Proliferative and inflammatory factors in the vitreous of patients with proliferative diabetic retinopathy

Purpose:

The purpose was to measure the concentrations of various cytokines and growth factors (including vascular endothelial growth factor [VEGF] and pigment epithelium-derived factor [PEDF]) in the vitreous of patients with proliferative diabetic retinopathy (PDR) and to investigate interaction between inflammatory and proliferative factors in the genesis of PDR.

Materials and Methods:

Vitreous samples from 32 eyes with PDR and 25 eyes without diabetes mellitus and signs of DR (control) were collected. Vitreous concentrations of VEGF, PEDF, monocyte chemotactic protein-1 (MCP-1), interleukin-4 (IL-4), IL-6, IL-8, IL-10, IL-17A, and secretory immunoglobulin A (sIgA) were simultaneously measured using enzyme-linked immunoassay.

Results:

Vitreous levels of VEGF, PEDF, IL-17A, IL-6, IL-8, IL-4, and sIgA were significantly (Π < 0.05) higher in eyes with PDR compared to control. The concentration of VEGF was more than 17-times higher than in control, and the concentration of PEDF was not changed oppositely and was also higher (1.45-times) compared to control, that may indicate disturbances of compensatory mechanisms in angiogenesis regulation in PDR. Significant (P < 0.05) positive correlations were observed between vitreous concentrations of VEGF and IL-17A (r = 0.45), VEGF and IL-8 (r = 0.48), VEGF and IL-4 (r = 0.51), PEDF and IL-17A (r = 0.48), PEDF and IL-8 (r = 0.59), MCP-1 and PEDF (r = 0.72), MCP-1 and IL-8 (r = 0.45), IL-4 and IL-17A (r = 0.65), IL-4 and IL-8 (r = 0.71), IL-8 and IL-17A (r = 0.59).

Conclusions:

Significantly raised levels of inflammatory and proliferative factors and numerous positive correlations between them may demonstrate a significant role of activation of vascular proliferation and local inflammation in the pathogenesis of PDR.     

玻璃体腔注射Bevacizumab对PDR患者增殖膜中CTGF及PEDF的影响

目的:研究增殖性糖尿病视网膜病变(PDR)玻璃体腔注射抗-VEGF药物bevacizumab后对增殖膜中结缔组织生长因子(CTGF)及色素上皮衍生因子(PEDF)的影响.方法:回顾2015-01/2016-12入本院行增殖性糖尿病视网膜病变治疗的患者117例126眼,采用病例对照的研究方法,将所选病例随机分为两组,分别为A组60例63眼和B组57例63眼.其中A组单纯进行玻璃体切割手术,B组患者在玻璃体切割术前玻璃体腔注射0.05mL/1.25mg bevacizumab.在手术中剥离取用两组患者的视网膜增殖膜进行染色,然后进行组织病理学观察,观察两组患者视网膜增殖膜中原始细胞和新生血管的变化,以及患者增殖膜中CTGF和PEDF因子的表达.结果:在对两组患者CTGF、PEDF因子表达进行观察发现,两组患者视网膜增殖膜中的CTGF和PEDF都在细胞质内表达.其中A组呈现出38眼阳性表达,阳性表达率为60.3%,相比于A组而言,B组的CTGF的阳性表达率92.1%明显更高,两组差异有统计学意义(P<0.05).而两组的PEDF阳性表达率分别为90.5%和95.2%,差异无统计学意义(P>0.05).结论:PDR患者在玻璃体腔注射抗VEGF药物bevacizumab后,视网膜的新生血管明显减少,有利于玻璃体切割手术的进行.且PDR患者玻璃体腔注射bevacizumab后,CTGF的阳性表达率明显增高,而PEDF因子在前膜上的表达则没有明显的变化.     

Soluble IL-6 Receptor in Vitreous Fluid of Patients with Proliferative Diabetic Retinopathy

Purpose

To identify the biological reaction of soluble interleukin-6 receptor (sIL-6R) in the vitreous of patients with proliferative diabetic retinopathy (PDR).

