transforming-growth-factor-beta and Exfoliation-Syndrome

Optic nerve degeneration caused by glaucoma is a leading cause of blindness worldwide. Patients affected by the normal-pressure form of glaucoma are more likely to harbor risk alleles for glaucoma-related optic nerve disease. We have performed a meta-analysis of two independent genome-wide association studies for primary open angle glaucoma (POAG) followed by a normal-pressure glaucoma (NPG, defined by intraocular pressure (IOP) less than 22 mmHg) subgroup analysis. The single-nucleotide polymorphisms that showed the most significant associations were tested for association with a second form of glaucoma, exfoliation-syndrome glaucoma. The overall meta-analysis of the GLAUGEN and NEIGHBOR dataset results (3,146 cases and 3,487 controls) identified significant associations between two loci and POAG: the CDKN2BAS region on 9p21 (rs2157719 [G], OR = 0.69 [95%CI 0.63-0.75], p = 1.86×10⁻¹⁸), and the SIX1/SIX6 region on chromosome 14q23 (rs10483727 [A], OR = 1.32 [95%CI 1.21-1.43], p = 3.87×10⁻¹¹). In sub-group analysis two loci were significantly associated with NPG: 9p21 containing the CDKN2BAS gene (rs2157719 [G], OR = 0.58 [95% CI 0.50-0.67], p = 1.17×10⁻¹²) and a probable regulatory region on 8q22 (rs284489 [G], OR = 0.62 [95% CI 0.53-0.72], p = 8.88×10⁻¹⁰). Both NPG loci were also nominally associated with a second type of glaucoma, exfoliation syndrome glaucoma (rs2157719 [G], OR = 0.59 [95% CI 0.41-0.87], p = 0.004 and rs284489 [G], OR = 0.76 [95% CI 0.54-1.06], p = 0.021), suggesting that these loci might contribute more generally to optic nerve degeneration in glaucoma. Because both loci influence transforming growth factor beta (TGF-beta) signaling, we performed a genomic pathway analysis that showed an association between the TGF-beta pathway and NPG (permuted p = 0.009). These results suggest that neuro-protective therapies targeting TGF-beta signaling could be effective for multiple forms of glaucoma.

Topics: Alleles; Chromosomes, Human, Pair 8; Chromosomes, Human, Pair 9; Exfoliation Syndrome; Genome-Wide Association Study; Glaucoma, Open-Angle; Homeodomain Proteins; Humans; Nerve Degeneration; Optic Nerve; Polymorphism, Single Nucleotide; RNA, Long Noncoding; RNA, Untranslated; Transforming Growth Factor beta

Secondary chronic open-angle glaucoma associated with pseudoexfoliation (PEX) syndrome accounts for approximately 25% of all glaucomas and represents the most common identifiable cause of glaucoma overall. The underlying disorder, PEX syndrome, is a generalized process of the extracellular matrix characterized by production and progressive accumulation of an abnormal extracellular material in many intra- and extraocular tissues. Recent data support the pathogenetic concept of PEX syndrome as a type of elastosis affecting particularly elastic microfibrils. Active involvement of the trabecular meshwork in this characteristic matrix process may lead to glaucoma development in 40-60% of the patients. In addition, PEX syndrome also represents an important risk factor for a broad spectrum of spontaneous or intra- and postoperative ocular complications as well as for systemic cardiovascular diseases. PEX-associated open-angle glaucoma represents a relatively severe and progressive type of glaucoma with a generally poor prognosis due to high intraocular pressure levels and fluctuations in the diurnal pressure curve. The primary cause of chronic pressure elevation appears to be local production of PEX material by trabecular meshwork cells and Schlemm's canal cells with subsequent degenerative changes of Schlemm's canal and juxtacanalicular tissues. Additional pathogenetic factors contributing to pressure increase include pronounced melanin dispersion, increased protein concentrations of the aqueous humor, vascular factors, and connective tissue alterations of the lamina cribrosa. Other types of glaucoma, such as acute open-angle glaucoma, provoked by melanin showers during diagnostic mydriasis, or secondary angle closure glaucoma due to pupillary or ciliary block, are also common in PEX patients. The pathogenetic factors TGF-beta1 and TIMP-1/2 appear to be causally involved in this fibrotic process and thus may represent potential targets for specific, rational therapeutic approaches.

