Higher aqueous levels of matrix metalloproteinases indicated visual impairment in patients with retina vein occlusion after anti-VEGF therapy.

PURPOSE: To investigate the levels of matrix metalloproteinases (MMPs) in aqueous humour of patients with retinal vein occlusion (RVO) and the relationship between intraocular MMP levels and retinal lesion and visual prognosis. MATERIALS AND METHODS: 52 RVO patients, including 23 with central retinal vein occlusion (CRVO) and 29 with branch retinal vein occlusion (BRVO) and 20 participants with senile cataract were enrolled in this study. Retinal lesions were examined by fundus colour photography, fluorescein fundus angiography and optical coherence tomographic angiography. Sixty microliters of aqueous humour were collected during intravitreal anti-Vascular Endothelial Growth Factor (VEGF) injection or cataract surgery. The aqueous levels of MMP-1, MMP-2, MMP-7, MMP-9 and MMP-10 were measured using the Luminex xMAP multiplex assay. The relationship between MMP levels and clinical presentations was analysed by Pearson correlation test. RESULTS: The aqueous humour levels of MMP-1, MMP-2, MMP-7 and MMP-9, but not MMP10 in RVO patients were significantly higher than those in people with cataract after adjusting for age. Further analysis of RVO subgroups showed that the aqueous humour level of MMP2 in CRVO was significantly higher than that in BRVO. The aqueous humour levels of MMP-1 and MMP-2 were positively correlated with superficial capillary plexus vessel density (SVD), whereas the aqueous humour levels of MMP-1 and MMP-7 were negatively correlated with visual improvement following treatment. No correlation between aqueous humour levels of MMP and disease duration and central retinal thickness was observed. CONCLUSIONS: RVO eyes had significantly higher intraocular levels of MMP-1, MMP-2, MMP-7 and MMP-9 than cataract eyes and the level of MMP2 appears to be related to the area of occlusion. Intraocular levels of MMP may positively affect SVD and negatively impact visual function in RVO.

The expression of cytokines in aqueous humor of high myopic patients with cataracts.

Purpose: To analyze the expression of 440 human cytokines in aqueous humor of high myopic patients with cataracts. Methods: Eighty-five patients with cataracts were recruited in this study. In the screening stage, the RayBio G-Series Human Cytokine Antibody Array 440 was used to assay the aqueous humor samples collected from nine high myopic patients with cataracts and eight non-myopic patients with cataracts right before the surgery. The array was further used for verification of the screened cytokines, with aqueous humor samples obtained from 34 eyes of high myopic patients with cataracts and 34 eyes of non-myopic patients with cataracts. Results: Compared with the non-myopic patients with cataracts, the expression levels of decorin, receptor activator of NF-kB (RANK), angiopoietin-1 (ANG-1), C-X-C motif ligand 16 (CXCL16), ß-inducible gene-h3 (bIG-H3), insulin-like growth factor-binding protein 2 (IGFBP-2), and interleukin-17B (IL-17B) were statistically significantly higher in high myopic patients with cataracts (all p<0.000114). The matrix metalloproteinase-2 (MMP-2) level also increased in the aqueous humor of high myopic patients with cataracts (p = 0.0034). The concentrations of ANG-1 and MMP-2 were also increased in the aqueous humor of the confirmatory stage (all p<0.05). Conclusions: In this study, numerous cytokines in aqueous humor were detected in high myopic patients with cataracts and non-myopic patients with cataracts, and it was confirmed that the MMP-2 level in the aqueous humor of patients with high myopia was statistically significantly increased. Further verification also revealed the elevation of ANG-1 in the aqueous humor of high myopic patients with cataracts, which suggests that ANG-1 may be related to the pathogenesis of high myopia.

Targeting the vascular-specific phosphatase PTPRB protects against retinal ganglion cell loss in a pre-clinical model of glaucoma.

