Matrix metalloproteinase-2, tissue inhibitor of matrix metalloproteinase-2, and transforming growth factor beta 1 in the aqueous humor and serum of patients with pseudoexfoliation syndrome

The impact of matrix metalloproteinases and their tissue inhibitors in patients with chronic glaucoma - a literature review

Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) play an important role in the pathophysiology of chronic glaucoma, as they are involved in extracellular matrix (ECM) remodeling in the trabecular meshwork (TM), affecting its ability to efficiently regulate intraocular pressure (IOP). Ensuring the balance between MMPs and TIMPs helps to maintain homeostasis in ocular tissues, which is essential to avoid glaucomatous lesions. Elevated levels of MMPs and increased degradation of the ECM, ultimately affecting aqueous humor outflow and increasing IOP, characterize glaucoma. In the current literature review, the impact and interactions of MMPs and TIMPs in chronic glaucoma have been emphasized, with multiple but still unelucidated roles in the mentioned pathology including their clinical implications, future research directions, and therapeutic approaches. Research to date indicates that the expression of TIMPs is altered in patients with chronic glaucoma, suggesting a compensatory response to increased MMPs activity. Certain drugs can influence the expression levels of MMPs and TIMPs, therefore therapeutic strategies can be developed to restore the balance between tissue enzymes and their inhibitors. Therefore, understanding the relationship between MMPs and TIMPs is a key factor in the pathogenesis of chronic glaucoma. Understanding the interplay between the two provides interesting insights into ECM remodeling in ocular tissues, highlighting the potential of targeted therapies to restore the balance between proteolytic enzymes and their inhibitors.

Transforming growth factor-β receptors: versatile mechanisms of ligand activation

Transforming growth factor-β (TGF-β) signaling is initiated by activation of transmembrane TGF-β receptors (TGFBR), which deploys Smad2/3 transcription factors to control cellular responses. Failure or dysregulation in the TGF-β signaling pathways leads to pathological conditions. TGF-β signaling is regulated at different levels along the pathways and begins with the liberation of TGF-β ligand from its latent form. The mechanisms of TGFBR activation display selectivity to cell types, agonists, and TGF-β isoforms, enabling precise control of TGF-β signals. In addition, the cell surface compartments used to release active TGF-β are surprisingly vibrant, using thrombospondins, integrins, matrix metalloproteinases and reactive oxygen species. The scope of TGFBR activation is further unfolded with the discovery of TGFBR activation initiated by other signaling pathways. The unique combination of mechanisms works in series to trigger TGFBR activation, which can be explored as therapeutic targets. This comprehensive review provides valuable insights into the diverse mechanisms underpinning TGFBR activation, shedding light on potential avenues for therapeutic exploration.

The TGFβ Induced MicroRNAome of the Trabecular Meshwork

Primary open-angle glaucoma (POAG) is a progressive optic neuropathy with a complex, multifactorial aetiology. Raised intraocular pressure (IOP) is the most important clinically modifiable risk factor for POAG. All current pharmacological agents target aqueous humour dynamics to lower IOP. Newer therapeutic agents are required as some patients with POAG show a limited therapeutic response or develop ocular and systemic side effects to topical medication. Elevated IOP in POAG results from cellular and molecular changes in the trabecular meshwork driven by increased levels of transforming growth factor β (TGFβ) in the anterior segment of the eye. Understanding how TGFβ affects both the structural and functional changes in the outflow pathway and IOP is required to develop new glaucoma therapies that target the molecular pathology in the trabecular meshwork. In this study, we evaluated the effects of TGF-β1 and -β2 treatment on miRNA expression in cultured human primary trabecular meshwork cells. Our findings are presented in terms of specific miRNAs (miRNA-centric), but given miRNAs work in networks to control cellular pathways and processes, a pathway-centric view of miRNA action is also reported. Evaluating TGFβ-responsive miRNA expression in trabecular meshwork cells will further our understanding of the important pathways and changes involved in the pathogenesis of glaucoma and could lead to the development of miRNAs as new therapeutic modalities in glaucoma.

