Bone Marrow Mesenchymal Stem Cells Research Articles

Bone marrow mesenchymal stem cells modulate miR-202-3p to suppress neuronal apoptosis following spinal cord injury through autophagy activation via the AMPK, MAPK, and PI3K/AKT/mTOR signaling pathway

Bone marrow mesenchymal stem cells (BMMSCs) have garnered attention as promising therapeutic modalities for spinal cord injury (SCI) due to their neuroregenerative, anti-apoptotic, and functional recovery-enhancing properties. The central role of microRNAs (miRNAs) in mediating the beneficial outcomes resulting from BMMSCs in SCI has been highlighted in recent studies, suggesting that targeted modulation of specific miRNAs holds potential for augmenting SCI recovery. Our previous investigation implicated miR-202-3p in the reparative processes of injured spinal cords, although the precise mechanistic underpinnings remain elusive. In vivo, BMMSCs were administered to SCI rats, while in vitro, miR-202-3p was transfected into PC-12 cells. Motor capabilities recovery was assessed via Basso-Beattie-Bresnahan (BBB) scores and footprinting tests; the evaluation of neuronal and spinal cord tissue repair was conducted using Nissl staining, TUNEL staining, hematoxylin and eosin (HE) staining, and immunofluorescence; and the impacts of miR-202-3p on cellular autophagy, neuronal apoptosis, and relevant pathways were evaluated using Western blotting, quantitative polymerase chain reaction (qPCR), and transmission electron microscopy (TEM). Functionally, BMMSCs utilized miR-202-3p to improve motor recovery in SCI rats. Histopathologically, they contributed to the repair of damaged spinal cords and the regeneration of nerve axons. At the molecular level, BMMSCs stimulated autophagy and suppressed neuronal apoptosis by regulating the AMPK, MAPK, and PI3K/AKT/mTOR pathway. Collectively, our findings demonstrate that BMMSCs coordinate miR-202-3p to inhibit mTOR activation via the AMPK, MAPK, and PI3K/AKT pathways, thereby promoting TFEB dephosphorylation, modulating autophagy and neuronal apoptosis, and ultimately fostering functional recovery post-SCI.

CX43-mediated mitochondrial transfer maintains stemness of KG-1a leukemia stem cells through metabolic remodeling

BackgroundAcute myeloid leukemia (AML) is characterized by abundant immature myeloid cells, relapse and refractory due to leukemia stem cells (LSCs). Bone marrow mesenchymal stem/ stromal cells (BMSCs) supported LSCs survival, meanwhile, chemotherapy improved connexin43 (CX43) expression. CX43, as the most intercellular gap junction, facilitated transmit mitochondria from BMSCs into AML. We hypothesized that increased mitochondria transferred from BMSCs supported metabolic remodeling in LSCs to sustain their stemness.MethodsPrimary BMSCs from AML patients were isolated. CX43-BMSCs, overexpressing CX43, were cocultured with KG-1a cells. Fluorescence and confocal microscopy observed mitochondrial transfer. Flow cytometry, EdU assay, and clonogenicity evaluated cell cycle, proliferation, and clonogenic potential. Xenograft mouse models were used to evaluate the tumorigenicity of KG-1a in vivo. Seahorse, RNA-seq, and LC-MS assessed mitochondrial function, transcriptomes, and metabolites post-coculture.ResultsCX43-BMSCs promoted unidirectional mitochondrial transfer, enhancing KG-1a adhesion and proliferation to maintain LSCs stemness in vitro and vivo. RNA-seq revealed coculture with CX43-BMSCs upregulated genes related to adhesion, proliferation, and migration in KG-1a cells. Elevated CX43 expression strengthened BMSCs-KG-1a interaction, facilitating mitochondrial transfer and nucleoside metabolism, fueling KG-1a cells. This enhanced mitochondrial energy metabolism, promoting metabolic reprogramming and clonogenicity.ConclusionCX43-mediated mitochondrial transfer from BMSCs to KG-1a enhances LSCs adhesion, proliferation, clonogenicity, and metabolic reprogramming. CX43 emerges as a potential therapeutic target for AML by sustaining LSCs stemness through metabolic remodeling.

