Diabetic retinopathy is a serious complication of diabetes and is the leading cause of blindness in people with diabetes. At present, there are many views on the pathogenesis of diabetic retinopathy, including the changes of retinal microenvironment caused by high glucose, the formation of advanced glycation end products, oxidative stress injury, inflammatory reaction and angiogenesis factor. These mechanisms produce a common pathway that leads to retinal degeneration and microvascular injury in the retina. In recent years, cell regeneration therapy plays an increasingly important role in the process of repairing diseases. Different types of stem cells have neurological and vascular protection for the retina, but the focus of the target is different. It has been reported that stem cells can regulate the retinal microenvironment and protect the retinal nerve cells by paracrine production, and can also reduce immune damage through potential immunoregulation, and can also differentiate into damaged cells by regenerative function. Combined with the above characteristics, stem cells show the potential for the repair of diabetic retinopathy, this stem cell-based regenerative therapy for clinical application provides a pre-based evident. However, in the process of stem cell transplantation, homogeneity of stem cells, cell delivery, effective homing and transplantation to damaged tissue is still a problem of cell therapy.
Purpose Researching the relared risk factors of diabetic retinopathy (DR) through the epidemiological investigation. Methods Basing on a population random sampling survey and screening in 6 areas and cities of Anhui,216 diabetics were screened and they were then investigated in detail by filling in forms,measuring blood pressure,ocular examination including ophthalmoscopy,and lab examination including fasting blood glucose (FBG),blood glucose 2 hours after meal,urine albumin excretion (UAE),serum triglyceride,and cholesterol. Results The resultant date revealed that the duration of diabetes,blood pressure FBG and UAE were associated significantly with DR (Plt;0.05),and serum triglyceride and cholesterol were associated not significantly with DR(Pgt;0.05). Conclusion Long duration of diabetes,hight FBG and hight blood pressure are the important risk factors of DR,and urine albumin might forebode the occurrence of DR. (中华眼底病杂志,1998,14:119-121)
Objective To observe the genetic predisposition of complement C5 gene polymorphisms in proliferative diabetic retinopathy (PDR) in Chongqing Han population. Methods 400 type 2 diabetes (T2D) patients (case group) and 600 age- and sex-matched healthy controls (control group) were enrolled in this study. There were 8 PDR patients in case group. All the subjects were Han ethnic people. The immune-related representative SNP locus of C5 gene including rs2269067, rs7040033, rs7027797 were screened by linkage disequilibrium analysis. Locus rs1017119 was selected by TagSNP and was around the above three loci. Subjects′ peripheral venous blood was collected and DNA was extracted. Genotyping was examined by PCR-restriction fragment length polymorphism method. The level of C5 plasma protein was measured by enzyme-linked immunoabsorbent assay. Results The frequency of GG genotype of rs2269067 was significantly increased in PDR patients in cases group compared with controls (Pc=3.4×10-5, OR=1.87, 95%CI=1.43 - 2.44；P=3.1×10-6). There was no differences in frequency of G, CC and CG genotype of rs2269067 between two groups (P=1.4×10-4, 1.000, 1.0×10-6). There were no differences in frequency of G, CC, CG, GG genotype of rs7040033, rs1017119, and rs7027797 between two groups (P > 0.05). The production of C5 plasma protein was significantly increased in case group as compare with control group (P=0.0004). An increased production of C5 plasma protein was observed in rs2269067 GG genotype cases compared to CG or CC cases (P=0.003, 0.001). Conclusion C5 rs2269067 GG genotype may be associated with the PDR of T2D in Chongqing Han population.
