Use of granulocyte colony-stimulating factor for the treatment of thin endometrium in experimental rats

The therapeutic effects and optimal timing of granulocyte colony stimulating factor intrauterine administration during IVF-ET

Most of embryos fail to produce live offspring during In Vitro Fertilization-Embryo Transfer (IVF-ET) procedure. There is a dearth of research activity addressing this problem despite the significant population of women suffering from repeated implantation failure after transfer of high-quality of embryos. As a clinically accessible option, granulocyte colony stimulating factor (G-CSF) is often used for the treatment to improve the rates of embryo implantation. However, there are currently no evidence-based standardized protocol for the clinical use of G-CSF. G-CSF was administered into one side of mouse uterine horns and saline was infused into the other side of horns as a control. Intrauterine G-CSF administration showed maximal effects 24 h after administration in enhancing endometrial receptivity and subsequent increase of angiogenesis by demonstrating elevated integrin β3 and OPN and reduced cytotoxicity of NK cells. Furthermore, G-CSF administration 24 h prior to embryo transfer promoted the stability of attached embryos at the early stage of implantation in vitro. Our findings suggest as new consensus criteria providing a potential therapeutic strategy of the clinical use of G-CSF to achieve maximal effects of IVF-ET for patients who are suffering from repeated implantation failure with the problems with endometrial receptivity.

Chinese medicine Yangmo decoction ameliorates intrauterine adhesion prognosis following hysteroscopic adhesiolysis

OBJECTIVES

Hysteroscopic adhesiolysis (HA) remains the mainstay on treatment for intrauterine adhesions (IUA). The fertility outcome of patients with moderate and severe intrauterine adhesions after HA is still far from satisfactory. Estrogen combined with progesterone is the most common treatment; however, they do not help in improving the fertility rate to the maximum because of the limitations. This retrospective, non-randomized controlled study will assess the effects of traditional Chinese medicine Yangmo decoction after HA in restoration of the endometrium and improvement of the fertility rate.

METHODS

A total of 427 patients, who met the inclusion criteria, aged between 20 and 45 years and diagnosed with moderate or severe IUA underwent HA at the Third Xiangya Hospital from January to August 2021, were enrolled for this study. Participants were assigned into 2 groups: A Yangmo decoction group (n=213, patients were given Yangmo decoction consisting of Ginseng flower, Sanchi flower, Daidai flower, Snow lotus, Licorice and so on after HA), and an estrogen and progesterone group (n=214, patients were given estrogen and progesterone after HA). The following basic information was collected retrospectively for both groups, including age, parity, history of abortion, menstrual status, and times of hysteroscopic interventions. American Fertility Society (AFS) score was used by a senior surgeon and the density of opening of endometrial glands was evaluated during HA. The parameters were obtained from three-dimensional transvaginal ultrasound (3D-TVUS) preoperatively and postoperatively, to evaluate the efficacy of Yangmo decoction, estrogen, and progesterone. All patients were followed up on telephone to determine the fertility rate until 6 months from the last HA.

RESULTS

Based on the basic information collected preoperatively, there were no significant differences between the groups (all P>0.05). Postoperatively, patients in the Yangmo decoction group had a better surgical success rate with a more significant AFS reduction (P<0.001), better density of opening of endometrial glands in the uterine cavity (P<0.000 1) after HA, and a better fertility rate (40.4%) in the time of 6 months after the last HA than those of the estrogen and progesterone group.

CONCLUSIONS

Yangmo decoction has better therapeutic efficacy in the treatment of intrauterine adhesion after HA than the combined effect of estrogen and progesterone. Yangmo decoction helps restore the endometrium and improve the fertility rate, therefore, it can be adopted as a routine practice for IUA patients who have fertility requirements.

