We performed a retrospective study of serum factors associated with neovascular glaucoma that can occur following vitrectomy for proliferative diabetic retinopathy. The medical records of 183 patients (241 eyes) who received vitrectomy between August 1996 and August 2000 were studied retrospectively and subsequently analyzed by linear logistic regression analysis and multiple logistic regression tests. Neovascular glaucoma developed at an average of 2.7 months in 31 of 241 eyes (14.1%). The overall anatomical success rate of retinal attachment was 82.5% (199 eyes in 241 eyes), although it decreased to 45.1% (14 eyes in 31 eyes) in eyes with neovascular glaucoma. Serum cholesterol (P = 0.041) and fibrinogen levels (P = 0.020) were significantly associated with the development of neovascular glaucoma. However, no significant association could be found concerning hypertension, diabetic retinopathy or hypercholesterolemia (P > 0.05). We suggest that serum creatinine, cholesterol and fibrinogen levels can be used to predict the development of neovascular glaucoma in vitrectomized eyes with diabetic retinopathy and can further provide a more active approach to preventing the development of this condition.
Adult ; Aged ; Aged, 80 and over ; Blood/metabolism ; Cell Division ; Diabetic Retinopathy/*pathology/*surgery ; Glaucoma, Neovascular/*blood/*complications ; Human ; Middle Age ; Postoperative Period ; Retrospective Studies ; *Vitrectomy

PURPOSE: To compare the levels of calcium and phosphorus in the aqueous humor and serum of diabetics and non-diabetics. METHODS: We divided patients into two groups: seventy-six non-diabetic cataract patients and fifty-two diabetic cataract patients. The diabetic group was divided again into three subgroups: twenty-six patients with no diabetic retinopathy, thirteen patients with non-proliferative diabetic retinopathy, and thirteen patients with proliferative diabetic retinopathy. The authors compared the levels of calcium and phosphorus in the serum and aqueous humor of cataract patients. Statistic analysis was performed to form two comparisons: 1) a comparison between non-diabetics and diabetics and 2) a comparison among non-diabetics and the three subgroups of diabetics. RESULTS: In serum, calcium levels did not statistically differ between non-diabetics and diabetics. The phosphorus level was also not significantly different. In the aqueous humor, however, while calcium levels did not differ significantly, the phosphorus levels in diabetics were considerably higher than those in non-diabetics. When non-diabetics were compared to the three diabetic subgroups, calcium levels did not differ in serum or aqueous humor, but the phosphorus levels in diabetics with proliferative diabetic retinopathy were significantly higher than those in non-diabetics, diabetics without diabetic retinopathy, and diabetics with non-proliferative diabetic retinopathy. CONCLUSIONS: The level of phosphorus in the aqueous humor and serum of diabetics was significantly increased, especially in diabetics with proliferative diabetic retinopathy. This result may be related to hydrophilic acrylic IOL opacification. Future studies regarding the pathogenic role of a high concentration of aqueous humor and serum phosphorus are required.
Aged ; Aged, 80 and over ; Aqueous Humor/*chemistry ; Biological Markers/analysis ; Calcium/*analysis ; Cataract/complications/*metabolism ; Diabetic Retinopathy/complications/*metabolism ; Female ; Humans ; Male ; Middle Aged ; Phosphorus/*analysis ; Regression Analysis ; Retrospective Studies

PURPOSE: To compare the levels of calcium and phosphorus in the aqueous humor and serum of diabetics and non-diabetics. METHODS: We divided patients into two groups: seventy-six non-diabetic cataract patients and fifty-two diabetic cataract patients. The diabetic group was divided again into three subgroups: twenty-six patients with no diabetic retinopathy, thirteen patients with non-proliferative diabetic retinopathy, and thirteen patients with proliferative diabetic retinopathy. The authors compared the levels of calcium and phosphorus in the serum and aqueous humor of cataract patients. Statistic analysis was performed to form two comparisons: 1) a comparison between non-diabetics and diabetics and 2) a comparison among non-diabetics and the three subgroups of diabetics. RESULTS: In serum, calcium levels did not statistically differ between non-diabetics and diabetics. The phosphorus level was also not significantly different. In the aqueous humor, however, while calcium levels did not differ significantly, the phosphorus levels in diabetics were considerably higher than those in non-diabetics. When non-diabetics were compared to the three diabetic subgroups, calcium levels did not differ in serum or aqueous humor, but the phosphorus levels in diabetics with proliferative diabetic retinopathy were significantly higher than those in non-diabetics, diabetics without diabetic retinopathy, and diabetics with non-proliferative diabetic retinopathy. CONCLUSIONS: The level of phosphorus in the aqueous humor and serum of diabetics was significantly increased, especially in diabetics with proliferative diabetic retinopathy. This result may be related to hydrophilic acrylic IOL opacification. Future studies regarding the pathogenic role of a high concentration of aqueous humor and serum phosphorus are required.
Aged ; Aged, 80 and over ; Aqueous Humor/*chemistry ; Biological Markers/analysis ; Calcium/*analysis ; Cataract/complications/*metabolism ; Diabetic Retinopathy/complications/*metabolism ; Female ; Humans ; Male ; Middle Aged ; Phosphorus/*analysis ; Regression Analysis ; Retrospective Studies

