Immunomodulatory effects and clinical application of exosomes derived from mesenchymal stem cells

Exosomes (Exos) are extracellular vesicles secreted by cells and serve as crucial mediators of intercellular communication. They play a pivotal role in the pathogenesis and progression of various diseases and offer promising avenues for therapeutic interventions. Exos derived from mesenchymal stem cells (MSCs) have significant immunomodulatory properties. They effectively regulate immune responses by modulating both innate and adaptive immunity. These Exos can inhibit excessive inflammatory responses and promote tissue repair. Moreover, they participate in antigen presentation, which is essential for activating immune responses. The cargo of these Exos, including ligands, proteins, and microRNAs, can suppress T cell activity or enhance the population of immunosuppressive cells to dampen the immune response. By inhibiting lymphocyte proliferation, acting on macrophages, and increasing the population of regulatory T cells, these Exos contribute to maintaining immune and metabolic homeostasis. Furthermore, they can activate immune-related signaling pathways or serve as vehicles to deliver microRNAs and other bioactive substances to target tumor cells, which holds potential for immunotherapy applications. Given the immense therapeutic potential of MSC-derived Exos, this review comprehensively explores their mechanisms of immune regulation and therapeutic applications in areas such as infection control, tumor suppression, and autoimmune disease management. This article aims to provide valuable insights into the mechanisms behind the actions of MSC-derived Exos, offering theoretical references for their future clinical utilization as cell-free drug preparations.

Mesenchymal stem cell exosomes enhance the development of hair follicle to ameliorate androgenetic alopecia

BACKGROUND

Mesenchymal stem cells (MSCs) and their secretome have significant potential in promoting hair follicle development. However, the effects of MSC therapy have been reported to vary due to their heterogeneous characteristics. Different sources of MSCs or culture systems may cause heterogeneity of exosomes.

AIM

To define the potential of human adipose-derived MSC exosomes (hADSC-Exos) and human umbilical cord-derived MSC exosomes (hUCMSC-Exos) for improving dermal papillary cell proliferation in androgenetic alopecia.

METHODS

We conducted liquid chromatography-mass spectrometry proteomic analysis of hADSC-Exos and hUCMSC-Exos. Liquid chromatography-mass spectrometry suggested that hADSC-Exos were related to metabolism and immunity. Additionally, the hADSC-Exo proteins regulated the cell cycle and other 9 functional groups.

RESULTS

We verified that hADSC-Exos inhibited glycogen synthase kinase-3β expression by activating the Wnt/β-catenin signaling pathway via cell division cycle protein 42, and enhanced dermal papillary cell proliferation and migration. Excess dihydrotestosterone caused androgenetic alopecia by shortening the hair follicle growth phase, but hADSC-Exos reversed these effects.

CONCLUSION

This study indicated that hair development is influenced by hADSC-Exo-mediated cell-to-cell communication via the Wnt/β-catenin pathway.

Fat mass and obesity-associated protein in mesenchymal stem cells inhibits osteoclastogenesis via lnc NORAD/miR-4284 axis in ankylosing spondylitis

BACKGROUND

Ankylosing spondylitis (AS) is recognized as a long-term inflammatory disorder that leads to inflammation in the spine and joints, alongside abnormal bone growth. In previous studies, we reported that mesenchymal stem cells (MSCs) derived from individuals with AS demonstrated a remarkable inhibition in the formation of osteoclasts compared to those obtained from healthy donors. The mechanism through which MSCs from AS patients achieve this inhibition remains unclear.

AIM

To investigate the potential underlying mechanism by which MSCs from individuals with ankylosing spondylitis (AS-MSCs) inhibit osteoclastogenesis.

METHODS

We analysed fat mass and obesity-associated (FTO) protein levels in AS-MSCs and MSCs from healthy donors and investigated the effects and mechanism by which FTO in MSCs inhibits osteoclastogenesis by coculturing and measuring the levels of tartrate-resistant acid phosphatase, nuclear factor of activated T cells 1 and cathepsin K.

RESULTS

We found that FTO, an enzyme responsible for removing methyl groups from RNA, was more abundantly expressed in MSCs from AS patients than in those from healthy donors. Reducing FTO levels was shown to diminish the capacity of MSCs to inhibit osteoclast development. Further experimental results revealed that FTO affects the stability of the long non-coding RNA activated by DNA damage (NORAD) by altering its N6-methyladenosine methylation status. Deactivating NORAD in MSCs significantly increased osteoclast formation by affecting miR-4284, which could regulate the MSC-mediated inhibition of osteoclastogenesis reported in our previous research.

CONCLUSION

This study revealed elevated FTO levels in AS-MSCs and found that FTO regulated the ability of AS-MSCs to inhibit osteoclast formation through the long noncoding RNA NORAD/miR-4284 axis.

Clinical experience with cryopreserved mesenchymal stem cells for cardiovascular applications: A systematic review

BACKGROUND

As living biodrugs, mesenchymal stem cells (MSCs) have progressed to phase 3 clinical trials for cardiovascular applications. However, their limited immediate availability hampers their routine clinical use.

