Extracellular vesicles derived from "serum and glucose" deprived HUCMSCs promoted skin wound healing through enhanced angiogenesis.

Extracellular vesicles (EVs) produced from MSCs were currently considered as a novel therapeutic agent for skin tissue regeneration and repair. Preconditioning stem cells may activate more molecular pathways and release more bioactive agents. In this study, we obtained EVs from normal (N-EVs) and serum- and glucose-deprived (SGD-EVs) human umbilical cord mesenchymal stem cells (HUCMSCs), and showed that SGD-EVs promoted the migration, proliferation, and tube formation of HUVECs in vitro. In vivo experiments utilizing a rat model show that both N-EVs and SGD-EVs boosted angiogenesis of skin defects and accelerated skin wound healing, while treating wounds with SGD-EVs led to faster skin healing and enhanced angiogenesis. miRNA sequencing showed that miR-29a-3p was abundant in SGD-EVs, and overexpressing miR-29a-3p enhanced the angiogenic ability of HUVECs, while inhibiting miR-29a-3p presented the opposite effect. Further studies demonstrated that miR-29a-3p directly targeted CTNNBIP1, which mediated angiogenesis of HUCMSCs-derived EVs through inhibiting CTNNBIP1 to activate Wnt/ß-catenin signaling pathway. Taken together, these findings suggested that SGD-EVs promote angiogenesis via transferring miR-29a-3p, and activation of Wnt/ß-catenin signaling pathway played a crucial role in SGD-EVs-induced VEGFA production during wound angiogenesis. Our results offered a new avenue for modifying EVs to enhance tissue angiogenesis and augment its role in skin repair.

Research progress and prospects of benefit-risk assessment methods for umbilical cord mesenchymal stem cell transplantation in the clinical treatment of spinal cord injury.

Over the past decade, we have witnessed the development of cell transplantation as a new strategy for repairing spinal cord injury (SCI). However, due to the complexity of the central nervous system (CNS), achieving successful clinical translation remains a significant challenge. Human umbilical cord mesenchymal stem cells (hUMSCs) possess distinct advantages, such as easy collection, lack of ethical concerns, high self-renewal ability, multilineage differentiation potential, and immunomodulatory properties. hUMSCs are promising for regenerating the injured spinal cord to a significant extent. At the same time, for advancing SCI treatment, the appropriate benefit and risk evaluation methods play a pivotal role in determining the clinical applicability of treatment plans. Hence, this study discusses the advantages and risks of hUMSCs in SCI treatment across four dimensions-comprehensive evaluation of motor and sensory function, imaging, electrophysiology, and autonomic nervous system (ANS) function-aiming to improve the rationality of relevant clinical research and the feasibility of clinical translation.

Mesenchymal Stem Cells Alleviate Acute Liver Failure through Regulating Hepatocyte Apoptosis and Macrophage Polarization.

Background and Aims: Acute liver failure (ALF) is a life-threatening clinical problem with limited treatment options. Administration of human umbilical cord mesenchymal stem cells (hUC-MSCs) may be a promising approach for ALF. This study aimed to explore the role of hUC-MSCs in the treatment of ALF and the underlying mechanisms. Methods: A mouse model of ALF was induced by lipopolysaccharide and d-galactosamine administration. The therapeutic effects of hUC-MSCs were evaluated by assessing serum enzyme activity, histological appearance, and cell apoptosis in liver tissues. The apoptosis rate was analyzed in AML12 cells. The levels of inflammatory cytokines and the phenotype of RAW264.7 cells co-cultured with hUC-MSCs were detected. The C-Jun N-terminal kinase/nuclear factor-kappa B signaling pathway was studied. Results: The hUC-MSCs treatment decreased the levels of serum alanine aminotransferase and aspartate aminotransferase, reduced pathological damage, alleviated hepatocyte apoptosis, and reduced mortality in vivo. The hUC-MSCs co-culture reduced the apoptosis rate of AML12 cells in vitro. Moreover, lipopolysaccharide-stimulated RAW264.7 cells had higher levels of tumor necrosis factor-α, interleukin-6, and interleukin-1ß and showed more CD86-positive cells, whereas the hUC-MSCs co-culture reduced the levels of the three inflammatory cytokines and increased the ratio of CD206-positive cells. The hUC-MSCs treatment inhibited the activation of phosphorylated (p)-C-Jun N-terminal kinase and p-nuclear factor-kappa B not only in liver tissues but also in AML12 and RAW264.7 cells co-cultured with hUC-MSCs. Conclusions: hUC-MSCs could alleviate ALF by regulating hepatocyte apoptosis and macrophage polarization, thus hUC-MSC-based cell therapy may be an alternative option for patients with ALF.