Methods

The subjects were 45 patients (45 eyes) with vitreoretinal diseases. The patients were divided into three groups: the PDR group comprised 28 patients (28 eyes) with PDR; the pre-proliferative diabetic retinopathy (PPDR) group comprised seven patients (seven eyes) with PPDR combined with diabetic macular edema; and the nondiabetic group comprised ten patients (ten eyes) with idiopathic macular hole or idiopathic epiretinal membrane. Vitreous samples were obtained at vitrectomy. sIL-6R, vascular endothelial growth factor (VEGF), and protein concentration in vitreous samples were determined by enzyme-linked immunosorbent assay (ELISA). sIL-6R levels in serum were also determined by ELISA in nine of the 28 patients with PDR and in six healthy volunteers as controls.

Results

In vitreous fluid, the levels of sIL-6R in the PDR group, PPDR group, and nondiabetic group were 612.7 ± 233.8 (mean ± SD), 746.3 ± 523.1, and 215.4 ± 98.3?pg/ml, respectively. Vitreous levels of sIL-6R in the PDR and PPDR groups were significantly higher than those in the nondiabetic group (PDR group, P < 0.0001; PPDR group, P < 0.01). In serum, the levels of sIL-6R were 39.38 ± 9.43?ng/ml in the PDR group and 22.84 ± 5.32?ng/ml in the control group. sIL-6R levels in serum in the PDR group were significantly higher than those in the control group (P < 0.01). A partial correlation analysis showed a significant correlation between the levels of sL-6R and VEGF in the vitreous in the PDR group (r = 0.34, P < 0.05).

Conclusions

We conclude that the level of sIL-6R in vitreous fluid can be considered as a biomarker of PDR.?Jpn J Ophthalmol 2007;51:100–104 © Japanese Ophthalmological Society 2007

     

Alteration of intraocular pigment epithelium-derived factor and vascular endothelial growth factor in patients with diabetic retinopathy

AIM:b To determine the aqueous, vitreous, serum levels of pigment epithelium-derived factor (PEDF) and vascular endothelial growth factor (VEGF) in patients with proliferative diabetic retinopathy (PDR), and to speculate on the source of the change in concentration and to discuss its clinical significance. METHODS:b Forty-one eyes with proliferative diabetic retinopathy were included in the study, 16 of which were complicated by neovascularization of iris (NVI). Twenty-one eyes with idiopathic macular hole (MH) were as controls. The aqueous,vitreous, serum levels of PEDF and VEGF of all the groups were determined with ELISA. PEDF, VEGF and the levels in the three groups were compared with analysis of variance(ANOVA). The PEDF, VEGF concentrations in aqueous,vitreous and serum were analyzed with Pearson correlation test, and the correlation of PEDF and VEGF levels was also analyzed with Pearson correlation test. RESULTS:b The aqueous levels of PEDF decreased significantly in sequence in groups of control, PDR without NVI,PDR with NVI. VEGF levels increased coordinately. The similar findings existed in vitreous samples. The PEDF, VEGF levels in aqueous were not correlated significantly with those in serum, but correlated positively with those in vitreous. The intraocular levels of PEDF had a negative correlation to those of VEGF. CONCLUSION:b The reduction of intraocular PEDF level and elevation of intraocular VEGF level may play an important role in the occurrence and progression of PDR. In the development of PDR, the PEDF,VEGF levels in aqueous may be mainly effected by local pathological changes, as anti-angiogenic and pro-angiogenic factors, their unbalanced intraocular distribution may promote the angiogenesis of the iris and retina.     

Expression of pigment epithelium derived factor and vascular endothelial growth factor in choroidal neovascular membranes and polypoidal choroidal vasculopathy

