Plasma Vascular Endothelial Growth Factor Concentrations Research Articles

Association of Angiotensinogen Gene Polymorphisms and Angiogenic Factors with Preeclampsia in Chinese Women

Objective: To investigate the association of angiotensinogen (AGT) gene polymorphisms and angiogenic factors with preeclampsia (PE) in Chinese women. Methods: A study on Chinese women was performed. Detection of the M235T polymorphism of AGT gene was carried out by PCR. Using a χ² test, genotype and allele frequencies were compared in all groups. Maternal serum levels of vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) and soluble fms-like tyrosine kinase 1 (sFlt1) at gestation were compared between 92 women with PE and 100 controls by ELISA. Results: Compared to the controls, the AGT homozygous of TT genotype in PE occurred significantly more frequently and the T allele was observed to occur more frequently than the M allele (p < 0.05). sFlt1 was present in high quantities in the serum of women with PE and was associated with low levels of free VEGF and PlGF (p < 0.05). Plasma sFlt1 levels are higher in PE patients with TT heterozygotes compared with MM homozygotes, but PIGF is lower (p < 0.05). Plasma VEGF concentrations showed no significant difference. Conclusions: Our study showed that AGT M235T polymorphism is associated with PE in Chinese women. Furthermore, the gene polymorphism of the components of the renin-angiotensin system may contribute to the concentration alterations of sFlt1, VEGF, and PlGF in maternal serum, which causes disordered vasculogenesis contributing to PE.

Evaluation of selected angiogenic and inflammatory markers in endometriosis before and after danazol treatment

Angiogenesis and inflammation are pivotal processes in developing endometriosis in the peritoneal cavity. The aim of the present study was to evaluate these two processes in women with endometriosis who had been treated with danazol to determine the sensitivity of a non-invasive test in diagnosing endometriosis. The clinical follow-up study was conducted in a group of 103 women diagnosed laparoscopically with endometriosis. Thirty-five patients qualified for danazol treatment. Pain was assessed using a visual analogue scale, whereas endometriosis was assessed using the revised American Society of Reproductive Medicine (rASRM) scale. Cancer antigen (CA)-125 and C-reactive protein (CRP) concentrations in plasma and peritoneal fluid were determined by immunoenzymatic methods, whereas vascular endothelial growth factor (VEGF) and interleukin (IL)-1β concentrations in plasma and peritoneal fluid were determined by ELISA. Endometrial expression of IL-8 and platelet-derived growth factor alpha polypeptide (PDGF-A) was determined using real-time polymerase chain reaction (PCR). Women with endometriosis (68.9% of patients) had higher plasma concentrations of CA-125, as well as higher concentrations of both CA-125 and VEGF in the peritoneal fluid. Endometrial expression of IL-8 mRNA was significantly higher, whereas that of PDGF-A was significantly lower, in contrast. After danazol treatment the patients reported lower pain scores; in addition, CA-125 concentrations in the plasma were decreased (P<0.001), whereas VEGF concentration in the plasma increased (P=0.009). For the diagnosis of endometriosis, none of the combinations of given markers had a sensitivity >60%. Danazol treatment is highly effective in relieving pain and decreasing CA-125 concentrations in the plasma. Higher plasma concentrations of VEGF after treatment could imply stimulation of angiogenesis.

Distribution of Selenium and Oxidative Stress in Breast Tumor-Bearing Mice

The present study investigated the effects of breast tumors on the blood and tissue distribution of essential trace mineral selenium (Se), and oxidative stress status of mice. Female 10-week-old BALB/cByJNarl mice were randomly assigned into control (CNL) and breast tumor-bearing (TB) groups. TB mice were injected subcutaneously into the right hind thigh with 5 × 106 EMT6 mouse mammary tumor cells. After 22 days, we measured Se concentrations, Se-dependent glutathione peroxidase (GPx) activities, and malondialdehyde (MDA) products (indicator of oxidative stress) in plasma, various tissues, and plasma vascular endothelial growth factor (VEGF) concentrations. There were no significant differences in body weights and daily intake between both groups. Compared with the CNL group, TB mice have decreases in plasma Se concentrations and GPx activities, as well as higher plasma VEGF and MDA concentrations. Plasma Se concentrations were also negatively correlated with plasma MDA and VEGF concentrations. Furthermore, tissue Se concentrations and GPx activities in TB animals were lower; whereas the MDA concentrations higher in various tissues including liver, kidney, brain, lung, spleen, and thymic tissues. In conclusion, disruption of Se homeostasis critically reflects oxidative stress in target tissues, thus may increase the risk for progression of breast cancer and metastasis.