TGF-β Isoforms and Local Environments Greatly Modulate Biological Nature of Human Retinal Pigment Epithelium Cells

To characterize transforming growth factor-β (TGF-β) isoform (TGF-β1~3)-b's biological effects on the human retinal pigment epithelium (RPE) under normoxia and hypoxia conditions, ARPE19 cells cultured by 2D (two-dimensional) and 3D (three-dimensional) conditions were subjected to various analyses, including (1) an analysis of barrier function by trans-epithelial electrical resistance (TEER) measurements; (2) qPCR analysis of major ECM molecules including collagen 1 (COL1), COL4, and COL6; α-smooth muscle actin (αSMA); hypoxia-inducible factor 1α (HIF1α); and peroxisome proliferator-activated receptor-gamma coactivator (PGC1α), a master regulator for mitochondrial respiration;, tight junction-related molecules, Zonula occludens-1 (ZO1) and E-cadherin; and vascular endothelial growth factor (VEGF); (3) physical property measurements of 3D spheroids; and (4) cellular metabolic analysis. Diverse effects among TGF-β isoforms were observed, and those effects were also different between normoxia and hypoxia conditions: (1) TGF-β1 and TGF-β3 caused a marked increase in TEER values, and TGF-β2 caused a substantial increase in TEER values under normoxia conditions and hypoxia conditions, respectively; (2) the results of qPCR analysis supported data obtained by TEER; (3) 3D spheroid sizes were decreased by TGF-β isoforms, among which TGF-β1 had the most potent effect under both oxygen conditions; (4) 3D spheroid stiffness was increased by TGF-β2 and TGF-β3 or by TGF-β1 and TGF-β3 under normoxia conditions and hypoxia conditions, respectively; and (5) the TGF-β isoform altered mitochondrial and glycolytic functions differently under oxygen conditions and/or culture conditions. These collective findings indicate that the TGF-β-induced biological effects of 2D and 3D cultures of ARPE19 cells were substantially diverse depending on the three TGF-β isoforms and oxygen levels, suggesting that pathological conditions including epithelial-mesenchymal transition (EMT) of the RPE may be exclusively modulated by both factors.

TGF-β-3 Induces Different Effects from TGF-β-1 and -2 on Cellular Metabolism and the Spatial Properties of the Human Trabecular Meshwork Cells

To compare the effects among three TGF-β isoforms (TGF-β-1, TGF-β-2, and TGF-β-3) on the human trabecular meshwork (HTM), two-dimensional (2D) and three-dimensional (3D) cultures of commercially available certified immortalized HTM cells were used, and the following analyses were conducted: (1) trans-endothelial electrical resistance (TEER) and FITC dextran permeability measurements (2D); (2) a real-time cellular metabolic analysis (2D); (3) analysis of the physical property of the 3D HTM spheroids; and (4) an assessment of the gene expression levels of extracellular matrix (ECM) components (2D and 3D). All three TGF-β isoforms induced a significant increase in TEER values and a relative decrease in FITC dextran permeability in the 2D-cultured HTM cells, but these effects were the most potent in the case of TGF-β-3. The findings indicated that solutions containing 10 ng/mL of TGF-β-1, 5 ng/mL of TGF-β-2, and 1 ng/mL of TGF-β-3 had nearly comparable effects on TEER measurements. However, a real-time cellular metabolic analysis of the 2D-cultured HTM cells under these concentrations revealed that TGF-3-β induced quite different effects on the metabolic phenotype, with a decreased ATP-linked respiration, increased proton leakage, and decreased glycolytic capacity compared with TGF-β-1 and TGF-β-2. In addition, the concentrations of the three TGF-β isoforms also caused diverse effects on the physical properties of 3D HTM spheroids and the mRNA expression of ECMs and their modulators, in many of which, the effects of TGF-β-3 were markedly different from TGF-β-1 and TGF-β-2. The findings presented herein suggest that these diverse efficacies among the TGF-β isoforms, especially the unique action of TGF-β-3 toward HTM, may induce different effects within the pathogenesis of glaucoma.

