Effects of platelet-rich plasma on the activity of human menstrual blood-derived stromal cells in vitro

Human platelet-rich plasma promotes primordial follicle activation via the PI3K/Akt signaling pathway

The activation of dormant primordial follicles is a promising method to improve the fertility of premature ovarian insufficiency (POI) patients. Many experiments from both human and animal studies suggest that human platelet-rich plasma (hPRP) may restore ovarian function and promote follicle growth. However, the underlying mechanisms remain unclear. In the current study, our results demonstrate that hPRP significantly increased the number of growing follicles and promoted the proliferation of granulosa cells in cultured mouse ovaries. hPRP also significantly increased the protein levels of phosphorylated protein kinase B (p-Akt) and forkhead box O3a (p-FOXO3a), as well as the number of oocytes with FOXO3a nuclear export in cultured mouse ovaries. Immunofluorescence results showed that in vitro treatment with hPRP significantly increased the fluorescence intensity of p-Akt in oocytes. The inhibition of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway by LY294002 blocked the hPRP-induced increase in the number of growing follicles in cultured mouse ovaries. Furthermore, hPRP injected i.p. or added to the medium significantly increased the number of growing follicles and the protein levels of p-Akt in the ovaries of newborn mice and in cultured human ovarian tissues. Taken together, our findings from mouse and human experiments indicate that hPRP promotes the activation of primordial follicles through the PI3K/Akt signaling pathway in oocytes.

Cell origin and microenvironment: The players of differentiation capacity in human mesenchymal stem cells

Mesenchymal stem cells (MSCs) have several important properties that make them desirable for regenerative medicine. These properties include immunomodulatory ability, growth factor production, and differentiation into various cell types. Despite extensive research and promising results in clinical trials, our understanding of MSC biology, their mechanism of action, and their targeted and routine use in clinics is limited. Differentiation of human MSCs (hMSCs) is a complex process influenced by various elements such as growth factors, pharmaceutical compounds, microRNAs, 3D scaffolds, and mechanical and electrical stimulation. Research has shown that different culture conditions can affect the differentiation potential of hMSCs obtained from multiple fetal and adult sources. Additionally, it seems that what affects the differentiation capacities of these cells is their secretory characteristics, which are influenced by the origin of the cells and the local microenvironment where the cells are located. The review can provide insights into the microenvironment-based mechanisms involved in MSC differentiation, which can be valuable for future therapeutic applications.

The application of tissue engineering strategies for uterine regeneration

Uterine injuries, particularly damages to endometrium, are usually associated with abnormal menstruation, recurrent miscarriage, pregnancy complications, and infertility. Tissue engineering using cell-based, biomolecule-based, or biomaterial and scaffold-based strategies has emerged as a novel and promising approach for uterine regeneration. Stem cells, biomolecules, and porous scaffolds used alone or, very often, used in combination as a more effective treatment means have shown great potential in promoting uterine regeneration. The reported preclinical studies have indicated that appropriate tissue engineering strategies could safely and effectively reconstruct not only endometrium but also partial or even the whole uterine structure. However, the progress in the uterine regeneration area is slow in comparison to that of regenerating many other body tissues and hence it still remains a great challenge to apply uterine tissue engineering for clinical applications. In this review, conventional treatments for uterine-related diseases are briefly reviewed and discussed first. Subsequently, tissue engineering strategies (cell-based, biomolecule-based, biomaterial and scaffold-based, or their combinations) for uterine repair in preclinical studies and clinical trials are presented and analyzed. Finally, the challenges and perspectives in uterine regeneration are pointed and discussed. Despite various limitations and obstacles, the tissue engineering approach is viable and holds high promise for uterine regeneration.

The Effect of Autologous Platelet Rich Plasma on Endometrial Receptivity: A Narrative Review

Background and Objectives: Autologous platelet-rich plasma (PRP) transfusions are a relatively new treatment method used in different fields of medicine, including the field of reproductive medicine. One of the applications of these concentrated platelet infusions is the treatment of endometrial receptivity, which is a key factor for embryo implantation. There are implications that PRP infusions can lead to increased endometrial thickness, endometrial receptivity, and significantly elevated clinical pregnancy rates. Our objective is to briefly understand what PRP is and to, through a narrative review, summarize the findings from studies focused on evaluating the benefits of PRP infusions to treat thin endometrium with the goal of achieving better endometrial receptivity. Materials and Methods: Reference data was searched using Medline, PubMed, and EMBASE to identify reports from 2015 to 2024. The combination of search words used was "PRP" and "platelet-rich plasma" with "thin endometrium", "endometrial receptivity", "endometrial thickness", and "endometrial implantation". Obtained articles were screened, and suited studies (randomized controlled trials, case reports, case series, pilot studies, and reviews) were included in the present review. Reports not available in the English language were eliminated from the current review. Results: The results from most of the reviewed studies showed a positive effect of autologous PRP infusions on increasing endometrial thickness, enhancing endometrial receptivity, and elevating clinical pregnancy rates. The majority of the evaluated findings revealed endometrial thickness > 7 mm (increased endometrial thickness was observed in each evaluated study) following the PRP treatment. More than 50% of the evaluated studies resulted in enhanced endometrial thickness, increased endometrial receptivity, and an elevated pregnancy rate after the PRP application. Conclusions: Autologous PRP infusions for treating endometrium are a relatively new method that has shown promising results. Its major strengths are availability and proper application, which eliminates possible immunological reactions or disease transmission. The main drawbacks are not enough data on safety (i.e., its effect on endometriosis) and the lack of uniformity in the PRP preparation, which would provide optimal standardized quality and quantity of the PRP product and, thus, optimal treatment results.

Platelet-rich plasma effects on in vitro cells derived from pediatric patients with andrological diseases

Undescended testis and testicular torsion represent two frequent andrological diseases that affect the pediatric age. Despite these testicular disorders having different causes, they both negatively influence fertility in adulthood mainly due to the accumulation of reactive oxygen species (ROS), which represents the primary molecular damage underlying their long-term effects. The gold standard of treatment for both pathologies is surgery; however, it cannot guarantee an optimal fertility outcome in all clinical cases, underscoring the need to identify effective adjuvant therapies that may target the augmented ROS levels. For this aim, we investigated the pro-proliferative and anti-oxidant effects of PRP (platelet-rich plasma), a hemoderivative product used in regenerative medicine. We confirmed the increased oxidative status in testicular tissue by directly analyzing patients' biopsies with mass spectrometry and highlighting that three antioxidant proteins are significantly overexpressed compared to healthy testicles. Afterward, we in vitro treated cells derived from patients with cryptorchidism or testicular torsion with PRP, showing that it consistently decreases ROS levels and slightly induces cell proliferation. This study supports the potential use of PRP in patients with testis torsion or cryptorchidism, encouraging its future clinical application as adjuvant therapy to preserve the functionality of this organ by decreasing its ROS levels.

