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1.
Int J Mol Sci ; 23(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36077314

RESUMO

We report herein on the effects of all-trans retinoic acid (ATRA) on two-dimensional (2D) and three-dimensional (3D) cultures of human trabecular meshwork (HTM) cells that were treated with transforming growth factor ß2 (TGF-ß2). In the presence of 5 ng/mL TGF-ß2, the effects of ATRA on the following were observed: (1) the barrier function of the 2D HTM monolayers, as determined by trans-endothelial electrical resistance (TEER) and fluorescein isothiocyanate (FITC) dextran permeability measurements; (2) a Seahorse cellular bio-metabolism analysis; (3) physical properties, including the size and stiffness, of 3D spheroids; (4) the gene expression of extracellular matrix (ECM) molecules, ECM modulators including tissue inhibitor of metalloproteinases (TIMPs), matrix metalloproteinases (MMPs), tight junction (TJ)-related molecules, and endoplasmic reticulum (ER)-stress-related factors. ATRA significantly inhibited the TGF-ß2-induced increase in the TEER values and FITC dextran permeability of the 2D monolayers, while an ATRA monotreatment induced similar effects as TGF-ß2. A real-time metabolic analysis revealed that ATRA significantly inhibited the TGF-ß2-induced shift in metabolic reserve from mitochondrial oxidative phosphorylation to glycolysis in 2D HTM cells, whereas ATRA alone did not induce significant metabolic changes. In contrast, ATRA induced the formation of substantially downsized and softer 3D spheroids in the absence and presence of TGF-ß2. The different effects induced by ATRA toward 2D and 3D HTM cells were also supported by the qPCR analysis of several proteins as above. The findings reported here indicate that ATRA may induce synergistic and beneficial effects on TGF-ß2-treated 2D- and 3D-cultured HTM cells; those effects varied significantly between the 2D and 3D cultures.


Assuntos
Glaucoma , Malha Trabecular , Técnicas de Cultura de Células em Três Dimensões , Células Cultivadas , Glaucoma/metabolismo , Humanos , Malha Trabecular/metabolismo , Fator de Crescimento Transformador beta2/metabolismo , Fator de Crescimento Transformador beta2/farmacologia , Tretinoína/metabolismo , Tretinoína/farmacologia
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 3963-3966, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36086118

RESUMO

Glaucoma is the leading cause of irreversible blindness worldwide. Currently, the only treatable risk factor for glaucoma is elevated intraocular pressure (IOP). Glaucoma is commonly caused due to a decreased permeability of the trabecular meshwork, a porous structure at the eye outlet. This prevents the effective outflow of aqueous humour, increasing IOP. This study aims to simulate both normal and glaucomatous conditions of aqueous humour flow in the eye via computational fluid dynamics (CFD). Using clinical data, an idealised geometrical model of the eye was created. Darcy's law was employed to calculate the permeability values for various IOPs, which was then applied to the CFD model. Subsequently, verifiable and validated models for a normal and glaucomatous eye were achieved. Clinical Relevance- Glaucoma surgical treatments are often met with post-operative complications due to an insufficient or even excessive outflow of aqueous humour. The resulting glaucomatous eye model from this study can be used to test how different glaucoma filtration surgeries affect the efficacy of aqueous humour outflow. In turn, the most effective glaucoma surgical procedure may be identified for specific eye geometries according to race, age, gender, etc.


Assuntos
Humor Aquoso , Glaucoma , Glaucoma/diagnóstico , Glaucoma/cirurgia , Humanos , Hidrodinâmica , Pressão Intraocular , Malha Trabecular
3.
Cells ; 11(15)2022 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-35954296

RESUMO

Glycocalyx morphology was examined in the trabecular outflow pathway of monkey eyes with and without experimental glaucoma. Laser burns were administered along ~270 degrees of the trabecular meshwork (TM) of one eye (n = 6) or both eyes (n = 2) of each monkey until intraocular pressure remained elevated. Portions of the TM were not laser-treated. Unlasered eyes (n = 6) served as controls. Enucleated eyes were perfused at 15 mmHg to measure the outflow facility, perfused with fluorescein to evaluate the outflow pattern, perfusion-fixed for glycocalyx labeling, and processed for electron microscopy. Coverage and thickness of the glycocalyx were measured in the TM, Schlemm's canal (SC), collector channels (CCs), intrascleral veins (ISVs), and episcleral veins (ESVs) in non-lasered regions and high- and low-flow regions of controls. Compared to controls, laser-treated eyes had decreased outflow facility (p = 0.02). Glycocalyx thickness increased from the TM to ESVs in non-lasered regions and controls (p < 0.05). Glycocalyx coverage was generally greater distally in non-lasered regions (p < 0.05). In lasered regions, TM, SC, and CCs were partly to completely obliterated, and ISVs and ESVs displayed minimal glycocalyx. Whether the glycocalyx is decreased in the trabecular outflow pathway of human glaucomatous eyes warrants investigation.


