Anti-vascular endothelial growth factor drugs combined with laser photocoagulation maintain retinal ganglion cell integrity in patients with diabetic macular edema: study protocol for a prospective, non-randomized, controlled clinical trial

The integrity of retinal ganglion cells is tightly associated with diabetic macular degeneration that leads to damage and death of retinal ganglion cells,affecting vision.The major clinical treatments for diabetic macular edema are anti-vascular endothelial growth factor drugs and laser photocoagulation.However,although the macular thickness can be normalized with each of these two therapies used alone,the vision does not improve in many patients.This might result from the incomplete recovery of retinal ganglion cell injury.Therefore,a prospective,non-randomized,controlled clinical trial was designed to investigate the effect of anti-vascular endothelial growth factor drugs combined with laser photocoagulation on the integrity of retinal ganglion cells in patients with diabetic macular edema and its relationship with vision recovery.In this trial,150 patients with diabetic macular edema will be equally divided into three groups according to therapeutic methods,followed by treatment with anti-vascular endothelial growth factor drugs,laser photocoagulation therapy,and their combination.All patients will be followed up for 12 months.The primary outcome measure is retinal ganglion cell-inner plexiform layer thickness at 12 months after treatment.The secondary outcome measures include retinal ganglion cell-inner plexiform layer thickness before and 1,3,6,and 9 months after treatment,retinal nerve fiber layer thickness,best-corrected visual acuity,macular area thickness,and choroidal thickness before and 1,3,6,9,and 12 months after treatment.Safety measure is the incidence of adverse events at 1,3,6,9,and 12 months after treatment.The study protocol hopes to validate the better efficacy and safety of the combined treatment in patients with diabetic macula compared with the other two monotherapies alone during the 12-month follow-up period.The trial is designed to focus on clarifying the time-effect relationship between imaging measures related to the integrity of retinal ganglion cells and best-corrected visual acuity.The trial protocol was approved by the Medical Ethics Committee of the Affiliated Hospital of Beihua University with approval No.(2023)(26)on April 25,2023,and was registered with the Chinese Clinical Trial Registry(registration number:ChiCTR2300072478,June 14,2023,protocol version:2.0).

Role of serum β2-microglobulin, glycosylated hemoglobin, and vascular endothelial growth factor levels in diabetic nephropathy

BACKGROUND Diabetic nephropathy(DN)is a common complication of type 1 and type 2 diabetes that can lead to kidney damage and high blood pressure.Increasing evidence support the important roles of microproteins and cytokines,such asβ2-microglobulin(β2-MG),glycosylated hemoglobin(HbA1c),and vascular endothelial growth factor(VEGF),in the pathogenesis of this disease.In this study,we identified novel therapeutic options for this disease.AIM To analyze the guiding significance ofβ2-MG,HbA1c,and VEGF levels in patients with DN.METHODS A total of 107 patients with type 2 diabetes mellitus complicated with nephropathy and treated in our hospital from May 2018 to February 2021 were included in the study.Additionally,107 healthy individuals and 107 patients with simple diabetes mellitus were selected as the control groups.Changes inβ2-MG,HbA1c,and VEGF levels in the three groups as well as the different proteinuria exhibited by the three groups were examined.RESULTS Changes inβ2-MG,HbA1c,and VEGF levels in the disease,healthy,and simple diabetes groups were significantly different(P<0.05).The expression of these factors from high to low were evaluated in different groups by pairwise comparison.In the disease group,high to low changes inβ2-MG,HbA1c,and VEGF levels were noted in the massive proteinuria,microproteinuria,and normal urinary protein groups,respectively.Changes in these factors were positively correlated with disease progression.CONCLUSION The expression of serumβ2-MG,HbA1c,and VEGF was closely correlated with DN progression,and disease progression could be evaluated by these factors.