PURPOSE: The purpose of this study was to evaluate whether any stage of diabetic retinopathy (DR) is associated with levels of plasma erythropoietin and other plasma parameters. METHODS: It was examined a representative sample of 180 type 2 diabetes patients aged 40 to 79 years. Ophthalmic examination including a funduscopic examination, performed by an experienced ophthalmologist and the retinal finding were classified according to the grading system for diabetic retinopathy of ETDRS (Early Treatment Diabetic Retinopathy Study). It was measured the levels of plasma erythropoietin, cholesterol, triglyceride, apolipoproteins A and B, C-reactive protein, fasting blood glucose and hemoglobin A1C (HbA1C) in 88 DR patients and 92 controls without DR. Risk factors correlated with DR were compared between groups. RESULTS: The study group of 180 patients included 72 males and 108 females. The mean age of the patients with and without DR was 57.36 ± 8.87 years and 55.33 ± 8.28 years, respectively. Of the 88 patients with DR, only 9 (10%) had proliferative DR and the rest suffered from non-proliferative DR. The mean plasma levels of erythropoietin in proliferative DR group showed a significant difference in comparison to other groups. The mean plasma levels of cholesterol, triglyceride, apolipoproteins A and B, C-reactive protein, and fasting blood glucose were not significantly different in the three groups except for HbA1C. The absolute relative risk (ARR) also showed that erythropoietin was an increasing risk for proliferative DR (ARR, 1.17; 95% confidence interval, 1.060 to 1.420; odds ratio,1.060). CONCLUSIONS: Of the factors studied, erythropoietin level showed significant increase in proliferative DR group. The stepwise raised in mean plasma erythropoietin level which demonstrates significant correlation with proliferative DR versus remaining two groups, will be an indication of its role in proliferative DR.
Adult ; Aged ; Blood Glucose/metabolism ; Cholesterol/blood ; Cross-Sectional Studies ; Diabetes Mellitus, Type 2/complications ; Diabetic Retinopathy/*blood/diagnosis/*epidemiology ; Enzyme-Linked Immunosorbent Assay ; Erythropoietin/*blood ; Female ; Fluorescein Angiography ; Hemoglobin A, Glycosylated/metabolism ; Humans ; Male ; Middle Aged ; Risk Factors

To evaluate the effect of chlorogenic acid (CGA), a polyphenol abundant in coffee, on retinal vascular leakage in the rat model of diabetic retinopathy, Sprague-Dawley rats were divided into four groups: controls, streptozotocin-induced diabetic rats, and diabetic rats treated with 10 and 20 mg/kg chlorogenic acid intraperitoneally daily for 14 days, respectively. Blood-retinal barrier (BRB) breakdown was evaluated using FITC-dextran. Vascular endothelial growth factor (VEGF) distribution and expression level was evaluated with immunohistochemistry and Western blot analysis. Expression of tight junction proteins, occludin and claudin-5, and zonula occludens protein, ZO-1 was also evaluated with immunohistochemistry and Western blot analysis. BRB breakdown and increased vascular leakage was found in diabetic rats, with increased VEGF expression and down-regulation of occludin, claudin-5, and ZO-1. CGA treatment effectively preserved the expression of occludin, and decreased VEGF levels, leading to less BRB breakdown and less vascular leakage. CGA may have a preventive role in BRB breakdown in diabetic retinopathy by preserving tight junction protein levels and low VEGF levels.
Animals ; Blood-Retinal Barrier/*drug effects ; Chlorogenic Acid/metabolism/*pharmacology ; Claudin-5/metabolism ; Dextrans/chemistry ; Diabetes Mellitus, Experimental/complications/metabolism/*pathology ; Diabetic Retinopathy/etiology/prevention & control ; Down-Regulation ; Fluorescein-5-isothiocyanate/chemistry ; Male ; Occludin/metabolism ; Rats ; Rats, Sprague-Dawley ; Retina/*metabolism ; Tight Junction Proteins/metabolism ; Vascular Endothelial Growth Factor A/metabolism ; Zonula Occludens-1 Protein/metabolism