Sarcopenia using pectoralis muscle area and lymphocyte-to-monocyte ratio (LMR) are independent prognostic factors in patients for nonmetastatic breast cancer

Sarcopenia is defined as loss of skeletal muscle mass and strength. This can lead to adverse clinical outcomes in patients with advanced cancer. The lymphocyte-to-monocyte ratio (LMR), a converted inflammatory response, is associated with poor prognosis in patients with malignancies. Herein, we examined the prognostic influence of sarcopenia status assessed by pectoralis muscle area (PMA), inflammatory status calculated by LMR, and its association with disease-free survival (DFS) in a cohort of women diagnosed with nonmetastatic breast cancer. A total of 293 patients with nonmetastatic breast cancer who underwent primary mass resection and radiotherapy between January 2011 and December 2017 were enrolled. The cross-sectional area of the muscle (cm2) at PMA was measured using computed tomography before radiation therapy. Baseline monocyte and lymphocyte counts were obtained from the complete blood count to calculate the LMR. Most of the patients (248/293, 84.6%) underwent breast conservation surgery. Lymph node involvement at diagnosis (hazard ratio [HR], 5.08; P < .001), low LMR (HR, 2.79; P = .007), and low PMA (HR, 3.80; P < .001) were independent poor prognostic factors in multivariate analysis. The mean DFS of sarcopenic and nonsarcopenic patients was 89.8 months and 118.8 months, respectively (P < .001). Sarcopenic patients with low LMR showed the worst outcomes, whereas nonsarcopenic patients with high LMR showed the best outcomes. Low PMA and low LMR were independent poor prognostic factors for DFS in patients with nonmetastatic breast cancer.

Primary Human Trabecular Meshwork Model for Pseudoexfoliation

The lack of an animal model or an in vitro model limits experimental options for studying temporal molecular events in pseudoexfoliation syndrome (PXF), an age related fibrillopathy causing trabecular meshwork damage and glaucoma. Our goal was to create a workable in vitro model of PXF using primary human TM (HTM) cell lines simulating human disease. Primary HTM cells harvested from healthy donors (n = 3), were exposed to various concentrations (5 ng/mL, 10 ng/mL, 15 ng/mL) of transforming growth factor-beta1 (TGF-β1) for different time points. Morphological change of epithelial–mesenchymal transition (EMT) was analyzed by direct microscopic visualization and immunoblotting for EMT markers. Expression of pro-fibrotic markers were analyzed by quantitative RT-PCR and immunoblotting. Cell viability and death in treated cells was analyzed using FACS and MTT assay. Protein complex and amyloid aggregate formation was analyzed by Immunofluorescence of oligomer11 and amyloid beta fibrils. Effect of these changes with pharmacological inhibitors of canonical and non-canonical TGF pathway was done to analyze the pathway involved. The expression of pro-fibrotic markers was markedly upregulated at 10 ng/mL of TGF-β1 exposure at 48–72 h of exposure with associated EMT changes at the same time point. Protein aggregates were seen maximally at these time points that were found to be localized around the nucleus and in the extracellular matrix (ECM). EMT and pro-fibrotic expression was differentially regulated by different canonical and non-canonical pathways suggesting complex regulatory mechanisms. This in vitro model using HTM cells simulated the main characteristics of human disease in PXF like pro-fibrotic gene expression, EMT, and aggregate formation.

Decorin, Tenascin C, Total Antioxidant, and Total Oxidant Level Changes in Patients with Pseudoexfoliation Syndrome

PURPOSE

Pseudoexfoliation syndrome (PEX) is an eye disease that develops under the influence of regional population differences, genetic factors, age, and environmental factors and is characterized by visualization of a gray-white fibrogranular substance in the lens anterior capsule and/or pupil margin during anterior segment examination. The underlying biochemical mechanisms of the disease have not yet been fully elucidated. Therefore, this study was designed to show the changes in aqueous humor and blood serum levels of matrix metalloproteinases (decorin and tenascin C), total antioxidants (TAS), and total oxidants (TOS) in both cataract patients who have unilateral PEX material and cataract patients who do not have unilateral PEX material.