Effect of Different Concentrations of PRP on the Expression of Factors Involved in the Endometrial Receptivity in the Human Endometrial Cells from RIF Patients Compared to the Controls

Platelet-rich plasma (PRP) has been suggested for the improvement of endometrial growth and receptivity in the patients with recurrent implantation failure (RIF). The aim of present study was to investigate the impact of different concentration of PRP on the expression of genes involved in the endometrial receptivity in the human endometrial cells from RIF and controls with thin and normal endometrium in vitro. In this cross-sectional study, endometrial biopsies were obtained from 14 healthy fertile women and 14 women with RIF. Endometrial cells from 4 different group (RIF and control with endometrial thickness < 7 mm and > 7 mm) were cultured with three different concentration of PRP 3%, 5% and 10%. Expression of leukemia inhibitory factor (LIF), COX2 and P53, estrogen receptors (ERs) and progesterone receptors (PRs) genes were measured using quantitative real-time polymerase chain reaction (PCR). Protein expression levels of LIF, COX2 and p53 were evaluated using Western Blot method (WB). There was a significant decrease in the expression of PROA/b, ER2/b, LIF/b, COX2/b and P53/b genes in the RIF groups compared to the controls. Treatment with 5% and 10% PRP caused a significant increase in the gene expression of PRs, ERs, LIF/b, COX2/b and p53 in the RIF groups. Moreover, protein expression of COX2/b, LIF/b and p53/b increased following treatment with PRP in the RIF group with the endometrium thickness < 7 mm. PRP enhances expression of LIF, COX2, p53, ERs and PRs in the RIF patients with thin endometrium which may improve endometrium receptivity.

Angiogenic factor-driven improvement of refractory thin endometrium with autologous platelet-rich plasma intrauterine infusion in frozen embryo transfer cycles

Objective

A beneficial effect on endometrial thickness (EMT) and improvement of pregnancy outcome after intrauterine infusion of platelet-rich plasma (PRP) has been suggested. This study assessed the effect of intrauterine PRP infusion on live birth rate and obstetrical outcomes and analyzed cytokines that can potentially improve pregnancy outcomes through PRP.

Method

This study was a prospective cohort study conducted in a university hospital fertility center. The study included ninety-one patients who had a history of two or more failed in vitro fertilization (IVF) attempts and refractory thin endometrium that remained unresponsive after at least two conventional treatments for thin endometrium. Patients were treated with an intrauterine infusion of autologous PRP between days 7 and 14 of their hormone replacement therapy-frozen embryo transfer (HRT-FET) cycle. PRP was administered at 3-day intervals until their EMT reached 7mm. After a maximum of three PRP administrations, embryo transfer (ET) was performed. The primary outcome was the live birth rate. Secondary outcomes included the implantation rate and increase in EMT compared to the previous cycle. We compared the cytokines related to angiogenesis in a patient's whole blood (WB) and PRP by utilizing a commercial screening kit.

Results

The live birth rate in the PRP treatment cycle was 20.9% (19 of 91 patients), significantly superior to the previous cycle without PRP infusion (p < 0.001). The implantation rate was also significantly higher during the PRP treatment cycle (16.4%) compared to the previous cycle (3.1%) (p < 0.001). The mean EMT post-PRP treatment was 6.1 mm, showing a significant increase of 0.8 mm (p < 0.001). Nonetheless, an increase in EMT was also observed in the non-pregnancy group. No adverse effects were reported by patients treated with autologous PRP. Cytokine array analysis confirmed marked increases in well-known pro-angiogenic factors such as Ang-1, EGF, LAP (TGF-b1), MMP-8, PDGF-AA, and PDGF-AB/PDGF-BB.

Conclusion

Intrauterine PRP infusion offers a safe and effective treatment for patients with refractory thin endometrium and implantation failures. The angiogenic cytokines present in PRP are the primary drivers of this improvement.

The dual role of SUSD2 in cancer development

Sushi domain-containing protein 2 (SUSD2, also known as the complement control protein domain) is a representative and vital protein in the SUSD protein family involved in many physiological and pathological processes beyond complement regulation. Cancer is one of the leading causes of death worldwide. The complex role of SUSD2 in tumorigenesis and cancer progression has raised increasing concerns. Studies suggest that SUSD2 has different regulatory tendencies among different tumors and exerts its biological effects in a cancer type-specific manner; for instance, it has oncogenic effects on breast cancer, gastric cancer, and glioma and has tumor-suppression effects on lung cancer, bladder cancer, and colon cancer. Moreover, SUSD2 can be regulated by noncoding RNAs, its promoter methylation and other molecules, such as Galectin-1 (Gal-1), tropomyosin alpha-4 chain (TPM4), and p63. The therapeutic implications of targeting SUSD2 have already been preliminarily revealed in some malignancies, including melanoma, colon cancer, and breast cancer. This article reviews the role and regulatory mechanisms of SUSD2 in cancer development, as well as its structure and distribution. We hope that this review will advance the understanding of SUSD2 as a diagnostic and/or prognostic biomarker and provide new avenues for the development of novel cancer therapies.

Autologous PRP therapy for thin endometrium: A self-controlled case series study across menstrual cycles

OBJECTIVES

Thin endometrium (TE) compromises endometrial receptivity, often leading to implantation failure and lower clinical pregnancy rates. As autologous platelet-rich plasma (PRP) emerges as a potential remedy, the present study focused on its therapeutic effects on TE in infertile women who underwent frozen embryo transfer.

STUDY DESIGN

Patients with TE who underwent frozen embryo transfer treatment in our hospital were included. To diminish individual variability, a self-controlled series approach was used. Two menstrual study cycles were arranged for each participant before the actual embryo transfer cycle; PRP treatment was conducted in the second cycle. Key metrics analyzed included endometrial thickness and the expression of specific endometrial biomarkers including HOXA-10, Ki67, and αvβ3 integrin. Transvaginal ultrasound was employed to measure endometrial thickness on Days 11 and 14, and an endometrial biopsy was conducted on progesterone Day 5 of the first two cycles. Pregnancy outcomes were observed after the embryo transfer cycle.

RESULTS

PRP treatment significantly increased the median endometrial thickness, from 5.8 mm to 6.5 mm (P = 0.0066). Additionally, PRP treatment resulted in a statistically significant increase in the H-score for all endometrial markers. Importantly, during the subsequent embryo transfer cycle with PRP treatment, two patients successfully achieved pregnancies, both culminating in live births.

CONCLUSIONS

These findings emphasize the potential of PRP in improving endometrial conditions, especially for individuals grappling with thin endometrium issues, as underscored by this self-comparison methodology.

Platelet-rich plasma infusion as an adjunct treatment for persistent thin lining in frozen embryo transfer cycles: first US experience report

PURPOSE

To study effect of intrauterine infusion of platelet-rich plasma (PRP) on endometrial growth in the setting of thin endometrial lining in patients with prior cancelled or failed frozen embryo transfer (FET) cycles.

MATERIALS AND METHODS

Single-arm cohort study of forty-six patients (51 cycles) with endometrial lining thickness (EMT) < 6 mm in prior cancelled or failed FET cycles requesting intrauterine PRP treatment in upcoming FET cycle. The primary outcomes were final EMT in FET cycle and change in EMT after PRP. The secondary outcomes were overall pregnancy rate, clinical pregnancy rate, miscarriage rate, ongoing pregnancy, and live birth rates.

RESULTS

The mean pre-PRP EMT in all FET cycles was 4.0 ± 1.1 mm, and mean post-PRP EMT (final) was 7.1 ± 1.0 mm. Of 51 cycles, 33 (64.7%) reached ≥ 7 mm after PRP administration. There was a significant difference between pre-PRP EMT and post-PRP EMT in all FET cycles, with mean difference of 3.0 ± 1.5 mm. Three cycles were cancelled for failure to reach adequate lining. Total pregnancy rate was 72.9% in our cohort of 48 cycles that proceeded to transfer. Clinical pregnancy rate was 54.2% (26/48 FET cycles); clinical miscarriage rate was 14.3% (5/35 pregnancies). Twenty six women had live birth (18 with EMT ≥ 7 mm and 8 with EMT < 7 mm). Response to PRP was not correlated with any pre-cycle characteristics.

