The synergistic effect of electroacupuncture and bone mesenchymal stem cell transplantation on repairing thin endometrial injury in rats

Interceed combined with bone marrow mesenchymal stem cells improves endometrial receptivity of intrauterine adhesion

Background

This study aimed to investigate the impact of intrauterine adhesions (IUA) therapy and endometrial receptivity by implanting autologous bone marrow mesenchymal stem cells (BMSCs) into the Interceed and subsequently placing them in the uterine cavity of rats.

Methods

Fifty rats were divided into 5 groups according to the random number table method (10 rats in each group). Following the development of the IUA model through mechanical injury, the animals were categorized into different treatment groups: the IUA model (intrauterine perfusion of saline), Interceed therapy (intrauterine placement of Interceed), BMSCs therapy (intrauterine perfusion of BMSCs), BMSCs + Interceed therapy (intrauterine placement of BMSCs + Interceed), and a control group (intrauterine perfusion of saline). The Hematoxylin-eosin (HE) staining technique was employed to identify and assess the pathological alterations in the endometrium. Additionally, it facilitated the quantification of endometrial glands and the determination of endometrial thickness. Masson staining was used to detect fibrosis in rat uterus. The number of microvascular density (MVD) was detected by immunohistochemistry (IHC). Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot were used to detect the levels of leukemia inhibitory factor (LIF), integrin ανβ3, and vascular endothelial growth factor (VEGF) in uterine tissue. Male and female rats were combined in cages for reproductive and conception evaluation.

Results

In comparison to the control, the number of endometrial glands in the IUA model was significantly reduced, and the degree of endometrial thinning and fibrosis was significantly increased (p < 0.05). Compared with the IUA model, the number of endometrial glands did not exhibit any significant alterations in endometrial thickness and MVD number. The expressions of LIF, integrin ανβ3, and VEGF in the uterine tissue were not significantly improved with Interceed therapy, resulting in no significant improvement in the pregnancy rate (p > 0.05). The number of endometrial glands, endometrial thickness, and MVD in the BMSCs therapy group were significantly increased. Moreover, the expressions of LIF, integrin ανβ3, and VEGF in uterine tissue exhibited a significant increase, leading to a comparatively higher pregnancy rate (p < 0.05). In the BMSCs + Interceed therapy group, the number of endometrial glands, endometrial thickness, and MVD were significantly increased, and the expressions of LIF, integrin ανβ3, and VEGF in uterine tissue were significantly increased as well, along with a corresponding rise in the pregnancy rate (p < 0.05).

Conclusion

The intrauterine placement of Interceed combined with BMSCs in IUA rats can thicken the damaged endometrium, increase the number of glands, promote endometrial angiogenesis, improve endometrial receptivity, and increase the rate of pregnancy in IUA rats.

An Acellular, Self-Healed Trilayer Cryogel for Osteochondral Regeneration in Rabbits

Osteochondral regeneration remains formidable challenges despite significant advances in microsurgery. Herein, an acellular trilayer cryogel (TC) with injectability, tunable pore sizes (80-200 µm), and appropriate compressive modulus (10.8 kPa) is manufactured from self-healable hydrogel under different gelling times through Schiff reaction between chitosan and difunctionalized polyurethane (DFPU). Bioactive molecules (Y27632 and dexamethasone) are respectively loaded in the top and bottom layers to form the Y27632/dexamethasone-loaded trilayer cryogel (Y/DEX-TC). Mesenchymal stem cells (MSCs) seeded in Y/DEX-TC proliferated ≈350% in vitro and underwent chondrogenesis or osteogenesis in response to the respective release of Y or DEX in 14 days. Acupuncture is administered to animals in an attempt to modulate the innate regulatory system and mobilize endogenous MSCs for osteochondral defect regeneration. In vivo rabbit experiments using Y/DEX-TC combined with acupuncture successfully regulate SDF-1 and TGF-β1 levels, which possibly cause MSC migration toward Y/DEX-TC. The synergistic effect of cryogel and acupuncture on immunomodulation is verified with a ≈7.3-fold enhancement of the M2-/M1-macrophage population ratio by treatment of Y/DEX-TC combining acupuncture, significantly greater than ≈1.5-fold increase by acupuncture or ≈2.2-fold increase by Y/DEX-TC alone. This novel strategy using acellular drug-loaded cryogel and accessible acupuncture shows promise in treating osteochondral defects of joint damage.

A Novel Method to Repair Thin Endometrium and Restore Fertility Based on Menstruation-Derived Stem Cell

Thin endometrium (TE), which mainly occurs as a result of severe damage to the endometrial basalis, is one of the prominent etiologies of menstrual abnormalities, infertility, and recurrent miscarriage in women. Previous studies have demonstrated that mesenchymal stem cells (MSCs) are considered ideal cells with multipotency for regenerative medicine and exhibit therapeutic effects on TE through their cellular secretions. However, there is limited research on strategies to enhance MSC secretion to improve their therapeutic efficacy. Herein, we isolated menstrual blood-derived mesenchymal stem cells (MenSCs) from menstruation and transformed them into decidualized stromal cells (DSCs), which are specialized cells with enhanced secretory functions. To assess the therapeutic potential of DSCs compared to MenSCs, we conducted a series of experiments in cells and animals. The results demonstrated that DSCs exhibited changes in morphology compared to MenSCs, with a decrease in cell proliferation but a significant improvement in secretion function. Furthermore, DSCs facilitated the restoration of endometrial thickness and increased the number of glands and blood vessel formation. Most importantly, the pregnancy rates in rats were effectively restored, bringing them closer to normal levels. These findings greatly contribute to our understanding of stem cell therapy for TE and strongly suggest that DSCs could hold significant promise as a potential treatment option for TE.

Treatment of cytokine release syndrome-induced vascular endothelial injury using mesenchymal stem cells

Cytokine release syndrome (CRS) is an acute systemic inflammatory reaction in which hyperactivated immune cells suddenly release a large amount of cytokines, leading to exaggerated inflammatory responses, multiple organ dysfunction, and even death. Although palliative treatment strategies have significantly reduced the overall mortality, novel targeted treatment regimens with superior therapy efficacy are urgently needed. Vascular endothelial cells (ECs) are important target cells of systemic inflammation, and their destruction is considered to be the initiating event underlying many serious complications of CRS. Mesenchymal stem/stromal cells (MSCs) are multipotent cells with self-renewing differentiation capacity and immunomodulatory properties. MSC transplantation can effectively suppress the activation of immune cells, reduce the bulk release of cytokines, and repair damaged tissues and organs. Here, we review the molecular mechanisms underlying CRS-induced vascular endothelial injury and discuss potential treatments using MSCs. Preclinical studies demonstrate that MSC therapy can effectively repair endothelium damage and thus reduce the incidence and severity of ensuing CRS-induced complications. This review highlights the therapeutic role of MSCs in fighting against CRS-induced EC damage, and summarizes the possible therapeutic formulations of MSCs for improved efficacy in future clinical trials.

Combination of bone marrow mesenchymal stem cells and moxibustion restores cyclophosphamide-induced premature ovarian insufficiency by improving mitochondrial function and regulating mitophagy

BACKGROUND

Premature ovarian insufficiency (POI) is a major cause of infertility. In this study, we aimed to investigate the effects of the combination of bone marrow mesenchymal stem cells (BMSCs) and moxibustion (BMSCs-MOX) on POI and evaluate the underlying mechanisms.

METHODS

A POI rat model was established by injecting different doses of cyclophosphamide (Cy). The modeling of POI and the effects of the treatments were assessed by evaluating estrous cycle, serum hormone levels, ovarian weight, ovarian index, and ovarian histopathological analysis. The effects of moxibustion on BMSCs migration were evaluated by tracking DiR-labeled BMSCs and analyzing the expression of chemokines stromal cell-derived factor 1 (Sdf1) and chemokine receptor type 4 (Cxcr4). Mitochondrial function and mitophagy were assessed by measuring the levels of reactive oxygen species (ROS), mitochondrial membrane potential (MMP), ATP, and the mitophagy markers (Drp1, Pink1, and Parkin). Furthermore, the mitophagy inhibitor Mdivi-1 and the mitophagy activator CCCP were used to confirm the role of mitophagy in Cy-induced ovarian injury and the underlying mechanism of combination therapy.

RESULTS

A suitable rat model of POI was established using Cy injection. Compared to moxibustion or BMSCs transplantation alone, BMSCs-MOX showed improved outcomes, such as reduced estrous cycle disorders, improved ovarian weight and index, normalized serum hormone levels, increased ovarian reserve, and reduced follicle atresia. Moxibustion enhanced Sdf1 and Cxcr4 expression, promoting BMSCs migration. BMSCs-MOX reduced ROS levels; upregulated MMP and ATP levels in ovarian granulosa cells (GCs); and downregulated Drp1, Pink1, and Parkin expression in ovarian tissues. Mdivi-1 significantly mitigated mitochondrial dysfunction in ovarian GCs and improved ovarian function. CCCP inhibited the ability of BMSCs-MOX treatment to regulate mitophagy and ameliorate Cy-induced ovarian injury.

