Анализ изменения концентрации цитокинов и хемокинов в стекловидном теле и субретинальной жидкости у пациентов с регматогенной отслойкой сетчатки (предварительные результаты)

To compare the concentration of amino acids in subretinal and vitreous fluid of patients with primary rhegmatogenous retinal detachment to that of control vitreous. This prospective, observational study measured amino-acid levels in subretinal fluid of patients undergoing scleral buckle placement (n=20) and vitreous fluid in patients undergoing pars plana vitrectomy (n=5) for primary retinal detachment. Vitreous fluid from patients undergoing vitrectomy for macular hole (n=7) or epiretinal membrane (n=3) served as a control. Subretinal fluid and control vitreous were analysed using high-pressure liquid chromatography. Retinal detachment vitreous was analysed using capillary electrophoresis-laser-induced fluorescence. Mean levels of glutamate (27.0+/-1.7 microM), aspartate (4.1+/-4.0 microM), and glycine (44.1+/-31.0 microM) in subretinal fluid and glutamate (13.4+/-11.9 microM) in the vitreous were significantly elevated in retinal detachment compared to control vitreous. A significant, positive association was observed between levels of aspartate and glutamate in subretinal fluid (Spearman's correlation coefficient: 0.74, P<0.01). Mean arginine levels did not differ significantly between subretinal fluid and control vitreous. Levels of alanine, tyrosine, valine, isoleucine, leucine, and phenylalanine were significantly lower in subretinal fluid compared to control vitreous (all P<0.01). Glutamate levels in subretinal fluid and vitreous of patients with primary retinal detachment is significantly elevated in comparison to control vitreous. This finding lends further support to the hypothesis that elevated glutamate levels may result from ischaemia of the outer retina secondary to retinal detachment.

TIMP-1 and TIMP-2 Levels in Vitreous and Subretinal Fluid

Purpose: To measure prothrombin fragments (F1+2) and thrombin-antithrombin complex (TAT) in vitreous and subretinal fluid (SRF) of rhegmatogenous retinal detachment (RRD) patients and to validate and further specify our earlier finding of increased thrombin activity in patients with proliferative vitreoretinopathy (PVR). Methods: F1+2 and TAT were measured in 31 vitreous and 16 SRF samples using the Enzygnost® immunoassays. Results: We found significant levels of F1+2 and TAT in the vitreous of all patients with RRD compared to patients with macular hole or macular pucker. However, there was no significant difference between patients who would develop PVR in the future, had established PVR, and patients with uncomplicated RRD both in vitreous concentrations of F1+2 (Kruskal-Wallis p = 0.963) and TAT (p = 0.516). Conclusion: The analysis of F1+2 and TAT confirmed significant thrombin generation in both vitreous and SRF of patients with RRD. An imbalance between the thrombin regulation mechanisms TAT and α2-macroglobulin possibly explains the difference from our previous findings.

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Purpose: To investigate whether rhegmatogenous retinal detachment (RRD) alters intraocular soluble syndecan-1 levels. Methods: In all, 39 samples of subretinal fluid (SRF) and 10 samples of vitreous fluid from RRD patients were collected. Using ELISA, soluble syndecan-1 levels were detected, and potential correlations between syndecan-1 levels with clinical parameters were analyzed. Results: Soluble syndecan-1 in the vitreous fluid (2.577 ± 0.578 ng/ml) and in the SRF (1.499 ± 0.184 ng/ml) from eyes with RRD enhanced significantly compared to that of the controls (0.224 ± 0.095 ng/ml) (p < 0.0001 and p = 0.006). An increase in the syndecan-1 concentrations in SRF samples correlated with a longer duration of retinal detachment (r = 0.716, p < 0.0001) and a younger age (r = −0.341, p = 0.017). Conclusions: RRD was found to be associated with a significant increase of soluble syndecan-1 in the vitreous fluid and SRF. In SRF, an enhanced soluble syndecan-1 concentration correlated positively with the duration of retinal detachment and inversely with the age of patients.