CONCLUSION

We demonstrate a significant improvement in lining thickness and pregnancy rates in this challenging cohort of women after PRP infusion, with no adverse events. Cost-effectiveness of PRP with benefits and alternatives should be carefully considered.

S100A8/A9 promotes endometrial fibrosis via regulating RAGE/JAK2/STAT3 signaling pathway

Intrauterine adhesion (IUA) is characterized by endometrial fibrosis. S100A8/A9 plays an important role in inflammation and fibroblast activation. However, the role of S100A8/A9 in IUA remains unclear. In this study, we collect normal and IUA endometrium to verify the expression of S100A8/A9. Human endometrial stromal cells (hEnSCs) are isolated to evaluate fibrosis progression after S100A8/A9 treatment. A porcine IUA model is established by electrocautery injury to confirm the therapeutic effect of menstrual blood-derived stromal cells (MenSCs) on IUA. Our study reveals increased S100A8/A9 expression in IUA endometrium. S100A8/A9 significantly enhances hEnSCs proliferation and upregulates fibrosis-related and inflammation-associated markers. Furthermore, S100A8/A9 induces hEnSCs fibrosis through the RAGE-JAK2-STAT3 pathway. Transplantation of MenSCs in a porcine IUA model notably enhances angiogenesis, mitigates endometrial fibrosis and downregulates S100A8/A9 expression. In summary, S100A8/A9 induces hEnSCs fibrosis via the RAGE-JAK2-STAT3 pathway, and MenSCs exhibit marked effects on endometrial restoration in the porcine IUA model.

Value of Intrauterine Autologous Platelet-Rich Plasma Therapy on Endometrial Receptivity: A Literature Review

Endometrial receptivity is an important factor that influences embryo implantation. Thus, it is important to identify an applicable approach to improve endometrial receptivity in women undergoing assisted reproductive technology. Recently, growing evidence has indicated that intrauterine platelet-rich plasma (PRP) infusion is an effective method to obtain a satisfactory reproductive outcome by increasing endometrial thickness and improving endometrial receptivity. Therefore, the present review aims to outline the possible mechanisms of PRP on endometrial receptivity and summarize the present literature on the effects of PRP therapy in improving endometrial receptivity.

Platelet-rich fibrin improves repair and regeneration of damaged endometrium in rats

Purpose

Intrauterine adhesion (IUA) is the most common cause of uterine infertility. This study aims to evaluate whether platelet-rich fibrin (PRF) treatment can stimulate damaged endometrium regeneration in rats.

Methods

First, hematoxylin and eosin (HE) staining, scanning and transmission electron microscopy, and ELISAs were used to evaluate the microstructure of PRF. Then, mechanical damage was used to establish an IUA rat model. A total of 40 SD female rats were randomized to three groups: PRF transplantation group, IUA group, and sham group. Rats were sacrificed at 3, 7, and 14 days and uteruses were obtained for further analysis. Finally, functional and histological recovery of the damaged endometrium was analyzed by pregnancy test, HE staining, Masson's staining, and immunohistochemistry.

Results

PRF has two distinct zones, platelets and fibrin zone. Long and narrow fibrin fibers interconnected with each other and formed a three-dimensional, flexible, and elastic structure; platelet aggregates were trapped in fibrin fibers, and each platelet is associated with several fibrin fibers. PRF exudates promoted endometrial stromal cell proliferation and migration in vitro. PRF transplantation was beneficial for maintaining uterine structure, promoting endometrial luminal epithelium and endometrial gland regeneration, and decreasing fibrotic areas in vivo.

Conclusion

Intrauterine administration of PRF was demonstrated to be effective in preventing IUA and stimulating damaged endometrium regeneration in rats. This study not only provided a promising method for its potential in endometrial regeneration in women who suffer from uterine infertility but also may prevent IUA after intrauterine surgery in clinical cases.

Treatment options for endometrial hypoproliferation

PURPOSE OF REVIEW

Endometrial hypoproliferation refers to the failure of the endometrium to reach optimal thickness during fresh or frozen embryo transfer cycles in women undergoing infertility treatment with in-vitro fertilization (IVF). This review discusses the treatment options for endometrial hypoproliferation.

RECENT FINDINGS

Apart from factors related to the embryo quality, ultrasonographic findings associated with the endometrium, such as endometrial thickness, endometrial pattern and subendometrial blood flow, are considered key factors associated with the outcome of assisted reproductive treatment. To date, a consensus has not been reached regarding the definition of thin endometrium, while thresholds of 6, 7 or 8 mm have been used in the literature. Strategies to increase endometrial thickness can be reviewed in three groups: endocrine approaches, vitamins & supplements, and new experimental therapeutic interventions. Some of the recently introduced experimental therapeutic interventions such as platelet-rich plasma injection, stem cell treatment and tissue bioengineering are exciting potential therapies that need to be further studied.

SUMMARY

Despite a large number of publications on the topic, diagnosing and treating endometrial hypoproliferation remains a challenge. Well designed studies are needed to establish a widely accepted endometrial thickness cut-off value below which endometrial hypoproliferation is diagnosed and to generate meaningful data that would allow an evidence-based discussion of available therapeutic options with patients.

Menstrual Blood-Derived Mesenchymal Stem Cells Encapsulated in Autologous Platelet-Rich Gel Facilitate Rotator Cuff Healing in a Rabbit Model of Chronic Tears

BACKGROUND

Successful management of chronic rotator cuff (RC) tears remains a challenge owing to its limited intrinsic healing capacity and unsatisfactory failure rate. Menstrual blood-derived mesenchymal stem cells (MenSCs) have the potential to differentiate into the chondrogenic or osteogenic lineage. Autologous platelet-rich gel (APG), a gel material derived from platelet-rich plasma (PRP), can be applied as a carrier system for cell delivery and also as a releasing system for endogenous growth factors.

PURPOSE

To investigate the effect of human MenSCs encapsulated in APG (MenSCs@APG) on the healing of chronic RC tears in a rabbit model.

STUDY DESIGN

Controlled laboratory study.

METHODS

After evaluation of the effect of PRP on MenSC proliferation or differentiation, the stem cells were encapsulated in APG for in vivo injection. Supraspinatus tenotomy from the right greater tuberosity was performed on 45 New Zealand White rabbits. After 6 weeks, these rabbits were randomly allocated to 3 supplemental treatments during supraspinatus repair: saline injection (control [CTL] group), APG injection (APG group), and MenSCs@APG injection (MenSCs@APG group). At week 18, these rabbits were sacrificed to harvest the humerus-supraspinatus tendon complexes for micro-computed tomography (CT), histological evaluation, tensile test, and MenSC tracking.

