Evaluation of VEGF gene polymorphisms and proliferative diabetic retinopathy in Mexican population

Association of Vascular Endothelial Growth Factor (VEGF) and Mouse Model Minute 2 (MDM2) Polymorphisms With Diabetic Retinopathy in a Northwest Indian Population: A Case-Control Study

INTRODUCTION

Diabetic retinopathy (DR), a microvascular complication of type 2 diabetes (T2D), results from complex interactions of genetic and environmental factors. Vascular endothelial growth factor (VEGF) and mouse model minute 2 (MDM2)are upregulated in the retina due to diabetes, which increases the risk of DR. VEGFA and MDM2 genetic variations can influence DR risk. The present case-control study was conducted to evaluate the association of VEGFA and MDM2 promoter variants with DR in a population from Punjab, Northwest India.

METHODS

A total of 414 DR patients, 425 T2D patients without DR, and 402 healthy controls were screened for VEGFA -2578C/A (rs699947), VEGFA -2549I/D (rs35569394), VEGFA -7C/T (rs25648), and MDM2 rs3730485 polymorphisms using polymerase chain reaction (PCR)-based methods.

RESULTS

VEGFA -2549 I allele (OR = 1.35 (1.00-1.81), p = 0.043) and II genotype (OR = 1.78 (1.00-3.15), p = 0.047) were significantly associated with increased risk of DR. VEGFA -7 CT genotype conferred reduced risk of DR (OR = 0.28 (0.20-0.38); p = <0.001). VEGFA -2578 and MDM2 rs3730485 showed no significant association with DR. A-I-T (OR = 0.30 (0.20-0.44); p = <0.001) and C-D-T (OR = 0.33 (0.16-0.65); p = 0.002) haplotypes of rs699947-rs35569394-rs25648 polymorphisms showed decreased risk of DR.

CONCLUSIONS

I allele and II genotype of VEGFA -2549, CT genotype of VEGFA -7, and C-I-C and A-D-C haplotypes of rs699947-rs35569394-rs25648 polymorphisms were significantly associated with DR risk in a Northwest Indian population. This is the first study worldwide to report DR risk with VEGFA promoter variants together.

Associations of VEGF Polymorphisms With Retinopathy of Prematurity

Purpose

This study investigated the associations between vascular endothelial growth factor (VEGF) polymorphisms and retinopathy of prematurity (ROP) risk.

Methods

Infants born prematurely at any time from 2009 to 2018 were included. Five single-nucleotide polymorphisms (SNPs) of VEGF were analyzed using real-time PCR in all infants. Multivariate logistic regression was applied to model the associations between VEGF polymorphisms and ROP susceptibility, severity, and premature clinicopathologic characteristics.

Results

A total of 334 patients were included and categorized into three groups: those without ROP, those with mild ROP (i.e., ROP not requiring treatment), and those with severe ROP (i.e., ROP for whom treatment was indicated). Among the female patients with ROP, those with VEGF rs3025035 CT (3.231-fold; 95% confidence interval [CI], 1.238-8.431) and a combination of CT and TT genotypes (2.643-fold; 95% CI, 1.056-6.619) exhibited significantly higher risks of severe ROP compared with those with wild-type genotypes. Female ROP infants with VEGF rs3025010 C (TC + CC) alleles had a lower risk of ROP stage ≥3 (odds ratio [OR] = 0.406; 95% CI, 0.165-0.999) than those with TT homozygotes. ROP patients with the VEGF rs10434 A allele (GA + AA) exhibited higher risks of necrotizing enterocolitis (OR = 2.750; 95% CI, 1.119-6.759) and lower risk of bronchopulmonary dysplasia (OR = 0.390; 95% CI, 0.173-0.877) than those with GG homozygotes did.

Conclusions

VEGF polymorphisms affect ROP risks differently in male and female infants. In female infants, VEGF rs3025035 with T alleles may predict ROP severity, and VEGF rs3025010 with C alleles may protect against severe ROP.

Ginsenoside Rg1 Inhibits High Glucose-Induced Proliferation, Migration, and Angiogenesis in Retinal Endothelial Cells by Regulating the lncRNA SNHG7/miR-2116-5p/SIRT3 Axis

Background

Diabetic retinopathy (DR), including retinal angiogenesis and endothelial cell proliferation and migration, is a serious complication in diabetic patients. It has been reported that ginsenoside Rg1 can prevent retinal damage. However, the mechanism by which Rg1 prevents retinal damage is unknown. Therefore, the aim of the present study was to investigate the mechanism by which Rg1 inhibits high glucose-induced complications through the regulation of the lncRNA SNHG7/miR-2116-5p/SIRT3 axis.