Topics: Exfoliation Syndrome; Extracellular Matrix; Glaucoma, Open-Angle; Humans; Microscopy, Electron; Tissue Inhibitor of Metalloproteinase-1; Tissue Inhibitor of Metalloproteinase-2; Trabecular Meshwork; Transforming Growth Factor beta

Pseudoexfoliation syndrome (PEX) is a critical clinical and biological extracellular matrix systemic disorder. Despite the unknown nature of PEX etiopathogenesis, it is proven to be associated with various genes and factors. The present research focused on analyzing the expression of miR and inflammatory cytokines in PEX. Serum and aqueous humor (AH) were collected prior to cataract surgery or trabeculectomy from 99 participants (64 with PEX glaucoma, and 35 controls). Real-time PCR was used for assessing the expression pattern of some miRNAs namely let-7b, miR-29a, miR-126, miR-34a, and miR-181a-5p. ELISA was carried out to explore the transcription of some inflammatory cytokines such as TGF-β, TNF-α, and IL-6. The indication of our results was a significant enhancement in the expression of let-7, miR-34a, and miR-181a-5p in PEX in contrast to the control group. Notwithstanding a significant suppression in miR-29a, and miR-126 expression levels in PEX in contrast to the control group. Analysis of ROC curve revealed that miR-29a and miR-34a are able to act as useful markers in order to discriminate the PEX group from the PEX negative subjects which were determined as the control group. According to the results obtained, the mean levels of TGF-β, TNF-α, and IL-6 upregulated among PEX subjects in contrast to control samples. In conclusion, our findings indicated that the selected cytokines alongside the selected miRNAs could be introduced as a biomarker panel in the diagnosis of PEX.

Topics: Cytokines; Exfoliation Syndrome; Humans; Interleukin-6; MicroRNAs; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Pseudoexfoliation syndrome (PEXS) is an age-related condition manifesting mainly in ocular tissues. PEXS is manifested through excess aggregation of fibrillary extracellular material at the anterior part of the eye that consists of a plethora of biomolecules, such as different proteoglycans (PGs) and glycosaminoglycans. PEXS is often linked to increased intraocular pressure, and can also lead to pseudoexfoliation glaucoma with very poor prognosis. Various stimuli are known to affect PEXS, including oxidation stress (OS), UV radiation and osmotic pressure. OS, is prominently involved on the progression of the syndrome as it promotes fibrogenesis, possibly via the induction of transforming growth factor-β (TGF-β) and other biomolecular effectors. In addition, PEXS initiation is tightly connected with the dysregulation of extracellular matrix (ECM) homeostasis since aberrant expression of ECM molecules is linked to both the accumulation and low degradation of pseudoexfoliation material. This article aims at uncovering the crucial role of various ECM effectors such as lysyl oxidase-like proteins, matrix metalloproteinases, and TGF-β1, as well as the biochemical pathways involved in the development and the progression of the PEXS.

Topics: Exfoliation Syndrome; Extracellular Matrix; Glycosaminoglycans; Humans; Matrix Metalloproteinases; Protein-Lysine 6-Oxidase; Proteoglycans; Transforming Growth Factor beta; Transforming Growth Factor beta1; Transforming Growth Factors

The purpose of this study is to reveal the participation of different regulatory cytokines within the process of pseudoexfoliation (PEX).. Our study included 140 patients referred to cataract surgery with early and late stage of pseudoexfoliation syndrome (XFS) or pseudoexfoliation glaucoma (XFG). Humor and serum levels of cytokines: transforming growth factor beta (TGF-β), platelet-derived growth factor (PDGF), epidermal growth factor (EGF), insulin-like growth factor (IGF), IL-8 and interferon-inducible T cell alpha chemoattractant (ITAC) were measured in a sample using high sensitivity enzyme-linked immunoabsorbent assay (ELISA) kit.. Our results indicate that profibrotic action induced by increasing TGF-β and PDGF locally activates fibrous tissue production in the early XFS with a prolonged effect of PDGF (late XFS) and finally (XFG stage) it is dominantly controlled by EGF and IGF. ITAC overrides angiogenetic effects of IL-8 in XFG.. Based on our findings, local chronic inflammation in the eye is accompanied by the secretion of different profibrotic cytokines (TGF-β, PDGF, EGF, IGF, IL-8) without angiogenesis due to effects of ITAC.

