scholarly journals In vivo analysis of cardiac cell death with age and estrogen deficiency in the female rat: protective effects of acute estrogen receptor‐α activation

2011 ◽  
Vol 25 (S1) ◽  
Author(s):  
Stephanie V. Eldred ◽  
Richard W. Ball ◽  
J. Craig Hunter ◽  
Donna H. Korzick
Keyword(s):  
Cell Death ◽  
Estrogen Receptor ◽  
Estrogen Receptor Α ◽  
Estrogen Deficiency ◽  
Female Rat ◽  
Protective Effects ◽  
Cardiac Cell ◽  
In Vivo Analysis

Multiple forms of estrogen receptor-α in cerebral blood vessels: regulation by estrogen

2003 ◽  
Vol 284 (1) ◽  
pp. E184-E192 ◽  
Author(s):  
Chris Stirone ◽  
Sue P. Duckles ◽  
Diana N. Krause
Keyword(s):  
Estrogen Receptor ◽  
Blood Vessels ◽  
Estrogen Receptor Α ◽  
26S Proteasome ◽  
Target Tissue ◽  
Female Rat ◽  
Cerebral Vasculature ◽  
Cerebral Blood Vessels ◽  
Multiple Forms

The cerebral vasculature is an important target tissue for estrogen, as evidenced by significant effects of estrogen on vascular reactivity and protein levels of endothelial nitric oxide synthase and prostacyclin synthase. However, the presence, localization, and regulation of estrogen receptors in the cerebral vasculature have not been investigated. In this study, we identified the presence of estrogen receptor-α (ER-α) in female rat cerebral blood vessels and localized this receptor to both smooth muscle and endothelial cells by use of immunohistochemistry and confocal microscopy. With immunoblot analysis, multiple forms of ER-α were detected at 110, 93, 82, 50, and 45 kDa in addition to a relatively weak band corresponding to the 66-kDa putative unmodified receptor. The 82-kDa band was identified as Ser118-phosphorylated ER-α, whereas the 50-kDa band lacks the normal NH2 terminus, suggestive of an ER-α splice variant. Lower molecular mass bands persisted after in vivo inhibition of 26S proteasome activity with lactacystin, whereas the 110- and 93-kDa bands increased. All forms of ER-α in cerebral vessels were decreased after ovariectomy but significantly increased after chronic estrogen exposure in vivo.

scholarly journals Humanin is an endogenous activator of chaperone-mediated autophagy

2017 ◽  
Vol 217 (2) ◽  
pp. 635-647 ◽  
Author(s):  
Zhenwei Gong ◽  
Inmaculada Tasset ◽  
Antonio Diaz ◽  
Jaime Anguiano ◽  
Emir Tas ◽  
...  
Keyword(s):  
Quality Control ◽  
Cell Death ◽  
Heat Shock Protein 90 ◽  
Protective Effects ◽  
Neuroprotective Effects ◽  
Selective Degradation ◽  
Cytosolic Side ◽  
Chaperone Mediated Autophagy

Chaperone-mediated autophagy (CMA) serves as quality control during stress conditions through selective degradation of cytosolic proteins in lysosomes. Humanin (HN) is a mitochondria-associated peptide that offers cytoprotective, cardioprotective, and neuroprotective effects in vivo and in vitro. In this study, we demonstrate that HN directly activates CMA by increasing substrate binding and translocation into lysosomes. The potent HN analogue HNG protects from stressor-induced cell death in fibroblasts, cardiomyoblasts, neuronal cells, and primary cardiomyocytes. The protective effects are lost in CMA-deficient cells, suggesting that they are mediated through the activation of CMA. We identified that a fraction of endogenous HN is present at the cytosolic side of the lysosomal membrane, where it interacts with heat shock protein 90 (HSP90) and stabilizes binding of this chaperone to CMA substrates as they bind to the membrane. Inhibition of HSP90 blocks the effect of HNG on substrate translocation and abolishes the cytoprotective effects. Our study provides a novel mechanism by which HN exerts its cardioprotective and neuroprotective effects.