Concentration of vascular endothelial growth factor in patients with acute coronary syndrome

Vascular endothelial growth factor (VEGF) is a regulator of vascular formation in physiological and pathological conditions. The aim of our study was to evaluate the value of VEGF as a surrogate marker of myocardial injury in acute ischemic conditions. Materials and methodsIn 104 consecutive patients with acute coronary syndrome (ACS) with and without ST segment elevation (STEMI and NSTEMI) the plasma and serum human VEGF (hVEGF) concentration was measured two times i.e. immediately after admission due to ACS and 24h later. According to ECG findings and coronary angiography results, patients were divided into three groups. Group A represented major myocardial injury due to ST-segment elevation in precordial leads and/or in I and aVL leads and with left anterior descending (LAD) artery responsible for STEMI symptoms or additionally with significant atherosclerotic lesions (lumen vessel narrowed>50%) in other than LAD coronary arteries. Group B (medium myocardial injury) consisted of patients with ST-segment elevation in II, III and aVF leads and/or ST-segment depression in V2-V3 leads with one-vessel disease and the culprit artery was not LAD. Group C included patients with changes in ECG other than ST-segment elevation independently of the site of atherosclerotic lesions in coronary arteries. ResultsIn all 104 patients with ACS the highest values of serum hVEGF were observed in second measurement (357.9±346 pg/ml, p<0.01). Although in the first measurement, plasma and serum hVEGF concentration did not differentiate groups, the difference between deltas for serum hVEGF was observed (p<0.05). Increased number of neutrophils in the first measurement increased the OR of the high serum hVEGF concentration in the first measurement (OR=1.155; 95%CI: 1.011; 1.32) (p<0.05). The number of neutrophils in the second measurement also revealed significant relationship with high serum hVEGF in the first assessment (OR=1.318, 95%CI: 1.097; 1.583) (p<0.01). Increased values of triglycerides (exceeding the upper limit) were connected with decreased OR of high serum hVEGF concentrations in the first measurement (OR=0.152, 95%CI: 0.033; 0.695, p<0.05). ConclusionsIn acute coronary syndrome, serum VEGF concentrations are elevated and can serve as a surrogate marker of myocardial injury. The elevated number of neutrophils increases odds ratio of high VEGF concentrations in ACS. In patients with high concentrations of triglycerides, odds ratio of low level of hVEGF is expected.

Compartment Model Predicts VEGF Secretion and Investigates the Effects of VEGF Trap in Tumor-Bearing Mice

Angiogenesis, the formation of new blood vessels from existing vasculature, is important in tumor growth and metastasis. A key regulator of angiogenesis is vascular endothelial growth factor (VEGF), which has been targeted in numerous anti-angiogenic therapies aimed at inhibiting tumor angiogenesis. Systems biology approaches, including computational modeling, are useful for understanding this complex biological process and can aid in the development of novel and effective therapeutics that target the VEGF family of proteins and receptors. We have developed a computational model of VEGF transport and kinetics in the tumor-bearing mouse, which includes three-compartments: normal tissue, blood, and tumor. The model simulates human tumor xenografts and includes human (VEGF121 and VEGF165) and mouse (VEGF120 and VEGF164) isoforms. The model incorporates molecular interactions between these VEGF isoforms and receptors (VEGFR1 and VEGFR2), as well as co-receptors (NRP1 and NRP2). We also include important soluble factors: soluble VEGFR1 (sFlt-1) and α-2-macroglobulin. The model accounts for transport via macromolecular transendothelial permeability, lymphatic flow, and plasma clearance. We have fit the model to available in vivo experimental data on the plasma concentration of free VEGF Trap and VEGF Trap bound to mouse and human VEGF in order to estimate the rates at which parenchymal cells (myocytes and tumor cells) and endothelial cells secrete VEGF. Interestingly, the predicted tumor VEGF secretion rates are significantly lower (0.007–0.023 molecules/cell/s, depending on the tumor microenvironment) than most reported in vitro measurements (0.03–2.65 molecules/cell/s). The optimized model is used to investigate the interstitial and plasma VEGF concentrations and the effect of the VEGF-neutralizing agent, VEGF Trap (aflibercept). This work complements experimental studies performed in mice and provides a framework with which to examine the effects of anti-VEGF agents, aiding in the optimization of such anti-angiogenic therapeutics as well as analysis of clinical data. The model predictions also have implications for biomarker discovery with anti-angiogenic therapies.