Perioperative complications of middle cerebral artery occlusion in rats alleviated by human umbilical cord mesenchymal stem cells.

For acute ischemic stroke treatment, the limitations of treatment methods and the high incidence of perioperative complications seriously affect the survival rate and postoperative recovery of patients. Human umbilical cord mesenchymal stem cells (hucMSCs) have multi-directional differentiation potential and immune regulation function, which is a potential cell therapy. The present investigation involved developing a model of cerebral ischemia-reperfusion injury by thrombectomy after middle cerebral artery occlusion (MCAO) for 90 min in rats and utilizing comprehensive multi-system evaluation methods, including the detection of brain tissue ischemia, postoperative survival rate, neurological score, anesthesia recovery monitoring, pain evaluation, stress response, and postoperative pulmonary complications, to elucidate the curative effect of tail vein injection of hucMSCs on MCAO's perioperative complications. Based on our research, it has been determined that hucMSCs treatment can reduce the volume of brain tissue ischemia, promote the recovery of neurological function, and improve the postoperative survival rate of MCAO in rats. At the same time, hucMSCs treatment can prolong the time of anesthesia recovery, relieve the occurrence of delirium during anesthesia recovery, and also have a good control effect on postoperative weight loss, facial pain expression, and lung injury. It can also reduce postoperative stress response by regulating blood glucose and serum levels of stress-related proteins including TNF-α, IL-6, CRP, NE, cortisol, ß-endorphin, and IL-10, and ultimately promote the recovery of MCAO's perioperative complications.

Repair Effect of Umbilical Cord Mesenchymal Stem Cells Embedded in Hydrogel on Mouse Insulinoma 6 Cells Injured by Streptozotocin.

Umbilical cord mesenchymal stem cells (UC-MSCs) possess the capabilities of differentiation and immune modulation, which endow them with therapeutic potential in the treatment of type 2 diabetes mellitus (T2DM). In this study, to investigate the repair mechanism of UC-MSCs in hydrogel on pancreatic ß-cells in diabetes, mouse insulinoma 6 (MIN-6) cells damaged by streptozotocin (STZ) in vitro were used in co-culture with UC-MSCs in hydrogel (UC-MSCs + hydrogel). It was found that UC-MSCs + hydrogel had a significant repair effect on injured MIN-6 cells, which was better than the use of UC-MSCs alone (without hydrogel). After repair, the expression of superoxide dismutase (SOD) and catalase (CAT) as well as the total antioxidant capacity (T-AOC) of the repaired MIN-6 cells were increased, effectively reducing the oxidative stress caused by STZ. In addition, UC-MSCs + hydrogel were able to curb the inflammatory response by promoting the expression of anti-inflammatory factor IL-10 and reducing inflammatory factor IL-1ß. In addition, the expression of both nuclear antigen Ki67 for cell proliferation and insulin-related genes such as Pdx1 and MafA was increased in the repaired MIN-6 cells by UC-MSCs + hydrogel, suggesting that the repair effect promotes the proliferation of the injured MIN-6 cells. Compared with the use of UC-MSCs alone, UC-MSCs + hydrogel exhibit superior antioxidant stress resistance against injured MIN-6 cells, better proliferation effects and a longer survival time of UC-MSCs because the porous structure and hydrophilic properties of the hydrogel could affect the growth of cells and slow down their metabolic activities, resulting in a better repair effect on the injured MIN-6 cells.

Stimulation of mouse hair regrowth by exosomes derived from human umbilical cord mesenchymal stem cells.