Elevated intraocular pressure (IOP) due to insufficient aqueous humor outflow through the trabecular meshwork and Schlemm's canal (SC) is the most important risk factor for glaucoma, a leading cause of blindness worldwide. We previously reported loss of function mutations in the receptor tyrosine kinase TEK or its ligand ANGPT1 cause primary congenital glaucoma in humans and mice due to failure of SC development. Here, we describe a novel approach to enhance canal formation in these animals by deleting a single allele of the gene encoding the phosphatase PTPRB during development. Compared to Tek haploinsufficient mice, which exhibit elevated IOP and loss of retinal ganglion cells, Tek+/-;Ptprb+/- mice have elevated TEK phosphorylation, which allows normal SC development and prevents ocular hypertension and RGC loss. These studies provide evidence that PTPRB is an important regulator of TEK signaling in the aqueous humor outflow pathway and identify a new therapeutic target for treatment of glaucoma.

Tissue Transglutaminase Elevates Intraocular Pressure in Mice.

Purpose: Tissue transglutaminase (TGM2) is elevated in glaucomatous trabecular meshwork (TM) tissues. We investigated whether increased expression of TGM2 increases extracellular matrix crosslinking in the TM, thereby increasing aqueous humor outflow resistance and elevating intraocular pressure (IOP) in mouse eyes. Methods: GTM3, primary human GTM 125-05, and cultured mouse TM cells were transduced with adenovirus serotype 5 expressing human transglutaminase 2 (Ad5.TGM2; multiplicity of infection [MOI]-75) and fixed for immunocytochemistry. To test the effect on IOP in living eyes, Ad5.TGM2 was injected intravitreally into one eye of BALB/cJ (n = 18) or C57BL/6J mice (n = 9). The uninjected contralateral eye and Ad5.GFP served as controls. Daytime conscious IOPs were measured twice per week. Aqueous outflow facility (C) was measured by constant flow infusion on completion of IOP measurements. Immunohistochemistry was performed on BALB/cJ mouse eyes to study TGM2 expression and activity. Results: The treatment of cultured TM cells with Ad5.TGM2 increased immunostaining of N-ε(γ-glutamyl) lysine crosslinks. Ad5.TGM2 injection significantly increased IOP in BALB/cJ (15.86 mm Hg [injected] vs. 10.70 mm Hg [control]) and in C57BL/6J mice (17.09 mm Hg [injected] vs. 12.01 mm Hg [control]). Mean aqueous outflow facility in the injected eyes of BALB/cJ (0.013 µL/min/mm Hg) and C57BL/6J mice (0.012 µL/min/mm Hg) was significantly lower than in the uninjected control eyes (BALB/cJ, 0.021 µL/min/mm Hg; C57BL/6J, 0.019 µL/min/mm Hg). The Ad5.TGM2 transduction of mouse eyes increased TGM2 expression in the TM region and increased N-ε(γ-glutamyl) lysine crosslinks. Conclusions: The increased expression of TGM2 in the TM increases N-ε(γ-glutamyl) lysine crosslinking in the TM, increases aqueous outflow resistance, and elevates IOP in mice. TGM2 may be at least partially responsible for ocular hypertension in POAG.

Utility of angiotensin-converting enzyme activity in aqueous humor in the diagnosis of ocular sarcoidosis.

PURPOSE: Many studies include elevated activity of angiotensin-converting enzyme (ACE) in serum in sarcoidosis and in ocular sarcoidosis as well, but there are only a few analyzing ACE activities in aqueous humor. The aim of this study is to illuminate the diagnostic value of ACE in aqueous humor in patients with ocular sarcoidosis. METHODS: We analyzed twenty patients with ocular sarcoidosis and 18 patients with nonocular involvement. All patients have biopsy-positive sarcoidosis of the lungs and/or mediastinal lymph nodes. Blood samples for ACE serum levels were obtained from all patients. Aqueous humor samples were taken by paracentesis with a 25-gauge needle in local anesthesia. With appropriate statistical tests, we compared ACE activity in serum and aqueous humor in patients with and without ocular sarcoidosis. RESULTS: The majority of our patients with ocular sarcoidosis were female (12/20), also in the group with systemic sarcoidosis and without ocular involvement (12/6). Mean age of the whole analyzed group of sarcoidosis patients was 45 ± 6 years. There is no statistically significant difference in ACE activity in serum between two groups of patients (with and without ocular sarcoidosis). There is statistically significant difference in ACE activity in aqueous humor among patients with ocular and nonocular sarcoidosis. ACE activity in aqueous humor is significantly higher in patients with ocular sarcoidosis. CONCLUSION: Increased ACE activity in aqueous humor can point to a diagnosis of ocular sarcoidosis, without the need for ocular biopsy.