Vascular endothelial growth factor/connective tissue growth factor and proteomic analysis of aqueous humor after intravitreal conbercept for proliferative diabetes retinopathy

AIM:To investigate the role of connective tissue growth factor(CTGF)and vascular endothelial growth factor(VEGF)in the protein profile of the aqueous humor in patients with proliferative diabetic retinopathy(PDR)following intravitreal injection of conbercept.METHODS:This study included 72 PDR patients and 8 cataract patients as controls.PDR patients were divided into 3 groups according to the intervals of 3,5,and 7d between intravitreal conbercept(IVC,0.5 mg/0.05 mL)injection and pars plana vitrectomy(PPV)performed.Aqueous humor samples were collected before and after IVC and PPV for VEGF and CTGF levels detected with enzyme-linked immunosorbent assay(ELISA).The differential proteomics of 10 patients who underwent PPV surgery 5d after IVC and 8 normal controls was studied,Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis were performed on the data,and the protein interaction network of 23 differential proteins was studied.RESULTS:Post-IVC,VEGF levels decreased and CTGF levels increased significantly in aqueous humor,with the CTGF/VEGF ratio rising significantly at all intervals.Liquid chromatography tandem mass spectrometry(LC-MS/MS)identified differentially expressed proteins between preand post-IVC samples.GO and KEGG analyses revealed involvement in immune response,stress response,complement and coagulation cascades,ferroptosis,and PPAR signaling pathways.PPI analysis highlighted key proteins like APOA1,C3,and transferrin(TF).ELISA assay confirmed the differential expression of proteins such as HBA1,SERPINA1,COL1A1,and ACTB,with significant changes in the IVC groups.CONCLUSION:The study demonstrates that IVC effectively reduces VEGF levels while increasing CTGF levels,thereby modifying the CTGF/VEGF ratio,and IVC significantly alters the protein profile in the aqueous humor of patients with PDR.Proteomic analysis reveals that these changes are associated with critical biological pathways and protein interactions involved in immune response,stress response,and cellular metabolism.

Expression and significance of angiostatin, vascular endothelial growth factor and matrix metalloproteinase-9 in brain tissue of diabetic rats with ischemia reperfusion

Objective: To discuss the expression and significance of angiostatin, vascular endothelial growth factor and matrix metalloproteinase-9 in the brain tissue of diabetic rats with ischemia reperfusion. Methods: A total of 60 male Wistar rats were randomly divided into the normal group, sham group, diabetic cerebral infarction group and single cerebral infarction group according to the random number table, with 15 rats in each group. The high sucrose diet and intraperitoneal injection of streptozotocin were performed for the modeling of diabetic rats, while the thread-occlusion method was employed to build the model of cerebral ischemia reperfusion. The immunohistochemical staining was performed to detect the expression of angiostatin, vascular endothelial growth factor(VEGF) and matrix metalloproteinase-9(MMP-9) in the brain tissue. Results: The expression of angiostatin after the reperfusion in the brain tissue of rats in the single cerebral infarction group and diabetic cerebral infarction group was increased 6 h after the reperfusion, reached to the peak on 1 d and then decreased gradually. The expression of angiostatin in the diabetic cerebral infarction group 6 h, 1 d, 3 d and 7 d after the reperfusion was significantly higher than that in the single cerebral infarction group(P<0.05). VEGF began to be increased 1 h after the reperfusion in the single cerebral infarction group and diabetic cerebral infarction group, reached to the peak at 6 h and then decreased gradually. The expression of VEGF in the diabetic cerebral infarction group at each time point after the reperfusion was significantly lower than that in the single cerebral infarction group(P<0.05). MMP-9 began to be be increased 1 h after the reperfusion in the single cerebral infarction group and diabetic cerebral infarction group, reached to the peak on 1 d and then decreased gradually. The expression of MMP-9 in the diabetic cerebral infarction group at each time point after the reperfusion was significantly higher than that in the single cerebral infarction group(P<0.05). Conclusions: The high glucose environment in which the diabetic cerebral infarction is occurred is to induce the formation of MMP-9 at first and then activate and increase the expression of angiostatin. Afterwards, the expression of VEGF is inhibited, resulting in the poor angiogenesis after cerebral infarction, which thus makes the injury of brain tissue after cerebral infarction even worse than the non-diabetes mellitus.

