Adipose-Derived Stromal Vascular Fraction Cell Effects on a Rodent Model of Thin Endometrium

The Effects of Filgrastim and Hyaluronic Acid on the Endometrium in Experimentally Induced Asherman Syndrome Rat Models: A Prospective Laboratory Study

Background/Objectives: The aim of the present study was to explore the histopathological effects and tissue Vascular Endothelial Growth Factor (VEGF) levels of filgrastim and hyaluronic acid treatment in a rat model with experimentally induced Asherman syndrome. Methods: In this study, 26 female Sprague Dawley rats were used. First, a rat model of Asherman syndrome was established in two rats, and the remaining rats were randomly divided into three groups. A total of 0.1 mL trichloroacetic acid was applied to the right uterine horns of all groups to induce adhesion formation.Group I received no treatment, Group II received intrauterine hyaluronic acid treatment (0.01), Group III received subcutaneous Filgrastim treatment (50 μg/kg/day), and Group IV received both intrauterine hyaluronic acid and subcutaneous Filgrastim treatment. Histopathological analysis of uterine horns in the rats with and without Asherman syndrome, inflammation, glandular count, and fibrosis levels were examined. Tissue VEGF levels were investigated immunohistochemically. Results: Hyaluronic acid treatment resulted in an increase only in uterine lumen diameter and VEGF levels, while Filgrastim treatment led to an increase in uterine wall diameter, lumen diameter, gland count, and VEGF levels, as well as a decrease in fibrosis and inflammation scores. Combined treatment with filgrastim and hyaluronic acid showed an increase in lumen diameter, gland count, and VEGF levels, along with a decrease in inflammation and fibrosis scores (p < 0.05). Filgrastim treatment resulted in better effects for Asherman syndrome compared to hyaluronic acid treatment. There were no beneficial effects seen with the combined therapy. Conclusions: Filgrastim treatment resulted in better outcomes for Asherman syndrome compared to hyaluronic acid treatment. The combined therapy did not show additional benefits beyond what was achieved with Filgrastim treatment alone.

The Effects of Methylprednisolone and Hyaluronic Acid on the Endometrium in Experimentally Induced Asherman Syndrome Rat Models: A Prospective Laboratory Study

Background and Objectives: The current study was designed as a prospective laboratory investigation to evaluate the histopathological effects and VEGF (vascular endothelial growth factor) expression in uterine tissue following treatment with a combination of methylprednisolone and hyaluronic acid in a rat model of experimentally induced Asherman Syndrome. Materials and Methods: Twenty-six female Sprague-Dawley rats were used. Trichloroacetic acid was applied to the right uterine horns of all the groups to induce adhesion formation. First, we induced the Asherman model in two rats (Group 1). The remaining rats were divided into the following three groups: Group 2 received intrauterine hyaluronic acid treatment, Group 3 received oral methylprednisolone treatment, and Group 4 received both treatments. Inflammation, gland count, and fibrosis levels were assessed histopathologically. VEGF levels were analyzed immunohistochemically. Results: Hyaluronic acid treatment increased the uterine lumen diameter and vascularization. Methylprednisolone treatment increased the gland count and uterine wall thickness while decreasing the inflammation and fibrosis scores. Combined treatment provided a statistically significant advantage over single treatments. In particular, the combined treatment group exhibited significantly lower fibrosis (p = 0.184) and inflammation scores (p = 0.071), as well as higher gland counts (p = 0.849) and VEGF expression (p = 0.114), compared to the groups receiving only methylprednisolone or hyaluronic acid. These differences indicate that the synergistic effect of the two agents results in more effective endometrial healing than when either treatment is applied alone. Conclusions: Methylprednisolone treatment significantly prevented adhesion formation and reduced the inflammation and fibrosis scores compared to hyaluronic acid treatment alone. The combined treatment adds to the effects of the hyaluronic acid treatment alone and provides better healing.

Stromal vascular fraction: Mechanisms and application in reproductive disorders

Stromal vascular fraction (SVF) is a complex mixture derived from adipose tissue, consisting of a variety of cells. Due to its potential for tissue repair, immunomodulation, and support of angiogenesis, SVF represents a promising frontier in regenerative medicine and offers potential therapy for a range of disease conditions. In this article, we delve into the mechanisms through which SVF exerts its effects and explore its potential applications in treating both male and female reproductive disorders, including erectile dysfunction, testicular injury, stress urinary incontinence and intrauterine adhesion.

