could be used as a sustained release drug implant, replacing the need for repeated 5-FU injections in clinic, to prevent conjunctival fibrosis after glaucoma surgery.
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Quitosana , Glaucoma , Humanos , Preparações de Ação Retardada/química , Fluoruracila/farmacologia , Quitosana/química , Impressão TridimensionalRESUMO
Lipid-based nanoparticles have recently shown great promise, establishing themselves as the gold standard in delivering novel RNA therapeutics. However, research on the effects of storage on their efficacy, safety, and stability is still lacking. Herein, the impact of storage temperature on two types of lipid-based nanocarriers, lipid nanoparticles (LNPs) and receptor-targeted nanoparticles (RTNs), loaded with either DNA or messenger RNA (mRNA), is explored and the effects of different cryoprotectants on the stability and efficacy of the formulations are investigated. The medium-term stability of the nanoparticles was evaluated by monitoring their physicochemical characteristics, entrapment and transfection efficiency, every two weeks over one month. It is demonstrated, that the use of cryoprotectants protects nanoparticles against loss of function and degradation in all storage conditions. Moreover, it is shown that the addition of sucrose enables all nanoparticles to remain stable and maintain their efficacy for up to a month when stored at -80 °C, regardless of cargo or type of nanoparticle. DNA-loaded nanoparticles also remain stable in a wider variety of storage conditions than mRNA-loaded ones. Importantly, these novel LNPs show increased GFP expression that can signify their future use in gene therapies, beyond the established role of LNPs in RNA therapeutics.
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Lipossomos , Nanopartículas , RNA Mensageiro/genética , Transfecção , DNA , Lipídeos , RNA Interferente Pequeno/genéticaRESUMO
BACKGROUND/AIMS: To evaluate the efficacy and safety of the PreserFlo MicroShunt glaucoma device in a multicentre cohort study. METHODS: All consecutive patients who received the microshunt with mitomycin-C (MMC) 0.4 mg/mL from May 2019 to September 2020 in three UK tertiary centres. Primary outcome at 1 year was a complete success, with failure defined as intraocular pressure (IOP) >21 mmHg or <20% reduction, IOP≤5 mmHg with any decreased vision on two consecutive visits, reoperation or loss of light perception vision. Secondary outcomes were IOP, best-corrected visual acuity, medications, complications, interventions and reoperations. We also performed subgroup analyses for severe glaucoma and assessed risk factors for failure. RESULTS: 104 eyes had 1-year follow-up. Complete and qualified success at 1 year were achieved in 51.9% (N=54) and 16.4% (N=17), respectively, and failure occurred in 31.7% (N=33). There was a significant reduction in IOP (mmHg) from preoperatively (23.4±0.8, N=104) to 12 months (14.7±0.6, N=104) (p<0.0001). Antiglaucoma medications also decreased from preoperatively (3.4±0.1, N=104) to 12 months (0.7±0.1, N=104) (p<0.0001). Multivariate analyses showed an association between higher mean deviation and failure (HR 1.055, 95% CI 1.0075 to 1.11, p=0.0227). Complications were hypotony (19.2%; N=20), choroidal detachments (10.6%; N=11), hyphaema (5.8%; N=6) and bleb leak (5.8%; N=6). Needling and 5-fluorouracil injections were performed in 12.5% (N=13) and 33.7% (N=35), respectively, and 11.5% (N=12) required revision surgery. CONCLUSION: The PreserFlo MicroShunt with MMC 0.4 mg/mL showed an overall success rate of 68.3% at 1 year, and led to significant IOP and medication reduction with a low rate of adverse effects.
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Glaucoma , Trabeculectomia , Humanos , Estudos de Coortes , Trabeculectomia/efeitos adversos , Glaucoma/tratamento farmacológico , Pressão Intraocular , Mitomicina/uso terapêutico , Resultado do Tratamento , Estudos RetrospectivosRESUMO
During the last decade, the fields of advanced and personalized therapeutics have been constantly evolving, utilizing novel techniques such as gene editing and RNA therapeutic approaches. However, the method of delivery and tissue specificity remain the main hurdles of these approaches. Exosomes are natural carriers of functional small RNAs and proteins, representing an area of increasing interest in the field of drug delivery. It has been demonstrated that the exosome cargo, especially miRNAs, is at least partially responsible for the therapeutic effects of exosomes. Exosomes deliver their luminal content to the recipient cells and can be used as vesicles for the therapeutic delivery of RNAs and proteins. Synthetic therapeutic drugs can also be encapsulated into exosomes as they have a hydrophilic core, which makes them suitable to carry water-soluble drugs. In addition, engineered exosomes can display a variety of surface molecules, such as peptides, to target specific cells in tissues. The exosome properties present an added advantage to the targeted delivery of therapeutics, leading to increased efficacy and minimizing the adverse side effects. Furthermore, exosomes are natural nanoparticles found in all cell types and as a result, they do not elicit an immune response when administered. Exosomes have also demonstrated decreased long-term accumulation in tissues and organs and thus carry a low risk of systemic toxicity. This review aims to discuss all the advances in exosome therapies in ophthalmology and to give insight into the challenges that would need to be overcome before exosome therapies can be translated into clinical practice.
