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PubMed2005

Molecular mechanism of bovine trabecular meshwork cells apoptosis induced by dexamethasone and protection by pilocarpine.

PURPOSE: To study the molecular mechanism of trabecular meshwork cells apoptosis induced by dexamethasone and the protection of pilocarpine. METHODS: Determining mRNA expression with reverse transcription-polymerase chain protein expression with Western blots and the percentage of reaction (RT-PCR), apoptotic cells with fluorescent microscopy. RESULTS: Dexamethasone up-regulated Fas proteins and affected Bax, caspase-8 and caspase-9 proteins in an action of first decrease then increase. Pre -treatment with pilocarpine decreased the four proteins expression, which were increased by dexamethasone. Pilocarpine self could decrease pro-apoptotic factors Bax, caspase-8 and caspase-9 proteins expression. CONCLUSION: Fas/FasL pathway participated in apoptotic process induced by dexamethasone in trabecular meshwork cells and the process was probably related with both caspase-8 and caspase-9 pathways. Pilocarpine protected the cells against apoptosis through down-regulating Fas, Bax, caspase-8 and caspase-9 proteins expression.

Animals↗
PubMed1991

Age-related changes of microfibrils in the cornea and trabecular meshwork of the human eye.

Microfibrils in the connective tissue can be subdivided into two classes, elastin-associated and elastin-independent microfibrils. The distribution of microfibrils of both classes were studied in the anterior segment of the human ocular tissues, with a view to examine age-related morphological changes. In the trabecular meshwork of infants, the tubular structure of microfibrils was identified and the fibrils were associated with elastin, forming a typical elastic fiber. This was confirmed by the tannic acid-uranyl acetate staining which reacts specifically with elastin. In the cornea, microfibrils were detected in the deep stroma of the infant. They were not associated with elastin (elastin-independent microfibrils). In the glaucomatous eye of a 7-year-old boy, microfibrils were indistinct in the trabecular meshwork. In the corneal stroma of the same eye, microfibrils were observed, but the occurrence was rarer than in the nonglaucomatous infants examined in this study. In the trabecular meshwork of aged persons, no tubular or fibrillar structure was seen around the elastin. Microfibrils were not observed in the cornea. The morphological features and occurrence of microfibrils change with age in the anterior segment of the human eye. Thus microfibrils can be a good indicator for the age-related changes in these tissues.

Actin Cytoskeleton↗
PubMed2025

Investigating the miRNA-mRNA interactome of human trabecular meshwork cells treated with TGF-β1 provides insights into the pathogenesis of pseudoexfoliation glaucoma.

Pseudoexfoliation glaucoma is a severe form of secondary open angle glaucoma and is associated with activation of the TGF-β pathway by TGF-β1. MicroRNAs (miRNAs) are small non-coding RNA species that are involved in regulation of mRNA expression and translation. To investigate what glaucomatous changes occur in the trabecular meshwork and how these changes may be regulated by miRNAs, we performed a bioinformatics analysis resulting in a miRNA-mRNA interactome. Primary human trabecular meshwork cells originating from normal donors were treated with TGF-β1 at 5 ng/mL for 24h; total RNA was extracted followed by RNA-Seq and miRNA-Seq. For both mRNA and miRNA species, differential expression was determined using a bioinformatics pipeline consisting of FastQC, STAR, FeatureCounts, edgeR (for miRNA) and DESeq2 (for mRNA). Putative mRNA-miRNA interactions between differentially expressed mRNA and miRNA species were determined using interaction databases miRWalk, miRTarBase, TarBase and TargetScan. To classify mRNA species by function and pathway, gene enrichment was performed using Enrichr. The resulting miRNA-mRNA interactome consisted of 1202 interactions. Some highly connected microRNAs were hsa-let-7e-5p, hsa-miR-20a-5p, hsa-miR-122-5p, and hsa-miR-29c-3p. Most differentially expressed genes were indicated to be regulated by miRNAs. The sub-interactomes of genes involved in specific pseudoexfoliation glaucoma related enrichment terms such as oxidative stress, unfolded protein response, signal molecules and ECM remodelling were determined. This is the first study to present a genome-wide microRNA-mRNA regulatory network for human trabecular meshwork cells treated with TGF-β1 and may serve to generate unbiased hypotheses about regulatory functions and mRNA targets of miRNAs in pseudoexfoliation glaucoma and may help to develop miRNA-based therapeutics.