Aqueous humor tyrosinase activity is indicative of iris melanocyte toxicity.

Antibiotics such as fluoroquinolones (FQLs) are commonly used to treat ocular infections but are also known to cause dermal melanocyte toxicity. The release of dispersed pigments from the iris into the aqueous humor has been considered a possible ocular side effect of the systemic administration of FQLs such as Moxifloxacin, and this condition is known as bilateral acute iris transillumination (BAIT). Bilateral acute depigmentation of iris (BADI) is a similar condition, with iris pigment released into the aqueous, but it has not been reported as a side effect of FQL. Iris pigments are synthesized by the melanogenic enzyme tyrosinase (TYR) and can be detected but not quantified by using slit-lamp biomicroscopy. The correlation between dispersed pigments in the aqueous and the extent of melanocyte toxicity due to topical antibiotics in vivo is not well studied. Here, we aimed to study the effect of topical FQLs on iris tissue, the pigment release in the aqueous humor and the development of clinically evident iris atrophic changes. We evaluated this process by measuring the activity of TYR in the aqueous humor of 82 healthy eyes undergoing cataract surgery following topical application of FQLs such as Moxifloxacin (27 eyes, preservative-free) or Ciprofloxacin (29 eyes, with preservative) or the application of non-FQL Tobramycin (26 eyes, with preservative) as a control. In addition, the patients were questioned and examined for ocular side effects in pre- and post-operative periods. Our data showed a significantly higher mean TYR activity in the aqueous humor of Ciprofloxacin-treated eyes compared to Moxifloxacin- (preservative free, p < 0.0001) or Tobramycin-treated eyes (p < 0.0001), which indicated that few quinolones under certain conditions are toxic to the iris melanocytes. However, the reduced TYR activity in the aqueous of Moxifloxacin-treated eyes was possibly due to the presence of a higher drug concentration, which inhibits TYR activity. Consistently, immunoblotting analysis of the aqueous humor from both Ciprofloxacin- and Moxifloxacin-treated eyes showed the presence of soluble TYR enzyme, thus reflecting its toxicity to iris melanocytes and corresponding to its activity in the aqueous humor. Intriguingly, none of these patients developed any clinically appreciable ocular side effects characteristic of BAIT or BADI. Overall, our results suggest that topical antibiotics cause different levels of iris melanocyte toxicity, releasing dispersed pigments into the aqueous humor, which can be measured through TYR enzyme activity. Hence, we conclude that topical FQLs may cause subclinical toxicity to the iris melanocytes but may not be the sole cause of the development of BAIT or BADI.

Correlations Between MMPs and TIMPs Levels in Aqueous Humor from High Myopia and Cataract Patients.

PURPOSE: To study the relationships between matrix metalloproteinases (MMP)-2, MMP-3, and tissue inhibitors of matrix metalloproteinases (TIMP)-1, TIMP-2, and TIMP-3 aqueous humor levels in patients with high myopia or cataract. MATERIALS AND METHODS: MMPs and TIMPs protein levels in 65 aqueous humor samples collected from patients with high myopia or cataract during cataract or clear lens extraction surgery were measured with the Luminex xMAP Technology. The relationship between MMPs and TIMPs levels was analyzed with Spearman's correlation test. RESULTS: MMP-2 levels, but not MMP-3 levels, were increased in the aqueous humor from high-myopia patients. Levels of TIMP-1, -2, and -3 were positively and very significantly correlated with the MMP-2 levels (TIMP-1: r=0.626, p < 0.001; TIMP-2: r = 0.545, p < 0.001; TIMP-3: r = 0.439, p < 0.001). TIMP-2 and-3 levels did not significantly correlate with MMP-3 levels (TIMP-2: r = 0.175, p > 0.05; TIMP-3: r = 0.127, p > 0.05) and TIMP-1 levels only marginally correlated with MMP-3 levels (r = 0.278, 0.01< P < 0.05). CONCLUSIONS: Compared to the present findings with the relationship of MMPs and TIMPs in other fields of medicine, our results are consistent with the homeostasis hypothesis that the increase of TIMPs serves as a compensation reaction to inhibit the excessive degradation caused by the increase of MMPs and limits the development of myopia.

