Optimization of Endometrial Decidualization in the Menstruating Mouse Model for Preclinical Endometriosis Research

Abstract

Methods using laparoscopic and laparotomic intrauterine oil injection resulted in a higher amount of decidualized endometrium compared to sham injection, although further optimization is needed to reach full bicornuate decidualization.

Mimicking Sampson’s Retrograde Menstrual Theory in Rats: A New Rat Model for Ongoing Endometriosis-Associated Pain

“…As the morphologic changes upon decidualization are evident, the uterine weight is regarded as a relevant marker to evaluate the decidualization process. Indeed, MRM was able to increase the uterine weight of a stimulated horn by four-fold compared to the control horn, which is in line with previous murine reports [12,18,19]. Likewise, the endometrial surface increased over 10-fold compared to the control.…”

“…In addition, the stromal compartment of the decidualized horn showed positivity for desmin, confirming the differentiation of the endometrial stromal cells into decidual cells [20]. The success rate of the MRM to induce decidualization in rats, i.e., 84.5%, is also comparable to other studies, as these describe signs of decidualization in 70% to 100% of the treated animals [18,19,21]. Additionally, 22.2% of the treated horns showed a partial or uneven decidualization process, which is again in consonance with literature and can be attributed to the dynamic nature of this reaction [19,21].…”

Organoid Models of Human Endometrial Development and Disease

“…As a matter of fact, endometrium decidualization in mice and humans are quite different. Decidualization of the endometrium occurs in rodents exclusively when there is an incoming embryo or in response to mechanical injury, whereas in humans the endometrium undergoes decidualization in a cyclic manner, regardless of the presence of an embryo (Gellersen et al, 2007;Peterse et al, 2018). Therefore, findings obtained with these animals often cannot be directly translated to humans.…”

A Deeper Look Into the Decidualization of Human Endometrial Stromal Fibroblasts

“…This process, which is characterized by the differentiation of endometrial stromal fibroblasts into decidual stromal cells, entails considerable transcriptional and cellular remodeling that ultimately either enables implantation of the blastocyst and supports the early steps of pregnancy or leads to the menstruation associated cyclic renewal of the endometrium. 1,2 The process of decidualization has been widely studied [3][4][5][6][7][8] ; however, genome-wide transcriptomic changes have mainly concentrated on the early phase and some evidence suggests that decidualization may, in fact, consist of 2 differently characterized phases, an early pro-inflammatory phase of up to 3 days followed by a late secretory phase starting before day 8. Furthermore, cytokines in the early decidualization phase rather than in the late phase induce a specific secretory response from human blastocysts, suggesting that decidual stromal cells likely assume distinct states that are important to implantation and later consolidation of the fetal-maternal interface.…”

“…The process of decidualization has been widely studied 3 –8 ; however, genome-wide transcriptomic changes have mainly concentrated on the early phase and some evidence suggests that decidualization may, in fact, consist of 2 differently characterized phases, an early pro-inflammatory phase of up to 3 days followed by a late secretory phase starting before day 8. Furthermore, cytokines in the early decidualization phase rather than in the late phase induce a specific secretory response from human blastocysts, suggesting that decidual stromal cells likely assume distinct states that are important to implantation and later consolidation of the fetal–maternal interface.…”