Associations between Vascular Endothelial Growth Factor Gene Polymorphisms and Susceptibility to Acute Mountain Sickness

This study investigated associations between polymorphisms in the vascular endothelial growth factor (VEGF) gene and susceptibility to acute mountain sickness. Two hundred Han Chinese soldiers who developed acute mountain sickness after rapidly ascending to an altitude of < 3600 m and 200 control soldiers (who did not develop the condition) were enrolled in the study. Twelve single nucleotide polymorphisms (SNPs) of the VEGF gene were genotyped in all the study participants. Plasma VEGF concentrations were measured by enzyme-linked immunosorbent assay in 40 subjects with acute mountain sickness and 40 controls before and after exposure to high altitude. The frequencies of the rs3025039 genotype and allele were significantly different between the groups. Two SNPs, rs3025039 (which involves a C→T allele variation at position 936 in the 3' untranslated region) and rs3025030 (which involves a G→C allele variation in the intronic sequence), were associated with a decreased risk of acute mountain sickness. The SNPs rs3025039 and rs3025030 of the VEGF gene may be associated with a decreased risk of acute mountain sickness development.

Sputum VEGF level increases with treatment of COPD acute exacerbation

Introduction: The role of vascular endothelial growth factor (VEGF) in COPD pathogenesis has been studied widely; however the change in blood and airway VEGF levels during the treatment of an acute exacerbation has not been investigated. In this study we aimed to evaluate the changes in plasma and sputum VEGF levels during COPD exacerbation. Methods: 14 subjects (64±10 years) with established COPD participated in the study. Spontaneous sputa and EDTA-plasma samples were collected for VEGF measurement at admission to hospital due to an acute exacerbation of COPD (Anthonisen type I-II) and also at discharge from hospital. During hospitalization (8±1 days) patients were treated with systemic corticosteroids (n=12) and/or with antibiotics (n=7). VEGF concentration was measured by ELISA. Data are shown as mean±SD and analyzed with parametric tests. Results: Sputum VEGF levels positively correlated with FEV1 percent predicted (r=0.61, p=0.02) and FEV1/FVC (r=0.55, p=0.04) at baseline, while no relationship was observed between plasma VEGF level and clinical parameters. There was no correlation between sputum and plasma VEGF concentrations (p=0.65). Sputum level of VEGF increased significantly (6670±6252 pg/ml vs. 9735±6909 pg/ml, before vs. after treatment, p=0.04) following treatment, while there was no change in plasma VEGF levels (179±98 pg/ml vs. 173±93 pg/ml, before vs. after treatment p=0.73). Conclusion: Recovery from COPD exacerbation might be associated with increased airway VEGF level. Analysis of sputum but not plasma may reflect the changes in VEGF levels in COPD patients during exacerbation. The study was supported by National Scientific Research Fund (OTKA 68808) and Hungarian Respiratory Society grants.

Analysis of the expression levels of survivin and VEGF in patients with acute lymphoblastic leukemia

The purpose of this study was to investigate the association between an inhibitor of apoptosis (survivin) and vascular endothelial growth factor (VEGF) expression in patients with acute lymphoblastic leukemia (ALL) prior to and following chemotherapy. Reverse transcription (RT)-PCR and western blotting were employed to analyze survivin and VEGF mRNA and protein expression. Moreover, the concentrations of survivin and VEGF were determined by enzyme-linked immunosorbent assay (ELISA). Our data revealed that survivin and VEGF were overexpressed in patients with ALL prior to treatment, while survivin levels were significantly decreased following treatment. In addition, there was a positive correlation between survivin and VEGF concentrations in plasma. In conclusion, analysis of survivin and VEGF expression levels may improve the clinical diagnosis and treatment of ALL.