Assuntos
Humor Aquoso , Glaucoma , Animais , Humor Aquoso/metabolismo , Glaucoma/metabolismo , Glicocálix/metabolismo , Haplorrinos , Humanos , Malha Trabecular/metabolismo
4.
Genes (Basel) ; 13(8)2022 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-36011411

RESUMO

Increased trabecular meshwork (TM) cell and tissue contractility is a driver of the reduced outflow facility and elevation of intraocular pressure (IOP) associated with primary open-angle glaucoma (POAG). Connective tissue growth factor (CTGF) is an established mediator of TM cell contractility, and its expression is increased in POAG due to transforming growth factor ß 2 (TGFß2) signalling. Inhibiting CTGF upregulation using microRNA (miRNA) mimetics could represent a new treatment option for POAG. A combination of in silico predictive tools and a literature review identified a panel of putative CTGF-targeting miRNAs. Treatment of primary human TM cells with 5 ng/mL TGFß2 for 24 h identified miR-18a-5p as a consistent responder, being upregulated in cells from five different human donors. Transfection of primary donor TM cells with 20 nM synthetic miR-18a-5p mimic reduced TGFß2-induced CTGF protein expression, and stable lentiviral-mediated overexpression of this miRNA reduced TGFß2-induced contraction of collagen gels. Together, these findings identify miR-18a-5p as a mediator of the TGFß2 response and a candidate therapeutic agent for glaucoma via its ability to inhibit CTGF-associated increased TM contractility.


Assuntos
Glaucoma de Ângulo Aberto , MicroRNAs , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Glaucoma de Ângulo Aberto/genética , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Malha Trabecular/metabolismo , Fator de Crescimento Transformador beta2/genética , Fator de Crescimento Transformador beta2/farmacologia
5.
ACS Biomater Sci Eng ; 8(9): 3899-3911, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-35984428

RESUMO

The permeability of the human trabecular meshwork (HTM) regulates eye pressure via a porosity gradient across its thickness modulated by stacked layers of matrix fibrils and cells. Changes in HTM porosity are associated with increases in intraocular pressure and the progress of diseases such as glaucoma. Engineered HTMs could help to understand the structure-function relation in natural tissues and lead to new regenerative solutions. Here, melt electrowriting (MEW) is explored as a biofabrication technique to produce fibrillar, porous scaffolds that mimic the multilayer, gradient structure of native HTM. Poly(caprolactone) constructs with a height of 125-500 µm and fiber diameters of 10-12 µm are printed. Scaffolds with a tensile modulus between 5.6 and 13 MPa and a static compression modulus in the range of 6-360 kPa are obtained by varying the scaffold design, that is, the density and orientation of the fibers and number of stacked layers. Primary HTM cells attach to the scaffolds, proliferate, and form a confluent layer within 8-14 days, depending on the scaffold design. High cell viability and cell morphology close to that in the native tissue are observed. The present work demonstrates the utility of MEW for reconstructing complex morphological features of natural tissues.


Assuntos
Engenharia Tecidual , Tecidos Suporte , Humanos , Porosidade , Engenharia Tecidual/métodos , Tecidos Suporte/química , Malha Trabecular/fisiologia
6.
BMC Genom Data ; 23(1): 67, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-36002796