RESULTS

In vitro results showed that APG can stimulate MenSC proliferation and enhance chondrogenic or osteogenic differentiation. In vivo results showed that APG can act as a carrier for delivering MenSCs into the healing site, and also as a stimulator for enhancing the in vivo performance of MenSCs. Micro-CT showed that bone volume/total volume and trabecular thickness of the new bone in the MenSCs@APG group presented significantly larger values than those of the APG or CTL group (P < .05 for all). Histologically, compared with the CTL or APG group, significantly more mature fibrocartilage regenerated at the healing site in the MenSCs@APG group. A large number of human nuclei-stained cells were observed in the MenSCs@APG group, presenting a similar appearance to fibrochondrocytes or osteocytes. Biomechanically, the MenSCs@APG group showed significantly higher failure load and stiffness than the APG or CTL group (P < .05 for all).

CONCLUSION

Human MenSCs@APG facilitated RC healing in a rabbit model of chronic tears.

CLINICAL RELEVANCE

Autogenous MenSCs@APG may be a new stem cell-based therapy for augmenting RC healing in the clinic.

PDGFBB improved the biological function of menstrual blood-derived stromal cells and the anti-fibrotic properties of exosomes

BACKGROUND

Intrauterine adhesion (IUA) is a reproductive dysfunction disease characterized by endometrial fibrosis, with limited therapeutic options and poor prognosis. Our previous studies confirmed that menstrual blood-derived stromal cells (MenSCs) effectively attenuated endometrial fibrosis in an animal model of IUA mainly through exosomes. This therapeutic effect can be enhanced by platelet-rich plasma (PRP), in which PDGFBB is an abundant growth factor. Therefore, we aimed to compare the effects of PRP and PDGFBB on the biological activities of MenSCs in vitro, and to further investigate the molecular mechanism of MenSCs-derived exosomes in alleviating endometrial fibrosis.

METHODS

MenSCs were isolated for in vitro functional assays to examine the viability, migration, and stemness of MenSCs. Endometrial stromal cells (EndoSCs) were treated with 50 ug/ml of MenSCs-derived exosomes, obtained by differential ultracentrifugation extraction. The molecular mechanisms by which PDGFBB improves MenSCs and exosomes alleviate EndoSCs fibrosis were then explored using immunofluorescence, western blot, and co-immunoprecipitation.

RESULTS

Both 100 ng/ml PDGFBB and 10% activated PRP promoted the proliferation, increased the S phase of cell cycle, and inhibited apoptosis of MenSCs in vitro. Compared with PRP, PDGFBB significantly promoted MenSCs migration. All of these effects were inhibited by sorafenib, a PDGFR-β inhibitor. PRP and PDGFBB activated AKT/NF-κB signaling pathway in MenSCs and increased the expression of P65 and OCT4. Moreover, pretreatment of PDGFBB did not increase the secretion of MenSCs but significantly increased the anti-fibrosis effects of MenSCs-derived exosomes on IUA-EndoSCs. MenSCs-derived exosomes attenuated SMAD3 phosphorylation and increased YAP ubiquitination, which reduced the binding of YAP/SMAD3. Pretreatment with PDGFBB amplified this effect.

CONCLUSIONS

In summary, PDGFBB could improve the biological functions of MenSCs via AKT/NF-κB signaling pathway, including viability, migration, and stemness. Our results indicated that PDGFBB amplified MenSCs-derived exosomes to attenuate endometrial fibrosis by inhibiting YAP activity, revealing a novel mechanism by which PRP enhanced the ability of MenSCs to repair tissue injury and providing a potential option for improving stem cell efficacy in IUA.

The differentiation and generation of glucose-sensitive beta like-cells from menstrual blood-derived stem cells using an optimized differentiation medium with platelet-rich plasma (PRP)

Regarding their reversible damage of insulin-producing cells (IPCs) and the inefficiency of treatment methods for type 1 diabetes mellitus (T1DM), scientists decided to produce IPCs from an unlimited source of cells. But the production of these cells is constantly faced with problems such as low differentiation efficiency in cell therapy and regenerative medicine. This study provided an ideal differentiation medium enriched with plasma-rich platelet (PRP) delivery to produce IPCs from menstrual blood-derived stem cells (MenSCs). We compared them with and without PRP differentiation medium. MenSCs were then cultured in two experimental groups: with/without PRP differentiation medium and a control group (undifferentiated MenSCs). After 18 days, differentiated cells were analyzed for expression of pancreatic gene markers by real-time PCR. Immunocytochemical staining was used to detect the presence of insulin and Pdx-1 in the differentiated cells, and insulin and C-peptide secretion response to glucose were tested by ELISA. Finally, the morphology of differentiated cells was examined by an inverted microscope. In vitro studies showed that MenSCs differentiated in the PRP differentiation medium had strong properties of IPCs such as pancreatic islet-like structure. The expression of pancreatic markers at both RNA and protein levels showed that the differentiation efficiency was higher in the PRP differentiation medium. In both experimental groups, the differentiated cells were functional and secreted C-peptide and insulin on glucose stimulation, but the secretion of C-peptide and insulin in the PRP group was higher than those cultured in the without PRP differentiation medium. Our findings showed that using of PRP enriched differentiation medium can promote the differentiation of MenSCs into IPCs compared to the without PRP culture group. Therefore, the use of PRP into differentiation media can be proposed as a new approach to producing IPCs from MenSCs and used in cell-based therapies for T1DM.

Transcription factor cellular promoter 2 is required for upstream binding protein 1 -mediated angiogenesis

OBJECTIVE

Angiogenesis is a key process of repairing tissue damage, and it is regulated by the delicate balance between anti-angiogenesis factors. In the present study, we investigate whether transcription factor cellular promoter 2 (TFCP2) is required for upstream binding protein 1 (UBP1)-mediated angiogenesis.

METHODS

Levels of UBP1 and TFCP2 in human umbilical vein endothelial cells (HUVECs) are detected by quantitative polymerase chain reaction (q-PCR) and Western blotting (WB). Effects of UBP1 on angiogenesis and migration are detected by tube-like network formation on matrigel assay and scratch assay. The interaction between UBP1 and TFCP2 is predicted and verified by STRING and Co-immunoprecipitation (Co-IP).

RESULTS

Firstly, the UBP1 expression level was up-regulated in the stimuli of vascular endothelial growth factor (VEGF) in HUVECs, and the knockdown of UBP1 inhibited angiogenesis and migration of HUVECs. Then, UBP1 interacted with TFCP2. Besides, the TFCP2 expression level was up-regulated in VEGF-stimulated HUVECs. Furthermore, knockdown of TFCP2 inhibited angiogenesis and migration in VEGF-stimulated HUVECs, and down-regulation of UBP1 enhanced the inhibition.

CONCLUSION

TFCP2 also plays a key role in UBP1 mediated angiogenesis of HUVECs stimulated by VEGF. These findings will provide a new theoretical basis for the treatment of angiogenic diseases.

Endometrial cell-derived conditioned medium in combination with platelet-rich plasma promotes the development of mouse ovarian follicles

Fertility preservation is one of the most important issues in assisted reproductive technology. Previous studies have shown that cytokines and growth factors can improve follicle growth. The endometrial stromal cells secrete various factors that are involved in maintaining the integrity of uterine and epithelial secretory function. The platelet-rich plasma contains a large assembly of platelets suspended in plasma that successfully improves the viability and growth of various cell lines. This work aimed to investigate the influences of conditioned medium (CM) and platelet-rich plasma (PRP) on the development of ovarian follicles in infertile mice due to cyclophosphamide (CYC) exposure. In this study, 65 healthy BALB/c female mice (∼28-30 g and 6-8 weeks old) in five groups were studied. Immunohistochemistry (IHC) was used to detect growth differentiation factor 9 (GDF9)-positive cells. The mRNA expression levels of SMAD1, SMAD2, and BMP15 was assessed using reverse transcription-polymerase chain reaction (RT-PCR) method. The expression levels of SMAD1, GDF9, BMP15, and SMAD2 in the CM+PRP group was significantly more than in the CM and PRP groups. In addition, live birth occurred in the CM+PRP group. Treatment with CM+PRP in infertile mice due to Cy exposure increased fertility and live-birth rate. In general, our study suggested that the CM and PRP combination could improve the growth of mice ovarian follicles in vivo.

