Search results for "Apoptosis."
showing 10 items of 1794 documents
The Human Blastocyst Regulates Endometrial Epithelial Apoptosis in Embryonic Adhesion1
2000
The implanting blastocyst must appose and adhere to the endometrial epithelium and, subsequently, invade it. Locally regulated uterine epithelial apoptosis induced by the embryo is a crucial step of the epithelial invasion in rodents. To address the physiological relevance of this process in humans, we investigated the effect of single human blastocysts on the regulation of apoptosis in cultured human endometrial epithelial cells (hEEC) in both apposition and adhesion phases of implantation. Here, we report a co-ordinated embryonic regulation of hEEC apoptosis. In the apposition phase, the presence of a blastocyst rescues hEEC from the apoptotic pathway. However, when the human blastocyst a…
Nitric oxide triggers mammary gland involution after weaning: remodelling is delayed but not impaired in mice lacking inducible nitric oxide synthase
2010
During mammary gland involution, different signals are required for apoptosis and tissue remodelling. To explore the role of NO in the involution of mammary tissue after lactation, NOS2 (inducible nitric oxide synthase)-KO (knockout) mice were used. No apparent differences were observed between NOS2-KO and WT (wild-type) animals during pregnancy and lactation. However, upon cessation of lactation, a notable delay in involution was observed, compared with WT mice. NOS2-KO mice showed increased phosphorylation of STAT (signal transducer and activator of transcription) 5 during weaning, concomitant with increased beta-casein mRNA levels when compared with weaned WT glands, both hallmarks of th…
A caspase-3-dependent pathway is predominantly activated by the excitotoxin pregnenolone sulfate and requires early and late cytochrome c release and…
2002
This study investigates the implication of mitochondria- and caspase-dependent pathways in the death of retinal neurones exposed to the neurosteroid pregnenolone sulfate (PS) shown to evoke apoptosis and contribute to amplification and propagation of excitotoxicity. After a brief PS challenge of intact retinas, caspase-3 and caspase-2 activation and cytochrome c release occur early and independent of changes in the oxidative state measured by superoxide dismutase activity. The temporal and spatial relationship of these events suggests that a caspase-3-dependent pathway is activated in response to cytochrome c release and requires caspase-2 activation and a late cytochrome c release in speci…
Acute estradiol protects CA1 neurons from ischemia-induced apoptotic cell death via the PI3K/Akt pathway
2010
Global ischemia arising during cardiac arrest or cardiac surgery causes highly selective, delayed death of hippocampal CA1 neurons. Exogenous estradiol ameliorates global ischemia-induced neuronal death and cognitive impairment in male and female rodents. However, the molecular mechanisms by which a single acute injection of estradiol administered after the ischemic event intervenes in global ischemia-induced apoptotic cell death are unclear. Here we show that acute estradiol acts via the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling cascade to protect CA1 neurons in ovariectomized female rats. We demonstrate that global ischemia promotes early activation of glycogen syn…
Estrogen regulates cytokine production and apoptosis in PMA-differentiated, macrophage-like U937 cells
2003
We have investigated the effects of sex steroids, estradiol (E2), and testosterone (T) on the synthesis of tumor necrosis factor alpha (TNF-alpha) and interleukin-10 (IL-10) in phorbol-myristate-acetate (PMA)-differentiated human monoblastic U937 cells. The ability of both hormones to modulate the viability and programmed cell death of macrophage-like PMA-differentiated U937 cells was also inspected. E2 increased TNF-alpha synthesis, whereas T had no effect on the production of this cytokine. The combination of E2 and its antagonist tamoxifen or ICI-182,789 completely abolished the induction of TNF-alpha, while combination of T and its antagonist Casodex (CSDX) did not significantly affect …
Retinoids induce MMP-9 expression through RARalpha during mammary gland remodeling.
2007
Retinoic acid (RA) is a signaling molecule in the morphogenesis of the mammary gland, modulating the expression of matrix metalloproteinases (MMPs). The aim of this paper was to study the role of RA during weaning, which consists of three events: apoptosis of the secretory cells, degradation of the extracellular matrix, and adipogenesis. CRABP II and CRBP-1 carrier proteins increased significantly during weaning compared with lactating glands but reverted to control values after the litter resuckled. The effects of RA are mediated by the nuclear receptors RARalpha, RARbeta, RARgamma, and RXRalpha, which underwent an increase in protein levels during weaning. In an attempt to elucidate the R…
The antiapoptotic protein BAG3 is expressed in thyroid carcinomas and modulates apoptosis mediated by tumor necrosis factor-related apoptosis-inducin…
2007
Abstract Context: We previously showed that BAG3 protein, a member of the BAG (Bcl-2-associated athanogene) co-chaperone family, modulates apoptosis in human leukemias. The expression of BAG3 in other tumor types has not been extensively investigated so far. Objective: The objective of this study was to analyze BAG3 expression in thyroid neoplastic cells and investigate its influence in cell apoptotic response to TNF-related apoptosis-inducing ligand (TRAIL). Design, Setting, and Patients: We investigated BAG3 expression in human thyroid carcinoma cell lines, including NPA, and the effect of BAG3-specific small interfering RNA on TRAIL-induced apoptosis in NPA cells. Subsequently, we analyz…
Retarded thymic involution and massive germinal center formation in NF-ATp-deficient mice.
1998
NF-ATp and NF-ATc are the most prominent nuclear NF-AT transcription factors in peripheral T lymphocytes. After T cell activation both factors bind to and control the promoters and enhancers of numerous lymphokine and receptor ligand genes. In order to define a specific role for NF-ATp in vivo we have inactivated the NF-ATp gene by gene targeting in mice. We show that NF-ATp deficiency leads to the accumulation of peripheral T cells with a “preactivated” phenotype, enhanced immune responses of T cells after secondary stimulation in vitro and severe defects in the proper termination of antigen responses, as shown by a reduced deletion of superantigen-reactive CD4+ T cells. These alterations …
Small airways in in sedentary and endurance-trained dystrophic (mdx) mice
2015
The effects of mild endurance exercise training on the small airways in mdx mice are unknown. We compared epithelial thickness and turnover, apoptosis, and stress marker expression in small airways of mdx mice and wild-type (WT) controls, at rest and during exercise training. Mdx and WT mice were randomly assigned to sedentary (mdx-S, n=17; WT-S, n=19) or trained (mdx-EX, n=14; WT-EX, n=16) groups. Low-intensity endurance training (running on a wheel) was done 5 d/wk for 6 wk at progressively increasing speed (rpm from 16 to 24) and time (15 min to 1 h). Lungs were processed for light microscopy and periodic acid Schiff (PAS) staining. Hsp60 and PCNA were quantified by immunohistochemistry.…
Stress hormones promote growth of B16-F10 melanoma metastases: an interleukin 6- and glutathione-dependent mechanism
2013
[EN] Background: Interleukin (IL)-6 (mainly of tumor origin) activates glutathione (GSH) release from hepatocytes and its interorgan transport to B16-F10 melanoma metastatic foci. We studied if this capacity to overproduce IL-6 is regulated by cancer cell-independent mechanisms. Methods: Murine B16-F10 melanoma cells were cultured, transfected with red fluorescent protein, injected i.v. into syngenic C57BL/6J mice to generate lung and liver metastases, and isolated from metastatic foci using high-performance cell sorting. Stress hormones and IL-6 levels were measured by ELISA, and CRH expression in the brain by in situ hybridization. DNA binding activity of NF-kappa B, CREB, AP-1, and NF-IL…