epidermal-growth-factor and Diabetic-Retinopathy

Diabetes mellitus is associated with typical patterns of long term vascular complications which vary with the organ involved. The microvascular kidney disease (Olgemoller and Schleicher, 1993) is characterized by thickening of the capillary basement membranes and increased deposition of extracellular matrix components (ECM), while loss of microvessels with subsequent neovascularisation is predominant in the eye and peripheral nerves. On the other hand macrovascular disease is characterized by accelerated atherosclerosis. These complications are dependent on long term hyperglycemia. Specific biochemical pathways linking hyperglycaemia to microvascular changes were proposed: the polyol pathway (Greene et al., 1987), non-enzymatic glycation of proteins (Brownlee et al., 1988), glucose autooxidation and oxidative stress (Hunt et al., 1990), hyperglycemic pseudohypoxia (Williamson et al., 1993) enhanced activation of protein kinase C by de novo-synthesis of diacyl glycerol (Lee et al., 1989; DeRubertis and Craven 1994) and others. These pathways are not mutually exclusive (Larkins and Dunlop, 1992; Pfeiffer and Schatz, 1992). They may be linked to alterations in the synthesis of growth factors particularly since atherosclerosis and angioneogenesis are associated with increased proliferation of endothelial and smooth muscle cells. Increased synthesis of ECM components is stimulated by growth factors like transforming growth factor beta (TGF beta) (Derynck et al., 1984) and insulin-like growth factor I (IGF-I) (Moran et al., 1991). This review will summarize some of the recent evidence for an involvement of growth factors in diabetic vascular complications and will attempt to assign their emergence in the sequence of events leading to vascular complications.

Topics: Animals; Arteriosclerosis; Diabetic Angiopathies; Diabetic Nephropathies; Diabetic Retinopathy; Epidermal Growth Factor; Fibroblast Growth Factor 2; Growth Hormone; Growth Substances; Humans; Hyperglycemia; Insulin Resistance; Insulin-Like Growth Factor I; Receptors, Somatotropin; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Topics: Adult; Aged; Aging; Alcoholism; Amino Acids; Anesthetics, Local; Animals; Anti-Infective Agents; Anti-Inflammatory Agents; Aqueous Humor; Autonomic Nervous System; Biological Transport, Active; Brain Chemistry; Cardiac Glycosides; Catecholamines; Cell Differentiation; Central Nervous System; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Epidermal Growth Factor; Eye; Fibrinolysis; Glaucoma; Granuloma; Graves Disease; Hallucinogens; Humans; Hypertension; Immunity, Cellular; Infant; Infant, Newborn; Leukotriene B4; Metabolism, Inborn Errors; Multiple Sclerosis; Muscle Relaxation; Nutritional Physiological Phenomena; Oxygen; Oxygen Consumption; Pigment Epithelium of Eye; Pineal Gland; Prostaglandin Antagonists; Prostaglandins; Psychotropic Drugs; Retina; Retinal Degeneration; Serotonin; Smoking; SRS-A; Stress, Physiological; Water-Electrolyte Balance

To determine differences in inflammatory markers expressed in diabetic macular edema (DME) patients with and without obstructive sleep apnea (OSA).. This was a prospective, cross-sectional study. Patients with treatment naive DME were enrolled in the study. They were stratified into 2 groups based on Apnea Hypopnea Index (AHI) from overnight polysomnography: OSA + (AHI ≥ 15) and OSA - (AHI<15). Multiplex immunoassay was performed for aqueous and serum cytokines including VEGF, placental growth factor (PGF), ICAM, IL2, IL3, IL6, IL8, IL10, IL17, vascular cell adhesion molecule-1 (VCAM1), monocyte attractant protein-1 (MCP1), epidermal growth factor (EGF) and platelet derived growth factor (PDGF). Statistical significance was defined as p < 0.004 using Bonferroni correction.. 32 DME positive patients were enrolled in the study; of which 17 patients were OSA + and 15 OSA-. The OSA + cohort had significantly higher levels of serum EGF (p = 0.003), and trended towards higher levels of most serum cytokines including ICAM and IL6. OSA- cohort had significantly higher levels of aqueous IL17 compared to the OSA + cohort (2.97 ± 1.7 vs. 1.4 ± 0.46 pg/mL, p = 0.004). There were no significant differences in other aqueous cytokines.. OSA + group trended towards higher levels of most serum inflammatory markers, suggesting a greater pro-inflammatory state. However, they did not have significantly greater level of aqueous cytokines.