Vascular endothelial growth factor trap-eye(Aflibercept) for the management of diabetic macular edema

Diabetic retinopathy(DR)is the most common cause of visual loss among working age individuals.Diabetic macular edema(DME)is an important complication of DR that affects around one third of the patients with DR.Several treatments have been approved for DME ranging from blood pressure and glycemic control to photocoagulation and more recently the use of vascular endothelial growth factor(VEGF)antagonists.The index review discusses aflibercept(EYLEA-Regeneron Pharmaceuticals,Inc.,Tarrytown,New York,NY,and Bayer Healthcare Pharmaceuticals,Berlin,Germany)in the context of other VEGF antagonists currently available for the treatment of DME.A systematic search of literature was conducted on PubMed,Scopus,and Google Scholar with no limitation on language or year of publication.Pre-clinical studies of aflibercept have shown a higher affinity of this molecule for vascular endothelial growth factor A(VEGF-A)along with a longer duration of action as compared to other VEGF antagonists.Recent clinical trials have shown visual outcome results for aflibercept to be similarly favorable as compared to other available agents with the added benefit of fewer required injections and less frequent monitoring.Aflibercept presents a potential exciting new addition to the armamentarium of current VEGF antagonists available for the treatment of DME and other retinal vascular diseases.However,further studies are indicated to confirm the role,safety,and efficacy of aflibercept for DME.

Streptozotocin induced diabetic retinopathy in rat and the expression of vascular endothelial growth factor and its receptor

·AIM: To establishtherat model of streptozotocin (STZ)- induced diabetic retinopathy (DR), which is the most common cause of visual loss and blindness in patients with diabetes, and observe the gene expression of vascular endothelial growth factor (VEGF) and its receptors during the development of DR. ·METHODS: A rat model of diabetes was established by intraperitoneal injection of STZ. The diabetic rats were housed for 2, 3 and 4 months after the development of diabetes. Retinal histopathological observation was performed. The retinal vessels were observed by immunofluorescence staining by CD31. The mRNA expression of VEGF, VEGF receptor 1 and 2 (VEGFR1/2) in rat retina was detected by reverse transcription - polymerase chain reaction (RT-PCR) analysis. · RESULTS: Retinal histopathological observation showed the morphological changes of inner nuclear layer (INL) and outer nuclear layer (ONL) at any time -point, and also demonstrated the increased new vessels at both 3, 4 months after the development of diabetes. The CD31 staining results showed that the number of vessels was increased in the retinas of diabetic rats at both 3 and 4 months after the development of diabetes. As compared to the normal rats, the mRNA expression of VEGF was increased in retinas of diabetic rats at 3 months after the development of diabetes, while VEGFR1 and VEGFR2 mRNA expression was increased at 2, 3 and 4 months after the development of diabetes.·CONCLUSION:Takentogether,ourresultsdemonstrated that DR was occurred at 3 months after the development of diabetes, and the mRNA expression of VEGF, VEGFR1 and VEGFR2 were increased in the process of DR. The present study further evidenced the involvement of VEGF and its receptors in the process of DR. ·

Effect of periocular injection of celecoxib and propranolol on ocular level of vascular endothelial growth factor in a diabetic mouse model