RESUMO

PURPOSE: Primary open-angle glaucoma (POAG) continues to be a poorly understood disease. Although there were multiple researches on the identification of POAG biomarkers, few studies systematically revealed the immune-related cells and immune infiltration of POAG. Bioinformatics analyses of optic nerve (ON) and trabecular meshwork (TM) gene expression data were performed to further elucidate the immune-related genes of POAG and identify candidate target genes for treatment. METHODS: We performed a gene analysis of publicly available microarray data, namely, the GSE27276-GPL2507, GSE2378-GPL8300, GSE9944-GPL8300, and GSE9944-GPL571 datasets from the Gene Expression Omnibus database. The obtained datasets were used as input for parallel pathway analyses. Based on random forest and support vector machine (SVM) analysis to screen the key genes, significantly changed pathways were clustered into functional categories, and the results were further investigated. CIBERSORT was used to evaluate the infiltration of immune cells in POAG tissues. A network visualizing the differences between the data in the POAG and normal groups was created. GO and KEGG enrichment analyses were performed using the Metascape database. We divided the differentially expressed mRNAs into upregulated and downregulated groups and predicted the drug targets of the differentially expressed genes through the Connectivity Map (CMap) database. RESULTS: A total of 49 differentially expressed genes, including 19 downregulated genes and 30 upregulated genes, were detected. Five genes ((Keratin 14) KRT14, (Hemoglobin subunit beta) HBB, (Acyl-CoA Oxidase 2) ACOX2, (Hephaestin) HEPH and Keratin 13 (KRT13)) were significantly changed. The results showed that the expression profiles of drug disturbances, including those for avrainvillamide-analysis-3, cytochalasin-D, NPI-2358, oxymethylone and vinorelbine, were negatively correlated with the expression profiles of disease disturbances. This finding indicated that these drugs may reduce or even reverse the POAG disease state. CONCLUSION: This study provides an overview of the processes involved in the molecular pathogenesis of POAG in the ON and TM. The findings provide a new understanding of the molecular mechanism of POAG from the perspective of immunology.


Assuntos
Glaucoma de Ângulo Aberto , Biologia Computacional/métodos , Glaucoma de Ângulo Aberto/diagnóstico , Humanos , Análise em Microsséries , RNA Mensageiro/metabolismo , Malha Trabecular/metabolismo
7.
Curr Protoc ; 2(8): e528, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36005888

RESUMO

Glaucoma, a progressive neurodegenerative ocular disease, is the leading cause of irreversible blindness worldwide. Elevated intraocular pressure (IOP) is the most common-and the only treatable-risk factor for glaucoma. IOP is generated by the balance between production and removal of aqueous humor in the anterior part of the eye, and the latter happens either through the uveoscleral or the conventional pathway. Although both pathways are important for aqueous humor removal, dysfunction within the conventional pathway is more commonly associated with increased resistance leading to elevated IOP and glaucoma. The conventional pathway can be separated into proximal (trabecular meshwork and inner wall of Schlemm's canal) and distal (outer wall of Schlemm's canal, collector channels, and episcleral vasculature) regions. Both regions contribute resistance to aqueous humor removal, but the proximal region has been studied more extensively due to the availability of model systems. In contrast, little is known about the role of the distal region in outflow resistance, largely due to the lack of suitable in vitro models. To address this, we have developed a novel method of isolating and culturing vascular distal outflow pathway (VDOP) cells from the distal outflow region of human eyes. VDOP cells can be used to study the physiological and molecular functions of cells in the distal outflow region and can help in the development of ocular hypotensive drugs that specifically target this area. We also provide a protocol describing immunohistochemical methods to validate the molecular profile of these cells, utilizing cell surface markers that distinguish them from adjacent cells. © 2022 Wiley Periodicals LLC. Basic Protocol 1: Isolation and culture of VDOP cells Basic Protocol 2: Analysis of cell surface markers.


Assuntos
Glaucoma , Pressão Intraocular , Humor Aquoso/metabolismo , Glaucoma/metabolismo , Humanos , Esclera/metabolismo , Malha Trabecular/metabolismo
8.
Biotechnol Bioeng ; 119(10): 2698-2714, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35836364

RESUMO

Glaucoma is the leading cause of irreversible blindness worldwide and is characterized by the progressive degeneration of the optic nerve. Intraocular pressure (IOP), which is considered to be the main risk factor for glaucoma development, builds up in response to the resistance (resistance to what?) provided by the trabecular meshwork (TM) to aqueous humor (AH) outflow. Although the TM and its relationship to AH outflow have remained at the forefront of scientific interest, researchers remain uncertain regarding which mechanisms drive the deterioration of the TM. Current tissue-engineering fabrication techniques have come up with promising approaches to successfully recreate the TM. Nonetheless, more accurate models are needed to understand the factors that make glaucoma arise. In this review, we provide a chronological evaluation of the technological milestones that have taken place in the field of glaucoma research, and we conduct a comprehensive comparison of available TM fabrication technologies. Additionally, we also discuss AH perfusion platforms, since they are essential for the validation of these scaffolds, as well as pressure-outflow relationship studies and the discovery of new IOP-reduction therapies.