Enhancement of Immunosuppressive Activity of Mesenchymal Stromal Cells by Platelet-Derived Factors is Accompanied by Apoptotic Priming

The pro-inflammatory phase of bone healing, initiated by platelet activation and eventually hematoma formation, impacts bone marrow mesenchymal stromal cells (MSCs) in unknown ways. Here, we created platelet-rich plasma (PRP) hydrogels to study how platelet-derived factors modulate functional properties of encapsulated MSCs in comparison to a non-inflammatory fibrin (FBR) hydrogel environment. MSCs were isolated from human bone marrow, while PRP was collected from pooled apheresis thrombocyte concentrates and used for hydrogel preparation. After their encapsulation in hydrogels for 72 h, retrieved MSCs were analyzed for immunomodulatory activities, apoptosis, stem cell properties, senescence, CD9+, CD63+ and CD81+ extracellular vesicle (EV) release, and metabolism-related changes. PRP-hydrogels stimulated immunosuppressive functions of MSCs, along with their upregulated susceptibility to cell death in communication with PBMCs and augmented caspase 3/7 activity. We found impaired clonal growth and cell cycle progression, and more pronounced β-galactosidase activity as well as accumulation of LC3-II-positive vacuoles in PRP-MSCs. Stimuli derived from PRP-hydrogels upregulated AKT and reduced mTOR phosphorylation in MSCs, which suggests an initiation of survival-related processes. Our results showed that PRP-hydrogels might represent a metabolically stressful environment, inducing acidification of MSCs, reducing polarization of the mitochondrial membrane and increasing lipid accumulation. These features were not detected in FBR-MSCs, which showed reduced CD63+ and CD81+ EV production and maintained clonogenicity. Our data revealed that PRP-derived hematoma components cause metabolic adaptation of MSCs followed by increased immune regulatory functions. For the first time, we showed that PRP stimuli represent a survival challenge and “apoptotic priming” that are detrimental for stem cell-like growth of MSCs and important for their therapeutic consideration.

Graphical Abstract

Conductance Artery Wall Layers and Their Respective Roles in the Clearance Functions

Evolutionary organization of the arterial wall into layers occurred concomitantly with the emergence of a highly muscularized, pressurized arterial system that facilitates outward hydraulic conductance and mass transport of soluble substances across the arterial wall. Although colliding circulating cells disperse potential energy within the arterial wall, the different layers counteract this effect: (1) the endothelium ensures a partial barrier function; (2) the media comprises smooth muscle cells capable of endocytosis/phagocytosis; (3) the outer adventitia and perivascular adipocytic tissue are the final receptacles of convected substances. While the endothelium forms a physical and a biochemical barrier, the medial layer is avascular, relying on the specific permeability properties of the endothelium for metabolic support. Different components of the media interact with convected molecules: medial smooth muscle cells take up numerous molecules via scavenger receptors and are capable of phagocytosis of macro/micro particles. The outer layers-the highly microvascularized innervated adventitia and perivascular adipose tissue-are also involved in the clearance functions of the media: the adventitia is the seat of immune response development, inward angiogenesis, macromolecular lymphatic drainage, and neuronal stimulation. Consequently, the clearance functions of the arterial wall are physiologically essential, but also may favor the development of arterial wall pathologies. This review describes how the walls of large conductance arteries have acquired physiological clearance functions, how this is determined by the attributes of the endothelial barrier, governed by endocytic and phagocytic capacities of smooth muscle cells, impacting adventitial functions, and the role of these clearance functions in arterial wall diseases.

The Combined Use of Platelet-Rich Plasma Clot Releasate and Allogeneic Human Umbilical Cord Mesenchymal Stem Cells Rescue Glucocorticoid-Induced Osteonecrosis of the Femoral Head

Glucocorticoid-induced osteonecrosis of the femoral head (ONFH) is a refractory disease. The treatment options for ONFH, especially nonsurgical ones, merit further investigation. To evaluate the combinatorial therapeutic effects of platelet-rich plasma clot releasate (PRCR) and umbilical cord mesenchymal stem cells (UC-MSCs) on glucocorticoid-induced ONFH, a dexamethasone (DEX)-treated cell model and a high-dose methylprednisolone (MPS)-treated rat model were established. Cell counting kit-8 (CCK-8) assay was performed in vitro to determine the optimum dosage of PRCR for UC-MSC viability. The effects of PRCR, UC-MSCs, and PRCR + UC-MSCs on cell viability, apoptosis, migration, and differentiation capacities of DEX-treated bone marrow mesenchymal stem cells (BMSCs) and human umbilical vein endothelial cell (HUVECs) were explored via Transwell assays. Western blotting was conducted to evaluate the expression levels of RUNX2, VEGF, caspase-3, and Bcl-2 in the coculture systems. Ultrasound-guided intra-articular PRCR, UC-MSCs, and PRCR + UC-MSC injections were performed on the ONFH model rats. Microcomputed tomography, histological and immunohistochemical analyses, tartrate-resistant acid phosphatase (TRAP) staining, and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining were used to assess the therapeutic effects of PRCR and UC-MSCs on bone loss and necrosis induced by high-dose MPS. Results of this study revealed that the in vitro application of PRCR, UC-MSCs, and PRCR + UC-MSCs reversed the impaired proliferation and migration capacities and resisted apoptosis of BMSCs and HUVECs induced by DEX. Moreover, the PRCR and UC-MSC application significantly improved the alkaline phosphatase (ALP) and alizarin red (ALR) staining of BMSCs and tube formation capacity of HUVECs and promoted the protein expression of RUNX2 in BMSCs and VEGF in HUVECs. Similarly, in the ONFH rat model, the intra-articular injection of UC-MSCs and PRCR improved the subchondral bone mass parameters; promoted the expression of ALP, RUNX2, and VEGF; suppressed osteoclast overactivity; and resisted cell apoptosis. The combination of PRCR and UC-MSCs shows promising therapeutic effects in treating glucocorticoid-induced ONFH. The current study provides important information on intra-articular therapy, paving the way for the clinical management of ONFH in the future.

Therapeutic effect of platelet-rich plasma on glucocorticoid-induced rat bone marrow mesenchymal stem cells in vitro

BACKGROUND

Glucocorticoid-induced osteonecrosis of the femoral head (GIONFH) is a progressive and disabling disease caused by long-term or high-dose glucocorticoid use. Decreased osteogenesis and proliferation of bone marrow mesenchymal stem cells (BMSCs) are the main pathogenesis of GIONFH. Platelet-rich plasma (PRP) has been shown to play a promising role in bone regeneration. However, the effects of PRP on glucocorticoid-induced BMSCs inhibition remains elusive. The objective of this study was to explore whether PRP could improve the in vitro biological activities of BMSCs inhibited by high-dose glucocorticoid in vitro.