AIM

To validate our hypothesis that cryopreserved MSCs (CryoMSCs) are as safe and effective as freshly cultured MSC counterparts but carry logistical advantages.

METHODS

Four databases were systematically reviewed for relevant randomized controlled trials (RCTs) evaluating the safety and efficacy of CryoMSCs from various tissue sources in treating patients with heart disease. A subgroup analysis was performed based on MSC source and post-thaw cell viability to determine treatment effects across different CryoMSCs sources and viability status. Weighted mean differences (WMDs) and odds ratios were calculated to measure changes in the estimated treatment effects. All statistical analyses were performed using RevMan version 5.4.1 software.

RESULTS

Seven RCTs (285 patients) met the eligibility criteria for inclusion in the meta-analysis. During short-term follow-up, CryoMSCs demonstrated a significant 2.11% improvement in left ventricular ejection fraction (LVEF) [WMD (95%CI) = 2.11 (0.66-3.56), P = 0.004, I 2 = 1%], with umbilical cord-derived MSCs being the most effective cell type. However, the significant effect on LVEF was not sustained over the 12 months of follow-up. Subgroup analysis demonstrated a substantial 3.44% improvement in LVEF [WMD (95%CI) = 3.44 (1.46-5.43), P = 0.0007, I 2 = 0%] when using MSCs with post-thaw viability exceeding 80%. There was no statistically significant difference in the frequency of major cardiac adverse events observed in rehospitalization or mortality in patients treated with CryoMSCs vs the control group.

CONCLUSION

CryoMSCs are a promising option for heart failure patients, particularly considering the current treatment options for cardiovascular diseases. Our data suggest that CryoMSCs could be a viable alternative or complementary treatment to the current options, potentially improving patient outcomes.

Regulation of lncRNA-ENST on Myc-mediated mitochondrial apoptosis in mesenchymal stem cells: In vitro evidence implicated for acute lung injury therapeutic potential

BACKGROUND

Acute lung injury (ALI) is a fatal and heterogeneous disease. While bone marrow mesenchymal stem cells (BMSCs) have shown promise in ALI repair, their efficacy is compromised by a high apoptotic percentage. Preliminary findings have indicated that long noncoding RNA (lncRNA)-ENST expression is markedly downregulated in MSCs under ischemic and hypoxic conditions, establishing a rationale for in vitro exploration.

AIM

To elucidate the role of lncRNA-ENST00000517482 (lncRNA-ENST) in modulating MSC apoptosis.

METHODS

Founded on ALI in BEAS-2B cells with lipopolysaccharide, this study employed a transwell co-culture system to study BMSC tropism. BMSCs were genetically modified to overexpress or knockdown lncRNA-ENST. After analyzing the effects on autophagy, apoptosis and cell viability, the lncRNA-ENST/miR-539/c-MYC interaction was confirmed by dual-luciferase assays.

RESULTS

These findings have revealed a strong correlation between lncRNA-ENST levels and the apoptotic and autophagic status of BMSCs. On the one hand, the over-expression of lncRNA-ENST, as determined by Cell Counting Kit-8 assays, increased the expression of autophagy markers LC3B, ATG7, and ATG5. On the other hand, it reduced apoptosis and boosted BMSC viability. In co-cultures with BEAS-2B cells, lncRNA-ENST overexpression also improved cell vitality. Additionally, by downregulating miR-539 and upregulating c-MYC, lncRNA-ENST was found to influence mitochondrial membrane potential, enhance BMSC autophagy, mitigate apoptosis and lower the secretion of pro-inflammatory cytokines interleukin-6 and interleukin-1β. Collectively, within the in vitro framework, these results have highlighted the therapeutic potential of BMSCs in ALI and the pivotal regulatory role of lncRNA-ENST in miR-539 and apoptosis in lipopolysaccharide-stimulated BEAS-2B cells.

CONCLUSION

Our in vitro results show that enhanced lncRNA ENST expression can promote BMSC proliferation and viability by modulating the miR-539/c-MYC axis, reduce apoptosis and induce autophagy, which has suggested its therapeutic potential in the treatment of ALI.

DNA methyltransferase 1/miR-342-3p/Forkhead box M1 signaling axis promotes self-renewal in cervical cancer stem-like cells in vitro and nude mice models

BACKGROUND

Cervical cancer (CC) stem cell-like cells (CCSLCs), defined by the capacity of differentiation and self-renewal and proliferation, play a significant role in the progression of CC. However, the molecular mechanisms regulating their self-renewal are poorly understood. Therefore, elucidation of the epigenetic mechanisms that drive cancer stem cell self-renewal will enhance our ability to improve the effectiveness of targeted therapies for cancer stem cells.

AIM

To explore how DNA methyltransferase 1 (DNMT1)/miR-342-3p/Forkhead box M1 (FoxM1), which have been shown to have abnormal expression in CCSLCs, and their signaling pathways could stimulate self-renewal-related stemness in CCSLCs.