CONCLUSIONS

Moxibustion enhanced the migration and homing of BMSCs following transplantation and improves their ability to repair ovarian damage. The combination of BMSCs and moxibustion effectively reduced the excessive activation of mitophagy, which helped prevent mitochondrial damage, ultimately improving ovarian function. These findings provide a novel approach for the treatment of pathological ovarian aging and offer new insights into enhancing the efficacy of stem cell therapy for POI patients.

Establishment and comparison of different procedures for modeling intrauterine adhesion in rats: A preliminary study

The establishment of a stable animal model for intrauterine adhesion (IUA) can significantly enhance research on the pathogenesis and pathological changes of this disease, as well as on the development of innovative therapeutic approaches. In this study, three different modeling methods, including phenol mucilage combined mechanical scraping, ethanol combined mechanical scraping and ethanol modeling alone were designed. The morphological characteristics of the models were evaluated. The underlying mechanisms and fertility capacity of the ethanol modeling group were analyzed and compared to those of the sham surgery group. All three methods resulted in severe intrauterine adhesions, with ethanol being identified as a reliable modeling agent and was subsequently subjected to further evaluation. Immunohistochemistry and RT-PCR results indicated that the ethanol modeling group exhibited an increase in the degree of fibrosis and inflammation, as well as a significant reduction in endometrial thickness, gland number, vascularization, and endometrial receptivity, ultimately resulting in the loss of fertility capacity. The aforementioned findings indicate that the intrauterine perfusion of 95 % ethanol is efficacious in inducing the development of intrauterine adhesions in rats. Given its cost-effectiveness, efficacy, and stability in IUA formation, the use of 95 % ethanol intrauterine perfusion may serve as a novel platform for evaluating innovative anti-adhesion materials and bioengineered therapies.

Impaired receptivity of thin endometrium: therapeutic potential of mesenchymal stem cells

The endometrium is a resilient and highly dynamic tissue, undergoing cyclic renewal in preparation for embryo implantation. Cyclic endometrial regeneration depends on the intact function of several cell types, including parenchymal, endothelial, and immune cells, as well as adult stem cells that can arise from endometrial or extrauterine sources. The ability of the endometrium to undergo rapid, repeated regeneration without scarring is unique to this tissue. However, if this tissue renewal process is disrupted or dysfunctional, women may present clinically with infertility due to endometrial scarring or persistent atrophic/thin endometrium. Such disorders are rate-limiting in the treatment of female infertility and in the success of in vitro fertilization because of a dearth of treatment options specifically targeting the endometrium. A growing number of studies have explored the potential of adult stem cells, including mesenchymal stem cells (MSCs), to treat women with disorders of endometrial regeneration. MSCs are multipotent adult stem cells with capacity to differentiate into cells such as adipocytes, chondrocytes, and osteoblasts. In addition to their differentiation capacity, MSCs migrate toward injured sites where they secrete bioactive factors (e.g. cytokines, chemokines, growth factors, proteins and extracellular vesicles) to aid in tissue repair. These factors modulate biological processes critical for tissue regeneration, such as angiogenesis, cell migration and immunomodulation. The MSC secretome has therefore attracted significant attention for its therapeutic potential. In the uterus, studies utilizing rodent models and limited human trials have shown a potential benefit of MSCs and the MSC secretome in treatment of endometrial infertility. This review will explore the potential of MSCs to treat women with impaired endometrial receptivity due to a thin endometrium or endometrial scarring. We will provide context supporting leveraging MSCs for this purpose by including a review of mechanisms by which the MSC secretome promotes regeneration and repair of nonreproductive tissues.

Injectable collagen hydrogel combines human umbilical cord mesenchymal stem cells to promote endometrial regeneration in rats with thin endometrium

The regeneration of thin endometrium still remains as a great challenge in the field of reproductive medicine. Stem cells-based therapy has been considered as a promising strategy for the restoration of thin endometrium. However, the low transplantation and retention rate of stem cells and loss of stemness due to in vitro expansion limits the therapeutic efficacy. In our study, we combined collagen hydrogel and human umbilical cord mesenchymal stem cells (uMSCs) for improving the regeneration of thin endometrium, by using the potent pluripotency and low immunogenicity of uMSCs and collagen hydrogel that promotes the anchorage and proliferation of stem cells. Results showed that collagen hydrogel has favorable biocompatibility and the capacity to enhance the cell viability and expression of stemness-associated genes (including organic cation/carnitine transporter4 (Oct-4), Nanog homeobox (Nanog) and SRY-box transcription factor 2 (SOX2)) of uMSCs. The combination of collagen hydrogel and uMSCs prolonged the retention time of the constructs in the uterine cavity and improved endometrial thickness compared with uMSCs alone, leading to increase the fertility of the rats with thin endometrium. These highlighted therapeutic prospects of collagen hydrogel combined with uMSCs for the minimally invasive therapy of thin endometrium in the clinic.

Sodium alginate hydrogel integrated with type III collagen and mesenchymal stem cell to promote endometrium regeneration and fertility restoration

A thinner endometrium has been linked to implantation failure, and various therapeutic strategies have been attempted to improve endometrial regeneration, including the use of mesenchymal stem cells (MSCs). However, low survival and retention rates of transplanted stem cells are main obstacles to efficient stem cell therapy in thin endometrium. Collagen type III is a key component of the extracellular matrix, plays a crucial role in promoting cell proliferation and differentiation, and has been identified as the major collagen expressed at the implantation site. Herein, composite alginate hydrogel containing recombinant type III collagen (rCo III) and umbilical cord mesenchymal stem cells are developed. rCo III serves as favorable bioactive molecule, displaying that rCo III administration promotes MSCs proliferation, stemness maintenance and migration. Moreover, rCo III administration enhances cell viability and migration of mouse endometrial stromal cells (ESCs). In a mouse model of thin endometrium, the Alg-rCo III hydrogel loaded with MSCs (MSC/Alg-rCo III) significantly induces endometrial regeneration and fertility enhancement in vivo. Further studies demonstrate that the MSC/Alg-rCo III hydrogel promoted endometrial function recovery partly by regulating mesenchymal-epithelial transition of ESCs. Taken together, the combination of Alg-rCo III hydrogel and MSCs has shown promising results in promoting endometrium regeneration and fertility restoration, and may provide new therapeutic options for endometrial disease.

Imaging biomarker for quantitative analysis of endometrial injury based on optical coherence tomography/ultrasound integrated imaging mode

Precise evaluation of endometrial injury is significant to clinical decision-making in gynecological disease and assisted reproductive technology. However, there is a lack of assessment methods for endometrium in vivo. In this research, we intend to develop quantitative imaging markers with optical coherence tomography (OCT)/ultrasound (US) integrated imaging system through intrauterine endoscopic imaging. OCT/US integrated imaging system was established as our previous research reported. The endometrial injury model was established and after treatment, OCT/US integrated imaging and uterus biopsy was performed to evaluate the endometrial thickness, number of superficial fold, and intrauterine area. According to the results, three quantitative indexes acquired from OCT/US image and HE staining have the same trend and have a strong relationship with the severity of the endometrial injury. Accordingly, we developed three imaging markers for quantitative analysis of endometrial injury in vivo, which provided a precise mode for endometrium evaluation in clinical practice.

Electroacupuncture alleviates intrauterine adhesion through regulating autophagy in rats

Autophagy is a well-conserved metabolic system that maintains homeostasis by relying on lysosomal breakdown. The endometrium of patients with intrauterine adhesion (IUA) and an animal model exhibits impaired autophagy. Autophagy is negatively correlated with inflammation. Activation of autophagy can inhibit the inflammatory response, while defects in autophagy will activate the inflammatory response. Here, we studied whether electroacupuncture (EA) inhibits inflammation and promotes endometrial injury repair by activating endometrial autophagy. The IUA animal model was established by mechanical injury plus lipopolysaccharide infection. EA stimulation was applied to the acupoints Guanyuan (CV4), bilateral Sanyinjiao (SP6), and Zusanli (ST36). The results indicated that EA could improve endometrial morphology, attenuate endometrial fibers, and enhance endometrial receptivity in the rat. EA could increase the autophagosomes of endometrial epithelial cells, increase the levels of LC3 and Beclin1, and decrease the level of p62. Additionally, EA may also suppress the nuclear factor kappa-B (NF-κB) signaling pathway and reduce the release of inflammatory factors. Additionally, the effect of EA was comparable to that of the autophagy agonist rapamycin, and the autophagy inhibitor 3-methyladenine reversed the therapeutic effect of EA. Therefore, we assume that EA may facilitate endometrial healing by activating autophagy and reducing NF-κB signal pathway-mediated inflammation.