Objective To observe the correlation between postmenopausal estrogen levels and diabetic retinopathy (DR) in women. Methods Thirty-nine menopause female patients with type 2 diabetes mellitus and 17 menopause subjects (control group) were enrolled in this study. Control subjects aged from 53 to 82 years, with the mean age of (69.80±8.32) years. Diabetes mellitus patients aged from 56 to 84 years, with the mean age of (70.50±8.27) years; diabetes duration ranged from 3 to 23 years, with the average course of diabetes (11.40±7.97) years. DR diagnosis was according to the results of fundus fluorescein angiography, and thus the 39 patients were divided into DR group (19 patients) and non-DR (NDR) group (20 patients). There was no significant difference in age and menopause duration between the three groups (t=0.347, 0.485;P＞0.05). There was significant difference in diabetes course (t=2.748,P＜0.05). Compared with NDR group, fasting blood glucose (FBG), glycosylated hemoglobin (HbA1c), total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C) were significantly increased (t=6.130, 5.322, 4.574, 2.426, 4.033), high density lipoprotein cholesterol (HDL-C) was significantly lower (t=3.917), the difference was statistically significant (P＜0.05). The level of estradiol (E2) was measured by radioimmunoassay. The differences of E2 levels between the three groups were compared. Logistic regression analysis was used to analyze the influencing factors of DR. Results The levels of E2 in control group, DR group and NDR group were (42.38±8.64), (21.49±9.81) and (32.72±10.51) pg/ml, respectively. The level of E2 in DR group was significantly lower than that in NDR group and control group (t=3.443, 10.110;P＜0.05). Logistic regression analysis showed that the duration of diabetes mellitus [coefficients =0.166, odds ratio (OR)=1.181,P= 0.016], FBG (coefficients=1.162,OR=4.014,P=0.001), TC (coefficients=3.212,OR=10.820,P=0.002), TG (coefficients=1.649,OR=5.203,P= 0.030) and LDL-C (coefficients=1.605,OR= 4.976,P=0.003) were the risk factors for DR; E2 (coefficients=−0.100,OR=0.904,P=0.004) and HDL-C (coefficients=−4.460,OR=0.012,P=0.002) were the protective factors for DR. Conclusion The estrogen level of postmenopausal women have a certain correlation with the development of DR, it may be one of the protective factor of DR.
ObjectiveTo assess the association of vascular endothelial growth factor (VEGF) gene-460C/T and-634C/G polymorphism with diabetic retinopathy (DR) among patients in Asia and European by meta-analysis. MethodsA systematic search of electronic databases (PubMed, Cochrane Library, EMBASE, VIP, Wanfang technological, CNKI, etc.) was carried out until Jun, 2014. Case-control studies on the relationship between genetic polymorphism of VEGF-460C/T and VEGF-634C/G with diabetic retinopathy were included in this analysis. The data were quantitatively analyzed by RevMan 5.0 software after assessing the quality of included studies. The pooled odds ratios (OR) and their corresponding 95% confidence intervals (CI) were used to assess the strength of the association. ResultsVEGF-460C/T (7 studies:899 cases and 786 controls) and VEGF-634C/G (10 studies:1615 cases and 1861 controls) were inclued in this meta-analysis. Significant association was found for-460C/T polymorphism in Aisa (C versus T:OR=1.52, 95%CI was, Z=3.72, P=0.0002; CC versus CT+TT:OR=1.61, 95%CI was[1.22, 1.90], Z=3.05, P=0.002; TT versus CT+CC:OR=0.64, 95%CI was[1.19, 2.19], Z=2.07, P=0.04), and VEGF-634CC gene type was associated with DR in European (OR=1.56, 95%CI[1.08, 2.25], Z=2.37, P=0.02). No significant publication bias was found. ConclusionsThe meta-analysis demonstrated that DR was associated with VEGF-460C/T polymorphism in Asia, and C alleles and CC gene type was the risk polymorphism; VEGF-634C/G polymorphism was not associated with DR, but its CC genotype maybe the risk factor in European. Further case-control studies based on larger sample size are still needed, especially for-634C/G polymorphism.
ObjectiveTo observe RNA-Seq analysis of gene expression profiling in retinal vascular endothelial cells after anti-vascular endothecial growth factor (VEGF) treatment.MethodsRetinal vascular endothelial cells were cultured in vitro, and the logarithmic growth phase cells were used for experiments. The cells were divided into the control group and high glucose group. The cells of two groups were cultured for 5 hours with 5, 25 mmol/L glucose, respectively. And then, whole transcriptome sequencing approach was applied to the above two groups of cells through RNA-Seq. Now with biological big data obtained as a basis, to analyze the differentially expressed genes (DEGs). And through enrichment analysis to explain the differential functions of DEGs and their signal pathways.ResultsThe gene expression profiles of the two groups of cells were obtained. Through analysis, 449 DEGs were found, including 297 upregulated and 152 downregulated ones. The functions of DEGs were influenced by regulations over molecular biological process, cellular energy metabolism and protein synthesis, etc. Among these genes, ITGB1BP2, NCF1 and UNC5C were related to production of inflammation; AKR1C4, ATP1A3, CHST5, LCTL were related to energy metabolism of cells; DAB1 and PRSS55 were related to protein synthesis; SMAD9 and BMP4 were related to the metabolism of extracellular matrix. GO enrichment analysis showed that DEGs mainly act in three ways: regulating biological behavior, organizing cellular component and performing molecular function, which were mainly concentrated in the system generation of biological process part and regulation of multicellular organisms. Pathway enrichment analysis showed that gene expressions of the two cell groups were differentiated in transforming growth factor-β (TGF-β) signaling pathway, complement pathway and amino acid metabolism-related pathways have also been affected, such as tryptophan, serine and cyanide. Among them, leukocyte inhibitory factor 9 and bone morphogenetic protein 4 play a role through the TGF-β signaling pathway.ConclusionsHigh glucose affects the function of retinal vascular endothelial cells by destroying transmembrane conduction of retinal vascular endothelial cells, metabolism of extracellular matrix, and transcription and translation of proteins.