AIM： To investigate the effects of periocular injection of propranolol and celecoxib on ocular levels of vascular endothelial growth factor （VEGF） in a diabetic mouse model. METHODS： Forty 4-6wk BALB-C male mice weighing 20-25 g were used. The study groups included： nondiabetic control （group 1）, diabetic control （group 2）, diabetic propranolol （group 3）, and diabetic celecoxib （group 4）. After induction of type 1 diabetes by streptozotocin, propranolol （10 μg） and celecoxib （200 μg dissolved in carboxymethylcellulose 0.5%） were injected periocularly. The ocular level of VEGF was measured in all the study groups using enzyme-linked immuno sorbent assay （ELISA） method. RESULTS： Ocular VEGF level was significantly increased （1.25 fold） in the diabetic control group when compared to the non-diabetic group one week after induction with streptozotocin （P=0.002）. Both periocular propranolol and celecoxib significantly reduced ocular VEGF levels （P=0.047 and P〈0.001, respectively）. The effect was more pronounced with celecoxib, CONCLUSION： The periocular administration of propranolol and celecoxib can significantly reduce ocular VEGF levels in a diabetic mouse model.

Efficacy and mechanism of anti-vascular endothelial growth factor drugs for diabetic macular edema patients

BACKGROUND Diabetes is a serious public health concern in China,with 30%of patients developing retinopathy,and diabetic macular edema(DME)having the biggest impact on vision.High blood glucose level can cause retinal cell hypoxia,thus promoting vascular endothelial growth factor(VEGF)formation and increasing vascular permeability,which induces DME.Moreover,cell hypoxia can accelerate the rate of apoptosis,which leads to the aging of patients.In severe cases,optic cell apoptosis or retinal fibrosis and permanent blindness may occur.AIM To investigate and compare the efficacy,mechanism,and differences between two anti-VEGF drugs(Compaq and ranibizumab)in DME patients.METHODS Ninety-six patients with DME who attended our hospital from April 2018 to February 2020 were included and randomly divided into two groups(Compaq group and ranibizumab group).The groups received vitreal cavity injections of 0.5 mg Compaq and 0.5 mg ranibizumab,respectively,once a month.The best corrected visual acuity(BCVA),intraocular pressure(IOP),macular retinal thickness(CMT),macular choroidal thickness(SFCT),foveal no perfusion area(FAZ),superficial capillary density,deep capillary density,treatment effect,and adverse reactions were compared before and after treatment and between the two groups.RESULTS Before treatment and 1-mo post-treatment,there was no statistically significant difference in the estimated BCVA in both groups(P>0.05).BCVA decreased in the Compaq group 3 mo after treatment,and the difference was statistically significant(P<0.05).Before treatment,and 1 mo and 3 mo post-treatment,there was no statistically significant difference in the estimated IOP in either group(P>0.05).Before treatment and 1-mo post-treatment,there was no statistically significant difference in the estimated CMT,SFCT,or FAZ in either group(P>0.05).CMT and SFCT values decreased in the Compaq group 3 mo post-treatment,and the difference was statistically significant(P<0.05).Before treatment,and 1 mo and 3 mo post-treatment,there were no statistically significant differences in vascular density in the shallow or deep capillary plexi of the fovea,parafovea,or overall macular area between the two groups(P>0.05).Marked efficient,effective,and invalid rates were 70.83%and 52.08%,27.08%and 39.58%,and 2.08%and 8.33%in the Compaq and ranibizumab groups,respectively.The differences between the two groups were statistically significant(P<0.05).CONCLUSION Anti-VEGF drugs can effectively improve CMT and SFCT,without affecting microcirculation,thus providing an effective and safe treatment for patients with DME.

Association of vascular endothelial growth factor-634G/C and receptor for advanced glycation end products G82S gene polymorphisms with diabetic retinopathy

