Epigenetic modifications such as DNA methylation, histone post-translational modifications, non-coding RNA are reversible, heritable alterations which are induced by environmental stimuli. Major risk factors of diabetes and diabetic complications including hyperglycemia, oxidative stress and advanced glycation end products, can lead to abnormal epigenetic modifications in retinal vascular endothelial cells and retinal pigment epithelium cells. Epigenetic mechanisms are involved in the pathogenesis of macular edema and neovascularization of diabetic retinopathy (DR), as well as diabetic metabolic memory. The heritable nature of epigenetic marks also playsakey role in familial diabetes mellitus. Further elucidation of epigenetic mechanisms in DR can open the way for the discovery of novel therapeutic targets to prevent DR progression.
To evaluate the tberapeutlc effect of diode laser photocoagulation trearment on eases of diabetic retinopathy with certain degree of refractive media opacity. METHODS: Diode laser photocoagulation treatment were given to 36 selected cases (40 eyes )of diabetic retinopathy who can not be treated with argon laser because of refractive media opacity, Before and after treatment,visual acuity and fundus were examined and fundus fluorescein angiography and retinal color photographp were taken. The follow-up period was 8~14 months (with an average of 11 months) RESULT:Visual acuity were improved or maintained in 29 eyes(about 73%)of the 34 eyes of proliferative diabetic retinopathy ,retinal new vessels partly or entirely regressed in 25 eyes(about 74%). CONCLUTION ;Tbe effect of diode laser treatment on patients with diabetic retinopatby with certain degree of lens/vitreous opacity is relatively safisfactory. （Chin J Ocul Fundus Dis,1996,12:111- 113）
Objective To investigate the early effects of intervention with tanakan on retinal function in diabetic retinopathy(DR) after laser photocoagulation. Methods Prospective random controlled study was performed on 60 Patients (60 eyes) from 23 to 69 years old with DR(phase Ⅲ～Ⅳ). The multifocal electroretinograms (MERG) were tested with VERIS Ⅳ before, the 3rd day and the 7th day after photocoagulation. Results No significant differences were found in the latencies and response densities of N1,P1 and N2 between the two groups before photocoagulation. Compared with that before photocoagulation, three days after photocoagulation the latencies in tanakan group had no significant change. The response densities of N1,P1 and N2 reduced and the changes were much smaller than that in control. Three days after photocoagulation, the response densities of P1 and N2 in the central macula 5°area were much higher and the latencies of P1 and N2 were significantly shorter than that in control group. There were no significant differences in the response densities in the 7th day and the differences in the latencies between two groups still existed. Conclusion Tanakan may be effective in preventing the retina from damage of retinal photocoagulation in some degree in DR. (Chin J Ocul Fundus Dis, 2002, 18: 208-211)
Purpose To identify matrix metalloproteinase (MMP) in human vitreous samples of diabetic vitreoretinopathy (DR) and other ocular diseases (non-DR) and to probe the related factors of MMP expression． Methods Thirty-one diabetic and 17 non-diabetic vitreous samples (nine macular hole and eight epiretinal membrane patients) were examined． Samples were concentrated and subjected to substrate zymography to conduct a quantitative analysis of MMP-2,9 activity． The technology of Western blotting against anti-human MMP-2,9 was performed to identify MMP in vitreous samples． Results Vitreous samples both from DR patients and from non-DR patients showed a single band at the position of 72 kDa, correspondin g to MMP-2． Quantitative analysis revealed that diabetic vitreous showed higher MMP-2 activity than non-DR, although the difference was not significant.45.2% of DR patients showed MMP-9, but no expression in non-DR．Among DR samples, the positive ratio of MMP-9 in partial posterior vitreous detachment (PVD)(66．7%) was significantly higher than that of complete PVD (15．4%)． Western blotting study confirmed the expression of MMP-2 and MMP-9． Conclusion There is no obvious difference of MMP-2 activity between DR and non-DR． MMP-9 may be involved in the pathogenesis of diabetic vitreor etinopathy and the deterioration of proliferative change． (Chin J Ocul Fundus Dis, 2001,17:195-197