Topics: Biomarkers; Cross-Sectional Studies; Cytokines; Diabetes Mellitus; Diabetic Retinopathy; Epidermal Growth Factor; Female; Humans; Inflammation Mediators; Interleukin-6; Macular Edema; Placenta Growth Factor; Prospective Studies; Sleep Apnea, Obstructive

This study evaluates diabetic macular-edema (DME) patients for the effect of intravitreal bevacizumab (IVB) \ injection on macular thickness and proangiogenic biomarkers in serum and vitreous.. Forty DME patients were analyzed for macular thickness (MT). Twelve proangiogenic biomarkers in serum \ and vitreous were analyzed before and after IVB.. Significant decrease in MT with vitreal vascular endothelial growth factor-A (VEGF-A) was observed as expected after IVB, \ while serum VEGF-A did not follow a decreasing trend in contrast to VEGF-C, which decreased both in serum and vitreous. Other \ vitreal factors like bone morphogenetic protein-9 (BMP9) and fibroblast growth factor (FGF) were also significantly decreased, while \ endothelial growth factor (EGF) increased following IVB. Before IVB, significant negative correlations were vitreous BMP9 with serum \ FGF, vitreous human growth factor (HGF) and interleukin-8 (IL-8) with serum endothelin, and vitreous and serum FGF and serum \ placental growth factor (PLGF) with EGF. After IVB, negative correlations in serum vs. vitreous were found for both HGF and PLGF \ with BMP9, and angiopoietin with FGF. Cube average thickness was negatively correlated with serum FGF and positively correlated \ with vitreous PLGF and endothelin.. Vascular endothelial growth factors are not the only factors that cause macular edema in diabetic patients. The effect of IVB \ on different proangiogenic biomarkers indicated a complex interplay of other factors in DME.

Topics: Adult; Aged; Angiogenesis Inhibitors; Angiopoietins; Bevacizumab; Biomarkers; Diabetic Retinopathy; Endothelins; Epidermal Growth Factor; Female; Fibroblast Growth Factors; Hepatocyte Growth Factor; Humans; Intercellular Signaling Peptides and Proteins; Interleukin-8; Intravitreal Injections; Macula Lutea; Macular Edema; Male; Middle Aged; Neovascularization, Pathologic; Placenta Growth Factor; Vascular Endothelial Growth Factor A; Vitreous Body

To compare the serum proangiogenic biomarkers in diabetic patients suffering from with and without diabetic retinopathy (DR).. An observational study.. Arif Memorial Teaching Hospital, Lahore, Pakistan and Institute of Molecular Biology and Biotechnology/Centre for Research in Molecular Medicine, The University of Lahore, Lahore, Pakistan, from March to December 2017.. Forty patients with DR were included in group A and 15 patients without retinopathy (controls) were included in group B. Twelve serum pro-angiogenic biomarkers [Angiopoietin 2, Human Growth Factor (HGF), Epidermal Growth Factor (EGF), Fibroblast Growth Factor (FGF), Placental Growth Factor (PLGF), Vascular Endothelial Growth Factor-A and C (VEGF-A and VEGF-C), Bone Morphogenetic Protein 9 (BMP9), Follistatin, Leptin, Interleukin-8 (IL8), Endothelin (ET)] were analysed by xMAP flow cytometry technique, results were compared between the two groups and statistical analysis was done using Mann-Whitney U test.. Serum ET, Follistatin and EGF were significantly raised in group A as compared to group B having p-values of 0.001, <0.001, and 0.033, respectively. Serum BMP9, Leptin, HGF, FGF and VEGF-C had p <0.001, 0.023, 0.020, and 0.009, respectively and were higher in group B than group A.. Serum ET, Follistatin and EGF were significantly higher in DR patients as compared to those without DR and should be considered to be significant biomarkers of retinal complications in diabetes mellitus.

Topics: Adult; Aged; Biomarkers; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Endothelins; Epidermal Growth Factor; Female; Flow Cytometry; Follistatin; Humans; Male; Middle Aged; Pakistan; Vascular Endothelial Growth Factor A

Diabetes mellitus is a disease with considerable morbidity and mortality worldwide. Breakdown of the blood-retinal barrier and leakage from the retinal vasculature leads to diabetic macular edema, an important cause of vision loss in patients with diabetes. Although epidemiologic studies and randomized clinical trials suggest that glycemic control plays a major role in the development of vascular complications of diabetes, insulin therapies for control of glucose metabolism cannot prevent long-term retinal complications. The phenomenon of temporary paradoxical worsening of diabetic macular edema after insulin treatment has been observed in a number of studies. In prospective studies on non-insulin-dependent (type 2) diabetes mellitus patients, a change in treatment from oral drugs to insulin was often associated with a significant increased risk of retinopathy progression and visual impairment. Although insulin therapies are critical for regulation of the metabolic disease, their role in the retina is controversial. In this study with diabetic mice, insulin treatment resulted in increased vascular leakage apparently mediated by betacellulin and signaling via the epidermal growth factor (EGF) receptor. In addition, treatment with EGF receptor inhibitors reduced retinal vascular leakage in diabetic mice on insulin. These findings provide unique insight into the role of insulin signaling in mediating retinal effects in diabetes and open new avenues for therapeutics to treat the retinal complications of diabetes mellitus.