BACKGROUND: There is an urgent need for new treatments to solve hair loss problem. As mesenchymal stem cells were proved to have effects on promoting tissue repair and regeneration, in which the exosome plays a vital role, we aim to investigate the influence of umbilical cord mesenchymal stem cells exosome (UCMSC-Exos) on hair growth and its mechanism. METHODS: The hUCMSC-Exos were extracted by ultracentrifugation. Primary fibroblasts were cultured with or without hUCMSC-Exos and cell proliferation was evaluated by CCK-8 assay. C57BL/6 mice model of depilation-induced hair regrowth was treated with either hUCMSC-Exos (200 µg/mL) or PBS on one side of the dorsal back. Real time quantitative PCR, flow cytometry analysis, immunohistochemistry and Immunofluorescent staining were used to analyze the regulative effect of hUCMSC-Exos on hair follicle stem/progenitor cells and Wnt/ß-catenin pathway. RESULTS: The proliferation of fibroblasts incubated with hUCMSC-Exos at the concentration of 200 µg/mL was greater than other groups. Treatment with hUCMSC-Exos resulted in rapid reentry into anagen. Hair follicle stem/progenitor cell markers (K15, Lgr5, Lgr6, CD34 and Lrig1) and Wnt/ß-catenin pathway related factors (Wnt5, Lef1, Lrp5 and ß-catenin) were increased in hUCMSC-Exos-injected region. CONCLUSION: hUCMSC-Exos promote fibroblasts proliferation and accelerate mouse hair regrowth by upregulating hair follicle stem/progenitor cell and Wnt/ß-catenin pathway, which suggests potential therapeutic approaches for hair loss disorders.

Dimethyloxallyl Glycine Preconditioning Promotes the Anti-inflammatory and Anti-fibrotic Effects of Human Umbilical Cord Mesenchymal Stem Cells on Kidney Damage in Systemic Lupus Erythematosus Related to TGF-ß/Smad Signaling Pathway.

Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease lacking effective treatments without adverse effects. Dimethyloxallyl glycine (DMOG) enhanced mesenchymal stem cells (MSC) capabilities, but it remains unclear how DMOG-pretreatment of MSCs augments their SLE treatment. Here, we explore the therapeutic potential of DMOG-pretreated human umbilical cord MSCs (hUC-MSCs) in a mouse lupus nephritis (LN) model. In vitro experiments showed that DMOG could alleviate the mRNA levels of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and interleukin (IL)-6 and increase the mRNA level of IL-13 in lipopolysaccharide (LPS)-induced inflammation in hUC-MSCs. DMOG enhanced the migratory and invasive abilities of the hUC-MSCs. In vivo animal studies revealed that DMOG-pretreated hUC-MSCs exhibited more pronounced inhibition of lymphadenectasis and reduced kidney weight and urinary protein content than MSCs alone. DMOG-pretreated hUC-MSCs improved renal morphological structure and alleviated inflammatory cell infiltration and renal fibrosis, evidenced by the reduced mRNA levels of fibrosis markers, including fibronectin (Fn), collagen alpha-1 chain (Colα1), collagen alpha-3 chain (Colα3), and TNF-α, IFN-γ, and IL-6 cytokines. Further investigation revealed that DMOG-pretreated hUC-MSCs down-regulated the expressions of transforming growth factor (Tgf)-ß1 and its downstream effectors Smad2 and Smad3, recognized as central mediators in renal fibrosis (P < 0.05). The findings suggest that DMOG-pretreated hUC-MSCs can augment the therapeutic efficacy of hUC-MSCs in LN by enhancing their anti-inflammatory and antifibrotic effects, and the TGF-ß/Smad signaling pathway may be involved in this process.

Gelatin-Based Scaffolds with Carrageenan and Chitosan for Soft Tissue Regeneration.

Motivated by the enormous potential of hydrogels in regenerative medicine, new biocompatible gelatin-based hybrid hydrogels were developed through a green process using poly(ethylene glycol) diglycidyl ether as a cross-linking agent, adding carrageenan and chitosan polysaccharides to the network to better mimic the hybrid composition of native extracellular matrix. Overall, the hydrogels show suitable structural stability, high porosity and pore interconnectivity, good swellability, and finally, biocompatibility. Their mechanical behavior, investigated by tensile and compression tests, appears to be characterized by nonlinear elasticity with high compliance values, fast stress-relaxation, and good strain reversibility with no sign of mechanical failure for compressive loading-unloading cycles at relatively high deformation levels of 50%. Degradation tests confirm the hydrogel bioresorbability by gradual hydrolysis, during which the structural integrity of both materials is maintained, while their mechanical behavior becomes more and more compliant. Human Umbilical Cord-derived Mesenchymal Stem Cells (hUC-MSCs) were used to test the hydrogels as potential carriers for cell delivery in tissue engineering. hUC-MSCs cultured inside the hydrogels show a homogenous distribution and maintain their growth and viability for at least 21 days of culture, with an increasing proliferation trend. Hence, this study contributes to a further understanding of the potential use of hybrid hydrogels and hUC-MSCs for a wide range of biomedical applications, particularly in soft tissue engineering.

