Objective To observe the serum betatrophin levels in patients with type 2 diabetes mellitus (T2DM) and to explore the role of betatrophin in the pathogenesis of diabetic retinopathy (DR). Methods A total of 59 patients with T2DM (DM group) and 14 healthy controls (NC group) were enrolled in the study. Vision, slit lamp microscope, indirect ophthalmoscope, fluorescein fundus angiography were performed on all the subjects. According to the results of the examination combined with the international DR clinical staging criteria, the patients were divided into no DR (Non-DR) group, non-proliferative DR (NPDR) group, and proliferative DR (PDR) group, with 30, 20 and 9 patients in each, respectively. The fasting blood glucose (FPG), insulin (FIN), C-peptide, glycated hemoglobin (HbA1c), total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL-C), low-density lipid Protein (LDL-C) levels were detected. The level of betatrophin in serum was determined by enzyme-linked immunosorbent assay. The correlation between betatrophin and other indicators was analyzed by Spearman correlation. The influencing factors of PDR were analyzed by logistic regression. Results Compared with subjects in the NC group, the level of FPG (F=-4.316, P＜0.001), FIN (F=2.142, P=0.001), HbA1c (F=-5.726, P＜0.001), TC (t=3.609, P=0.010), LDL-C (t=0.000, P=0.003), and betatrophin (F=-2.263, P=0.024) were significantly increased and HDL-C level (F=-3.924, P＜0.001) was decreases in the DM group. The difference of TG level between two groups was not statistically significant (F= -1.422, P=0.155). Compared with the Non-DR group and the NPDR group, the serum C-peptide (F=7.818, P=0.020) and betatrophin levels (F=12.141, P=0.002) were significantly increased in the PDR group. Spearman correlation analysis showed that the levels of betatrophin in the DM group was positively correlated to TC (r=0.304, P=0.019). The serum levels of betatrophin was positively correlated to body mass index in the Non-DR group (r=0.513, P=0.004). Furthermore, in the PDR group, a significant positive correlation was observed between the serum betatrophin levels and diastolic blood pressure (r=0.685, P=0.042). Logistic regression analysis showed that the duration of diabetes, serum C-peptide and betatrophin levels were risk factors for PDR. After controlling for the duration and serum C-peptide, the PDR risk for betatrophin levels great than or equal to 1.0 ng/ml was 12 times as much as betatrophin levels less than 1.0 ng/ml in T2DM patients. Conclusions The serum betatrophin content of patients with T2DM is abnormal. Betatrophin may be involved in the occurrence and development of PDR.
ObjectiveTo investigate the expression and mechanism of miR-1470 in plasma of diabetic retinopathy (DR) patients.MethodsThirty patients with DR (DR group), 30 patients with diabetes (DM group) and 30 normal healthy subjects (normal group) were enrolled in the study. Three groups of subjects were taken 5 ml of venous blood, and total plasma RNA was extracted and purified. The differentially expressed miRNAs in the plasma of DR patients were screened by gene chip, and the results of gene chip detection were verified by reverse transcription polymerase chain reaction (RT-PCR). Bioinformatics was used to predict potential target genes for miRNA regulation, and miR-1470 and its target gene epidermal growth factor receptor (EGFR) were screened. Human retinal microvascular endothelial cells (hREC) were divided into normal group (sugar concentration 5.5 mmol/L) and high glucose group (sugar concentration 25.0 mmol/L). hREC was transfected into miR-1470 mimics to establish a miR-1470 high expression cell model, which was divided into blank control group, high expression group and negative control group. The expression of miR-1470 was detected by RT-PCR. The expression of EGFR protein was detected by Western blot. The measurement data of the two groups were compared using the independent sample t test. The comparison of the measurement data between the two groups was analyzed by ANOVA. The comparison between the measurement data of the groups was compared