Humans↗
PubMed1985

The resistance of the trabecular meshwork to aqueous humor outflow.

A theoretical model is presented that is able to explain for the first time the pressure drop across the trabecular meshwork. The ramified flow paths in the subendothelial region of the trabecular meshwork can be interpreted as a filter bed. Data from transmission electron microscope (TEM) photographs are the starting point of the theoretical consideration. Taking shrinkage of the sections into account, the pressure gradient across the subendothelial region amounts to 0.05 mm Hg. As these canaliculi are coated by a film of glycosaminoglycans (GAGs), the pressure drop is presumably a function of the film thickness. Only film thicknesses of 0.35 micron led to pressure gradients in the experimentally verified magnitude. As the whole filter bed probably does not contribute to the filtration but only about 10%, the pressure drop specified is reached when the GAG coating is 0.25 micron. As these values seem to be fairly realistic, it can be concluded that the subendothelial region of the juxtacanalicular meshwork (about 2 micron thickness) can be regarded as the "locus generis" of aqueous humor outflow resistance.

Aqueous Humor↗
PubMed2001

Stromelysin gene transfer into cultured human trabecular cells and rat trabecular meshwork in vivo.

PURPOSE: To determine whether stromelysin gene can be introduced into and expressed in the cultured human trabecular cells as well as in the rat eye in vivo through means of a recombinant replication-deficient adenovirus. METHODS: Stromelysin cDNA was obtained by reverse transcription-polymerase chain reaction with mRNA extracted from the cultured human trabecular cells after induction with interleukin 1alpha. Adenovirus vector that contains stromelysin cDNA was constructed by cotransfection of pJM17 and pDeltaA.CMV-str into the 293 cells. The expression of stromelysin in the cultured human trabecular cells was assayed by Western blot and zymography. The expression of stromelysin in the trabecular meshwork of the rat eyes was detected by in situ hybridization and immunohistochemistry. RESULTS: The constructed adenovirus vector contained stromelysin cDNA, but no E1 region. Western blot and zymogram revealed that the stromelysin could be expressed and that it possessed enzymatic activity in cultured human trabecular cells. In situ hybridization and immunostaining of the stromelysin showed that the complete form of stromelysin was expressed in the trabecular meshwork, the iris, and the uveoscleral outflow pathway of the rat eye. CONCLUSIONS: Stromelysin, a functional gene, can be transferred in vivo into rat eyes and in vitro into cultured human trabecular cells using a replication-deficient adenovirus vector. This shows the possibility of gene therapy in glaucoma.

Adenoviridae↗
PubMed1988

Effects of agonists on the intracellular cyclic AMP concentration in monkey trabecular meshwork cells.

We examined the effects of several neuroendocrine agents on the intracellular cyclic AMP level in cultured monkey trabecular meshwork cells. Among the peptide agonists studied, only the vasoactive intestinal peptide elevated the cyclic AMP level. Alpha-melanocyte stimulating hormone, glucagon, and others showed no stimulation. Prostaglandin E1 and L-isoproterenol also enhanced the intracellular cyclic AMP level. Such effects may implicate physiologic roles of these agonists in the trabecular meshwork.

Animals↗
PubMed2005

Primary trabecular meshwork cells incubated in human aqueous humor differ from cells incubated in serum supplements.