Microvesicles (MVs) is small membrane vesicles released from different cell types under different conditions. Studies have shown that MVs may mediate vascular inflammation, angiogenesis, and other pathological processes. MVs may play an important role in the pathogenesis of diabetic retinopathy (DR) by mediating endothelial cell injury, thrombosis and neovascularization. The plasma MV level may be an effective parameter to monitor the development of DR. This article will summarize the research progress of the relationship between MVs and DR in recent years.
ObjectiveTo observe the changes in open probability and protein expression of large conductance Ca2+-activated K+ (BK) channel in retinal vascular smooth muscle cells (RVSMCs) of diabetic rats. MethodsStreptozotocin (STZ)-induced rat diabetic animal model was established by STZ injection intraperitoneally.RVSMCs were isolated by enzyme digestion. The BK currents in control and diabetic groups were recorded by patch clamp technique in single channel configuration. BK channel protein expression in control and diabetic group were measured by Western blot. ResultsCompared with control group, the NP0 of BK channels in diabetic group were significantly increased (t=4.260, P < 0.05). Compared with control group, there was no significant difference inα-subunit protein expression in diabetic group in RVSMCs (t=10.126, P > 0.05); however, β1-subunit protein expression was remarkably increased in diabetic group (t=5.146, P < 0.05). ConclusionThe NP0 of BK channels andβ1-subunit protein expression are increased in RVSMCs of diabetic rats.
Dyslipidemia plays an important role in the pathogenesis of diabetic retinopathy (DR).Apreliminary study found that low-density lipoprotein cholesterol, apolipoprotein (Apo)Band ApoB/ Apo A1 ratio were positively correlated with DR, while high-density lipoprotein cholesterol, Apo A1 was negatively correlated with DR and proliferative DR. Reducing the blood fats to be helpful to DR control. However, the mechanism of hyperlipidemia in the pathogenesis of DR, the reason of dyslipidemia in diabetic patients and the interaction between hyperglycemia and hyperlipidemia in DR are not clear yet. Moreover, there is no predictive indicators related to blood lipid for DR. Understanding the relationship between dyslipidemia and DR can provide definite evidence for fat-reducing therapy for DR control.
Objective To investigate the relationship between subclinical hypothyroidism (SCH) and diabetic retinopathy (DR) in patients with type 2 diabetes mellitus (T2DM). Methods A total of 792 patients of T2DM were enrolled in the study. There were 448 males and 344 females, with an average age of (54.13±13.06) years. The average duration of diabetes was (8.03±6.70) years. The patients were grouped according to the degree of DR and thyroid function. Among them, 483 patients (61.0%) were no DR, 240 patients (30.3%) were mild DR, 69 patients (8.7%) were severe DR. 725 patients (91.5%) were normal thyroid function, 67 patients (8.5%) were SCH. The prevalence of SCH among no DR group, mild DR group and severe DR group was compared. And the prevalence of DR between normal thyroid function group and SCH group was compared. Logistic regression analysis was used to estimate the association between SCH and DR. Results No significant differences among the three groups (no DR group, mild DR group, severe DR group) were found in the prevalence of SCH (χ2=1.823,P=0.402). There were no significant differences in the incidences of DR between normal thyroid function group and SCH group (χ2=1.618,P=0.239). Logistic regression analysis demonstrated that SCH was not significant associated with DR [mild DR: odds ratio (OR)=1.361, 95% confidence interval (CI)=0.773−2.399,P=0.286; severe DR:OR=1.326, 95%CI=0.520−3.384,P=0.555; DR:OR=1.353, 95%CI=0.798−2.294,P=0.261). Conclusion SCH is not significant associated with DR in patients with T2DM.