by multiple comparisons.ResultsThe results of RT-PCR were consistent with those of the gene chip. The expression of miR-1470 in the plasma of the DR group, the DM group and the normal group was statistically significant (F=63.486, P=0.049). Compared with the DM group and the normal group, the expression of miR-1470 in the DR group was significantly decreased, and the difference was statistically significant (q=111.2, 73.9; P＜0.05). The expression of miR-1470 in hREC in the high glucose group was significantly lower than that in the normal group (t=42.082, P=0.015). The expression of EGFR protein in hREC of high glucose group was significantly higher than that of normal group (t=−39.939, P=0.016). The expression of miR-1470 (F=637.069, P=0.000) and EGFR (F=122.908, P=0.000) protein expression in hREC of blank control group, negative control group and high expression group were statistically significant . Compared with the blank control group and the negative control group, the expression of miR-1470 in hREC of high expression group was significantly increased (q=329.7, 328.8; P＜0.05), and the expression of EGFR protein was significantly decreased (q=242.5, 234.6; P＜0.05). There was no significant difference in the expression of miR-1470 and EGFR protein in hREC between the negative control group and the blank control group (q=1.5, 7.9; P＞0.05).ConclusionThe expression of miR-1470 in the plasma of patients with DR is significantly down-regulated, and the increase of EGFR expression may be related to it.
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.
ObjectiveTo observe the serum vascular endothelial growth factor (VEGF), apelin and heme oxygenase-1 (HO-1) levels in patients with type 2 diabetes mellitus (T2DM) and to explore their their relationship with diabetic retinopathy (DR).MethodsA total of 208 patients with T2DM and 50 healthy subjects (control group) from the Central Hospital of Western Hainan during January 2014 and December 2017 were selected in this study. Vision, slit lamp microscope, indirect ophthalmoscope and FFA examinations were performed on all the subjects. According to the results of the examinations combined with the DR clinical staging criteria, the patients were divided into non-DR (NDR) group, non-proliferative DR (NPDR) group, and proliferative DR (PDR) group, with 72, 76 and 60 patients in each, respectively. The clinical data of each group were recorded, and the levels of fasting blood glucose (FPG), HbA1c, total cholesterol (TC), three acylglycerol (TG), high density lipoprotein (HDL-C), low density lipoprotein (LDL-C), VEGF, apelin and HO-1 were detected in each group. The receiver operating characteristic curve (ROC) were used to analyze the value of VEGF, apelin and HO-1 in predicting the occurrence of PDR. Correlation analysis of serum VEGF, Apelin and HO-1 with clinical parameters in PDR patients by Pearson correlation analysis.ResultsThe level of VEGF (56.82±10.16 vs 91.74±22.83, 140.15±36.40, 195.28±42.26 pg/ml) and apelin (2.95±0.53 vs 4.68±0.74, 7.25±1.13, 10.16±1.35 ng/ml) in PDR group were significantly higher than those in NPDR, NDR and control groups (F=17.306, 21.814; P＜0.05). The level of HO-1 (50.37±10.14 vs 43.58±8.16, 30.25±6.28, 22.60±4.72 mmol/L) in PDR group was significantly lower than those in NPDR, NDR and control groups (F=15.827, P＜0.05). The ROC curve analysis showed that the best cut-off values of serum VEGF, apelin and HO-1 were 162.50 pg/ml, 8.30 ng/ml, 27.13 mmol/L, and the three combined to predict PDR of AUC (95%CI) was 0.906 (0.849−0.962), and their sensitivity (90.3%) and specificity (83%) were better. The correlation analysis showed that the VEGF, apelin and HO-1 of PDR patients were correlated with the course of diabetes (r=0.382, 0.416, −0.36; P＜0.05), FPG (r=0.438, 0.460, −0.397; P＜0.05) and HbAlc (r=0.375, 0.478, −0.405; P＜0.05), and the serum VEGF were correlated with apelin and HO-1 (r=0.793, −0.594; P＜0.01).ConclusionElevated serum VEGF and apelin levels and reduced HO-1 levels are associated with the progression of DR, and the three combination helps predict the occurrence of PDR.