Granulocyte colony-stimulating factor in reproductive-related disease: Function, regulation and therapeutic effect

Granulocyte colony-stimulating factor (G-CSF) is one of the cytokines which plays important roles in embryo implantation and normal pregnancy. At the maternal-fetal interface, G-CSF can be synthesized by multiple cells, and participates in regulation of trophoblast development, endometrial decidualization, placental metabolism and angiogenesis. Moreover, as an important medium of intercellular communication, G-CSF has also been shown to exert key roles in crosstalk between cellular components at the maternal-fetal interface. Recently, our study demonstrated that G-CSF derived from M2 macrophage could promote trophoblasts invasion and migration through activating PI3K/AKT/Erk1/2 pathway, thereby involving in normal pregnancy program. Herein, we will summarize the role and regulation of G-CSF in normal pregnancy and reproductive-related disease, and the clinical applications of G-CSF in patients undergoing in vitro fertilization with thin endometrium, repeated implantation failure, and women suffered with recurrent spontaneous abortion.

Effect of intrauterine perfusion of granular leukocyte-colony stimulating factor on the outcome of frozen embryo transfer

BACKGROUND

Treatment of thin endometrium with granular leukocyte-colony stimulating factor (G-CSF) remains controversial.

AIM

To investigate the effect of G-CSF on the outcome of frozen embryo transfer in patients with thin endometrium.

METHODS

A retrospective propensity score matching (PSM) study was performed to assess patients administered frozen embryo transfer at the Reproductive Medicine Center of the Affiliated Drum Tower Hospital of Nanjing University Medical School, in 2012-2018. The patients were divided into G-CSF intrauterine perfusion (G-CSF) and non-G-CSF groups, and clinical pregnancy, implantation, ectopic pregnancy, and early abortion rates between the two groups were compared.

RESULTS

Before PSM, 372 cycles were enrolled, including 242 and 130 cycles in the G-CSF and non-G-CSF groups, respectively. Age (34.23 ± 5.76 vs 32.99 ± 5.59 years; P = 0.047) and the blastula/cleavage stage embryo ratio (0.68 vs 0.37; P = 0.011) were significantly elevated in the G-CSF group compared with the non-G-CSF group; however, clinical pregnancy (46.28% vs 51.54%; P = 0.371) and embryo implantation (35.21% vs 35.65%; P = 0.910) rates were similar in both groups. After PSM by age and blastula/cleavage stage embryo ratio, 244 cycles were included (122 cases each in the G-CSF and non-G-CSF groups). The clinical pregnancy (50.82 % vs 48.36%; P = 0.701) and embryo implantation (37.38% vs 34.11%; P = 0.480) remained similar in both groups.

CONCLUSION

Intrauterine infusion of G-CSF does not improve the clinical outcome of frozen embryo transfer in patients with thin endometrium.

The impact of granulocyte colony-stimulating factor (G-CSF) on thin endometrium of an animal model with rats

MATERIALS AND METHODS

After forming of the thin endometrium by uterine injection of 0.2 ml 96% ethyl alcohol to the rats, five days of subcutaneous injections of 40 μg/kg G-CSF or saline were given. Endometrial thickness, immunohistochemically expression of vascular endothelial growth factor receptor-2 (VEGF-R2), proliferative cell nuclear antigen (PCNA) and fibronectin apoptosis with TUNEL method were compared in specimens among four groups of post-model rats.

RESULTS

Endometrial thickness was significantly improved in thin but not in normal endometrium group with GCSF when compared to saline injection. Stromal and glandular epithelial expression of PCNA and pericapillary VEGF-R2 was significantly increased, and apoptosis was significantly decreased with G-CSF. Although fibronectin was also increased with G-CSF in the thin endometrium, the difference was non-significant. In further, G-CSF decreased apoptotic cells and increased expression of PCNA when compared to saline injection in normal endometrium.

CONCLUSIONS

G-CSF improves endometrial thickness, proliferation, angiogenesis and DNA fragmentation in thin endometrium.