PURPOSE: To determine whether aqueous humor, the in vivo source of nutrients for trabecular meshwork cells, alters cellular and molecular characteristics in primary trabecular monolayer cell cultures when compared with standard culture conditions. METHODS: Human primary trabecular meshwork cell cultures were grown in DMEM supplemented with 50% human aqueous humor (DMEM-AH), heat-denatured DMEM-AH, 10% fetal bovine serum (DMEM-FBS, the standard culture supplement), or heat-denatured DMEM-FBS. Confluent trabecular cells were assayed for cell propagation and morphology for 21 days. Protein expression profiles of trabecular cell lysates were analyzed by two-dimensional polyacrylamide gel electrophoresis. Western blot analysis was used to determine the protein expression of myocilin and TIMP-1 in conditioned media collected from trabecular cells at 5, 10, 15, and 21 days. Myocilin expression was also analyzed by Western immunoblots after addition of dexamethasone (10(-7) M) or ascorbic acid (29 mg/dL). RESULTS: Trabecular cells supplemented with DMEM-AH for 21 days showed decreased cell proliferation when compared with DMEM-FBS (11% vs. 141%). Cellular morphology was also altered: Trabecular cells incubated in DMEM-AH showed larger-, broader-, and flatter-appearing cells than did the more spindle-shaped cells grown in DMEM-FBS. Protein profiles of trabecular cell lysates isolated from cells incubated in DMEM-AH differed from those incubated in DMEM-FBS. In DMEM-AH-conditioned medium, myocilin expression was increased and TIMP-1 expression was decreased at day 21. Induction of myocilin by dexamethasone was observed in conditioned medium isolated from cells treated with DMEM-FBS (442%), but only a 10% increase in myocilin was observed beyond the normal induction in DMEM-AH. Daily administration of ascorbic acid to DMEM-AH failed to increase myocilin expression beyond that obtained with DMEM-AH. CONCLUSIONS: Addition of human aqueous humor rather than FBS to trabecular monolayer cell cultures triggers significant changes in cellular and molecular characteristics. The protein component of aqueous humor is responsible for these changes. Aqueous humor supplementation may maintain cultured trabecular cells in a more physiologic state.

Adult↗
PubMed1986

Thermal effects on the trabecular meshwork induced by laser irradiation: clinical implications deduced from ultrastructural studies on the macaca speciosa monkey.

The pressure lowering effect brought about by irradiating the chamber angle with argon laser light according to Wise and Witter was studied by ultrastructural methods and was analysed in order to ascertain the mechanism responsible. To this end, the effects induced in 4 macaca speciosa monkeys by such irradiation were examined using scanning and transmission electron microscopy. It was noted that the phenomena observed depend critically on the precise location of the irradiation site. When the anterior trabecular meshwork is irradiated, a proliferation of monocellular, atypical corneal endothelium cells occurs which tightly surround the irradiation location. In irradiation of the posterior trabecular meshwork, however, this effect is much less prominent. In both cases, by the end of the twelfth week a progressive, lytic degeneration of the entire trabecular meshwork was observed which reached the inner wall of Schlemm's canal.

Animals↗
PubMed1997

Cellular pharmacology and molecular biology of the trabecular meshwork inducible glucocorticoid response gene product.

Studies of the effects of glucocorticoid (GC) and oxidative stress stimuli in differentiated cultures of human trabecular meshwork (HTM) cells have provided the rationale for our studies of a major new gene termed TIGR (trabecular meshwork inducible GC response). The TIGR clone was isolated by differential library screening using selection criteria based on the induction pattern of a new protein/glycoprotein found in HTM cultures after prolonged but not brief exposure to GCs. This GC induction pattern matched the time course and dose response required for intraocular pressure elevation in patients receiving corticosteroids. The very large, progressive induction of TIGR combined with specific structural features of its cDNA suggested that TIGR should be considered a candidate gene for outflow obstruction in glaucoma. Among the properties of TIGR cDNA were a signal sequence for secretion, several structural features for interactions with glycosaminoglycans and other glycoproteins and putative sites for cell surface interactions. In addition, the leucine zippers in the structure were related to TIGR-TIGR oligomerization that was shown to occur with native and recombinant TIGR protein. The verification that TIGR was a major stress response protein in HTM cells following hydrogen peroxide (or phorbol esters) exposure provided a potential link between GC and oxidative mechanisms thought to be involved in glaucoma pathogenesis. Pharmacological evaluation showed that basic fibroblast growth factory and transforming growth factor beta decreased the GC induction of TIGR, and certain nonsteroidal anti-inflammatory drugs protected against both GC- and oxidation-induced stress responses in HTM cells. Our recent studies of TIGR's genomic structure have shown motifs in the promoter region that suggest a basis by which multiple hormonal/environmental stimuli can regulate TIGR production and by which putative genetic alterations could lead to an overexpression of the protein. Further application of cell biology/biochemistry, molecular biology, genetic and histological approaches will be helpful in understanding the role of TIGR in different glaucoma syndromes.

Aged↗
PubMed1990

Trabecular meshwork cellularity. Differences between fellow eyes.