Assuntos
Glaucoma , Malha Trabecular , Humor Aquoso , Humanos , Pressão Intraocular , Malha Trabecular/fisiologia
9.
Adv Ther ; 39(9): 4076-4093, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35790641

RESUMO

INTRODUCTION: We report 2-year outcomes after implantation of iStent trabecular micro-bypass stent with phacoemulsification, in Japanese patients with mild-moderate open-angle glaucoma (OAG). METHODS: This was a 24-month, prospective, longitudinal, observational, post-marketing study conducted between July 2017 and September 2020. Patients consisted of adults with OAG on antiglaucoma medications who had cataract surgery combined with one iStent implantation. Outcome measures included intraocular pressure (IOP), antiglaucoma medications, treatment success rates (defined as eyes having lower IOP with same or reduced number of medications from baseline, or same IOP with reduced number of medications from baseline, and not requiring secondary glaucoma surgeries postoperatively), and safety. Outcomes were analyzed in the overall cohort and in glaucoma subtypes: primary OAG, normal-tension glaucoma, and exfoliative glaucoma. RESULTS: Overall, 232 eyes were enrolled. At 24 months, mean ± standard deviation IOP decreased from 17.6 ± 4.0 mmHg preoperatively to 14.3 ± 3.0 mmHg (p < 0.05), and mean number of medications reduced from 2.2 ± 1.2 preoperatively to 0.7 ± 1.2 (p < 0.05). Similar trends were observed across glaucoma subtypes. In the overall cohort, 96.7%, 95.3%, and 93.7% of patients achieved treatment success at 6, 12, and 24 months, respectively. There were 67.6% medication-free eyes at 24 months compared to 3.2% medication-free eyes preoperatively (p < 0.0001). Safety profile was favorable over the 2-year period. CONCLUSIONS: Following iStent implantation with phacoemulsification, clinically relevant and statistically significant reductions in IOP and number of medications were observed in Japanese eyes with OAG over 2 years, with favorable safety profile. These reductions were observed across all glaucoma subtypes.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Facoemulsificação , Adulto , Glaucoma/cirurgia , Glaucoma de Ângulo Aberto/tratamento farmacológico , Glaucoma de Ângulo Aberto/cirurgia , Humanos , Pressão Intraocular , Japão , Marketing , Vigilância de Produtos Comercializados , Estudos Prospectivos , Stents , Malha Trabecular/cirurgia
10.
Histochem Cell Biol ; 158(3): 253-260, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35829814

RESUMO

Megapinosomes are endocytic organelles found in human macrophage colony-stimulating factor (M-CSF) monocyte-derived M macrophages. They are large (several microns) and have a complex internal structure that is connected with the cytosol and consists of interconnected knots and concave bridges with sizes in the range of 100 nm. We called this structure trabecular meshwork. The luminal part of the megapinosome can be connected with luminal tubules and cisterns that form the megapinosome complex. The structures are especially well visible in scanning electron tomography when macrophages are prepared by high-pressure freezing and freeze substitution. Our research received a new impulse after studying the literature on hematopoietic cells, where very similar, most likely homologous, structures have been published in peritoneal macrophages as well as in megakaryocytes and blood platelets. In platelets, they serve as membrane storage that is used for structural changes of platelets during activation.