Matrix Metalloproteinase-1 and Matrix Metalloproteinase-9 in the Aqueous Humor of Diabetic Macular Edema Patients.

PURPOSE: To assess the concentrations of matrix metalloproteinase (MMP)-1 and MMP-9 in the aqueous humor of diabetic macular edema (DME) patients. METHOD: The concentrations of MMP-1 and MMP-9 in the aqueous humors of 15 cataract patients and 25 DME patients were compared. DME patients were analyzed according to the diabetic retinopathy (DR) stage, diabetes mellitus (DM) duration, pan-retinal photocoagulation (PRP) treatment, recurrence within 3 months, HbA1C (glycated hemoglobin) level, and axial length. RESULTS: The concentrations of MMP-1 and MMP-9 of the DME groups were higher than those of the control group (p = 0.005 and p = 0.002, respectively). There was a significant difference in MMP-1 concentration between the mild non-proliferative diabetic retinopathy (NPDR) group and the proliferative diabetic retinopathy (PDR) group (p = 0.012). MMP-1 concentrations were elevated in PRP-treated patients (p = 0.005). There was a significant difference in MMP-9 concentrations between the mild NPDR group and the PDR group (p < 0.001), and between the moderate and severe NPDR group and the PDR group (p < 0.001). The MMP-9 concentrations in PRP treated patients, DM patients with diabetes ≥ 10 years and recurrent DME within 3months were elevated (p = 0.023, p = 0.011, and p = 0.027, respectively). In correlation analyses, the MMP-1 level showed a significant correlation with age (r = -0.48, p = 0.01,), and the MMP-9 level showed significant correlations with axial length (r = -0.59, p < 0.01) and DM duration (r = 049, p = 0.01). CONCLUSIONS: Concentrations of MMP-1 and MMP-9 were higher in the DME groups than in the control group. MMP-9 concentrations also differed depending on DR staging, DM duration, PRP treatment, and degree of axial myopia. MMP-9 may be more important than MMP-1 in the induction of DM complications in eyes.

Topical trans-resveratrol ameliorates steroid-induced anterior and posterior segment changes in rats.

Steroid-induced hypertension and glaucoma is associated with increased extracellular meshwork (ECM) deposition in trabecular meshwork (TM). Previous studies have shown that single drop application of trans-resveratrol lowers IOP in steroid-induced ocular hypertensive (SIOH) rats. This IOP lowering is attributed to activation of adenosine A1 receptors, which may lead to increased matrix metalloproteinase (MMP)-2 activity. This study evaluated the effect of repeated topical application of trans-resveratrol for 21 days in SIOH animals on IOP, changes in MMP-2 level in aqueous humor, trabecular meshwork and retinal morphology and retinal redox status. We observed that treatment with trans-resveratrol results in significant and sustained IOP reduction in SIOH rats. This IOP reduction is associated with significantly higher aqueous humor total MMP-2 level; significantly reduced TM thickness and increased number of TM cells. Treatment with trans-resveratrol also significantly increased ganglion cell layer (GCL) thickness, the linear cell density in the GCL and inner retina thickness; and significantly reduced retinal oxidative stress compared to the SIOH vehicle-treated group. In conclusion, repeated dose topical application of trans-resveratrol produces sustained IOP lowering effect, which is associated with increased level of aqueous humor MMP-2, normalization of TM and retinal morphology and restoration of retinal redox status.