METHODS

Sphere-forming cells derived from CC cell lines HeLa, SiHa and CaSki served as CCSLCs. Self-renewal-related stemness was identified by determining sphere and colony formation efficiency, CD133 and CD49f protein level, and SRY-box transcription factor 2 and octamer-binding transcription factor 4 mRNA level. The microRNA expression profiles between HeLa cells and HeLa-derived CCSLCs or mRNA expression profiles that HeLa-derived CCSLCs were transfected with or without miR-342-3p mimic were compared using quantitative PCR analysis. The expression levels of DNMT1 mRNA, miR-342-3p, and FoxM1 protein were examined by quantitative real-time PCR and western blotting. In vivo carcinogenicity was assessed using a mouse xenograft model. The functional effects of the DNMT1/miR-342-3p/FoxM1 axis were examined by in vivo and in vitro gain-of-activity and loss-of-activity assessments. Interplay among DNMT1, miR-342-3p, and FoxM1 was tested by methylation-specific PCR and a respective luciferase reporter assay.

RESULTS

CCSLCs derived from the established HeLa cell lines displayed higher self-renewal-related stemness, including enhanced sphere and colony formation efficiency, increased CD133 and CD49f protein level, and heightened transcriptional quantity of stemness-related factors SRY-box transcription factor 2 and octamer-binding transcription factor 4 in vitro as well as a stronger tumorigenic potential in vivo compared to their parental cells. Moreover, quantitative PCR showed that the miR-342-3p level was downregulated in HeLa-derived CCSLCs compared to HeLa cells. Its mimic significantly decreased DNMT1 and FoxM1 mRNA expression levels in CCSLCs. Knockdown of DNMT1 or miR-342-3p mimic transfection suppressed DNMT1 expression, increased miR-342-3p quantity by promoter demethylation, and inhibited CCSLC self-renewal. Inhibition of FoxM1 by shRNA transfection also resulted in the attenuation of CCSLC self-renewal but had little effect on the DNMT1 activity and miR-342-3p expression. Furthermore, the loss of CCSLC self-renewal exerted by miR-342-3p mimic was inverted by the overexpression of DNMT1 or FoxM1. Furthermore, DNMT1 and FoxM1 were recognized as straight targets by miR-342-3p in HeLa-derived CCSLCs.

CONCLUSION

Our findings suggested that a novel DNMT1/miR-342-3p/FoxM1 signal axis promotes CCSLC self-renewal and presented a potential target for the treatment of CC through suppression of CCSLC self-renewal. However, this pathway has been previously implicated in CC, as evidenced by prior studies showing miR-342-3p-mediated downregulation of FoxM1 in cervical cancer cells. Additionally, research on liver cancer further supports the involvement of miR-342-3p in suppressing FoxM1 expression. While our study contributed to this body of knowledge, we did not present a completely novel axis but reinforced the therapeutic potential of targeting the DNMT1/miR-342-3p/FoxM1 axis to suppress CCSLC self-renewal in CC treatment.

MiR-21-5p-enriched exosomes from hiPSC-derived cardiomyocytes exhibit superior cardiac repair efficacy compared to hiPSC-derived exosomes in a murine MI model

BACKGROUND

Heart disease remains a leading cause of mortality worldwide, with existing treatments often failing to effectively restore damaged myocardium. Human-induced pluripotent stem cells (hiPSCs) and their derivatives offer promising therapeutic options; however, challenges such as low retention, engraftment issues, and tumorigenic risks hinder their clinical utility. Recent focus has shifted to exosomes (exos) - nanoscale vesicles that facilitate intercellular communication - as a safer and more versatile alternative. Understanding the specific mechanisms and comparative efficacy of exos from hiPSCs vs hiPSC-derived cardiomyocytes (hiPSC-CMs) is crucial for advancing cardiac repair therapies.

AIM

To evaluate and compare the therapeutic efficacy of exos secreted by hiPSCs and hiPSC-CMs in cardiac repair, and to elucidate the role of microRNA 21-5p (miR-21-5p) in the observed effects.

METHODS

We differentiated hiPSCs into CMs using small molecule methods and characterized the cells and their exos.

RESULTS

Our findings indicate that hiPSC-CMs and their exos enhanced cardiac function, reduced infarct size, and decreased myocardial fibrosis in a murine myocardial infarction model. Notably, hiPSC-CM exos outperformed hiPSC-CM cell therapy, showing improved ejection fraction and reduced apoptosis. We identified miR-21-5p, a microRNA in hiPSC-CM exos, as crucial for CM survival. Exos with miR-21-5p were absorbed by AC16 cells, suggesting a mechanism for their cytoprotective effects.

CONCLUSION

Overall, hiPSC-CM exos could serve as a potent therapeutic agent for myocardial repair, laying the groundwork for future research into exos as a treatment for ischemic heart disease.