Human umbilical cord mesenchymal stem cell-based gene therapy for hemophilia B using scAAV-DJ/8-LP1-hFIXco transduction.

BACKGROUND: Hemophilia B is an X-linked bleeding disorder caused by a mutation in the gene responsible for encoding coagulation factor IX (FIX). Gene therapy offers promising potential for curing this disease. However, the current method of relatively high dosage of virus injection carries inherent risks. The purpose of this study was to introduce a novel scAAV-DJ/8-LP1-hFIXco vector transduced human umbilical cord blood derived mesenchymal stem cells (HUCMSCs) as an alternative cell-based gene therapy to conventional gene therapy for Hemophilia B. METHODS: The LP1-hFIXco gene structure was designed by us through searching the literature from NCBI and the scAAV-DJ/8-LP1-hFIXco vector was constructed by a commercial company. The HUCMSCs were cultivated in routine approach and transduced with scAAV-DJ/8-LP1-hFIXco vector. The human FIX activation system was employed for detection of hFIXco activity. The RNA and protein expression levels of the hFIXco were evaluated using PCR and western blot techniques. In animal studies, both NSG and F9-KO mice were used for the experiment, in which clotting time was utilized as a parameter for bleeding assessment. The immunohistochemical analysis was used to assess the distribution of HUCMSCs in mouse tissue sections. The safety for tumorigenicity of this cell-based gene therapy was evaluated by pathological observation after hematoxylin-eosin staining. RESULTS: The transduction of HUCMSCs with the scAAV-DJ/8-LP1-hFIXco vector results in consistent and sustainable secretion of human FIXco during 5 months period both in vitro and in mouse model. The secretion level (hFIXco activity: 97.1 ± 2.3% at day 7 to 48.8 ± 4.5% at 5 months) was comparable to that observed following intravenous injection with a high dose of the viral vector (hFIXco activity: 95.2 ± 2.2% to 40.8 ± 4.3%). After a 5-month observation period, no clonal expansions of the transduced cells in tissues were observed in any of the mice studied. CONCLUSIONS: We have discovered a novel and safer HUCMSCs mediated approach potentially effective for gene therapy in hemophilia B.

Human umbilical cord mesenchymal stem cells derived-exosomes on VEGF-A in hypoxic-induced mice retinal astrocytes and mice model of retinopathy of prematurity.

AIM: To observe the effect of human umbilical cord mesenchymal stem cells (hUCMSCs) secretions on the relevant factors in mouse retinal astrocytes, and to investigate the effect of hUCMSCs on the expression of vascular endothelial growth factor-A (VEGF-A) and to observe the therapeutic effect on the mouse model of retinopathy of prematurity (ROP). METHODS: Cultured hUCMSCs and extracted exosomes from them and then retinal astrocytes were divided into control group and hypoxia group. MTT assay, flow cytometry, reverse transcription-polymerase chain reaction (RT-PCR) and Western blot were used to detect related indicators. Possible mechanisms by which hUCMSCs exosomes affect VEGF-A expression in hypoxia-induced mouse retinal astrocytes were explored. At last, the efficacy of exosomes of UCMSCs in a mouse ROP model was explored. Graphpad6 was used to comprehensively process data information. RESULTS: The secretion was successfully extracted from the culture supernatant of hUCMSCs by gradient ultracentrifugation. Reactive oxygen species (ROS) and hypoxia inducible factor-1α (HIF-1α) of mice retinal astrocytes under different hypoxia time and the expression level of VEGF-A protein and VEGF-A mRNA increased, and the ROP cell model was established after 6h of hypoxia. The secretions of medium and high concentrations of hUCMSCs can reduce ROS and HIF-1α, the expression levels of VEGF-A protein and VEGF-A mRNA are statistically significant and concentration dependent. Compared with the ROP cell model group, the expression of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signal pathway related factors in the hUCMSCs exocrine group is significantly decreased. The intravitreal injection of the secretions of medium and high concentrations of hUCMSCs can reduce VEGF-A and HIF-1α in ROP model tissues. HE staining shows that the number of retinal neovascularization in ROP mice decreases with the increase of the dose of hUCMSCs secretion. CONCLUSION: In a hypoxia induced mouse retinal astrocyte model, hUCMSCs exosomes are found to effectively reduce the expression of HIF-1α and VEGF-A, which are positively correlated with the concentration of hUCMSCs exosomes. HUCMSCs exosomes can effectively reduce the number of retinal neovascularization and the expression of HIF-1α and VEGF-A proteins in ROP mice, and are positively correlated with drug dosage. Besides, they can reduce the related factors on the PI3K/AKT/mTOR signaling pathway.