Assuntos
Endocitose , Macrófagos , Megacariócitos , Humanos , Malha Trabecular
12.
Int J Mol Sci ; 23(13)2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35806375

RESUMO

Elevated intraocular pressure (IOP) is a major risk factor for glaucoma that results from impeded fluid drainage. The increase in outflow resistance is caused by trabecular meshwork (TM) cell dysfunction and excessive extracellular matrix (ECM) deposition. Baicalein (Ba) is a natural flavonoid and has been shown to regulate cell contraction, fluid secretion, and ECM remodeling in various cell types, suggesting the potential significance of regulating outflow resistance and IOP. We demonstrated that Ba significantly lowered the IOP by about 5 mmHg in living mice. Consistent with that, Ba increased the outflow facility by up to 90% in enucleated mouse eyes. The effects of Ba on cell volume regulation and contractility were examined in primary human TM (hTM) cells. We found that Ba (1-100 µM) had no effect on cell volume under iso-osmotic conditions but inhibited the regulatory volume decrease (RVD) by up to 70% under hypotonic challenge. In addition, Ba relaxed hTM cells via reduced myosin light chain (MLC) phosphorylation. Using iTRAQ-based quantitative proteomics, 47 proteins were significantly regulated in hTM cells after a 3-h Ba treatment. Ba significantly increased the expression of cathepsin B by 1.51-fold and downregulated the expression of D-dopachrome decarboxylase and pre-B-cell leukemia transcription factor-interacting protein 1 with a fold-change of 0.58 and 0.40, respectively. We suggest that a Ba-mediated increase in outflow facility is triggered by cell relaxation via MLC phosphorylation along with inhibiting RVD in hTM cells. The Ba-mediated changes in protein expression support the notion of altered ECM homeostasis, potentially contributing to a reduction of outflow resistance and thereby IOP.


Assuntos
Oftalmopatias , Flavanonas , Animais , Humor Aquoso/metabolismo , Oftalmopatias/metabolismo , Flavanonas/metabolismo , Flavanonas/farmacologia , Pressão Intraocular , Camundongos , Cadeias Leves de Miosina/metabolismo , Malha Trabecular/metabolismo
13.
Int J Mol Sci ; 23(13)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35805889

RESUMO

Glaucoma is a multifactorial disease leading to irreversible blindness. Primary open-angle glaucoma (POAG) is the most common form and is associated with the elevation of intraocular pressure (IOP). Reduced aqueous humor (AH) outflow due to trabecular meshwork (TM) dysfunction is responsible for IOP elevation in POAG. Extracellular matrix (ECM) accumulation, actin cytoskeletal reorganization, and stiffening of the TM are associated with increased outflow resistance. Transforming growth factor (TGF) ß2, a profibrotic cytokine, is known to play an important role in the development of ocular hypertension (OHT) in POAG. An appropriate mouse model is critical in understanding the underlying molecular mechanism of TGFß2-induced OHT. To achieve this, TM can be targeted with recombinant viral vectors to express a gene of interest. Lentiviruses (LV) are known for their tropism towards TM with stable transgene expression and low immunogenicity. We, therefore, developed a novel mouse model of IOP elevation using LV gene transfer of active human TGFß2 in the TM. We developed an LV vector-encoding active hTGFß2C226,228S under the control of a cytomegalovirus (CMV) promoter. Adult C57BL/6J mice were injected intravitreally with LV expressing null or hTGFß2C226,228S. We observed a significant increase in IOP 3 weeks post-injection compared to control eyes with an average delta change of 3.3 mmHg. IOP stayed elevated up to 7 weeks post-injection, which correlated with a significant drop in the AH outflow facility (40.36%). Increased expression of active TGFß2 was observed in both AH and anterior segment samples of injected mice. The morphological assessment of the mouse TM region via hematoxylin and eosin (H&E) staining and direct ophthalmoscopy examination revealed no visible signs of inflammation or other ocular abnormalities in the injected eyes. Furthermore, transduction of primary human TM cells with LV_hTGFß2C226,228S exhibited alterations in actin cytoskeleton structures, including the formation of F-actin stress fibers and crossed-linked actin networks (CLANs), which are signature arrangements of actin cytoskeleton observed in the stiffer fibrotic-like TM. Our study demonstrated a mouse model of sustained IOP elevation via lentiviral gene delivery of active hTGFß2C226,228S that induces TM dysfunction and outflow resistance.