Topics: Cytokines; Enzyme-Linked Immunosorbent Assay; Epidermal Growth Factor; Exfoliation Syndrome; Humans; Inflammation; Neovascularization, Physiologic; Platelet-Derived Growth Factor; Transforming Growth Factor beta

Pseudoexfoliation syndrome (PEXS) may go along with capsular bag shrinkage and luxation. In the present study, we focus on an association of isoforms of TGF-β with capsular bag luxation.. Aqueous humor was collected intraoperatively from 20 healthy controls and from 73 otherwise healthy patients with PEXS [PEXS without complications (PEX, n = 33), late PEXS with glaucoma (PEXG, n = 30) and with IOL and capsular bag luxation (PEXL, n = 10)]. The concentrations of TGF-β1, TGF-β2 and TGF-β3 were compared using the Bio-Plex® multiplex beads system based on the non-parametric Kruskal-Wallis H test (p < 0.01).. Concentrations of TGF-β 1, TGF-β 2 and TGF-β 3 were higher in the sub-groups PEX and PEXG than in controls (TGF-β 1; p = 0.009 and 0.0005; TGF-β 2; p = 0.002 and 0.005 and TGF-β 3; 0.0005 and 0.0005; respectively), whereas for TGF β2, no significant difference between controls and PEXL was revealed (p = 1.0). TGF-β2 concentrations were elevated in a similar degree in early PEX and PEXG, but not in PEXL compared to controls (p = 0.002). The concentrations of of TGF-β 1 and TGF-β 3 increased in parallel with the progression of disease. The levels of TGF-β 3, however, did not attain pathophysiological levels (>100 pg/ml) in any group.. A stage-dependent increase in the concentrations of TGF-β1 and TGF-β3, but not of TGF-β2, accords to the shrinkage of the capsular bag. This could increase the tension on the zonular fibers and contribute to luxation of the capsular bag.

Topics: Adult; Aged; Aged, 80 and over; Aqueous Humor; Biomarkers; Cataract; Cataract Extraction; Enzyme-Linked Immunosorbent Assay; Exfoliation Syndrome; Female; Follow-Up Studies; Humans; Lens Capsule, Crystalline; Male; Middle Aged; Postoperative Period; Prospective Studies; Protein Isoforms; Time Factors; Transforming Growth Factor beta

Pseudoexfoliation (PXF) is a microfibrillopathy involving disordered elastogenesis. Abnormal extracellular matrix (ECM) production underlies the pathophysiology of PXF. The enzyme Lysyl oxidase (LOX) and its isoforms are known to cross-link the elastin and collagen. Though the etiopathogensis of PXF is not well understood, studies report on the genetic risk involving LOXL1 gene. This study aims to screen LOXL1 coding variants rs1048661 and rs3825942 in the South Indian population and the implication of the single nucleotide polymorphism (SNP) with LOX activity. The levels of transforming growth factor β (TGF-β) in aqueous humor and its correlation with the LOX activity were also examined.. Blood, plasma, and aqueous aspirates were prospectively collected from PXF cases with and without glaucoma and cataract cases as controls. DNA was extracted from 48 PXF cases without glaucoma, 12 PXF cases with glaucoma, and 40 age-matched cataract-alone controls without PXF/glaucoma for analyzing LOX SNPs. LOX activity was measured in aqueous humor and plasma of 30 PXF cases without glaucoma, 24 age-matched cataract-alone controls without PXF/glaucoma, and 14 PXF cases with glaucoma. Protein levels of LOX, LOXL1, LOXL2, and total TGF-β were estimated in plasma and aqueous humor by ELISA.. The specific activity of LOX in aqueous humor was found to be significantly lowered in PXF cases compared with cataract-alone controls (p = 0.014). This decrease in LOX activity in PXF cases was associated with high-risk GG haplotype. However, this was not statistically significant and a larger sample size is warranted. TGF-β1 and TGF-β2 negatively correlated with LOX activity in aqueous humor (p = 0.028; p = 0.046, respectively).. The LOXL1 SNPs, rs1048661 and rs3825942, are associated with PXF in the South Indian population correlating with lowered LOX activity in the aqueous humor. The increased level of total TGF-β in the aqueous humor of PXF cases is possibly associated with LOX regulation which needs further investigation.