AIMS: To determine whether pigment epithelium derived factor (PEDF), a protein that inhibits angiogenesis, is expressed in human choroidal neovascular membranes (CNVMs) and in tissues from an eye with polypoidal choroidal vasculopathy (PCV). In addition, to compare the expression of PEDF with that of vascular endothelial growth factor (VEGF), a known stimulator of angiogenesis, in these tissues. METHODS: CNVMs, associated with age related macular degeneration (AMD), angioid streaks, and PCV, were obtained during surgery. The expression of PEDF and VEGF in the excised subretinal fibrovascular membranes was determined by immunohistochemistry. RESULTS: PEDF and VEGF were strongly expressed in the vascular endothelial cells and retinal pigment epithelial (RPE) cells in the CNVMs where numerous new vessels were prominent (clinically active CNVMs). On the other hand, immunoreactivity for PEDF and VEGF was weak in the new vessels where fibrosis was prominent (clinically quiescent CNVMs). However, the RPE cells were still positive for PEDF and VEGF. The specimens from the eye with PCV also showed strong expression of PEDF and VEGF in the vascular endothelial cells and the RPE cells. CONCLUSION: Because PEDF is an inhibitor of ocular angiogenesis and an inhibitor of ocular cell proliferation, our results suggest that PEDF along with VEGF may modulate the formation of subfoveal fibrovascular membranes.     

Elevation of serum apelin-13 associated with proliferative diabetic retinopathy in type 2 diabetic patients

AIM:To compare apelin-13, a ligand of G-protein-coupled receptor which has been shown to be involved in retinal angiogenesis, and vascular endothelial growth factor (VEGF) serum levels in type 2 diabetes mellitus (T2DM) with or without retinopathy, and to investigate the relationship between the serum concentration of apelin-13 and diabetes retinopathy.METHODS: Sixty-nine patients with T2DM were enrolled. Of the 69 patients, 16 had proliferative diabetic retinopathy (PDR group), 23 had non-PDR (NPDR group) and 30 had no retinopathy (T2DM group). Subjects’ information, including demographics, medical history, and use of medications were recorded. Their serum samples were collected for measuring the levels of C-reactive protein (CRP), serum lipid and glycosylated hemoglobin. Apelin-13 and VEGF serum levels were measured by enzyme-linked immunosorbent assay. Kruskal-Wallis test and one-way ANOVA were used to compare the differences among these groups. Chi-square test was used to assess categorical variables. Correlations between variables were investigated by Spearman rho correlation test and stepwise regression analysis. All statistical analyses were performed through SPSS 17.0 software.RESULTS:Sex, age, body mass index (BMI), blood pressure, CRP, hemoglobin A1c (HbA1c) have no significantly difference in the three groups. Serum level of apelin-13 was significantly elevated in PDR group as compared with T2DM group (P=0.041). Differences of VEGF serum concentration in the three groups were statistically significant (P=0.007, P=0.007 and P<0.001, respectively). Spearman rho correlation test showed that serum apelin-13 was positively correlated with BMI, serum triglycerides, VEGF, but not with age, duration of diabetes, blood pressure, CRP, HbA1c and total-cholesterol. Stepwise regression analysis showed that BMI also significantly associated with serum apelin-13 (P=0.002), while VEGF and serum triglycerides were irrelevant.CONCLUSION: This study elucidated a positive association of apelin-13 serum level with PDR, but not with VEGF. Apelin-13 may influence the promotion of PDR but unrelated with VEGF.     

Retinal heparanase expression in streptozotocin-induced diabetic rats

Objective: Heparanase, an endoglycosidase, exhibits strong proangiogenic capacity that can induce vascular endothelial growth factor (VEGF) expression in tumour angiogenesis. The purpose of this study was to evaluate heparanase expression and its relationship with VEGF in streptozotocin (STZ)-induced diabetic rats' retinas.Design: Experimental study.Participants: STZ-induced rats and non-diabetic control rats.Methods: Heparanase expression was initially evaluated in cultured human retinal microvascular endothelial cells (HRECs) under high-glucose conditions by Western blot. Diabetes was induced in Sprague-Dawley rats by STZ intraperitoneal injection. Retinal heparanase expression was assayed in rats by immunohistochemistry. Heparanase inhibitor (phosphomannopentaose sulfate) was administrated to high-glucose-treated HRECs and diabetic rats. VEGF levels were evaluated in HRECs and retinas using enzyme-linked immunosorbent assay.Results: Heparanase expression was increased in HRECs under high-glucose conditions compared with controls (p < 0.01). Immunohistochemical studies indicated that heparanase signals were intense in the retinal vascular endothelia of diabetic rats, but faint in those of nondiabetic control rats. Quantitative analysis showed that heparanase protein expression was increased by 3.2-fold in diabetic rats' retinas compared with nondiabetic rats' retinas (p < 0.01). VEGF level was increased, as was heparanase expression, in high-glucose-treated HRECs and in the retinas of diabetic rats, and these increases were significantly decreased by phosphomannopentaose sulfate administration (p < 0.01).Conclusions: Heparanase expression was upregulated and associated with an increase of VEGF expression in STZ-induced diabetic rat retinas. The data suggest that heparanase may be involved in the development of diabetic retinopathy and represents a possible novel target for therapeutic intervention.     