Intrauterine injection of bioengineered hydrogel loaded exosomes derived from HUCM stem cells and spermidine prominently augments the pregnancy rate in thin endometrium rats

The endometrium is essential to the development of embryos and pregnancy. Human umbilical cord mesenchymal stem cells (HUCMSCs) are promising stem cell sources. HUCMSCs self-renew quickly and are painless to collect. Spermidine is an inherent polyamine needed for cellular and molecular processes that regulate physiology and function. HUCMSCs and spermidine (SN) may heal intrauterine adhesions. HUCMSCs were investigated for endometrial repair in rats. Composite hydrogels are used for medical exosome implantation, including their materials, properties, and embedding procedures. This study examined whether bioengineered hydrogel-loaded exosomes from HUCMSCs and spermidine prenatally improved conception rates in mice with poor endometrial lining. The data show that HUCMSC and SN provide a good experimental base for HUCMSC safety and intrauterine treatment in rats. Western blots, exosome structural analysis, pregnancy outcomes, flow cytometry, H&E staining, immunohistochemistry, and immunofluorescence labelling found and recovered the aberrant area. HUCM-derived stem cells and spermidine-derived exosomes biophysically match. These traits strengthen and prolong endometrial function. Pregnant rats with HUCMSC and SN had thinner endometrium. Hydrogel-incorporated HEHUCMSC and SN exosomes may improve IUI in rats with thin endometrium.

Effect of collagen endometrial patch loaded with adipose-derived mesenchymal stem cells on endometrial regeneration in rats with a thin endometrium

Background

This study aimed to investigate the effects of a collagen endometrial patch (EM patch) loaded with adipose-derived mesenchymal stem cells (ADSCs) on endometrial regeneration in a rat model with thin endometrium.

Materials and methods

Thin endometrium was induced in female rats and divided into treatment groups as outlined: control, group 1(G1), local injection of ADSCs into the uterus, group 2 (G2), an EM patch without ADSCs, group 3 (G3), and an EM patch loaded with ADSCs, group 4 (G4). The rats were euthanized at either two weeks or four weeks after modeling and treatment followed by histological and biochemical analyses to examine the regenerative effects on the injured endometrium.

Results

Transplantation of the ADSC-loaded EM patch significantly promoted endometrial proliferation and increased the luminal epithelial area. Two weeks after treatment, the mean number of von Villebrand factor (vWF)+ or cluster of differentiation (CD) 31+-stained blood vessels was significantly higher in G4 than in G1 and G2. The mRNA and protein expression levels of TGF-β and FGF2 were significantly upregulated in G4 compared to those in the control. G4 exhibited significantly increased LIF mRNA levels and immunoreactivity compared with the other groups at both two weeks and four weeks after treatment. Cell tracking after ADSCs treatment revealed the presence of a substantial number of ADSCs grafted in the uterine tissues of G4, whereas a low number of ADSCs that were focally clustered were present in G2.

Conclusion

Transplantation of EM patches loaded with ADSCs resulted in the histological and biochemical restoration of an injured endometrium. The strategic integration of EM patches and ADSCs holds significant promise as an innovative therapeutic approach for effectively treating impaired endometrial conditions.

Efficacy and safety of autologous adipose tissue-derived stromal vascular fraction in patients with thin endometrium: a protocol for a single-centre, longitudinal, prospective self-control study

INTRODUCTION

Endometrial thickness is an important parameter to evaluate endometrial receptivity. An appropriate endometrial thickness is necessary for both embryo implantation and maintaining normal pregnancy. Women with thin endometrium are one of the critical challenges in the clinic, and current therapeutic strategies for thin endometrium remain suboptimal. The stromal vascular fraction (SVF) derived from adipose tissue contains a variety of cells, mainly adipose-derived stem/stromal cells and adipose cells. Recently, adipose tissue-derived SVF showed tremendous potential for treating thin endometrium due to its capacity to repair and regenerate tissues. The application of SVF in animal models for treating thin endometrium has been investigated. However, limited evidence has demonstrated the efficacy and safety of autologous SVF in patients with thin endometrium.