Antioxidant content and cytological examination of aqueous fluid from patients with age-related cataracts at different stages.

We investigated the antioxidant content and conducted a cytological examination of the aqueous fluid and lenses of patients with age-related cataracts at different stages. The levels of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-PX) in the aqueous fluid and lenses were determined by the xanthine oxidase method, the colorimetric method, and the improved reduced glutathione (GSH) depletion method, respectively. SOD, CAT, and GSH-PX content in the aqueous fluid and lenses decreased significantly with increasing lenticular nucleus hardness grading. However, the number of white blood cells, neutrophils, monocytes, lymphocytes, and eosinophils did not vary significantly with varying lenticular nucleus hardness. Antioxidant content examination is an important quantitative indicator for clinical diagnosis and treatment of age-related cataracts. Antioxidant content in the aqueous fluid and lenses decreased significantly with increasing lenticular nucleus hardness grading. Lenses at hardness level V had the lowest content of antioxidants.

Serum and aqueous xanthine oxidase levels, and mRNA expression in anterior lens epithelial cells in pseudoexfoliation.

PURPOSE: The aim of this study was to determine serum and aqueous xanthine oxidase (XO) levels, and mRNA expression in anterior lens epithelial cells in pseudoexfoliation (PEX). METHODS: In this prospective study, serum, aqueous and anterior lens capsules were taken from 21 patients with PEX and 23 normal subjects who had undergone routine cataract surgery. Serum and aqueous XO levels were analyzed using the colorimetric method. mRNA expression of XO in anterior lens epithelial cells was evaluated using reverse transcription polymerase chain reaction analysis. RESULTS: Serum XO levels (means ± standard deviations) were 207.0 ± 86.1 IU/mL and 240.6 ± 114.1 IU/mL in the normal and PEX groups, respectively (p = 0.310). Aqueous XO levels (means ± standard deviations) were 65.5 ± 54.3 IU/mL in the normal group and 130.5 ± 117.4 IU/mL in the PEX group (p = 0.028). There was a 2.9 fold decrease in mRNA expression in anterior lens epithelial cells of PEX, which is significantly lower than the normal group (p = 0.01). CONCLUSIONS: Higher aqueous XO levels lacking associated different serum XO suggests higher oxidative stress in the aqueous. Higher aqueous XO levels in PEX with decreased mRNA expression in anterior lens epithelial cells indicate possible overexpression of XO in other structures related to the aqueous.

Prostaglandin agonist effect on matrix metalloproteinase aqueous levels in glaucoma patients.

OBJECTIVE: To determine whether the aqueous levels of matrix metalloproteinases (MMPs) differ between patients with glaucoma treated with topical prostaglandin analogues and normal, nonglaucomatous control patients. Also, to note any difference in MMP levels between latanoprost, travoprost, and bimatoprost that might suggest a difference in efficacy or mechanism of action between these drugs. DESIGN: Prospective, observational study. PARTICIPANTS: Patients who were scheduled to undergo routine intraocular surgery (phacoemulsification or combined phacotrabeculectomy) as part of their standard clinical care were included. Eighteen eyes of 18 patients with glaucoma using any 1 prostaglandin analogue (latanoprost, travoprost, or bimatoprost) were compared with 8 normal control patients. METHODS: This was a multicentre study. Aqueous humour (0.2 mL) was aspirated at the beginning of the intraocular surgery through a clear corneal paracentesis. MMP-2 and -9 were quantified in the aqueous of all participants using enzyme-linked immunosorbent assay. RESULTS: There was no significant difference in the levels of either MMP-2 (p = 0.216) or MMP-9 (p = 0.552) between the control patients and the patients with glaucoma on prostaglandins. There was no difference in the levels of MMP-2 or -9 between the latanoprost, travoprost, or bimatoprost groups. CONCLUSIONS: The levels of MMP-2 and -9 in aqueous of glaucomatous eyes on topical prostaglandin analogues were the same as those of normal age-matched control patients. This could reflect either a return to normal levels with efficacious treatment or a lack of difference between disease and nondisease states.