Emerging role of mesenchymal stem cell-derived exosomes in the repair of acute kidney injury

Acute kidney injury (AKI) is a clinical syndrome characterized by a rapid deterioration in kidney function and has a significant impact on patient health and survival. Mesenchymal stem cells (MSCs) have the potential to enhance renal function by suppressing the expression of cell cycle inhibitors and reducing the expression of senescence markers and microRNAs via paracrine and endocrine mechanisms. MSC-derived exosomes can alleviate AKI symptoms by regulating DNA damage, apoptosis, and other related signaling pathways through the delivery of proteins, microRNAs, long-chain noncoding RNAs, and circular RNAs. This technique is both safe and effective. MSC-derived exosomes may have great application prospects in the treatment of AKI. Understanding the underlying mechanisms will foster the development of new and promising therapeutic strategies against AKI. This review focused on recent advancements in the role of MSCs in AKI repair as well as the mechanisms underlying the role of MSCs and their secreted exosomes. It is anticipated that novel and profound insights into the functionality of MSCs and their derived exosomes will emerge.

Cyclodextrin host-guest complex to facilitate sinomenine-based osteoporosis therapy

Xiao et al reported on the natural product sinomenine (SIN), which is a traditional Chinese medicine for treating osteoporosis via its modulation of autophagy; however, SIN was dissolved in dimethyl sulfoxide prior to administration, which is not conducive to the development of clinical injectables. By comparing solubilization techniques, including amorphisation, emulsification, micellisation, nano-crystallisation and host-guest inclusion, we found that the solubilization of SIN by host-guest inclusion can enhance solubility and improve stability and has an increased release rate and enhanced bioavailability. Therefore, we conclude that host-guest inclusion holds promise for SIN solubilization. To solubilise SIN, we selected β-cyclodextrin as the host agent considering its excellent biocompatibility, efficient encapsulation ability, mature preparation process and adequate drug stability. If the prerequisites of SIN-β-cyclodextrin complexes in terms of safety, efficacy, stability and the relevant laws and regulations are met, its clinical application for the treatment of osteoporosis may be achieved.

Efficacy equivalence but hidden hurdles: Can serum-free human umbilical cord mesenchymal stem cells translate to clinically superior osteoarthritis therapy

This article discusses the study by Xiao et al, which investigated the therapeutic efficacy of serum-free cultured human umbilical cord mesenchymal stem cells (N-hUCMSCs) in a mouse model of knee osteoarthritis. The results showed that N-hUCMSCs alleviated osteoarthritis-related cartilage damage and inflammation comparably to both serum-cultured hUCMSCs and hyaluronic acid. While these findings broaden the potential clinical utility of N-hUCMSCs by circumventing certain drawbacks of serum-based cultures, the equivalence in efficacy raises important questions. First, how do N-hUCMSCs differ phenotypically from serum-cultured hUCMSCs, particularly in terms of proliferation rate, replicative capacity, and senescence profile? Second, what advantages might N-hUCMSCs offer over hyaluronic acid - a well-established therapy - beyond avoiding xenogeneic components and ethical concerns? Future research should focus on long-term phenotypic stability, sustained functional benefits, safety profiles, and mechanistic insights to ascertain whether N-hUCMSCs can surpass current standards of care.

Perspectives on Schwann-like cells derived from bone marrow-mesenchymal stem cells: Advancing peripheral nerve injury therapies

Peripheral nerve injuries are clinical conditions that often result in functional deficits, compromising patient quality of life. Given the relevance of these injuries, new treatment strategies are constantly being investigated. Although mesenchymal stem cells already demonstrate therapeutic potential due to their paracrine action, the transdifferentiation of these cells into Schwann-like cells (SLCs) represents a significant advancement in nerve injury therapy. Recent studies indicate that SLCs can mimic the functions of Schwann cells, with promising results in animal models. However, challenges remain, such as the diversity of transdifferentiation protocols and the scalability of these therapies for clinical applications. A recent study by Zou et al provided a comprehensive overview of the role of bone marrow-derived mesenchymal stem cells in the treatment of peripheral nerve injuries. Therefore, we would like to discuss and explore the use of SLCs derived from bone marrow-derived mesenchymal stem cells in more detail as a promising alternative in the field of nerve regeneration.

Effect of tandem autologous stem cell transplantation on survival in pediatric patients with high-risk solid tumors in South China

BACKGROUND

Despite advances in treatment, the prognosis for patients with high-risk pediatric solid tumors remains dismal. Tandem autologous stem cell transplantation (ASCT) offers promise for improving outcomes in these patients. This study aimed to examine the efficacy and prognostic factors of tandem ASCT in pediatric patients with high-risk solid tumors.

AIM

To determine the survival outcomes and prognostic factors in pediatric patients with high-risk solid tumors undergoing tandem ASCT.