FOXA1 knockdown alleviates inflammation and enhances osteogenic differentiation of periodontal ligament stem cells via STAT3 pathway

BackgroundEvidence has confirmed that forkhead box protein A1 (FOXA1) inhibits the osteogenic differentiation of bone marrow mesenchymal stem cells. However, whether FOXA1 regulates the osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) to participate in periodontitis process is unclear.MethodsLipopolysaccharide (LPS) was used to treat hPDLSCs to mimic inflammation environments. FOXA1 expression was examined by quantitative real-time PCR and western blot. The levels of IL-6 and TNF-α were evaluated by quantitative real-time PCR, ELISA and immunohistochemistry staining. hPDLSCs osteogenic differentiation was assessed by measuring alkaline phosphatase activity, alizarin red S intensity and the levels of osteogenic differentiation-related markers. Besides, the expression of signal transducer and activator of transcription 3 (STAT3) pathway-related markers were examined by western blot and immunofluorescence staining.ResultsFOXA1 was upregulated in the periodontal ligament tissues of periodontitis patients, and its knockdown enhanced osteogenic differentiation of hPDLSCs. Besides, downregulation of FOXA1 suppressed inflammation levels in LPS-induced hPDLSCs. Also, FOXA1 silencing promoted the osteogenic differentiation of LPS-induced hPDLSCs by the inactivation of STAT3 pathway.ConclusionOur data confirmed that knockdown of FOXA1 attenuated inflammation and enhanced osteogenic differentiation of LPS-induced hPDLSCs by regulating STAT3 pathway, indicating that FOXA1 might be a target for periodontitis treatment.

Photobiomodulation therapy at 650 nm enhances osteogenic differentiation of osteoporotic bone marrow mesenchymal stem cells through modulating autophagy

BackgroundPhotobiomodulatiom therapy (PBMT) has biostimulatory effects on bone marrow mesenchymal stem cells (BMSCs), which takes a pivotal role in maintaining bone mass and avoiding osteoporosis (OP). Autophagy is an important regulator for cell survival and homeostasis. Previous researchers found that BMSCs derived from osteoporotic rats (OP-BMSCs) were with the feature of reduced osteogenic differentiation and autophagy dysfunction. However, the potential regulation of PBMT in osteogenic differentiation of OP-BMSCs and its underling relationship with autophagy remain unclear. Methods650 nm red light-emitting diode (LED) was selected to initiate PBMT effects. The isolation and culture of OP-BMSCs were implemented after the establishment of the OP rat model. Firstly, the optimal dose of LED was screened on OP-BMSCs by CCK-8. Meanwhile, the osteogenic and mineralization activities were studied through the detection of Alkaline phosphatase (ALP) and alizarin red S (ARS). Then, the levels of osteogenesis and autophagy were investigated via western blot and immunofluorescence staining. Finally, the autophagy inhibitor 3-MA was applied to illustrate the underlying mechanism of the osteogenic effect of PBMT on OP-BMSCs. ResultsFirstly, the optimal dose of 6 J/cm2 LED was selected in the subsequent experiments according to CCK-8. Then, the ALP activity and the mineralization ability of OP-BMSCs were obviously increased by PBMT. Meanwhile, Runx-2, OCN and OPN were significantly upregulated in LED group. Furthermore, the expressions of autophagic proteins were significantly increased in LED group by immunofluorescence staining and western blot assay. At last, the promoted effects of PBMT on osteogenic differentiation in OP-BMSCs were distinctly reversed via inhibiting autophagy. ConclusionOur research illustrated that 650 nm LED could improve osteogenic differentiation of OP-BMSCs, suggesting a potential correlation between PBMT-mediated activation of autophagy and promotion of osteogenic differentiation.