Objective To analyze the expression of apoptosis-related genes of retinal blood vessel in early diabetic rats by gene chip technology. Methods To make diabetic rat model by intraperitoneal injection of streptozotocin (STZ). On the 6th week after blood pressure increased, 10 rats were executed in Diabetic group and normal control group respectively. 20 retinal blood vessels were extracted and the RNA was isolated. The probe was made of alpha;-32 P-deoxyadenosine triphosphate (dATP)-labeled sample which hybridized 1176 nylon chips, and then analyzed by software. Three different expression genes were selected to verify by reverse transcription polymerase chain reaction (RT-PCR). Results On the 6th week, 136 （11.5％） genes were differentially expressed ［up-regulated genes were 90(7.6%), down-regulated genes were 46(3.9%)］in diabetic group. These genes involved into different groups according to their function. Especially in 72 apoptosis-related genes, 15 genes were differentially expressed. The up-regulated genes were some TNF receptor family members such as TNFRSF12, TRAIL, TNFRSF9, FADD；Bcl-2 family members such as bcl-w, bax, bak1 and AKT. The down-regulated genes were FAF1 which related to fas. Conclusions The expression of retinal vascular gene in early diabetic rats has been changed complicatedly. In particular, the multiple apoptosis-related genes have been changed in early diabetic, and most of them are at the upstream of apoptosis pathway. These findings indicate that the development of diabetic retinopathy is associated with multiple signaling pathways leading to apoptosis, while the alterations on the level of molecular biochemistry are still limited in apoptosis induction period. （Chin J Ocul Fundus Dis，2008，24：244-248）
ObjectiveTo investigate the expression of miR-195 and the underlying molecular mechanisms of miR-195 regulating HMGB1 in diabetic retinopathy (DR). MethodsExtract 5 ml venous blood from DR patients, diabetes mellitus (DM) patients and normal subjects, then extract and perificate plasma total RNA. MicroRNA array and real time polymerase chain reaction (RT-PCR) was used to screen out miRNAs which were expressed with significant differences in the serum of patients with DR. Bioinformatics was employed to predict the miR-195 related to high mobility group box 1 (HMGB1) regulation. Next, miR-195 was down-regulated or up-regulated in umbilical vein endothelial cells through transfection of miR-195 inhibitor and miR-29b mimics respectively.Then we analyzed expression of HMGB1 mRNA and protein by RT-PCR and Western blot. ResultsMicroRNA array results showed the expression of miR-195 in DR group is decreased by 8.34 times and 11.47 times compared with DM group and the normal group. RT-PCR verification results conforms to the microRNA array results. Compared with the DM group (F=0.034, t=8.057) and the normal group (F=0.370, t=9.522), the expression of miR-195 in DR group were significantly reduced, the differences were statistically significant (P < 0.05). RT-PCR showed that the expression of HMGB1 mRNA was significantly decreased in up-regulation group, compared with blank (F=0.023, t=11.287) and negative control group (F=0.365, t=7.471), the difference was statistically significant (P < 0.05). The expression of HMGB1 mRNA was significantly increased in down-regulation group, compared with blank (F=0.053, t=10.871) and negative control group (F=0.492, t=6.883), the difference was statistically significant (P < 0.05). Western blot showed that the expression of HMGB1 protein was significantly decreased in up-regulation group, compared with blank (F=0.021, t=8.820) and negative control group (F=0.039, t=7.401), the difference was statistically significant (P < 0.05); and significantly increased in down-regulation group, compared with blank (F=0.186, t=10.092) and negative control group (F=0.017, t=12.923), the difference was statistically significant (P < 0.05). ConclusionMiR-195 can inhibit the expression of HMGB1, reduce the inflammation and angiogenesis, thereby delaying or inhibiting the occurrence and development of DR.