Related Experiment Video
Updated: Sep 13, 2025
08:02
Visualization of Estrogen Receptors in Colons of Mice with TNBS-Induced Crohn's Disease using Immunofluorescence
Published on: March 12, 2020
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G-Protein-Coupled Estrogen Receptor (GPER) in Inflammatory Myopathies
Delia Righi1, Diego Lopergolo1,2, Nila Volpi1
1Department of Medical, Surgical and Neurological Sciences, University of Siena, 53100 Siena, Italy.
Neurology International
|July 25, 2025
Summary
G-protein-coupled estrogen receptor (GPER) is upregulated in inflammatory myopathies (IM), suggesting a protective role. This finding opens avenues for GPER agonist therapies for IM treatment.
Area of Science:
- Endocrinology
- Immunology
- Neurology
Background:
- Estrogen hormones influence skeletal muscle pathophysiology and possess immunomodulatory properties.
- The G-protein-coupled estrogen receptor (GPER) role in skeletal muscle requires further elucidation, particularly in inflammatory conditions.
Purpose of the Study:
- To characterize GPER expression in human skeletal muscle of patients with inflammatory myopathies (IM).
- To investigate the correlation between GPER expression and disease severity in IM.
Main Methods:
- Immunohistochemical analysis of muscle biopsies from IM patients, non-inflammatory myopathies (N.IM) patients, and controls.
- Statistical evaluation of GPER scores and Visual Analog Scale (VAS) for disease pathology assessment.
Main Results:
- GPER is constitutively expressed in human skeletal muscle and significantly upregulated in IM.
- Enhanced GPER expression, both sarcolemmal and intracellular, positively correlated with the severity of muscle inflammation.
- IM patients exhibited significantly higher VAS scores compared to N.IM and control groups.
Conclusions:
- This study provides the first histopathological characterization of GPER in human skeletal muscle.
- Upregulated GPER in IM may exert a protective effect by modulating inflammatory mediator release.
- GPER agonists represent a potential therapeutic strategy for inflammatory myopathies.
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