Quantification of Plasma and Bone Marrow VEGF and Angiopoietin-2 Levels in Pediatric Malignancies

Data on angiogenesis in pediatric patients with malignancy are scarce. Our aim was to study angiogenic growth factors vascular endothelial growth factor (VEGF) and angiopoietin-2 (Ang2) in pediatric oncological patients at diagnosis and a few months after the beginning of the therapy. Eighty-four consecutive patients with malignancy were included in this study. The levels of plasma and bone marrow VEGF and Ang2 were analyzed by enzyme-linked immunosorbent assay. The levels of VEGF were higher in patients with solid tumors than in patients with leukemias (P=0.003), whereas Ang2 concentrations showed the opposite (P=0.003). Interestingly, the plasma concentrations of both VEGF and Ang2 correlated with concentrations in the bone marrow (P<0.05). Leukemia patients with lower VEGF level and patients with higher Ang2 level at follow-up had longer event-free survival than other patients (P=0.032 and 0.053, respectively). The results of our study enlighten the behavior of 2 different angiogenic factors in pediatric patients with malignancy. An interesting finding was the connection between survival of pediatric leukemia patients and angiogenic factor levels a few months after the beginning of therapy. Pathophysiology and clinical applications of these findings need further studies.

Increased plasma concentration of vascular endothelial growth factor in patients with atopic dermatitis and its relation to disease severity and platelet activation

BackgroundOverproduction of vascular endothelial growth factor (VEGF) in atopic dermatitis (AD) lesions has previously been observed. It is also known that platelet is an important source of VEGF and platelet factor 4 (PF-4), a potential marker of AD severity.AimTo evaluate concentrations of VEGF and its soluble receptors (sVEGF-R1 and sVEGF-R2) in the plasma of AD patients and to examine its possible correlation with disease severity and plasma concentrations of PF-4, a platelet activation marker.MethodsPlasma concentrations of VEGF and its receptors and levels of PF-4 were measured by an immunoenzymatic assay in 51 AD patients and in 35 healthy non-atopic controls. The severity of the disease was evaluated using the eczema area and severity index.ResultsAD patients showed significantly increased VEGF and PF-4 plasma concentrations as compared with the controls. Plasma concentrations of sVEGF-R1 and sVEGF-R2 did not differ between the groups. There were no remarkable correlations between plasma VEGF concentration and disease severity or between VEGF and PF-4 concentration.ConclusionsThis study shows that plasma concentration of VEGF may be increased in patients suffering from AD. It seems that plasma VEGF concentration is not a useful marker of disease severity and, apart from platelets, other cells might also release the cytokine.

A Study of High-Altitude Hypoxia-Induced Cell Stress in Murine Model

We evaluated the effects of high-altitude hypoxic stress in the murine model. For this purpose, 36 CR-mice in group A were maintained at the altitude of 3,820 m for hypoxia-induced factor (HIF)-1α expression analysis by immunohistochemistry. The 36 Wistar rats in group B were maintained in low-pressure (400-420 kPa) oxygen chamber, and the effects of hypoxia on myocardial mitochondria were studied. In the 36 CR-mice of group C, plasma vascular endothelial growth factor (VEGF) levels were determined using strept-avidin-biotin complex/diaminobenzidine method after exposure to different altitudes/O(2)-concentrations. The data show that in experimental group A1, endothelin (ET)-1α concentrations gradually increased whereas HIF-1α expression in myocardial cells was higher (P < 0.01) than in control group A2. In rats of group B, the myocardial mitochondria numbers were reduced during the initial phase of acute stress response to hypoxia and cellular injury but, later, mitochondrial numbers were restored to normal values. In mice of experimental group C1, plasma VEGF concentrations increased under hypoxia, which were significantly higher (P < 0.01) than those of control group C2. We, therefore, concluded that high-altitude hypoxia: (i) induced HIF-1α expression; (ii) prompted adaptation/acclimatization after initial stress and cellular injury; and (iii) enhanced VEGF expression in murine.