Topics: Aged; Amino Acid Oxidoreductases; Aqueous Humor; Case-Control Studies; DNA; Enzyme-Linked Immunosorbent Assay; Exfoliation Syndrome; Female; Genotype; Haplotypes; Humans; Male; Middle Aged; Polymorphism, Genetic; Prospective Studies; Protein-Lysine 6-Oxidase; Transforming Growth Factor beta

To determine the role of the extracellular chaperone clusterin in the pathophysiology of pseudoexfoliation (PEX) syndrome/glaucoma, which is characterized by the stable deposition of abnormal extracellular fibrillar material in anterior segment tissues.. Real-time PCR, in situ hybridization, and immunohistochemistry were applied to analyze the mRNA and protein expression of clusterin in PEX eyes of patients without and with glaucoma and to compare them with eyes of patients with primary open-angle glaucoma and angle-closure glaucoma and with normal control eyes. Aqueous levels of clusterin were determined by Western blot analysis. Real-time PCR and Western blot analysis were used to study the effect of TGF-beta1, which is significantly increased in the aqueous humor of PEX eyes, on clusterin expression by nonpigmented ciliary epithelial cells in vitro.. Clusterin mRNA was ubiquitously expressed in most ocular cells and tissues, particularly in the epithelium of ciliary processes, whereas the protein was mostly located to extracellular structures, such as ocular basement membranes and stromal fibers. Real-time PCR and in situ hybridization displayed significant downregulation of clusterin mRNA in all anterior segment tissues of PEX eyes, irrespective of the presence or type of glaucoma, compared with normal and glaucomatous control eyes, whereas posterior segment tissues did not show any differential expression. A generally decreased immunoreactivity, but a prominent binding of clusterin to all PEX deposits, could be observed in ocular tissues of PEX eyes. Clusterin levels in aqueous humor were significantly reduced in eyes of patients with PEX syndrome compared with normal and glaucomatous control eyes. The expression of clusterin mRNA and protein in nonpigmented ciliary epithelial cells was significantly downregulated by TGF-beta1 in vitro.. Considering the known role of clusterin as a highly efficient extracellular chaperone, its deficiency in the anterior segment of PEX eyes may promote the stress-induced aggregation and stable deposition of the pathologic extracellular matrix product characteristic of PEX syndrome.

Topics: Aged; Aged, 80 and over; Anterior Eye Segment; Blotting, Western; Cell Culture Techniques; Ciliary Body; Clusterin; Down-Regulation; Epithelium; Exfoliation Syndrome; Extracellular Matrix; Female; Fluorescent Antibody Technique, Indirect; Glaucoma, Angle-Closure; Glaucoma, Open-Angle; Humans; In Situ Hybridization; Male; Pigment Epithelium of Eye; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Transforming Growth Factor beta; Transforming Growth Factor beta1

To comparatively investigate the effects of TGF-beta(1) and TGF-beta(2) on extracellular matrix production, proliferation, migration, and collagen contraction of cultured human Tenon's capsule fibroblasts derived from patients with pseudoexfoliation (PEX) syndrome, PEX glaucoma, primary open-angle glaucoma (POAG), and cataract.. Tenon's capsule fibroblasts obtained from four groups of patients were cultured and stimulated with different concentrations (0.1-10 ng ml(-1)) of TGF-beta(1) or TGF-beta(2) for up to 14 days. Cell proliferation was determined with the WST-1 colorimetric assay, cell migration by using the Transwell assay system, and collagen contraction by computerised analysis of three-dimensional collagen lattices and immunohistochemistry for alpha-smooth muscle actin expression. Expression and synthesis of extracellular matrix components (fibronectin, collagen types I and III) was assessed by enzyme-linked immunosorbent assays, by real-time RT-PCR, and by transmission electron microscopy.. Both TGF-beta(1) and TGF-beta(2) in pathophysiological concentrations of 0.1-5 ng ml(-1) stimulated cell proliferation, migration, collagen contraction, alpha-smooth muscle actin expression as well as mRNA expression and secretion of fibronectin, collagen type I, and collagen type III by Tenon's fibroblasts derived from all groups of patients. TGF-beta stimulation occurred in a concentration-dependent manner with different peak activities associated with different fibroblast functions. There was some variability among the different groups of patients with an increased response of cells derived from PEX and POAG patients as compared to cataract patients. Although no statistically significant differences were found between both TGF-beta isoforms, TGF-beta(1) had a more pronounced stimulatory effect on expression and synthesis of extracellular matrix components including the production of elastic microfibrils, particularly in cells derived from patients with PEX syndrome/glaucoma.. These findings suggest a significant contribution of TGF-beta(1) in addition to TGF-beta(2) to the conjunctival scarring process following glaucoma filtration surgery. Due to its pronounced fibrogenic potential, TGF-beta(1) may become another focus for targeting drug therapy, particularly in patients with PEX glaucoma.