MMP-2, MMP-3, TIMP-1, TIMP-2, and TIMP-3 protein levels in human aqueous humor: relationship with axial length.

PURPOSE: We measured the aqueous humor levels of matrix metalloproteinases (MMP) MMP-1, MMP-2, MMP-3, and tissue inhibitors of matrix metalloproteinases (TIMP) TIMP-1, TIMP-2, and TIMP-3 in patients with myopia or cataract, and investigated the relationship between their levels and axial length (AL). METHODS: We measured MMP/TIMPs levels with the Luminex xMAP Technology by using commercially available Milliplex xMAP Kits. A total of 65 aqueous humor samples was collected from patients with myopia or cataract during cataract or clear lens extraction surgery. According to the AL, the samples were divided into three groups: group A, AL ≤ 24 mm; group B, AL 24 to 26 mm; and group C, AL ≥ 26 mm. RESULTS: Levels of MMP-2, MMP-3, TIMP-1, TIMP-2, and TIMP-3 could be detected in the aqueous humor. The levels of MMP-2, TIMP-1, TIMP-2, and TIMP-3 were positively correlated with AL. The differences of the levels of these MMPs/TIMPs among the three groups were statistically significant. The MMP-3 levels were not correlated with AL and there was no significant difference in MMP-3 levels among these three groups. Levels of MMP-1 could not be detected in the aqueous humor samples. CONCLUSIONS: Elevated levels of aqueous MMP-2, TIMP-1, TIMP-2, and TIMP-3 were found in the eyes with elongated axis.

Lysyl oxidase-like 2 level and glaucoma surgical outcomes.

PURPOSE: To evaluate the levels of TGF-ß and lysyl oxidases in both the aqueous humor and in Tenon's tissue in patients with POAG, and to assess their association with bleb morphological features and outcomes of glaucoma surgery. METHODS: Eighteen POAG patients scheduled to undergo glaucoma surgery and 17 healthy controls were enrolled. At the time of surgery, approximately 0.1 mL aqueous humor through an anterior chamber paracentesis and a 4 × 4-mm sample of Tenon's tissue were obtained. Concentrations of TGF-ß and lysyl oxidases (types 1 and 2) were analyzed by ELISA. The bleb morphologic features based on the Moorfields Bleb Grading System were evaluated by bleb photographs. RESULTS: The TGF-ß in Tenon's tissue and lysyl oxidase-like 2 in aqueous humor and in Tenon's tissue were significantly elevated in POAG patients. When POAG patients were divided by outcome 1 year after surgery, lysyl oxidase-like 2 protein was significantly higher in both aqueous humor and Tenon's tissue of the failure group. The level of lysyl oxidase-like 2 protein was significantly correlated with that of TGF-ß in the Tenon's tissue. Lysyl oxidase-like 2 level in the aqueous humor (r = 0.563, P < 0.001) and Tenon's tissue (r = 0.760, P < 0.001) had significantly negative correlation with bleb area. CONCLUSIONS: The TGF-ß and lysyl oxidase-like 2 levels at the time of surgery were significantly correlated with 1-year outcomes of glaucoma surgery. The level of lysyl oxidase-like 2 was significantly correlated with that of TGF-ß, suggesting induction by TGF-ß. Modulation of lysyl oxidase-like 2 levels may have important applications in glaucoma surgery.

Lipocalin-like prostaglandin D synthase (L-PGDS) concentration in aqueous humour in patients with open-angle glaucoma.

PURPOSE: To report on the concentration of lipocalin-like prostaglandin D synthase (L-PGDS) in the aqueous humour (AH) in patients with open-angle glaucoma (OAG). PATIENTS AND METHODS: Prospective assessment in 20 patients (13 female, 7 male, mean age 74±10.6 y) who underwent surgery for OAG. AH was sampled and analyzed for L-PGDS concentration. AH from 26 patients (11 female, 15 male, 72.4±14.4 y) without glaucoma who underwent cataract surgery, served as control subjects. RESULTS: The L-PGDS concentration in the AH sampled from the anterior chamber in the OAG group (5.9±2.4 mg/L) was significantly (P<0.001) higher than in the control group (3.3±1.3 mg/L). There were no significant differences between the concentrations of L-PGDS between the left and the right eye or between genders. CONCLUSIONS: L-PGDS concentration in the AH of patients with OAG was significantly elevated compared with its concentration in the AH of nonglaucomatous eyes. As L-PGDS is a biologically pluripotent protein, its possible role in glaucoma warrants further examination.