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Exossomos , MicroRNAs , Nanopartículas , Oftalmologia , Sistemas de Liberação de Medicamentos , Exossomos/química , Exossomos/metabolismo , Humanos , MicroRNAs/metabolismoRESUMO
3D printing was invented thirty years ago. However, its application in healthcare became prominent only in recent years to provide solutions for drug delivery and clinical challenges, and is constantly evolving. This cost-efficient technique utilises biocompatible materials and is used to develop model implants to provide a greater understanding of human anatomy and diseases, and can be used for organ transplants, surgical planning and for the manufacturing of advanced drug delivery systems. In addition, 3D printed medical devices and implants can be customised for each patient to provide a more tailored treatment approach. The advantages and applications of 3D printing can be used to treat patients with different eye conditions, with advances in 3D bioprinting offering novel therapy applications in ophthalmology. The purpose of this review paper is to provide an in-depth understanding of the applications and advantages of 3D printing in treating different ocular conditions in the cornea, glaucoma, retina, lids and orbits.
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Bioimpressão , Oftalmologia , Humanos , Medicina de Precisão , Impressão Tridimensional , Próteses e ImplantesRESUMO
AIM: To determine the long-term outcomes of a cohort of complex patients with primary congenital glaucoma, aniridia and anterior segment dysgenesis. METHODS: Retrospective consecutive series between 1990-2021 in two UK tertiary centres: Guy's and St Thomas' NHS Foundation Trust and King's College Hospital NHS Foundation Trust. We recorded the number and types of surgical and laser treatments along with preoperative and postoperative data, including intraocular pressures (IOP) and anti-glaucoma medications. RESULTS: A total of 41 eyes of 21 patients were included. Primary diagnoses were primary congenital glaucoma in 16 eyes (39.0%), aniridia in 14 eyes (34.2%), and anterior segment dysgenesis in 8 eyes (19.5%). Sixteen eyes (39.0%) had one or more glaucoma surgery or laser procedures for advanced glaucoma, and the long-term follow-up was 12.8 ± 3.6 years. There was a significant decrease in postoperative IOP (mmHg) at 3 months (16.5 ± 1.6; p = 0.0067), 6 months (18.7 ± 2.1; p = 0.0386), 12 months (18.6 ± 1.7; p = 0.0229), 3 years (14.7 ± 1.2; p = 0.0126), 5 years (15.5 ± 1.8; p = 0.0330) and 10 years (15.4 ± 2.3; p = 0.7780), compared to preoperatively (24.1 ± 2.6). Surgical success (complete and qualified) was 62.5%, 50.0%, 43.8%, 46.2%, 45.5% and 28.6% at 3 months, 6 months, 12 months, 3 years, 5 years and 10 years, respectively. There was no significant change in the number of anti-glaucoma drugs postoperatively (p > 0.05). Four eyes (25.0%) had postoperative complications (hyphaema, hypotony) that resolved after conservative management. CONCLUSIONS: Surgical management of these complex eyes with advanced glaucoma is challenging. Overall, the cohort had good surgical outcomes with a significant decrease in IOP by 36.1% after long-term follow-up.
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Aniridia , Glaucoma , Trabeculectomia , Aniridia/cirurgia , Anormalidades do Olho , Seguimentos , Glaucoma/tratamento farmacológico , Humanos , Pressão Intraocular , Estudos Retrospectivos , Trabeculectomia/efeitos adversos , Resultado do Tratamento , Acuidade VisualRESUMO
The primary cause of failure for minimally invasive glaucoma surgery (MIGS) is fibrosis in the trabecular meshwork (TM) that regulates the outflow of aqueous humour, and no anti-fibrotic drug is available for intraocular use in MIGS. The myocardin-related transcription factor/serum response factor (MRTF/SRF) pathway is a promising anti-fibrotic target. This study aims to utilise a novel lipid nanoparticle (LNP) to deliver MRTF-B siRNA into human TM cells and to compare its effects with those observed in human conjunctival fibroblasts (FF). Two LNP formulations were prepared with and without the targeting peptide cΥ, and with an siRNA concentration of 50 nM. We examined the biophysical properties and encapsulation efficiencies of the LNPs, and evaluated the effects of MRTF-B silencing on cell viability, key fibrotic genes expression and cell contractility. Both LNP formulations efficiently silenced MRTF-B gene and were non-cytotoxic in TM and FF cells. The presence of cΥ made the LNPs smaller and more cationic, but had no significant effect on encapsulation efficiency. Both TM and FF cells also showed significantly reduced contractibility after transfection with MRTF-B siRNA LNPs. In TM cells, LNPs with cΥ achieved a greater decrease in contractility compared to LNPs without cΥ. In conclusion, we demonstrate that the novel CL4H6-LNPs are able to safely and effectively deliver MRTF-B siRNA into human TM cells. LNPs can serve as a promising non-viral gene therapy to prevent fibrosis in MIGS.