Feasibility Study on Computer-Aided Screening for Diabetic Retinopathy

Purpose

To conduct a feasibility study of computer-aided screening for diabetic retinopathy by developing a computerized program to automatically detect retinal changes from digital retinal images.

Methods

The study was carried out in three steps. Step 1 was to collect baseline retinal image data of 600 eyes of normal subjects with normal fundi and data of 300 eyes of diabetic patients with diabetic retinopathy. All data were recorded by digital fundus camera. Step 2 was to analyse all retinal images for normal and abnormal features. By this method, the automated computerized screening program was developed. The program preprocesses colour retinal images and recognizes the main retinal components (optic disc, fovea, and blood vessels) and diabetic features such as exudates, haemorrhages, and microaneurysms. All of the accumulated information is interpreted as normal, abnormal, or unknown. Step 3 was to evaluate the sensitivity and specificity of the computerized screening program by testing the program on diabetic patients and comparing the program's results with the results of screening by retinal specialists.

Results

Diabetic patients (182 patients, 336 eyes) were examined by retinal specialists; 221 eyes had a normal fundus and 115 eyes had nonproliferative diabetic retinopathy. Digital retinal images were taken of these 336 eyes and interpreted by the automated screening program. The program had a sensitivity and specificity of 74.8% and 82.7%, respectively.

Conclusions

The automated screening program was able to differentiate between the normal fundus and the diabetic retinopathy fundus. The program may be beneficial for use in screening for diabetic retinopathy. Further development of the program may provide higher sensitivity.?Jpn J Ophthalmol 2006;50:361–366 © Japanese Ophthalmological Society 2006     

Clinical and histological features of epiretinal membrane after diabetic vitrectomy

Purpose

To investigate the clinical, histopathological, and surgical features of the epiretinal membrane (ERM) after diabetic vitrectomy (DV).

Methods

From August 2007 to January 2010, clinical charts of consecutive proliferative diabetic retinopathy (PDR) cases with significant post-DV ERM, defined as thickened membrane causing macular distortion and vision decrease, were enrolled as the study group; PDR cases without post-DV ERM in 24 months follow-up served as the control group. Factors associated with post-DV ERM formation, morphological and visual changes before and after ERM surgery, and histopathological features were analyzed.

Results

Sixteen eyes were in the ERM group, while 60 eyes were in the control group. Active PDR (p?<?0.001), fibrovascular proliferation (FVP) grade (p?=?0.001), post-DV hemorrhage (p?=?0.012), and residual fibrovascular stump (p?=?0.002) were factors significantly associated with post-DV ERM. Most membranes (87.5 %) developed within 12 months, were widespread beyond the arcade (81.3 %), and connected with retinal vessels (87.5 %). After surgery, significant VA improvement was achieved. ERM recurrence was noted in six eyes (37.5 %). Histopathological examinations of ERMs in six cases showed abundant collagen fibers with epithelial cells. Immunohistochemical staining with CD 34 demonstrated the presence of vascular endothelium in two of the six specimens.

Conclusion

The post-DV ERM is a complex tissue with variable vascularity that often presents with widespread distribution, rapid progression, and causes macular distortion. Associated risk factors include active PDR, high FVP grade, post-DV hemorrhage, and residual fibrovascular stumps. Membrane removal surgery may be beneficial in selected cases, but recurrence is not uncommon.     

