The Relationship Between Expression of PTGS2, HAS-2, and GREM1 Genes and Reduction of Oocyte Quality in Follicular Fluid of Women with Endometriosis
The Relationship Between Expression of PTGS2, HAS-2, and GREM1 Genes and Reduction of Oocyte Quality in Follicular Fluid of Women with Endometriosis
Fatemeh Bashirian Alvars,1Raha Favaedi,2Azam Dalman,3Fatemeh Hassani,4Maryam Shahhoseini,5,*
1. 1. Faculty of Basic Sciences and Advanced Technologies in Biology, University of science and culture, Tehran, Iran/ 2. Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran 2. Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran 3. Department of Embryology, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran 4. Department of Embryology, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran 5. Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
Introduction: Endometriosis (EM) is a benign, estrogen-dependent, and inflammatory disease that affects approximately 10% of women of reproductive age. This condition is characterized by the presence of functional endometrial tissue and stromal glands located outside the uterine cavity. Epidemiological and clinical studies have established a link between infertility and EM; however, the underlying mechanisms contributing to infertility associated with EM remain varied and not fully understood. EM may influence female fertility by interfering with embryo implantation, causing hormonal alterations, and diminishing oocyte quality. Consequently, the assessment of oocyte status via indirect methods can help in determining the quality of oocytes in women diagnosed with EM. Follicular fluid (FF) serves as a significant clinical approach for evaluating oocyte condition; as it contains metabolites that are closely related to the follicular development, the stage of EM, and the associated fertility outcomes.
An analysis of genes associated with the cumulus expansion process, such as prostaglandin-endoperoxide synthase 2 (PTGS2), hyaluronan synthase 2 (HAS-2), and gremlin-1 (GREM1), which facilitate the loosening and separation of the cumulus-oocyte complex from the follicular wall, thereby allowing its release into the peritoneal cavity, may provide insights into predicting oocyte quality. This study aims to investigate the relationship between oocyte quality and the expression levels of the PTGS2, HAS-2, and GREM1 genes in the FF of women diagnosed with EM.
Methods: In this study, we used the qRT-PCR to investigate the mRNA expression levels of PTGS2, HAS-2, and GREM1 genes in the FF of women with EM (n=23) compared to women without EM as a control group (n=23).
Results: There were no significant differences between the case and control groups regarding demographic factors such as age, body mass index (BMI), and the concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH), and anti-Mullerian hormone (AMH), all of which are known to influence oocyte quality. In addition, the statistical analysis of PTGS2 and GREM1 expression did not indicate a significant difference between the case and control groups. However, the expression level of HAS-2 was found to be significantly lower in the EM group when compared to the control group (p value= 0.0385).
Conclusion: Studies have shown a relationship between the effective expression of HAS-2 and the quality of oocytes, as well as their developmental competence. Therefore, it seems that the decrease in the expression level of this gene in the FF of women with EM is related to the decrease in oocyte quality in these patients. On the other hand, assessing the HAS-2 level seems to be an important criterion for selecting better oocytes with a higher chance of fertilization. So the expression of the HAS-2 gene can provide a new approach for predicting embryo quality and pregnancy outcome in women affected by EM.