Topics: Aged; Cataract; Cell Division; Cell Movement; Cells, Cultured; Collagen; Connective Tissue; Exfoliation Syndrome; Extracellular Matrix; Eye; Female; Fibroblasts; Glaucoma, Open-Angle; Humans; Immunosuppressive Agents; Male; Microscopy, Electron; Reverse Transcriptase Polymerase Chain Reaction; Transforming Growth Factor beta; Transforming Growth Factor beta1; Transforming Growth Factor beta2

The purpose of this study was to evaluate the influence of previous argon laser trabeculoplasty (ALT) on transforming growth factor-beta 2 (TGF-beta 2) concentration of the aqueous humor and its influence on bleb scarring after trabeculectomy.. Fifty-one patients with primary open-angle glaucoma (POAG) and 29 patients with exfoliation (XFS) glaucoma were recruited for this prospective study before undergoing trabeculectomy. Sixty to 200 micro l of aqueous humor were analyzed for total and biologically active TGF-beta 2 concentrations (R and D Systems). TGF-beta 2 levels and a standardized bleb assessment were compared between the ALT- and non-ALT-treated groups.. POAG eyes without ALT showed significantly higher total TGF-beta 2 levels (2,317.7+/-1,041.1 pg/ml) than eyes with previous ALT (1,621.6+/-899.6 pg/ml; P=0.026). No significant difference was found for active TGF-beta 2 levels (ALT: 238.1+/-119.0 pg/ml; no ALT: 220.1+/-96.9 pg/ml; P=0.585). In XFS patients ALT did not alter total TGF-beta 2 levels (ALT: 1,524.9+/-624.9 pg/ml, no ALT: 1,220+/-499.1 pg/ml; P=0.20), but active TGF-beta 2 was significantly higher in the ALT-treated (237.0+/-99.7 pg/ml) than in the non-ALT-treated (140.0+/-95.3 pg/ml, P=0.028) group. Bleb grading revealed no statistical difference between the ALT- and non-ALT-treated groups in POAG (P=0.545, Fisher's exact test), whereas XFS patients with ALT were at increased risk for scarring compared to non-ALT-treated patients (P=0.053).. ALT appears to increase the risk of scarring in XFS patients because of increased levels of activated TGF-beta 2.

Topics: Aqueous Humor; Argon; Blister; Cicatrix; Exfoliation Syndrome; Glaucoma, Open-Angle; Humans; Laser Therapy; Osmolar Concentration; Prospective Studies; Risk Factors; Trabeculectomy; Transforming Growth Factor beta; Transforming Growth Factor beta2

To determine whether clinical characteristics are correlated with increased levels of transforming growth factor-beta 2 (TGF-beta 2) in aqueous humor in glaucomatous eyes.. Aqueous humor samples were collected from 91 glaucomatous eyes. Included were samples from primary open-angle glaucoma (POAG) in 40 eyes, (pseudo)exfoliation syndrome (EXS) in 18 eyes, primary angle-closure glaucoma (PACG) in 26 eyes and uveitis-related secondary glaucoma (SG) in 7 eyes. TGF-beta 2 in aqueous humor was assessed with a specific-capture ELISA.. The mean concentration (+/- standard error) of mature (biologically active) TGF-beta 2 in the aqueous humor of eyes with POAG was 293.6 +/- 33.6 pg/ml, significantly higher than that in eyes with PACG, EXS and SG: 147.5 +/- 28.1, 135.8 +/- 30.2 and 41.0 +/- 10.7 pg/ml, respectively (P = 0.0006, P = 0.0010 and P = 0.0003; analysis of variance). The mean concentration (+/- standard error) of total TGF-beta 2 in the aqueous humor of eyes with POAG was 1647.6 +/- 124.5 pg/ml, not significantly different from that in eyes with PACG, EXS and SG: 1482.9 +/- 148.2, 1442.7 +/- 187.8 and 1929.0 +/- 367.6 pg/ml, respectively. A multivariate analysis using logistic regression showed significant correlations between mature TGF-beta 2 concentration and history of cataract surgery (P = 0.0225) and the use of carbonic anhydrase inhibitors (P = 0.0143).. Our results indicate that increased levels of TGF-beta 2 may play an important role in the pathogenesis of POAG.