METHODS AND ANALYSIS

This study is a single-centre, longitudinal, prospective self-control study to investigate the preliminary efficacy and safety of autologous SVF in improving the pregnancy outcome of infertile patients with thin endometrium. Thirty patients diagnosed with thin endometrium will be recruited based on the inclusion and exclusion criteria. The SVF suspension will be transferred into the uterine cavity via an embryo transfer catheter. Then, comparisons between pretreatment and post-treatment will be analysed, and the outcomes, including endometrial thickness, menstrual volume and duration, frequency and severity of adverse events and early pregnancy outcomes, will be measured within a 3-month follow-up, while late pregnancy outcomes and their offspring will be followed up via telephone for 2 years. The proportion of patients with improved symptoms will be calculated and compared.

ETHICS AND DISSEMINATION

This study was approved by the Ethics Committee of Peking University Third Hospital (reference number: REC2020-165). Written informed consent will be provided for patients before being included. The results will be presented at academic conferences and a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ChiCTR2000035126.

Transplantation of Human Adipose Stem Cells Using Acellular Human Amniotic Membrane Improves Angiogenesis in Injured Endometrial Tissue in a Rat Intrauterine Adhesion Model

Endometrial injury resulting in intrauterine adhesion is associated with extensive damage to the regenerative basal layer of the endometrium and represents a major therapeutic challenge. Human adipose stem cells (hASCs) hold promise for future clinical use in the individualized therapy of injured endometrial tissue. Here, we observed that the use of the acellular human amniotic membrane (AHAM) significantly increased the expression of angiogenic factors, including angiogenin (ANG) and vascular endothelial growth factor (VEGF), in hASCs in vitro. The three-dimensional engineered hASC-AHAM grafts significantly increased the endometrial receptivity, as increased endometrial thickness, greater numbers of endometrial glands, and higher protein levels of leukemia inhibitory factor were observed in injured endometrial tissue that was treated with these grafts compared to those detected in injured endometrial tissue that was treated with AHAM alone. In addition, the hASC-AHAM grafts significantly increased the vascular density in the injured endometrial tissue in rats, when transplanted into an injured uterine cavity. Using the EGFP⁺-hASC-AHAM grafts for transplantation, we confirmed that the hASCs maintained higher protein levels of ANG and VEGF in the injured uterine cavity in vivo. The results of this study suggest that the ability of the engineered hASC-AHAM grafts to repair injured endometrial tissue may be associated with their ability to promote angiogenesis through the upregulated expression of angiogenic factors in hASCs. These findings may support individualized stem cell–based therapy for endometrial disease using bioartificial grafts.

Will stem cells from fat and growth factors from blood bring new hope to female patients with reproductive disorders?

Female reproductive system disorders (FRSD) with or without infertility are prevalent women's health problems with a variety of treatment approaches including surgery and hormone therapy. It currently considering to sub-branch of regenerative medicine including stem cells or growth factors injection-based delivery treatment might be improved female reproductive health life. The most common products used for these patients treatment are autologous cell or platelet-based products from patients, including platelet-rich plasma, plasma rich in growth factor, platelet-rich fibrin, and stromal vascular fraction. In this review, we discuss each of the above products used in treatment of FRSD and critically evaluate the clinical outcome.

Effect of Bushen Yutai Recipe on IVF Patients Subjected to Mild Ovarian Stimulation

This article investigated the effects of the traditional Chinese medicine (TCM) herbal recipe, Bushen Yutai, on in vitro fertilization (IVF) patients subjected to mild ovarian stimulation. Two hundred nineteen infertile patients were randomly divided into 2 groups: the control group and herbal treatment group. By studying, we found estrogen levels (E₂) on the human chorionic gonadotropin (hCG) triggering day were significantly lower in the control group (P < 0.05), with positive blood flow being less detected by ultrasound scanning on both the day of hCG triggering and day of fresh embryo transfer for the control group (P < 0.05). Additionally, the blood flow index, retroactive and proactive inhibition, was higher in the control group, whereas the fertilization rate and number of high-quality embryos in the control group were lower than the control TCM experimental group (P < 0.01). The expression levels of the endometrial receptivity gene, vascular endothelial growth factor (VEGF), were lower in the control group vs. the TCM experimental group on the day of fresh embryo transfer (P < 0.05), whereas the rate of fresh embryo transfer in the control group was lower than the TCM experimental group (P < 0.05). In conclusion, the TCM could increase the E₂ during the IVF stage, with a higher number of oocytes and higher-quality embryos. It also improved the endometrium and increased the level of VEGF gene expression. By enhancing the fresh embryo transfer rate in a minimal ovarian stimulation protocol and by improving the clinical pregnancy and ongoing pregnancy rates, the Bushen Yutai recipe could be able to increase fresh embryo transfer and higher-quality embryos.