METHODS

In this study, a dexamethasone (Dex)-induced in vitro cell model was established. The effects of PRP on proliferation, migration, cell cycle and apoptosis of rat BMSCs induced with high-dose Dex compared to BMSC_CTRL, using CCK-8 assay, transwell, flow cytometry and TUNEL assay, respectively. We further performed the alkaline phosphatase (ALP) and alizarin red (ALR) staining to explore the influence of PRP on osteogenic differentiation. Western Blot was used to detect the expression of Bcl-2, Caspase-3, RUNX2 apoptosis, and osteogenic-related proteins.

RESULTS

We observed increased apoptosis rate and Caspase-3 expression, and the decreased migration and osteogenic differentiation, and down-regulation of RUNX-2 and Bcl-2 expression in Dex-induced BMSCs. PRP could reverse these inhibitory effects of Dex, and enhance the BMSCs proliferation, migration, and osteogenic ability in vitro.

CONCLUSION

Our vitro study showed that PRP significantly protected BMSCs from Dex-induced apoptosis, and further promoted BMSCs proliferation, migration, and osteogenic differentiation. This study provides a scientific basis for the prevention and treatment of GIONFH with PRP. Meanwhile, it also lays the foundation for the application of PRP in other musculoskeletal diseases.

Activated Human Umbilical Cord Blood Platelet-Rich Plasma Enhances the Beneficial Effects of Human Umbilical Cord Mesenchymal Stem Cells in Chemotherapy-Induced POF Rats

Saving the ovarian function of premature ovarian failure (POF) patients undergoing chemotherapy is an important problem in the field of reproductive medicine. At present, human umbilical cord mesenchymal stem cells (HucMSCs) have been used in the treatment of POF, but the effect is still not optimal. The purpose of this study was to determine whether human umbilical cord blood platelet-rich plasma (ucPRP) enhances the beneficial effects of HucMSCs in the treatment of POF. First, we observed the effects of changes in the biological activity of ucPRP on HucMSCs in vitro. Subsequently, we tracked the distribution and function of the HucMSCs in POF rats, and the rats' estrus cycle and serum sex hormones, follicular development, ovarian angiogenesis, ovarian granulosa cell proliferation, and apoptosis were assessed. The results of the study showed that the addition of ucPRP in vitro accelerates proliferation and reduces apoptosis of the HucMSCs while upregulating the stemness gene of the HucMSCs. The combined transplantation of HucMSCs and ucPRP resulted in more stem cells being retained in the ovaries of POF rats, the estrus cycle of the POF rats being restored, the levels of serum E2, AMH, and FSH improving, and damaged follicles beginning to grow. Finally, we confirmed that the potential mechanism of the combination of HucMSCs and ucPRP to rescue the ovarian function of POF rats is to promote ovarian angiogenesis and to promote the proliferation and reduce the apoptosis of ovarian granulosa cells. The upregulation of AMH and FHSR expression and the downregulation of caspase-3 expression in granulosa cells are potential mechanisms for the recovery of ovarian function. Our research results suggest that the combined application of HucMSCs and ucPRP is a safe and efficient transplantation program for the treatment of POF, thus providing a reliable experimental basis for the clinical application of stem cell therapy in POF.

Hydrogel, a novel therapeutic and delivery strategy, in the treatment of intrauterine adhesions

Intrauterine adhesions (IUAs) are caused by damage to the underlying lining of the endometrium. They' re related to disorder of endometrial repair. In recent years, hydrogels with controllable biological activity have been widely used for treating IUAs. They encapsulate estrogen, cytokines, cells, or exosomes, forming a delivery system to release therapeutic components for the treatment of IUAs. In addition, the hydrogel acting as a barrier can be degraded in the body automatically, reducing the risk of infection caused by secondary surgeries. In this review, we summarize the recent progress of hydrogels and their application in IUAs as both a novel alternative therapeutic and an artificial delivery strategy.

Hierarchical cluster analysis in the study of the effect of cytokine expression patterns on endometrial repair and receptivity after hysteroscopic adhesiolysis

Background

In a previous study, we reported that amnion promotes endometrial cell growth by regulating cytokines. In this study, hierarchical cluster analysis enabled the evaluation of cytokine expression changes after amnion treatment to be explored by cluster patterns. The role of IL1B on endometrial repair and receptivity was revealed.

Methods

A total of 30 patients were recruited in this clinical trial (NCT02496052) of hysteroscopic adhesiolysis. They were randomly allocated into an amnion grafts group (amnion group) and a control group. After hysteroscopic adhesiolysis, a Foley catheter covered with a sterilized freeze-dried amnion graft was inserted into the uterine cavity of the participants in the amnion group, whereas for the control group, a Foley catheter without amnion graft was inserted. After surgery, patient follow-up was done for a year. Uterine exudates were collected every day for seven days after surgery, and analyzed by enzyme-linked immunosorbent assays. Hierarchical cluster analysis was performed to compare expression patterns of each cytokine. Single-gene gene set enrichment analysis and differentially expressed genes enrichment analysis of IL1B were performed using NCBI GEO (N=151) to evaluate its potential mechanisms and impact on endometrial receptivity.

Results

Compared to the control group, cytokine expression patterns of the amnion group revealed significant stratifications, which were highly correlated with the expression levels of IL1B on the sixth to seventh day after surgery, improving the pregnant rate. Wilcoxon test revealed significantly low expression levels of IL1B in the reduced endometrial receptivity group compared to the normal group. Moreover, gene set enrichment analysis showed that lysosomes, cell cycle, and calcium signaling pathways were associated with the biological processes in which IL1B plays a role. Screening and enrichment analyses of differentially expressed genes further verified the mechanisms of action of IL1B on endometrial repair and receptivity recovery.

Conclusions

Amnion promotes endometrial repair and receptivity by altering the expression levels and patterns of IL1B. Furthermore, by affecting lysosomal, cell cycle, and calcium signaling pathways, IL1B may be one of the factors involved in endometrial repair and receptivity recovery.

Concentrated exosomes from menstrual blood-derived stromal cells improves ovarian activity in a rat model of premature ovarian insufficiency

Background

Premature ovarian insufficiency (POI) is one of the major causes of infertility. We previously demonstrated that transplantation of menstrual blood-derived stromal cells (MenSCs) effectively improved ovarian function in a murine model of POI. Recent studies indicated that mesenchymal stem cell-derived exosomes were important components in tissue repair. In this study, we investigated the therapeutic effects of MenSCs-derived exosomes (MenSCs-Exos) in a rat model of POI and its mechanism in restoring ovulation.

Methods

Ovaries of 4.5-day-old Sprague Dawley rats (SD rats) were cultured in vitro to evaluate the effects of MenSCs-Exos exposure on early follicle development. Furthermore, POI in rats was induced by intraperitoneal administration of 4-vinylcyclohexene diepoxide (VCD). Forty-eight POI rats were randomly assigned to four groups, each receiving a different treatment: PBS, MenSCs, MenSCs-Exos, and Exo-free culture supernatant of MenSCs. Estrous cyclicity, ovarian morphology, follicle dynamics, serum hormones, pregnancy outcomes, and molecular changes were investigated.