PurposeTo study the proteome of the subretinal fluid (SRF) from rhegmatogenous retinal detachment (RRD) in search for novel markers for improved diagnosis and prognosis of RRD.MethodsHuman undiluted SRF obtained during vitrectomy for primary RRD using a 41-gauge needle (n = 24) was analyzed and compared to vitreous humor from 2-day postmortem eyes (n = 20). Sample preparation underwent nanoflow liquid chromatography–tandem mass spectrometry. Label-free quantification (LFQ) using MaxQuant was used to determine differentially expressed proteins between SRF and vitreous humor. The intensity-based absolute quantification (iBAQ) was used to rank proteins according to their molar fractions within groups. Identification of proteins beyond the quantitative level was performed using the Mascot search engine.ResultsThe protein concentration of the control vitreous humor was lower and more consistent (1.2 ± 0.4 mg) than that of the SRF (17.9 ± 22 mg). The iBAQ analysis showed high resemblance between SRF and vitreous humor, except for crystallins solely identified in vitreous humor. The LFQ analysis found 38 protein misregulations between SRF and vitreous humor of which the blood coagulation pathway was found to be enriched using the PANTHER Classification System. Combined, the iBAQ, LFQ, and Mascot analysis found an overlap only in chitinase-3-like protein 1 and galectin-3-binding protein unique to the SRF.ConclusionsThe proteome of the SRF was highly represented by proteins involved in proteolysis. Such proteins can possibly serve as targets in modulating the effects of SRF in RD.Translational RelevanceTo identify potential novel biomarkers for therapeutic targeting in RD.

Concentration of vascular endothelial growth factor within the subretinal space and vitreous fluid in rhegmatogenous retinal detachment

An increased mRNA expression of genes related to blood coagulation has been demonstrated in an experimental retinal detachment model but has not yet been confirmed in human clinical specimens. Tissue factor (TF), the initiating factor of blood coagulation, may be a determinant of the extent of tissue injury after rhegmatogenous retinal detachment (RRD). This study was conducted to determine whether subretinal fluid and vitreous fluid collected from patients with RRD have a procoagulant effect. Calibrated thrombin generation (CAT) was used to investigate the thrombogenic properties of 28 subretinal fluids collected during scleral buckling surgery for RRD. Further, the thrombogenic properties of vitreous fluids from RRD (n = 12), macular pucker (n = 5), macular hole (n = 6), and proliferative diabetic retinopathy (n = 5) were compared with the properties of eye bank eyes (n = 11), which served as control specimens. The procoagulant activity of TF was determined with Western blot analysis. The addition of subretinal fluid from all RRD patients (28/28, 100%) induced thrombin generation in normal and severely factor (F)XII-deficient plasma. Contrary to the subretinal fluid, the addition of vitreous fluids from various ocular disorders evoked very little thrombin generation in normal and severely FXII-deficient plasma (4/12, 33% RRD; 1/5, 20% macular pucker; 0/6, 0% macular hole; 0/5, 0% proliferative diabetic retinopathy; and 2/11, 18% eye bank eyes). The procoagulant activity in subretinal fluid was almost completely neutralized by antibodies against human TF. The presence of TF in subretinal fluid was confirmed by Western blot. Subretinal fluid of patients with RRD induces high procoagulant activity, determined by measuring the level of tissue factor.