scholarly journals Loading-related regulation of gene expression in bone in the contexts of estrogen deficiency, lack of estrogen receptor α and disuse

Bone ◽  
2010 ◽  
Vol 46 (3) ◽  
pp. 628-642 ◽  
Author(s):  
Gul Zaman ◽  
Leanne K. Saxon ◽  
Andrew Sunters ◽  
Helen Hilton ◽  
Peter Underhill ◽  
...  
Keyword(s):  
Gene Expression ◽  
Estrogen Receptor ◽  
Regulation Of Gene Expression ◽  
Estrogen Receptor Α ◽  
Estrogen Deficiency

HIV replication elicits little cytopathic effects in vivo: Analysis of surrogate markers for virus production, cytotoxic T cell response and infected cell death

2006 ◽  
Vol 78 (9) ◽  
pp. 1141-1146 ◽  
Author(s):  
Georg A. Funk ◽  
Annette Oxenius ◽  
Marek Fischer ◽  
Milos Opravil ◽  
Beda Joos ◽  
...  
Keyword(s):  
Cell Death ◽  
Infected Cell ◽  
Virus Production ◽  
T Cell Response ◽  
Cytotoxic T Cell ◽  
Surrogate Markers ◽  
Hiv Replication ◽  
Cytopathic Effects ◽  
In Vivo Analysis

scholarly journals Nuclear Activation Function 2 Estrogen Receptor α Attenuates Arterial and Renal Alterations Due to Aging and Hypertension in Female Mice

2020 ◽  
Vol 9 (5) ◽  
Author(s):  
Emmanuel Guivarc'h ◽  
Julie Favre ◽  
Anne‐Laure Guihot ◽  
Emilie Vessières ◽  
Linda Grimaud ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Estrogen Receptor ◽  
Angiotensin Ii ◽  
Systolic Blood Pressure ◽  
Vascular Reactivity ◽  
Nuclear Gene ◽  
Estrogen Receptor Α ◽  
Protective Effects ◽  
Wild Type ◽  
Female Mice

Background The cardiovascular protective effects of estrogens in premenopausal women depend mainly on estrogen receptor α (ERα). ERα activates nuclear gene transcription regulation and membrane‐initiated signaling. The latter plays a key role in estrogen‐dependent activation of endothelial NO synthase. The goal of the present work was to determine the respective roles of the 2 ERα activities in endothelial function and cardiac and kidney damage in young and old female mice with hypertension, which is a major risk factor in postmenopausal women. Methods and Results Five‐ and 18‐month‐old female mice lacking either ERα (ERα −/− ), the nuclear activating function AF2 of ERα (AF2°), or membrane‐located ERα (C451A) were treated with angiotensin II (0.5 mg/kg per day) for 1 month. Systolic blood pressure, left ventricle weight, vascular reactivity, and kidney function were then assessed. Angiotensin II increased systolic blood pressure, ventricle weight, and vascular contractility in ERα −/− and AF2° mice more than in wild‐type and C451A mice, independent of age. In both the aorta and mesenteric resistance arteries, angiotensin II and aging reduced endothelium‐dependent relaxation in all groups, but this effect was more pronounced in ERα −/− and AF2° than in the wild‐type and C451A mice. Kidney inflammation and oxidative stress, as well as blood urea and creatinine levels, were also more pronounced in old hypertensive ERα −/− and AF2° than in old hypertensive wild‐type and C451A mice. Conclusions The nuclear ERα‐AF2 dependent function attenuates angiotensin II–dependent hypertension and protects target organs in aging mice, whereas membrane ERα signaling does not seem to play a role.

scholarly journals Estrogen modulates the recruitment of myelopoietic cell progenitors in rat through a stromal cell-independent mechanism involving apoptosis