Exosomes from umbilical cord mesenchymal stem cells ameliorate intervertebral disc degeneration via repairing mitochondrial dysfunction.

Background: Reactive oxygen species (ROS), predominantly generated by mitochondria, play a crucial role in the pathogenesis of intervertebral disc degeneration (IVDD). Reduction of ROS levels may be an effective strategy to delay IVDD. In this study, we assessed whether umbilical cord mesenchymal stem cell-exosomes (UCMSC-exos) can be used to treat IVDD by suppressing ROS production caused by mitochondrial dysfunction. Materials and methods: Human UCMSC-exos were isolated and identified. Nucleus pulposus cells (NPCs) were stimulated with H2O2 in the presence or absence of exosomes. Then, 4D label free quantitative (4D-LFQ) proteomics were used to analyze the differentially expressed (DE) proteins. Mitochondrial membrane potential (MMP), mitochondrial ROS and protein levels were determined via immunofluorescence staining, flow cytometry and western blotting respectively. Additionally, high-throughput sequencing was performed to identify the DE miRNAs in NPCs. Finally, therapeutic effects of UCMSC-exos were investigated in a puncture-induced IVDD rat model. Degenerative grades of rat IVDs were assessed using magnetic resonance imaging and histochemical staining. Results: UCMSC-exos effectively improved the viability of NPCs and restored the expression of the extracellular matrix (ECM) proteins, collagen type II alpha-1 (COL2A1) and matrix metalloproteinase-13 induced by H2O2. Additionally, UCMSC-exos not only reduced the total intracellular ROS and mitochondrial superoxide levels, but also increased MMP in pathological NPCs. 4D-LFQ proteomics and western blotting further revealed that UCMSC-exos up-regulated the levels of the mitochondrial protein, mitochondrial transcription factor A (TFAM), in H2O2-induced NPCs. High-throughput sequencing and qRT-PCR uncovered that UCMSC-exos down-regulated the levels of miR-194-5p, a potential negative regulator of TFAM, induced by H2O2. Finally, in vivo results showed that UCMSC-exos injection improved the histopathological structure and enhanced the expression levels of COL2A1 and TFAM in the rat IVDD model. Conclusions: Our findings suggest that UCMSC-exos promote ECM synthesis, relieve mitochondrial oxidative stress, and attenuate mitochondrial dysfunction in vitro and in vivo, thereby effectively treating IVDD. The translational potential of this article: This study provides solid experimental data support for the therapeutic effects of UCMSC-exos on IVDD, suggesting that UCMSC-exos will be a promising nanotherapy for IVDD.

3D-hUMSCs Exosomes Ameliorate Vitiligo by Simultaneously Potentiating Treg Cells-Mediated Immunosuppression and Suppressing Oxidative Stress-Induced Melanocyte Damage.

