Homogenous subpopulation of human mesenchymal stem cells and their extracellular vesicles restore function of endometrium in an experimental rat model of Asherman syndrome.

BACKGROUND: Asherman syndrome (AS), or intrauterine adhesions, is a main cause of infertility in reproductive age women after endometrial injury. Mesenchymal stem cells (MSCs) and their extracellular vesicles (EVs) are promising candidates for therapies that repair damaged endometria. However, concerns about their efficacy are attributed to heterogeneity of the cell populations and EVs. A homogenous population of MSCs and effective EV subpopulation are needed to develop potentially promising therapeutic options in regenerative medicine. METHODS: AS model was induced by mechanical injury in adult rat uteri. Then, the animals were treated immediately with homogeneous population of human bone marrow-derived clonal MSCs (cMSCs), heterogenous parental MSCs (hMSCs), or cMSCs-derived EV subpopulations (EV20K and EV110K). The animals were sacrificed two weeks post-treatment and uterine horns were collected. The sections were taken, and hematoxylin-eosin was used to examine the repair of endometrial structure. Fibrosis was measured by Masson's trichrome staining and α-SMA and cell proliferation by Ki67 immunostaining. The function of the uteri was explored by the result of mating trial test. Expression changes of TNFα, IL-10, VEGF, and LIF were assayed by ELISA. RESULTS: Histological analysis indicated fewer glands, thinner endometria, increased fibrotic areas, and decreased proliferation of epithelial and stroma of the uteri in the treated compared with intact and sham-operated animals. However, these parameters improved after transplantation of both types of cMSCs and hMSCs and/or both cryopreserved EVs subpopulations. The cMSCs demonstrated more successful implantation of the embryos in comparison with hMSCs. The tracing of the transplanted cMSCs and EVs showed that they migrated and localized in the uteri. Protein expression analysis results demonstrated downregulation of proinflammatory factor TNFα and upregulation of anti-inflammatory cytokine IL-10, and endometrial receptivity cytokines VEGF and LIF in cMSC- and EV20K-treated animals. CONCLUSION: Transplantation of MSCs and EVs contributed to endometrial repair and restoration of reproductive function, likely by inhibition of excessive fibrosis and inflammation, enhancement of endometrial cell proliferation, and regulation of molecular markers related to endometrial receptivity. Compared to classical hMSCs, cMSCs were more efficient than hMSCs in restoration of reproductive function. Moreover, EV20K is more cost-effective and feasible for prevention of AS in comparison with conventional EVs (EV110K).

Human Platelet-Rich Plasma Facilitates Angiogenesis to Restore Impaired Uterine Environments with Asherman's Syndrome for Embryo Implantation and Following Pregnancy in Mice.

Asherman's syndrome (AS) is caused by intrauterine adhesions and inactive endometrium from repeated curettage of the uterine endometrium. AS is a major cause of recurrent implantation failure and miscarriage and is very difficult to treat because of the poor recovery of endometrial basal cells. Platelet-rich plasma (PRP) has abundant growth factors that may induce angiogenesis and cell proliferation. Here, we demonstrate that human PRP (hPRP) significantly enhances angiogenesis to restore embryo implantation, leading to successful pregnancy in mice with AS. In mice with AS, hPRP treatment considerably reduced the expression of fibrosis markers and alleviated oligo/amenorrhea phenotypes. Mice with AS did not produce any pups, but the hPRP therapy restored their infertility. AS-induced abnormalities, such as aberrantly delayed embryo implantation and intrauterine growth retardation, were considerably eliminated by hPRP. Furthermore, hPRP significantly promoted not only the elevation of various angiogenic factors, but also the migration of endometrial stromal cells. It also increased the phosphorylation of STAT3, a critical mediator of wound healing, and the expression of tissue remodeling genes in a fibrotic uterus. PRP could be a promising therapeutic strategy to promote angiogenesis and reduce fibrosis in impaired uterine environments, leading to successful embryo implantation for better clinical outcomes in patients with AS.

Effects of adipose- derived stromal vascular fraction on asherman syndrome model.