METHODS

A total of 40 pediatric patients with high-risk solid tumors treated from March 2015 to August 2022 were included in this retrospective study. The diagnoses of the patients included neuroblastoma, germ cell tumors, atypical teratoid/rhabdoid tumor, medulloblastoma, and pineoblastoma. After induction chemotherapy, all patients received tandem ASCT and were allocated into two groups (group A and group B) based on high-dose chemotherapy regimens. Prognostic relevance was evaluated by examining patient characteristics, such as sex, age, lactate dehydrogenase levels, primary site, the number of metastatic sites, and bone marrow involvement.

RESULTS

The median follow-up duration since the first ASCT was 24 months (range: 1-91 months), with 5-year overall survival (OS) and event-free survival (EFS) rates of 73% and 70%, respectively, for the entire cohort. The 3-year OS rates were 67% for group A and 87% for group B (P = 0.29), with corresponding 3-year EFS rates of 67% and 79% (P = 0.57). Among neuroblastoma patients, the 5-year OS and EFS were 69% and 63% (P = 0.23). Univariable analysis revealed a notable association of age ≥ 36 months and elevated lactate dehydrogenase level at diagnosis with poorer OS. Despite acute adverse effects, all patients demonstrated good tolerance to the treatment, with no occurrences of transplant-related mortality.

CONCLUSION

Tandem ASCT demonstrates promising survival outcomes for patients with high-risk solid tumors, particularly neuroblastoma, with manageable toxicity and no transplant-related mortality.

Effects of macrophages on the osteogenic differentiation of adipose tissue-derived stem cells in two-dimensional and three-dimensional cocultures

BACKGROUND

Fracture is one of the most pervasive injuries in the musculoskeletal system, and there is a complex interaction between macrophages and adipose tissue-derived stem cells (ADSCs) in fracture healing. However, two-dimensional (2D) coculture of macrophages and ADSCs can not accurately mimic the in vivo cell microenvironment.

AIM

To establish both 2D and 3D osteogenic coculture models to investigate the interaction between macrophages and ADSCs.

METHODS

After obtaining ADSCs from surgery and inducing differentiation of the THP1 cell line, we established 2D and 3D osteogenic coculture models. To assess the level of osteogenic differentiation, we used alizarin red staining and measured the relative expression levels of osteogenic differentiation markers osteocalcin, Runt-related transcription factor 2, and alkaline phosphatase through polymerase chain reaction. Verification was conducted by analyzing the expression changes of N-cadherin and the activation of the Wnt/β-catenin signaling pathway using western blotting.

RESULTS

In this study, it was discovered that macrophages in 3D culture inhibited osteogenic differentiation of ADSCs, contrary to the effect in 2D culture. This observation confirmed the significance of intricate intercellular connections in the 3D culture environment. Additionally, the 3D culture group exhibited significantly higher N-cadherin expression and showed reduced β-catenin and Wnt1 protein levels compared to the 2D culture group.

CONCLUSION

Macrophages promoted ADSC osteogenic differentiation in 2D culture conditions but inhibited it in 3D culture. The 3D culture environment might inhibit the Wnt/β-catenin signaling pathway by upregulating N-cadherin expression, ultimately hindering the osteogenic differentiation of ADSCs. By investigating the process of osteogenesis in ADSCs, this study provides novel ideas for exploring 3D osteogenesis in ADSCs, fracture repair, and other bone trauma repair.

Effect of adipose-derived stem cells exosomes cross-linked chitosan-αβ-glycerophosphate thermosensitive hydrogel on deep burn wounds

BACKGROUND

Burn wound management is challenging, and while mesenchymal stem cell-derived exosomes show therapeutic potential, optimal delivery methods are unclear.

AIM

To study chitosan (CS)-αβ-glycerophosphate (CS-αβ-GP) hydrogel crosslinked with adipose-derived stem cell exosomes (ASC-Exos) for healing deep burn injuries.

METHODS

Rats with deep burn injuries were divided into the CS + ASCs-Exos group, the ASCs-Exos group, the CS group, and the control group. The healing rates on days 4, 7, and 14 after treatment were analyzed using ImageJ software. On day 14, the tissues were stained with hematoxylin and eosin staining, Masson’s trichrome staining, and immunohistochemical analysis to evaluate tumor necrosis factor α, interleukin-6 (IL-6), IL-1α, IL-10, transforming growth factor β, and epidermal growth factor. The mRNA levels of IL-1α, CD86, C-C motif chemokine ligand 22, and CD163 were evaluated through quantitative polymerase chain reaction.

RESULTS

The CS + ASC-Exos group exhibited enhanced healing, reduced lymphocyte infiltration, blood vessels, and muscle fiber distribution. Increased IL-10, transforming growth factor β, and epidermal growth factor and decreased tumor necrosis factor α, IL-1α, and IL-6 expression were observed. Quantitative polymerase chain reaction revealed reduced IL-1α and CD86 and increased C-C motif chemokine ligand 22 and CD163 expression. Protein analysis showed downregulation of phosphorylated inhibitor of kappa Balpha and P65 in the nuclear factor κB (NF-κB) pathway. ASC-Exos crosslinked with CS-αβ-GP hydrogel demonstrates superior effects in anti-inflammation, wound healing promotion, and promotion of M1 macrophage transformation to M2 macrophage by blocking the NF-κB pathway compared to ASC-Exos alone.