AIMTo investigate the association of receptor for advanced glycation end products (RAGE) G82S and vascular endothelial growth factor (VEGF) -634 G/C gene polymorphisms with diabetic retinopathy (DR).METHODSOur cross-sectional study included 61 diabetic patients, 12 of them had proliferative diabetic retinopathy (PDR), 15 had non proliferative diabetic retinopathy (NPDR), 34 had no diabetic retinopathy (NDR) and 61 healthy controls. Participants were tested for RAGE G82S and VEGF -634 G/C polymorphisms by polymerase chain reaction-restriction fragment length polymorphism.RESULTSWe found a significant association between VEGF -634 G/C polymorphism and PDR as PDR patients had increased incidence of VEGF -634 CC genotype compared to NDR patients [odds ratio for CC vs (GC+GG)=6.5, 95% CI=1.5-27.8, P=0.021]. Also VEGF -634 CC genotype and C allele were significantly higher in the PDR than in NPDR patients, which is a novel finding in our study (P=0.024, 0.009 respectively). The mean triglycerides level was significantly higher in diabetic patients with CC genotype (P=0.01) as compared to patients with other genotypes. All cases and control subjects were of the same heterozygous RAGE 82G/S genotype.CONCLUSIONPatients carrying VEGF -634 C polymorphism have a higher risk of PDR development, so VEGF -634 G/C polymorphism could be used as a predictive marker for PDR in diabetic patients. We could not find a significant association between RAGE G82S polymorphism and DR.

Functions of Müller cell-derived vascular endothelial growth factor in diabetic retinopathy

Müller cells are macroglia and play many essential roles as supporting cells in the retina.To respond to pathological changes in diabetic retinopathy(DR),a major complication in the eye of diabetic patients,retinal Müller glia produce a high level of vascular endothelial growth factor(VEGF or VEGF-A).As VEGF is expressed by multiple retinal cell-types and Müller glia comprise only a small portion of cells in the retina,it has been a great challenge to reveal the function of VEGF or other globally expressed proteins produced by Müller cells.With the development of conditional gene targeting tools,it is now possible to dissect the function of Müller cell-derived VEGF in vivo.By using conditional gene targeting approach,we demonstrate that Müller glia are a major source of retinal VEGF in diabetic mice and Müller cell-derived VEGF plays a significant role in the alteration of protein expression and peroxynitration,which leads to retinal inflammation,neovascularization,vascular leakage,and vascular lesion,key pathological changes in DR.Therefore,Müller glia are a potential cellular target for the treatment of DR,a leading cause of blindness.

Dan Huang Ming Mu Recipe Suppresses the Progression of Streptozotocin-induced Diabetic Retinopathy After Retinal Laser Photocoagulation in Brown Norway Rats via Down-regulating Vascular Endothelial Growth Factor and Up-regulating Pigment Epithelium-derived

Objective To analyze the effects of Dan Huang Ming Mu Recipe(DHMMR)(a pharmaceutical preparation from herbs and having the function of replenishing vital essence,removing heat,promoting blood circulation and excreting pathogenic water) on diabetic retinopathy(DR) after retinal laser photocoagulation through regulating the expression of vascular endothelial growth factor(VEGF) and pigment epithelium-derived factor(PEDF).Methods Forty male Brown Norway(BN) rats were randomly divided into blank group(group A,10 BN rats) and model group(30 BN rats).DR models were induced by 40 mg/kg streptozotocin(STZ) and the body weight and blood glucose of rats were monitored.After 12-week injection,fluorescein fundus angiography(FFA) and histopathological examination were detected to confirm the successful establishment of DR models.Subsequently,the right eyes of model group rats were conducted retinal laser photocoagulation with the left eyes having no retinal laser photocoagulation and rats of the model group were randomly divided into group B(the model control group),group C(the positive control group),and group D(the DHMMR group),with 10 rats in each group.Rats of the group A and the group B were given vehicle,and the group C were given calcium dobesilate suspension by gavage,and the group D were given DHMMR by gavage.After 4-week gavage,FFA was carried out to observe the fundus microvascular change.Then,the rats were sacrificed to do histopathological examinations and the serum levels of P-selectin,cAMP,cGMP,and the relative expression of the protein of VEGF and PEDF in retina were detected.Results After 12-week STZ injection,the blood glucose of the model group were pronouncedly higher than the blank group(P < 0.01).Fundus micro-hemangioma changes were observed in the rats of the model group through FFA,and the rats of the blank group did not see any changes.The pictures of HE staining showed that the retinal structure of the model group was more disordered than the blank group.After 4-week gavage,treatments with DHMMR showed dramatic reduction of serum levels of Pselectin,cAMP and cGMP compared with the group B(P < 0.01).FFA and histopathological examinations of DHMMR-treated rats revealed significantly suppression of retinal edema,fundus microvascular destruction and retinal destruction distinguishing from the group B.And the relative expression of VEGF protein of the group D and the group A was markedly lower than that of the group B(P < 0.01).The relative expression of PEDF protein of the group D and the group A was dramatically higher than that of the group B to the contrary(P < 0.01).Conclusions DHMMR demonstrates pronounced suppressive effects on the progression of DR after retinal laser photocoagulation,through down-regulating VEGF and upregulating PEDF.