Use of Intra-uterine Injection of Platelet-rich Plasma (PRP) for Endometrial Receptivity and Thickness: a Literature Review of the Mechanisms of Action

Endometrial receptivity and thickness play an important role in achieving a pregnancy. Intrauterine autologous platelet-rich plasma (PRP) infusion has been used in infertile women with recurrent implantation failure (RIF) and thin endometrial lining thickness (EMT). Literature search was performed in PubMed for studies including in vitro, animal, and human studies as well as in abstracts presented at national conferences. Animal studies demonstrated a decrease in the expression of inflammatory markers and fibrosis, and increased endometrial proliferation rate, increased expression of proliferative genes, and increased pregnancy rates. The in vitro studies showed that PRP was associated with increased stromal and mesenchymal cell proliferation, increased expression of regenerative enzymes, and enhancement in cell migration. In infertile women undergoing assisted reproductive technology, one randomized clinical trial showed that PRP intrauterine infusion improved EMT, implantation rate, and clinical pregnancy rate (CPR) in patients with thin EMT, while 3 other trials involving subjects with RIF showed conflicting results related to CPR. Case series and cohort studies showed conflicting results pertaining to CPR. Data to date suggest that PRP may be beneficial in improving endometrial thickness and endometrial receptivity. However, further large prospective and high-quality trials are needed to assert its effect and to identify the population of patients that would benefit the most.

Evaluation of granulocyte colony-stimulating factor on the treatment of thin endometrium during frozen-thawed embryo transfer cycles: a retrospective cohort study

The aim of this study was to evaluate the effect of granulocyte colony-stimulating factor (G-CSF) on thin endometrium (≤7 mm) in women undergoing frozen-thawed embryo transfer (FET). This retrospective cohort study includes 271 infertile patients with thin endometrium. 117 patients who received intrauterine perfusion of G-CSF before the day of administration of progesterone were defined as G-CSF group, whereas 154 patients who refused to use G-CSF treatment were defined as control group. In the G-CSF group, significantly higher endometrial thickness was observed after G-CSF perfusion (p < .001). When we divided the G-CSF group into two subgroups according to whether they conceived, the endometrial thickness increased from 6.02 ± 0.92 mm to 6.98 ± 1.20 mm in the conception group (p < .001) and from 6.21 ± 0.96 mm to 6.87 ± 1.16 mm in the non-conception group (p < .001). However, there were no significant differences between the two subgroups in respect to the endometrial thickness both before and after G-CSF perfusion. The implantation rate, hCG positive rate and clinical pregnancy rate were similar between G-CSF group and control group. Thus, our study fails to demonstrate that G-CSF has the potential to improve pregnancy outcome but has the potential to increase endometrial thickness of the women with thin endometrium in FET cycles.

Effects of human recombinant granulocyte-colony stimulating factor treatment during in vitro culture on porcine pre-implantation embryos

Granulocyte-colony stimulating factor (G-CSF), a pleiotropic cytokine, belongs to the hematopoietic growth factor family. Recent studies have reported that G-CSF is a predictive biomarker of oocyte and embryo developmental competence in humans. The aim of our study was to determine whether CSF3 and its receptor (CSF3R) were expressed in porcine maternal reproductive tissues (oviduct and uterus), cumulus cells, and embryos and to investigate the effects of human recombinant G-CSF (hrG-CSF) supplementation during in vitro culture (IVC) on the developmental competence of pre-implantation embryos. To do this, we first performed reverse-transcription polymerase chain reaction (RT-PCR). Second, we performed parthenogenetic activation (PA), in vitro fertilization (IVF), and somatic cell nuclear transfer (SCNT) to evaluate the embryonic developmental potential after hrG-CSF supplementation based on various concentrations (0 ng/mL, 10 ng/mL, 50 ng/mL, and 100 ng/mL) and durations (Un-treated, Days 0–3, Days 4–7, and Days 0–7) of IVC. Finally, we examined transcriptional levels of several marker genes in blastocysts. The results of our study showed that CSF3 transcript was present in all samples we assessed. CSF3-R was also detected, except in cumulus cells and blastocysts from PA. Furthermore, 10 ng/mL and Days 0–7 were the optimal concentration and duration for the viability of in vitro embryonic development, especially for SCNT-derived embryos. The rate of blastocyst formation and the total cell number of blastocysts were significantly enhanced, while the number and index of apoptotic nuclei were significantly decreased in optimal condition groups compared to others. Moreover, the transcriptional levels of anti-apoptotis- (BCL2), proliferation- (PCNA), and pluripotency- (POU5F1) related genes were dramatically upregulated. In conclusion, for the first time, we demonstrated that CSF3 and CSF3R were expressed in porcine reproductive organs, cells, and embryos. Additionally, we determined that hrG-CSF treatment improved porcine embryonic development capacity in vitro.