Asherman's syndrome (AS) is an endometrial damage that results in infertility in women. Although stem cell therapy has been introduced as a potential treatment for this syndrome, its use in clinical settings remains challenging because of the likelihood of contamination and cell differentiation. Herein, we investigated the effects of adipose-derived stromal vascular fraction (SVF) transplantation on proliferation and angiogenesis in the endometrium in an AS model. The AS model was induced using scratch method in adult male Wistar rats, and SVF (5 × 10 (Simsir et al., 2019) cells) was locally administered into the damaged horns. Two weeks after cell transplantation, endometrial thickness, fibrosis, and expression of vascular endothelial growth factor (VEGF) were assessed by Hematoxylin & Eosin, Masson's trichrome, and immunofluorescence staining, respectively. We found thin endometrium, increased fibrosis, and decreased VEGF following AS induction all of which were reversed after SVF transplantation. We concluded that the local injection of SVF may serve as an effective alternative therapy for AS.

Perivascular Stem Cell-Derived Cyclophilin A Improves Uterine Environment with Asherman's Syndrome via HIF1α-Dependent Angiogenesis.

Asherman's syndrome (AS) is characterized by intrauterine adhesions or fibrosis resulting from scarring inside the endometrium. AS is associated with infertility, recurrent miscarriage, and placental abnormalities. Although mesenchymal stem cells show therapeutic promise for the treatment of AS, the molecular mechanisms underlying its pathophysiology remain unclear. We ascertained that mice with AS, like human patients with AS, suffer from extensive fibrosis, oligo/amenorrhea, and infertility. Human perivascular stem cells (hPVSCs) from umbilical cords repaired uterine damage in mice with AS, regardless of their delivery routes. In mice with AS, embryo implantation is aberrantly deferred, which leads to intrauterine growth restriction followed by no delivery at term. hPVSC administration significantly improved implantation defects and subsequent poor pregnancy outcomes via hypoxia inducible factor 1α (HIF1α)-dependent angiogenesis in a dose-dependent manner. Pharmacologic inhibition of HIF1α activity hindered hPVSC actions on pregnancy outcomes, whereas stabilization of HIF1α activity facilitated such actions. Furthermore, therapeutic effects of hPVSCs were not observed in uterine-specific HIF1α-knockout mice with AS. Secretome analyses of hPVSCs identified cyclophilin-A as the major paracrine factor for hPVSC therapy via HIF1α-dependent angiogenesis. Collectively, we demonstrate that hPVSCs-derived cyclophilin-A facilitates HIF1α-dependent angiogenesis to ameliorate compromised uterine environments in mice with AS, representing the major pathophysiologic features of humans with AS.

Adipose derived mesenchymal stem cell treatment in experimental asherman syndrome induced rats.

Asherman syndrome (AS) occurs due to fibrosis or uterine adhesions as a result of damage to the basal layer of the endometrium. The aim of this study is investigating the effects of adipose tissue-derived mesenchymal stem cell (ADMSC) application on the expression of vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF-1), miRNA-98, miRNA199a in endometrial tissue in rats with AS. Study groups were designed as, control (C), Asherman syndrome (AS), AS + oral estrogen (ASO), AS + ADMSC (ASSC), AS + oral estrogen + ADMSC (ASSCO) with 7 samples in each group. Characterization and differentiation experiments were performed in ADMSC obtained. Two weeks after the development of the AS, ADMSC therapy was applied. BrdU (5-bromo-2'-deoxyuridine) labeling was performed to show the presence of ADMSC in the tissues. Rats were sacrificed after 8 weeks and bilateral uterine horn resection was performed. Tissues were fixed in formaldehyde. After routine tissue follow-up, sections were taken and evaluated with hematoxylin eosin staining. VEGF1 and IGF1 expressions were evaluated by immunohistochemical staining and western blot analysis. Expression changes of miR-98 and miR-199a were detected by RT-PCR. Our results showed that stem cells and estrogen giving together reduced inflammation and fibrosis in the endometrium. Immunohistochemistry and western blot results suggested that this effect was achieved especially through IGF-1. In our study, decreased miR-98 and miR-199a expressions were determined in Asherman syndrome. Furthermore, no changes of miRNA expressions were observed in treatment groups.

Effects of uterus derived mesenchymal stem cells and their exosomes on asherman's syndrome.