Effect and mechanism of acupuncture on endogenous and exogenous stem cells in disease treatment: A therapeutic review

Acupuncture is effective intervention, particularly in nerve, endocrine diseases and immune diseases. The potential mechanisms mediating the effects of acupuncture include anti-inflammatory and oxidative stress, inhibition of cell apoptosis, and stimulation of the proliferation and differentiation of endogenous stem cells. Traditional Chinese medicine combined with stem cell transplantation have a synergistic effect in the treatment of diseases. Increasing studies have found that acupuncture can promote the proliferation, differentiation, homing and survival of exogenous stem cells. This article reviews the mechanism of acupuncture and Chinese herbs on endogenous stem cells and exogenous stem cells in the combined intervention of diverse disorders and the major problems in past 15 years, which will provide a reference for future clinical research.

Oxycodone alleviates mifepristone-stimulated human endometrial stromal cell injury by activating the Keap1/Nrf2/HO-1 signaling pathway

BACKGROUND

Endometrial injury is a common disease in women caused by intrauterine inflammation, infections, and endocrine disorders. Human endometrial stromal cells (hEndoSCs) can maintain endometrial homeostasis and play an important role in repairing endometrial injury. Mifepristone, a steroidal anti-progesterone drug, is widely used in the field of reproductive medicine worldwide. Mifepristone-induced hEndoSC injury has been used to study endometrial injury in vitro. At present, the pathogenesis and potential regulatory mechanisms of oxycodone in endometrial injury remain unknown.

AIMS

We aimed to evaluate the functions of oxycodone in mifepristone-stimulated hEndoSC injury and analyze its potential molecular mechanism.

MATERIALS & METHODS

hEndoSC viability, cytotoxicity, and apoptosis were analyzed using the methyl thiazolyl tetrazolium assay, the lactate dehydrogenase assay, and flow cytometry, respectively. Furthermore, the levels of cleaved-Caspase3, Keap1, Nrf2, HO-1, and NQO1 were assessed using reverse transcription quantitative polymerase chain reaction and western blot analysis, and the release of inflammatory cytokines was determined using the enzyme-linked immunosorbent assay.

RESULTS

We observed that oxycodone had no adverse effects on hEndoSCs; rather, it protected hEndoSCs against mifepristone-induced endometrial damage, as confirmed by the enhanced cell viability, reduced number of apoptotic cells, decreased Caspase3 activity and inflammatory cytokine secretion, and increased Keap1/Nrf2/HO-1 pathway-related protein expression. In addition, we found that the protective effects of oxycodone on mifepristone-induced hEndoSC injury were inhibited by ML385 (a Keap1/Nrf2/HO-1 inhibitor).

CONCLUSION

In summary, we confirmed that oxycodone alleviates mifepristone-induced hEndoSC injury by activating the Keap1/Nrf2/HO-1 signaling pathway.

Network Pharmacology Analysis of the Mechanisms Underlying the Therapeutic Effects of Yangjing Zhongyu Tang on Thin Endometrium

Purpose

Yangjing Zhongyu Tang (YJZYT) is a classic Chinese prescription for infertility treatment and exerts therapeutic effects via activity on the thin endometrium (TE). However, the major components and underlying mechanisms of YJZYT actions remain to be established. The main objectives of this study were to clarify the effects of YJZYT on the TE and provide insights into the related mechanisms based on network pharmacology and molecular docking analyses.

Methods

Network pharmacology was employed to explore the main bioactive components and targets of YJZYT. TE-related genes were obtained from the Genecards database and screened for intersections with YJZYT. The Cytoscape 3.8.2 was used to build a "compounds-disease-targets" network and molecular docking analysis performed on key targets. The mechanism of action of YJZYT was further validated in vivo using a rat model.

Results

A total of 98 YJZYT active ingredients, 2409 thin endometrium-associated genes, and 186 common targets were obtained. Through topological analysis, 10 core objectives were screened. Data from the PPI network suggest that AKT1, TNF, VEGFA, IL-6, TP53, INS, ESR1, MMP9, ALB, and ACTB serve as key targets in the action of YJZYT on TE. PI3K-Akt, TNF, apoptosis, IL-17 and MAPK were established as the main functional pathways. Molecular docking analysis revealed high affinity of the active ingredients of YJZYT, specifically, ursolic acid, palbinone, stigmasterol, and beta-sitosterol, for TNF, VEGFA, IL-6, AKT, and MMP9. YJZYT improved endometrial recovery, promoted endometrial angiogenesis, and upregulated protein expression of VEGF, PI3K, AKT, and p-AKT in the TE rat model.

Conclusion

Network pharmacological and animal studies facilitated the prediction and validation of the active components and key targets of YJZYT potentially contributing to TE. Preliminary evidence from in vivo experiments showed that YJZYT promotes angiogenesis and thin endometrial repair via regulation of the PI3K/AKT pathway, providing a reference for further research.

Functionalized Human Umbilical Cord Mesenchymal Stem Cells and Injectable HA/Gel Hydrogel Synergy in Endometrial Repair and Fertility Recovery

Intrauterine adhesions (IUA) caused by endometrial injury are one of the main causes of female infertility. The current treatments for endometrial injury offer limited clinical benefits and cannot improve endometrial receptivity and pregnancy outcomes. Tissue engineering and regenerative medicine are considered potential solutions to address this concern and may offer effective treatment methods for the regeneration of injured human endometrium. Herein, we prepared an injectable hydrogel based on oxidized hyaluronic acid (HA-CHO) and hydrazide-grafted gelatin (Gel-ADH). The injectable hydrogel showed satisfactory biocompatibility when mixed with human umbilical cord mesenchymal stem cells (hUCMSCs). In an endometrial injury rat model, the treatment with hUCMSCs-loaded injectable hydrogel significantly enhanced the thickness of the endometrium and increased the abundance of blood vessels and glands in the injured endometrium compared to the control group. The hUCMSCs-loaded injectable hydrogel treatment significantly reduced endometrial fibrosis, decreased the expression of the pro-inflammatory factors (IL-1β and IL-6) and increased the expression of the anti-inflammatory factor (IL-10). This treatment induced endometrial VEGF expression by activating the MEK/ERK1/2 signaling pathway. Moreover, this treatment improved endometrial receptivity to the embryo and restored the embryo implantation rate similar to the sham group (48% in the sham group vs 46% in the treatment group), and this treatment achieved pregnancy and live birth in rats with endometrial injury. In addition, we also preliminarily validated the safety of this treatment in the maternal rats and fetuses. Collectively, our study showed that the hUCMSCs-loaded injectable hydrogel hold potential as an effective treatment strategy promoting rapid recovery of endometrial injury, and this hydrogel is a promising biomaterial for regenerative medicine applications. STATEMENT OF SIGNIFICANCE: : 1. Oxidized hyaluronic acid (HA-CHO)/hydrazide-grafted gelatin (Gel-ADH) hydrogel combined with human umbilical cord mesenchymal stem cells (hUCMSCs) are effective in improving the regeneration of endometrium in the endometrial injury rat model. 2. The hUCMSCs-loaded hydrogel treatment promotes the expression of endometrial VEGF through MEK/ERK1/2 signaling pathway and regulates the balance of inflammatory factors. 3. The embryo implantation and live birth rates restore to normal level in the endometrial injury rat model, and the hydrogel has no adverse effects on maternal rats, fetuses, and offspring development after the treatments.

EFFECT OF EXOSOMES DERIVED FROM BONE MARROW MESENCHYMAL STEM CELLS ON PROGRAMMED CELL DEATH IN BLAST-INDUCED LUNG INJURY IN RATS

ABSTRACT

Blast lung injuries (BLIs) are frequent because of industrial accidents and terrorist groups. Bone marrow mesenchymal stem cells (BMSCs) and exosomes derived from BMSCs (BMSCs-Exo) have become a hot topic in modern biology because of their significance in damage healing, immune regulation, and gene therapy. The aim of this study is to investigate the effect of BMSCs and BMSCs-Exo on BLI in rats caused by gas explosion. Here, BMSCs and BMSCs-Exo were transplanted into BLI rats via tail vein and then evaluated pathological alterations, oxidative stress, apoptosis, autophagy, and pyroptosis in the lung tissue. Through histopathology and changes in malondialdehyde (MDA) and superoxide dismutase (SOD) contents, we discovered that oxidative stress and inflammatory infiltration in the lungs were significantly reduced by BMSCs and BMSCs-Exo. After treatment with BMSCs and BMSCs-Exo, apoptosis-related proteins, such as cleaved caspase-3 and Bax, were significantly decreased, and the ratio of Bcl-2/Bax was significantly increased; the level of pyroptosis-associated proteins, including NLRP3, GSDMD-N, cleaved caspase-1, IL-1β, and IL-18, were decreased; autophagy-related proteins, beclin-1 and LC3, were downregulated while P62 was upregulated; the number of autophagosomes was decreased. In summary, BMSCs and BMSCs-Exo attenuate BLI caused by gas explosion, which may be associated with apoptosis, aberrant autophagy, and pyroptosis.