CONCLUSION

Our research demonstrates that the ASC-Exos cross-linked CS-αβ-GP hydrogel represents an advanced therapeutic approach for treating deep burn wounds. It has anti-inflammatory effects, promotes wound healing, and facilitates the transition of M1 macrophages to M2 macrophages by blocking the NF-κB pathway.

Fetal mice dermal mesenchymal stem cells promote wound healing by inducing M2 type macrophage polarization

BACKGROUND

Mesenchymal stem cells, found in various tissues, possess significant healing and immunomodulatory properties, influencing macrophage polarization, which is essential for wound repair. However, chronic wounds present significant therapeutic challenges, requiring novel strategies to improve healing outcomes.

AIM

To investigate the potential of fetal dermal mesenchymal stem cells (FDMSCs) in enhancing wound healing through modulation of macrophage polarization, specifically by promoting the M2 phenotype to address inflammatory responses in chronic wounds.

METHODS

FDMSCs were isolated from BalB/C mice and co-cultured with RAW264.7 macrophages to assess their effects on macrophage polarization. Flow cytometry, quantitative reverse transcriptase polymerase chain reaction, and histological analyses were employed to evaluate shifts in macrophage phenotype and wound healing in a mouse model. Statistical analysis was performed using GraphPad Prism.

RESULTS

FDMSCs induced macrophage polarization from the M1 to M2 phenotype, as demonstrated by a reduction in pro-inflammatory markers (inducible nitric oxide synthase, interleukin-6) and an increase in anti-inflammatory markers [mannose receptor (CD206), arginase-1] in co-cultured RAW264.7 macrophages. These shifts were confirmed by flow cytometry. In an acute skin wound model, FDMSC-treated mice exhibited faster wound healing, enhanced collagen deposition, and improved vascular regeneration compared to controls. Significantly higher expression of arginase-1 further indicated an enriched M2 macrophage environment.

CONCLUSION

FDMSCs effectively modulate macrophage polarization from M1 to M2, reduce inflammation, and enhance tissue repair, demonstrating their potential as an immunomodulatory strategy in wound healing. These findings highlight the promising therapeutic application of FDMSCs in managing chronic wounds.

Asthma and stem cell therapy

The global incidence of asthma, a leading respiratory disorder affecting more than 235 million people, has dramatically increased in recent years. Characterized by chronic airway inflammation and an imbalanced response to airborne irritants, this chronic condition is associated with elevated levels of inflammatory factors and symptoms such as dyspnea, cough, wheezing, and chest tightness. Conventional asthma therapies, such as corticosteroids, long-acting β-agonists, and anti-inflammatory agents, often evoke diverse adverse reactions and fail to reduce symptoms and hospitalization rates over the long term effectively. These limitations have prompted researchers to explore innovative therapeutic strategies, including stem cell-related interventions, offering hope to those afflicted with this incurable disease. In this review, we describe the characteristics of stem cells and critically assess the potential and challenges of stem cell-based therapies to improve disease management and treatment outcomes for asthma and other diseases.

Nicotinamide adenine dinucleotide rejuvenates septic bone marrow mesenchymal stem cells

BACKGROUND

Sepsis is a severe illness characterized by systemic and multiorgan reactive responses and damage. However, the impact of sepsis on the bone marrow, particularly on bone marrow mesenchymal stem cells (BMSCs), is less reported. BMSCs are critical stromal cells in the bone marrow microenvironment that maintain bone stability and hematopoietic homeostasis; however, the impairment caused by sepsis remains unknown.

AIM

To investigate the effects of sepsis on BMSCs and the underlying mechanisms.

METHODS

BMSCs were obtained from healthy donors and patients with sepsis. We compared the self-renewal capacity, differentiation potential, and hematopoietic supportive ability in vitro. Senescence of septic BMSCs was assessed using β-galactosidase staining, senescence-associated secretory phenotype, intracellular reactive oxygen species levels, and the expression of P16 and P21. Finally, the changes in septic BMSCs after nicotinamide adenine dinucleotide (NAD) treatment were evaluated.

RESULTS

Septic BMSCs showed decreased proliferation and self-renewal, bias towards adipogenic differentiation, and weakened osteogenic differentiation. Additionally, hematopoietic supportive capacity declines in sepsis. The levels of aging markers were significantly higher in the septic BMSCs. After NAD treatment, the proliferation capacity of septic BMSCs showed a recovery trend, with increased osteogenic and hematopoietic supportive capacities. Sepsis resulted in decreased expression of sirtuin 3 (SIRT3) in BMSCs, whereas NAD treatment restored SIRT3 expression, enhanced superoxide dismutase enzyme activity, reduced intracellular reactive oxygen species levels, maintained mitochondrial stability and function, and ultimately rejuvenated septic BMSCs.

