scholarly journals 17β-Estradiol Increases Astrocytic Vascular Endothelial Growth Factor (VEGF) in Adult Female Rat Hippocampus

Endocrinology ◽  
2011 ◽  
Vol 152 (5) ◽  
pp. 1745-1751 ◽  
Author(s):  
Sharon Barouk ◽  
Tana Hintz ◽  
Ping Li ◽  
Aine M. Duffy ◽  
Neil J. MacLusky ◽  
...  
Keyword(s):  
Vascular Endothelial Growth Factor ◽  
Growth Factor ◽  
Adult Female ◽  
Serum Levels ◽  
Female Rats ◽  
Female Rat ◽  
Vascular Endothelial ◽  
17Β Estradiol ◽  
Endothelial Growth Factor ◽  
Vegf Protein

Vascular endothelial growth factor (VEGF) is critical to angiogenesis and vascular permeability. It is also important in the endocrine system, in which VEGF mediates the vascular effects of estrogens in target tissues such as the uterus, a response attributed to an estrogen response element on the VEGF gene. Here we asked whether 17β-estradiol increases VEGF levels in the brain. We focused on the hippocampus, in which 17β-estradiol and VEGF both have important actions, and used immunocytochemistry to evaluate VEGF protein. VEGF immunoreactivity was compared in adult female rats sampled during the estrous cycle when serum levels of 17β-estradiol peak (proestrous morning) as well as when they are low (metestrous morning). In addition, adult rats were ovariectomized and compared after treatment with 17β-estradiol or vehicle. The results demonstrated that VEGF immunoreactivity was increased when serum levels of 17β-estradiol were elevated. Confocal microscopy showed that VEGF immunofluorescence was predominantly nonneuronal, often associated with astrocytes. Glial VEGF labeling was primarily punctate rather than diffuse and labile because glial VEGF immunoreactivity was greatly reduced if tissue sections were left in an aqueous medium overnight. We conclude that VEGF protein in normal female hippocampus is primarily nonneuronal rather than neuronal and suggest that glial VEGF immunoreactivity has been underestimated by past studies with other methods because there is a labile extracellular pool. We suggest that estrogens may exert actions on female hippocampal structure and function by increasing hippocampal VEGF.

scholarly journals Estrogen Receptor-α Overexpression Suppresses 17β-Estradiol-Mediated Vascular Endothelial Growth Factor Expression and Activation of Survival Kinases

Endocrinology ◽  
2008 ◽  
Vol 149 (8) ◽  
pp. 3881-3889 ◽  
Author(s):  
Shameena Bake ◽  
Lijiang Ma ◽  
Farida Sohrabji
Keyword(s):  
Vascular Endothelial Growth Factor ◽  
Estrogen Receptor ◽  
Growth Factors ◽  
Growth Factor ◽  
Cell Line ◽  
Female Rats ◽  
High Dose ◽  
Vascular Endothelial ◽  
17Β Estradiol ◽  
Endothelial Growth Factor

Estrogen and its receptors influence growth and differentiation by stimulating the production and secretion of growth factors. Our previous studies indicate an increased expression of estrogen receptor (ER)-α and decreased growth factor synthesis in the olfactory bulb of reproductive senescent female rats as compared with young animals. The present study tests the hypothesis that abnormal overexpression of ERα contributes to decreased growth factor synthesis. We developed the HeLa-Tet-On cell line stably transfected with ERα (HTERα) that expresses increasing amounts of ERα with increasing doses of doxycycline (Dox). Increasing doses of Dox had no effect on vascular endothelial growth factor (VEGF) secretion in HTERα cells. However, in the presence of 40 nm 17β-estradiol, VEGF secretion increased in low-dose Dox-exposed HTERα cultures, which was attenuated by the ERα antagonist, 1,3-Bis(4-hydroxyphenyl)-4-methyl-5-[4-(2-piperidinylethoxy)phenol]1H-pyrazole dihydrochloride. However, at high-dose Dox and, consequently, high ERα levels, estradiol failed to increase VEGF. In the HeLa X6 cell line in which the Tet-On construct is upstream of an unrelated gene (Pitx2A), estradiol failed to induce VEGF at any Dox dose. Furthermore, in the HTERα cell line, estradiol selectively down-regulates phospho-ERK2 and phospho-Akt at high ERα expression. This study clearly demonstrates that the dose of receptor critically mediates estradiol’s ability to regulate growth factors and survival kinases. The present data also support the hypothesis that 17β-estradiol treatment to an ERα overexpressing system, such as the senescent brain, could reverse the normally observed beneficial effect of estrogen.

scholarly journals Female sexual dysfunction in systemic sclerosis: The role of endothelial growth factor and endostatin

2018 ◽  
Vol 4 (1) ◽  
pp. 71-76 ◽  
Author(s):  
Antonietta Gigante ◽  
Luca Navarini ◽  
Domenico Margiotta ◽  
Biagio Barbano ◽  
Antonella Afeltra ◽  
...  
Keyword(s):  
Vascular Endothelial Growth Factor ◽  
Blood Flow ◽  
Systemic Sclerosis ◽  
Growth Factor ◽  
Sexual Dysfunction ◽  
Resistive Index ◽  
Serum Levels ◽  
Vascular Endothelial ◽  
Healthy Controls ◽  
Endothelial Growth Factor

