Extracts of different pollen species and their effect on human tear fluid and an epithelial cell line.

PURPOSE: Hazelnut and birch pollen are known to destroy tear film components and attack ocular surface cells. We investigated further pollen species from different plant families, whether they show similar effects on human tear fluid and an epithelial cell line in vitro, to provide a broad basis for further research on pollen reactions affecting the tear film and ocular surface. MATERIALS AND METHODS: Regional pollen species from different plant families (Adoxaceae, Betulaceae, Fagaceae, Juglandaceae, Malvaceae, Oleaceae, Pinaceae, Plantaginaceae, Poaceae, Salicaceae, Sapindaceae) were collected. Their proteolytic activity was evaluated by Zymography. Human tear fluid and cells of an epithelial cell line were incubated with pollen extracts. Tear fluid was analyzed by Polyacrylamide gel electrophoresis (PAGE). Cytomorphology was assessed microscopically and cell viability by proliferation (MTS), water-soluble tetrazolium (WST-1) assay and the impedance-based xCELLigence real-time analysis (RTCA). RESULTS: Zymography revealed significant protease activity and PAGE showed the degradation of tear proteins by different pollen species. Cells incubated with pollen extracts presented dose- and time-dependent cytomorphological changes. MTS, WST-1, and RTCA revealed cytostatic as well as cytotoxic effects of pollen extracts. CONCLUSIONS: Pollen species from different plant families exert proteolytic activity and degrade human tear fluid as well as epithelial cells, which may play a crucial role in the pathogenesis of allergic and non-allergic reactions affecting the ocular surface.

Decreased viability and proliferation of CHANG conjunctival epithelial cells after contact with ultraviolet light-irradiated pollen.

CONTEXT: Contact with pollen is the major reason for the development of allergic symptoms on the ocular surface leading to a significant increase of allergic diseases worldwide. Environmental changes such as increased ultraviolet (UV) radiation and air pollution are discussed as contributory causes for this increase. OBJECTIVE: We investigated the effect of UV light on the histamine content of pollen and examined if an irradiation of pollen affects the viability and proliferation of conjunctival cells. MATERIALS AND METHODS: Alder (Alnus glutinosa) and hazel (Corylus avellana) pollen were irradiated for different time periods with sunlight, UV-A or UV-B light and the histamine content was analysed and compared with non-irradiated pollen. Conjunctival epithelial cells (CHANG cells) were exposed to irradiated and non-irradiated pollen followed by an assessment of cell viability with the colorimetric MTS test and the impedance-based measurement of cell proliferation using the xCELLigence real-time analysis system. RESULTS: UV light irradiation increased the histamine level of alder and hazel pollen in a dose-dependent manner. CHANG cells treated with irradiated pollen induced a statistically significant higher decrease of cell viability than treatment with non-irradiated pollen. DISCUSSION AND CONCLUSIONS: Our results indicate that UV light is able to alter pollen thus making them more harmful for conjunctival cells.

Role of cholesterol 24S-hydroxylase gene polymorphism (rs754203) in primary open angle glaucoma.

PURPOSE: The enzyme cholesterol 24S-hydroxylase (Cyp46A1) is responsible for the conversion of cholesterol to its more polar metabolite 24S-hydroxycholesterol, thereby enabling the intracerebral elimination of cholesterol. An intronic single nucleotide polymorphism in the gene CYP46A1 (IVS2 -150 T>C; rs754203) has recently been associated with primary open angle glaucoma (POAG). This association, however, lacks confirmation in other studies. The purpose of the present study was to investigate a hypothesized association between rs754203 and the presence of POAG in a Central European population of Caucasian descent. METHODS: The present institutional study comprised a total of 581 unrelated subjects: 330 patients with POAG, and 251 control subjects. Main outcome measures are genotype distributions and allelic frequencies determined by polymerase chain reaction. RESULTS: No significant differences in either genotype distribution or allelic frequencies were found between patients with POAG and control subjects (p>0.05). The presence of the rs754203 T-allele was associated with a nonsignificant odds ratio of 0.81 (95% CI: 0.63-1.04; p=0.11) for POAG. CONCLUSIONS: Our data suggest that the rs754203 polymorphism itself is unlikely a genetic risk factor for POAG in Caucasian individuals.

Role of inflammation-related gene polymorphisms in patients with central retinal vein occlusion.

