Search results for "Estrogens"

Phytoestrogens Up-regulate Antioxidant Genes

2009

RASSF1A inhibits estrogen receptor alpha expression and estrogen-independent signalling: implications for breast cancer development

2012

The Ras association domain family 1 isoform A (RASSF1A) is a tumor suppressor whose inactivation is implicated in the development of many human cancers, including breast carcinomas. Little is known about the tumor-suppressive function of RASSF1A in breast tissue and whether its inactivation is mechanistically involved in the initiation and progression of breast tumors. Here, we show that RASSF1A inhibits breast cancer growth in vivo, and suppresses estrogen receptor (ERα) expression and function. Reconstitution of RASSF1A in MCF7 cells led to decreased ERα levels and reduced sensitivity to estrogen (E2). Concomitantly, we observed decreased expression of Id1 as well as the E2-responsive gen…

Daidzein has neuroprotective effects through ligand-binding-independent PPARγ activation.

2011

Phytoestrogens are a group of plant-derived compounds that include mainly isoflavones like daidzein. Phytoestrogens prevent neuronal damage and improve outcome in experimental stroke; however, the mechanisms of this neuroprotective action have not been fully elucidated. In this context, it has been postulated that phytoestrogens might activate the peroxisome proliferator-activated receptor-γ (PPARγ), which exerts neuroprotective effects in several settings. The aim of this study was to determine whether the phytoestrogen daidzein elicits beneficial actions in neuronal cells by mechanisms involving activation of PPARγ. Our results show that daidzein (0.05-5 μM) decreases cell death induced b…

Targeting the vascular endothelial growth factor system to prevent ovarian hyperstimulation syndrome

2008

BACKGROUND: Ovarian hyperstimulation syndrome (OHSS) typically occurs when ovaries are primed with FSH/ LH and subsequently exposed to hCG. The ultimate pathophysiological step underlying this clinical picture is increased vascular permeability (VP). METHODS: A search of the literature was carried out using PubMed and the authors’ files. RESULTS: In rodents and humans, the expression of vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR-2) mRNA increases during ovarian stimulation. With the administration of hCG, the expression of each rises to a maximum. Expression of VEGF/VEGFR-2 mRNAs correlates with enhanced VP, with both peaking 48 h following an injection of hCG. Imm…

The non-aromatizable androgen dihydrotestosterone (DHT) facilitates sexual behavior in ovariectomized female rats primed with estradiol

2020

Abstract It is still unclear whether Testosterone (T) increases sexual desire through a stimulation of the androgen receptor in relevant brain regions or through its conversion to estrogens. The aim of this study was to clarify the mechanisms of T facilitation of female sexual desire by assessing the effect of a non-aromatizable androgen (Dihydrotestosterone, DHT) in a validated animal model. Ovariectomized (OVX) Long-Evans rats were treated with oil (O) + O, 10 mcg Estradiol Benzoate (EB) + O, 10 mcg EB + 500 mcg Progesterone (P), O + 500 mcg DHT or 10 mcg EB + 500 mcg DHT (n = 12 per group). EB was administered 48 h, while P and DHT 4 h, prior to 4 sexual behavioral testing sessions in bi…

Análisis del perfil de expresión de microRNA en células endoteliales humanas expuestas a estradiol. Papel del miR-30b-5p en la regulación de la expre…

2017

El endotelio es un tejido dinámico que juega un papel fundamental en el mantenimiento de la función vascular. Está localizado en la capa interna de los vasos sanguíneos, linfáticos y corazón, y resulta clave para las diversas funciones del sistema cardiovascular, tales como la hemostasia, la regulación del tono vascular, la respuesta inflamatoria, la regulación de la permeabilidad vascular y la angiogénesis. El endotelio actúa como una diana de los estrógenos y expresa ambos tipos de receptores de estrógenos (ER): los nucleares clásicos ERα and ERβ, que actúan como factores de transcripción, y el receptor acoplado a proteína G (GPER). Mientras que la unión de estrógenos a ERα y ERβ modula l…

Aging of the musculoskeletal system: How the loss of estrogen impacts muscle strength.

2019

Skeletal muscle weakness occurs with aging and in females this is compounded by the loss of estrogen with ovarian failure. Estrogen deficiency mediates decrements in muscle strength from both inadequate preservation of skeletal muscle mass and decrements in the quality of the remaining skeletal muscle. Processes and components of skeletal muscle that are affected by estrogens are beginning to be identified. This review focuses on mechanisms that contribute to the loss of muscle force generation when estrogen is low in females, and conversely the maintenance of strength by estrogen. Evidence is accumulating that estrogen deficiency induces apoptosis in skeletal muscle contributing to loss of…

Data from Estrogenic Regulation of Muscle Apoptosis (ERMA) study

2022

The multidisciplinary Estrogenic Regulation of Muscle Apoptosis (ERMA) study was designed to reveal how hormonal differences over the menopausal stages affect the physiological and psychological functioning of middle-aged women. In addition, health behaviour (e.g., physical activity and eating behaviour) and blood-based biomarkers are investigated. Biomarker data includes different omics datasets (e.g. metabolomics, genomics, transcriptomics). The complete data set includes baseline data collection and two different follow-ups. The baseline ERMA study (=parent data) is a population-based cohort study, which forms a parent data set for the follow-up studies (ERMA follow-up and EsmiRs). Data …

Towards powerful old age : association between hormone replacement therapy and skeletal muscle

2010

In utero exposure to mixtures of xenoestrogens and child neuropsychological development.

2014

BACKGROUND: To date, no epidemiological studies have explored the impact and persistence of in utero exposure to mixtures of xenoestrogens on the developing brain. We aimed to assess whether the cumulative effect of xenoestrogens in the placenta is associated with altered infant neuropsychological functioning at two and at four years of age, and if associations differ among boys and girls. METHODS: Cumulative prenatal exposure to xenoestrogens was quantified in the placenta using the biomarker Total Effective Xenoestrogen Burden (TEXB-alpha) in 489 participants from the INMA (Childhood and the Environment) Project. TEXB-alpha was split in tertiles to test its association with the mental and…