Arylhydrocarbon receptor expression in the human endometrium

Area of Science:

• Reproductive biology
• Molecular endocrinology
• Gastroenterology

Background:

• The arylhydrocarbon receptor (AhR), a ligand-activated transcription factor, is implicated in various physiological and pathological processes.
• Its role in human endometrium, particularly during the menstrual cycle, remains largely unexplored.

Purpose of the Study:

• To investigate the expression and cellular localization of the arylhydrocarbon receptor (AhR) in human endometrium throughout the normal menstrual cycle.
• To determine potential correlations between AhR expression, menstrual cycle phase, and patient age.

Main Methods:

• A retrospective study utilizing immunohistochemistry and in situ hybridization on endometrial samples from 86 premenopausal women.
• Samples were collected across different phases of the menstrual cycle (days 3-26).
• Quantification of AhR mRNA and protein expression levels.

Main Results:

• Arylhydrocarbon receptor (AhR) expression was detected in 43% of endometrial samples, showing a significant correlation with the menstrual cycle day.
• Peak AhR immunopositivity was observed around the time of ovulation, with expression decreasing in older patients.
• AhR protein was localized to the apical cytoplasm of endometrial glandular epithelial cells, and its mRNA was found in the cytoplasm.

Conclusions:

• This study demonstrates the presence and cyclical expression of the arylhydrocarbon receptor (AhR) in the human endometrium.
• The findings suggest a potential role for AhR as a transcription factor in regulating endometrial function during the reproductive years.