Results

Exposure to MenSCs-Exos promoted the proliferation of granulosa cells in primordial and primary follicles in vitro and increased the expression of early follicle markers Deleted In Azoospermia Like (DAZL) and Forkhead Box L2 (FOXL2) while inhibiting follicle apoptosis. In vivo, MenSCs-Exos transplantation effectively promoted follicle development in the rat model of POI and restored the estrous cyclicity and serum sex hormone levels, followed by improving the live birth outcome. In addition, transplantation of MenSCs-Exos regulated the composition of the ovarian extracellular matrix and accelerated the recruitment of dormant follicles in the ovarian cortex and increased proliferation of granulosa cells in these follicles.

Conclusion

MenSCs-Exos markedly promoted follicle development in vitro and in vivo and restored fertility in POI rats, suggesting a restorative effect on ovarian functions. The therapeutic effect of MenSCs-Exos transplantation was sustainable, consistent with that of MenSCs transplantation. Our results suggested that MenSCs-Exos transplantation may be a promising cell-free bioresource in the treatment of POI.

Intraovarian insertion of autologous platelet growth factors as cell-free concentrate: Fertility recovery and first unassisted conception with term delivery at age over 40

Background

The use of autologous platelet-rich plasma as an ovarian treatment has not been standardized and remains controversial.

Case Presentation

A 41½-year old woman with diminished ovarian reserve (serum anti- Müllerian hormone = 0.163 mg/mL) and a history of 10 unsuccessful in vitro fertilization cycles presented for reproductive endocrinology consult. She and her partner declined donor oocyte in vitro fertilization. They were both in good general health and laboratory tests were unremarkable, except for mild thrombocytosis (platelets = 386K; normal range 150-379K) discovered in the female. The patient underwent intraovarian injection of fresh platelet-derived growth factor concentrate administered as an enriched cell-free substrate. Serum anti- Müllerian hormone increased by 115% within 6 wks of treatment. Spontaneous ovulation occurred the month after injection and subsequently the serum human chorionic gonadotropin was noted at 804 mIU/mL. Following an uneventful obstetrical course, a male infant was delivered at term without complication.

Conclusion

This is the first description of intraovarian injection of enriched platelet-derived growth factors followed by unassisted pregnancy and live birth. As a refinement of conventional ovarian platelet-rich plasma therapy, this procedure may be particularly valuable for refractory cases where prognosis for pregnancy appears especially bleak. A putative role for thrombocytosis is also viewed in parallel with mechanisms of action as advanced earlier. With continued experience in ovarian application of autologous platelet growth factors, additional research will evaluate laboratory protocol/sample preparation, injection technique, and patient selection.

Chondrogenic differentiation of Wharton's Jelly mesenchymal stem cells on silk spidroin-fibroin mix scaffold supplemented with L-ascorbic acid and platelet rich plasma

In this research, hWJ-MSCs were grown on silk scaffolds and induced towards chondrogenesis by supplementation with L-ascorbic acid (LAA) or platelet rich plasma (PRP). Silk scaffolds were fabricated with salt leaching method by mixing silk fibroin (SF) with silk spidroin (SS). The silk fibroin was obtained from Bombyx mori cocoon that had been degummed, and the silk spidroin was obtained from wild-type spider Argiope appensa. The effect of scaffold composition and inducer on cell proliferation was observed through MTT assay. The most optimal treatment then continued to be used to induce hWJ-MSC towards chondrogenic differentiation for 7 and 21 days. Scaffolds characterization showed that the scaffolds produced had 3D structure with interconnected pores, and all were biocompatible with hWJ-MSCs. Scaffold with the addition of 10% SS + 90% SF showed higher compressive strength and better pore interconnectivity in comparison to 100% silk fibroin scaffold. After 48 h, cells seeded on scaffold with spidroin and fibroin mix had flattened morphology in comparison to silk fibroin scaffold which appeared to be more rounded on the scaffold surface. Scaffold with 10% (w/w) of silk spidroin (SS) + 90% (w/w) of silk fibroin (SF) was the most optimal composition for cell proliferation. Immunocytochemistry of integrin β1 and RGD sequence, showed that scaffold with SS 10% provide better cell attachment with the presence of RGD sequence from the spidroin silk which could explain the higher cell proliferation than SF100% scaffold. Based on Alcian Blue staining and Collagen Type II immunocytochemistry (ICC), cells grown on 10% SS + 90% SF scaffold with 10% PRP supplementation were the most optimal to support chondrogenesis of hWJ-MSCs. These results showed that the addition of spidroin silk from A. appensa. had impact on scaffold compressive strength and chondrogenic differentiation of hWJ-MSC and had the potential for further development of bio-based material scaffold in cartilage tissue engineering.

Evaluation of the Effect of Plasma from Patients with Trophic Ulcers on the Function of Dermal Fibroblasts, Mesenchymal Stem Cells, and Endothelial Cells

We studied the effect of platelet lysate and platelet-poor plasma from patients with trophic ulcers with and without type 2 diabetes mellitus on proliferation, migration, and apoptosis of human dermal fibroblast, mesenchymal stem cells, and endothelial cells. It is shown that plasma obtained from patients with type 2 diabetes mellitus produced inhibitory effects.

Menstrual blood-derived stem cells: toward therapeutic mechanisms, novel strategies, and future perspectives in the treatment of diseases

Menstrual blood-derived stem cells (MenSCs) have great potential in the treatment of various diseases. As a novel type of mesenchymal stem cells (MSCs), MenSCs have attracted more interest due to their therapeutic effects in both animal models and clinical trials. Here, we described the differentiation, immunomodulation, paracrine, homing, and engraftment mechanisms of MenSCs. These include differentiation into targeting cells, immunomodulation with various immune cells, the paracrine effect on secreting cytokines, and homing and engraftment into injured sites. To better conduct MenSC-based therapy, some novel hotspots were proposed such as CRISPR (clustered regularly interspaced short palindromic repeats)/cas9-mediated gene modification, exosomes for cell-free therapy, single-cell RNA sequence for precision medicine, engineered MenSC-based therapy for the delivery platform, and stem cell niches for improving microenvironment. Subsequently, current challenges were elaborated on, with regard to age of donor, dose of MenSCs, transplantation route, and monitoring time. The management of clinical research with respect to MenSC-based therapy in diseases will become more normative and strict. Thus, a more comprehensive horizon should be considered that includes a combination of traditional solutions and novel strategies. In summary, MenSC-based treatment has a great potential in treating diseases through diverse strategies, and more therapeutic mechanisms and novel strategies need to be elucidated for future regenerative medicine and clinical applications.

Therapeutic options and drug delivery strategies for the prevention of intrauterine adhesions

Intrauterine adhesions (IUAs) are bands of fibrous tissue that form in the endometrial cavity and associated with the increased risk of abnormal menstruation, recurrent pregnancy loss, secondary infertility, and pregnancy complications. Physical barriers, including intrauterine device and hydrogel, were clinical available to prevent the post-operational IUAs. But physically separation of the injured endometrium relies on the own limited healing power and often ends with recurrence. In recent years, the mechanisms driving IUAs treatment has validated the application of hormones, and further stem cell therapy has also led to the development of novel therapeutic agents with promising efficacy in pre-clinical and initial clinical studies. Still, it is challenging to delivery the therpaeutic factors to the injured uterus. Herein, in this review, we discuss the traditional intervention methods for the prevention of IUAs, as well as novel therapeutics and delivery strategies that will most likely change the treatment paradigms for better clinical outcomes. The combination strategy that using physical barriers as the delivery carriers for therapeutics might provide new alternatives for the prevention of IUAs.