Topics: Aged; Aqueous Humor; Enzyme-Linked Immunosorbent Assay; Exfoliation Syndrome; Glaucoma, Angle-Closure; Glaucoma, Open-Angle; Humans; Intraocular Pressure; Middle Aged; Transforming Growth Factor beta; Transforming Growth Factor beta2; Uveitis

To investigate the transforming growth factor beta 2 (TGF-beta 2) levels and total protein levels in the aqueous humor of eyes with different types of glaucoma [primary open-angle glaucoma (POAG), pseudoexfoliation glaucoma (PSX), juvenile glaucoma (JG)], and the relation to filtering bleb development after trabeculectomy.. Aqueous humor was collected at the beginning of surgery from 52 eyes with glaucoma (29 POAG eyes, 17 PSX eyes, 6 JG eyes) and from 29 control eyes that underwent cataract operation. TGF-beta 2 levels (intrinsically activated and total TGF-beta 2) using ELISA methods as well as total protein concentrations of the aqueous humor were determined. All preoperative clinical data of the glaucoma eyes (age, gender, IOP, previous treatment, type of surgery) were compared with the TGF-beta 2 levels. In 40 of these eyes, the postoperative follow-up (filtering bleb development, need for intervention, IOP) was correlated to the preoperatively determined TGF-beta 2 levels.. TGF-beta 2 levels were increased in nearly half of the eyes with POAG and in most of the eyes with JG, but in eyes with PSX, TGF-beta 2 levels were within the normal range. No correlation between TGF-beta 2 levels and age, gender, IOP, previous treatment, or type of surgery, or between TGF-beta 2 levels and protein levels in aqueous humor, was found. Correlation between bleb formation and TGF-beta 2 levels revealed that all but two of the POAG eyes with good clinical outcome (type 1 bleb) had normal levels of activated TGF-beta 2. Of the 13 eyes that needed postoperative intervention (type 2 and type 3 bleb), 8 had high and 5 had normal TGF-beta 2 levels.. PSX eyes differ from POAG and JG eyes not only by their clinical or biomicroscopic appearance, but also by their normal TGF-beta 2 levels in aqueous humor. The fact that most of the POAG eyes with favorable bleb development had normal TGF-beta 2 levels indicated that there might be some relationship between bleb formation and TGF-beta 2 levels. On the other hand, the fact that eyes with less favorable bleb development had both low and high TGF-beta 2 levels indicated that other factors are also involved in the scarring of the filtration bleb.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Aqueous Humor; Child, Preschool; Enzyme-Linked Immunosorbent Assay; Exfoliation Syndrome; Eye Proteins; Female; Glaucoma, Open-Angle; Humans; Male; Middle Aged; Surgical Flaps; Trabeculectomy; Transforming Growth Factor beta; Transforming Growth Factor beta2

