Project description:This experiment investigates the functional roles of estrogen receptor alpha and beta in peripheral blood leukocytes by using selective estrogen receptor agonists. The agonists that are used are estradiol (E2), the selective ER-alpha agonist PPT (4,4',4''-(4-Propyl-[1H]-pyrazole-1,3,5-triyl)trisphenol) and the selective ER-beta agonist DPN (2,3-bis(4-hydroxyphenyl)-propionitrile).
Project description:In addition to their role in the development and function of the reproductive system, estrogens have significant anti-inflammatory properties. Although both estrogen receptors (ERs) can mediate anti-inflammatory actions, ERbeta is a more desirable therapeutic target because ERalpha mediates the proliferative effects of estrogens on the mammary gland and uterus. In fact, selective ERbeta agonists have beneficial effects in preclinical models involving inflammation without causing growth-promoting effects on the uterus or mammary gland. However, their mechanism of action is unclear. The purpose of this study was to use microarray analysis to determine whether ERbeta-selective compounds produce their anti-inflammatory effects by repressing transcription of proinflammatory genes. We identified 49 genes that were activated by TNF-alpha in human osteosarcoma U2OS cells expressing ERbeta. Estradiol treatment significantly reduced the activation by TNF-alpha on 18 genes via ERbeta or ERalpha. Most repressed genes were inflammatory genes, such as TNF-alpha, IL-6, and CSF2. Three ERbeta-selective compounds, ERB-041, WAY-202196, and WAY-214156, repressed the expression of these and other inflammatory genes. ERB-041 was the most ERbeta-selective compound, whereas WAY-202196 and WAY-214156 were the most potent. The ERbeta-selective compounds repressed inflammatory genes by recruiting the coactivator, SRC-2. ERB-041 also repressed cytokine genes in PBMCs, demonstrating that ERbeta-selective estrogens have anti-inflammatory properties in immune cells. Our study suggests that the anti-inflammatory effects of ERB-041 and other ERbeta-selective estrogens in animal models are due to transcriptional repression of proinflammatory genes. These compounds might represent a new class of drugs to treat inflammatory disorders. Keywords: estrogen receptor, gene regulation, TNF
Project description:Estrogen receptor beta (ERbeta) has potent anti-proliferative and anti-inflammatory properties, suggesting that ER beta-selective agonists might be a new class of therapeutic and chemopreventative agents. To understand how ER beta regulates genes, we identified genes regulated by the unliganded and liganded forms of ER alpha and ER beta in U2OS cells. Microarray data demonstrated that virtually no gene regulation occurred with unliganded ER alpha, whereas many genes were regulated by estradiol (E2). These results demonstrate ER alpha requires a ligand to regulate a single class of genes. In contrast, ER beta regulated three classes of genes. Class I genes were regulated primarily by unliganded ER beta. Class II genes were regulated only with E2, whereas Class III genes were regulated by both unliganded ER beta and E2. There were 453 Class I genes, 258 Class II genes and 83 Class III genes. To explore the mechanism whereby ER beta regulates different classes of genes ChIP-seq was performed to identify ER beta binding sites and adjacent transcription factor motifs in regulated genes. AP1 binding sites were more enriched in Class I genes, whereas ERE, NFKB1 and SP1 sites were more enriched in class II genes. ER beta bound to all three classes of genes demonstrating that ER beta binding is not responsible for differential regulation of genes by unliganded and liganded ER beta. The coactivator, NCOA2 was differentially recruited to several target genes. Our findings indicate that the unliganded and liganded forms of ER beta regulate three classes of genes by interacting with different transcription factors and coactivators. Examination of ER beta binding sites in U2OS cells with or without E2 treatment
Project description:We have used an agnostic approach to identify drug combinations by using combination high throughput screening (cHTS) technology and make the surprising discovery that adenosine A2A and beta-2 adrenergic receptor agonists are highly synergistic, selective and novel agents that enhance glucocorticoid activity in B-cell malignancies. We used the microarray study to understand the synergistic mechanism between dexamethasone and A2A receptor agonist or Beta-2 Adrenergic receptor agonist in a multiple myeloma cell line, MM1S. MM1S cells were treated with CGS-21680 or Salmeterol alone, or in combination with dexamethasone for six hours for RNA extraction and hybridization on Affymetrix microarrays.
Project description:Activation of the sympathetic nervous system causes pronounced metabolic changes that are mediated by multiple adrenergic receptor subtypes. Systemic treatment with β<sub>2-</sub>adrenergic receptor agonists results in multiple beneficial metabolic effects, including improved glucose homeostasis. To elucidate the underlying cellular and molecular mechanisms, we chronically treated wild-type mice and several newly developed mutant mouse strains with clenbuterol, a selective β<sub>2</sub>-adrenergic receptor agonist. Clenbuterol administration caused pronounced improvements in glucose homeostasis and prevented the metabolic deficits in mouse models of β-cell dysfunction and insulin resistance. Studies with skeletal muscle-specific mutant mice demonstrated that these metabolic improvements required activation of skeletal muscle β<sub>2</sub>-adrenergic receptors and the stimulatory G protein, G<sub>s</sub>. Unbiased transcriptomic and metabolomic analyses showed that chronic β<sub>2</sub>-adrenergic receptor stimulation caused metabolic reprogramming of skeletal muscle characterized by enhanced glucose utilization. These findings strongly suggest that agents targeting skeletal muscle metabolism by modulating β<sub>2</sub>-adrenergic receptor-dependent signaling pathways may prove beneficial as antidiabetic drugs.
Project description:To find out the potential targets in response to estrogen treatment on ACHN cell, a human renal cell carcinoma (RCC) cell line. Since estrogen can repress ACHN growth in a partly estrogen receptor-dependent manner, it is possible that phosphorylation state in ACHN cells is regulated.