Vitiligo is an autoimmune disease characterized by epidermal melanocyte destruction, with abnormal autoimmune responses and excessive oxidative stress as two cardinal mechanisms. Human umbilical mesenchymal stem cells-derived exosomes (hUMSCs-Exos) are regarded as promising therapeutic choice for autoimmune diseases due to potent immunosuppressive and anti-oxidative properties, which can be potentiated under 3D cell culture condition. Nevertheless, whether exosomes derived from 3D spheroids of hUMSCs (3D-Exos) exhibit considerable therapeutic effect on vitiligo and the underlying mechanism remain elusive. In this study, systemic administration of 3D-Exos showed a remarkable effect in treating mice with vitiligo, as revealed by ameliorated skin depigmentation, less CD8+T cells infiltration, and expanded Treg cells in skin, and 3D-Exos exerted a better effect than 2D-Exos. Mechanistically, 3D-Exos can prominently facilitate the expansion of Treg cells in vitiligo lesion and suppress H2O2-induced melanocytes apoptosis. Forward miRNA profile analysis and molecular experiments have demonstrated that miR-132-3p and miR-125b-5p enriched in 3D-Exos greatly contributed to these biological effects by targeting Sirt1 and Bak1 respectively. In aggregate, 3D-Exos can efficiently ameliorate vitiligo by simultaneously potentiating Treg cells-mediated immunosuppression and suppressing oxidative stress-induced melanocyte damage via the delivery of miR-132-3p and miR-125b-5p. The employment of 3D-Exos will be a promising treament for vitiligo.

Umbilical Cord Mesenchymal Stem Cells Combined with Fufang Xueshuantong Capsule Attenuate Oxidative Stress and Vascular Lesions in Diabetic Rats by Activating Nrf-2/HO-1 Signaling Pathway.

BACKGROUND: Macrovascular lesions are the main cause of death and disability in diabetes mellitus, and excessive accumulation of cholesterol and lipids can lead to long-term and repeated damage of vascular endothelial cells. Umbilical cord mesenchymal stem cells (UCMSCs) can attenuate vascular endothelial damage in type 1 diabetic mice, while Fufang Xueshuantong capsule (FXC) has a protective effect on endothelial function; however, whether FXC in combination with UCMSCs can improve T2DM macrovascular lesions as well as its mechanism of action are not clear. Therefore, the aim of this study was to reveal the role of FXC + UCMSCs in T2DM vasculopathy and their potential mechanism in the treatment of T2DM. METHODS: The control and T2DM groups were intragastrically administered with equal amounts of saline, the UCMSCs group was injected with UCMSCs (1×106, resuspended cells with 0.5 mL PBS) in the tail vein, the FXC group was intragastrically administered with 0.58 g/kg FXC, and the UCMSCs + FXC group was injected with UCMSCs (1×106) in the tail vein, followed by FXC (0.58 g/kg), for 8 weeks. RESULTS: We found that FXC+UCMSCs effectively reduced lipid levels (TG, TC, and LDL-C) and ameliorated aortic lesions in T2DM rats. Meanwhile, Nrf2 and HO-1 expression were upregulated. We demonstrated that inhibition of Nrf-2 expression blocked the inhibitory effect of FXC+UCMSCs-CM on apoptosis and oxidative stress injury. CONCLUSION: Our data suggest that FXC+UCMSCs may attenuate oxidative stress injury and macroangiopathy in T2DM by activating the Nrf-2/HO-1 pathway.

Human umbilical cord mesenchymal stem cells combined with porcine small intestinal submucosa promote the healing of full-thickness skin injury in SD rats.

Aim: To assess the therapeutic potential of human umbilical cord mesenchymal stem cells (hUCMSCs) combined with porcine small intestinal submucosa (SIS) on full-thickness skin injuries in rats. Methods: We established full-thickness skin injury models in Sprague-Dawley rats, dividing them into blank control, SIS, hUCMSCs and hUCMSCs combined with SIS. We monitored wound healing, scores and area, and analyzed inflammatory cells, microvessel density and collagen fibers after 12 days. Results: The blank group showed no healing, forming a scar of 0.6 × 0.5 cm2, while SIS and hUCMSCs groups exhibited incomplete healing with 0.4 × 0.5 cm2 scabs. Wound healing was significantly better in the hUCMSCs combined with the SIS group. Conclusion: Local application of hUCMSCs combined with SIS enhances full-thickness skin injury wound healing in rats.

Our skin protects us from infections and injuries, but severe damage can lead to health problems. In this study, we explored a promising new treatment to enhance skin healing. We used mesenchymal stem cells derived from umbilical cords in combination with a biological material called porcine small intestinal submucosa (SIS) to conduct experiemnts on rats with skin wounds. This treatment led to much better healing in rats with deep skin wounds compared with standard approaches. This approach is promising for treating severe skin injuries, offering hope for quicker recovery and better outcome, including faster recovery, reduced pain and inflammation and less scarring.