Adipose tissue-derived regenerative cells improve implantation of fertilized eggs in thin endometrium

Aim: Embryo implantation and subsequent pregnancy depends on endometrial thickness. To investigate potential fertility strategies for women with thin endometrium, we explored the efficacy of adipose tissue-derived regenerative cells (ADRCs) on thin endometrium and embryo implantation in a mouse model. Materials & methods: ADRCs isolated from mouse subcutaneous fat were characterized by flow cytometry. Endometrium thickness, endometrial fibrosis, embryo implantation and angiogenesis factors were evaluated in uterine cavities of ethanol-induced thin endometrium mice with ADRC transplantation. Results: ADRCs included adipose-derived stem cells and some blood vessel component cells. ADRCs improved endometrial thickness, endometrial fibrosis and embryo implantation and augmented vascular endothelial growth factor expression in the mouse uterine. Conclusion: ADRCs may be a useful therapeutic strategy to improve fertility of women with thin endometrium.

Exosomes Derived from Adipose Mesenchymal Stem Cells Restore Functional Endometrium in a Rat Model of Intrauterine Adhesions

Intrauterine adhesion (IUA) caused by endometrial injury is one of the important causes of infertility in women of reproductive age and requires advanced treatment strategies. Increasing evidence suggests that the therapeutic effects of mesenchymal stem cells (MSC) mainly depend on their capacity to secrete paracrine factors and are mediated by MSC-derived exosomes. This study aimed to identify exosomes derived from adipose-derived mesenchymal stem cells (ADSC-exo) and explore the therapeutic potential in IUA rat models. ADSC-exo exhibited classic cup-shaped morphology with a positive expression of Alix and CD63 and were mainly concentrated at 109.5 nm. In IUA model, treatment with ADSC-exo maintained normal uterine structure, promoted endometrial regeneration and collagen remodeling, and enhanced the expression of integrin-β3, LIF, and VEGF. An improved receptivity of the regenerated endometrium was confirmed. Our findings demonstrated that ADSC-exo promoted endometrial regeneration and fertility restoration. It suggested that topical administration of ADSC-exo in uterus could be a promising strategy for patients suffering severe intrauterine adhesions and infertility.

Effect of Autologous Adipose-Derived Stromal Vascular Fraction Transplantation on Endometrial Regeneration in Patients of Asherman's Syndrome: a Pilot Study

This study aimed to investigate the efficacy of the transplantation of autologous adipose-derived stromal vascular fraction (AD-SVF) containing adipose stem cells (ASCs) in regenerating functional endometrium in patients with severe Asherman's syndrome (AS). This was a prospective clinical study involving six infertile women aged 20-44 years who were diagnosed with severe AS by hysteroscopy. Autologous AD-SVF were isolated from patient's adipose tissue obtained by liposuction and then transplanted into uterus by transcervical instillation using an embryo transfer catheter followed by estrogen hormone therapy. Endometrial growth and pregnancy outcomes were assessed after fresh or frozen embryo transfer. Of the five patients who remained in the study, two women who had amenorrhea resumed their menstruation with irregular scant bleeding. Three women with oligomenorrhea had increased menstrual amount. Before therapy, the maximum EMT measured ultrasonographically was 3.0 ± 1.0 mm (range: 1.7 to 4.4 mm), which significantly increased to 6.9 ± 2.9 mm (range: 5.2 to 12.0 mm, p = 0.043) after cell transplantation and hormone therapy. Five women had embryo transfer after therapy: one fresh and four frozen-thawed. One woman conceived but aborted spontaneously at 9-week gestation. AD-SVF is a safe and easily available cell product containing adipose-derived stem cells. Autologous transplantation of AD-SVF may regenerate damaged human endometrium and increase endometrial receptivity. Our study showed the feasibility of AD-SVF in restoring endometrial function and increasing endometrial thickness. This cell therapy may become a promising treatment for infertile women with endometrial dysfunction and needs further investigation.

The ameliorating effects of Bushen Tiaoxue Granules and Kunling Wan on impaired angiogenesis and endometrial receptivity in rats following controlled ovarian hyperstimulation

OBJECTIVE

To investigate the effects of Bushen Tiaoxue Granules and Kunling Wan, the two Chinese medicines, on vascular dysfunction and the impairment of endometrial receptivity caused by controlled ovarian hyperstimulation and its underlying mechanism.