The protective effects of electroacupuncture on intestinal barrier lesions in IBS and UC model

Irritable bowel syndrome (IBS) and ulcerative colitis (UC) are two intestinal diseases with different pathological changes. Electroacupuncture (EA) at Zusanli (ST36) on both IBS and UC is widely used in clinic practice. But it is unclear whether acupuncture at one acupoint can treat two different intestinal diseases at different layers of intestinal barrier. To address this question, we explored three intestinal barrier lesions in IBS and UC mice with the aid of transcriptome data analysis and studied the efficacy of EA at ST36 on them. The transcriptome data analysis showed that both UC and IBS had disrupted intestinal barrier in various layers. And both UC and IBS had epithelial barrier lesions with reduction of ZO-1, Occludin and Claudin-1, while UC rather than IBS had the destruction of the mucus barrier with less MUC2 expression. As to the vascular barrier, UC showed a higher CD31 level and mesenteric blood flow reduction, while IBS showed a lower PV-1 level. EA at ST36 can significantly improve the above lesions of intestinal barrier of IBS and UC. Our results gave more details about the comprehensive protective effect of EA for UC and IBS. We guess the effect of acupuncture may be a kind of homeostasis regulation.

Herpetin Promotes Bone Marrow Mesenchymal Stem Cells to Alleviate Carbon Tetrachloride-Induced Acute Liver Injury in Mice

Herpetin, an active compound derived from the seeds of Herpetospermum caudigerum Wall., is a traditional Tibetan herbal medicine that is used for the treatment of hepatobiliary diseases. The aim of this study was to evaluate the stimulant effect of herpetin on bone marrow mesenchymal stem cells (BMSCs) to improve acute liver injury (ALI). In vitro results showed that herpetin treatment enhanced expression of the liver-specific proteins alpha-fetoprotein, albumin, and cytokeratin 18; increased cytochrome P450 family 3 subfamily a member 4 activity; and increased the glycogen-storage capacity of BMSCs. Mice with ALI induced by carbon tetrachloride (CCl₄) were treated with a combination of BMSCs by tail-vein injection and herpetin by intraperitoneal injection. Hematoxylin and eosin staining and serum biochemical index detection showed that the liver function of ALI mice improved after administration of herpetin combined with BMSCs. Western blotting results suggested that the stromal cell-derived factor-1/C-X-C motif chemokine receptor 4 axis and the Wnt/β-catenin pathway in the liver tissue were activated after treatment with herpetin and BMSCs. Therefore, herpetin is a promising BMSC induction agent, and coadministration of herpetin and BMSCs may affect the treatment of ALI.

Exosome-Based Regimen Rescues Endometrial Fibrosis in Intrauterine Adhesions Via Targeting Clinical Fibrosis Biomarkers

Intrauterine adhesions (IUA), which is characterized by endometrial fibrosis, continue to be the most common cause of uterine infertility globally. Our work revealed that 3 fibrotic progression markers (Vimentin, COL5A2, and COL1A1) were significantly increased in the endometrium of IUA patients. Mesenchymal stem cell-derived exosomes (EXOs) have been recently revealed as a cell-free therapy for fibrosis diseases. Nevertheless, the application of EXOs is restricted by the short residency duration in the target tissue. To overcome this limitation, herein, we reported an exosome-based regimen (EXOs-HP) that thermosensitive poloxamer hydrogel possessed the ability to efficiently promote the residency duration of EXOs in the uterine cavity. By downregulating fibrotic progression markers (Vimentin, COL5A2, and COL1A1), EXOs-HP could significantly restore the function and structure of the injured endometrium in the IUA model. Our work provides the theoretical and experimental foundation of EXOs-HP in treating IUA, highlighting the clinical potential of topical EXOs-HP delivery system in IUA patients.

Injectable self-assembled dual-crosslinked alginate/recombinant collagen-based hydrogel for endometrium regeneration

The disadvantages of mainstream therapies for endometrial injury are difficult to resolve, herein, we suggest an omnibearing improvement strategy by introducing an injectable multifunctional self-assembled dual-crosslinked sodium alginate/recombinant collagen hydrogel. The hydrogel possessed a reversible and dynamic double network based on dynamic covalent bonds and ionic interactions, which also contributed to excellent capability in viscosity and injectability. Moreover, it was also biodegradable with a suitable speed, giving off active ingredients during the degradation process and eventually disappearing completely. In vitro tests exhibited that the hydrogel was biocompatible and able to enhance endometrial stromal cells viability. These features synergistically promoted cell multiplication and maintenance of endometrial hormone homeostasis, which accelerated endometrial matrix regeneration and structural reconstruction after severe injury in vivo. Furthermore, we explored the interrelation between the hydrogel characteristics, endometrial structure, and postoperative uterine recovery, which would benefit deep research on regulation of uterine repair mechanism and optimization of hydrogel materials. The injectable hydrogel could achieve favourable therapeutic efficacy without the need of exogenous hormones or cells, which would be of clinical value in endometrium regeneration.

Therapeutic effect of menstrual blood stem cells in rats with thin endometrium

OBJECTIVES

To explore the therapeutic effect of transplantation of menstrual blood stem cells (MenSCs) in rats with thin endometrium.

METHODS

Thirty SPF grade female SD rats aged 8-10 weeks were randomly divided into model control group and MenSC group, with 15 rats in each group. The thin endometrium injury model was prepared by chemical method in one side of the uterus of both groups. On the 7th day of modeling, normal saline or the third generation of MenSCs were injected into the model uterus at multiple points, and the other side of the uterus was used as an internal control without treatment. HE staining was used to observe the histological structure of endometrium; immunohistochemical staining was used to observe the expression of cyto-keratin (CK) 18 and vimentin in endometrial tissue; 5-ethynyl-2'-deoxyuridine (EdU) cell proliferation assay was used to evaluate the cell proliferation in endometrial tissue; immunofluorescence staining was used to detect the expression of vascular endothelial marker CD34 and vascular endothelial growth factor (VEGF) in endometrial tissue; the expression of leukemia inhibitory factor (LIF), integrin β3 (ITGβ3) and homeobox A10 (HOXA10) in endometrial tissue was determined by realtime RT-PCR. After treatments, the female and male rats were caged in a ratio of 2∶1 to observe the effect of MenSC on the reproductive function of thin endometrium model rats.

RESULTS

Compared with the surgical control group, the endometrium in the model control group was thinner, and the numbers of glands and blood vessels were less (all P<0.01). After MenSC transplantation, the thickness of endometrium, the numbers of blood vessels and glands were significantly increased (all P<0.01). The proliferative cells in the basal layer of endometrium in MenSC group were more than those in the model control group (P<0.05), and the expression of vimentin, CK18, CD34 and VEGF in the uterus of rats in MenSC group were significantly higher than those in the model control group (P<0.05). LIF, ITGβ3 and HOXA10 gene expression levels were also significantly higher than those in the model control group (all P<0.05). The results of pregnancy experiment showed that the number of embryo implantation in MenSC group was higher than that in model control group (P<0.05).

CONCLUSIONS

MenSC transplantation can promote the proliferation of endometrial cells, upregulate vimentin, CK18, CD34 and VEGF levels, and promote the recovery of endometrial morphology and function, thus improving the endometrial receptivity and fertility of the rats with thin endometrium.

Effect of acupuncture for disorders of consciousness in patients with stroke: A systematic review and meta-analysis

Background

Disorder of consciousness (DOC) is frequent in patients with stroke, which is the second most common cause of death and a leading cause of disability. Acupuncture has been used as a curative method for DOC treatment in China. Nevertheless, no critical systematic review of acupuncture's effect on DOC has been published. This review aims to evaluate the present evidence regarding the efficacy of acupuncture for DOC after stroke.

Methods

Seven databases were searched from their inception to November 1, 2021, containing three English databases (PubMed, Embase, and Cochrane Central Register of Controlled Trials) and four Chinese databases (CNKI, CBM, VIP, and Wanfang Database). The primary outcomes comprise the Glasgow Coma Scale (GCS) and Glasgow Outcome Scale (GOS) before and after treatment. Secondary outcomes involve resuscitation rate, resuscitation time, and adverse events. Data synthesis was calculated by RevMan (V.5.4.1) software. According to the Cochrane Handbook, methodological quality was assessed with the risk of bias tool 2.0 (RoB2).

Results

Seventeen studies containing 1,208 patients were eventually included in our review. Overall, most trials were rated as high or had some concerns regarding the risk of bias. GCS was reported in 16 trials, and a meta-analysis showed that GCS improvement in the acupuncture group was greater than in the non-acupuncture group (MD 1.45, 95% CI 0.94-1.97, P < 0.0001). One trial reported that GOS improvement in the acupuncture plus medication group was greater than in the medication group (MD 0.58, 95% CI 0.11-1.05, P = 0.01). Another study reported that acupuncture plus medication was statistically more effective in shortening resuscitation time than medication alone (MD-0.89, 95% CI -1.53 to -0.25, P = 0.006). Four trials reported that the resuscitation rate in the acupuncture group was higher than without acupuncture intervention (RR 1.68, 95% CI 1.30-2.18, I 2 0%, P = 0.39). Adverse events were reported in two studies, with one case in the acupuncture group suffering from subcutaneous hematoma.

Conclusion

Acupuncture may improve consciousness level, increase the resuscitation rate, and shorten resuscitation time for post-stroke patients with DOC. Adverse events from acupuncture were rare, tolerable, and recoverable. However, the results should be interpreted cautiously, and more rigorous RCTs with better methodology are warranted.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=289802, identifier 289802.