CONCLUSION

Sepsis accelerates the aging of BMSCs, as evidenced by a decline in self-renewal and osteogenic capabilities, as well as weakened hematopoietic support functions. These deficiencies can be effectively reversed via the NAD/SIRT3/superoxide dismutase pathway.

Stem cell therapy: A promising therapeutic approach for skeletal muscle atrophy

Skeletal muscle atrophy results from disruptions in the growth and metabolism of striated muscle, leading to a reduction or loss of muscle fibers. This condition not only significantly impacts patients’ quality of life but also imposes substantial socioeconomic burdens. The complex molecular mechanisms driving skeletal muscle atrophy contribute to the absence of effective treatment options. Recent advances in stem cell therapy have positioned it as a promising approach for addressing this condition. This article reviews the molecular mechanisms of muscle atrophy and outlines current therapeutic strategies, focusing on mesenchymal stem cells, induced pluripotent stem cells, and their derivatives. Additionally, the challenges these stem cells face in clinical applications are discussed. A deeper understanding of the regenerative potential of various stem cells could pave the way for breakthroughs in the prevention and treatment of muscle atrophy.

Exosomal miR-203 from bone marrow stem cells targets the SOCS3/NF-κB pathway to regulate neuroinflammation in temporal lobe epilepsy

BACKGROUND

Epilepsy is a prevalent chronic neurological disorder affecting 50 million individuals globally, with temporal lobe epilepsy (TLE) being the most common form. Despite advances in antiepileptic drug development, over 30% of patients suffer from drug-resistant epilepsy, which can lead to severe cognitive impairments and adverse psychosocial outcomes.

AIM

To explore the role of bone marrow mesenchymal stem cell (BMSC)-derived exosomal miR-203 in the regulation of neuroinflammation in a mouse model of epilepsy, providing a theoretical basis for the development of targeted microRNA delivery therapies for drug-resistant epilepsy.

METHODS

Adult male C57BL/6 mice were divided into a control group and a TLE model of 30 mice each, and the TLE model group was established by injecting kainic acid. BMSCs were isolated from the mice, and exosomes were purified using ultracentrifugation. Exosomal miR-203 was identified and characterized using high-throughput sequencing and quantitative reverse-transcription polymerase chain reaction. The uptake of exosomes by hippocampal neurons and the subsequent effects on neuroinflammatory markers were assessed using in vitro cell culture models.

RESULTS

Exosomal miR-203 exhibited a significant upregulation in BMSCs derived from epileptic mice. In vitro investigations demonstrated the efficient internalization of these exosomes by hippocampal neurons, resulting in downregulation of suppressor of cytokine signaling 3 expression and activation of the nuclear factor kappaB pathway, ultimately leading to enhanced secretion of pro-inflammatory cytokines.

CONCLUSION

Our study identifies exosomal miR-203 as a key regulator of neuroinflammation in a mouse model of epilepsy. The findings suggest that targeting miR-203 may offer a novel therapeutic strategy for epilepsy by modulating the suppression of cytokine signaling 3/nuclear factor kappaB pathway, thus providing a potential avenue for the development of cell-free therapeutics.

WDR36 inhibits the osteogenic differentiation and migration of periodontal ligament stem cells

BACKGROUND

Periodontitis is an inflammatory disease caused by the host’s immune response and various interactions between pathogens, which lead to the loss of connective tissue and bone. In recent years, mesenchymal stem cell (SC) transplantation technology has become a research hotspot, which can form periodontal ligament, cementum, and alveolar bone through proliferation and differentiation.

AIM

To elucidate the regulatory effects of WD repeat-containing protein 36 (WDR36) on the senescence, migration, and osteogenic differentiation of periodontal ligament SCs (PDLSCs).

METHODS

The migration and chemotaxis of PDLSCs were detected by the scratch-wound migration test and transwell chemotaxis test. Alkaline phosphatase (ALP) activity, Alizarin red staining, calcium content, and real-time reverse transcription polymerase chain reaction (RT-qPCR) of key transcription factors were used to detect the osteogenic differentiation function of PDLSCs. Cell senescence was determined by senescence-associated β-galactosidase staining.

RESULTS

The 24-hour and 48-hour scratch-wound migration test and 48-hour transwell chemotaxis test showed that overexpression of WDR36 inhibited the migration/chemotaxis of PDLSCs. Simultaneously, WDR36 depletion promoted the migration/chemotaxis of PDLSCs. The results of ALP activity, Alizarin red staining, calcium content, and RT-qPCR showed that overexpression of WDR36 inhibited the osteogenic differentiation of PDLSCs, and WDR36 depletion promoted the osteogenic differentiation of PDLSCs. Senescence-associated β-galactosidase staining showed that 0.1 μg/mL icariin (ICA) and overexpression of WDR36 inhibited the senescence of PDLSCs, and WDR36 depletion promoted the osteogenic differentiation of PDLSCs.