METHODS

Biological samples were simultaneously collected from 22 cataract patients who had unilateral pseudoexfoliation (PEX patients) and 22 cataract patients who did not have unilateral pseudoexfoliation (control patients). From the collected biological samples, decorin (DEC) and tenascin C (TN-C) were measured with the enzyme-linked immunosorbent assay (ELISA) method, and TAS and TOS were measured with an autoanalyzer.

RESULTS

When decorin, tenascin C, and TOS values of PEX patients were compared with those of control patients, there was a statistically significant increase in all three parameters. Conversely, TAS values showed a statistically significant decrease in PEX patients compared to controls. DEC, TN-C, TAS values, and TOS values were significantly higher in aqueous fluid than in blood in both the PEX patient and control groups.

CONCLUSIONS

We suggest that parameters such as DEC, TN-C, TAS, and TOS play a role in the etiopathology of pseudoexfoliation syndrome. Thus, bringing these increased levels of extracellular proteins and TOS and decreased levels of TAS back to within physiological limits can mediate the reorganization of the blood-aqueous fluid barrier and slow the progression of pseudoexfoliation syndrome.

Serum insulin-like growth factor-1 levels in patients with pseudoexfoliation syndrome and glaucoma

Insulin-like growth factor-1 (IGF-1) is altered in several neurodegenerative diseases, the association between serum IGF-1 levels and glaucoma has not been evaluated. This study was designed to evaluate whether serum IGF-1 levels are different in patients with Pseudoexfoliation (PEX) with or without glaucoma. The study was conducted with 110 participants aged 65 years or older who were divided into three groups: group 1, patients with PEX syndrome; group 2, patients with PEX glaucoma; and group 3, participants without PEX or glaucoma. All participants underwent full ophthalmological examination and a detailed medical history was recorded. Patients with known neurodegenerative diseases other than PEX glaucoma were excluded. Serum IGF-1 levels were measured by automated chemiluminescent assay. Groups 1, 2, and 3 included 35, 34, and 41 patients, respectively; there were no differences regarding age, gender, or systemic disease status. There were also no statistically significant differences between the groups in terms of IGF-1 levels, which were 91.7 ± 39.1, 101.1 ± 40.2, and 107.2 ± 43.8 ng/ml for groups 1, 2, and 3, respectively (p = 0.276). Serum IGF-1 levels were similar by gender, the presence of systemic disease, status of diabetes mellitus, and laterality of the PEX material. There was no correlation between the cup-to-disk ratios and IGF-1 levels (r = -0.214, p = 0.223). IGF-1 levels in the circulation did not differ in the presence of PEX syndrome with or without glaucoma. This may indicate that the neurodegenerative process is local rather than systemic.

Metalloproteinase 9 and TIMP-1 expression in retina and optic nerve in absolute angle closure glaucoma

PURPOSE

Glaucoma is one of the most important reason causes of the blindness, associated with retinal ganglion cells (RGC) death. This process is not fully understood, however apoptosis due to hypoxia is one of the most important processes leading to RGC death. Glaucomatous optic neuropathy is characterized by remodeling of the extracellular matrix due to metalloproteinase activation, which leads to loss of RGC and axons at the optic nerve head. The aim of the study was to evaluate metalloproteinase 9 (MMP-9) and tissue metalloproteinase inhibitor-1 (TIMP-1) expression in the retinal ganglion cells and optic nerve axons in 33 eyes with absolute primary glaucoma.

MATERIAL/METHODS

To evaluate MMP-9 and TIMP-1 expression primary polyclonal goat antibodies against MMP-9 and TIMP-1 were used. The control group was composed of 8 cases of eyes enucleated and fixed in the first day after trauma.

RESULTS

MMP-9 expression was observed in retinal ganglion cells and in the inner nuclear layer of the retina in all the examined cases. In 28 out of 33 glaucomatous eyes, MMP-9 expression was observed in the proliferating glial cells surrounding the optic nerve axons. TIMP-1 expression was observed in 10 out of 33 glaucomatous eyes, only in retinal ganglion cells. None of the examined injured eyes showed MMP-9 and TIMP-1 expression.

