The CRISPR/dCas9 system is a gene editing tool that has proven to be highly efficient and precise. By utilizing transcriptional activators, such as VP64, p65, and Rta, the system can effectively and stably activate target genes. Sox17, a transcription factor belonging to the SOX family, plays a crucial role in the differentiation of the germ layers and the determination of cell fates during the early stages of embryonic development. Sheep embryonic stem cells (sESCs) are characterized by their capacity for self-renewal and multidirectional differentiation, serving as a significant in vitro model for studying the mechanisms of cell differentiation during early embryonic development. However, the importing of exogenous genes into sESCs is challenging due to their unique growth characteristics. The objective of this study was to investigate the conditions necessary for successfully activating Sox17 in sESCs. To this end, we employed the CRISPR/dCas9 system along with liposome transfection, lentivirus invasion, and electroporation to activate Sox17 in sESCs. The expression of Sox17 was then determined by fluorescence quantitative PCR, on the basis of which the performance of different transfection methods was compared. The results indicated that the electroporation group had the best transfection effect and the highest Sox17 expression among the three transfection methods. The efficient and stable gene activation protocol will provide a reference for embryonic stem cell research in other species, especially livestock animals, and lay the foundation for the subsequent study of gene function and realization of precise cell fate regulation by regulating gene expression in sheep embryonic stem cells.
Animals ; CRISPR-Cas Systems/genetics* ; Sheep ; SOXF Transcription Factors/genetics* ; Embryonic Stem Cells/cytology* ; Genetic Vectors/genetics* ; Cell Differentiation/genetics* ; Transfection ; Gene Editing/methods*

Mesenchymal stem cells (MSCs) are an effective therapeutic strategy to delay aging in dogs, they are prone to aging and have poor genetic stability when cultured for a long time in vitro. Therefore, it is of great significance to explore a method to improve the anti-aging ability of MSCs. Previous studies have shown that sirtuin 6 (SIRT6) plays an important role in anti-aging. This study constructed MSCs with overexpressed SIRT6 gene. Through Giemsa staining and senescence-associated β-galactosidase staining, it was found that SIRT6 significantly enhances the anti-aging capacity of MSCs. Transmission electron microscopy imaging and the detection of oxidative stress-related indicators revealed that SIRT6 improves the anti-aging capacity of MSCs by maintaining mitochondrial homeostasis and reducing oxidative stress levels. Transcriptome sequencing analysis revealed that SIRT6 mainly acted on phosphatidylinositol-3-kinase, mitogen-activated protein kinase and other aging and inflammation related pathways. In the establishment and verification of aging models in mice and dogs, it was found that the spatial memory ability of the model mice was significantly increased after intravenous transplantation of SIRT6 overexpression cells, the organ index was also significantly changed, and the anti-oxidative capacity of the dogs and mice blood was improved. The morphology of the spleens and livers in the SIRT6 overexpression cell treatment group could be effectively restored, and the expression levels of aging and inflammation-related proteins were significantly decreased. This study provides a new idea for the study of SIRT6-mediated anti-aging of MSCs.
Animals ; Dogs ; Mesenchymal Stem Cells/metabolism* ; Sirtuins/genetics* ; Aging/physiology* ; Mice ; Oxidative Stress ; Mesenchymal Stem Cell Transplantation

Cancer ranks as the second leading cause of death globally and has surpassed cardiovascular diseases to become the primary cause of mortality in developed countries. Cancer stem cells (CSCs), which play crucial roles in cancer recurrence, metastasis, and drug resistance, have attracted significant attention in targeted therapeutic strategies. Aptamers, with unique three-dimensional structures capable of specifically recognizing the surface markers of CSCs, show promising potential in targeted drug delivery systems. Compared with conventional antibodies, aptamers are praised for small molecular weights, low production costs, and easy chemical modification. This review systematically summarizes recent advances in aptamer research targeting the surface markers of CSCs, with particular emphasis on aptamer-drug conjugate systems targeting the markers including EpCAM, CD133, CD44, and ABCG2. Both in vitro cellular studies and in vivo animal models have demonstrated the definite anti-cancer efficacy of aptamer-based drug delivery systems, which are of great significance to develop novel therapeutic strategies and improving the therapeutic effects of CSC-targeted treatment. Thus, aptamer-based drug delivery system has broad application prospects in the field of precise cancer treatment.
Humans ; Neoplastic Stem Cells/metabolism* ; Aptamers, Nucleotide/therapeutic use* ; Drug Delivery Systems/methods* ; Neoplasms/drug therapy* ; Biomarkers, Tumor/metabolism* ; Animals ; Epithelial Cell Adhesion Molecule ; AC133 Antigen ; Hyaluronan Receptors