Growth factors circulating with the aqueous may play an important role in the pathogenesis of exfoliation syndrome (XFS), which is characterized by excessive synthesis and accumulation of abnormal extracellular material.. We investigated the concentration of three ubiquitous growth factors (TGF-beta1, TGF-beta2 and IGF-1) in the aqueous humour of 50 patients with XFS (27 from Erlangen, 23 from Thessaloniki) and 54 age-matched controls (27 from Erlangen, 27 from Thessaloniki). This study was performed in two centres, independently of each other, using different assay systems.. In the aqueous humour samples collected in Erlangen, both the levels of total TGF-beta1 (P<0.001) and mature TGF-beta1 (P<0.05) were significantly increased in XFS patients compared with controls. Specifically, for total TGF-beta1 patients with XFS exhibited higher a mean value (90.5 +/- 37.4 pg/ml) than controls (30.2 +/- 8.3 pg/ml). The mean level of mature TGF-beta1 was also higher in XFS (14.2 +/- 2.8 pg/ml) than in controls (4.9 +/- 5.5 pg/ml). No difference was found between XFS and controls in the levels of total or mature TGF beta2 in the aqueous or in the level of these two growth factors in the serum. In aqueous humour samples collected in Thessaloniki a significant difference between XFS and controls was also observed for mature TGF-beta1 (XFS 17.06 +/- 11.02 pg/ml vs controls 9.01 +/- 5.69 pg/ml; P=0.006). No difference was observed in TGF-beta2 concentration or IGF-1 concentration in the aqueous. No correlation could be established between protein concentration and the levels of the three growth factors measured. A significant correlation was found between age and protein concentration in XFS, but not in the controls.. Since TGF-beta1 induces the synthesis and accumulation of extracellular matrix, it is hypothesized that TGF-beta1 plays an important role in the pathogenesis of XFS. Our data suggest that the increased levels of TGF-beta1 are most likely due to enhanced local synthesis.

Topics: Aged; Aqueous Humor; Cataract; Exfoliation Syndrome; Eye Proteins; Humans; Immunoenzyme Techniques; Insulin-Like Growth Factor I; Prospective Studies; Transforming Growth Factor beta; Transforming Growth Factor beta1; Transforming Growth Factor beta2

Pseudoexfoliation (PEX) syndrome is a common and clinically important systemic condition characterized by the pathologic production and accumulation of an abnormal fibrillar extracellular material in many intra- and extraocular tissues. Recent evidence suggests that it is a type of elastosis associated with the excess synthesis of elastic microfibrillar components such as fibrillin-1. Since transforming growth factor (TGF)-beta is a major modulator of extracellular matrix formation, the potential involvement of TGF-beta and its latent form binding protein (LTBP) in this aberrant matrix process was investigated. The expression of various isoforms of TGF-beta and LTBP was investigated in the anterior segment tissues of PEX and control eyes on the protein and mRNA level by light and electron microscopic immunohistochemistry, in situ hybridization, and semiquantitative RT-PCR. TGF-beta1 and TGF-beta2 levels were measured in aqueous humor and serum of PEX and control patients by ELISA. Cultures of Tenon's capsule fibroblasts were established to study the effect of TGF-beta1 on fibrillin-1 mRNA expression by Northern blot analysis. Significantly increased concentrations of both total and active TGF-beta1 were measured in the aqueous humor of PEX eyes without and with glaucoma as compared to control eyes, whereas levels of TGF-beta2 were not significantly different. The expression of TGF-beta1, LTBP-1, and LTBP-2, but not TGF-beta2, was markedly increased in anterior segment tissues of PEX eyes, particularly in the non-pigmented epithelium of the ciliary body, on both the mRNA and the protein level. Latent TGF-beta1 staining was consistently associated with PEX material deposits and could be released by proteolytic processing. Double immunolabeling revealed clear co-localization of LTBP-1 and -2 with latent TGF-beta1 and with fibrillin-1 on PEX fibrils. The expression of mRNA coding for fibrillin-1 was up-regulated in vitro by TGF-beta1. This study provides evidence for a significant role of TGF-beta1 and the LTBPs 1 and 2 in PEX syndrome. The results suggest that increased levels of latent and active TGF-beta1 in the aqueous humor of PEX patients, derived from enhanced local synthesis and activation, promote the buildup of the abnormal extracellular elastic material characteristic of PEX syndrome. They further support a dual role for LTBPs, both as integral structural components of PEX fibers and as a means of matrix anchorage of latent TGF-beta1, representing

Topics: Aged; Aqueous Humor; Blotting, Northern; Carrier Proteins; Case-Control Studies; Cells, Cultured; Enzyme-Linked Immunosorbent Assay; Exfoliation Syndrome; Fibrillin-1; Fibrillins; Fibroblasts; Humans; In Situ Hybridization; Intracellular Signaling Peptides and Proteins; Latent TGF-beta Binding Proteins; Microfilament Proteins; Microscopy, Electron; Protein Isoforms; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Transforming Growth Factor beta; Up-Regulation