Human aqueous humor phosphatase activity in cataract and glaucoma.

PURPOSE: To investigate the presence and activity of protein phosphatase-2A (PPase2A), protein phosphatase-2C (PPase2C), and protein tyrosine phosphatases (PTPs) in the human aqueous humor (AH) of patients with primary open-angle glaucoma (POAG) and cataract and to study the correlation between these phosphatases and the redox state of the AH. METHODS: Eighty-six cataract patients and 29 POAG patients who were scheduled for cataract surgery with or without glaucoma surgery were enrolled in the study. PPase2A, PPase2C, and PTPs levels in AH were measured by enzyme-linked immunosorbent assays, Western blot analyses, and spectral METHODS: The redox state was measured by spectral and fluorescent methods. RESULTS: Phosphatase activity-positive results were significantly higher in AH samples from the POAG group (PP2A χ(2)(1) = 11.754, P < 0.01; PP2C χ(2)(1) = 8.754, P < 0.01; PTP χ(2)(1) = 11.073, P < 0.01). Western blot analysis revealed higher PP2C levels in the AH of glaucoma patients compared with PP2C levels in the AH of cataract patients (P = 0.012). Both oxidized/reduced glutathione ratios and superoxide dismutase levels in the AH were significantly higher in the glaucoma group than in the cataract group. Finally significant correlations were found between PP2A and PP2C, PP2A and PTP, and total antioxidant activity and PTP levels. CONCLUSIONS: There is a statistically significant difference between phosphatase levels in the AH of POAG patients and cataract patients. The phosphatase content of the AH represents tissue pathology, but their presence in the AH may be attributed to cell debris or to active signaling to other molecular events.

Connective tissue growth factor and tissue inhibitor of matrix metalloproteinase-2 in patients with exfoliative glaucoma.

PURPOSE: To investigate the aqueous humor levels of connective tissue growth factor (CTGF), matrix metalloprotinease-2 (MMP-2), and tissue inhibitor of matrix metalloprotinease-2 (TIMP-2) in human eyes with exfoliative glaucoma, primary open-angle glaucoma, and senile cataract patients. PATIENTS AND METHODS: This was a prospective, comparative study. Sixty patients with glaucomas and 25 patients with senile cataract of matched age and gender were enrolled in this study. Patients were classified into three groups: group I comprised 30 patients with exfoliative glaucoma (XFG), group II comprised 30 patients with primary open-angle glaucoma (POAG), and group III comprised 25 patients with senile cataract (controls). Aqueous humor samples were obtained by paracentesis at the time of elective surgery for glaucomatous and cataractous patients. CTGF, MMP-2, and TIMP-2 were measured in aqueous humor by specific enzyme linked immunosorbent assay (ELISA) kits, and total aqueous humor protein content was assessed by the Lowry method. RESULTS: There were significant increases in aqueous humor levels of CTGF and TIMP-2 in XFG patients compared to the corresponding values of POAG patients or controls. The MMP-2 aqueous humor level was significantly increased in the XFG patients when compared with controls (P < 0.001). Moreover, the total protein level in the aqueous humor of eyes of the XFG patients was significantly higher than in POAG patients or controls (P < 0.001). A positive correlation was found between CTGF and MMP-2 in aqueous humor samples of XFG patients (P < 0.001). CONCLUSION: Increased levels of aqueous humor of CTGF and TIMP-2 may promote the abnormal extracellular matrix accumulation and may be involved in the pathogenesis of XFG.

Plasma and aqueous humor angiotensin-converting enzyme levels in patients with diabetic retinopathy.