Transplantation of bFGF-transfected bone mesenchymal stem cells on collagen scaffolds promotes the regeneration of injured rat endometrium

OBJECTIVE

This study aimed to verify the role of basic fibroblast growth factor (bFGF)-bone mesenchymal stem cells (BMSCs) loaded on collagen scaffolds for the repair of injured endometrium.

METHODS

We established an intrauterine adhesion (IUA) model in rats by endometrial resection and implanted BMSCs and bFGF-BMSCs loaded on collagen scaffolds into uteri. A total of 100 IUA model rats were divided into five groups: the control group, scaffold group, BMSC+scaffold group, vector-BMSC group, and bFGF-BMSC+scaffold group. The rats were sacrificed on the 3^rd, 7^th, 15^th, and 45^th days. The endometrium thickness, number of glands, and microvascular density were measured by hematoxylin and eosin staining, Masson staining, and immunohistochemistry staining of CD31. The expression of bFGF, vascular endothelial growth factor (VEGF), vimentin, and Ki67 was assayed by immunohistochemistry staining.

RESULTS

The bFGF-BMSCs loaded on the collagen scaffold significantly increased the endometrial thickness, gland number, and microvascular density, which greatly promoted the regeneration of the injured endometrium (P<0.0001). In addition, the expression levels of bFGF, VEGF, vimentin, and Ki67 were significantly higher in the bFGF-BMSC+scaffold group than in the BMSC+scaffold group (P<0.05).

CONCLUSIONS

Our findings indicated that bFGF-BMSCs loaded on collagen scaffolds have the ability to prompt the regeneration of the endometrium after injury, contributing to a better understanding of stem cell treatment for intrauterine adhesion.

Bone marrow mesenchymal stem cell-derived extracellular vesicles facilitate endometrial injury repair by carrying the E3 ubiquitin ligase WWP1

Bone marrow mesenchymal stem cells-derived extracellular vesicles (BMSC-EVs) relieve endometrial injury. This study aimed to elucidate the BMSC-EV mechanism in alleviating endometrial injury. Endometrial injury model in vivo was induced using 95% ethanol, and endometrial epithelial cells (EECs) treated with mifepristone were applied as an endometrial injury model in vitro. After BMSCs and BMSC-EVs were isolated and identified, the BMSC-EV function was evaluated by hematoxylin-eosin and Masson staining, immunohistochemistry, quantitative real-time PCR, Cell Counting Kit-8 assay, flow cytometry, enzyme-linked immunosorbent assay, and Transwell and tubule formation assays. The BMSC-EV mechanism was assessed using Western blot, ubiquitination, and cycloheximide-chase assays. After isolation and identification, BMSC-EVs were effective in endometrial injury repair in vivo and facilitated EEC proliferation and repressed cell apoptosis in vitro; the EEC supernatants accelerated human umbilical vein endothelial cell proliferation, migration, and invasion and facilitated angiogenesis after endometrial injury in vitro. For the BMSC-EV mechanism, E3 ubiquitin ligase WWP1 in BMSC-EVs mediated the ubiquitination of peroxisome proliferator-activated receptor gamma (PPARγ), thus relieving the PPARγ inhibition on vascular endothelial growth factor expression. Furthermore, the WWP1 in BMSC-EVs alleviated endometrial injury in vitro and in vivo. BMSC-EVs facilitated endometrial injury repair by carrying WWP1.

Bone marrow mesenchymal stem cells combined with estrogen synergistically promote endometrial regeneration and reverse EMT via Wnt/β-catenin signaling pathway

BACKGROUND

Intrauterine adhesion (IUA) is a clinical disease characterized by the uterine cavity occlusion caused by the damage of the endometrial basal layer. Bone marrow mesenchymal stem cells (BMSCs) transplantation have the potential to promote endometrial regeneration mainly through paracrine ability. Estrogen is an indispensable and important factor in the repair of endometrial damage, which has been reported as a promising and adjunctive therapeutic application for stem cell transplantation therapy. This study aims to investigate the synergistic effect of BMSCs and estrogen on improving the endometrial regeneration and restoring the endometrium morphology in a dual damage model of IUA in rabbits and the underlying molecular mechanisms.

METHODS

BMSCs were isolated and identified by adipogenic and osteogenic differentiation and flow cytometry assays. The rabbit IUA animal model was established by a dual damage method of mechanical curettage and lipopolysaccharide infection. Additionally, we investigated the therapeutic impact of both BMSCs and estrogen either separately or in combination in a rabbit model. The retention of PKH26-labeled BMSCs was observed by vivo fluorescence imaging.The number of endometrial glands and the degree of fibrosis were observed by H&E and Masson staining respectively. Western blotting, Immunohistochemistry and immunofluorescence staining were performed to detect biomarkers related to endometrial epithelium, endometrial fibrosis and EMT. Finally, the protein expression of core molecules of Wnt/β-catenin pathway was detected by Western blotting.

RESULTS

PKH26-labeled fluorescence results revealed that BMSCs appeared and located in the endometrial glands and extracellular matrix area when orthotopic transplanted into the uterine cavity. Histological assays showed that remarkably increasing the number of endometrial glands and decreasing the area of endometrial fibrosis in the BMSCs combined with estrogen treatment group. Moreover, downregulated expression of fibrosis markers (fibronectin, CollagenI, a-SMA) and interstitial markers (ZEB1, Vimentin, N-cadherin), as well as upregulated E-cadherin expression were found in the combined group. Further study of in vivo staining revealed that fluorescence intensity of CK7 was stronger in the combined group than that of direct BMSCs intrauterine transplantation, while vimentin showed the opposite results. Moreover, the protein levels of β-catenin, Axin2, C-myc, CycinE of Wnt/β-catenin signaling pathway increased in the BMSCs combined with estrogen group than in the other treatment groups.

CONCLUSION

BMSCs combined with estrogen can promote the differentiation of stem cells into endometrial epithelial cells to facilitate the regeneration of damaged endometrium. The potential mechanism of the synergistic effect may inhibit the occurrence of EMT by activating the Wnt/β-catenin signaling pathway.

Human umbilical cord blood-derived MSCs trans-differentiate into endometrial cells and regulate Th17/Treg balance through NF-κB signaling in rabbit intrauterine adhesions endometrium

Purpose

The fundamental cause of intrauterine adhesions (IUAs) is the destruction and reduction in stem cells in endometrial basal layer, resulting in endometrial reconstruction very difficult. The purpose of this study was to investigate the effects and underlying mechanism of human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) on the endometrial reconstruction after transplantation.

Methods

hUCB-MSCs were isolated and identified by flow cytometry, osteogenic, adipogenic and chondrogenic differentiation assays. The rabbit IUA models were established and set five groups (control, 14/28th day after surgery, estrogen and hUCB-MSCs treatment). The number of endometrial glands and the fibrosis rate were evaluated using HE and Masson staining, respectively. Endometrial proliferation, angiogenesis and inflammation were evaluated by immunohistochemical staining of ER, Ki-67and TGF-β1, respectively. Single-cell RNA sequencing (scRNA-seq) was applied to explore the cell differentiation trajectory after hUCB-MSCs transplanted into IUA endometrium. Finally, molecular mechanism of hUCB-MSCs repairing damaged endometrium was investigated by RNA sequencing, qRT-PCR and Western blot assays.

Results

After transplantation of the hUCB-MSCs, the increase in endometrial gland number, estrogen receptor (ER) and Ki-67 expression, and the decrease in fibrosis rate and TGF-β expression (P < 0.05), suggested the endometrial repair, angiogenesis and inflammatory suppression. The therapeutic effect of hUCB-MSCs was significantly improved compared with 28th day after surgery and estrogen group. ScRNA-seq demonstrated that the transplanted hUCB-MSCs can trans-differentiate into endometrial cells: epithelial, fibroblast and macrophage. RNA sequencing of six IUA samples combined with qRT-PCR and Western blot assays further revealed that hUCB-MSCs may regulate Th17/Treg balance through NF-κB signaling, thus inhibiting the immune response of damaged endometrium.

Conclusions

Our study demonstrated that hUCB-MSCs can repair damaged endometrium through trans-differentiation, immunomodulatory capacities and NF-κB signaling, suggesting the treatment value of hUCB-MSCs in IUA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02990-1.