Assuntos
Glaucoma de Ângulo Aberto , Hipertensão Ocular , Actinas/metabolismo , Animais , Humor Aquoso/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Glaucoma de Ângulo Aberto/genética , Glaucoma de Ângulo Aberto/metabolismo , Pressão Intraocular , Camundongos , Camundongos Endogâmicos C57BL , Hipertensão Ocular/genética , Hipertensão Ocular/metabolismo , Malha Trabecular/metabolismo , Fator de Crescimento Transformador beta2/metabolismo
14.
PLoS One ; 17(7): e0271171, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35816482

RESUMO

Among increasing eye diseases, glaucoma may hurt the optic nerves and lead to vision loss, the treatment of which is to reduce intraocular pressure (IOP). In this research, we introduce a new concept of the surgery simulator for Minimally Invasive Glaucoma Surgery (MIGS). The concept is comprised of an anterior eye model and a fluidic circulatory system. The model made of flexible material includes a channel like the Schlemm's canal (SC) and a membrane like the trabecular meshwork (TM) covering the SC. The system can monitor IOP in the model by a pressure sensor. In one of the MIGS procedures, the TM is cleaved to reduce the IOP. Using the simulator, ophthalmologists can practice the procedure and measure the IOP. First, considering the characteristics of human eyes, we defined requirements and target performances for the simulator. Next, we designed and manufactured the prototype. Using the prototype, we measured the IOP change before and after cleaving the TM. Finally, we demonstrated the availability by comparing experimental results and target performances. This simulator is also expected to be used for evaluations and developments of new MIGS instruments and ophthalmic surgery robots in addition to the surgical training of ophthalmologists.


Assuntos
Glaucoma , Próteses Visuais , Glaucoma/cirurgia , Humanos , Pressão Intraocular , Microfluídica , Malha Trabecular/fisiologia
15.
J Glaucoma ; 31(8): e49-e68, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35701875

RESUMO

PRCIS: A literature review of selective laser trabeculoplasty (SLT) energy dose-response found no definitive relationship between intraocular pressure (IOP) reduction with respect to total or pulse energy, race, pigmentation, or application pattern. PURPOSE: SLT is a safe and effective treatment for lowering IOP. Although evidence is mounting for the advantage of its use as a first-line treatment for IOP reduction, the SLT procedures in use vary widely. The purpose of this literature review was to investigate whether there were any relationships between SLT energy and efficacy for lowering IOP in the published literature. METHODS: A literature review was undertaken that included studies in which energy levels required for successful SLT treatment were investigated: in general, with respect to angle pigmentation, race or ethnicity, and treatment arc extent. RESULTS: There was no indication that higher (or lower) energy used in the treatment leads to greater (or less) IOP reduction. Similar results were obtained regarding the level of trabecular meshwork pigmentation. Race was not found to be associated with altered dose response in SLT. There were indications that treating the full 360 degrees, as opposed to smaller arcs, could be beneficial for more IOP reduction. IOP reduction from SLT was found to be similar to that provided by topical medications. CONCLUSIONS: The optimal energy level of SLT needed for IOP reduction has not yet been definitively established, with all reported pulse energies resulting in similar IOP reduction. Furthermore, similar lack of conclusive findings exists regarding optimal SLT energy dosage for use in different races and degrees of trabecular meshwork pigmentation. This parameter and each of the abovementioned factors requires further research.


Assuntos
Glaucoma de Ângulo Aberto , Terapia a Laser , Hipotensão Ocular , Trabeculectomia , Glaucoma de Ângulo Aberto/tratamento farmacológico , Glaucoma de Ângulo Aberto/cirurgia , Humanos , Pressão Intraocular , Terapia a Laser/métodos , Lasers , Hipotensão Ocular/cirurgia , Malha Trabecular/cirurgia , Trabeculectomia/métodos , Resultado do Tratamento
16.
Sci Rep ; 12(1): 9564, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35689009