Asherman's syndrome has become a growing problem with the incidence of cesarean and endometrial surgical procedures. A surgical procedure that can damage to the basal layer of the endometrium is formed as intrauterine adhesion and can cause asherman's syndrome. Mesenchymal stem cells (MSCs) are characterized by some characteristics such as non-immunogenic, angiogenic, antifibrotic, antiapoptotic and antiinflammatory properties, also they support tissue repair by secretion of various factors and chemokines in cellular therapy. Exosomes are active paracrine components with a great potential for repairing damaged tissue. Exosomes include many paracrine factors responsible for regeneration and angiogenesis. In this study, 10 newborn Wistar rats were used to obtain MSCs. A total of 24 adult Wistar rats were also used. The rats were divided into 4 groups: untreated control group; asherman control group; asherman + uterine-derived MSCs group; asherman + uterine-derived MSCs-exosomes group. At the end of the experiment, uterine tissues were evaluated by histochemical and immunohistochemical. As a result of MSCs and exosomes treatments, proliferation and vascularization in uterine tissue was increased. It was also shown to reduce fibrosis with masson's trichrome staining. MMP-2 and MMP-9 expression was enhanced by MSC and exosomal therapy; in addition, TIMP-2 expression was decreased. In our study, it was shown that proliferation and vascularization increased and fibrosis decreased in uterus as a result of MSC and exosome treatments. Our results indicate that the exosomal treatment restored the damage of asherman's syndrome at tissue at a shorter time than the MSCs group.

Antifibrotic Effects of Decellularized and Lyophilized Human Amniotic Membrane Transplant on the Formation of Intrauterine Adhesion.

OBJECTIVES: Intrauterine adhesion is a disease involving endometrial fibrosis that arises from injury to the basal layer of the endometrium. Here, we aimed to explore the preventive effects of decellularized and lyophilized amniotic membrane on endometrial fibrosis in a rat model of intrauterine adhesion. MATERIALS AND METHODS: Twenty-four Sprague-Dawley rats were randomly divided into 2 groups. For the intrauterine adhesion group, endometria of left uteri were scraped without treatment. For the intrauterine adhesion plus decellularized and lyophilized amniotic membrane transplant group, decellularized and lyophilized amniotic membrane was sutured onto the scraped wound of left uteri. Right uteri were kept as the control group. At 3, 7, 14, and 28 days after transplant, uteri were sampled for histologic and immunohistochemical evaluation. RESULTS: Histology examination revealed extensive fibrosis with significantly reduced numbers of endometrial glands in uteri in the intrauterine adhesion group. Immunohistochemical staining showed a remarked increase in expression of transforming growth factor ß1 (P < .01) and decreased expression of matrix metalloproteinase-9 (P < .01) in the intrauterine adhesion group. In rats with transplant of decellularized and lyophilized amniotic membrane, endometrial fibrosis apparently improved (P < .05) with reduced expression of transforming growth factor ß1 and increased matrix metalloproteinase-9 expression (P < .05). However, there were no significant differences in the number of endometrial glands or endometrial thickness between the 2 groups (P > .05). CONCLUSIONS: Development of intrauterine adhesion was prevented with transplant of decellularized and lyophilized amniotic membrane via suppression of transforming growth factor ß1 and increased production of matrix metalloproteinase-9 in a rat model.

Metformin Promotes Regeneration of the Injured Endometrium Via Inhibition of Endoplasmic Reticulum Stress-Induced Apoptosis.

Intrauterine adhesion (IUA) is now recognized as one of the most common diseases in reproductive-age women. Metformin, a well-known frontline oral antidiabetic drug, has been found effective in numerous different diseases. The aim of this study was to determine the effect of metformin on reducing adhesions in an animal model of IUA. Sprague-Dawley rats were randomized into 4 groups: sham operation, control, metformin-treated for 7 days, and metformin-treated for 14 days. To establish the IUA model, mechanical injury to the endometria of rats was induced with a mini curette. Metformin was injected intraperitoneally after surgery. A significant amelioration in both the number of glands and the fibrotic area, compared to those of the control group, was detected 14 days after metformin intervention. The expression levels of antigen KI-67 and vascular endothelial growth factor were increased at 7 and 14 days after treatment. However, the transforming growth factor-ß expression was decreased at 14 days after treatment. Endoplasmic reticulum stress-related apoptosis proteins (glucose-regulated protein 78, caspase-12, and CCAAT/enhancer binding protein (EBP) homologous protein) were downregulated after metformin treatment. Moreover, we determined that the effect of metformin was related to the inhibition of endoplasmic reticulum stress-induced apoptosis via the Phosphatidylinositol 3 kinase (PI3K)/Protein kinase B (AKT) and Extracellular regulated protein kinases1/2 pathways. In conclusion, metformin can attenuate the adhesion and promote the regeneration of the endometrium of the IUA rat, and metformin may serve as a novel therapeutic strategy for IUA patients.