Platelet-rich plasma improves therapeutic effects of menstrual blood-derived stromal cells in rat model of intrauterine adhesion

Background

Intrauterine adhesion (IUA) is a major cause of female secondary infertility. We previously demonstrated that menstrual blood-derived stromal cell (MenSC) transplantation helped severe IUA patients have pregnancy and endometrium regeneration. We also initiated platelet-rich plasma (PRP) acted as a beneficial supplement in MenSC culturing and a potential endometrial receptivity regulator. Here, we investigated the therapeutic effect of combined transplantation of MenSCs with PRP in rat IUA models and the mechanisms of MenSCs in endometrium regeneration.

Methods

Rat IUA models were established by intrauterine mechanical injured. Nine days later, all rats were randomly assigned to four groups received different treatment: placebo, MenSC transplantation, PRP transplantation, and MenSCs + PRP transplantation. The traces of MenSCs were tracked with GFP label. Endometrial morphology and pathology, tissue proliferation, inflammation, pregnancy outcomes, and mechanism of MenSCs in the regeneration of endometrium were investigated.

Results

Notably, at days 9 and 18 post-treatment, MenSC transplantation significantly improved endometrial proliferation, angiogenesis, and morphology recovery and decreased collagen fibrosis and inflammation in the uterus. MenSCs had lesion chemotaxis, colonized around the endometrial glands. Gene expression of human-derived secretory protein IGF-1, SDF-1, and TSP-1 was detected in the uterus received MenSCs at day 18. The three treatments can all improve fertility in IUA rats. Moreover, gene expressions of cell proliferation, developmental processes, and other biological processes were induced in MenSC transplantation group. Hippo signaling pathway was the most significantly changed pathway, and the downstream factors CTGF, Wnt5a, and Gdf5 were significantly regulated in treatment groups. PRP enhanced these parameters through a synergistic effect.

Conclusions

In summary, MenSCs could effectively improve uterine proliferation, markedly accelerate endometrial damage repairment and promote fertility restoration in IUA rats, suggesting a paracrine restorative effect and Hippo signaling pathway stimulation. Our results indicate MenSCs, a valuable source of cells for transplantation in the treatment intrauterine adhesion. Combined with PRP, this cell therapy was more effective.

Electronic supplementary material

The online version of this article (10.1186/s13287-019-1155-7) contains supplementary material, which is available to authorized users.

Effect of Autologous Platelet-Rich Plasma Treatment on Refractory Thin Endometrium During the Frozen Embryo Transfer Cycle: A Pilot Study

Objective: Thin or damaged endometrium remains to be an unsolved problem in the treatment of patients with infertility. The empirical preference for endometrial thickness (EMT) among clinicians is >7 mm, and the refractory thin endometrium, which doesn't respond to standard medical therapies, can be the etiology of recurrent implantation failure (RIF). Autologous platelet-rich plasma (PRP) is known to help tissue regeneration and is widely used in various fields. In the present study, we conducted PRP treatment and investigated its effect on the refractory thin endometrium. Design: Prospective interventional study (https://cris.nih.go.kr/cris, clinical trial registration number: KCT0003375). Methods: Women who had a history of two or more failed IVF cycles and refractory thin endometrium were enrolled in this study. The main inclusion criteria were EMT of <7 mm after more than 2 cycles of previous medical therapy for increasing the EMT. Twenty-four women were enrolled in this study. The subjects were treated with intrauterine infusion of autologous PRP 2 or 3 times from menstrual cycle day 10 of their frozen-thawed embryo transfer (FET) cycle, and ET was performed 3 days after the final autologous PRP infusion. 22 patients underwent FET, and 2 patients were lost to follow up. Results: The ongoing pregnancy rate and LBR were both 20%. The implantation and clinical pregnancy rates were 12.7 and 30%, respectively, and the difference was statistically significant. The average increase in the EMT was 0.6 mm compared with the EMT of their previous cycle. However, this difference was not statistically significant. Further, EMT of 12 patients increased (mean difference: 1.3 mm), while that of seven patients decreased (mean difference: 0.7 mm); the EMT of one patient did not change. There were no adverse effects reported by the patients who were treated with autologous PRP. Conclusions: The use of autologous PRP improved the implantation, pregnancy, and live birth rates (LBR) of the patients with refractory thin endometrium. We assume that the ability of autologous PRP to restore the endometrial receptivity of damaged endometrium has some aspects other than increasing the EMT. The molecular basis of the treatment needs to be revealed in future studies.

Platelets enhance the ability of bone-marrow mesenchymal stem cells to promote cancer metastasis

Background

Bone marrow-derived mesenchymal stem cells (BM-MSCs) have been identified to be closely associated with cancer progression. Our previous experimental results showed that BM-MSCs promote tumor growth and metastasis of gastric cancer through paracrine-soluble cytokines or exosomes. However, the elements that affect the role of BM-MSCs in promoting tumor metastasis are not clear. It is known that thrombocytosis in cancer patients is very common. Recently, platelets are recognized to play a critical role in tumor progression.

Purpose

This study aims to observe the effect of BM-MSCs which were co-cultured with platelets on tumor cell metastasis.

Methods

Platelet aggregation rate and the expression of P-selectin of platelets co-incubated with conditioned medium of SGC-7901 cells and BM-MSCs were detected by flow cytometry and platelet aggregometer. We also analyzed the change of BM-MSCs after co-incubation with platelets or platelets which were treated with SGC-7901 cells using transwell assay and Western blot analysis. The proliferation and migration ability and expression of VEGF, c-Myc, and sall-4 in SGC-7901 cells treated with medium of BM-MSCs which were co-cultured with platelets were detected. SGC-7901 cells were injected into Balb/c nude mice and the extent of lung metastasis was observed. Both in vitro and in vivo assays were used to analyze the effect of platelets on enhancing the ability of BM-MSCs to promote cancer metastasis.

Results

Results suggested that BM-MSCs and tumor cells can promote platelet aggregation rate and the expression of P-selectin. The protein levels of α-smooth muscle actin, vimentin, and fibroblast activation protein in BM-MSCs were higher after co-incubation with platelets, and SB431542 was used to confirm the effect of TGF-β on transdifferentiation of BM-MSCs into cancer-associated fibroblasts. Medium of BM-MSCs treated with platelets enhanced the proliferation and migration ability of SGC-7901 cells. More lung metastases were found in mice which were injected with SGC-7901 cells treated with conditioned medium from BM-MSCs co-incubated with platelets.

Conclusion

Tumor cells and BM-MSCs activate platelets which can change the characteristics of BM-MSCs through secretion of TGF-β. Moreover, we found that platelets enhanced the effect of BM-MSCs on tumor metastasis, which suggested a potential target and approach for gastric cancer therapy.

Human menstrual blood: a renewable and sustainable source of stem cells for regenerative medicine

Stem cells (SCs) play an important role in autologous and even allogenic applications. Menstrual blood discharge has been identified as a valuable source of SCs which are referred to as menstrual blood-derived stem cells (MenSCs). Compared to SCs from bone marrow and adipose tissues, MenSCs come from body discharge and obtaining them is non-invasive to the body, they are easy to collect, and there are no ethical concerns. There is, hence, a growing interest in the functions of MenSCs and their potential applications in regenerative medicine. This review presents recent progress in research into MenSCs and their potential application. Clinical indications of using MenSCs for various regenerative medicine applications are emphasized, and future research is recommended to accelerate clinical applications of MenSCs.