The effects and mechanisms of GM-CSF on endometrial regeneration

BACKGROUND

Endometrial injury can result in thin endometrium and subfertility. Granulocyte macrophage colony stimulating factor (GM-CSF) contributes to tissue repair, but its role in endometrial regeneration has not been investigated.

METHODS

To determine the effect of GM-CSF on endometrial regeneration, we established a mouse model of thin endometrium by uterine perfusion with 20 μL 90% ethanol. Thin endometrium in mice was featured by lowered endometrial thickness, decreased expression of Ki67 in glandular cells, and a reduced number of implantation sites. To explore the mechanism of GM-CSF on endometrial regeneration, endometrium was obtained from patients undergoing hysterectomy or hysteroscopy and endometrial biopsy. Effects of GM-CSF on primary cultured human endometrial glandular and stromal cells were examined by the 5-bromo-2'-deoxyuridine (BrdU) proliferation assay and transwell migration assay, followed by exploration of the potential signaling pathway.

RESULTS

GM-CSF intraperitoneal (i.p.) injection significantly increased endometrial thickness, expression of Ki67 in endometrial glandular cells, and the number of implantation sites. GM-CSF significantly promoted proliferation of primary human endometrial glandular cells and migration of stromal cells. GM-CSF activated p-Akt and increased expressions of p70S6K and c-Jun, which were blocked by LY294002.

CONCLUSION

We found that GM-CSF could improve endometrial regeneration, possibly through activating PI3K/Akt signaling pathway.

Ozone and pulsed electro-magnetic field therapies improve endometrial lining thickness in frozen embryo transfer cycles: Three case reports

RATIONALE

In assisted reproductive technology, a persistently thin endometrial lining represents a huge challenge during frozen embryo transfer (FET) cycles.

PATIENT CONCERNS

Three patients who had a persistently thin endometrial lining despite the use of several medical agents known to improve endometrial lining thickness.

DIAGNOSES

Infertility undergoing FET cycles.

INTERVENTIONS

A combination of transdermal and intravaginal ozone therapy along with Pulsed Electro-Magnetic Field (PEMF) therapy.

OUTCOMES

Ozone with PEMF, both of which are known to have vasodilatatory, anti-inflammatory, and anti-oxidant actions, were successful in improving the thickness of the endometrial lining in all 3 patients. Two out of 3 patients became pregnant following single embryo transfer.

LESSONS

Ozone with PEMF constitute a novel experimental approach for women with persistently thin endometrial lining undergoing FET. This novel approach needs validation by large well-designed studies.

Endometrial stem cell-derived granulocyte-colony stimulating factor attenuates endometrial fibrosis via sonic hedgehog transcriptional activator Gli2

Intrauterine adhesion (IUA) is characterized by endometrial fibrosis, which ultimately leads to menstrual abnormalities, infertility, and recurrent miscarriages. The Shh/Gli2 pathway plays a critical role in tissue fibrogenesis and regeneration; Gli2 activation induces profibrogenic effects in various tissues, such as the liver and kidney. However, the role of Gli2 in endometrial fibrosis remains unknown. The purpose of this study was to test the hypothesis that activated Gli2 promotes endometrial fibrosis. Endometrial samples from moderate and severe IUA patients exhibited significantly enhanced expression of Gli2 compared with normal endometrial samples and mild IUA samples. Transfection with overactive Gli2 plasmids induced higher fibrosis-related protein expression, while blocking Gli2 signaling with cyclopamine caused the opposite effect in endometriotic stromal cells (ESCs), including inducing cell-cycle arrest. Menstrual-derived stem cell conditioned medium (MenSCs-CM) reduced endometrial fibrosis by reducing Gli2 protein levels and causing cell-cycle arrest in ESCs through granulocyte-colony stimulating factor (G-CSF). The effect was weakened after neutralization with a G-CSF antibody. Gli2 overexpression reduced the effects of MenSC-CM and G-CSF on fibrosis and cell-cycle progression in vitro. The antifibrotic effect of G-CSF was also observed in murine model. These findings demonstrate that Gli2 signaling promotes endometrial fibrosis, and the inhibition of Gli2 through MenSCs-secreted G-CSF may be of therapeutic value for managing endometrial fibrosis.