CONCLUSION

WDR36 inhibits the migration and chemotaxis, osteogenic differentiation, and senescence of PDLSCs; 0.1 μg/mL ICA inhibits the senescence of PDLSCs. Therefore, WDR36 might serve as a target for periodontal tissue regeneration and the treatment of periodontitis.

Impact of miR-214-5p and miR-21-5p from hypoxic endometrial exosomes on human umbilical cord mesenchymal stem cell function. World J Stem Cells 2025;17:102404. [DOI: 10.4252/wjsc.v17.i2.102404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Exosomes derived from hypoxic endometrial epithelial cells are pivotal in cellular communication and tissue repair, offering new perspectives on reproductive health. This manuscript highlights the study by Zhang et al, which investigates the effects of miR-214-5p and miR-21-5p in hypoxic cell-derived exosomes on human umbilical cord mesenchymal stem cells. The study reveals that low levels of these microRNAs activate the signal transducer and activator of transcription 3 signaling pathway, enhancing human umbilical cord mesenchymal stem cell migration and differentiation. These findings provide novel insights into therapeutic strategies for improving endometrial health and addressing infertility linked to thin endometrium.

Induced pluripotent stem cell-derived mesenchymal stem cells for modeling and treating metabolic associated fatty liver disease and metabolic associated steatohepatitis: Challenges and opportunities

The potential of induced pluripotent stem cells (iPSCs) for modeling and treating metabolic associated fatty liver disease (MAFLD) and metabolic associated steatohepatitis (MASH) is emerging. MAFLD is a growing global health concern, currently with limited treatment options. While primary mesenchymal stem cells hold promise, iPSCs offer a versatile alternative due to their ability to differentiate into various cell types, including iPSC-derived mesenchymal stem cells. However, challenges remain, including optimizing differentiation protocols, ensuring cell safety, and addressing potential tumorigenicity risks. In addition, iPSCs offer the possibility to generate complex cellular models, including three-dimensional organoid models, which are closer representations of the human disease than animal models. Those models would also be valuable for drug discovery and personalized medicine approaches. Overall, iPSCs and their derivatives offer new perspectives for advancing MAFLD/MASH research and developing novel therapeutic strategies. Further research is needed to overcome current limitations and translate this potential into effective clinical applications.

Protective activity of adipose-derived stem cell extracellular vesicles in ischemia and/or reperfusion

Increasing evidence of the significant clinical value of protection against ischemia/reperfusion injury has contributed to the realization of the independent importance of this approach in improving prognosis and reducing cardiovascular mortality. Extracellular vesicles (EVs) derived by adipose mesenchymal stem cells may mediate the paracrine effects of stem cells and provide regenerative and anti-inflammatory properties, which are enhanced by γ-aminobutyric acid. The protective effects on cardiac myocytes may result from the EV embarked by miR-21-5p, which is a target for thioredoxin-interacting protein, regulating the formation of thioredoxin-interacting protein-thioredoxin complexes and subsequently enhancing the antioxidant activity of thioredoxin. It has been found that γ-aminobutyric acid governs myocardial bioenergetics through suppressing inflammation and supporting mitochondrial structure. Finally, stem cell-based cell-free therapy based on adipose-derived stem cell EVs is considered a promising approach to individualized management of ischemia-induced cardiomyopathy.

Immortalization of epidural fat-derived mesenchymal stem cells: In vitro characterization and adipocyte differentiation potential

BACKGROUND

Mesenchymal stem cells (MSCs) are promising candidates for regenerative therapy due to their self-renewal capability, multilineage differentiation potential, and immunomodulatory effects. The molecular characteristics of MSCs are influenced by their location. Recently, epidural fat (EF) and EF-derived MSCs (EF-MSCs) have garnered attention due to their potential benefits to the spinal microenvironment and their high expression of neural SC markers. However, their clinical applications are limited due to cell senescence and limited accessibility of EF. Although many studies have attempted to establish an immortalized, stable SC line, the characteristics of immortalized EF-MSCs remain to be clarified.

AIM

To establish and analyze stable immortalized EF-MSCs.

METHODS

The phenotypes of EF-MSCs were analyzed using optical microscopy. Cell immortalization was performed using lentiviral vectors. The biomolecular characteristics of the cells were analyzed by immunoblotting, quantitative PCR, and proteomics.

RESULTS

The immortalized EF-MSCs demonstrated a significantly extended lifespan compared to the control group, with well-preserved adipogenic potential and SC surface marker expression. Introduction of human telomerase reverse transcriptase genes markedly increased the lifespan of EF-MSCs. Proteomics analysis revealed substantial increase in the expression of DNA replication pathway components in immortalized EF-MSCs.

CONCLUSION

Immortalized EF-MSCs exhibited significantly enhanced proliferative capacity, retained adipogenic potential, and upregulated the expression of DNA replication pathway components.

Stromal vascular fraction: Mechanisms and application in reproductive disorders

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