Effect of pan-retinal laser photocoagulation on plasma VEGF, endothelin-1 and nitric oxide in PDR

AIM: To study plasma levels of vascular endothelial growth factor (VEGF), endothelin-1(ET-1) and nitric oxide (NO) in patients with proliferative diabetic retinopathy (PDR) before and after pan-retinal photocoagulation (PRP). · METHODS: Forty patients (23 females and 17 males, mean age 48.5±12.2 years) with PDR without previous PRP therapy were studied. Blood samples were obtained before and 3 months after the last PRP session. Baseline (prelaser) plasma levels of VEGF, ET-1 and NO were compared with their levels in 30 healthy age- and sex- matched controls and also with plasma levels 3 months post-PRP. · RESULTS: Patients with PDR had significantly raised plasma VEGF (375±89ng/L), ET-1(20±5ng/L) and NO (135±53μmol/L) when compared with healthy control group (P <0.01). After PRP, there was a significant reduction in plasma VEGF (179±66ng/L), ET-1 (11±5ng/L) and NO (91±49μmol/L) levels at 3 months' follow-up but still significantly higher than healthy controls. · CONCLUSION: Patients with PDR demonstrate elevated VEGF, ET-1 and NO, which decrease after successful laser treatment.     

Myeloid-Related Protein-14/MRP-14/S100A9/Calgranulin B is Associated with Inflammation in Proliferative Diabetic Retinopathy

Purpose: To investigate the expression of the leukocyte proteins myeloid-related protein (MRP)-8 and MRP-14 in proliferative diabetic retinopathy (PDR) and the effect of MRP-8/MRP-14 (calprotectin) heterodimer on induction of proinflammatory factors in human retinal microvascular endothelial cells (HRMEC).

Methods: Epiretinal membranes from 20 patients with PDR and 10 patients with proliferative vitreoretinopathy (PVR), vitreous fluid samples from PDR and non-diabetic subjects and HRMEC were studied by immunohistochemistry and Western blot analysis.

Results: MRP-14 expression was localized in endothelial cells, leukocytes and myofibroblasts in all PDR membranes. MRP-8 expression was limited to intravascular leukocytes in 42% of the studied membranes. In PVR membranes, MRP-14 was expressed in leukocytes and myofibroblasts, whereas MRP-8 immunoreactivity was limited to leukocytes. MRP-14 was significantly upregulated in vitreous from PDR patients. MRP-8/MRP-14 (calprotectin) increased expression of intercellular adhesion molecule-1, but attenuated vascular cell adhesion molecule-1 expression in HRMEC.

Conclusions: Increased MRP-14 levels are associated with inflammation in PDR.     

Correlation of complement fragment C5a with inflammatory cytokines in the vitreous of patients with proliferative diabetic retinopathy

Purpose

To determine the vitreous concentration of complement fragment C5a in patients with proliferative diabetic retinopathy (PDR) and the relation between C5a and inflammatory cytokines including vascular endothelial growth factor (VEGF) and monocyte chemotactic protein-1 (MCP-1).

Methods

Vitreous samples were obtained at the time of vitrectomy from 12 eyes of 11 PDR patients and from 11 eyes of 11 patients without diabetes with macular disease (controls). Vitreous and serum concentrations of human C5a, VEGF, and MCP-1 were quantified using FACS Caliber® flow cytometer.

Results

Vitreous concentration of C5a increased significantly in patients with PDR [median (range): 928.7 (46.6 to 3,319.4) pg/ml] compared with controls [58.7 (22.2 to 1,432.4) pg/ml; p?<?0.01]. In PDR patients, vitreous concentration of C5a correlated significantly with those of VEGF (p?<?0.05) and MCP-1 (p?<?0.05).

Conclusions

Our results suggest that C5a may play an important role in the pathogenesis of PDR and work in concert with inflammatory cytokines such as VEGF and MCP-1 in pathological angiogenesis.     

Increased levels of vascular endothelial growth factor in the aqueous humor of patients with diabetic retinopathy

Purpose:

This study aims to investigate the levels of aqueous vascular endothelial growth factor (VEGF) in diabetic patient groups in comparison to normal subjects, and to correlate elevated VEGF with the severity of diabetic retinopathy (DR).