BMP2 enhance the osteogenic effect of BMSCs-derived exosomes in skull defect of diabetic rats

Diabetic patients often face poor repair of bone defects, which may be related to the reduced osteogenic capacity of bone marrow mesenchymal stem cells (BMSCs) and the polarization of M1/M2 macrophage imbalance leading to an inflammatory response. The ability of BMSC-derived exosomes (BMSC-Exos) and BMP2 to exert both bone tissue regeneration and immunomodulation is expected to resolve this clinical dilemma. In this study, we demonstrate that exosomes derived from BMP2-treated BMSCs (BMP2-Exos) in a diabetic microenvironment exhibit enhanced osteogenic effects. Additionally, compared to the blank control group, macrophages stimulated by BMP2-Exos were more polarized towards the M2 type. These results were verified in vivo by GelMA loaded exosomes in the diabetic rat skull defect model. Importantly, we found that BMP2-Exos can upregulate the PI3K/AKT signaling pathway in diabetic BMSCs and improved osteogenic function and M2 macrophage polarization in diabetes-impaired BMSC-Exos in vitro. In conclusion, the present study revealed that BMP2 pretreatment can enhance the ability of BMSC-Exos to promote osteogenesis in diabetic bone defect areas, provides a preliminary exploration of the underlying mechanisms. Our study provided important experimental basis and innovative ideas for the application of exosomes therapy in the field of bone tissue regeneration.

Amyloid Nanofilm-Induced surface mineralization of 3D-Printed Polyetheretherketone scaffolds for in situ orbital bone regeneration and repair

Orbital bone defect repair is both challenging and crucial and requires the comprehensive consideration of anatomical complexity, functional preservation, aesthetic outcomes, postoperative risks, and long-term effects. Polyetheretherketone (PEEK) is a promising orthopedic substitute material due to its cortical bone-like elastic modulus, biocompatibility, chemical stability, and natural radiolucency. However, PEEK is bioinert and lacks interfacial bioactivity, which limits its ability to promote bone growth and osseointegration. In this study, we fabricated porous PEEK scaffolds using Fused Deposition Modeling (FDM) 3D printing technology. We employed a phase-transitioned lysozyme (PTL) nanofilm as the organic matrix template to construct a robust hydroxyapatite (HAp) coating both inside and outside the porous PEEK scaffold, generating HAp@PTL@PO-PEEK. The PTL nanofilm acted as a strong glue, enhancing the interfacial bonding strength between the HAp coating and PEEK. In vitro cell biology experiments revealed that HAp@PTL@PO-PEEK promoted the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells. Furthermore, the modified scaffolds exhibited excellent osteoconductivity and osteoinductivity in the in vivo repair of rabbit orbital bone defects, promoting new bone formation and guiding new bone growth into the scaffold. Therefore, HAp@PTL@PO-PEEK scaffolds hold potential for clinical craniomaxillofacial bone regeneration and repair.

Optimizing Electroconductive PPy-PCL Scaffolds forEnhanced Tissue Engineering Performance.

The integration of electrically conductive materials is a promising approach in tissue regeneration research. The study presented focuses on the creation of electroconductive scaffolds made from polypyrrole-polycaprolactone (PPy-PCL) using optimal processing parameters. Utilizing Box-Behnken response surface methodology for insitu chemical polymerization of PPy, the scaffolds exhibited a maximum conductivity of 2.542 mS/cm. Morphological examination via scanning electron microscopy (SEM) indicated uniform dispersion of PPy particles within PCL fibers. Fourier transform infrared spectroscopy (FTIR) and energy dispersive x-ray (EDX) analysis validated the composition of the scaffolds, while mechanical testing revealed that the optimized scaffolds exhibit superior tensile strength and Young's modulus compared to scaffolds comprised only of PCL. The hydrophilicity of the scaffolds was improved considerably, transitioning from initially hydrophobic to fully hydrophilic for the optimum scaffold, making it suitable for tissue engineering applications. Cell viability assays, including MTT with L929 fibroblasts and Alamar Blue with bone marrow mesenchymal stem cells (bmMSCs), reflected no cytotoxicity. They showed an increase in metabolic activity, suggesting the capability of the scaffolds to support cellular functions. In conclusion, the insitu synthesis of PPy in the PCL matrix by optimizing the fabrication parameters resulted in conductive scaffolds with promising structural and functional properties for tissue engineering.

