Does aberrant expression of cyclooxygenase-2 and prostaglandin-E2 receptor genes lead to abortion in Chlamydia trachomatis-infected women

Abstract

Objective: The aim of the study was to characterize the expression of cyclooxygenase-2 (COX-2) and prostaglandin-E2 (PGE2) genes in spontaneously aborted tissues from women infected with Chlamydia trachomatis.

Methods: A total of 135 spontaneous aborters (Group I) and 45 induced aborters (controls; Group II) attending Obstetrics and Gynaecology Department at Safdarjung hospital (New Delhi, India), were enrolled. Polymerase chain reaction (PCR) assay was performed to detect C. trachomatis DNA in endometrial curettage tissue (ECT). Differential expression of COX-2 and PGE2 receptors at mRNA level was analysed in ECT using reverse transcription PCR and real-time PCR.

Results: In total, 14.8% patients were diagnosed as C. trachomatis-positive in Group I whereas all control patients were C. trachomatis-negative. Qualitative expression of COX-2 (p < 0.05) and PGE2 (p < 0.0001) receptors was found increased in C. trachomatis-positive patients (Group I) in comparison to controls. Quantitative real-time PCR analysis also showed upregulation in transcript levels of both COX-2 (p < 0.002) and PGE2 (p < 0.0001) receptors in infected patients (Group I) versus Group II. COX-2 and PGE2 expression was higher (p < 0.002) in recurrent spontaneous aborters in comparison to sporadic spontaneous aborters.

Conclusions: Results suggest that chlamydial infection leads to upregulation of COX-2 in C. trachomatis-positive recurrent spontaneous aborters, which probably mediates increased prostaglandin synthesis.

• Differential gene expression
• endometrial curettage tissue
• genitourinary chlamydial infection
• real-time PCR
• recurrent spontaneous aborters

Declaration of interest

The authors have no conflicts of interest regarding the content of this work. Authors alone are responsible for the content and writing of this article.

Ms. Namita Singh is thankful to University Grants Commission (UGC), New Delhi, India and Indian Council of Medical Research (ICMR), New Delhi, India for Research Fellowship. Ms. Priya Prasad gratefully acknowledges the award of Junior Research Fellowship (JRF) by Council of Scientific and Industrial Research (CSIR), New Delhi, India.