Methods

Under high glucose (HG) conditions, human retinal endothelial cells (HRECs) were cultured to simulate a DR environment, and Rg1 was added after 48 h. Negative control (NC), miR-2116-5p mimic, si-SNHG7, pc-DNA SIRT3, and miR-2116-5p inhibitor were transfected into HRECs, and CCK-8 assay was used to detect the cell viability. Angiogenesis and transwell assays were used to evaluate angiogenesis and cell migration, respectively. qRT-PCR and Western blot were used to detect the expression of related genes and proteins. Luciferase reporter assays and bioinformatics were used to analyze the target binding sites of miR-2116-5p to lncRNA SNHG7 and SIRT3.

Results

The proliferation, migration and angiogenesis of HRECs were induced by HG. As expected, HG upregulated miR-2116-5p and VEGF expression but downregulated lncRNA SNHG7 and SIRT3 expression. Importantly, Rg1 inhibited HG-induced HREC proliferation, migration, and angiogenesis by upregulating the lncRNA SNHG7, and miR-2116-5p had a target regulatory relationship with both lncRNA SNHG7 and SIRT3.

Conclusion

Rg1 inhibits HG-induced proliferation, migration, angiogenesis, and VEGF expression in retinal endothelial cells through the lncRNA SNG7/miR-2116-5p/SIRT3 axis. This finding provides theoretical evidence for the clinical application of Rg1 in DR.

Association of Long Noncoding RNA HOTAIR Polymorphism and the Clinical Manifestations of Diabetic Retinopathy

The aim of the current study is to evaluate the possible correlation between the single-nucleotide polymorphisms (SNP) of HOX transcript antisense intergenic RNA (HOTAIR) and the clinical characteristics of diabetic retinopathy (DR). Four loci of HOTAIR SNPs, including rs920778 (T/C), rs12427129 (C/T), rs4759314 (A/G), and rs1899663 (G/T), were genotyped via the TaqMan allelic discrimination for 276 DR individuals and 452 non-DR patients. The distribution frequency of HOTAIR SNP rs12427129 CT [adjusted odds ratio (AOR): 1.571, 95% CI: 1.025-2.408, p = 0.038], HOTAIR SNP rs12427129 CT+TT (AOR: 1.611, 95% CI: 1.061-2.446, p = 0.025), and HOTAIR SNP rs1899663 TT (AOR: 2.443, 95% CI: 1.066-5.595, p = 0.035) were significantly higher in the DR group. Moreover, the proliferative diabetic retinopathy (PDR) subgroup revealed a significantly higher distribution of HOTAIR SNP rs12427129 CT+TT (AOR: 2.016, 95% CI: 1.096-3.710, p = 0.024) and HOTAIR SNP rs1899663 TT (AOR: 4.693, 95% CI: 1.765-12.479, p = 0.002), and the distribution frequencies of HOTAIR SNP rs12427129 CT (AOR: 3.722, 95% CI: 1.555-8.909, p = 0.003), HOTAIR SNP rs12427129 CT+TT (AOR: 4.070, 95% CI: 1.725-9.600, p = 0.001), and HOTAIR SNP rs1899663 TT (AOR: 11.131, 95% CI: 1.521-81.490, p = 0.018) were significantly higher in the female PDR subgroup. Regarding the clinical characters, the DR patients with HOTAIR SNP rs1899663 GT+TT revealed a significantly shorter duration of diabetes compared to the DR patients with HOTAIR SNP rs1899663 GG (10.54 ± 8.19 versus 12.79 ± 7.73, p = 0.024). In conclusion, HOTAIR SNP rs12427129 and rs1899663 are strongly correlated to the presence of DR, especially for a female with PDR.

Study on BCVA, CMT, CME, Curative Effect, and Prognostic Value of DR Sufferers Based on Surgical Therapy Combined with VEGF Therapy at Different Times

In order to explore the efficacy and prognostic value of best corrected visual acuity (BCVA), central macular retinal thickness (CMT), and cystoid macular edema (CME) in diabetic retinopathy (DR) sufferers based on surgical therapy combined with vascular endothelial growth factor (VEGF) therapy at different times, a total of 170 cases of DR sufferers who visited our hospital from March 2019 to March 2021 are analyzed. All patients are randomly divided into control group and study group, with 85 cases and 85 eyes in each group. In addition, the contrast set received 2 therapies for 1.5 months/time, and the study set received 3 therapies for 1 month/time. The experimental results show that the BCVA of the two sets is notoriously enhanced. Besides, CMT and CME in the study set decrease more than those in the contrast set, and the blood vessel density of retinal capillaries in the contrast set and the examination set is notoriously enhanced. For DR sufferers, 1 month/time of anti-VEGF therapy can effectively enhance the sufferers’ visual acuity, CMT and CME. It is suggested that the clinical application of 1 month/time of anti-VEGF to DR sufferers can enhance the clinical therapeutic effect of sufferers and reduce the prognosis and recurrence.