Human Umbilical Cord Mesenchymal Stem Cells Encapsulated with Pluronic F-127 Enhance the Regeneration and Angiogenesis of Thin Endometrium in Rat via Local IL-1β Stimulation

Thin endometrium (< 7 mm) could cause low clinical pregnancy, reduced live birth, increased spontaneous abortion, and decreased birth weight. However, the treatments for thin endometrium have not been well developed. In this study, we aim to determine the role of Pluronic F-127 (PF-127) encapsulation of human umbilical cord mesenchymal stem cells (hUC-MSCs) in the regeneration of thin endometrium and its underlying mechanism. Thin endometrium rat model was created by infusion of 95% ethanol. Thin endometrium modeled rat uterus were treated with saline, hUC-MSCs, PF-127, or hUC-MSCs plus PF-127 separately. Regenerated rat uterus was measured for gene expression levels of angiogenesis factors and histological morphology. Angiogenesis capacity of interleukin-1 beta (IL-1β)-primed hUC-MSCs was monitored via quantitative polymerase chain reaction (q-PCR), Luminex assay, and tube formation assay. Decreased endometrium thickness and gland number and increased inflammatory factor IL-1β were achieved in the thin endometrium rat model. Embedding of hUC-MSCs with PF-127 could prolong the hUC-MSCs retaining, which could further enhance endometrium thickness and gland number in the thin endometrium rat model via increasing angiogenesis capacity. Conditional medium derived from IL-1β-primed hUC-MSCs increased the concentration of angiogenesis factors (basic fibroblast growth factor (bFGF), vascular endothelial growth factors (VEGF), and hepatocyte growth factor (HGF)). Improvement in the thickness, number of glands, and newly generated blood vessels could be achieved by uterus endometrium treatment with PF-127 and hUC-MSCs transplantation. Local IL-1β stimulation-primed hUC-MSCs promoted the release of angiogenesis factors and may play a vital role on thin endometrium regeneration.

Basic Fibroblast Growth Factor (bFGF)-Overexpressed Bone Marrow Mesenchymal Stem Cells (BMSCs) Orchestrate Lung Cancer Development and Fibroblast Growth

Lung cancer is one of most common cancer with a complicated pathogenesis and a poor prognosis. This study aimed to investigate the role of bFGF and BMSCs in lung cancer progression. BMSCs were transfected with bFGF mimic or NC and then co-cultured with lung cancer cells followed by measuring cell migration by Transwell assay and proliferation by CCK-8 assay, expression of bFGF, E-cadherin, and Vimentin by RT-qPCR and Western blot. The BMSCs were positive for CD90, CD71, CD29 and CD45. Overexpression of bFGF in BMSCs resulted in increased lung cancer cell proliferation at 24 h, 48 h and 72 h. Meanwhile, bFGF overexpression also significantly promoted cell migration and invasion as well as upregulated bFGF (4.03±0.36 ng/μl) and E-cadherin (3.64±0.27 ng/μl) and downregulated Vimentin (1.45±0.19 ng/μl). In conclusion, co-culture of BMSCs overexpressing bFGF and lung cancer cells enhances BMSCs differentiation and promotes cancer cell development possibly through regulation of E-cadherin and Vimentin expression, indicating that this might be a novel approach for the treatment of lung cancer.

Oxycodone Alleviates Endometrial Injury via the TLR4/NF-κB Pathway

Endometrial injury is a common female disease. This study was designed to illustrate the effects of oxycodone on mifepristone-induced human endometrial stromal cells (hEndoSCs) injury and delineate the underlying molecular mechanism. hEndoSCs were stimulated with mifepristone to generate the endometrial injury in vitro model. hEndoSCs viability, cytotoxicity, and apoptosis were measured by methyl thiazolyl tetrazolium (MTT) assay, lactate dehydrogenase assay (LDH), and flow cytometry (FCM) analysis, respectively. Meanwhile, quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blot assay were conducted to evaluate gene and protein expressions. The secretions of inflammatory cytokines (TNF-α, IL-1β, and IL-6) were measured using enzyme-linked immunosorbent assay (ELISA). The data revealed that mifepristone exposure memorably inhibited hEndoSCs viability and promoted cell apoptosis and inflammatory cytokines secretion, and oxycodone had no cytotoxicity on hEndoSCs. Oxycodone increased hEndoSCs growth, blocked cell apoptosis, enhanced Bcl-2 expression, reduced Bax levels, and decreased the secretion of inflammatory cytokines in mifepristone-induced hEndoSCs, exhibiting the protective effects in endometrial injury. In addition, the TLR4/NF-κB pathway-related protein levels (TLR4 and p-p65) in mifepristone-treated hEndoSCs were enhanced, while these enhancements were inhibited by oxycodone treatment. In conclusion, oxycodone exhibited the protective role in mifepristone-triggered endometrial injury via inhibiting the TLR4/NF-κB signal pathway.

Combination of stem cell therapy and acupuncture to treat ischemic stroke: a prospective review

Stroke is the second leading cause globally that leads to severe disability and death. Stem cell therapy has been developed over the recent years to treat stroke and diminish the mortality and disability rate of brain injuries. Acupuncture, which can activate endogenous recovery via physical stimuli, has been applied to enhance the recovery and rehabilitation of stroke patients. Attempts have been made to combine stem cell therapy and acupuncture to treat stroke patients and have shown the promising results. This prospective review will look into the possible mechanisms of stem cell therapy and acupuncture and intend to undercover the potential benefit of the combined therapy. It intends to bridge the modern emerging stem cell therapy and traditional acupuncture at cellular and molecular levels and to demonstrate the potential benefit to improve clinical outcomes.

The safety and efficacy of mesenchymal stem cell therapy in diabetic lower extremity vascular disease: a meta-analysis and systematic review

BACKGROUND AIMS

Several studies have shown the efficacy of mesenchymal stem cell (MSC) therapy for lower extremity vascular disease (LEVD) in diabetic patients, but the results are not consistent. Therefore, the authors conducted a meta-analysis of randomized controlled trials (RCTs) to examine the safety and efficacy of MSC therapy in diabetic patients with LEVD.

METHODS

Eight available databases were searched in both English and Chinese to identify RCTs comparing MSC therapy-based conventional treatment with conventional treatment alone in diabetic patients with LEVD. Three investigators independently screened the literature, extracted the data and assessed the risk bias. Meta-analysis was performed using RevMan 5.4.1 and Stata 14.0.

RESULTS

A total of 10 studies involving 453 patients were included. Compared with conventional treatment only, patients receiving MSC therapy-based conventional treatment had a higher ulcer healing rate, greater number of reduced ulcers and shorter complete healing time. MSC therapy also increased ankle-brachial index and transcutaneous oxygen pressure. In addition, four of the included studies showed that MSC therapy significantly improved the number of new collateral vessels. Moreover, no more adverse events were recorded in the MSC group.

CONCLUSIONS

This meta-analysis suggests that MSC therapy promotes ulcer healing in diabetic LEVD patients with ulcers, improves blood supply and has a favorable safety profile. More large and well-designed RCTs with long-term follow-up are still needed to explore the safety and efficacy of MSC therapy in diabetic patients with LEVD.

Synergistic regenerative therapy of thin endometrium by human placenta-derived mesenchymal stem cells encapsulated within hyaluronic acid hydrogels

Background

Thin endometrium is a primary cause of defective endometrial receptivity, resulting in infertility or recurrent miscarriage. Much effort has been devoted toward regenerating thin endometrium by stem cell-based therapies. The human placenta-derived mesenchymal stem cells (HP-MSCs) are emerging alternative sources of MSCs with various advantages. To maximize their retention inside the uterus, we loaded HP-MSCs with cross-linked hyaluronic acid hydrogel (HA hydrogel) to investigate their therapeutic efficacy and possible underlying mechanisms.

Methods

Ethanol was injected into the mice uterus to establish the endometrium-injured model. The retention time of HP-MSCs and HA hydrogel was detected by in vivo imaging, while the distribution of HP-MSCs was detected by immunofluorescence staining. Functional restoration of the uterus was assessed by testing embryo implantation rates. The endometrial morphological alteration was observed by H&E staining, Masson staining, and immunohistochemistry. In vitro studies were further conducted using EdU, transwell, tube formation, and western blot assays.

Results

Instilled HP-MSCs with HA hydrogel (HP-MSCs-HA) exhibited a prolonged retention time in mouse uteri than normal HP-MSCs. In vivo studies showed that the HP-MSCs-HA could significantly increase the gland number and endometrial thickness (P < 0.001, P < 0.05), decrease fibrous area (P < 0.0001), and promote the proliferation and angiogenesis of endometrial cells (as indicated by Ki67 and VEGF, P < 0.05, P < 0.05, respectively) in mice injured endometrium. HP-MSCs-HA could also significantly improve the embryo implantation rate (P < 0.01) compared with the ethanol group. Further mechanistic study showed the paracrine effects of HP-MSCs. They could not only promote the proliferation and migration of human endometrial stromal cells via the JNK/Erk1/2-Stat3-VEGF pathway but also facilitate the proliferation of glandular cells via Jak2-Stat5 and c-Fos-VEGF pathway. In turn, the increased VEGF in the endometrium promoted the angiogenesis of endothelial cells.

Conclusion

Our study suggested the potential therapeutic effects and the underlying mechanisms of HP-MSCs-HA on treating thin endometrium. HA hydrogel could be a preferable delivery method for HP-MSCs, and the strategy represents a promising therapeutic approach against endometrial injury in clinical settings.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02717-2.