RESUMO

Glaucoma is a complex neurodegenerative disease resulting in progressive optic neuropathy and is a leading cause of irreversible blindness worldwide. Primary open angle glaucoma (POAG) is the predominant form affecting 65.5 million people globally. Despite the prevalence of POAG and the identification of over 120 glaucoma related genetic loci, the underlaying molecular mechanisms are still poorly understood. The transforming growth factor beta (TGF-ß) signalling pathway is implicated in the molecular pathology of POAG. To gain a better understanding of the role TGF-ß2 plays in the glaucomatous changes to the molecular pathology in the trabecular meshwork, we employed RNA-Seq to delineate the TGF-ß2 induced changes in the transcriptome of normal primary human trabecular meshwork cells (HTM). We identified a significant number of differentially expressed genes and associated pathways that contribute to the pathogenesis of POAG. The differentially expressed genes were predominantly enriched in ECM regulation, TGF-ß signalling, proliferation/apoptosis, inflammation/wound healing, MAPK signalling, oxidative stress and RHO signalling. Canonical pathway analysis confirmed the enrichment of RhoA signalling, inflammatory-related processes, ECM and cytoskeletal organisation in HTM cells in response to TGF-ß2. We also identified novel genes and pathways that were affected after TGF-ß2 treatment in the HTM, suggesting additional pathways are activated, including Nrf2, PI3K-Akt, MAPK and HIPPO signalling pathways. The identification and characterisation of TGF-ß2 dependent differentially expressed genes and pathways in HTM cells is essential to understand the patho-physiology of glaucoma and to develop new therapeutic agents.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Doenças Neurodegenerativas , Células Cultivadas , Perfilação da Expressão Gênica , Glaucoma/patologia , Glaucoma de Ângulo Aberto/tratamento farmacológico , Humanos , Doenças Neurodegenerativas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Malha Trabecular/metabolismo , Fator de Crescimento Transformador beta2/metabolismo
17.
Sci Rep ; 12(1): 10535, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35732689

RESUMO

The intraocular pressure (IOP)-lowering mechanisms of micropulse laser trabeculoplasty (MLT) remain unclear. The present study was performed to investigate the mechanism of action of MLT, and to determine whether the pigmentation intensity of trabecular meshwork (TM) cells is associated with the treatment effects. Primary human TM cells were exposed to melanin granules to artificially introduce different levels of pigmentation. Micropulse (MP) laser irradiation was performed, and interleukin (IL)-1α/ß, matrix metalloproteinases (MMPs), tissue inhibitor of metalloproteinases (TIMPs), and extracellular matrix (ECM) protein expression were evaluated by RT-qPCR and immunocytochemistry. IL-1α/ß and MMP-1, -3, and -9 mRNA expression were significantly upregulated at 4 and 24 h after MP laser irradiation, respectively, but there were no significant changes in TIMP expression. The extent of these upregulation was greater in cells with strong pigmentation intensity. Protein expressions of fibronectin and collagen I were significantly decreased in cells with strong staining intensity. These results suggested that MP laser irradiation alter the MMP/TIMP ratio and enhance ECM turnover, resulting in increased outflow of aqueous humor. The pigmentation intensity of the TM tissues may affect the treatment efficacy of MLT, because TM cells with strong staining intensity showed a significantly enhanced response to MP laser irradiation.


Assuntos
Malha Trabecular , Trabeculectomia , Células Cultivadas , Proteínas da Matriz Extracelular/metabolismo , Humanos , Pressão Intraocular , Lasers , Metaloproteinases da Matriz/genética , Metaloproteinases da Matriz/metabolismo , Pigmentação , Inibidores Teciduais de Metaloproteinases/genética , Malha Trabecular/metabolismo
18.
Sci Rep ; 12(1): 10584, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35732782

RESUMO

We investigated whether trabeculopuncture (TP) could detect distal outflow resistance to predict the outcome of canal-based glaucoma surgery such as ab interno trabeculectomy (AIT). These procedures have a high utilization in open angle glaucoma, but fail in eyes with an unidentified distal outflow resistance. We assigned 81 porcine eyes to two groups: trial (n = 42) and control (n = 39). At 24 h, four YAG-laser trabeculopunctures were placed nasally, followed by a 180° AIT at the same site at 48 h. The proportion of TP responders between both AIT groups was compared. Histology and outflow canalograms were determined. Both post-TP and post-AIT IOPs were lower than baseline IOP (p = 0.015 and p < 0.01, respectively). The success rates of TP and AIT were 69% and 85.7%, respectively. Sensitivity and specificity values of TP as predictive test for AIT success were 77.7% and 83.3%, respectively. The positive and negative predictive values were 96.6% and 38.5%, respectively. We conclude that a 10% reduction in IOP after TP can be used as a predictor for the success (> 20% IOP decrease) of 180° AIT in porcine eyes.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Trabeculectomia , Animais , Glaucoma/diagnóstico , Glaucoma/cirurgia , Glaucoma de Ângulo Aberto/cirurgia , Pressão Intraocular , Suínos , Malha Trabecular/cirurgia , Trabeculectomia/métodos , Resultado do Tratamento
19.
Invest Ophthalmol Vis Sci ; 63(6): 2, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35648639