IL-4, IL-6, IL-10, IL-17A and vascular endothelial growth factor in the vitreous of patients with proliferative diabetic retinopathy

In current article, results of the determination of the concentrations of vascular endothelial growth factor (VEGF), and some interleukins (IL-4, IL-6, IL-10, IL-17А) in the vitreous of patients with proliferative diabetic retinopathy are presented. We have found that in the mechanism of development of diabetic retinopathy, significant role plays an activation of local inflammation process and vascular proliferation. This is evidenced by a significant increase in the vitreous concentration of IL-4, IL-6, IL-10, IL-17A and vascular endothelial growth factor. Identified correlations between VEGF and IL-17A, between VEGF and IL-4, and between IL-17A and IL-4 show the relationship of inflammation and proliferation processes in the pathogenesis of diabetic retinopathy.

Diabetic macular edema:Efficacy and safety of antivascular endothelial growth factor therapy

Diabetic retinopathy is one of the prominent causes of vision impairment in the working-age population in industrialized countries and is related to 1%-5% of cases of blindness in the world. Among patients with diabetic retinopathy, diabetic macular edema(DME) is the major reason of vision impairment and represents a significant public health problem. Previous studies demonstrated the role of vascular endothelial growth factor(VEGF) in diabetic retinopathy and DME pathogenesis, and also revealed the efficacy of anti-VEGF agents for the management of these disorders. This review summarizes the outcomes of clinical studies that evaluated the anti-VEGF therapy including pegaptanib, ranibizumab, bevacizumab, and aflibercept for the management of DME. A significant number of clinical trials indicated favorable functional and anatomical results of anti-VEGF therapy for DME. Therefore, these agents should be considered an option in the treatment of DME in routine clinical practice.

Elevated Vascular Endothelial Growth Factor Levels in the Vitreous of Patients With Proliferative Diabetic Retinopathy

Objective: To detect the levels of vascular endothelial growth factor (VEGF) in the vitreous of patients with proliferative diabetic retinopathy (PDR) and to investigate the possible role of VEGF in the development of neovascularization in PDR. Methods ; Undiluted vitreous samples and fasting venous blood samples were obtained from 27 patients with PDR and 14 subjects with idiopathic macular hole who underwent pars plana vitrectomy. The concentration of VEGF was determined by quantitative enzyme - linked immunosorbent assay (ELISA).Results: The level of vitreous VEGF in patients with PDR (median 0. 41ng/ml, range 0. 09- 11. 56ng/ml) was significantly elevated when compared with that in control subjects (median 0.017ng/ml, range 0.008-0.04ng/ml)(P<0. 001). The median of PDR patients' serum VEGF concentration was 0.19ng/ml (0. 090. 46ng/ ml) which was far lower than vitreous VEGF concentration (P<0. 05). Vitreous VEGF concentration was higher in PDR patients with retinal detachment than that in patient

Three-dimensional-arterial spin labeling perfusion correlation with diabetes-associated cognitive dysfunction and vascular endothelial growth factor in type 2 diabetes mellitus rat