Application of miR-29a-Exosome and Multifunctional Scaffold for Full-Thickness Cartilage Defects

BackgroundFull-thickness cartilage defect is a common refractory disease in orthopedics. In this study, we designed a novel composite scaffold composed of silk fibroin-chitosan for the cartilage layer and porous tantalum for the subchondral bone layer, loaded with engineered bone mesenchymal stem cell exosomes, to evaluate its efficacy in repairing full-thickness cartilage defect. MethodsPorous tantalum was 3D printed and combined with silk fibroin-chitosan to form a composite scaffold. Chondrocytes were cultured on the scaffold, and their growth was assessed using the CCK-8 method. Toluidine blue staining confirmed cell morphology, while immunofluorescence revealed collagen type Ⅱ expression. Engineered exosomes loaded with miR-29a were created and characterized using various techniques. Co-culturing with chondrocytes demonstrated their proliferation over 10 days. Immunofluorescence revealed staining for the nucleus, collagen type II, and Aggrecan. In vivo experiments were performed on rats to assess cartilage defect repair, utilizing histological staining and micro-CT scanning at 4 and 8 weeks post-operation. ResultsThe silk fibroin-chitosan scaffold demonstrated good biocompatibility, supporting chondrocyte adhesion, growth, and cartilage tissue formation. Engineered exosomes exhibited promising biological activity, conducive to bone and cartilage regeneration. The implantation of the silk fibroin-chitosan/porous tantalum composite scaffold loaded with engineered exosomes promoted integration with the surrounding bone and cartilage tissues, facilitating repair and regeneration. ConclusionsThe silk fibroin-chitosan combined with porous tantalum scaffold carrying engineered exosomes loaded with miR-29a has good potential for full-thickness cartilage defects regeneration.

MiR-223-3p Promotes Osteoporosis Progression by Repressing Osteogenic Differentiation via Targeting FHL1/Wnt/β-catenin Signaling.

The aim of this research was to unveil the potential along with potential mechanism of miR-223-3p in osteoporosis. RT-qPCR together with western blot was implemented to examine miR-223-3p, FHL1, along with osteogenic markers levels during bone marrow mesenchymal stem cells (BMSCs) differentiation. The ALP activity staining along with alizarin red staining (ARS) were implemented to assess ALP activity as well as the mineralization ability of BMSCs. Binding sequences for miR-223-3p and FHL1 from starBase website were validated through dual-luciferase reporter gene assay. MiR-223-3p was down-regulated in BMSCs during osteoblasts differentiation, and miR-223-3p elevation hindered BMSCs' osteogenic differentiation. FHL1 belonged to the target mRNA of miR-223-3p. FHL1 presented up-regulation in BMSCs during osteoblasts differentiation. More importantly, FHL1 expression was negative modulated by miR-223-3p in BMSCs during osteoblasts differentiation, and FHL1 elevation could inverse the inhibited BMSCs' osteogenic differentiation modulated by miR-223-3p elevation. Furthermore, miR-223-3p elevation repressed the Wnt/β-catenin pathway activity in lithium chloride-treated BMSCs, and FHL1 overexpression counteracted the inhibitory effect of the Wnt/β-catenin pathway caused by miR-223-3p up-regulation. Collectively, miR-223-3p accelerates osteoporosis progression by repressing osteogenic differentiation through targeting FHL1/Wnt/β-catenin signaling.

Protective effects of puerarin combined with bone marrow mesenchymal stem cells on nerve injury in rats with ischemic stroke