Materials and Methods:

Aqueous samples were obtained from 78 eyes of 74 patients undergoing intraocular surgery and they were examined by the enzyme-linked immunosorbent assay. Color photographs, optical coherence tomography scans, and fluorescein angiography were used to evaluate patients preoperatively.

Results:

A strong statistical correlation was found to exist between the level of aqueous VEGF and the severity of DR (P < 0.001), whereas, the VEGF levels in a control group and a diabetic group without DR were not significantly different (P = 0.985). Aqueous VEGF levels were significantly elevated in patients with proliferative DR (PDR) as compared to the control group (P < 0.001), to diabetic patients without retinopathy (NDR) (P < 0.001), and to diabetic patients with nonproliferative DR (NPDR) (P < 0.001). The aqueous VEGF levels were significantly higher in patients with active PDR than in those with quiescent PDR (P = 0.001). On the other hand, a statistically insignificant (P = 0.065) correlation was found between elevated aqueous VEGF and the presence of macular edema in the NPDR group.

Conclusions:

VEGF was elevated in the aqueous humor of patients with DR compared to that in normal eyes. The aqueous VEGF level had a strong correlation with the severity of retinopathy along with a statistically insignificant difference in macular edema.     

Increased intravitreous interleukin-18 correlated to vascular endothelial growth factor in patients with active proliferative diabetic retinopathy

Purpose

To determine the intravitreous levels of interleukin-18 (IL-18) and vascular endothelial growth factor (VEGF) in patients with proliferative diabetic retinopathy (PDR) and to ascertain their association with PDR activity.

Methods

Thirty eyes of 30 diabetic patients with PDR were divided into two groups (active PDR, n?=?17; quiescent PDR, n?=?13). Fifteen eyes of 15 non-diabetic patients (macular hole, n?=?9; epiretinal membrane, n?=?6) served as controls. All vitreous fluid samples were obtained during vitrectomy. IL-18 and VEGF were measured by enzyme-linked immunosorbent assay. Serum glycosylated hemoglobin as well as the basic demographic data was documented.

Results

Both IL-18 and VEGF levels were higher in patients with PDR than control (P?<?0 .01 and P?<?0 .01, respectively). Both IL-18 and VEGF in active PDR were higher than those in quiescent PDR (P?=?0.048 and P?=?0.03, respectively). A significant positive correlation (Spearman rank correlation coefficient (r _s)?=?0.502, P?=?0.005) between IL-18 and VEGF was observed in all PDR patients but not in the control. The correlation between VEGF and IL-18 was even stronger in the subgroup of active PDR (r _s?=?0.684; P?=?0.002), whereas no significant correlation was found in the subgroup of quiescent PDR (r _s?=?0.049; P?=?0.873).

Conclusions

Both intravitreous IL-18 and VEGF were elevated in patients with PDR, which were closely correlated in active PDR. IL-18 may contribute to retinal angiogenesis by acting together with or via VEGF, and become the potential therapeutic target for treatment of PDR.     

CD146/Soluble CD146 Pathway Is a Novel Biomarker of Angiogenesis and Inflammation in Proliferative Diabetic Retinopathy