Imbalanced levels of angiogenic and angiostatic factors in vitreous, plasma and postmortem retinal tissue of patients with proliferative diabetic retinopathy

A role for vascular endothelial growth factor (VEGF) has been clearly implicated in the pathogenesis of proliferative diabetic retinopathy (PDR). However, other molecules and mechanisms may be operating independently, or in conjunction with VEGF in the pathogenesis of this disease. Therefore, we made an attempt to comparatively investigate the levels of angiogenic and angiostatic factors in vitreous, plasma and postmortem retinal tissue of subjects with Proliferative Diabetic Retinopathy (PDR) compared to control subjects. The vitreous and plasma concentrations of VEGF, EPO (Erythropoietin) and PEDF (Pigment Epithelium Derived Factor) were measured using Enzyme Linked Immunosorbent Assay (ELISA) and the postmortem retinal tissue was subjected to Western blot analysis. The mean vitreous and plasma levels of VEGF and EPO in patients with PDR were significantly (p<0.001) higher than those in subjects without diabetes. Conversely, the vitreous and plasma levels of PEDF were significantly (p<0.001) lower in the PDR patients compared to control subjects. Multivariate logistic-regression analyses indicated that EPO was more strongly associated with PDR than VEGF. The protein expression of the VEGF and EPO in the retinal tissue was significantly higher in PDR and diabetes without complication groups compared to controls. Compared to controls, the protein expression of PEDF was significantly lower in retinal tissues from diabetes patients without complications and in patients with PDR. The fact that the vitreous and plasma levels and the retinal tissue protein expression of EPO were strongly associated with PDR implies a definite role of ‘hypererythropoietinemia' in neovascularization processes.

Effect of standard tuberculosis treatment on plasma cytokine levels in patients with active pulmonary tuberculosis.

BackgroundSputum Mycobacterium tuberculosis (Mtb) culture is commonly used to assess response to antibiotic treatment in individuals with pulmonary tuberculosis (TB). Such techniques are constrained by the slow growth rate of Mtb, and more sensitive methods to monitor Mtb clearance are needed. The goal of this study was to evaluate changes in plasma cytokines in patients undergoing treatment for TB as a means of identifying candidate host markers associated with microbiologic response to therapy.MethodsTwenty-four plasma cytokines/chemokines were measured in 42 individuals diagnosed with active pulmonary TB, 52% were HIV co-infected. Individuals, undergoing a 26-week standard TB treatment, were followed longitudinally over 18 months and measurements were associated with HIV status and rates of sputum culture conversion.ResultsPlasma concentrations of interferon-inducible protein-10 (IP-10) and vascular endothelial growth factor (VEGF) were significantly reduced upon TB treatment, regardless of HIV status. By the end of treatment, IP-10 concentrations were significantly lower in HIV negative individuals when compared to HIV-positive individuals (p = 0.02). Moreover, in HIV negative patients, plasma VEGF concentrations, measured as early as 2-weeks post TB treatment initiation, positively correlated with the time of sputum conversion (p = 0.0017). No significant changes were observed in other studied immune mediators.ConclusionsThese data suggest that VEGF plasma concentration, measured during early TB treatment, could represent a surrogate marker to monitor sputum culture conversion in HIV uninfected individuals.

Evaluation of Plasma and Tissue S100A4 Protein and mRNA Levels as Potential Markers of Metastasis and Prognosis in Clear Cell Renal Cell Carcinoma

To investigate levels of S100A4 protein in plasma and S100A4 mRNA in tumours from patients with clear cell renal cell carcinoma (CCRCC), and correlate these with metastasis, survival and levels of vascular endothelial growth factor (VEGF). Plasma S100A4 and VEGF protein concentrations were measured using enzyme-linked immuno sorbent assays in 39 healthy subjects and 68 consecutive patients with untreated CCRCC. Levels of S100A4 and VEGF mRNA in tumour and matched control (healthy) tissue samples were measured using realtime quantitative reverse transcription- polymerase chain reaction. Findings were analysed with respect to clinico pathological characteristics. Plasma VEGF concentrations were higher in patients with CCRCC than in healthy subjects. S100A4 and VEGF mRNA levels were up-regulated in CCRCC tumour tissue compared with control tissue samples. Logistic regression analysis revealed that up-regulated tumour S100A4 and VEGF mRNA levels were independent risk factors for the presence of invasion and/or metastasis. S100A4 and VEGF are associated with tumour invasion and metastasis, and may be useful prognostic markers in patients with CCRCC. S100A4 and VEGF may represent potential targets for therapeutic intervention.