OBJECTIVE: Central retinal vein occlusion (CRVO) is a vision-threatening disease, primarily occurring among patients aged more than 60 years. Several risk factors, including arterial hypertension and diabetes mellitus, have been identified. Compression of the central retinal vein by an atherosclerotic retinal artery at the lamina cribrosa also has been implicated in the pathogenesis of the disease. Functional gene polymorphisms of cytokines or chemokines previously shown to affect atherogenesis or hemostasis are potential risk factors for CRVO. The present study investigates a hypothesized association between inflammation-related gene polymorphisms and the presence of CRVO in a relatively large cohort of patients. DESIGN: Case-control study. PARTICIPANTS: The study group consisted of 315 patients with CRVO and 335 control subjects. METHODS: Determination of genotypes was done by 5' exonuclease assay (TaqMan). MAIN OUTCOME MEASURES: Genotypes of interleukin (IL)1ß -511C>T, IL1 receptor antagonist (IL1RN) 1018T>C, IL4 -584C>T, IL6 -174G>C, IL10 -592C>A, IL18 183A>G, tumor necrosis factor (TNF)-α -308G>A, monocyte chemoattractant protein (MCP)-1/CCL2 -2518A>G, IL8 -251A>T, and RANTES (CCL5) -403G>A polymorphisms. RESULTS: Genotype distributions and allele frequencies of the investigated gene polymorphisms did not significantly differ between both groups (P>0.05). Arterial hypertension, diabetes mellitus, and cigarette smoking were significantly more frequent in patients with CRVO than among control subjects (arterial hypertension: 67.0% vs. 52.2%, P<0.001; diabetes mellitus: 16.8% vs. 6.3%, P<0.001, cigarette smoking: 32.1% vs. 23.6%, P = 0.02). In a logistic regression analysis, the presence of arterial hypertension was associated with an odds ratio (OR) of 1.75 (95% confidence interval [CI], 1.26-2.44) in those with CRVO, whereas an OR of 2.52 (95% CI, 1.46-4.35) was found in those with diabetes mellitus. A history of cigarette smoking was associated with an OR of 1.57 (95% CI, 1.09 - 2.25) for CRVO. CONCLUSIONS: Our data suggest that the investigated inflammation-related gene polymorphisms are unlikely major risk factors for CRVO. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

The redox state of human serum albumin in eye diseases with and without complications.

PURPOSE: To investigate the redox state of human serum albumin concerning cysteine-34 as a possible systemic redox marker in patients with different eye diseases with and without complications and with consideration of possible effects of age. METHODS: Cataract (CAT), glaucoma, age-related macular degeneration (AMD), diabetes mellitus (DM), diabetic retinopathy and hypertension were the pathologies investigated. Albumin redox state concerning cysteine-34 was measured by high-performance liquid chromatography with fluorescence detection. The separation gives three fractions: the fully reduced form containing a thiol group, the disulphide form and a higher oxidized form. Statistical analysis was done by Student's t-test, analysis of variance and stepwise regression analysis. RESULTS: Albumin as a systemic marker for oxidative stress was shifted to a more oxidized state by DM. An even stronger shift to the oxidized form was observed in patients with proliferative diabetic retinopathy. Notably, these effects were independent from age. In contrast, CAT and AMD had no influence on serum albumin redox state. CONCLUSION: Serum albumin is not shifted to more oxidized forms by localized oxidative stress, but it is in systemic diseases like DM.

Role of functional single nucleotide polymorphisms of MMP1, MMP2, and MMP9 in open angle glaucomas.

PURPOSE: Matrix metalloproteinases (MMPs) play an essential role in the turnover of the extracellular matrix and cellular behavior. MMP1, MMP2, and MMP9 have previously been implicated in the pathogenesis of primary open angle glaucoma (POAG) and open angle glaucoma secondary to exfoliation syndrome (XFG), respectively. Functional gene polymorphisms of these MMPs such as MMP1 -1607 1G/2G (rs1799750), MMP2 -1306 C/T (rs243865), MMP2 -1575 G/A (rs243866), and MMP9 Q279R (rs17576) are thus plausible candidates as risk factors for open angle glaucomas. The purpose of the present study was to investigate hypothesized associations between these polymorphisms and the presence of POAG and XFG in a Caucasian population. METHODS: The present case-control study included 322 patients with POAG, 202 patients with XFG, and 248 control subjects. Genotyping of polymorphisms was done using polymerase chain reaction. RESULTS: No significant differences in either genotype distributions or allelic frequencies of MMP1 -1607 1G/2G, MMP2 -1306 C/T, MMP2 -1575 G/A, and MMP9 Q279R were found between patients with POAG and control subjects and patients with XFG and control subjects, respectively (p>0.05). The presence of POAG or XFG was not predicted by any of the investigated polymorphisms. CONCLUSIONS: Our data suggest that the MMP1 -1607 1G/2G, MMP2 -1306 C/T, MMP2 -1575 G/A, and MMP9 Q279R polymorphisms themselves are unlikely major risk factors among Caucasian patients with either POAG or XFG.