Human mesenchymal stem cells in spheroids improve fertility in model animals with damaged endometrium.

BACKGROUND: Asherman's syndrome (AS) is one of the gynecological disorders caused by the destruction of the endometrium. For some cases of AS available surgical methods and hormonal therapy are ineffective. Stem cell transplantation may offer a potential alternative for AS cure. METHODS: Human endometrial mesenchymal stem cells (eMSC) organized in spheroids were transplanted in rats with damaged endometrium modeled on AS. Treatment response was defined as pregnancy outcome and litter size. RESULTS: Application of eMSC in spheroids significantly improved the rat fertility with the AS model. eMSC organized in spheroids retain all properties of eMSC in monolayer: growth characteristics, expression of CD markers, and differentiation potential. Synthesis of angiogenic and anti-inflammatory factors drastically increased in eMSC assembled into spheroids. CONCLUSIONS: Human endometrial mesenchymal stem cells (eMSC) can be successfully applied for Asherman's syndrome (AS) treatment in the rat model. eMSC organized in spheroids were more therapeutically effective than the cells in monolayer. After transplantation of eMSC in spheroids the pregnancy outcome and litter size in rats with AS was higher than in rats that received autologous rat bone marrow cells. It suggests the therapeutic plausibility of heterologous eMSC in case of failure to use autologous cells.

Elevated NF-κB signaling in Asherman syndrome patients and animal models.

Asherman syndrome (intrauterine adhesion) is often associated with menstrual abnormalities, infertility and recurrent miscarriage in female. Currently the molecular mechanism regulating the pathogenesis of Asherman syndrome is not known. Here we revealed that the inflammatory factor NF-κB expression is significantly elevated in the endometrial samples of Asherman syndrome patients. To further study the molecular mechanisms, we established an Asherman syndrome rat model and confirmed the important role of NF-κB in the pathogenesis of Asherman syndrome. In addition, our rat model provided direct evidence that intrauterine adhesion results in impaired pregnancy, supporting the clinical association between intrauterine adhesion and mis-regulated pregnancy. Our result identified NF-κB as a novel pathogenesis factor of Asherman syndrome and provided new insights for the prevention and treatment of intrauterine adhesions in Asherman syndrome patients.

Characteristics of Multipotent Mesenchymal Stromal Cells Isolated from the Endometrium and Endometriosis Lesions of Women with Malformations of the Internal Reproductive Organs.

We isolated and characterized cell cultures from eutopic endometrium and endometriotic lesions of women with malformations of the internal reproductive organs. The cells had fibroblast-like shape and intensively expressed CD90, CD73, CD105, CD44, CD146, and CD117 and were capable of induced adipogenic and osteogenic differentiation in vitro. The obtained cultures exhibited properties of multipotent mesenchymal stromal cells; at the same time, they demonstrated in vitro immunophenotypic differences from cell cultures of eutopic and ectopic endometrium of women without developmental abnormalities, which suggests their functional difference. The cells from eutopic endometrium and from ectopic endometriotic lesions can be used as the model for studying of the etiology and pathogenesis of endometriosis and for testing new drugs for this specific group of patients. Markers CD90 and CD117 were identified as promising molecules for the development of minimally invasive diagnostics of endometriosis based on cell cultures from eutopic endometrium.

Transplantation of collagen scaffold with autologous bone marrow mononuclear cells promotes functional endometrium reconstruction via downregulating ΔNp63 expression in Asherman's syndrome.

Asherman's syndrome (AS) is a common disease that presents endometrial regeneration disorder. However, little is known about its molecular features of this aregenerative endometrium in AS and how to reconstruct the functioning endometrium for the patients with AS. Here, we report that ΔNp63 is significantly upregulated in residual epithelial cells of the impaired endometrium in AS; the upregulated-ΔNp63 induces endometrial quiescence and alteration of stemness. Importantly, we demonstrate that engrafting high density of autologous bone marrow mononuclear cells (BMNCs) loaded in collagen scaffold onto the uterine lining of patients with AS downregulates ΔNp63 expression, reverses ΔNp63-induced pathological changes, normalizes the stemness alterations and restores endometrial regeneration. Finally, five patients achieved successful pregnancies and live births. Therefore, we conclude that ΔNp63 is a crucial therapeutic target for AS. This novel treatment significantly improves the outcome for the patients with severe AS.

Fertile ground: human endometrial programming and lessons in health and disease.