BACKGROUND Type 2 diabetes mellitus(T2DM) has been strongly associated with an increased risk of developing cognitive dysfunction and dementia.The mechanisms of diabetes-associated cognitive dysfunction(DACD) have not been fully elucidated to date.Some studies proved lower cerebral blood flow(CBF) in the hippocampus was associated with poor executive function and memory in T2DM.Increasing evidence showed that diabetes leads to abnormal vascular endothelial growth factor(VEGF) expression and CBF changes in humans and animal models.In this study,we hypothesized that DACD was correlated with CBF alteration as measured by three-dimensional(3D) arterial spin labeling(3D-ASL) and VEGF expression in the hippocampus.AIM To assess the correlation between CBF(measured by 3D-ASL and VEGF expression) and DACD in a rat model of T2DM.METHODS Forty Sprague-Dawley male rats were divided into control and T2DM groups.The T2DM group was established by feeding rats a high-fat diet and glucose to induce impaired glucose tolerance and then injecting them with streptozotocin to induce T2DM.Cognitive function was assessed using the Morris water maze experiment.The CBF changes were measured by 3D-ASL magnetic resonance imaging.VEGF expression was determined using immunofluorescence.RESULTS The escape latency time significantly reduced 15 wk after streptozotocin injection in the T2DM group.The total distance traveled was longer in the T2DM group;also,the platform was crossed fewer times.The percentage of distance in the target zone significantly decreased.CBF decreased in the bilateral hippocampus in the T2DM group.No difference was found between the right CBF value and the left CBF value in the T2DM group.The VEGF expression level in the hippocampus was lower in the T2DM group and correlated with the CBF value.The escape latency negatively correlated with the CBF value.The number of rats crossing the platform positively correlated with the CBF value.CONCLUSION Low CBF in the hippocampus and decreased VEGF expression might be crucial in DACD.CBF measured by 3D-ASL might serve as a noninvasive imaging biomarker for cognitive impairment associated with T2DM.

The Study on the Relationship between Serum Vascular Endothelial Growth Factor and Proteinuria in Adriamycin induced Nephrotic Rats

To study the relationship between serum vascular endothelial growth factor (VEGF) and proteinuria in adriamycin induced nephrotic rats, a rat model of adriamycin induced nephrotitis was developed by injection of adriamycin into a tail vein in a rat. At different time points, 24 h urinary protein excretion was measured by using Coomassie brilliant blue method and the serum VEGF levels detected by using ELISA assay. The interventional effect of VEGF on this model was observed. The results showed that: (1) The adriamycin induced nephrotic syndrome rat model was developed successfully; (2) Serum VEGF levels and proteinuria were significantly increased at 7th day after intravenous injection of adriamycin. There was a positive correlation between serum VEGF levels and 24 h urinary protein excretion ( r=0.67, P <0.05). (3) The 24 h urinary protein excretion was significantly increased in the rats receiving administration of VEGF ( P <0.05). It was concluded that VEGF might play an important role in the pathogenesis of proteinuria in adriamycin induced nephrotic rats.

Evaluation of Serum and Aqueous Humor Vascular Endothelial Growth Factor in Neovascular Glaucoma

Purpose: The study aimed to evaluate and correlate between the levels of vascular endothelial growth factor (VEGF) in serum and aqueous humor in cases of neovascular glaucoma (NVG) to stand up on if it can be used as a marker for early detection of such cases. Methods: This observational case control study included 60 eyes, divided into 3 groups, group A of 30 eyes presented by cataract of different causes (not diabetic patients and no signs of NVG) as a control group and group B of 30 eyes with NVG due to different causes, group C of the same eyes in group B but after one month of treatment by intravitreal bevacizumab and laser treatment by pan retinal photocoagulation (PRP). Serum VEGF was estimated in all groups, also aqueous humor VEGF was estimated in group A and B only. In addition glycosylated hemoglobin (HbA1c) was estimated in group B;statistical analysis of the results was performed. Results: The study revealed that the commonest cause of NVG was proliferative diabetic retinopathy (PDR) in 26 cases (86.7%), HbA1c in group B revealed mean value 7.68% ± 2.75%. Serum VEFG level in the group B of cases of NVG was significantly higher than the control group A (P 0.05). Conclusions: VEGF is considered a good marker for the NVG either in serum or aqueous humor, laser treatment and the use of anti-VEGF are crucial treatment for such cases, and also glycemic control is a must for regulation of the vascular process in diabetic patients for prevention of such ocular neovascularization.