Blood ◽  
1996 ◽  
Vol 87 (7) ◽  
pp. 2683-2692 ◽  
Author(s):  
NK Shevde ◽  
JW Pike
Keyword(s):  
Estrogen Receptor ◽  
Ovarian Function ◽  
Morphological Changes ◽  
Estrogen Treatment ◽  
Ovariectomized Rats ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Protective Effects ◽  
Hematopoietic Stem

Loss of ovarian function leads to a significant increase in the number of bone-resorbing osteoclasts. Estrogen replacement is known to manifest bone protective effects in the treatment of postmenopausal osteoporosis. In the present study, we used ovariectomized rats to examine the effects of estrogen loss at the osteoclast progenitor colony forming unit-granulocyte macrophage (CFU-GM) level. A significant increase in CFU-GM number was observed as early as 7 days following ovariectomy, and correlated directly with an increase in the number of osteoclast-like cells generated in marrow cultures. The increase in CFU-GM following ovariectomy was abrogated in animals that received estrogen treatment in vivo. A similar suppressive effect was observed on CFU-GM number when ovariectomized rat marrow was treated with estrogen in vitro. This effect was blocked in the presence of the estrogen antihormone ICI 164,384. Thus, the data suggest the possibility that estrogen exerts a direct effect on osteoclast progenitors, and does so through the estrogen receptor-mediated mechanism. Ovariectomy also led to an increase in the early hematopoietic stem/progenitor cell population (Thy 1.1+ cells) as determined by FLOW cytometry methods. Morphological changes as well as terminal deoxynucleotidyl transferase assays revealed that estrogen treatment negated growth factor-induced proliferation of these early progenitors by promoting apoptosis. The cellular effects of estrogen in vitro together with the immunocytochemical detection of the estrogen receptor in these cells, strongly support the contention that in addition to osteoclast progenitors such as CFU-GM, earlier hematopoietic progenitors are also unique cellular targets for estrogen action.

scholarly journals Comparative study of estrogen receptor α, β mRNA expressions of endometriosis and normal endometrium in women and analysis of potential synthetic anti-estrogens in silico

2018 ◽  
Vol 91 (2) ◽  
Author(s):  
Eldafira Eldafira ◽  
Abinawanto Abinawanto ◽  
Luthfiralda Sjahfirdi ◽  
Asmarinah Asmarinah ◽  
Purnomo Soeharso ◽  
...  
Keyword(s):  
Estrogen Receptor ◽  
Mrna Expression ◽  
Estrogen Receptor Α ◽  
Assay Method ◽  
Enzyme Linked Immunosorbent Assay ◽  
Normal Endometrium ◽  
Pcr Method ◽  
Genetic And Environmental Factors

Endometriosis is a multifactorial disease in which genetic and environmental factors interact causing its pathogenesis. The aim of this study was to investigate the expression pattern of estrogen receptor α (ERα) and β (ERβ) in endometriosis patients compared to normal endometrioum (n=18) as a control by using Quantitative Real Time PCR method. Moreover, we also measured serum estradiol levels of endometriosis patients in the proliferation phase of the menstrual cycle using the enzyme-linked immunosorbent assay method. The mRNA expression of ERβ was significantly higher in the endometriosis group compared to control, and the result of t-test showed that were significantly different (P<0.05). Overexpression of ERβ in endometriosis was likely to have other significant important impacts in the pathology of endometriosis that allowed ERβ to stimulate prostaglandin production in endometriosis tissue and cells. Estradiol content did not correlate with the ERα expression, and it is weakly correlated with ERβ mRNA expression. Molecular docking analysis showed that ERα and ERβ have different binding interactions with synthetic antiestrogens, whereas the best inhibitor was Ral2 to ERα and Aco1 to ERβ. Thus, both inhibitors could be used as leads in further investigation of ERα, ERβ inhibitory activities in vitro and in vivo.

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