Decreased vascular endothelial growth factor response to acute hypoglycemia in type 2 diabetic patients with hypoglycemic coma

IntroductionPlasma vascular endothelial growth factor (VEGF) was shown to increase during acute hypoglycemia and could mediate rapid adaptation of the brain. In this study we examined the neuroendocrine response in patients with type 2 diabetes mellitus (T2DM) in hypoglycemic coma or with acute neuroglycopenic symptoms. MethodsWe prospectively studied 135 consecutive T2DM patients admitted for severe hypoglycemia during a 2-year period. We collected clinical variables and measured plasma concentrations of VEGF, epinephrine, norepinephrine, cortisol and growth hormone at admission and 30min afterwards. ResultsThirty two patients developed hypoglycemic coma and 103 did not lose consciousness. Median plasma VEGF level of coma patients was 3.1-fold lower at baseline than that of non-coma patients, and even 5.3-fold lower 30min afterwards. Plasma epinephrine concentration was significantly lower just at baseline in coma patients. On the contrary, there were no differences in concentrations of the other hormones. Multivariate logistic regression analysis showed that VEGF concentration (OR 0.68; CI 0.51–0.95) was a protective factor against the development of coma. ConclusionsVEGF and epinephrine responses to acute hypoglycemia are reduced in T2DM patients who develop hypoglycemic coma. An increased plasma VEGF concentration appeared to be a protective factor against the development of hypoglycemic coma.

Effects of exercise of different intensities on the angiogenesis, infarct healing, and function of the left ventricle in postmyocardial infarction rats

Lifestyle interventions, including physical exercise, are feasible options for the prevention and treatment of cardiovascular diseases. In this study, the effects of exercise of different intensities on the infarct region, function, and angiogenesis of the left ventricle (LV) in postmyocardial infarction (MI) rats were investigated and the levels of vascular endothelial growth factor (VEGF) proteins in the LV and plasma were examined. Male Sprague-Dawley rats were randomly assigned to six groups. The exercise-trained rats observed a daily 60-min treadmill routine 5 days/weeks for 6 weeks. Different treadmill speeds were used in the high-intensity exercise (HIE), moderate-intensity exercise (MIE), and low-intensity exercise (LIE) groups, whereas the untrained rats remained sedentary (Sed). At 6 weeks, all rats underwent either an acute MI operation or a sham (Sh) MI operation 24 h after their last treadmill exercise or the corresponding Sed protocol. They were then killed 7 days after recovery. Echocardiographic and hemodynamic measurements were taken at the end of the experimental protocol. The infarct regions were analyzed using Masson's trichrome staining, whereas intramyocardial microvessels were detected using Factor VIII-related antigen staining. The cardiac VEGF protein levels were determined by western blotting analysis, and plasma VEGF concentrations were examined by enzyme-linked immunosorbent assay. Compared with the corresponding parameters in the Sed-Sh group, LV function did not significantly ameliorate and microvessel density did not increase in the MIE-Sh group. Compared with the Sed-MI group, the MIE-MI and HIE-MI groups had significantly reduced LV infarct size, improved hemodynamic parameters, and increased fractional shortening, scar thickness, and microvessel density, these parameters did not significantly change in the LIE-MI group. In addition, the MIE-MI and HIE-MI rats had significant differences in hemodynamic parameters and microvessel density. Compared with those of the Sed-MI group, the heart and plasma of the exercise-trained rats in the MIE-MI and HIE-MI groups displayed higher levels of VEGF protein, but the difference between the MIE-MI and HIE-MI groups was not significant. Moderate-intensity running before acute MI improved LV function, reduced scar size, and increased scar thickness and microvessel density in post-MI rats. Exercise at a higher intensity could have further small effects. LIE may be beneficial, but it would not be sufficient to improve MI. Moderate-intensity and high-intensity running upregulated the expression of VEGF protein and increased microvessels, which may have partly improved cardiac function after MI in this study.

Vascular endothelial growth factor plasma levels before and after treatment of neovascular age‐related macular degeneration with bevacizumab or ranibizumab