A study of the genotyping and vascular endothelial growth factor polymorphism differences in diabetic and diabetic retinopathy patients

Background

Retinopathy is one of the major causes of visual impairment which is the most severe microvascular complication of diabetes mellitus (DM). The aim of this study was to evaluate the association between diabetic retinopathy (DR) and two SNPs (− 152G > A and − 165C > T) located in the promoter region of the vascular endothelial growth factor (VEGF) gene in a small sample from Egyptian population. One hundred diabetic patients without retinopathy (DWR) and two hundred diabetic patients with retinopathy were included in this study. Genotype analysis for the two SNPs (− 152G > A and − 165C > T) was assessed by using the PCR–RFLP technique. In addition, the serum protein level of VEGF was measured by ELISA assay.

Results

The results showed a significant relationship between − 152G > A (rs13207351) polymorphism and both proliferative and non-proliferative retinopathy in genotypes (GG, GA, AA). The risk factor increment in the mutant heterozygous genotype (GA) was significantly increased in NPDR compared to PDR (OR = 16.3, 95%CI = 0.80–331.7); (OR = 20.4, 95%CI = 1.08–385.3), respectively. There was no significance between VEGF − 165C > T (rs79469752) gene polymorphism and retinopathy. Moreover, the serum protein level of VEGF showed a highly significant increase (P = 0.0001) in PDR (Mean ± SD = 3691 ± 124.9) when compared to both DWR (Mean ± SD = 497.3 ± 18.51) and NPDR (Mean ± SD = 1674.5 ± 771.7). These results were supported by the increased level of VEGF in serum protein which is positively correlated with the severity of retinopathy. Measuring VEGF protein level in DR patients would help as a biomarker in early diagnosis.

Conclusion

The increase in the mutant heterogeneous GA genotype in VEGF − 152G > A SNP could be a risk factor for the progression of severe retinopathy in diabetic patients.

Genetics of Diabetic Retinopathy, a Leading Cause of Irreversible Blindness in the Industrialized World

Diabetic retinopathy (DR) is a chronic complication of diabetes and a leading cause of blindness in the industrialized world. Traditional risk factors, such as glycemic control and duration of diabetes, are unable to explain why some individuals remain protected while others progress to a more severe form of the disease. Differences are also observed in DR heritability as well as the response to anti-vascular endothelial growth factor (VEGF) treatment. This review discusses various aspects of genetics in DR to shed light on DR pathogenesis and treatment. First, we discuss the global burden of DR followed by a discussion on disease pathogenesis as well as the role genetics plays in the prevalence and progression of DR. Subsequently, we provide a review of studies related to DR’s genetic contribution, such as candidate gene studies, linkage studies, and genome-wide association studies (GWAS) as well as other clinical and meta-analysis studies that have identified putative candidate genes. With the advent of newer cutting-edge technologies, identifying the genetic components in DR has played an important role in understanding DR incidence, progression, and response to treatment, thereby developing newer therapeutic targets and therapies.

Sirtuin (Sirt) 3 Overexpression Prevents Retinopathy in Streptozotocin-Induced Diabetic Rats

BACKGROUND Sirtuin (Sirt) 3 could promote autophagy by downregulating the expression of genes related to neovascularization in retinal endothelial cells. In this study, we aimed to investigate the effect of Sirt3 overexpression on retinopathy in streptozotocin (STZ)-induced diabetic rats, and to assess its mechanisms. MATERIAL AND METHODS Ntraperitoneal injection of STZ in rats was used to produce a diabetic model. The study rats were divided into 4 groups (n=6 for each group): a control group; a model group; a model+scrambled adenovirus group; and a model+Sirt3 overexpression group. Hematoxylin and eosin (H&E) staining determined the pathological changes of retina tissues. Immunohistochemistry, fluorescence quantitative polymerase chain reaction, and western blotting were used to detect the expression of Sirt3, vascular endothelial growth factor (VEGF), and microtubule-associated protein 1A/1B-light chain 3 (LC3). RESULTS In the model group, the inner limiting membrane was swollen, uneven and thickened, and the capillary endothelial cells occasionally protruded into the inner limiting membrane. These abnormalities were prevented by Sirt3 overexpression. Compared with the control group, the expression of Sirt3 at both mRNA and protein levels in the model group was significantly reduced, while the expression of VEGF was increased versus the control group (P.

