| The endometrium of patients with PCOS is insensitive to estrogen or progestin after long-time exposure to low estrogen> which may affect blastocyst implantation. High ovulation rate but low pregnancy rate will be found in PCOS during controlled ovarian hyperstimulation, of which that reduced response of endometrium to blastocyst may be in charge. Some of them have to turn to IVF or IVM when failing to conceive a child after all kinds of therapies for infertility. Cryopreservation of embryos for future transfer in an artificial cycle has been an effective alternative for patients with PCOS when they have excess embryos during IVF/IVM or they are in high risk of OHSS during IVF. How to apply appropriate estrogen and progestin to prepare endometrium for better receptivity remains elusive.Integrins are a family of heterodimeric transmembrane glycoproteins that participate in diverse cell-to-cell and cell-to-extracellular matrix interactions. The extracellular domain can act as a receptor for extracellular matrix components, adhesion molecules of other cells, or signaling proteins. The patterns of integrin expression in human endometrium exhibit cycle-dependent expression with temporal characteristics. Integrin v 3 appears in endometrium postovulatory day 5-6, corresponding to the time of embryo attachment, and has been generally accepted as a marker of endometrialreceptivity. Reduced mid-luteal v s expression has been reported in connection with luteal phase deficiency (LPD), minimal or mild endometriosis, communicating hydrosalpinx and unexplained infertility. Integrin v 3 appears to be an excellent marker to study the molecular events leading to the establishment of uterine receptivity and successful implantation.The MMPs form a family of structurally related, zinc-dependent endopeptidases that are involved in the degradation of the extracellular matrix (ECM) and basement membranes (BM). TIMPs, are the natural inhibitors of all MMPs, which bind with high affinity and 1:1 molar ratio to MMPs and regulate the activity of proteinases. MMPs, together with their inhibitor TIMPs, play a critical role in normal tissue-remodeling processes, including embryonic growth, development and implantation.Among MMPs, the 92-Kda type IV collagenase (MMP-9) is a very important enzymes for BM degradation, capable of degrading virtually all components of the ECM, such as collagens, proteoglycans, and glycoproteins, particularly collagen type IV and V. TIMP-1 is the main inhibitor of MMP-9. Many studies have found the focal staining of MMP-9 and TIMP-1 in glandular epithelial cells of mid-luteal endometrium, which suggest that these enzymes might contribute to blastocyst implantation. To date, integrin avp3, MMP-9 and TIMP-1 as markers to evaluate the endometrial function of patients with PCOS in artificial hormonal cycles has not been reported. Little has been reported about the association of MMP-9 and integrin avp3. The purpose of this study was to investigate the effect of hormonal replacement on expression of integrin avp3, MMP-9 and TIMP-1 in endometrium and to assess whether hormonal replacement can improve the endometrial receptivity in PCOS. Also we analysed the association of MMP-9 and integrin avp3 to further provide the rationale of MMP-9 as a marker of endometrial receptivity.41 PCOS patients who hadn't received hormonal therapy for three months were designated to study group, then randomly divided into two groups: group A and group B. Group A: Daily i.m. progesterone-in-oil injections were administered in a dose of 20 mg for 10 days. Group B: 20mg i.m. progesterone-in-oil were injected for ten days. At the day 5 of withdrawal bleeding, Img progynova was administered for 20 days. 20 mg progesterone-in-oil injections were added following 10 days of progynova. These patients underwent endometrial biopsies and serum collection 7 after progesterone injection. Fourteen women with normal fertility were selected as controls, andunderwent endometrial biopsies and serum collection 7* after the onset of...
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