Evidence-Based Application of Acupuncture in Theriogenology

Historical evidence of acupuncture predates written history. It has been a component of Traditional Chinese veterinary medicine for many generations and is officially recognized in recorded history for treating equine disease in the Zhou Dynasty, circa 1050 BC. Drawing from a range of searchable databases, we present the use of veterinary acupuncture related to theriogenology. We touch on human-based medicine only as an introduction to current uses within veterinary medical acupuncture. This review is confined to the use of acupuncture encompassing dry needle, electroacupuncture, aquapuncture, and the few reports of laserpuncture. Starting with acupuncture’s influence on the master organs of reproduction, the hypothalamus and the pituitary glands, and the hypothalamic–pituitary–gonadal axis, we then review reports specific to the gonads—ovaries and testicles—and then its influences on the uterus. From there, we review reports on the influence of acupuncture on pain associated with reproductive surgery, and finally, on the use of acupuncture for maternal lactation. Based on published reports, we conclude that acupuncture has been shown to be effective in many situations as a treatment for infertility and/or reproductive tract disfunction, resulting in improvements in both female and male patients.

Transplantation of umbilical cord-derived mesenchymal stem cells promotes the recovery of thin endometrium in rats

The endometrium plays a critical role in embryo implantation and pregnancy, and a thin uterus is recognized as a key factor in embryo implantation failure. Umbilical cord mesenchymal stem cells (UC-MSCs) have attracted interest for the repair of intrauterine adhesions. The current study investigated the repair of thin endometrium in rats using the UC-MSCs and the mechanisms involved. Rats were injected with 95% ethanol to establish a model of thin endometrium. The rats were randomly divided into normal, sham, model, and UC-MSCs groups. Endometrial morphological alterations were observed by hematoxylin-eosin staining and Masson staining, and functional restoration was assessed by testing embryo implantation. The interaction between UC-MSCs and rat endometrial stromal cells (ESCs) was evaluated using a transwell 3D model and immunocytochemistry. Microarray mRNA and miRNA platforms were used for miRNA-mRNA expression profiling. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analyses were performed to identify the biological processes, molecular functions, cellular components, and pathways of endometrial injury and UC-MSCs transplantation repair and real-time quantitative reverse transcription PCR (qRT-PCR) was performed to further identify the expression changes of key molecules in the pathways. Endometrium thickness, number of glands, and the embryo implantation numbers were improved, and the degree of fibrosis was significantly alleviated by UC-MSCs treatment in the rat model of thin endometrium. In vitro cell experiments showed that UC-MSCs migrated to injured ESCs and enhanced their proliferation. miRNA microarray chip results showed that expression of 45 miRNAs was downregulated in the injured endometrium and upregulated after UC-MSCs transplantation. Likewise, expression of 39 miRNAs was upregulated in the injured endometrium and downregulated after UC-MSCs transplantation. The miRNA-mRNA interactions showed the changes in the miRNA and mRNA network during the processes of endometrial injury and repair. GO and KEGG analyses showed that the process of endometrial injury was mainly attributed to the decomposition of the extracellular matrix (ECM), protein degradation and absorption, and accompanying inflammation. The process of UC-MSCs transplantation and repair were accompanied by the reconstruction of the ECM, regulation of chemokines and inflammation, and cell proliferation and apoptosis. The key molecules involved in ECM-receptor interaction pathways were further verified by qRT-PCR. Itga1 and Thbs expression decreased in the model group and increased by UC-MSCs transplantation, while Laminin and Collagen expression increased in both the model group and MSCs group, with greater expression observed in the latter. This study showed that UC-MSCs transplantation could promote recovery of thin endometrial morphology and function. Furthermore, it revealed the expression changes of miRNA and mRNA after endometrial injury and UC-MSCs transplantation repair processed, and signaling pathways that may be involved in endometrial injury and repair.

Human menstrual blood-derived mesenchymal stem cells regulation of the EGF/Ras p21 pathway as a potential therapeutic target for thin endometrium

Background

Human infertility is caused by many factors, among which thin endometrium is the main reason for poor embryo implantation. Currently, stem cell therapy could be a potential approach in treating human endometrial disorder like thin endometrium. In this study, we aimed to explore the influence of menstrual stem cells from non-thin endometrium (NTE-MenSCs) and thin endometrium (TE-MenSCs) on the phenotype of endometrial epithelial cells (EECs).

Methods

The MenSCs were isolated from women with and without thin endometria, characterized and co-cultured with the EECs. The expression of cytokeratin 7 (CK7) was verified by immunofluorescence while the detection stem cell markers was determined flow cytometry. Osteogenic and adipogenic differentiation were induced in appropriate media. The quantitative real-time PCR and western blotting were respectively used for detecting the mRNA and protein expression levels, respectively. The CCK-8 assay was used for cell viability analysis whereas ELISA was used for the detection of cytokine levels.

Results

The results showed that the co-culture of NTE-MenSCs or TE-MenSCs and EECs promoted the proliferation, migration, and angiogenesis of endothelial progenitor cells differently. Furthermore, the TE-MenSCs promoted the expression of inflammation, vascularized adipose, and extracellular matrix related proteins. The epidermal growth factor (EGF)/Ras p21 pathway was found to mediate the influence of MenSCs on EECs.

Conclusions

These findings are vital in that they may promote stem cell therapy of thin endometrium and enable embryo implantation in humans with thin endometrium.

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.

Effects of bone marrow mesenchymal stem cells on repair and receptivity of damaged endometrium in rats

AIM

This study was to investigate whether bone marrow mesenchymal stem cells (BMSCs) can repair damaged endometrium in rats and its effect on endometrial receptivity.

METHODS

A rat model of endometrial damage was established by heat injury. BMSCs were labeled with PKH26 and were transplanted into the right uterine cavity. The endometrial thickness and fertility testing were examined to assess the repair of damaged endometrium. The mass on trichrome staining was used to assess the endometrium fibrosis. The expression of integrin avβ3 and leukemia inhibitory factor (LIF) in rat endometrium was used to evaluate the endometrial receptivity.

RESULTS

After transplantation of BMSCs, the distribution of PKH26 positive cells was mainly on the damaged side in the endometrial tissues. Compared to control group, the endometrial tissue structure recovered after treatment with BMSCs. BMSCs transplantation improved the fertility of endometrial injury model rats. BMSCs decreased the area of endometrial fibrosis. The expression of integrin avβ3 and LIF in endometrium was the stronger in BMSCs treatment group than control group.

CONCLUSION

BMSCs can migrate to the endometrium and repair damaged endometrium and improve endometrium receptivity.

Adult stem cells in endometrial regeneration: Molecular insights and clinical applications

Endometrial damage is an important cause of female reproductive problems, manifested as menstrual abnormalities, infertility, recurrent pregnancy loss, and other complications. These conditions are collectively termed "Asherman syndrome" (AS) and are typically associated with recurrent induced pregnancy terminations, repeated diagnostic curettage and intrauterine infections. Cancer treatment also has unexpected detrimental side effects on endometrial function in survivors independently of ovarian effects. Endometrial stem cells act in the regeneration of the endometrium and in repair through direct differentiation or paracrine effects. Nonendometrial adult stem cells, such as bone marrow-derived mesenchymal stem cells and umbilical cord-derived mesenchymal stem cells, with autologous and allogenic applications, can also repair injured endometrial tissue in animal models of AS and in human studies. However, there remains a lack of research on the repair of the damaged endometrium after the reversal of tumors, especially endometrial cancers. Here, we review the biological mechanisms of endometrial regeneration, and research progress and challenges for adult stem cell therapy for damaged endometrium, and discuss the potential applications of their use for endometrial repair after cancer remission, especially in endometrial cancers. Successful application of such cells will improve reproductive parameters in patients with AS or cancer. Significance: The endometrium is the fertile ground for embryos, but damage to the endometrium will greatly impair female fertility. Adult stem cells combined with tissue engineering scaffold materials or not have made great progress in repairing the injured endometrium due to benign lesions. However, due to the lack of research on the repair of the damaged endometrium caused by malignant tumors or tumor therapies, the safety and effectiveness of such stem cell-based therapies need to be further explored. This review focuses on the molecular insights and clinical application potential of adult stem cells in endometrial regeneration and discusses the possible challenges or difficulties that need to be overcome in stem cell-based therapies for tumor survivors. The development of adult stem cell-related new programs will help repair damaged endometrium safely and effectively and meet fertility needs in tumor survivors.

Exploration of the potential mechanism of the Tao Hong Si Wu Decoction for the treatment of postpartum blood stasis based on network pharmacology and in vivo experimental verification

ETHNOPHARMACOLOGICAL RELEVANCE

Tao Hong Si Wu Decoction (THSWD) is a traditional prescription for blood management in traditional Chinese medicine, THSWD consists of Paeoniae Radix Alba (Paeonia lactiflora Pall.), Rehmanniae Radix Praeparata (Rehmannia glutinosa (Gaertn.) DC.), Angelicae Sinensis Radix (Angelica sinensis (Oliv.) Diels), Chuanxiong Rhizoma (Conioselinum anthriscoides 'Chuanxiong'), Persicae Seman (Prunus persica (L.) Batsch) and Carthami Flos (Carthamus tinctorius L.) at a weight ratio of 3: 4: 3: 2: 3: 2. THSWD is a commonly used prescription in the treatment of postpartum blood stasis disease.