ObjectiveTo explore the morbidity rate and risk factors of proliferative diabetic retinopathy (PDR) in type 2 diabetes.MethodsThe clinical data of patients, with PDR in 2739 consecutive cases of type 2 diabetes diagnosed in this hospital from 1994 to 2001 were analyed retospectively. The diagnosis of diabetic retinopathy (DR) was confirmed by ophthalmoscopy and fundus fluorescein angiography (FFA). Blood pressure, fasting and postprandial blood sugar, glycosylated haemoglobin（HbA1c）, total serum cholesterol, triglyceride, creatinine, and albumin excretion rate were measured.ResultsThe morbidity rate of type 2 DR was 27.8%（761/2739）, and the morbidity rate of PDR was 4.2%（114/2 739） occupying 15% of the patients with DR. The duration, fasting blood sugar, glycosylated haemoglobin, blood pressure and albumin excretion rate were much higher than those in the control（P＜0.01, glycosylated haemoglobin P＜0.05）. The independent risk factors of PDR were duration of the disease （r=0.15, P＜0.01） and albumin excretion rate （r=0.08, P＜0.05）. The risk factors of PDR were albumin excretion rate and fasting blood sugar (r=0.13, P＜0.05) in patients with longer duration(≥5 years). The morbidity rate of PDR was 2.3%, 5.9% and 12.4% in patients with duration less than 5 years, 5 to 10 years and over 10 years groups, respectively. The morbidity of PDR of the patients in normal albuminuria, microalbuminuria and overt albuminuria group was 2.1%、5.3% and 18.8% respectively.ConclusionsType 2 diabetes accompanied with PDR is relative to the duration of the diabetes, albumin excretion rate, fasting blood sugar, blood pressure, and glycosylated haemoglobin, in which the duration of the disease, albuminuria and fasting blood sugar are the risk factors of occurance of PDR. (Chin J Ocul Fundus Dis, 2003,19:338-340)
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)
ObjectiveTo systematically evaluate the potential effectiveness of JinHuang powder in the treatment of diabetic foot ulcers (DFUs). MethodsDatabases including PubMed, The Cochrane Library, Web of Science, CBM, WanFang data, VIP and CNKI were electronically searched from their inception to December 2013, to identify randomized controlled trials (RCTs) about JinHuang powder for DFUs. Two reviewers screened literature according to the inclusion and exclusion criteria, extracted data and assessed the methodological quality of included studies, and then meta-analysis was performed by using RevMan 5.1 software. ResultsA total of 3 RCTs involving 198 patients were included. The results of meta-analysis showed that:the JinHuang powder group were superior to the control group in total effective rate (RR=1.25, 95%CI 1.10 to 1.41, P=0.00) and the wound healing time (SMD=-3.32, 95%CI -5.69 to -0.96, P=0.00). ConclusionCurrent evidence suggests that the JinHuang powder is an effective therapeutic method for DFUs. Because of the limitations of quantity and quality of the eligible studies, large sample size studies are needed to validate the conclusion.
The prevalence of diabetes mellitus in adults of China has reached 12.8%. Diabetic retinopathy (DR) accounts for approximately 1/4-1/3 of the diabetic population. Several millions of people are estimated suffering the advanced stage of DR, including severe non-proliferative DR (NPDR), proliferative DR (PDR) and diabetic macular edema (DME), which seriously threat to the patients’ vision. On the basis of systematic prevention and control of diabetes and its complications, prevention of the moderate and high-risk NPDR from progressing to the advanced stage is the final efforts to avoid diabetic blindness. The implementation of the DR severity scale is helpful to assess the severity, risk factors for its progression, treatment efficacy and prognosis. In the eyes with vision-threatening DR, early application of biotherapy of anti-vascular endothelial growth factor can improve DR with regression of retinal neovascularization, but whether it is possible to induce capillary re-canalization in the non-perfusion area needs more investigation. Laser photocoagulation remains the mainstay treatment for non-center-involved DME and PDR.