Topics: ADAM Proteins; ADAM10 Protein; Amyloid Precursor Protein Secretases; Animals; Betacellulin; Blood Vessels; Capillary Permeability; Diabetic Retinopathy; Endothelial Cells; Epidermal Growth Factor; ErbB Receptors; Female; Humans; Insulin; Intercellular Signaling Peptides and Proteins; Macular Edema; Membrane Proteins; Mice; Mice, Inbred C57BL; Protective Agents; Protein Kinase Inhibitors; Retina; Retinal Pigment Epithelium; Signal Transduction; Tight Junctions

Many growth factors are implicated in proliferative diabetic retinopathy (PDR). It was decided to test the hypothesis that no one factor is predominant but that a regular profile of levels of different growth factors might be operating, and that the profile might differ according to whether or not insulin therapy was part of the patient's glycaemic management. The levels of several growth factors in vitrectomy samples were therefore determined from diabetic patients with tractional, non-haemorrhagic sequelae of PDR and these levels were correlated with (a) each other (growth factor profile), (b) neovascular activity, and (c) the method of glycaemic management (insulin treated (IT) or non-insulin treated (NIT)).. 72 samples of vitreous were obtained from either diabetic patients with PDR (n = 51) or non-diabetic (control) patients (n = 21). Levels of bFGF, IGF-I, EGF, and insulin were determined by radioimmunoassay; levels of TGF-beta 2 by ELISA; and levels of IGF-I binding protein by western ligand blotting. The data were analysed using appropriate statistics.. There was no regular growth factor profile. bFGF levels were significantly greater in vitreous from NIT patients compared with IT patients and controls. The highest levels of bFGF were found in NIT patients with actively vascularised membranes. TGF-beta 2 levels were significantly greater in vitreous from IT patients compared with NIT patients and controls The highest levels of TGF-beta 2 were found in IT patients with actively vascularised membranes. IGF-I levels were significantly greater in diabetics (irrespective of insulin treatment) than non-diabetics and the highest levels of IGF-I were found in IT patients with actively vascularised membranes. A 34 kDa IGFBP was the predominant IGFBP identified in vitreous and was found to be elevated in diabetics patients.. In PDR there is a correlation between intravitreal growth factor levels and both disease state (whether active or fibrotic) and method of glycaemic management.

Topics: Analysis of Variance; Case-Control Studies; Diabetic Retinopathy; Enzyme-Linked Immunosorbent Assay; Epidermal Growth Factor; Fibroblast Growth Factor 2; Growth Substances; Humans; Hypoglycemia; Insulin; Insulin-Like Growth Factor Binding Proteins; Insulin-Like Growth Factor II; Middle Aged; Neovascularization, Pathologic; Radioimmunoassay; Transforming Growth Factor beta; Vitreous Body

A number of growth factors have been implicated in the development and perpetuation of preretinal fibrovascular membranes in patients with proliferative diabetic retinopathy (PDR). The aim of this study was to determine the potential role of epidermal growth factor (EGF), transforming growth factor alpha (TGF-alpha), and their receptor (EGF-R) in PDR development. Immunostaining for EGF, TGF-alpha, and EGF-R was compared between normal retina, PDR retina, and PDR preretinal membranes. Weak staining for EGF and EGF-R was observed throughout the neural retina from non-diabetic eyes while weak to moderate staining for TGF-alpha was observed in the ganglion cell layer and the inner and outer nuclear layers. In contrast, intense staining for EGF and TGF-alpha and moderate staining for EGF-R were observed throughout the PDR retina. Immunoreactivity for EGF, TGF-alpha, and EGF-R was seen in the majority of the 11 excised membranes studied and, though variable, was generally greater than that observed in normal retinas. These results suggest an autocrine/paracrine role for EGF, TGF-alpha, and EGF-R in PDR.