The difference in trabecular meshwork cellularity between fellow eyes was determined in a series of seven pairs of normal human eyes. Variations in cellularity between different quadrants of individual eyes also were determined. Characterization of these differences and development of appropriate sampling techniques to determine trabecular cellularity has become important in light of recent studies that find a decrease in trabecular cell numbers with age and with primary open-angle glaucoma, and the apparent stimulation of trabecular cell division by laser trabeculoplasty. The difference in absolute cell numbers (nuclei per section) between fellow eyes was 12.8% +/- 4.3% (standard error of the mean, SEM). The difference in cellularity (nuclei per solid tissue area) was 9.4% +/- 4.5% (SEM) in a subgroup of five pairs of these eyes. The coefficient of variation between different quadrants of an eye was 18.4% for absolute cell numbers and 17.3% for cellularity for the entire group of eyes. Sample size calculations indicate that for future studies, four pairs of eyes would be needed to detect a 20% difference in absolute cell numbers between fellow eyes and three pairs needed for detecting a similar difference in cellularity (alpha = 0.05, beta = 0.1). At least two quadrants per eye should be examined.

Aged↗
PubMed1999

Human trabecular meshwork cells as a thyroid hormone target tissue: presence of functional thyroid hormone receptors.

PURPOSE: To determine whether human trabecular meshwork cells (HTM) are a potential target tissue for thyroid hormone (3,3',5-triiodothyronine, T3). METHODS: Cultured HTM were assayed for the presence of thyroid hormone receptors (TRs) and retinoid X receptors (RXRs) by reverse-transcriptase polymerase chain reaction (RT-PCR) to detected TR and RXR mRNA, and by immunohistochemistry to detect nuclear TR and RXR proteins. Functionality of the TR was determined by analysis of 125I-T3 binding affinity and capacity in HTM nuclear extracts. Effects of T3 on modulation of hyaluronic acid (HA) levels in HTM were measured as a function of dose and duration of T3 administration. RESULTS: Analysis of RT-PCR and immunohistochemistry demonstrated that cultured HTM expressed TRalpha1, TRalpha2, and TRbeta1 but not TRbeta2; and RXRalpha but not RXRbeta and RXRgamma isoforms. Saturation binding and analysis of 125I-T3 to HTM nuclear extracts revealed Kd of 57 pM. The number of T3 binding sites extrapolated from a Scatchard plot was 7.3 x 10(10)/microg of HTM nuclear protein extract. T3 supplementation reduced the concentration of HA in the cell medium by 32-43% compared to cells grown in the absence of T3. CONCLUSIONS: Cultured HTM express three TR isoforms and one RXR isoform, bind T3 with an affinity similar to that of TR in responsive cells, and modulate their HA production in response to T3. These findings indicate that the human trabecular meshwork tissue has the capacity to respond to thyroid hormones.

Adult↗
PubMed1994

Effects of endothelin-1 on [Ca2+]i and pHi in trabecular meshwork cells.

We examined the effects of endothelin-1 (ET-1) on [Ca2+]i and intracellular pH in cultured bovine trabecular meshwork cells and compared the effects of ET-1 with those of angiotensin II (another phospholipase C activating peptide). [Ca2+]i was measured with the Ca2+ fluorescent dye indo-1. Intracellular pH was measured using the pH sensitive fluorescent dye BCECF. Exposure to ET-1 (10 nM) produced a transient increase in [Ca2+]i (from 77.3 +/- 17.3 nM to 503.0 +/- 64.8 nM, p < 0.05, n = 12). Intracellular pH was also increased during exposure to 10 nM ET-1 (+0.081 unit, p < 0.05, n = 6). In the presence of 10 microM EIPA, ET-1 (10 nM) did not change intracellular pH. Angiotensin II did not significantly change [Ca2+]i or intracellular pH. These results suggest that ET-1 may be involved in the regulation of aqueous humor dynamics by changing [Ca2+]i and intracellular pH in trabecular meshwork cells.

Angiotensin II↗
PubMed1998

[Culture of human trabecular meshwork cells and the cell characteristics of immunohistochemical studies].

OBJECTIVE: To look for better cultural methods in order to obtain numerous human trabecular cells in vitro for glaucoma experimental studies, and describe the immunohistochemical characteristics of the cells. METHOD: Human trabecular meshwork cells were cultured, then 4 monoclonal antibodies were used for immunohistochemical stains of the cultured cells. RESULTS: At the primary period, the growth of human trabecular cells was obviously slower than that of cows and pigs. The immunohistochemical stains showed that the cells presented positive reactions to neuronal specific enolase (NSE) and vimentin and negative reactions to factor VIII related antigen (VIIIR:Ag) and desmin. CONCLUSIONS: The culture of human trabecular meshwork cells in vitro needs more careful and better cultural conditions. The cells originally are derived from embryonic neural crest, not from mesodermal endothelium of blood vessels. There is middle filament vimentin and no desmin in the cells.