CONCLUSIONS

MMP-9 activation rather than TIMP-1 may by associated with the pathomechanism of retinal ganglion cell and optic nerve damage in absolute glaucoma.

Influence of lymphatic endothelial cells on proliferation and invasiveness of esophageal carcinoma cells in vitro and lymphangiogenesis in vivo

The aim of the study was to investigate the interaction between esophageal carcinoma cells with different differentiation degree and esophageal carcinoma-related lymphatic endothelial cells. Different lymphatic endothelial cell conditioned mediums were used to cultivate well-differentiated esophageal carcinoma EC9706 cells and poorly differentiated esophageal carcinoma KYSE150 cells, and immunocytochemistry and Western blot analyses were applied to detect the expression of MMP-9 protein and TIMP-2 protein in each group; in situ hybridization and RT-PCR methods were used to detect the expression of MMP-9 and TIMP-2 mRNA in each group; CCK-8 method was used to detect cell proliferation in each group; and transwell method was utilized to detect cell invasiveness in each group. Through constructing the transplanted tumor model of esophageal carcinoma of nude mice, the D2-40 and LYVE-1 immunohistochemical staining was performed on transplanted tumors and surrounding tissues, lymphatic microvessels were marked, and lymphatic microvessel density (LMVD) was measured. The expression of MMP-9 protein and mRNA in experimental group was significantly higher than that in control groups (P < 0.05); TIMP-2 protein and mRNA expression in experimental group was significantly lower than that in control groups (P < 0.05); cell proliferation ability and invasiveness ability in experimental group were significantly higher than those in control groups (P < 0.05); LMVD-marked D2-40 and LMVD-marked LYVE-1 of transplanted tumor tissue in the experimental group were significantly higher than those in control groups (P < 0.05). The esophageal squamous carcinoma-related lymphatic microvessel could promote the proliferation and invasive ability of esophageal squamous carcinoma cells in vitro. It had different effects on esophageal carcinoma cells with different differentiation degree and had more obvious influence on poorly differentiated esophageal carcinoma cells, which may be related to the up-regulated MMP-2 expression and down-regulated TIMP-2 expression of esophageal carcinoma cells. The esophageal squamous carcinoma-related lymphatic microvessel endothelial cells could promote the growth of esophageal carcinoma-transplanted tumor of nude mice and lymphangiogenesis.

Transforming Growth Factor Beta 3 Modifies Mechanics and Composition of Extracellular Matrix Deposited by Human Trabecular Meshwork Cells

Pseudoexfoliation syndrome is a systemic disorder of the extracellular matrix (ECM) with ocular manifestations in the form of chronic open angle glaucoma. Elevated levels of TGFβ3 in the aqueous humor of individuals with pseudoexfoliation glaucoma (PEX) have been reported. The influence of TGFβ3 on the biochemical composition and biomechanics of ECM of human trabecular meshwork (HTM) cells was investigated. HTM cells from eye bank donor eyes were isolated, plated on aminosilane functionalized glass substrates and cultured in the presence or absence of 1 ng/mL TGFβ3 for 4 weeks. After incubation, samples were decellularized and decellularization was verified by immunostaining. The mechanics of the remaining ECM that was deposited by the treated or the control cells were measured by atomic force microscopy (AFM). Imaged by AFM, the surface features of the ECM from both sets of samples had a similar roughness/topography (as determined by RMS values) suggesting surface features of the ECM were similar in both cases; however, the ECM from the HTM cells treated with TGFβ3 was between 3- and 5-fold stiffer than that produced by the control HTM cells. Proteins present in the ECM were solubilized and analyzed using liquid chromatography tandem mass spectroscopy (LC-MS/MS). Data indicate that multiple proteins previously reported to be altered in glaucoma were changed in the ECM as a result of the presence of TGFβ3, including inhibitors of the BMP and Wnt signaling pathways. Gremlin1and 4, SERPINE1 and 2, periostin, secreted frizzled related protein (SFRP) 1 and 4, and ANGPTL4 were among those proteins that were overexpressed in the ECM after TGFβ3 treatment.