Meta-analysis of the association between aldose reductase gene (CA)n microsatellite variants and risk of diabetic retinopathy

Diabetic retinopathy (DR) is one of the most severe microvascular complications of diabetes mellitus (DM). The (CA)n microsatellite variation of the aldose reductase (ALR) gene has been indicated to be associated with DR in previous studies; however, the results were inconclusive. To provide a more precise evaluation of the association between the (CA)n variations of ALR and the risk for DR, a meta-analysis was performed in the present study. Relevant articles were retrieved from the PubMed, Embase, Chinese National Knowledge Infrastructure and Cochrane Library databases. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the strength of the associations. The present meta-analysis included 17 studies comprising 1,575 DM patients with retinopathy and 1,741 DM patients without retinopathy. The results indicated that the Z-2 allele was a risk factor for DR in Asian (OR=1.82, 95% CI: 1.16-2.86, P=0.009) and Caucasian (OR=2.08, 95% CI: 1.14-3.79, P=0.02) populations, as well as in type 1 diabetes (T1D; OR=3.42, 95% CI: 1.46-8.04, P=0.005) and type 2 diabetes (T2D; OR=1.66, 95% CI: 1.05-2.63, P=0.03). Furthermore, the Z+2 allele was determined to be a protective factor for DR in Caucasian individuals (OR=0.50, 95% CI: 0.34-0.73, P=0.0004) and those with T1D (OR=0.39, 95% CI: 0.27-0.57, P<0.00001). Z+4 was also identified to be a protective factor, reducing the risk of DR in patients with T1D (OR=0.74, 95% CI: 0.57-0.96, P=0.02). Z-4 was revealed to be a risk factor for DR in Asian populations (OR=1.57, 95% CI: 1.22-2.03, P=0.0005) and in individuals with T1D (OR=1.62, 95% CI: 1.27-2.08, P=0.0001). However, no association was detected between the Z, Z+6 and Z-6 alleles and the risk of DR (P>0.05). In conclusion, the present results revealed the following: Z+2 may serve as a protective factor for DR in Caucasian individuals and those with T1D; Z+4 may be a protective factor for DR in patients with T2D; Z-2 may represent a risk factor for DR in all subgroups analyzed; and Z-4 may be a risk factor for DR in Asian populations and patients with T2D.

Oxidative Stress as the Main Target in Diabetic Retinopathy Pathophysiology

Diabetic retinopathy (DR) is one of the most common complications of diabetes mellitus (DM) causing vision impairment even at young ages. There are numerous mechanisms involved in its development such as inflammation and cellular degeneration leading to endothelial and neural damage. These mechanisms are interlinked thus worsening the diabetic retinopathy outcome. In this review, we propose oxidative stress as the focus point of this complication onset.

Surgical Versus Medical Treatment for Diabetic Macular Edema: A Review

We aimed to compare the results of pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling, an alternative therapeutic strategy, with those of medical treatment for chronic macular edema. We conducted a review of the literature on the microscopic, anatomical, and functional reasons for performing PPV with ILM peeling in patients with diabetic macular edema (DME). We searched the PubMed database for articles published between 2000 and 2017. We used the medical subject heading "vitrectomy diabetic macular edema" and the keywords "diabetic macular edema", "internal limiting membrane peeling", "pars plana vitrectomy", "diabetic retinopathy", and "optical coherence tomography". Analysis of the literature revealed that cytokines, vascular endothelial growth factor, reactive oxygen species (ROS), and advanced glycation end-products (AGEs) play a unique role in DME. The vitreous cavity serves as a physiological reservoir for all inflammatory molecules. AGE receptors are localized at the footplates of Müller cells and the external limiting membrane (ELM). The footplates of Müller cells are in contact with the ILM, which suggests that they might be responsible for the structural damage (i.e., thickening) observed in the ILM of patients with DME. Therefore, PPV could allow a reduction of cytokines and pro-inflammatory molecules from the vitreous cavity. ILM peeling could eliminate not only the physical traction of a thickened structure, but also the natural reservoir of AGEs, ROS, and inflammatory molecules. PPV with ILM peeling is a surgical option that should be considered when treating patients with chronic DME.