The effect of iodide iontophoresis on the antioxidative capacity of the tear fluid.

BACKGROUND: Environmental oxidative stress changing the properties of the tear fluid can lead to keratoconjunctivitis sicca (dry eye syndrome). The aim of this study was to determine whether iodide iontophoresis influences the antioxidative capacity (ACW = water soluble antioxidative capacity) of the tear fluid, and to compare iodide iontophoresis with other balneotherapeutic measures. METHODS: This prospective study evaluated 92 patients in four groups. Twenty-four patients were treated with iodide iontophoresis, 24 with other balneotherapeutic methods. Twenty-five patients received iodide iontophoresis combined with other balneotherapeutic methods and 21 persons received no treatment (control). Unstimulated tear fluid, serum and urine were collected. ACW was determined photochemically in tear fluid and serum; iodine was measured in urine photometrically. RESULTS: Iodide iontophoresis increases the ACW of the tear fluid but not the ACW of the serum. Other iodine therapies increase the ACW in serum but not in tear fluid. Iodine excretion in urine was increased in all treated groups compared to the control. CONCLUSION: The increase of ACW in tear fluid after iodide iontophoresis can support the defense mechanism of the eye against oxidative influence effects, which may alleviate the symptoms of keratoconjunctivitis sicca.

Pollen enzymes degrade human tear fluid and conjunctival cells: an approach to understanding seasonal non-allergic conjunctivitis.

BACKGROUND: During pollen seasons, allergy-like symptoms can be observed in proven non-allergy sufferers. Pollen enzymes are thought to be responsible for conjunctival irritation. We investigated the influence of the well-known aggressive pollen species hazelnut (Corylus avellana) and birch pollen (Betula pendula) on both human tear fluid and conjunctival cell cultures. This study is an approach to seasonal non-allergic conjunctivitis (SNAC) syndrome. METHODS: Zymography was carried out in order to investigate the proteolytic activity of the pollen. Thereafter, human tear fluid was incubated with pollen extract, and the results were studied by polyacrylamide gel electrophoresis. In addition, cultivated conjunctival cells (CHANG cells) were incubated with pollen extracts. Cytomorphological changes were analyzed using the CASY1 Cell Counter. Cell viability was quantified via MTS assay. The viability of the cells which were incubated with pollen extract was compared to the viability of control cells. RESULTS: Pollen proteases destroy tear fluid proteins, as observed by polyacrylamide gel electrophoresis. The treatment of CHANG cells with pollen extract induced a statistically significant decrease in cell viability, depending on the pollen extract concentration and the incubation period. CONCLUSION: Evidence of the destruction of tear fluid proteins and damage to human conjunctival cells by pollen proteases explains conjunctival irritation in proven non-allergic people during the pollen season. One reason why not all people are affected by SNAC syndrome to the same extent could be differences in the concentrations of antiproteases present on the ocular surface.

Positive influence of hyaluronate on cell vitality of human conjunctival cells after alkali injuries.

BACKGROUND: To analyse the influence of hyaluronate (HA) on the cell vitality of human conjunctival cells after chemical injuries from NaOH or alkali-containing household cleaners. METHODS: Human conjunctival cells (Chang cells) were incubated either with NaOH solutions or dilutions of household cleaners. HA (0.025%) was added to the cell culture medium of part of the cells subsequent to chemical injuring. After 24 h the cell vitality of the HA-incubated cells, determined by MTS assay (Cell Titer 96(R) Aqueous One Solution Cell Proliferation Assay), was compared to the control cells without HA addition. RESULTS: The addition of HA to the cell culture medium subsequent to chemical injuring resulted in a significantly lower decrease in cell vitality (mean difference: 11.79; p = 0.00; CI = 98%). CONCLUSION: Because HA attenuates the decrease in cell vitality of alkali-damaged human conjunctival cells, formulations containing HA may be recommended for the treatment of chemical injuries to the anterior part of the eye.