Cell Division↗
PubMed1989

The pressures in the episcleral veins, Schlemm's canal and the trabecular meshwork in monkeys: effects of changes in intraocular pressure.

The pressures in the episcleral veins, Schlemm's canal and the trabecular meshwork were studied with a micropuncture technique using cannulas with tip diameters of less than 5 microns. The pressure in Schlemm's canal, Psc, was 14.3 +/- 1.0 cmH2O at spontaneous intraocular pressure, IOP, 19.2 +/- 0.9 cmH2O. The outflow pressure from the anterior chamber to Schlemm's canal was 4.9 +/- 0.7 cmH2O. The relationship between pressures was IOP = 0.73 Psc + 8.7. When the intraocular pressure was increased stepwise from the spontaneous level to 30 cmH2O there was an increase in pressure in Schlemm's canal of 1.7 +/- 0.6 cmH2O, (P less than 0.05). The total outflow resistance and the resistance between the anterior chamber and Schlemm's canal were 3.27 +/- 0.43 and 2.92 +/- 0.50 cmH2O min microliter-1 respectively for the intraocular pressure interval between the spontaneous pressure and a level 4-11 cmH2O higher. In the intraocular pressure range from 20 to 30 cmH2O the corresponding figures were 2.89 +/- 0.45 and 2.69 +/- 0.42 cmH2O min microliter-1 and for the pressure range 25-35 cmH2O, 2.48 +/- 0.58 and 2.31 +/- 0.59 cmH2O min microliter-1. The difference between the total outflow resistance and that between the anterior chamber and Schlemm's canal was about 10% of the total at intraocular pressures below 35 cmH2O. Stepwise increments in IOP increased the trabecular meshwork pressure by 0.88 cmH2O for each cmH2O increase in IOP in the interval of 30-50 cmH2O. The total outflow resistance and the resistance between the anterior chamber and the tip of the microcannula was 3.91 +/- 1.53 and 1.94 +/- 0.99 cmH2O min microliter-1 respectively for the intraocular pressure interval between the spontaneous pressure and 30 cmH2O. In the interval between 30 and 45 cmH2O the corresponding figures were 2.16 +/- 0.66 and 0.20 +/- 0.13 cmH2O min microliter-1. The episcleral venous pressure at the spontaneous intraocular pressure was 14.1 +/- 1.0 cmH2O in seven animals with minimal trauma, and 12.3 +/- 0.8 cmH2O in animals after cannulation of Schlemm's canal. The outflow pressure from the anterior chamber to the episcleral veins was 4.4 +/- 1.2 cmH2O in animals with minimal trauma and 7.1 +/- 0.8 cmH2O after cannulation of Schlemm's canal. The relationship between pressures was IOP = 0.68EVP + 11.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1993

Dexamethasone induced ultrastructural changes in cultured human trabecular meshwork cells.

Glucocorticoid-induced ocular hypertension has been demonstrated in both animals and humans. It is possible that glucocorticoid-induced changes in trabecular meshwork (TM) cells are responsible for this hypertension. In order to elaborate further the effect of glucocorticoids on the trabecular meshwork, the ultrastructural consequences of dexamethasone (DEX) treatment were examined in three different human TM cell lines. Confluent TM cells were treated with 0.1 microM of DEX for 14 days, and then processed for light, epifluorescent microscopy or transmission electron microscopy (TEM). The effect of DEX treatment on TM cell and nuclear size was quantified using computer assisted morphometrics. Morphometric analysis showed a significant increase in both TM cell and nuclear size after 14 days of DEX treatment. Epifluorescent microscopy of rhodamine-phalloidin stained, control TM cells showed the normal arrangement of stress fibers. In contrast, DEX-treated TM cells showed unusual geodesic dome-like cross-linked actin networks. Control TM cells had the normal complement and arrangement of organelles as well as electron dense inclusions and large vacuoles. DEX-treated TM cells showed stacked arrangements of smooth and rough endoplasmic reticulum, proliferation of the Golgi apparatus, pleomorphic nuclei and increased amounts of extracellular matrix material. The DEX-induced alterations observed in the present study may be an indication of the processes that are occurring in the in vivo disease process.