The Effects of Subcutaneous Administration of Granulocyte Colony-Stimulating Factor on Pregnancy Outcome After Assisted Reproductive Technology: Clinical Trial

Background: Granulocyte-colony stimulating factor (G-CSF) is an innovative therapy in reproductive medicine. Although its mechanisms of action have remained unknown, G-CSF seems to be effective in the case of recurrent abortion or implantation failure and thin endometrium. Objectives: This study was conducted to investigate whether subcutaneous administration of G-CSF has any effect on pregnancy outcome after assisted reproductive technology (ART). Methods: Fifty women with male infertility factors undergoing ART treatment were enrolled and stimulated with the standard long protocol. The G-CSF group of women received one dose of subcutaneous G-CSF (Filgrastim, 300 µg/1 mL) on the day of embryo transfer and again two days later while the placebo group received normal saline. Results: Seventeen patients had a positive β-human chorionic gonadotropin concentration after embryo transfer (8 and 9 in G-CSF and placebo groups, respectively) although the difference was not statistically significant. In addition, spontaneous abortion occurred in three patients (1 patient in the G-CSF group vs. 2 patients in the placebo group). Conclusion: Overall, although G-CSF failed to affect the endometrial thickness, as well as implantation, or clinical pregnancy rates, a lower prevalence of abortion in G-CSF group may be due to the positive effect of G-CSF administration on the endometrium as compared to the placebo group.

Stem cell therapy in Asherman syndrome and thin endometrium: Stem cell- based therapy

The endometrium is one of the essential components of the uterus. The endometrium of human is a complex and dynamic tissue, which undergoes periods of growth and turn over during any menstrual cycle. Stem cells are initially undifferentiated cells that display a wide range of differentiation potential with no distinct morphological features. Stem cell therapy method recently has become a novel procedure for treatment of tissue injury and fibrosis in response to damage. Currently, there is massive interest in stem cells as a novel treatment method for regenerative medicine and more specifically for the regeneration of human endometrium disorder like Asherman syndrome (AS) and thin endometrium. AS also known as intrauterine adhesion (IUA) is a uterine disorder with the aberrant creation of adhesions within the uterus and/or cervix. Patients with IUA are significantly associated with menstrual abnormalities and suffer from pelvic pain. In addition, IUA might prevent implantation of the blastocyst, impair the blood supply to the uterus and early fetus, and finally result in the recurrent miscarriage or infertility in the AS patients. It has been evidenced that the transplantation of different stem cells with a diverse source in the endometrial zone had effects on endometrium such as declined the fibrotic area, an elevated number of glands, stimulated angiogenesis, the enhanced thickness of the endometrium, better formed tissue construction, protected gestation, and improved pregnancy rate. This study presents a summary of the investigations that indicate the key role of stem cell therapy in regeneration and renovation of defective parts.

[Efficacy of gamma-irradiated adipose-derived stem cells for treatment of thin endometrium in rats]

OBJECTIVE

Transplantation of adipose-derived stem cells (ADSCs) is associated with potential risks of late complications including tumorigenesis due to the active proliferation of the cells. We aimed to test the effect of transplantation of ADSCs with suppressed proliferation by gamma irradiation in the treatment of thin endometrium in rats.