Vascular endothelial growth factor B inhibits insulin secretion in MIN6 cells and reduces Ca2+ and cyclic adenosine monophosphate levels through PI3K/AKT pathway

BACKGROUND Type 2 diabetes(T2 D) is characterized by insufficient insulin secretion caused by defective pancreatic β-cell function or insulin resistance,resulting in an increase in blood glucose.However,the mechanism involved in this lack of insulin secretion is unclear.The level of vascular endothelial growth factor B(VEGF-B) is significantly increased in T2 D patients.The inactivation of VEGF-B could restore insulin sensitivity in db/db mice by reducing fatty acid accumulation.It is speculated that VEGF-B is related to pancreatic β-cell dysfunction and is an important factor affecting β-cell secretion of insulin.As an in vitro model of normal pancreatic β-cells,the MIN6 cell line can be used to analyze the mechanism of insulin secretion and related biological effects.AIM To study the role of VEGF-B in the insulin secretion signaling pathway in MIN6 cells and explore the effect of VEGF-B on blood glucose regulation.METHODS The MIN6 mouse pancreatic islet β-cell line was used as the model system.By administering exogenous VEGF-B protein or knocking down VEGF-B expression in MIN6 cells,we examined the effects of VEGF-B on insulin secretion,Ca2+ and cyclic adenosine monophosphate(cAMP) levels,and the insulin secretion signaling pathway.RESULTS Exogenous VEGF-B inhibited the secretion of insulin and simultaneously reduced the levels of Ca2+ and cAMP in MIN6 cells.Exogenous VEGF-B also reduced the expression of phospholipase C gamma 1(PLCγ1),phosphatidylinositol 3-kinase(PI3 K),serine/threonine kinase(AKT),and other proteins in the insulin secretion pathway.Upon knockdown of VEGF-B,MIN6 cells exhibited increased insulin secretion and Ca2+ and cAMP levels and upregulated expression of PLCγ1,PI3 K,AKT,and other proteins.CONCLUSION VEGF-B can regulate insulin secretion by modulating the levels of Ca2+ and cAMP.VEGF-B involvement in insulin secretion is related to the expression of PLCγ1,PI3 K,AKT,and other signaling proteins.These results provide theoretical support and an experimental basis for the study of VEGF-B in the pathogenesis of T2 D.

Bilateral same-session intravitreal injections of antivascular endothelial growth factors

AIMTo document the indications, safety and possible complications of bilateral same-session intravitreal anti-vascular endothelial growth factor (VEGF) injections performed in the ophthalmic operating room.

Research progress on the role of connective tissue growth factor in fibrosis of diabetic retinopathy

Diabetic retinopathy（DR） is one of the most important types of diabetic microangiopathy, which is a specific change of fundus lesions and is one of the most serious complications of diabetes. When DR develops to proliferative DR, the main factors of decreasing vision, and even blindness, include retinal detachment and vitreous hemorrhage caused by contraction of blood vessels by fiber membrane. Recent studies reported that the formation of fiber vascular membrane is closely related to retinal fibrosis. The connective tissue growth factor（CTGF） is a cytokine that is closely related to DR fibrosis. However, its mechanism is poorly understood. This paper summarizes the recent studies about CTGF on DR fibrosis for a comprehensive understanding of the role and mechanism of CTGF in PDR.