Obieetive To explore the relation between proliferative vitreous retinopathy after retinal detachment and Glu and GABA.Methods Patients were divided into the control group,non-PVR Group and the PVR group.The content of glutamate and Y-aminobutyric acid in the subretinal fluid (the vitreous for the control group)and blood were quantitatively detected using high pressure liquid chromatography.Results The differences of glutamate and Y-aminobutyric acid in the blood between the patients with retinal detachment and the control patients was not statistically significant.The content of glutamate in the subretinal fluid of patients with retinal detachment was higher than that in the vitreous of control patients,and the content of glutamate in the subretinal fluid of patients with proliferative vitreous retinopathy was higher than that of patients with non-proliferative vitreous retinopathy.The differences were statistically significant(F = 14.031,P ＜0.001).The content of Y-aminobutyric acid in the subretinal fluid of patients with retinal detachment was higher than that in the vitreous of control patients,and the content of Y-aminobutyric acid in the subretinal fluid of patients with proliferative vitreous retinopathy was higher than that of patients with non-proliferative vitreous retinopathy.The differences were statistically significant (F = 9.311,P = 0.001).The rate of glutamate and Y-aminobutyric acid in the subretinal fluid of patients with retinal detachment was higher than that in the vitreous of control patients,and the rate of glutamate and Y-aminobutyric acid in the subretinal fluid of patients with proliferative vitreous retinopathy was higher than that of patients with non-proliferative vitreous retinopathy.The differences were statistically significat(F = 4.411,P = 0.022).Conelussion The content of Y-aminobutyric acid in the subretinal fluid is not sufficient to antagonize the glutamate toxic effect in patients with retinal detachment,especial in patients with proliferative vitreous retiopathy,resulting in transmission functional disturbance of retinal neurons which affects the patients' visual function. Key words: Retinal detachment; Proliferative vitreous retinopathy; Glutamate ; Y-aminobutyric acid

To analyze whether preoperative duration of primary rhegmatogenous retinal detachment (RD) influences endothelin-1 (ET-1)--a vasoactive, mitogenic, and pro-apoptotic peptide- levels with repercussions on logarithmic (LogMAR) visual acuity (VA). Prospective clinical cohort study on 66 healthy patients [33 with proliferative vitreoretinopathy (PVR) and 33 with no PVR] with unilateral RD candidates for scleral buckling (SB) surgery. Using radioimmunoassay, immunoreactive ET-1 (IR-ET-1) was tested in both plasma and subretinal fluid (SRF) of these RD patients. Pearson's correlations were evaluated between preoperative RD duration and each IR-ET-1 level (plasma, SRF and the difference SRF minus plasma) and also between both variables and the LogMAR VAs (preoperative, postoperative 8 months, and the difference: postoperative 8 months minus preoperative). PVR was associated with higher preoperative RD duration, higher LogMAR VA values (pre- and postoperative 8 months) and higher IR-ET-1 values (plasma, SRF and the difference: SRF minus plasma) than no-PVR IR-ET-1 levels (plasma and SRF) were only correlated (r = 0.462, p = 0.007; r = 0.397, p = 0.022 respectively) with preoperative RD duration in the no-PVR group. IR-ET-1 values (plasma, SRF and the difference:SRF minus plasma) showed statistically significant correlations with pre- and with postoperative 8 months LogMAR VAs in no-PVR and with postoperative 8 months LogMAR VA and LogMAR VA difference in PVR The highest correlation between IR-ET-1 levels and LogMAR VAs was found between SRF IR-ET-1 and postoperative 8 months LogMAR VA in PVR (cases with macula-on) (r = 0.956, p < 0.0001). Preoperative RD duration showed statistically significant positive correlations with pre- and with postoperative 8 months LogMAR VAs in both the no-PVR and the PVR groups and with IR-ET-1 measurements (plasma and SRF: lower correlations) only in the no-PVR group. These findings support the idea of doing primary and prompt vitrectomy for RD and perhaps using coadjutant pharmacologic therapy in order to improve visual results.