The human endometrium is a highly dynamic tissue that is cyclically shed, repaired, regenerated and remodelled, primarily under the orchestration of oestrogen and progesterone, in preparation for embryo implantation. Humans are among the very few species that menstruate and that, consequently, are equipped with unique cellular and molecular mechanisms controlling these cyclic processes. Many reproductive pathologies are specific to menstruating species, and studies in animal models rarely translate to humans. Abnormal remodelling and regeneration of the human endometrium leads to a range of reproductive complications. Furthermore, the processes regulating endometrial remodelling and implantation, including those controlling hormonal impact, breakdown and repair, stem/progenitor cell activation, inflammation and cell invasion have broad applications to other fields. This Review presents current knowledge regarding the normal and abnormal function of the human endometrium. The development of biomarkers for prediction of uterine diseases and pregnancy disorders and future avenues of investigation to improve fertility and enhance endometrial function are also discussed.

Human CD133(+) bone marrow-derived stem cells promote endometrial proliferation in a murine model of Asherman syndrome.

OBJECTIVE: To investigate the engraftment and proliferation of superparamagnetic iron oxide nanoparticles (SPIOs)-labeled human CD133(+) bone marrow-derived stem cells (BMDSCs) in an animal model of Asherman syndrome (AS). DESIGN: Prospective experimental animal study. SETTING: University research laboratories. ANIMAL(S): Nonobese diabetic mice (strain code 394; NOD.CB17- Prkdc(scid)/NcrCrl) in which AS was induced according to a published protocol. INTERVENTION(S): Human CD133(+) BMDSCs were obtained from patients undergoing autologous cell therapy in refractory AS and endometrial atrophy, labeled with SPIOs and injected either intrauterinely (n = 5) or systemically through the tail vein (n = 5) in the animal model. MAIN OUTCOME MEASURE(S): Accumulation of collagen and glycosaminoglycan deposits detected by trichrome staining. Percentage and localization of engrafted human SPIOs-labeled CD133(+) BMDSCs by Prussian blue staining. Cell proliferation assay using Ki67 and reverse transcriptase-polymerase chain reaction (PCR) for specific paracrine factors. RESULT(S): The induction of the AS in the murine model was demonstrated by the accumulation of collagen and glycosaminoglycan deposits in the damaged horns by trichrome staining. Human SPIOs labeled CD133(+) BMDSCs homing represents 0.59% and 0.65% of total number of cells present in the horns after intrauterine or tail vein injections, respectively. Engrafted cells were localized around endometrial blood vessels, inducing proliferation in surrounding cells based on Ki67 and regulation of the paracrine factors thrombospondin 1 and insulin-like growth factor 1. CONCLUSION(S): The injection of human SPIOs labeled CD133(+) BMDSCs in a murine model of AS confirms that these cells engraft around endometrial vessels, inducing proliferation of surrounding cells through paracrine molecules such as thrombospondin 1 and insulin-like growth factor 1. CLINICAL TRIAL REGISTRATION NUMBER: NCT02144987.

Effect of stem cell application on Asherman syndrome, an experimental rat model.

PURPOSE: We evaluate the effect of stem cells to induce endometrial proliferation and angiogenesis on Asherman Syndrome (AS). METHODS: The experimental study was performed in stemcell research laboratory. Forty Wistar-Albino rats were divided according to groups. In group1 (n = 10) to establish the model; trichloroacetic acid was injected to right uterine horn. Two weeks later, intrauterine synechia was confirmed. In group2 (n = 10), 2 weeks later, 2 × 106 mesenchymal stem cells (MSC) were injected into right uterine horn followed by three intraperitoneal injections of MSCs. In group3 (n = 10), daily oral estrogen was initiated on the second week. In group4 (n = 10), MSC injections and oral estrogen was given together. The amount of fibrosis, vascularisation, inflammation and immunohistochemical staining with vascular endothelial growth factor (VEGF), proliferating cell nuclear antigen (PCNA) and Ki-67 were evaluated in the uterine tissues. RESULTS: In all treatment groups; fibrosis decreased but vascularisation and immunhistohemical stainings increased in the experimental side. The amount of fibrosis, vascularisation, Ki-67 and PCNA scores were similar between group2 and 3. In group4, comparing to group2, less fibrosis but more Ki-67, PCNA and VEGF staining was observed. CONCLUSION: Stem cells, when added to estrogen, are a highly effective alternative to induce regeneration of endometrium in Asherman Syndrome therapy.