Mitochondrial DNA haplogroup T is associated with coronary artery disease and diabetic retinopathy: a case control study.

BACKGROUND: There is strong and consistent evidence that oxidative stress is crucially involved in the development of atherosclerotic vascular disease. Overproduction of reactive oxygen species (ROS) in mitochondria is an unifying mechanism that underlies micro- and macrovascular atherosclerotic disease. Given the central role of mitochondria in energy and ROS production, mitochondrial DNA (mtDNA) is an obvious candidate for genetic susceptibility studies on atherosclerotic processes. We therefore examined the association between mtDNA haplogroups and coronary artery disease (CAD) as well as diabetic retinopathy. METHODS: This study of Middle European Caucasians included patients with angiographically documented CAD (n = 487), subjects with type 2 diabetes mellitus with (n = 149) or without (n = 78) diabetic retinopathy and control subjects without clinical manifestations of atherosclerotic disease (n = 1527). MtDNA haplotyping was performed using multiplex PCR and subsequent multiplex primer extension analysis for determination of the major European haplogroups. Haplogroup frequencies of patients were compared to those of control subjects without clinical manifestations of atherosclerotic disease. RESULTS: Haplogroup T was significantly more prevalent among patients with CAD than among control subjects (14.8% vs 8.3%; p = 0.002). In patients with type 2 diabetes, the presence of diabetic retinopathy was also significantly associated with a higher prevalence of haplogroup T (12.1% vs 5.1%; p = 0.046). CONCLUSION: Our data indicate that the mtDNA haplogroup T is associated with CAD and diabetic retinopathy in Middle European Caucasian populations.

Analysis of inflammation- and atherosclerosis-related gene polymorphisms in branch retinal vein occlusion.

PURPOSE: Branch retinal vein occlusion (BRVO) is a common vision-threatening disease. Compression of the underlying retinal vein due to increased rigidity of the crossing artery has been implicated in the pathogenesis of BRVO. Among others, arterial hypertension and hypercholesterolemia, both of which contribute to atherogenesis, have been identified as risk factors. Atherosclerosis itself is a chronic low-grade inflammatory disease with a distinct pro-inflammatory cytokine pattern. In addition to their role in atherogenesis, some cytokines have been shown to exert procoagulatory effects, and may thus contribute to the development of BRVO by a second mechanism. Gene polymorphisms affecting the expression of inflammation-related cytokines are therefore candidates as potential risk factors for BRVO. The purpose of the present study was to investigate hypothesized associations between cytokine gene polymorphisms and the presence of BRVO. METHODS: The study comprised 398 patients with BRVO and 355 control subjects. Using 5'exonuclease assays (TaqMan), genotypes of the following functional single nucleotide polymorphisms were determined: interleukin 1 beta (IL1B) -511C>T, interleukin 1 receptor antagonist (IL1RN) 1018T>C, interleukin 4 (IL4) -584C>T, interleukin 6 (IL6) -174G>C, interleukin 8 (IL8) -251A>T, interleukin 10 (IL10) -592C>A, interleukin 18 (IL18) 183A>G, tumor necrosis factor (TNF) -308G>A, monocyte chemoattractant protein 1 (CCL2) -2518A>G, and RANTES (CCL5) -403G>A. RESULTS: Neither genotype distributions nor allele frequencies of any of the investigated polymorphisms differed significantly between BRVO patients and controls (p>0.05). Arterial hypertension was found to be significantly more prevalent in BRVO patients than in controls (p<0.001). In a logistic regression analysis presence of arterial hypertension was associated with an odds ratio of 3.33 (95% confidence interval: 2.42-4.57) for BRVO. CONCLUSIONS: As none of the investigated gene variants was significantly more prevalent in BRVO patients than among control subjects, our data suggest that these polymorphisms themselves are unlikely major risk factors for BRVO.

TNF-alpha -308 G>A and -238 G>A polymorphisms are not major risk factors in Caucasian patients with exfoliation glaucoma.