Human umbilical cord mesenchymal stem cells promote steroid-induced osteonecrosis of the femoral head repair by improving microvascular endothelial cell function.

Recently, there has been growing interest in using cell therapy through core decompression (CD) to treat osteonecrosis of the femoral head (ONFH). Our study aimed to investigate the effectiveness and mechanism of human umbilical cord mesenchymal stem cells (hUCMSCs) in treating steroid-induced ONFH. We constructed a steroid-induced ONFH rabbit model as well as dexamethasone (Dex)-treated bone microvascular endothelial cells (BMECs) model of human femoral head. We injected hUCMSCs into the rabbit femoral head via CD. The effects of hUCMSCs on steroid-induced ONFH rabbit model and Dex-treated BMECs were evaluated via micro-CT, microangiography, histology, immunohistochemistry, wound healing, tube formation, and western blotting assay. Furthermore, we conducted single-cell RNA sequencing (scRNA-seq) to examine the characteristics of endothelial cells, the activation of signaling pathways, and inter-cellular communication in ONFH. Our data reveal that hUCMSCs improved the femoral head microstructure and bone repair and promoted angiogenesis in the steroid-induced ONFH rabbit model. Importantly, hUCMSCs improved the migration ability and angioplasty of Dex-treated BMECs by secreting COL6A2 to activate FAK/PI3K/AKT signaling pathway via integrin α1ß1.

A novel approach in biomedical engineering: The use of polyvinyl alcohol hydrogel encapsulating human umbilical cord mesenchymal stem cell-derived exosomes for enhanced osteogenic differentiation and angiogenesis in bone regeneration.

Developing effective methods for alveolar bone defect regeneration is a significant challenge in orthopedics. Exosomes from human umbilical cord mesenchymal stem cells (HUMSC-Exos) have shown potential in bone repair but face limitations due to undefined application methods and mechanisms. To address this, HUMSC-Exos were encapsulated in polyvinyl alcohol (PVA) hydrogel (Exo@PVA) to create a novel material for alveolar bone repair. This combination enhanced the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and human umbilical vein endothelial cells (HUVECs) more effectively than Exos alone. Additionally, Exo@PVA significantly improved alveolar bone regeneration and defect repair in rats. The microRNA-21-5p (miR-21-5p) in Exo@PVA, identified through the GEO database and analyzed via in silico methods, played a crucial role. miR-21-5p promoted BMSC osteogenic differentiation by inhibiting WWP1-mediated KLF5 ubiquitination and enhanced HUVEC angiogenesis by targeting ATP2B4. These findings underscore the potential of an Exo-based approach with PVA hydrogel scaffolds for bone defect repair, operating through the miR-21-5p/WWP1/ATP2B4 signaling axis.

Primed IFN-γ-Umbilical Cord Stem Cells Ameliorate Temporomandibular Joint Osteoarthritis.

Temporomandibular joint osteoarthritis (TMJOA) is a degenerative disorder affecting the temporomandibular joint (TMJ), marked by persistent inflammation and structural damage to the joint. Only symptomatic treatment is available for managing TMJOA. Human umbilical cord mesenchymal stem cells (hUC-MSCs) show potential for treating TMJOA via their immune-modulating actions in the disease area. In addition, stimulation of inflammatory cytokines such as interferon-gamma in hUC-MSCs improves the therapeutic activity of naïve stem cells. Emerging evidence indicates that macrophages play significant roles in regulating joint inflammation through diverse secreted mediators in the pathogenesis of TMJOA. This study was conducted to evaluate the effects of inflammatory cytokine-stimulated hUC-MSCs in repairing TMJOA-induced cartilage lesions and the role of macrophages in the disease. Our in vitro data showed that stimulated hUC-MSCs induce M2 polarization of macrophages and enhance the expression of anti-inflammatory molecules. These effects were subsequently validated in vivo. In a rat model of TMJOA, stimulated hUC-MSCs ameliorated inflammation and increased M2 macrophages ratio. Our results indicate that hUC-MSCs stimulated by inflammatory cytokines modulate the activation of M2 macrophages, thereby shifting the local osteoarthritis microenvironment toward a prochondrogenic state and facilitating cartilage repair in inflammatory conditions. Stimulating hUC-MSCs with inflammatory cytokines could potentially offer an effective therapeutic approach for TMJOA, with macrophages playing a pivotal role in immune modulation.