METHODS

Female Sprague Dawley rats with regular estrous cycle were enrolled and given Bushen Tiaoxue Granules or Kunling Wan by gavage for 12 days, and then, controlled ovarian hyperstimulation model was induced. We assessed endometrial microvessels, endometrial blood flow, levels of estradiol and progesterone in serum, vascular endothelial growth factor A upstream molecules estrogen and progesterone receptors in the endometrium, and pregnancy outcome.

RESULTS

Pre-treatment of Bushen Tiaoxue Granules or Kunling Wan increases endometrial blood flow of controlled ovarian hyperstimulation rats, up-regulates vascular endothelial growth factor A and microvessels, improves the endometrial morphology of controlled ovarian hyperstimulation rats during implantation, decreases the super physiological concentration of estradiol and progesterone in serum, and increases the expression of vascular endothelial growth factor A upstream molecules estrogen and progesterone receptors in the endometrium. In addition, Bushen Tiaoxue Granules or Kunling Wan elevates the lysophosphatidic acid receptor 3 that participates in vascularization and increases the expression of leukemia inhibitory factor through up-regulating the expression of p53 in the endometrium, ultimately affecting pregnancy outcome.

CONCLUSION

This study demonstrated Bushen Tiaoxue Granules or Kunling Wan as a potential strategy for prevention of impairment in angiogenesis and endometrial receptivity induced by controlled ovarian hyperstimulation.

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.

Abnormal expression of fibrosis markers, estrogen receptor α and stromal derived factor‑1/chemokine (C‑X‑C motif) receptor‑4 axis in intrauterine adhesions

Intrauterine adhesions (IUAs) are mainly derived from fibrous tissue formation following endometrial damage. The aim of the present study was to assess whether fibrosis markers, estrogen receptor (ER)α and the stromal derived factor (SDF)-1/C-X-C chemokine receptor type 4 (CXCR-4) axis are abnormally expressed in IUA endometrium. A total of 76 human endometrial biopsy samples (normal, n=20; mild-to-moderate IUAs, n=40; and severe IUAs, n=16) were employed, and Sprague-Dawley rat IUA models at different time points were constructed. Subsequently, the expression of transforming growth factor (TGF)-β1, matrix metalloproteinase (MMP)-9, ERα and the SDF-1/CXCR-4 axis was evaluated in human and rat IUAs using histology, immunohistochemistry, reverse transcription quantitative polymerase chain reaction and western blotting. In patients and rats with IUA formation, the expression of TGF-β1, MMP-9 and ERα was significantly higher compared with the control group at the mRNA and protein levels (P<0.05); in addition, in patients, the TGF-β1, MMP-9 and ERα levels were significantly higher in severe IUAs compared with those in mild-to-moderate IUA endometrium (P<0.05). Although the chemokine SDF-1 level in rats increased significantly during the early postoperative phase (reaching a peak at the second estrus phase) in rat endometrium (P<0.05), its special receptor CXCR-4 expression did not differ significantly compared with the control group in rats or patients (P>0.05). Our findings indicated that aberrant activation of fibrosis and expression of ERα may be involved in the pathology of IUA formation. The role of the SDF-1/CXCR-4 axis in IUAs as inflammatory medium in the short-term or special homing factors for bone marrow mesenchymal stem cells requires further verification in in vivo animal models.

Ultrasonography in Experimental Reproductive Investigations on Rats

With the development of assisted reproductive technology and the ethical limitations of research on humans, rat animal models have been widely used in reproductive medicine. In the past, the study of reproductive system development in rodents has been based on one-time histological examination of excised tissues. Recently, with the development of high-resolution transabdominal ultrasound, high-quality sonography can now be performed to evaluate the reproductive organs of rats, allowing a new method for studying the reproductive system. Images were obtained using a high-resolution ultrasonographic system. Gynecological ultrasonography was performed on 28 eight-week-old non-pregnant rats and 5 pregnant Sprague-Dawley rats. We describe how to recognize organs of the reproductive system and associated structures in typical views during different phases of the estrus cycle. Color flow Doppler was used to measure uterine artery blood flow and evaluate uterine blood flow pattern changes during different stages of pregnancy. We have demonstrated that ultrasound exploration is a useful method for evaluating changes in internal reproductive organs. Its use raises the possibility of conducting additional experiments, including medical or surgical procedures, and provides the ability to monitor sonographic changes to internal organs without sacrificing animals.