PURPOSE: TNF-alpha has been suggested to participate in the pathogenesis of exfoliation glaucoma (XFG). The purpose of the present study was to investigate a hypothesized association between two common functional polymorphisms in the promoter region of the TNF-alpha gene (TNF-alpha -308 G>A, rs1800629, and TNF-alpha -238 G>A, rs361525) and the presence of XFG in a Caucasian population. METHODS: The present case-control study comprised 408 participants (204 patients with XFG and 204 control subjects). Control subjects were matched for age and sex. Genotypes of the TNF-alpha -308 G>A and TNF-alpha -238 G>A polymorphisms were determined by polymerase chain reaction (restriction fragment length polymorphism). RESULTS: No significant differences regarding genotype distribution or allelic frequencies were found between patients and control subjects (p>0.025). The presence of the TNF-alpha -308 G-allele was associated with an insignificant odds ratio of 0.98 (95% confidence interval [CI]: 0.66-1.46; p=0.99) while the presence of the TNF-alpha -238 G-allele was associated with an insignificant odds ratio of 0.64 (95% CI: 0.33-1.23; p=0.25). CONCLUSIONS: Our data suggest that both the TNF-alpha -308 G>A and the TNF-alpha -238 G>A polymorphisms are unlikely to be major risk factors for XFG in an European population of Caucasian descent.

Analysis of three pigment epithelium-derived factor gene polymorphisms in patients with exudative age-related macular degeneration.

PURPOSE: Exudative age-related macular degeneration (exudative AMD) is a common vision-threatening disease, with both environmental and genetic factors contributing to its development. Recently, homozygosity for the 72Met variant of the pigment epithelium-derived factor (PEDF) Met72Thr gene polymorphism (rs1136287) was identified as a novel risk factor for exudative AMD in Chinese patients from Taiwan. The role of this polymorphism, however, has not yet been determined in a white European population. In addition, two other PEDF gene polymorphisms, -5736T>C (rs12150053) and -5304C>T (rs12948385), have been associated with increased risk of diabetic retinopathy, but have not yet been studied among patients with exudative AMD. The purpose of the present study was thus to investigate a hypothesized association between these PEDF polymorphisms and the presence of exudative AMD in a white European population. METHODS: The present case-control study comprised 269 patients with exudative AMD and 155 control subjects. Genotypes of the PEDF polymorphisms were determined by 5'-exonuclease assays (TaqMan). RESULTS: PEDF genotype and allele frequencies were not significantly different between AMD patients and control subjects. The two promoter polymorphisms, -5736T>C (rs12150053) and -5304C>T (rs12948385), were in complete association. Presence of the homozygous PEDF 72 Met/Met genotype was associated with a nonsignificant odds ratio of 1.00 (95% confidence interval: 0.67-1.49, p=0.99). Similarly, presence of the homozygous PEDF -5736 TT genotype or -5304 CC genotype was associated with a nonsignificant odds ratio of 0.99 (95% confidence interval: 0.56 - 1.75, p=0.97). Both promoter polymorphisms were in linkage disequilibrium with the Met72Thr (rs1136287) polymorphism (D'=0.83) and formed three common and one rare haplotype. Haplotype frequencies were similar between AMD patients and control subjects (p>0.05). CONCLUSIONS: Our data suggest that none of the investigated PEDF polymorphisms is likely a major risk factor for exudative AMD in a white European population.

Determination of uric acid concentrations in human tear fluid, aqueous humour and serum.

PURPOSE: The aim of this investigation was to assess and compare levels of uric acid in human tear fluid, aqueous humour and serum in cataract patients in order to obtain information about uric acid-dependent antioxidative status. METHODS: Reflex tear fluid, aqueous humour and serum were obtained from 103 cataract patients (52 women, 51 men). Uric acid was determined by a reversed phase chromatographic method with electrochemical detection. The Randox test was used to measure the contribution of uric acid to the total antioxidative status (TAS) of these body fluids. RESULTS: Mean concentrations of uric acid were 20 +/- 8 microg/ml in tear fluid, 18 +/- 6 microg/ml in aqueous humour and 58 +/- 15 microg/ml in serum. Significantly less uric acid was found in tear fluid (p < 0.01) and aqueous humour (p < 0.01) in female cataract patients compared with male cataract patients. There was a significant positive correlation between uric acid content in tear fluid, aqueous humour and serum, respectively (p < 0.01). The contribution of uric acid to TAS (Randox test) amounted to 38% in tear fluid, 10% in aqueous humour and 37% in serum. CONCLUSIONS: Uric acid was found in comparable amounts in tear fluid and aqueous humour, but these were two- to threefold lower than in serum. Female cataract patients had lower uric acid values in tear fluid and aqueous humour compared with male cataract patients. Uric acid is an important antioxidant, as proven by its contribution to TAS as determined by the Randox test. The precise role of uric acid in the antioxidative reactions in tear fluid and aqueous humour is still under debate.