ABSTRACT Background Bone marrow mesenchymal stem cells (BM-MSCs) transplantation shows promise for treating ischemic stroke, but the ischemic environment that follows cerebral infarction hinders the survival of transplanted cells. We aimed to study the effects of puerarin (Pue) in combination with BM-MSCs on cerebral ischemic injury. Methods After middle cerebral artery occlusion (MCAO) models were prepared by suture-occluded method, rats were randomly allocated to the sham, MCAO, Pue (50 mg/kg), BM-MSCs (2×106), and BM-MSCs+Pue groups. The neurological function, infarct area, levels of inflammation-related factors, brain tissue damage, apoptosis, BrdU, Beclin1, and LC3 levels were then assessed. Results Pue and BM-MSCs reduced the modified neurological severity score, cerebral infarction area, and serum inflammation-related factor levels for MCAO rats. Furthermore, Pue and BM-MSCs interventions ameliorated brain tissue damage, and repressed apoptosis of brain tissues in MCAO rats. Moreover, Pue or BM-MSCs enhanced BrdU expression, restrained LC3II/LC3I ratio and Beclin 1 expression in MCAO rats’ brain tissues. Importantly, the combination of Pue and BM-MSCs exhibited more pronounced effects on aforementioned outcomes. Conclusion The combination of Pue and BM-MSCs facilitated the recovery of neurological function in rats after cerebral ischemic damage, and the mechanisms may correlate with the repression of neuronal apoptosis, inflammation, and autophagy.

Bone marrow mesenchymal stem cell-derived exosomal miR-181a-5p promotes M2 macrophage polarization to alleviate acute pancreatitis through ZEB2-mediated RACK1 ubiquitination.

As a common digestive disease, acute pancreatitis (AP) often threatens the life of patients. Bone marrow mesenchymal stem cells (BMSCs) derived exosomes have exhibited some benefits for AP. However, the mechanism remains unclear and deserves to be further investigated. The characteristics of BMSCs-exosomes (BMSCs-Exos) were identified. The abundance of genes and proteins was evaluated using quantitative real-time PCR (RT-qPCR), western blot, enzyme-linked immunosorbent assay (ELISA) and IF assay. Cell apoptosis and CD206-positive cells were measured by flow cytometry. The interactions among miR-181a-5p, Zinc finger E-box binding homeobox2 (ZEB2) and Receptor for Activated C Kinase 1 (RACK1) were verified using dual luciferase reporter assay, RNA immunoprecipitation (RIP), coimmunoprecipitation (Co-IP). BMSCs-Exos effectively improved AP injury through restraining AR42J cell apoptosis and promoting M2 macrophage polarization, which was realized due to BMSCs-Exos harboring an abundance of miR-181a-5p. Further experiments validated miR-181a-5p silenced ZEB2 and ZEB2 reduced RACK1 expression through mediating RACK1 ubiquitination. ZEB2 knockdown decreased AR42J cell apoptosis and induced M2 macrophage polarization to alleviate AP injury, whereas RACK1 downregulation abolished these phenomena. BMSCs-Exos harboring miR-181a-5p suppressed AR42J cell apoptosis and promoted M2 macrophage polarization to delay AP progression through ZEB2-mediated RACK1 ubiquitination.

Gold Kiwi-Derived Nanovesicles Mitigate Ultraviolet-Induced Photoaging and Enhance Osteogenic Differentiation in Bone Marrow Mesenchymal Stem Cells

Bone marrow mesenchymal stem cells (BM-MSCs) play a crucial role in bone formation through their ability to differentiate into osteoblasts. Aging, however, detrimentally affects the differentiation and proliferation capacities of BM-MSCs, consequently impairing bone regeneration. Thus, mitigating the aging effects on BM-MSCs is vital for addressing bone-related pathologies. In this study, we demonstrate that extracellular nanovesicles isolated from gold kiwi (GK-NVs) protect human BM-MSCs from ultraviolet (UV)-induced photoaging, thereby alleviating aging-related impairments in cellular functions that are crucial for bone homeostasis. Notably, GK-NVs were efficiently taken up by BM-MSCs without causing cytotoxicity. GK-NVs reduced intracellular reactive oxygen species (ROS) levels upon UV irradiation, restoring impaired proliferation and migration capabilities. Furthermore, GK-NVs corrected the skewed differentiation capacities of UV-irradiated BM-MSCs by enhancing osteoblast differentiation, as evidenced by the increased expression in osteoblast-specific genes and the calcium deposition, and by reducing adipocyte differentiation, as indicated by the decreased lipid droplet formation. These findings position GK-NVs as a promising biomaterial for the treatment of bone-related diseases such as osteoporosis.