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The master regulator of the fibrosis cascade is the myocardin-related transcription factor/serum response factor (MRTF/SRF) pathway, making it a key target for anti-fibrotic therapeutics. In the past, inhibitors and small interfering RNAs (siRNAs) targeting the MRTF-B gene have been deployed to counter fibrosis in the eye, with the latter showing promising results. However, the biggest challenge in implementing siRNA therapeutics is the method of delivery. In this study, we utilised the novel, pH-sensitive, cationic lipid CL4H6, which has previously demonstrated potent targeting of hepatocytes and endosomal escape, to safely and efficiently deliver an MRTF-B siRNA into human conjunctival fibroblasts. We prepared two lipid nanoparticle (LNP) formulations, incorporating targeting cleavable peptide cY in one of them, and measured their physicochemical properties and silencing effect in human conjunctival fibroblasts. Both proved to be non-cytotoxic at a concentration of 50 nM and effectively silenced the MRTF-B gene in vitro, with the targeting cleavable peptide not affecting the silencing efficiency [LNP with cY: 62.1% and 81.5% versus LNP without cY: 77.7% and 80.2%, at siRNA concentrations of 50 nM (p = 0.06) and 100 nM (p = 0.09), respectively]. On the other hand, the addition of the targeting cleavable peptide significantly increased the encapsulation efficiency of the LNPs from 92.5% to 99.3% (p = 0.0005). In a 3D fibroblast-populated collagen matrix model, both LNP formulations significantly decreased fibroblast contraction after a single transfection. We conclude that the novel PEGylated CL4H6-MRTF-B siRNA-loaded LNPs represent a promising therapeutic approach to prevent conjunctival fibrosis after glaucoma filtration surgery.
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PURPOSE: High intensity focused ultrasound (HiFU) is a cyclodestructive therapy for controlling intraocular pressure (IOP) in glaucoma. The mechanism of action is thought to be through destruction of the ciliary epithelium as well as increased uveoscleral outflow. We reviewed the change in aqueous humour dynamics parameters including aqueous humour flow rate, tonographic outflow facility (TOF) and uveoscleral outflow at 12 months. PATIENTS AND METHODS: This is a prospective observational study. Consecutive patients with open angle glaucoma (OAG) or ocular hypertension (OHT) requiring further IOP lowering were enroled in the study between August 2016 and January 2017. Patients were commenced on medication washout period prior to baseline and twelve months' visit. RESULTS: Sixteen patients (OAG) in the treatment group underwent assessment at twelve months follow up. Mean age was 63.1 ± 11 years. Eleven patients were African/Caribbean and 5 were Caucasian. Nine patients were female and 7 were male. Mean post-washout IOP was reduced by 21% (28.3 ± 5.7 at baseline vs 22.4 ± 8.4 mmHg at 12 months, p = 0.04). Aqueous humour flow rate was reduced by 16% at twelve months (2.40 ± 0.6 at baseline vs 2.02 ± 0.6 µl/min at 12 months, p = 0.0493). There was no statistically significant change in the TOF (0.12 ± 0.09 at baseline vs 0.08 ± 0.05 µl/min/mmHg at 12 months, p = 0.08) or uveoscleral outflow (0.6 ± 1.3 at baseline vs 1.3 ± 0.85 µl/min at 12 months, p = 0.15). CONCLUSION: In this study, we demonstrated that the observed IOP reduction was likely due to aqueous humour flow rate reduction. The TOF and uveoscleral outflow were not detectibly changed.
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Glaucoma de Ângulo Aberto , Hipertensão Ocular , Idoso , Humor Aquoso , Feminino , Glaucoma de Ângulo Aberto/cirurgia , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Hipertensão Ocular/terapia , Tonometria OcularRESUMO
1. NAME OF THE DISEASE (SYNONYMS): Primary congenital glaucoma (PCG). Glaucoma, congenital (GLC). 2. OMIM# OF THE DISEASE: 231300- GLC3A. 600975- GLC3B. 613085- GLC3C. 613086- GLC3D. 617272- GLC3E. 3. NAME OF THE ANALYSED GENES OR DNA/CHROMOSOME SEGMENTS: CYP1B1. LTBP2. MYOC. FOXC1. TEK. 4. OMIM# OF THE GENE(S): CYP1B1 MIM# 601771. LTBP2 MIM# 602091. MYOC MIM# 601652. FOXC1 MIM# 601090. TEK MIM# 600221. Review of the analytical and clinical validity, as well as of the clinical utility of DNA-based testing for variants in the CYP1B1, LTBP2 and MYOC gene(s) in â diagnostic, â predictive and â prenatal settings and for â risk assessment in relatives.