Plasminogen activator inhibitor-1 4G/5G gene polymorphism and primary open-angle glaucoma.

PURPOSE: Alterations of the plasmin system have been suggested to participate in the multifactorial pathogenesis of primary open-angle glaucoma (POAG). The main physiological inhibitor of the plasmin system is plasminogen activator inhibitor-1 (PAI-1), which leads to decreased degradation of extracellular material. Interestingly, elevated PAI-1 levels in the aqueous humor of patients with POAG have been reported. A common polymorphism within the promoter region (PAI-1 4G/5G) has previously been shown to reduce the gene transcription rate of PAI-1. The purpose of the present study was to investigate a hypothesized association between PAI-1 4G/5G and the presence of POAG in a Caucasian population. METHODS: The present case-control study comprised 212 unrelated patients with POAG and 212 healthy control subjects, matched for age and sex. Genotyping of PAI-1 4G/5G polymorphisms was done using polymerase chain reaction. RESULTS: Allelic frequencies and genotype distributions of PAI-1 4G/5G did not significantly differ between patients with POAG and control subjects (PAI-1 4G/5G: 29.7% versus 29.7%). Presence of the PAI-1 4G-allele was associated with a nonsignificant odds ratio of 0.98 (95% confidence interval: 0.74-1.30) for POAG. CONCLUSIONS: Our data suggest that PAI-1 4G/5G itself is unlikely to be a major risk factor among Caucasian patients with POAG.

Lysyl oxidase-like protein 1 (LOXL1) gene polymorphisms and exfoliation glaucoma in a Central European population.

PURPOSE: Exfoliation syndrome (XFS) is characterized by an accumulation of abnormal extracellular material in the anterior part of the eye that frequently leads to increased intraocular pressure and glaucomatous optic neuropathy. Recently, two non-synonymous polymorphisms (rs1048661 G>T and rs3825942 G>A) of lysyl oxidase-like protein 1 (LOXL1), a monoamine oxidase that catalyzes the polymerization of tropoelastin to elastin, were found to be associated with increased risk for XFS and exfoliation glaucoma (XFG). The aim of the present study was to investigate the role of these LOXL1 variants in a Central European cohort of Caucasian patients with XFG. METHODS: The present case-control study comprised of 167 unrelated patients with XFG and 170 control subjects. Genotyping of the LOXL1 rs1048661 and rs3825942 polymorphisms was done using polymerase chain reaction. RESULTS: The frequency of allele G of rs1048661 as well as rs3825942 was significantly higher in patients than in controls (rs1048661: 0.841 in patients versus 0.669; p<0.001; rs3825942: 0.994 in patients versus 0.817; p<0.001). Odds ratios of 52.1 (95% confidence interval [CI]: 13.85-195.6) and 14.67 (95% CI: 3.81-56.2), respectively, were calculated for the two high-risk haplotypes GG and TG compared to the haplotype GA. CONCLUSIONS: Our data confirm the previously reported association between LOXL1 polymorphisms and XFG and extend our knowledge to a Central European population.

Association of the HTRA1 -625G>A promoter gene polymorphism with exudative age-related macular degeneration in a Central European population.

