Estrogen regulates transcription factors STAT-1 and NF-kappaB to promote inducible nitric oxide synthase and inflammatory responses.

J Immunol

Center for Molecular Medicine and Infectious Diseases, Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA 24060, USA.

Published: December 2009

Estrogen regulation of inflammatory responses has broad physiological and pathological consequences. However, the molecular mechanism of estrogen regulation of inflammation is still poorly understood. In this study, we report that activation of both STAT-1 and NF-kappaB signaling is essential for Con A-induced inducible NO synthase (iNOS) and NO in murine splenocytes. Estrogen enhances STAT-1 DNA-binding activity without increasing the expression of phosphorylated and total STAT-1 protein. We have recently reported that estrogen blocks the nuclear expression of NF-kappaB p65 and modifies nuclear NF-kappaBp50. Here, we demonstrated that both nuclear STAT-1 and NF-kappaB are modified by serine protease-mediated proteolysis, which resulted in altered STAT-1 and NF-kappaB activity/signaling in splenocytes from estrogen-treated mice. Inhibition of serine protease activity with 4-(2-aminoethyl)benzenesulfonyl fluoride hydrochloride (AEBSF) restores the nuclear expression of full-length STAT-1 and NF-kappaB proteins, and resulted in decreased STAT-1 DNA-binding activity and formation of NF-kappaB p65/p50 binding complexes in nuclei of splenocytes from estrogen-treated mice. Consequently, there is significantly decreased iNOS and IFN-gamma production in AEBSF-treated splenocytes from estrogen-treated mice, which suggests a positive regulatory role of truncated STAT-1 and/or NF-kappaB. Interestingly, there is increased production of MCP-1 in STAT-1 or NF-kappaB small interfering RNA-transfected cells, as well as in AEBSF-treated splenocytes from estrogen-treated mice. These data suggest a differential role of truncated STAT-1 and NF-kappaB in regulation of various inflammatory molecules in splenocytes from estrogen-treated mice. Together, our data reveal a novel molecular mechanism of estrogen-mediated promotion of inflammatory responses, which involves posttranslational modification of STAT-1 and NF-kappaB proteins.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2782783PMC
http://dx.doi.org/10.4049/jimmunol.0901737DOI Listing

Publication Analysis

Top Keywords

stat-1 nf-kappab
32
splenocytes estrogen-treated
20
estrogen-treated mice
20
stat-1
12
inflammatory responses
12
nf-kappab
11
estrogen regulation
8
regulation inflammatory
8
molecular mechanism
8
stat-1 dna-binding
8

Similar Publications

Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by immune dysregulation and excessive cytokine production. This study aimed to explore the potential of Camellia sinensis L. water extract (CSE) as a treatment for AD by the impact of CSE on inflammatory responses in keratinocytes, particularly concerning the production of inflammatory cytokines and the modulation of signaling pathways relevant to AD pathogenesis.

View Article and Find Full Text PDF

DOC2b enrichment mitigates proinflammatory cytokine-induced CXCL10 expression by attenuating IKKβ and STAT-1 signaling in human islets.

Metabolism

January 2025

Department of Molecular and Cellular Endocrinology, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute of City of Hope, Duarte, CA, USA. Electronic address:

Introduction: Type 1 diabetic human islet β-cells are deficient in double C 2 like domain beta (DOC2b) protein. Further, DOC2b protects against cytokine-induced pancreatic islet β-cell stress and apoptosis. However, the mechanisms underpinning the protective effects of DOC2b remain unknown.

View Article and Find Full Text PDF

Introduction: Type 1 diabetic human islet β-cells are deficient in double C 2 like domain beta (DOC2b) protein. Further, DOC2b protects against cytokine-induced pancreatic islet β-cell stress and apoptosis. However, the mechanisms underpinning the protective effects of DOC2b remain unknown.

View Article and Find Full Text PDF

Inhibitory Effects of Decursin Derivative against Lipopolysaccharide-Induced Inflammation.

Pharmaceuticals (Basel)

October 2024

Research Institute of Pharmaceutical Sciences, College of Pharmacy, Kyungpook National University, Daegu 41566, Republic of Korea.

Background: This study aims to explore the protective role of JB-V-60-a novel synthetic derivative of decur-sin-against lipopolysaccharide (LPS)-induced inflammation.

Methods: We examined the effects of JB-V-60 on heme oxygenase (HO)-1, cyclooxygenase (COX)-2, and inducible nitric oxide synthase (iNOS) in LPS-activated human pulmonary artery endothelial cells (HPAECs). Additionally, we assessed its effects on iNOS, tumor necrosis factor (TNF)-α, and interleukin (IL)-1β in LPS-exposed mice.

View Article and Find Full Text PDF

Several natural products are being studied to identify new bioactive molecules with therapeutic potential for infections, immune modulation, and other pathologies. TLRs are a family of receptors that play a crucial role in the immune system, constituting the first line of immune defense. They recognize specific products derived from microorganisms that activate multiple pathways and transcription factors in target cells, which are vital for producing immune mediators.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!