METHODS

ADSCs were isolated from female SD rats and identified by detecting the surface antigens with flow cytometry. After exposure to gamma irradiation at 0, 5 Gy and 10 Gy, the cells were examined for changes in colony-forming ability. Twenty-four female rats with chemically induced thin endometrium were randomized into 4 equal groups and at 6-8 h after modeling, the rats received intrauterine injection of non-irradiated ADSCs (group Ⅰ), 5 Gy irradiated ADSCs (group Ⅱ), 10 Gy irradiated ADSCs (group Ⅲ), or PBS only (group Ⅳ). Endometrial pathology was analyzed with HE staining in these rats in the third estrus phase following the cell transplantation.

RESULTS

The ADSCs showed a complete loss of proliferative capacity after exposure to 10 Gy irradiation. After the cell transplantation, the endometrium thickness was thicker in group Ⅰ and Ⅱ than in group Ⅳ (P < 0.01), but there was no significant difference between groups Ⅲ and Ⅳ.

CONCLUSIONS

Gamma irradiation impairs the proliferative capacity of ADSCs in vitro. Exposure to 10 Gy irradiation causes a total loss of proliferation capacity of the ADSCs, which have no therapeutic potential; 5 Gy irradiation causes partial loss of proliferation capacity of the cells, which still retain the activity to promote endometrial cell regeneration.

The efficacy of intrauterine instillation of granulocyte colony-stimulating factor in infertile women with a thin endometrium: A pilot study

Objective

The study aimed to investigate the efficacy of intrauterine instillation of granulocyte colony-stimulating factor (G-CSF) on the day of ovulation triggering or oocyte retrieval in infertile women with a thin endometrium.

Methods

Fifty women whose endometrial thickness (EMT) was ≤8 mm at the time of triggering during at least one previous in vitro fertilization (IVF) cycle and an index IVF cycle were selected. On the day of triggering (n=12) or oocyte retrieval (n=38), 300 µg of G-CSF was instilled into the uterine cavity.

Results

In the 50 index IVF cycles, the mean EMT was 7.2±0.6 mm on the triggering day and increased to 8.5±1.5 mm on the embryo transfer day (p<0.001). The overall clinical pregnancy rate was 22.0%, the implantation rate was 15.9%, and the ongoing pregnancy rate was 20%. The clinical pregnancy rate (41.7% vs. 15.8%), the implantation rate (26.7% vs. 11.7%), and the ongoing pregnancy rate (41.7% vs. 13.2%) were higher when G-CSF was instilled on the triggering day than when it was instilled on the retrieval day, although this tendency was likewise not statistically significant. Aspects of the stimulation process and mean changes in EMT were similar in women who became pregnant and women who did not.

Conclusion

Intrauterine instillation of G-CSF enhanced endometrial development and resulted in an acceptable pregnancy rate. Instillation of G-CSF on the triggering day showed better outcomes. G-CSF instillation should be considered as a strategy for inducing endometrial growth and good pregnancy results in infertile women with a thin endometrium.

Treating patients with "thin" endometrium - an ongoing challenge

OBJECTIVE

To review the literature regarding inadequate growth ("thin") of the endometrium and to present the hitherto published methods aimed to improve endometrial thickness and the consequent endometrial receptivity.

MATERIALS AND METHODS

A literature review was conducted for all relevant articles assessing the effect of various treatment modalities on "thin" endometrium and the consequent reproductive outcome.

RESULTS

Several treatment modalities have been offered to patients with "thin" endometrium, including hysteroscopic adhesiolysis, hormonal manipulation by estrogen and GnRH-agonist, vasoactive measures such as aspirin, vitamin E, pentoxifylline, l-arginine or sildenafil, intra-uterine infusion of growth factor such as G-CSF and the recent application of regenerative medicine. In spite of the vast diversity of treatment, most of the options accomplish only minor change in the endometrium thickness and subsequent pregnancy rate, and when they fail, patients are usually referred to surrogacy.

CONCLUSIONS

"Thin" endometrium is known to adversely affect reproductive performance. Treatment of "thin endometrium" remains a challenge and future large researches are required to further elucidate and optimal management of patients with "thin" endometrium.