Emerging role of embryo secretome in the paracrine communication at the implantation site: a proof of concept.

OBJECTIVE: To assess the role of embryo secretome in modifying the molecular profile of glycodelin A (GdA) in endometrial organoids (ORG) mimicking the implantation window. To verify whether the use of embryo-conditioned culture medium at the time of the embryo transfer may increase in vitro fertilization outcome. DESIGN: Molecular study with human endometrial ORG and embryo-conditioned culture medium. Retrospective study using prospectively recorded data. SETTING: University hospital. PATIENT(S): For isolation and culture of endometrial glandular ORG, endometrial biopsy specimens from five white women of proven fertility undergoing laparoscopy for tubal sterilization. A total of 75 women undergoing intracytoplasmic sperm injection for tubal and/or male infertility factor. INTERVENTIONS(S): In vitro fertilization. MAIN OUTCOME MEASURE(S): Pinopodes presence in human endometrial ORG. Glycodelin A expression profile by means of two-dimensional electrophoresis. In vitro fertilization outcome. RESULT(S): This in vitro study demonstrated that the treatment of endometrial ORG with the secretome of medium conditioned by the growing embryo increased the GdA relative abundance and induced a different glycoform pattern. Biochemical and clinical pregnancy rate significantly increased when the spent medium was loaded during the transfer (17.5% vs. 36.6% and 16.5% vs. 35.1%, respectively). CONCLUSION(S): This study demonstrated that the secretome of implanting embryos is able to induce the expression as well as to determine the relative abundance and the glycosilation profile of endometrial GdA, a protein having a key role in the embryo-endometrial cross talk. Moreover, a significant increase in pregnancy rate was observed when the embryo transfer was performed by using the culture medium conditioned by the growing embryo.

Increased expression of neurogenic factors in uterine fibroids.

STUDY QUESTION: Are selective markers for the neuronal differentiation such as microtubule-associated protein 2 (MAP-2) and synaptophysin (SYP) as well as the nerve growth factor (NGF) expressed by fibroids, myometrium and eutopic endometrium? SUMMARY ANSWER: Neuronal markers NGF, MAP-2 and SYP are highly expressed in fibroids compared with matched myometrium, and this neurogenic pathway is upregulated by tumor necrosis factor (TNF) alpha in cultured smooth muscle cells (SMCs). WHAT IS KNOWN ALREADY: Uterine fibroids or leiomyomas are the most common benign tumors, accounting for approximately one-third of hysterectomies. The present trend is to improve the medical treatment avoiding surgery, also for fertility sparing; hence, the pathogenic mechanisms are investigated, aiming to develop new therapeutic strategy. STUDY DESIGN, SIZE, DURATION: This laboratory-based case-control study is focused on fibroids and myometrial specimens obtained between 2015 and 2017 from 15 women of reproductive age at the proliferative phase of the menstrual cycle. Leiomyomas, matched myometrium and endometrium from each woman were analyzed. Control endometrium was obtained from women undergoing surgery for ovarian cyst (n = 15). PARTICIPANTS/MATERIALS, SETTING, METHODS: qRT-PCR, western blotting and immunostaining were applied to evaluate the expression of neurogenic markers; the effects of TNF on NGF, MAP-2 and SYP expression in cultured SMCs from leiomyomas and matched myometrium were analyzed. MAIN RESULTS AND THE ROLE OF CHANCE: qRT-PCR analyses using tissues from clinical patients showed that the levels of NGF, MAP-2 and SYP mRNA were significantly higher in uterine leiomyomas compared with their matched myometrium (P < 0.05), whereas only NGF was significantly increased in eutopic endometrium compared with healthy endometrium. In primary SMCs, isolated from fibroids or from the adjacent myometrium, NGF, MAP-2 and SYP mRNA expression were significantly increased by TNF treatment (P < 0.05). Finally, human endometrial stromal cells prepared from the endometrium of patients affected by uterine fibroids display higher TNF expression (P < 0.001). LIMITATIONS, REASONS FOR CAUTION: qRT-PCR analysis and immunofluorescence validation are robust methods demonstrating a clear upregulation of neurogenic factors in leiomyomas, even though additional studies are needed to establish a correlation between increased neuronal gene expression and degree of pain, as well as the involvement of inflammation mediators in the development of the neurogenic unhinge. Therefore, more in vivo studies are needed to confirm the results achieved from primary cultured SMCs. WIDER IMPLICATIONS OF THE FINDINGS: The increased expression of neurogenic factors in uterine fibroids and endometrium may contribute to explain the painful stimuli. Accordingly, these neurogenic pathways may represent potential therapeutic avenues to treat the fibroid-related disorders. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by research grants from the University of Siena. The authors declare no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.

Dysregulation of GdA Expression in Endometrium of Women With Endometriosis: Implication for Endometrial Receptivity.

Glycodelin-A (GdA) has been proposed to represent a potential biomarker of endometrial function, but little is known about its expression during the different phases of the menstrual cycle and under pathological conditions. In the light of its potential importance also in embryo implantation, we aimed to evaluate the expression profile of GdA as well as the presence of different glycosylated glycoforms and the immunolocalization in endometrial tissue from women with endometriosis and in women with proven fertility, at different times during the menstrual cycle. Our results showed that GdA is synthesized by endometrial epithelial and stromal cells, both in healthy endometrium and eutopic endometrium from women with endometriosis, with a profile including several glycosylated glycoforms, differentially expressed in each phase of the menstrual cycle. During the secretory phase, a significant increase in GdA protein expression, with a different glycoforms profile, was observed in endometriotic eutopic endometrium. Protein localization in eutopic endometrial tissue resulted significantly different in comparison with endometrium from women with proven fertility. This study indicate that GdA is a complex glycoprotein including up to 6 different glycoforms specifically expressed during the different phase of the menstrual cycle; in pathologic conditions such as endometriosis, the expression profile is altered possibly related to the impaired endometrial receptivity.