Bone marrow mesenchymal stem cells-derived exosomes promote spinal cord injury repair through the miR-497-5p/TXNIP/NLRP3 axis.

Bone marrow mesenchymal stem cells (BMSCs) indicate a repairing prospect to treat spinal cord injury, a major traumatic disease. This study investigated the repair effect of bone marrow mesenchymal stem cell-derived exosomes (BMSC-Exos) on spinal cord injury. BMSCs were collected to extract BMSC-Exos which were identified by different means. The SCI model of rats was established, the motor behavior was scored by BBB field test, and the spinal cord tissues were separated and stained by HE, Nissl, and Tunel, respectively, as well as analyzed to measure inflammatory and oxidative stress responses. PC12 cells were co-cultured with Exos and analyzed by CCK-8 and flow cytometry to measure cell proliferation and apoptosis. BMSC-Exos improved SCI in rats with the recovery of motor function, alleviation of pathological conditions, and reduction of apoptosis, inflammatory responses, and oxidative stress. BMSC-Exos increased miR-497-5p expression, and miR-497-5p overexpression strengthened the protective effect of BMSC-Exos on SCI. miR-497-5p targeted inactivation of TXNIP/NLRP3 pathway. TXNIP saved the repair effect of miR-497-5p-carrying BMSC-Exos on SCI rats. miR-497-5p-carrying BMSC-Exos alleviated apoptosis and induced proliferation of H2O2-treated PC12 cells. BMSC-Exos promote SCI repair via the miR-497-5p/TXNIP/NLRP3 axis, which may be a target for alleviating SCI-associated nerve damage.

Bilobalide Activates Autophagy and Enhances the Efficacy of Bone Marrow Mesenchymal Stem Cells on Spinal Cord Injury Via Upregulating FMRP to Promote WNK1 mRNA Decay.

Transplantation of bone marrow mesenchymal stem cells (BMSCs) represents an encouraging strategy for the repair of spinal cord injury (SCI), however, its effectiveness on treating SCI remains controversial. Bilobalide isolated from Ginkgo biloba leaves shows significant neuroprotective effects. We examined the role and underlying mechanism of bilobalide in the efficacy of BMSC transplantation on SCI. Primary BMSCs were isolated from neonatal rats, and cell viability was assessed by MTT assay. Neuronal markers (MAP-2, NeuN, NSE and Tuj1), autophagy markers (LC3 and Beclin1), and Fragile X mental retardation protein (FMRP)/With-no-lysine kinase-1 (WNK1) signaling were measured using RT-qPCR and western blotting. The relationship of FMRP and WNK1 was estimated by RNA immunoprecipitation, while WNK1 mRNA stability was assessed with actinomycin D assay. In a SCI rat model, tissue injury was examined using HE and Nissl staining. Bilobalide treatment facilitated neural differentiation of BMSCs, as well as enhanced autophagy and inhibited WNK1 signaling. The promotive effect of bilobalide on BMSC differentiation was antagonized when overexpressing WNK1 or inhibiting autophagy. Bilobalide upregulated FMRP to promote WNK1 mRNA decay, thus reducing WNK1 expression. FMRP knockdown reversed the promoted functions of bilobalide on autophagy and neuronal differentiation in BMSCs. Additionally, compared to either monotherapy, simultaneous treatments with bilobalide and BMSCs further facilitated autophagy and neuronal differentiation, thereby enhancing the repair of SCI in rats. Bilobalide enhances autophagy activity to promote BMSC neuronal differentiation via FMRP/WNK1 axis, thus improving functional recovery following SCI, which indicates a promising therapeutic approach for SCI.

Establishment of immortalized rabbit bone marrow mesenchymal stem cells and a preliminary study of their osteogenic differentiation capability.