Topics: Diabetic Retinopathy; Endothelium, Vascular; Epidermal Growth Factor; ErbB Receptors; Humans; Immunohistochemistry; Retina; Transforming Growth Factor alpha

Protein synthesis and deposition by vascular endothelial cells play an important role in the neovascularization seen in diabetic retinopathy. In the present study, we have compared the pattern of protein accumulation in human retinal endothelial cells derived from diabetic and nondiabetic individuals. Confluent cultures of retinal endothelial cells were incubated for 18 h with a mixture of radiolabeled methionine and cysteine. Under basal conditions, without the addition of growth factors, diabetic retinal endothelial cells accumulated less radiolabeled protein than did cells of nondiabetic origin. Both epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) enhanced protein accumulation in cells of diabetic origin, but not in cells of nondiabetic origin. Analysis of radiolabeled proteins in the secreted fraction by sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) revealed prominent protein bands at 220 and 49.5 kD in both diabetic and nondiabetic cultures that were identified by immunoblot analysis as fibronectin and a mixture of secreted protein acidic and rich in cysteine (SPARC) and plasminogen activator inhibitor-1 (PAI-1), respectively. The levels of PAI-1 were higher in the secreted fractions of diabetic cultures than in nondiabetic cultures. SDS-PAGE and autoradiography of the secreted fraction also revealed two protein components of approximate molecular weight 440 and 78 kD, which were present in fractions of diabetic origin but absent in those of nondiabetic origin. Our studies support unique differences in protein expression in cells of diabetic vs. nondiabetic origin in response to EGF and bFGF and identify two proteins exclusively expressed by cells of diabetic origin.

Topics: Adult; Cells, Cultured; Cysteine; Diabetic Retinopathy; Electrophoresis, Polyacrylamide Gel; Endothelium, Vascular; Epidermal Growth Factor; Eye Proteins; Female; Fibroblast Growth Factors; Humans; Immunoblotting; Male; Methionine; Middle Aged; Molecular Weight; Retina

The authors examined the effect of insulin-like growth factor 1 (IGF 1), epidermal growth factor (EGF), and acidic fibroblast growth factor (AFGF) on the synthesis by human retinal endothelial cell (HREC) of plasminogen activators (PA; tissue-type [t-PA] and urokinase-type [u-PA]) and plasminogen activator inhibitor (PAI). Immunologic and functional assays for t-PA, u-PA, and PA1 were conducted with cell lines derived from three diabetics and three nondiabetic controls. Confluent HREC of nondiabetic origin did not respond to IGF I (100 ng/ml) with any change of t-PA antigen in the medium (10.7 +/- 1.1 ng/ml unstimulated versus 10.1 +/- 0.8 ng/ml) stimulated, P = not significant). Likewise AFGF and EGF caused no significant change of t-PA levels. Both IGF I and EGF caused a significant increase of t-PA from HREC of diabetic origin (9.6 +/- 0.8 ng/ml unstimulated versus 16.6 +/- 1.9 ng/ml IGF I-stimulated, P less than 0.001, and 14.6 +/- 2.7 ng/ml EGF-stimulated P less than 0.005). Supplementation of AFGF had no effect on HREC of diabetic origin. In confluent cultures, only small quantities of u-PA were detected. After wounding confluent cultures, u-PA activity was associated with cells migrating from the wound edges. Functional PA activity was also measured by chromogenic assay. Results further supported a predominance of t-PA activity being produced by confluent HREC in culture. These results suggest that modulation of PA production by HREC is influenced by exposure to growth factors, by the state of confluency, and the origin of the cells (diabetic vesus nondiabetic).

Topics: Aged; Cell Movement; Cells, Cultured; Diabetic Retinopathy; Endothelium; Epidermal Growth Factor; Fibroblast Growth Factor 1; Humans; Immunoenzyme Techniques; Insulin-Like Growth Factor I; Middle Aged; Plasminogen Activators; Plasminogen Inactivators; Retina; Tissue Plasminogen Activator; Wound Healing

The development and extension of fibrovascular or fibroglial membranes onto the retinal surface are a major cause of visual loss in diabetic patients with proliferative retinopathy and in patients suffering from retinal detachment with proliferative vitreoretinopathy. The pathogenesis of these proliferative diseases, however, remain poorly understood and the nature of growth-promoting mediators implicated in these phenomena has not been determined yet. Using indirect immunofluorescence procedures, three different growth factors known to be mitogenic for various cell components of preretinal membranes, acidic fibroblast growth factor, epidermal growth factor and insulin-like growth factor type I, were sought in 14 specimens of preretinal proliferative tissues. Similar results were obtained in diabetic preretinal membranes and tissues from patients with proliferative vitreoretinopathy. The three different growth factors were found diffusely in the connective stroma and around new blood vessels within the vascular walls. Some fibroblast-like and pigment epithelial-derived cells more markedly reacted with anti-growth factor antibodies. These results provide indications on the eventual involvement of three potent growth factors in intraocular proliferative diseases, but whether or not these mediators play an active role in the development of preretinal membranes remains to be determined.

Topics: Adult; Aged; Antibodies, Monoclonal; Cell Membrane; Diabetic Retinopathy; Epidermal Growth Factor; Eye Diseases; Fibroblast Growth Factor 1; Fluorescent Antibody Technique; Growth Substances; Humans; Insulin-Like Growth Factor I; Middle Aged; Retinal Diseases; Vitreous Body