BACKGROUNDDiabetic retinopathy (DR) is a leading cause of visual impairment and blindness among the people of occupational age. To prevent the progress of retina injury, effective therapies directed toward the key molecular target are required. Grape seed proanthocyanidin extracts (GSPE) have been reported to be effective in treating diabetic complications, while little is discussed about the functional protein changes.

METHODSWe used streptozotocin (STZ) to induce diabetes in rats. GSPE (250 mg/kg body weight per day) were administrated to diabetic rats for 24 weeks. Serum glucose, glycated hemoglobin and advanced glycation end products (AGEs) were determined. Consequently, 2-D difference gel electrophoresis and mass spectrometry were used to investigate retina protein profiles among control, STZ-induced diabetic rats, and GSPE treated diabetic rats.

RESULTSGSPE significantly reduced the AGEs of diabetic rats (P < 0.05). Moreover, GSPE significantly suppressed the vascular lesions of central regions, decreased capillary enlargements and neovascularization, similar to those of the control rats under light microscope. Eighteen proteins were found either up-regulated or down-regulated in the retina of STZ-induced diabetic rats. And seven proteins in the retina of diabetic rats were found to be back-regulated to normal levels after GSPE therapy. These back-regulated proteins are involved in many important biological processes such as heat shock, ubiquitin-proteasome system, cell proliferation, cell growth and glucose metabolism.

CONCLUSIONSThese findings might promote a better understanding for the mechanism of DR, and provide novel targets for evaluating the effects of GSPE therapy.

Animals ; Blood Glucose ; drug effects ; metabolism ; Body Weight ; drug effects ; Diabetes Mellitus, Experimental ; complications ; metabolism ; pathology ; Diabetic Retinopathy ; drug therapy ; metabolism ; pathology ; Electrophoresis, Gel, Two-Dimensional ; Glycated Hemoglobin A ; metabolism ; Glycation End Products, Advanced ; metabolism ; Grape Seed Extract ; Male ; Plant Extracts ; pharmacology ; Proanthocyanidins ; pharmacology ; Proteomics ; methods ; Rats ; Rats, Wistar

OBJECTIVETo evaluate the role of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and plasma homocysteine levels in Chinese patients with type 2 diabetes mellitus and diabetic retinopathy (DR).

METHODSMTHFR genetic C677T polymorphisms were determined by PCR-restriction fragment length polymorphism. Total plasma homocysteine levels were measured using high-performance liquid chromatography (HPLC) with fluorescence detection.

RESULTSThe frequencies of MTHFR T homogenetic type and CT heterogenetic type and allele T (28.18%, 41.82%, 49.09%) in type 2 diabetic patients with diabetic retinopathy were significantly higher than those in diabetic patients without retinopathy (18.37%,29.59%,33.16%) or the normal controls (17.54%, 28.07%, 31.58%). Howerver, there were no significant differences in the frequency of MTHFR genotype and allele between the type 2 diabetic patients without retinopathy and the normal controls. The presence of T allele appeared to have a strong association with the development of diabetic retinopathy. The odds ratio was 1.94 and the 95% confidence interval was 1.31-2.88. Moreover, the plasma homocysteine levels in patients with TT or CT genotype were markedly higher than those in patients with CC genotype.

CONCLUSIONMTHFR gene C677T mutation associated with a predisposition to increase of plasma homocysteine may represent a genetic risk factor for diabetic retinopathy in Chinese type 2 diabetes mellitus.

Adult ; Alleles ; DNA ; genetics ; metabolism ; Deoxyribonucleases, Type II Site-Specific ; metabolism ; Diabetes Mellitus, Type 2 ; blood ; complications ; genetics ; Diabetic Retinopathy ; blood ; etiology ; genetics ; Female ; Gene Frequency ; Genotype ; Homocysteine ; blood ; Humans ; Male ; Methylenetetrahydrofolate Reductase (NADPH2) ; Middle Aged ; Oxidoreductases Acting on CH-NH Group Donors ; genetics ; Point Mutation ; Polymorphism, Genetic