The purpose of this study was to determine if the volume of subretinal fluid in patients with acute rhegmatogenous retinal detachment may be reduced through patient positioning before pneumatic retinopexy. This was a prospective, masked nonrandomized cohort study examining the change in subretinal fluid volume in patients with rhegmatogenous retinal detachment before and after a 1-hour period of specific head positioning, as measured using B-scan ultrasonography. A series of B-scans, each 2 mm apart in the sagittal plane, were acquired for each eye both before and after the positioning period with the patient lying in a supine position. Ten patients with acute unilateral rhegmatogenous retinal detachment were enrolled. All patients experienced a reduction in subretinal fluid volume, from a mean prepositioning volume of 0.89 ± 0.63 mL to a mean postpositioning volume of 0.45 ± 0.43 mL. The mean relative reduction in subretinal fluid measured as a percentage of prepositioning subretinal fluid volume was 55.4% ± 20%, ranging from 35.3% to 93.5%. In patients with acute rhegmatogenous retinal detachment that fall within the classic indications for pneumatic retinopexy, significant reduction of subretinal fluid volume may be obtained through a 1-hour period of patient positioning in a retinal break-dependent manner.

Background: Cyclic guanosine monophosphate (cGMP) is produced in different retinal cells, including photoreceptor cells, wherein cGMP mediates photo-transduction. CGMP is degraded by phosphodiesterases (PDE). The aim was to investigate whether...

Evidence suggests that there is a net movement of fluid through the retinal break in eyes with rhegmatogenous retinal detachment, this net movement being directed from the vitreous humour into the subretinal space. However, it remains uncertain how much fluid exchange occurs in both directions across such breaks. The concentration ratios of IgG/IgM or IgA/IgM, derived from assay of immunoglobulins in vitreous humour, subretinal fluid, and serum from a group of 19 such patients, suggest a lack of free, two-directional, fluid movement across the retinal break. Furthermore the IgG/IgM ratios for the two intraocular fluids were significantly greater than that of serum, this suggesting that these intraocular fluids are formed, at least in part, by a selective transduction of serum.

To explore the effect of glucosamine (GlcN) on transforming growth factor (TGF)-β signalling and several processes involved in proliferative vitreoretinopathy (PVR). We evaluated the surface levels of TGF-β receptor and its binding of TGF-β in ARPE-19 cells. Release of cytokines and collagen, and expression of signalling intermediates were quantified. Migration was qualitatively and quantitatively examined. The morphology of cells undergoing PVR in vitro and in a mouse PVR model was observed. Glucosamine reduced the surface levels of TGF-β receptor and the ability of ARPE-19 cells to bind TGF-β. In ARPE-19 cells, TGF-β1 plus epidermal growth factor (EGF) or TGF-β2 increased the expression of alpha-smooth muscle actin (α-SMA) and decreased the expression of zona occludens protein (ZO-1). Transforming growth factor-(β2) also caused the release of platelet-derived growth factor (PDGF), connective tissue growth factor (CTGF) and type 1 collagen and increased the phosphorylation of SMAD2 and SMAD3. Platelet-derived growth factor and CTGF stimulated cell migration, and TGF-β2 stimulated wound closure, contraction of collagen and changes in cell morphology. Treatment with GlcN counteracted all of these effects, and its administration in the mouse model reduced the morphologic appearance of PVR. Glucosamine could inhibit the TGF-β signalling pathway in retinal pigment epithelium cells and several of the downstream events associated with epithelial-mesenchymal transition and PVR.

Biochemical analyses of subretinal fluid revealed a consistently high ascorbate level in the subretinal fluid of patients with rhegmatogenous retinal detachment. The average values and SDs of ascorbate in anterior chamber aqueous humor, subretinal fluid, and blood were 14.7 +/- 1.8, 27.4 +/- 2.1, and 1.8 +/- 0.2 mg/dL, respectively. The ascorbate concentration in subretinal fluid was always higher than that in aqueous humor. The high ascorbate level in subretinal fluid led to the hypothesis that aqueous humor contributes to the formation of subretinal fluid. Presumably and constant absorption of subretinal fluid by the choroid directs a portion of the aqueous humor from the posterior chamber into the subretinal space. The posterior movement of aqueous humor causes reduced ascorbate concentration in the anterior chamber and relative hypotony of eyes with rhegmatogenous retinal detachment. Closing the retinal break results in an interruption of the posterior movement of aqueous humor and rapid absorption of the remaining subretinal fluid by the choroid.