A stable and standardized source of mesenchymal stem cells is a prerequisite for bone repair tissue engineering research and application. We aimed to establish a stable cell line of bone marrow mesenchymal stem cells from New Zealand rabbits and explore their osteogenic differentiation capacity. Primary rabbit bone marrow mesenchymal stem cells (RBMSCs) were isolated and immortalized via retroviral expression of SV40 Large T antigen (LTA). To assess the osteogenic differentiation capacity of the cells invitro, we studied the alkaline phosphatase (ALP) expression level and calcium deposition in bone morphogenetic protein 9 (BMP9)-induced immortalized cells using ALP staining and quantification, as well as alizarin red staining. Ectopic bone formation by the cells was assessed using micro-computed tomography (μCT) and histological examination. The immortalized cell line we established using SV40 LTA, which we termed iRBMSCs, was non-tumorigenic and maintained long-term proliferative activity. We further discovered that BMP9 (MOI = 30) effectively induced the osteogenic differentiation capacity of iRBMSCs invitro, and there was a synergy with GelMA hydrogel in inducing osteogenic differentiation of the iRBMSCs invivo. We confirmed that iRBMSCs are promising as a stable cell line source for bone defect repair engineering.

IL-10RA governor the expression of IDO in the instruction of lymphocyte immunity.

Indoleamine 2,3-dioxygenase (IDO) impairs anti-pathogen and anti-tumour immunity. Mesenchymal stem cells (MSCs) modulate immunity via IDO but also suppress IFN-γ. While MSC IDO induction by IFN-γ is established, other drivers in this immunosuppressive setting remain unknown. Human bone marrow mesenchymal stem cells (MSCs) with IDO or IL-10RA knockdown were co-cultured with healthy donor T cells to assess immunosuppression. PDAC organoid anticancer activity was also tested in these co-cultures. Co-culturing MSCs with T cells in an IL-10RA-enriched environment enhances IDO expression, resulting in T cell suppression. Moreover, IL-10RA-positive MSCs collected from co-cultures with IL-10 supplementation show increased IDO expression. Conversely, MSCs with IL-10RA knockdown exhibit a significant reduction in IDO RNA and protein expression, as well as STAT3 phosphorylation status, which is a known upstream signalling pathway in IDO gene regulation, in T cell co-cultures. Down-regulation of IL-10RA also inhibits IDO activity in MSCs, resulting in reduced T cell suppression, and enabling the co-cultured T cells to kill PDAC organoids. Our research reveals IL-10RA as a pharmacological target in stromal cells for enhancing T cell-mediated PDAC eradication by downregulating IDO via blocked IL-10/IL-10RA signalling in MSCs. This advances IL-10RA interference in the tumour microenvironment (TME) to restore T cell cytotoxicity against cancers.

Study on the in vitro changes of human bone marrow‑related mesenchymal stem cells.

Bone marrow mesenchymal stem cells (MSCs) serve a pivotal role in the hematopoietic niche. The present study collected bone marrow samples from individuals across various age groups to investigate the biological characteristics of MSCs. By modifying the bone marrow microenvironment through co‑culture techniques, changes in the stemness of MSCs were examined. An in vitro hematopoietic co‑culture system was established to simulate the impact of MSCs on hematopoietic stem cells. The results demonstrated that the mode of cell‑to‑cell contact among stem cells is more influential in shaping bone marrow function compared with the effects of aging on these stem cells. Transcriptomic analysis revealed that MSCs serve as essential mediators, with their growth variations being both a consequence and a cause of changes in the bone marrow microenvironment. Furthermore, the decline in hematopoietic function observed in the elderly is a manifestation of this phenomenon. Data from the present study suggest that targeting MSCs is essential for enhancing bone marrow function and improving the outcomes of bone marrow transplantation.

Intravenous injection of BMSCs modulate tsRNA expression and ameliorate lung remodeling in COPD mice