RESUMO

Purpose: To characterize the distribution of pigment particles in aqueous drainage structures of DBA/2J mice with different intraocular pressure (IOP) levels. Methods: DBA/2J mice were monitored from 9 to 44 weeks of age. IOP measurements were performed periodically. At 12, 20, 28, and 36 weeks, three mice were randomly selected for each time point and divided into three IOP groups. The morphology, size, and quantity of pigment particles in aqueous drainage structures were determined via transmission electron microscopy combined with ImageJ-based analysis. Between-group differences were evaluated with a one-way analysis of variance and Fisher's least significant difference test. Results: In the anterior chamber, 74.2% (187/252) of pigment particles were round (diameter range, 0.20-0.73 µm), and 25.8% (65/252) were oval (length range, 0.35-1.20 µm ). In the high-IOP group (IOP≥15 mmHg), pigment particles in the trabecular meshwork (TM) were more abundant and larger in size than those in the normal-IOP group (P<0.001). All separate pigment particles in the TM of the high-IOP group were >0.4  µm in size. The diameters of round (IOP≤10 mmHg, 0.44±0.13 µm; IOP between 10 and 15 mmHg, 0.57±0.13 µm; IOP≥15 mmHg, 0.61±0.12 µm) and the lengths of oval (0.65±0.14 µm vs. 0.77±0.12 µm vs. 0.88±0.15 µm, respectively) pigment particles in the TM differed among groups (F=27.258 and F=27.295, respectively; both P<0.001). No such differences were discovered in the iris and around Schlemm's canal (P>0.05). Conclusions: In DBA/2J mice, large and medium pigment particles (>0.4 µm) seem to play an important role in causing aqueous outflow obstruction and IOP elevation.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Animais , Modelos Animais de Doenças , Pressão Intraocular , Camundongos , Camundongos Endogâmicos DBA , Tonometria Ocular , Malha Trabecular
20.
Comput Methods Programs Biomed ; 221: 106922, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35660940

RESUMO

BACKGROUND AND OBJECTIVE: Intraocular pressure (IOP) is determined by aqueous humor outflow resistance, which is a function of the combined resistance of Schlemm's canal (SC) endothelium and the trabecular meshwork (TM) and their interactions in the juxtacanalicular connective tissue (JCT) region. Aqueous outflow in the conventional outflow pathway results in pressure gradient across the TM, JCT, and SC inner wall, and induces mechanical stresses and strains that influence the geometry and homeostasis of the outflow system. The outflow resistance is affected by alteration in tissues' geometry, so there is potential for active, two-way, fluid-structure interaction (FSI) coupling between the aqueous humor (fluid) and the TM, JCT, and SC inner wall (structure). However, our understanding of the biomechanical interactions of the aqueous humor with the outflow connective tissues and its contribution to the outflow resistance regulation is incomplete. METHODS: In this study, a microstructural finite element (FE) model of a human eye TM, JCT, and SC inner wall was constructed from a segmented, high-resolution histologic 3D reconstruction of the human outflow system. Three different elastic moduli (0.004, 0.128, and 51.5 MPa based on prior reports) were assigned to the TM/JCT complex while the elastic modulus of the SC inner wall was kept constant at 0.00748 MPa. The hydraulic conductivity was programmed separately for the TM, JCT, and SC inner wall using a custom subroutine. Cable elements were embedded into the TM and JCT extracellular matrix to represent the directional stiffness imparted by anisotropic collagen fibril orientation. The resultant stresses and strains in the outflow system were calculated using fluid-structure interaction method. RESULTS: The higher TM/JCT stiffness resulted in larger stresses, but smaller strains in the outflow connective tissues, and resulted in a 4- and 5-fold larger pressure drop across the SC inner wall, respectively, compared to the most compliant model. Funneling through µm-sized SC endothelial pores was evident in the models at lower tissue stiffness, but aqueous flow was more turbulent in models with higher TM/JCT stiffness. CONCLUSIONS: The mechanical properties of the outflow tissues play a crucial role in the hydrodynamics of the aqueous humor in the conventional outflow system.


Assuntos
Humor Aquoso , Malha Trabecular , Humor Aquoso/metabolismo , Fenômenos Biomecânicos , Humanos , Hidrodinâmica , Pressão Intraocular , Malha Trabecular/metabolismo
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