MSC microvesicles loaded G-quadruplex-enhanced circular single-stranded DNA-9 inhibits tumor growth by targeting MDSCs.

BACKGROUND: Myeloid-derived suppressor cells (MDSCs) promote tumor growth, metastasis, and lead to immunotherapy resistance. Studies revealed that miRNAs are also expressed in MDSCs and promote the immunosuppressive function of MDSCs. Currently, few studies have been reported on inducible cellular microvesicle delivery of nucleic acid drugs targeting miRNA in MDSCs for the treatment of malignant tumors. RESULTS AND CONCLUSION: In this study, we designed an artificial DNA named G-quadruplex-enhanced circular single-stranded DNA-9 (G4-CSSD9), that specifically adsorbs the miR-9 sequence. Its advanced DNA folding structure, rich in tandem repeat guanine (G-quadruplex), also provides good stability. Mesenchymal stem cells (MSCs) were prepared into nanostructured vesicles by membrane extrusion. The MSC microvesicles-encapsulated G4-CSSD9 (MVs@G4-CSSD9) was delivered into MDSCs, which affected the downstream transcription and translation process, and reduced the immunosuppressive function of MDSCs, so as to achieve the purpose of treating melanoma. In particular, it provides an idea for the malignant tumor treatment.

Human Umbilical Cord Mesenchymal Stem Cell-derived Exosome Regulates Intestinal Type 2 Immunity.

AIMS: The aim of this study was to investigate the role of human umbilical cord mesenchymal stem cell-derived exosomes (hUCMSC-Exo) in regulating the intestinal type 2 immune response for either protection or therapy. BACKGROUND: hUCMSC-Exo was considered a novel cell-free therapeutic product that shows promise in the treatment of various diseases. Type 2 immunity is a protective immune response classified as T-helper type 2 (Th2) cells and is associated with helminthic infections and allergic diseases. The effect of hUCMSC-Exo on intestinal type 2 immune response is not clear. METHOD: C57BL/6 mice were used to establish intestinal type 2 immune response by administering of H.poly and treated with hUCMSC-Exo before or after H.poly infection. Intestinal organoids were isolated and co-cultured with IL-4 and hUCMSC-Exo. Then, we monitored the influence of hUCMSC-Exo on type 2 immune response by checking adult worms, the hyperplasia of tuft and goblet cells. RESULT: hUCMSC-Exo significantly delays the colonization of H.poly in subserosal layer of duodenum on day 7 post-infection and promotes the hyperplasia of tuft cells and goblet cells on day 14 post-infection. HUCMSC-Exo enhances the expansion of tuft cells in IL-4 treated intestinal organoids, and promotes lytic cell death. CONCLUSION: Our study demonstrates hUCMSC-Exo may benefit the host by increasing the tolerance at an early infection stage and then enhancing the intestinal type 2 immune response to impede the helminth during Th2 priming. Our results show hUCMSC-Exo may be a positive regulator of type 2 immune response, suggesting hUCMSC-Exo has a potential therapeutic effect on allergic diseases.

Human Umbilical Cord Mesenchymal Stem Cells Derived Exosomes Improved The Aged Mouse IVM Oocytes Quality.

During assisted reproductive technology (ART) treatment, the aged women, especially those over 35 years old, have fewer mature oocytes and poorer quality of the oocytes comparing with the young women. In vitro maturation (IVM) technology facilitates the usage of immature oocytes, which is clinically important for the aged women. However, the maturation rate is low for the oocytes from the aged women. Human umbilical cord mesenchymal stem cells derived exosomes (HUCMSCs-exosomes), as important mediators of intercellular communication, have been widely used to restore ovarian function and improve female fertility. In this study, we isolated HUCMSCs-exosomes and collected the immature germinal vesicle oocytes from the naturally aged mouse model. And we added these HUCMSCs-exosomes to the conventional IVM culture system. The effects of HUCMSCs-exosomes on IVM oocytes were observed and analyzed from multiple aspects including maturation rate, spindle morphology, mitochondria function, and development potential. We found the quality of oocytes was improved by HUCMSCs-exosomes. Based on the results, we propose that HUCMSCs-exosomes may provide a novel and cell free strategy in the improvement of the IVM in elderly infertile women in the future.