PurposeInflammation, angiogenesis and fibrosis are pathological hallmarks of proliferative diabetic retinopathy (PDR). The CD146/sCD146 pathway displays proinflammatory and proangiogenic properties. We investigated the role of this pathway in the pathophysiology of PDR.MethodsVitreous samples from 41 PDR and 27 nondiabetic patients, epiretinal fibrovascular membranes from 18 PDR patients, rat retinas, human retinal microvascular endothelial cells (HRMECs) and human retinal Müller glial cells were studied by ELISA, Western blot analysis, immunohistochemistry and immunofluorescence microscopy analysis. Blood-retinal barrier breakdown was assessed with fluorescein isothiocyanate-conjugated dextran.ResultssCD146 and VEGF levels were significantly higher in vitreous samples from PDR patients than in nondiabetic patients. In epiretinal membranes, immunohistochemical analysis revealed CD146 expression in leukocytes, vascular endothelial cells and myofibroblasts. Significant positive correlations were detected between numbers of blood vessels expressing CD31, reflecting angiogenic activity of PDR, and numbers of blood vessels and stromal cells expressing CD146. Western blot analysis showed significant increase of CD146 in diabetic rat retinas. sCD146 induced upregulation of phospho-ERK1/2, NF-κB, VEGF and MMP-9 in Müller cells. The hypoxia mimetic agent cobalt chloride, VEGF and TNF-α induced upregulation of sCD146 in HRMECs. The MMP inhibitor ONO-4817 attenuated TNF-α-induced upregulation of sCD146 in HRMECs. Intravitreal administration of sCD146 in normal rats significantly increased retinal vascular permeability and induced significant upregulation of phospho-ERK1/2, intercellular adhesion molecule-1 and VEGF in the retina. sCD146 induced migration of HRMECs.ConclusionsThese results suggest that the CD146/sCD146 pathway is involved in the initiation and progression of PDR.     

Expression of hypoxia-inducible factor-1alpha and the protein products of its target genes in diabetic fibrovascular epiretinal membranes

AIMS: To investigate the expression of the hypoxia-inducible factor-1alpha (HIF-1alpha) and the protein products of its target genes vascular endothelial growth factor (VEGF), erythropoietin (Epo) and angiopoietins (Angs), and the antiangiogenic pigment epithelium-derived factor (PEDF) in proliferative diabetic retinopathy (PDR) epiretinal membranes. METHODS: Sixteen membranes were studied by immunohistochemical techniques. RESULTS: Vascular endothelial cells expressed HIF-1alpha, Ang-2 and VEGF in 15 (93.75%), 6 (37.5%) and 9 (56.25%) membranes, respectively. There was no immunoreactivity for Epo, Ang-1 and PEDF. There were significant correlations between the number of blood vessels expressing the panendothelial marker CD34 and the numbers of blood vessels expressing HIF-1alpha (r = 0.554; p = 0.026), Ang-2 (r = 0.830; p<0.001) and VEGF (r = 0.743; p = 0.001). The numbers of blood vessels expressing Ang-2 and VEGF in active membranes were higher than that in inactive membranes (p = 0.015 and 0.028, respectively). CONCLUSIONS: HIF-1alpha, Ang-2 and VEGF may play an important role in the pathogenesis of PDR. The findings suggest an adverse angiogenic milieu in PDR epiretinal membranes favouring aberrant neovascularisation and endothelial abnormalities.     

眼内液中PEDF、VEGF含量变化对糖尿病视网膜病变的意义

目的:测定增殖型糖尿病视网膜病变(PDR)患者房水、玻璃体及血清中色素上皮源性因子(PEDF)、血管内皮生长因子(VEGF)的浓度变化,并探讨其变化的来源及临床意义.方法:以41只糖尿病视网膜病变患眼为研究对象,其中16只继发虹膜新生血管(NVI),21只特发性黄斑裂孔(MH)患眼作为对照.应用酶联免疫吸附法(ELISA),分别测定3组患眼房水、玻璃体、血清中PEDF、VEGF的质量浓度.采用单因素方差分析比较3组房水、玻璃体、血清中PEDF及VEGF的水平,采用Pearson相关性检验分析房水中PEDF、VEGF水平与血清、玻璃体中的关系,并分别分析3种眼内液中PEDF与VEGF的关系.结果:房水中PEDF浓度在对照组、PDR无继发NVI组、PDR继发NVI组依次降低,VEGF浓度依次升高,玻璃体中PEDF、VEGF浓度具有类似的变化趋势.房水PEDF、VEGF水平与血清的无明显相关性,与玻璃体的呈一定正相关性.眼内液中PEDF浓度与VEGF浓度呈负相关.结论:眼内液PEDF水平降低、VEGF水平升高可能对PDR的发生、发展起到重要作用.PDR发展过程中,房水中这两种因子的浓度变化可能主要受眼局部病变影响.PEDF、VEGF分别作为血管抑制因子和血管刺激因子的代表,其眼内分布失衡可能是促成NVI及视网膜新生血管发生的重要因素.     

