Loading color scheme

Distinction with the young investigation award for the research team of prof. Eva Kassi department of biological chemistry shool of medicine nkua by european society of endocrinology

Press release –Abstract: Alterations in clock genes expression in Eutopic and Ectopic Endometrial Tissue

New research suggests that night shift work is linked to menstrual irregularity and increased chance of developing endometriosis.

According to a study being presented at e-ECE2021, women working night shifts may be at a greater risk of menstrual irregularity and developing endometriosis. The research found a reduction in the expression of PER-2, CRY-1 and CLOCK genes along with an increase in REV-ERBb in ectopic compared to eutopic tissues. Prior to this research, there have been no previously published studies relating to the alterations in core clock-genes and the impact on women with endometriosis.

Endometriosis is a condition where tissue similar to the lining of the womb starts to grow in other places such as ovaries and fallopian tubes. Endometriosis affects roughly 10% (190 million) of reproductive age women and girls globally. The symptoms of endometriosis can vary - some women are badly affected, while others might not have any noticeable symptoms. In severe cases, it can be very painful and can cause infertility, miscarriages and ectopic pregnancies due to the probable effects of endometriosis on the pelvic cavity, ovaries, fallopian tubes, or uterus.2 Disruption of circadian rhythm in night shift workers has been associated with menstrual irregularity, as well as an increased chance of developing endometriosis and ovarian tumours.

Dr. Narjes Nasiri-Ansari, Aggeliki Karapanagioti, and a team of colleagues under the guidance and supervision of Professor Eva Kassi from the Department of Biological Chemistry, School of Medicine, National and Kapodistrian University of Athens investigated the expression of the core clock related genes in paired eutopic and ectopic endometrial tissues. The study looked at 27 patients with confirmed ovarian endometriosis. 11 paired samples were collected from ovarian cysts (ectopic endometrial tissues) and normal endometrium (eutopic tissues), while further 8 ectopic and 8 eutopic endometrial tissues were collected from 16 different patients with the same diagnosis.

“The clinical evidence that circadian rhythm disruptions can be associated with endometriosis, is now confirmed at tissue level, by the altered expression of local clock genes in ectopic endometrium.  Understanding the causes and effects of endometriosis will improve our ability to detect, manage or even prevent the condition. These findings provide us with a better understanding of biological rhythm disturbances” commented Eva Kassi.

The study results demonstrate an altered expression of CLOCK, CRY1, PER-2 and Rev-ERBb in normal endometrium tissues, as compared to ectopic endometrial tissues, indicating a disturbance of local circadian rythms. It has been shown that peripheral clock system through its clock proteins can regulate inflammatory-associated cytokines and other processes (i.e. angiogenesis) which are known  to be involved  in the immune-dysfunctions in the peritoneal niche and the endometriosis-associated infertility. More interestingly, the study results show an increased expression of GRα in ectopic compared to eutopic endometrium, indicating a possible involvement of cortisol in the disruption of the peripheral clock genes in ectopic endometrium.

However, the causal relationship of the altered expression pattern of these genes with the development of endometriosis needs further investigation.