PURPOSE: Exudative age-related macular degeneration (AMD) is one of the most common causes of severe visual loss. Both environmental and genetic factors, such as the complement factor H (CFH) 402H allele, have been associated with AMD. Recently, the HTRA1 -625A allele was identified as a novel risk marker in both a North American and a Chinese population. The present study was performed to evaluate the association of the HTRA1 -625A allele with exudative AMD in a Central European population. METHODS: The present case-control study included 242 patients with exudative AMD and 157 control subjects. Genotypes of the HTRA1 -625G>A polymorphism were determined by a 5'-exonuclease assay (TaqMan). Determination of CFH Y402H genotypes was done by allele specific digestion of polymerase chain products. RESULTS: Carriers of the HTRA1 -625AA genotype were found significantly more often in AMD patients than among control subjects (27.7% versus 5.1%; p<0.001). Binary logistic regression analysis binary logistic regression analysis revealed an odds ratio (OR) of 2.7 (95% confidence interval (CI): 1.1-6.8) for AMD among subjects heterozygous for the HTRA1 -625A allele compared to those with the wildtype genotype, when adjusted for CFH Y402H genotypes (p=0.034). The OR increased to 10.2 (95% CI: 3.0-34.5) among subjects homozygous for the HTRA1 -625A allele (p<0.001). The OR for AMD among heterozygous carriers of the CFH 402H variant was 3.6 (95% CI: 1.6-7.8) compared to those with the wildtype genotype, when adjusted for HTRA1 -625G>A genotypes (p=0.001). The OR increased to 9.8 (95% CI: 3.7-25.9) among subjects homozygous for the CFH 402HH genotype (p<0.001). Interaction terms between CFH and HTRA1 genotypes were not significantly associated with AMD. CONCLUSIONS: Our data suggest that both the HTRA1 -625A allele and the CFH 402H allele are independently associated with exudative AMD in a Central European population.

Low density lipoprotein triglycerides and lipoprotein(a) are risk factors for retinal vascular occlusion.

BACKGROUND: Retinal artery occlusion (RAO) and retinal vein occlusion (RVO) are common causes of severe visual loss and several atherothrombotic risk factors such as hyperlipidemia, diabetes mellitus and arterial hypertension have been associated with these ophthalmic lesions. METHODS: In this retrospective study we investigated 66 patients with RAO, 87 patients with RVO and 405 age- and gender-matched control subjects. Lipoproteins were separated using an ultracentrifugation-precipitation method (beta-quantification) and the levels of lipids and apolipoproteins in VLDL, LDL and HDL particles were measured. RESULTS: After adjusting for the type of occlusion and lipid-lowering medication, patients with RVO and RAO versus controls had significantly higher levels of LDL-cholesterol (3.82+/-1.06, 3.59+/-0.90 and 3.07+/-0.83 mmol/L), LDL-triglycerides (0.39+/-0.14, 0.40+/-0.12 and 0.35+/-0.14 mmol/L) and apolipoprotein B (1.06+/-0.27, 1.05+/-0.26 and 0.84+/-0.21 g/L) in the LDL fraction, respectively. In RAO, LDL-triglycerides were independently associated with retinal vascular occlusion. Interestingly, apolipoprotein AI was elevated in both patient groups compared to controls. The most striking differences were found in lipoprotein(a) where both RVO and RAO patients had significantly higher levels than the control subjects (median values: 320, 290 and 130 mg/L, respectively). CONCLUSION: These findings suggest that disorders in lipoprotein metabolism may contribute to the etiology of retinal vascular occlusions.

Association of complement factor H Y402H gene polymorphism with different subtypes of exudative age-related macular degeneration.

OBJECTIVE: Exudative age-related macular degeneration (AMD) is a common cause for a severe central visual loss. The complement system has been implicated in the pathogenesis of drusen. Recently, a complement factor H (CFH) polymorphism, which is characterized by a tyrosine (Y)-to-histidine (H) exchange at position 402 of the CFH gene, has been suggested as a major risk factor for AMD in a North American population. The aim of the present study was to investigate a hypothesized association between the CFH Y402H polymorphism and the presence of exudative AMD in a Central European population of Caucasoid descent as well as to determine the genotype distribution among different types of exudative AMD. DESIGN: Retrospective case-control study. PARTICIPANTS: The study cohort consisted of 179 patients with exudative AMD and 163 controls. METHODS: Determination of genotypes was carried out by allele-specific digestion of polymerase chain reaction products. MAIN OUTCOME MEASURES: Genotypes of CFH Y402H polymorphism. RESULTS: The prevalence of the CFH 402HH genotype was significantly higher in patients with exudative AMD than among controls (35.2% vs. 8.6%; P<0.001). Homozygosity for the CFH Y402H polymorphism was associated with an odds ratio of 5.78 (95% confidence interval, 3.09-10.83) for exudative AMD. Subgroup analysis revealed that the CFH 402HH genotype was significantly more prevalent in eyes with predominantly classic with no occult choroidal neovascularization (CNV) than in those with either retinal angiomatous proliferation, occult with no classic CNV, or predominantly classic with occult CNV. CONCLUSION: Our data suggest that the CFH Y402H polymorphism is a major risk factor for exudative AMD in a Central European population.