VEGF localisation in diabetic retinopathy

AIM—To determine the staining pattern of vascular endothelial growth factor (VEGF) at different stages of diabetic retinopathy (including post-laser photocoagulation) and to compare staining in excised fibrovascular and fibrocellular (non-diabetic) preretinal membranes.
METHODS—Immunohistochemical localisation of VEGF, using antibodies raised against VEGF₁₆₅ and VEGF_121,165,189, was carried out on specimens of normal human retina (n=15), diabetic retinas ((a) with no overt retinopathy (n=19), (b) with intraretinal vascular abnormalities but no proliferative retinopathy (n=6), (c) with active proliferative retinopathy (n=6), (d) with no residual proliferative retinopathy after photocoagulation therapy (n=15)), excised diabetic fibrovascular membranes (n=19), and non-diabetic fibrocellular membranes (n=7). The degree and pattern of immunostaining was recorded.
RESULTS—In general, VEGF was absent from the majority of normal retinas. VEGF staining was apparent in most diabetic tissues but the staining pattern was dependent on both the specificity of the antibody used and the category of tissue. Staining with the VEGF₁₆₅ antibody was generally confined to endothelial cells and perivascular regions while the VEGF_121,165,189 antibody was also associated with extravascular components of the inner retina. Intensity of immunostaining of diabetic eyes was dependent on the severity of retinopathy being least in diabetics with no overt retinopathy and greatest in retinas with proliferative retinopathy. Interestingly, the intensity of immunostaining in diabetic retinas which had undergone laser surgery for proliferative retinopathy was reduced to basal levels. Moderate to intense immunostaining was observed in all fibrovascular and fibrocellular membranes examined.
CONCLUSIONS—This study supports a circumstantial role for VEGF in the pathogenesis of both the preclinical and proliferative stages of diabetic retinopathy.

Keywords: vascular endothelial growth factor; VEGF; diabetes; diabetic retinopathy     

VEGF和PEDF在增殖性糖尿病视网膜病变中的研究进展

增殖性糖尿病视网膜病变( proliferative diabetic retinopathy,PDR)是一种以眼内新生血管形成为特征的糖尿病并发症。眼内新生血管的形成是当今世界主要致盲原因之一。血管内皮生长因子( vascular endothelial growth factor,VEGF)与色素上皮衍生因子( pigment epithelium-derived factor,PEDF)作为眼内新生血管形成最主要的细胞因子,近年来成为研究热点。本文就VEGF和PEDF在PDR中的研究进展进行综述。     

25G玻璃体切割术联合不同抗VEGF药物治疗PDR的疗效比较

目的：探讨25G玻璃体切割术联合不同抗血管内皮生长因子(VEGF)药物治疗增殖性糖尿病视网膜病变(PDR)患者的效果观察。

方法：选择2018-07/2020-07本院收治的PDR患者作为研究对象,所有患者均行25G玻璃体切割术,术前7d给予抗VEGF药物,根据治疗方法分为雷珠单抗组(31例31眼)、康柏西普组(30例30眼)、阿柏西普组(29例29眼)。于玻璃体腔注射抗VEGF药物前及行玻璃体切割术时采集房水检测VEGF、色素上皮衍生因子(PEDF)水平,于术前及术后3、6mo时测定最佳矫正视力(BCVA)、黄斑中心凹视网膜厚度(CMT)。

结果：各组患者玻璃体腔注药后房水VEGF水平显著降低(P<0.05),PEDF水平升高(P<0.05),三组组间比较均无差异(P>0.05)。三组手术时间、术中出血、医源性裂孔发生情况比较均无差异(P>0.05)。三组患者术后3、6mo时BCVA显著优于术前(P<0.05),CMT显著低于术前(P<0.05),三组组间比较均无差异(P>0.05)。

结论：PDR患者玻璃体切割术前玻璃体腔注射抗VEGF药物可降低房水内血管相关因子的表达; 雷珠单抗、康柏西普、阿柏西普联合玻璃体切割术治疗PDR的临床疗效及安全性相当。