Actins↗
PubMed1990

Fibronectin induces migration of bovine trabecular meshwork cells in vitro.

The migration of cultured bovine trabecular meshwork cells in response to fibronectin was studied using a 48-well migration chamber. Fibronectin was shown to be a potent chemoattractant for these cells, with a dose optimum of 30 micrograms ml-1. At this dose, the number of migrated cells was approximately 12 times that of the control, which was serum-free medium. Analysis of the migratory response revealed it to be mainly a chemokinesis, but chemotaxis was a substantial component. Electron microscopy demonstrated that adhesion and spreading of cells on the surface of the pore-containing membrane are necessary prerequisites to their migration through a pore. Microspikes are abundant during the movement of cellular processes into and through the pores. The migrated cells are extremely thin with a large surface area, but despite this phenotypic alteration the ultrastructure of migrated cells is unchanged.

Animals↗
PubMed1997

Effect of diuretics, channel modulators and signal interceptors on contractility of the trabecular meshwork.

Measurements of isometric tension were performed on isolated trabecular meshwork (TM) and ciliary muscle (CM) strips of the bovine eye. Anterior segments of bovine eyes with well-preserved TM were perfused to measure outflow rate. (1) Bumetanide (10(-4) mol/l) and hydrochlorothiazide (10(-4) mol/l) did not change the contractility of TM and CM strips in the presence or absence of carbachol. Ethacrynic acid dose-dependently relaxed TM and CM strips precontracted either by carbachol or endothelin. (2) Cytochalasin D totally relaxed TM and CM strips precontracted by carbachol. The outflow rate almost doubled after application of cytochalasin D. (3) The effects of various modulators of K+ and Ca2+ channels are summarized. Carbachol and endothelin are postulated to modify nonselective cation channels. An effective blocker of nonselective cation channels (flufenamic acid) relaxed TM and CM precontracted by carbachol or endothelin. These relaxing effects were independent of the relaxing effects of ethacrynic acid and isosorbide dinitrate. (4) Evidence for the presence of various transporters and receptors in TM cells is summarized. (5) The TM per se is a contractile element which is involved in the regulation of aqueous humor outflow. The contractility of TM and CM cells is differently modulated.

Absorption↗
PubMed2003

Expression of matrix metalloproteinases and their inhibitors in human trabecular meshwork cells.

PURPOSE: Matrix metalloproteinases (MMPs) are involved in trabecular meshwork (TM) extracellular matrix metabolism and have been shown to increase aqueous outflow facility. The purpose of this study was to characterize effects of cytokines, a phorbol ester, and prostanoids on the expression of MMP-1, -2, -3, and -9 and tissue inhibitors of metalloproteinases (TIMP)-1 and -2 in cultured human TM cells. METHODS: Five human TM cell strains were treated with selected compounds. Levels of proMMPs and TIMPs in cell media were quantified by ELISA. MMP-3 activity was assayed by casein zymography. RESULTS: All human TM cell strains produced detectable basal amounts of proMMPs and TIMPs. 12-O-tetradecanoyl-phorbol-13-acetate was effective in increasing the levels of proMMP-1, -3, and -9 and TIMP-1. Its effect on proMMP-1 was concentration-dependent with an EC(50) of 2 to 3 nM. Interleukin (IL)-1alpha did not affect levels of proMMP-1 and -2 or the TIMPs, but was most efficacious in increasing proMMP-3 production with an EC(50) of 0.5 ng/mL. The IL-1alpha-induced upregulation of proMMP-3 correlated with an increase in MMP-3 activity. Tumor necrosis factor-alpha activated proMMP-3 production in some but not all cell strains. Platelet-derived growth factor-BB was generally ineffective in modulating MMP and TIMP levels. Prostaglandins E(2) and F(2alpha) at 10 micro M did not affect levels of proMMP-1 or -3. CONCLUSIONS: The expression of the different MMPs and TIMPs in human TM cells was independently regulated. Production of MMP-3 was maximally activated by IL-1alpha. The IL-1alpha-stimulated expression of MMP-3 provides a probable mechanism for IL-1alpha-enhanced aqueous outflow.

Adolescent↗