BackgroundChronic obstructive pulmonary disease (COPD) is characterized by lung remodeling induced by chronic inflammation, presenting challenges for effective treatment. Mesenchymal stem cells (MSCs) and their extracellular vesicles (EVs) have shown promise in mitigating inflammation and tissue repairing in various diseases, including COPD. However, the optimal therapeutic pathways for different stages of COPD remain unclear. Transfer RNA-derived small RNAs (tsRNAs) are emerging as key regulators of cellular processes. However, their role in COPD and MSC therapy remains poorly understood.MethodsThis study explored the optimal administration routes and efficacy of bone marrow mesenchymal stem cells (BMSCs) and their extracellular vesicles (BMSC-EVs) in treating inflammatory or emphysematous COPD stages in mouse models. Male C57BL/6 mice were exposed to cigarette smoke daily for 6 or 16 weeks, with intraperitoneal CSE injections every 10 days, to model different stages of COPD. Mice were then treated with tracheal or intravenous injections of BMSCs or BMSC-EVs. PKH26 fluorescent dye labeled BMSCs and BMSC-EVs for pulmonary distribution observation. Lung tissue inflammation, apoptosis, EMT, and collagen deposition were assessed using HE staining, TUNEL assay, immunohistochemistry, and Sirius Red staining. Gene and tsRNA expression in lung tissues were analyzed by high-throughput sequencing. Differentially expressed tsRNAs (DE-tsRNAs) were validated by RT-qPCR. Statistical analysis was performed using GraphPad Prism 9.0. Data are presented as mean ± standard deviation (SD).ResultsIn 16-week COPD mice characterized by emphysema, tracheal administration of BMSC-EVs showed more significant lung distribution and inhibition of emphysematous pathology. In 6-week COPD mice characterized by inflammation, intravenous injection of BMSCs led to significant pulmonary homing, significantly reduced lung inflammation, apoptosis, EMT, and collagen deposition (P < 0.05). High-throughput sequencing indicated BMSC treatment downregulated genes related to these processes while upregulating mitochondrial function genes. Co-expression networks of DE-tsRNAs and target genes suggested potential roles in COPD. RT-qPCR confirmed significant differential expression of two DE-tsRNAs during COPD progression and BMSC treatment (P < 0.05).ConclusionsOur study provides insights into selecting MSC and MSC-EV administration routes for different COPD stages. High-throughput sequencing supports BMSCs’ inhibitory effects on lung remodeling and identifies the first tsRNA expression profile in a COPD model, warranting further investigation.

Studies on the Role of MAP4K2, SPI1, and CTSD in Osteoporosis.

Osteoporosis (OP) is a prevalent skeletal disorder characterized by an imbalance between bone resorption and bone formation, resulting in a significant global burden. Previous research utilizing bioinformatics analysis has identified MAP4K2, SPI1, and CTSD as hub genes associated with OP. In this current investigation, we have successfully established a differential expression system of MAP4K2, SPI1, and CTSD in rat bone marrow mesenchymal stem cells (BMSCs) through transfection techniques. Additionally, the CCK-8 assay was employed to assess cell proliferation, while the alkaline phosphatase (ALP) activity assay and ALP staining assay were utilized to evaluate osteogenic differentiation. Alizarin red staining was employed to detect mineralization of BMSCs. Furthermore, the expression of relevant genes and molecules associated with the MAPK signaling pathway, autophagy, and apoptosis in the sera of rat BMSCs were examined using quantitative real-time polymerase chain reaction (qRT-PCR). The purpose of this study was to preliminarily investigate whether MAP4K2, SPI1, and CTSD have an effect on the osteogenic capacity of rat BMSCs and whether these genes, when differentially expressed, affect the expression of related genes in the MAPK, autophagy, and apoptosis signaling pathways and thus the osteogenic function of BMSCs. In summary, the findings of this study indicate that MAP4K2 and CTSD exert significant influence on the proliferation, osteogenic differentiation, and mineralization processes of rat BMSCs cells. Furthermore, these proteins may contribute to the development of OP through their involvement in the regulation of autophagy and apoptosis. Conversely, our investigation did not reveal any discernible impact of SPI1 on OP-related phenotypes. Consequently, this research serves as a fundamental basis for further exploration of potential therapeutic targets for the treatment of OP.

Cerium Oxide Nanoparticles-Reinforced GelMA Hydrogel Loading Bone Marrow Stem Cells with Osteogenic and Inflammatory Regulatory Capacity for Bone Defect Repair

Cerium Oxide Nanoparticles-Reinforced GelMA Hydrogel Loading Bone Marrow Stem Cells with Osteogenic and Inflammatory Regulatory Capacity for Bone Defect Repair