PURPOSE: To assess angiotensin-converting enzyme (ACE) levels in aqueous humor and plasma of patients with nonproliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR) as another potent ischemia-induced angiogenic factor. METHODS: The clinical comparative study included 40 patients with diabetic retinopathy and 16 healthy subjects. For all patients, aqueous humors were collected during the cataract surgery or intravitreal injection of triamcinolone acetonide. ACE levels were measured using a solid-phase chemiluminescence immunoassay. RESULTS: We observed significantly elevated ACE level in aqueous humor of patients with PDR compared with the patients with NPDR and normal subjects (P = 0.023), but no significant difference was detected between nonproliferative diabetics and control group (P = 0.239). There was no significant difference in plasma ACE levels among diabetic and control groups (P = 0.816). CONCLUSION: Elevated ACE level may induce retinal angiogenesis and proliferative retinopathy in patients with DM. We consider that high levels of ACE in aqueous humor can reflect the association between retinal angiogenesis and DM serve as predictor in the progression of diabetic retinopathy.

Oxidative stress markers in patients with primary open-angle glaucoma.

PURPOSE: To investigate the levels of antioxidant enzymes catalase (CAT), glutathione peroxidase (GPO), superoxide dismutase (SOD), and malondialdehyde (MDA) in human eyes with primary open-angle glaucoma (POAG) and to correlate their concentrations with severity of glaucoma. DESIGN: A prospective cases control study. PATIENTS AND METHODS: Thirty patients with primary open-angle glaucoma and twenty-five patients with senile cataracts of matched age and gender were included in the study prospectively. Aqueous humor samples were obtained by paracentesis at the time of elective surgery for glaucomatous and cataractous patients. Aqueous humor were analyzed for CAT, GPO, SOD, and MDA status. RESULTS: GPO, SOD, and MDA enzyme levels revealed a high significant increase in aqueous humor of POAG patients with respect to the comparative group of cataract patients (P < 0.001). No significant difference in the activity of CAT enzyme in aqueous humor of POAG and cataract patient (P = 0.201). Significant correlation was found between the MDA enzyme level and severe visual field loss (P < 0.001) in POAG patients. CONCLUSION: Increased levels of aqueous humor GPO, SOD, and MDA may be associated with POAG. In addition, they may be useful antioxidant enzyme levels in aqueous humor of POAG patients as a result of glaucoma disease and not a cause.

Smoking, an additional risk factor in elder women with primary open-angle glaucoma.

PURPOSE: Smoking is a serious public health problem worldwide. Some authors refer to it as the "silent epidemic of the 20th century." It constitutes an important risk factor for ocular pathologies such as age-related macular degeneration (ARMD), diabetic retinopathy, and neuropathy because the toxic effects of tobacco play a key role in the deterioration of eye tissue. Damage to trabecular meshwork cells (TMC) and retinal ganglion cells (RGC), involving inflammation and apoptosis mechanisms, has been proved in glaucoma. The aim of this study was to determine whether smoking influences the progression of primary open angle glaucoma (POAG) in women. METHODS: This experimental study involved a sampling of consecutive cases of smokers, ex-smokers and non-smokers women with POAG. One hundred and twenty women with POAG, aged 40-90 years, were enrolled (40 smokers, 40 ex-smokers and 40 non-smokers). Samples of aqueous humor (AH) and plasma from each subject were obtained at the beginning of the surgical procedures. Both inflammation and apoptosis processes in the subjects were studied by means of enzyme immunoassay and western blot procedures respectively. We analyzed the interleukin-6 (IL-6) levels as an inflammation marker and the expression of caspase-3 and poly (ADP-ribose) polymerase 1 (PARP-1) as apoptosis markers. RESULTS: IL-6, caspase-3, and PARP-1 levels were significantly higher in the smoker women who smoked than in the ex-smoker and non-smoker glaucomatous groups of the same gender (p<0,05). CONCLUSIONS: Inflammation and apoptosis marker levels increase with smoking in the aqueous humor and plasma samples of POAG women. Smoking could be an important additional risk factor for glaucoma progression in elderly women.