Pseudoexfoliation (PEX) syndrome is a generalized process of the extracellular matrix characterized by the accumulation of an abnormal pathognomonic material in various intraocular and extraocular tissues. Whereas the intraocular manifestations can be directly diagnosed by biomicroscopic observations, the extraocular manifestations can presently only be diagnosed by electron microscopic methodology. In order to better evaluate the distribution and precise localization of PEX deposits in the various organ systems, we searched for a relatively specific immunohistochemical marker for PEX material on the light microscopic level.. Eyes and tissue specimens of various organ systems (skin, heart, lungs, liver, kidney, abdominal aorta, cerebral artery, plexus choroideus, meninges) obtained from 4 organ donors with ocular PEX syndrome and age-matched control tissues were investigated by electron microscopy and immunohistochemistry using antibodies against various elastic microfibrillar components.. Out of a panel of antibodies tested, the immunolabeling of both intra- and extraocular PEX deposits with antibodies against latent TGF-beta 1 binding protein (LTBP-1) was particularly prominent. In addition to the known intraocular sites of PEX material accumulations, focal plaque-like LTBP-1 positive deposits could be observed in the conjunctival stroma, optic nerve meninges, skin, heart muscle, lungs, kidney as well as in the adventitia of the aorta and cerebral artery from donors with PEX syndrome; such plaque-like deposits positive for LTBP-1 were not present in the control tissues. Transmission electron microscopy confirmed the presence of typical fibrillar PEX aggregates in the respective tissues.. Antibodies against LTBP-1 provide a new and relatively specific marker for PEX deposits both in intraocular and extraocular locations. Systematic screening of PEX accumulations in a larger number of extraocular tissue specimens obtained from PEX patients may help to elucidate the functional implications and consequences of the systemic manifestations.

Topics: Aged; Aged, 80 and over; Antibodies; Arteries; Biomarkers; Carrier Proteins; Case-Control Studies; Diagnosis, Differential; Exfoliation Syndrome; Eye; Humans; Immunohistochemistry; Intracellular Signaling Peptides and Proteins; Kidney; Latent TGF-beta Binding Proteins; Liver; Lung; Microscopy, Electron; Myocardium; Skin; Transforming Growth Factor beta

The pseudoexfoliation (PEX) syndrome which is characterized by the accumulation of an abnormal extracellular material in intra- and extraocular tissues, clinically strictly manifests both unilateral and bilateral. However, the generalized nature of this matrix process does not support unilateral ocular manifestation. The aim of this study, therefore, was a detailed histopathological analysis of the apparently not involved fellow eyes in so-called "unilateral" PEX syndrome.. For transmission electron microscopy, 5 pairs of donor eyes with slitlamp-microscopic, macroscopic and light microscopic evidence of unilateral PEX syndrome and 6 normal control eyes were studied. For immunohistochemistry, light and electron microscopic antibodies against LTBP-1 and HNK-1, two well-known markers for PEX deposits, were used.. All apparently not involved contralateral eyes showed ultrastructural changes in the iris, in the ciliary body and in the trabecular meshwork. These changes include deposits of typical PEX fibrils on iris and ciliary epithelia as well as in the iris dilator muscle, microfibrillar precursors in the periphery of iris vessels, degenerative changes of the iris pigment epithelium and of the dilator muscle and an increased accumulation of extracellular matrix components around iris vessels, in the dilator muscle and in the juxta-canalicular connective tissue of the trabecular meshwork. In all contralateral and PEX eyes, but not in the control eyes, LTBP-1 and HNK-1 positive deposits could be identified in the periphery of iris vessels and in the dilator by light- and electron microscopic immunolabeling.. The observed alterations in contralateral eyes in so-called "unilateral" PEX syndrome support the concept that the PEX syndrome is a generalized, basically bilateral disease which may present in a clinically asymmetric manifestation. This should be considered in the clinical management of these patients.

Topics: Aged; Biomarkers; Carrier Proteins; Case-Control Studies; CD57 Antigens; Exfoliation Syndrome; Eye; Functional Laterality; Humans; Immunohistochemistry; In Vitro Techniques; Intracellular Signaling Peptides and Proteins; Iris; Latent TGF-beta Binding Proteins; Microscopy, Electron; Transforming Growth Factor beta