Introduction: Since female sexual dysfunction in systemic sclerosis women is multifactorial, we can assume that vascular damage may play a role in pathogenesis. The aim of the study was to evaluate the clitoral blood flow, by Echo color Doppler, and to correlate it whit serum levels of vascular endothelial growth factor and endostatin. Methods: A total of 15 systemic sclerosis women and 10 healthy controls matched for sex and age were enrolled in this study. Serum VEGF165 and endostatin levels were determined in systemic sclerosis patients by commercial enzyme-linked immunosorbent assay kit. Clitoral blood flow was measured by Doppler indices of clitoral artery: pulsatile index, resistive index, and systolic/diastolic ratio were measured. Sexual dysfunction was assessed by Female Sexual Function Index. Results: Vascular endothelial growth factor (pg/mL) and endostatin (ng/mL) median values were significantly higher in systemic sclerosis women than healthy controls. Resistive index and systolic/diastolic ratio median values were significantly higher in systemic sclerosis women than healthy controls. Negative correlation exists between serum levels of vascular endothelial growth factor and resistive index (r = −0.55, p < 0.05). Positive correlation was observed between serum levels of endostatin and resistive index (r = 0.70, p < 0.01) and systolic/diastolic ratio (r = 0.77, p < 0.01). Discussion: We can suppose that clitoral blood flow in systemic sclerosis women is reduced not only for macro- and microvascular damage but also for impaired angiogenesis.

Effects of Hypocrellin A on Expression of Vascular Endothelial Growth Factor and Endothelin-1 in Human Umbilical Endothelial Cells

2007 ◽  
Vol 35 (04) ◽  
pp. 713-723 ◽  
Author(s):  
Lei Dang ◽  
J. Paul Seale ◽  
Xianqin Qu
Keyword(s):  
Vascular Endothelial Growth Factor ◽  
Endothelial Cells ◽  
Growth Factor ◽  
Endothelial Dysfunction ◽  
Protein Expression ◽  
Vascular Endothelial ◽  
Naturally Occurring ◽  
Hypocrellin A ◽  
Endothelial Growth Factor ◽  
Vegf Protein

Increased endothelin-1 (ET-1), vascular endothelial growth factor (VEGF) and activation of protein kinase C (PKC) are co-contributors to endothelial hyperpermeability in diabetes. Several lines of evidence have suggested a hypothesis that activation of specific PKC isoforms are the causative factor in ET-1 and VEGF mediated endothelial dysfunction. In the present study, we tested this hypothesis with hypocrellin A, a naturally occurring PKC inhibitor from a Chinese plant. Human umbilical vein endothelial cells (HUVECs) were incubated with 20 mM glucose in both the presence and absence of hypocrellin A, after which, the protein expression and release of VEGF and mRNA expression and release of ET-1 were measured. VEGF and ET-1 were released into the medium and expressions of VEGF protein and ET-1 mRNA were significantly increased in HUVECs incubated with 20 mM glucose. Hypocrellin A (150 nM) significantly decreased VEGF release (117 ± 3 vs. 180 ± 11 pg/mg, p < 0.05) and VEGF protein expression (from 130 ± 14% to 88 ± 18.5%, p < 0.05). ET-1 release was also reduced in hypocrellin A treated HUVECs (63.3 ± 9.9 vs. 75.2 ± 12.6 ng/mg). Hypocrellin A significantly reversed the effect of high glucose on ET-1 mRNA expression ( p < 0.05). The results revealed that PKC activation plays a pivotal role in VEGF and ET-1 mediated endothelial permeability. The naturally occurring compound hypocrellin A may be a potentially novel treatment for endothelial dysfunction in diabetes.

scholarly journals Vascular Endothelial Growth Factor Receptor-2 Expression Is Induced by 17β-Estradiol in ZR-75 Breast Cancer Cells by Estrogen Receptor α/Sp Proteins

Endocrinology ◽  
2006 ◽  
Vol 147 (7) ◽  
pp. 3285-3295 ◽  
Author(s):  
Kelly J. Higgins ◽  
Shengxi Liu ◽  
Maen Abdelrahim ◽  
Kyungsil Yoon ◽  
Kathryn Vanderlaag ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Vascular Endothelial Growth Factor ◽  
Growth Factor ◽  
Chromatin Immunoprecipitation ◽  
Breast Cancer Cells ◽  
Growth Factor Receptor ◽  
Vascular Endothelial ◽  
Rich Region ◽  
17Β Estradiol ◽  
Endothelial Growth Factor

Vascular endothelial growth factor receptor-2 kinase insert domain receptor (VEGFR2/KDR) is critical for angiogenesis, and VEGFR2 mRNA and protein are expressed in ZR-75 breast cancer cells and induced by 17β-estradiol (E2). Deletion analysis of the VEGFR2 promoter indicates that the proximal GC-rich region is required for both basal and hormone-induced transactivation, and mutation of one or both of the GC-rich motifs at −58 and −44 results in loss of transactivation. Electrophoretic mobility shift and chromatin immunoprecipitation assays show that Sp1, Sp3, and Sp4 proteins bind the GC-rich region of the VEGFR2 promoter. Results of the chromatin immunoprecipitation assay also demonstrate that ERα is constitutively bound to the VEGFR2 promoter and that these interactions are not enhanced after treatment with E2, whereas ERα binding to the region of the pS2 promoter containing an estrogen-responsive element is enhanced by E2. RNA interference studies show that hormone-induced activation of the VEGFR2 promoter constructs requires Sp3 and Sp4 but not Sp1, demonstrating that hormonal activation of VEGFR2 involves a nonclassical mechanism in which ERα/Sp3 and ERα/Sp4 complexes activate GC-rich sites where Sp proteins but not ERα bind DNA. These results show for the first time that Sp3 and Sp4 cooperatively interact with ERα to activate VEGFR2 and are in contrast to previous results showing that several hormone-responsive genes are activated by ERα/Sp1 in breast cancer cell lines.

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