To evaluate the changes of vascular endothelial growth factor (VEGF) plasma levels after intravitreal injections of ranibizumab or bevacizumab in patients with exudative age-related macular degeneration (AMD). Forty-three patients with exudative AMD and 19 age- and sex-matched control patients without chorioretinal diseases were studied. Nineteen patients were treated with intravitreal ranibizumab 0.5 mg, 24 with intravitreal bevacizumab 1.25 mg. Blood samples were collected just before the first injection, and 28 days after three initial consecutive injections performed in 4-weekly intervals (loading dose). Concentration of VEGF in the plasma was measured by ELISA. At baseline, the median VEGF concentrations in controls were 180.97 pg/ml, in the bevacizumab group 189.72 pg/ml and in the ranibizumab group 191.36 pg/ml. VEGF plasma concentrations in patients with wet AMD were comparable to controls (p = 0.225). Twenty-eight days after the third injection, a significant reduction of 42% in the median VEGF plasma levels was found in bevacizumab-treated patients (109.97 pg/ml; p = 0.0002) but not in ranibizumab-treated patients (189.97 pg/ml; p = 0.198) where a reduction of 0.7% in the median value was found. Intravitreal bevacizumab significantly reduced VEGF plasma levels until 28 days after intravitreal injection in patients with exudative AMD. Ranibizumab did not achieve a significant plasma VEGF reduction at the same time-point. These findings alert to the potential systemic safety differences between the two drugs after intravitreal administration.

Stability Analysis of Vascular Endothelial Growth Factor in Cerebrospinal Fluid

Vascular endothelial growth factor (VEGF) is a promising biological marker and prognostic indicator in many neurological diseases. Although VEGF concentrations in plasma and cerebrospinal fluid (CSF) are increasingly reported, CSF-VEGF stability pre- and during-assay procedures is seldom evaluated. In the current study, we investigated VEGF variability and stability in CSF related to sample preparation, storage, and routine experimental procedures. Results showed that contaminant cell breakdown or aggregation can occur gradually before sample processing. However, after the removal of contaminant cell components, CSF-VEGF levels did not show significant changes in samples incubated at room temperature for 5 h, thawed/refrozen for 6 cycles. Samples preserved at -80 °C for up to 7 years continued to show measurable levels. Since some cellular components such as platelets contain a large amount of releasable VEGF, we conclude that CSF samples should be processed as soon as possible to carefully remove all cellular components and prevent possible consequent release of VEGF into CSF. After centrifugation to remove cellular contents, VEGF in CSF was relatively stable during routine experimental procedures and storage.

In vitro viability and secretory capacity of human luteinized granulosa cells after gonadotropin-releasing hormone agonist trigger of oocyte maturation

To evaluate viability of luteinized granulosa cells obtained from patients triggered with either GnRH agonist or hCG and to assess the secretion of steroids and vascular endothelial growth factor (VEGF) by cultured luteinized granulosa cells in the presence or absence of hCG. Prospective, randomized controlled trial. University-based fertility center. A subset of patients who underwent a randomized trial involving GnRH agonist trigger after GnRH antagonist protocol vs. hCG trigger after pituitary suppression with GnRH agonist protocol. In vitro fertilization cycles. Proportion of apoptosis; basal and hCG-induced secretion of E(2), P, and VEGF by luteinized granulosa cells; follicular-fluid VEGF and luteal-phase serum E(2), P, and plasma VEGF concentrations. There were no differences in the proportion of granulosa/luteal cell apoptosis, follicular-fluid or luteal-phase plasma VEGF concentration, or basal culture media E(2), P, and VEGF concentrations between the two groups. Addition of hCG to the culture media significantly increased the P concentration in both groups, but there were no changes in E(2) or VEGF concentrations. Serum E(2) levels were lower at 5 and 9 days after GnRH agonist compared with hCG trigger. The granulosa/luteal cells obtained on the day of oocyte retrieval after GnRH agonist trigger are still viable and have the capacity to respond to hCG by increasing the secretion of steroids.

Circulating endothelial progenitor cells in strength‐trained men

Aerobic exercise training influences the number of putative endothelial progenitor cells (EPCs), but the effects of strength training remains unclear. We examined the effects of strength training on EPCs using the cross-sectional study design. We also investigated the effects of strength training on vascular endothelial growth factor (VEGF), which is a possible mediator of EPCs. We studied 21 healthy young men (10 sedentary and 11 strength-trained). The number of EPCs that circulates peripherally was determined by the surface markers CD34+ and KDR+ using flow cytometry. Plasma concentrations of VEGF were measured by ELISA. The number of circulating EPCs was higher in the strength-trained group than in the sedentary (P < 0.05). We observed a positive correlation between the number of EPCs and plasma VEGF concentrations, although plasma VEGF concentrations did not differ between the groups. These results suggest that regular strength exercise increase the number of circulating EPCs in young men and it associated with not only VEGF but also other factors.