AIM OF THE STUDY

To explore the potential mechanism of THSWD for the treatment of postpartum blood stasis using network pharmacology and experimental research.

MATERIALS AND METHODS

We extracted the active ingredients and targets in THSWD from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), and constructed a herbs-ingredients-targets-disease-network, devised a protein-protein interaction (PPI) network, performed GO enrichment analysis, and performed Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis to discover potential treatment mechanisms. A postpartum blood stasis model was established in rats, and the results of network pharmacology were verified by in vivo experiments.

RESULTS

The results showed that 69 potential active ingredients and 207 THSWD target genes for the treatment of postpartum blood stasis disease were obtained after ADME filtering analysis. The targets were enriched in multiple gene functions and different signaling pathways. By exploring various different signaling pathways, it was found that mitochondrial regulation of oxidative stress plays a potentially important role in the treatment of postpartum blood stasis with THSWD. Compared to model group, THSWD alleviated mitochondrial damage, decreased levels of oxidative stress in the rat model of postpartum blood stasis and reduced apoptosis in uterine cells.

CONCLUSION

The therapeutic effect of THSWD on postpartum blood stasis is likely related to mitochondrial regulation of oxidative stress, which paves the way for further research investigating its mechanisms.

Recent developments in bio-scaffold materials as delivery strategies for therapeutics for endometrium regeneration

Intrauterine adhesions (IUAs) refer to the repair disorder after endometrial injury and may lead to uterine infertility, recurrent miscarriage, abnormal menstrual bleeding, and other obstetric complications. It is a pressing public health issue among women of childbearing age. Presently, there are limited clinical treatments for IUA, and there is no sufficient evidence that these treatment modalities can effectively promote regeneration after severe endometrial injury or improve pregnancy outcome. The inhibitory pathological micro-environment is the main factor hindering the repair of endometrial damaged tissues. To address this, tissue engineering and regenerative medicine have been achieving promising developments. Particularly, biomaterials have been used to load stem cells or therapeutic factors or construct an in situ delivery system as a treatment strategy for endometrial injury repair. This article comprehensively discusses the characteristics of various bio-scaffold materials and their application as stem cell or therapeutic factor delivery systems constructed for uterine tissue regeneration.

Effectiveness of electroacupuncture for thin endometrium in infertile women: study protocol for a single-blind, randomized controlled trial

BACKGROUND

Thin endometrium negatively impacts the reproductive function. Current treatments for thin endometrium do not always improve endometrial receptivity. Preliminary evidence suggests that electroacupuncture could have potential therapy for thin endometrium in infertile women. Thus, this randomized controlled trial was designed to test whether electroacupuncture can improve endometrial receptivity in infertile women with thin endometrium.

METHODS

This study is a randomized, single-blinded, controlled, clinical trial. A total of 142 eligible patients will be recruited and randomly assigned to the electroacupuncture (EA) group or the sham electroacupuncture (SEA) group in a 1:1 ratio. Participants will receive 36 sessions over three menstrual cycles (12 weeks in total), with the same acupoint prescription. The primary outcome of this trial is endometrial thickness in the midluteal phase. The secondary outcomes include endometrial pattern, resistance index (RI) and pulsatility index (PI) of bilateral uterine artery and endometrium blood flow, serum estradiol (E2) and progesterone (P), and pregnancy rate. The pregnancy rate will be evaluated during a 6-month follow-up after completion of the trial. All other outcomes will be evaluated before treatment, during the treatment of 1st, 2nd, and 3rd menstrual cycle, and 6 months after treatment.

DISCUSSION

If the outcome confirms the effectiveness of electroacupuncture for thin endometrium in infertile women, this treatment will be proposed for application in clinical practice.

TRIAL REGISTRATION

Chinese Clinical Trials Registry ChiCTR2 000029983. Registered on 18 February 2020.

Cryogel/hydrogel biomaterials and acupuncture combined to promote diabetic skin wound healing through immunomodulation

Unhealed chronic wounds often deteriorate into multiple infection with several kinds of bacteria and excessive proteolytic wound exudate and remains one of the common healthcare issues. Here, the functional and antimicrobial hydrogel and cryogel biomaterials were prepared from glycol chitosan and a novel biodegradable Schiff base crosslinker difunctional polyurethane (DF-PU). The cryogel exhibited ~2730 ± 400% of water absorption with abundant macropores and 86.5 ± 1.6% of porosity formed by ice crystal as well as ~240% cell proliferation effect; while the hydrogel demonstrated considerable antimicrobial activity and biodegradability. As an optimized procedure to treat the diabetic skin wound in a rat model, the combined application of adipose stem cell-seeded cryogel/hydrogel biomaterials on the wound and acupuncture surrounding the wound may attain 90.34 ± 2.3% of wound closure and secure the formation of granulation tissue with sufficient microvessels and complete re-epithelialization in 8 days. The average increases in the superficial temperature of wounded animals after acupuncture were about 1-2 °C. Through the activation of C3a and C5a, the increased secretion of cytokines SDF-1 and TGFβ-1, as well as the down-regulation of proinflammatory cytokines TNF-α and IL-1β, the combined treatment of stem cell-seeded cryogel/hydrogel biomaterials and acupuncture on wounds produced synergistic immunomodulatory effects. The strategy using the combined treatment of biomaterials, stem cells, and acupuncture reveals a perspective new approach to accelerate the tissue regeneration.

A triple-coated ligament graft to facilitate ligament-bone healing by inhibiting fibrogenesis and promoting osteogenesis

Absence of ligament-bone healing due to poor bioactivity and hyperplasia of fibrous tissue caused by immune response severely impairs ligament grafts' functional duration in anterior cruciate ligament (ACL) reconstruction. While osteogenic modification is a popular technique for promoting ligament-bone integration, inadequate osseointegration remains a common experience, due to occupying fibrous hyperplasia and impaired osteogenesis potential. In the present study, a triple-nano-coating polyethylene terephthalate (PET) graft was developed by polydopamine self-assembly, chondroitin sulfate (CS) chemical-grafting and BMP-2 physical-immobilization to facilitate robust ligament-bone healing, The CS/polydopamine-modified PET (C-pPET) graft was demonstrated to inhibit fibrogenesis by regulating polarization of macrophages and promoting the secretion of anti-inflammatory factors. Moreover, the immunoregulatory function of CS cooperated with BMP-2 to facilitate osteogenic differentiation of stem cells, promoting the expression of ALP, Runx2, OCN and COL I. Bone regeneration was significantly enhanced at early-middle stage in the BMP-loaded pPET (B/pPET) group, while occurring at middle-late stage in the C-pPET group. Continuous new bone formation and optimal ligament-bone healing were observed in the B/C-pPET group via sequential and synergistic immune osteogenesis by CS and cytokine osteogenesis by BMP-2. Thus, the present study revealed a practical avenue for the promotion of ligament-bone healing through the development of a triple-nano-coating engineered ligament combining immunoregulatory anti-fibrogenesis and sequential-synergistic osteogenesis, which holds a great potential for improving the clinical efficacy of ligament graft in ACL reconstruction. STATEMENT OF SIGNIFICANCE: A triple-nano-coating polyethylene terephthalate (PET) graft was developed by polydopamine self-assembly, chondroitin sulfate (CS) chemical-grafting and BMP-2 physical-immobilization to facilitate robust ligament-bone healing. This study demonstrated that the multifunctional ligament grafts could reshape the local immune microenvironment by regulating macrophage phenotype and immune cytokine secretion to inhibit the fibrous hyperplasia and regulate stem cell towards osteogenic differentiation to promote bone regeneration. The present study demonstrates that efficient ligament-bone healing is achieved via the combination of immunoregulatory anti-fibrogenesis and dual osteogenesis of immunoregulation and cytokine induction.

Advances in the Application of Biomimetic Endometrium Interfaces for Uterine Bioengineering in Female Infertility

The Asherman’s syndrome, also known as intrauterine adhesion, often follows endometrium injuries resulting from dilation and curettage, hysteroscopic resection, and myomectomy as well as infection. It often leads to scarring formation and female infertility. Pathological changes mainly include gland atrophy, lack of vascular stromal tissues and hypoxia and anemia microenvironment in the adhesion areas. Surgical intervention, hormone therapy and intrauterine device implantation are the present clinical treatments for Asherman’s syndrome. However, they do not result in functional endometrium recovery or pregnancy rate improvement. Instead, an increasing number of researches have paid attention to the reconstruction of biomimetic endometrium interfaces with advanced tissue engineering technology in recent decades. From micro-scale cell sheet engineering and cell-seeded biological scaffolds to nano-scale extracellular vesicles and bioactive molecule delivery, biomimetic endometrium interfaces not only recreate physiological multi-layered structures but also restore an appropriate nutritional microenvironment by increasing vascularization and reducing immune responses. This review comprehensively discusses the advances in the application of novel biocompatible functionalized endometrium interface scaffolds for uterine tissue regeneration in female infertility.