ObjectiveTo observe the effects of human umbilical cord mesenchymal stem cells (hUCMSCs) on blood glucose levels and diabetic retinopathy in diabetes mellitus (DM) rats. MethodA total of 45 healthy male Sprague-Dawley rats were randomly divided into normal control group (group A, 10 rats) and DM group (33 rats). Diabetic model was established in DM group by tail vein injection of streptozotocin.The DM group was further randomly divided into 3 groups (11 rats in each group), including group B (no transplantation), group C (hUCMSC was injected through tail vein) and group D (hUCMSC was injected into the vitreous). Blood glucose, retina wholemont staining and expression of brain derived neurotrophic factor (BDNF) in the retina were measured at 2, 4, 6, 8 weeks after hUCMSC injection. The blood glucose was significantly different between A-D groups before injection (t=-64.400, -60.601, -44.065, -43.872; P=0.000) BDNF expression was studied by real time fluorescence quantitative polymerase chain reaction (RT-PCR) and immunohistochemistry staining. ResultsThe blood glucose was significantly different between A-D groups after hUCMSC injection (F=400.017, 404.410, 422.043, 344.109; P=0.000), and between group C and group B/D (t=4.447, 4.990; P < 0.01). Immuno-staining shown that BDNF was positive in ganglion cell layer (RGC) of group A, weak in group B while BDNF expression increased in group C/D. BDNF mRNA expression was significantly different between group B, C and D at 4, 6 and 8 weeks after hUCMSC injection (F=29.372, 188.492, 421.537; P=0.000), and between group B and C/D (t=66.781, 72.401, 63.880, 88.423, 75.120, 83.002; P < 0.01) by RT-PCR analysis. The BDNF mRNA expression was significantly different between C and D groups only at 8 weeks after hUCMSC injection (t=127.321, P=0.005). ConclusionsTail vein injection of hUCMSCs can significantly reduce the blood glucose levels of rats. Intravenous and intravitreal injection of hUCMSCs can increase the expression of BDNF.
ObjectiveTo observe and analyze the correlation between time within target glucose range (TIR) and hemoglobin A1c (HbA1c) and the risk of diabetic retinopathy (DR). MethodsA retrospective clinical study. From March 2020 to August 2021, 91 patients with type 2 diabetes mellitus (T2DM) who were hospitalized in Department of Endocrinology and Metabolic Diseases, Affiliated Hospital of Weifang Medical University, were included in the study. All patients underwent Oburg's no-dilatation ultra-wide-angle laser scan ophthalmoscopy, HbA1c and continuous glucose monitoring (CGM) examinations. According to the examination results and combined with the clinical diagnostic criteria of DR, the patients were divided into non-DR (NDR) group and DR group, with 50 and 41 cases respectively. The retrospective CGM system was used to monitor the subcutaneous interstitial fluid glucose for 7 to 14 consecutive days, and the TIR was calculated. Binary logistic regression was used to analyze the correlation between TIR, HbAlc and DR in patients with T2DM0. At the same time, a new indicator was generated, the predicted probability value (PRE_1), which was generated to represent the combined indicator of TIR and HbA1c in predicting the occurrence of DR. The receiver operating characteristic curve (ROC curve) was used to analyze the value of TIR, HbAlc and PRE_1 in predicting the occurrence of DR. ResultsThe TIR of patients in the NDR group and DR group were (81.58±15.51)% and (67.27±22.09)%, respectively, and HbA1c were (8.03±2.16)% and (9.01±2.01)%, respectively. The differences in TIR and HbA1c between the two groups of patients were statistically significant (t=3.501,－2.208; P=0.001, 0.030). The results of binary logistic regression analysis showed that TIR, HbA1c and DR were significantly correlated (odds ratio=0.960, 1.254; P=0.002, 0.036). ROC curve analysis results showed that the area under the ROC curve (AUC) of TIR, HbA1c and PRE_1 predicting the risk of DR were 0.704, 0.668, and 0.707, respectively [95% confidence interval (CI) 0.597-0.812, P=0.001; 95%CI 0.558-0.778, P=0.006; 95%CI 0.602-0.798, P=0.001]. There was no statistically significant difference between TIR, HbA1c and PRE_1 predicting the AUC of DR risk (P>0.05). The linear equation between HbAlc and TIR was HbAlc (%) = 11.37－0.04×TIR (%). ConclusionsTIR and HbA1c are both related to DR and can predict the risk of DR. The combined use of the two does not improve the predictive value of DR. There is a linear correlation between TIR and HbAlc.