Organoids are three-dimensional (3D) cellular structures formed through the differentiation and self-organization of pluripotent stem cells or tissue-derived cells, showing considerable potential in the research on disease mechanism, personalized medicine, and developmental biology. However, the development of organoids is limited by the complex composition, batch-to-batch variations, and immunogenicity of basement-membrane matrix in the current culture system, which hinders the clinical translation and in vivo applications of organoids. Hydrogels are highly hydrated 3D polymer network materials, with modifiable mechanical and biochemical properties by engineering, representing an ideal alternative to basement-membrane matrix. This article reviews the research progress in engineered hydrogels with defined composition currently used in organoid culture. We introduce the structural characteristics and engineering design considerations of hydrogels, emphasize the latest research progress and specific application cases, and discuss the future development of these engineered hydrogels, provide valuable insights for the further advancement and optimization of engineered hydrogels for organoid.
Hydrogels/chemistry* ; Organoids/cytology* ; Tissue Engineering/methods* ; Humans ; Animals ; Pluripotent Stem Cells/cytology* ; Cell Culture Techniques, Three Dimensional/methods* ; Tissue Scaffolds

Chronic non-healing wounds significantly impair patient rehabilitation and remain a critical clinical challenge. Stem cell-derived exosomes, owing to their biocompatibility and physiological activity, have emerged as a promising therapeutic approach in regenerative medicine. Beyond their intrinsic wound-healing properties, exosomes are increasingly explored as carriers for small-molecule drugs to enhance synergistic treatment effects. Although microRNAs (miRNAs) exhibit potential in promoting cell proliferation and re-epithelialization, their clinical application is hindered by poor stability. In this study, we investigated the therapeutic effects of miR-132-3p-loaded human umbilical mesenchymal stem cell-derived exosomes (miR-132-3p@UMSC-EXOs) on human foreskin fibroblast-1 (HFF-1). Our findings demonstrated that miR-132-3p@UMSC-EXOs significantly enhanced proliferation and migration of HFF-1, while reducing intracellular reactive oxygen species (ROS) levels compared with unloaded exosomes. Furthermore, qRT-PCR and Western blotting analyses revealed that miR-132-3p@UMSC-EXOs modulated the expression of genes associated with extracellular matrix (ECM) remodeling and inflammation, suggesting their potential to upregulate collagen synthesis and improve ECM metabolism. These results highlight the therapeutic promise of miR-132-3p@UMSC-EXOs in accelerating wound healing.
Humans ; MicroRNAs/pharmacology* ; Exosomes/metabolism* ; Mesenchymal Stem Cells/cytology* ; Wound Healing ; Umbilical Cord/cytology* ; Cell Proliferation ; Fibroblasts/cytology* ; Skin/injuries* ; Cell Movement ; Reactive Oxygen Species/metabolism* ; Cells, Cultured

Objective To investigate the effects of folate deficiency on changes in histone H3 lysine 4 (H3K4) mono-methylation (me1)-marked enhancers and the molecular mechanism underpinning the folate deficiency-induced neural tube defects (NTD). Methods Mouse embryonic stem cells (mESCs) were cultured in the folate-free DMEM medium (folate-deficient group) and the DMEM medium containing 4 mg/L folate (normal control group),respectively.Chromatin immunoprecipitation sequencing (ChIP-seq) was performed for H3K4me1. The mouse model of folate-induced NTD was established,and transcriptome sequencing (RNA-seq) was performed for the brain tissue of fetal mice to reveal the differential expression profiles.The results were validated through real-time quantitative polymerase chain reaction (RT-qPCR).The activity of the differential peak regions of H3K4me1 was verified through the luciferase reporter assay. Results The folate content in the mESCs cultured in the folate-free medium reduced compared with that in the normal control group (P=0.008).The H3K4me1-maked enhancers in the mESCs cultured in the folate-free medium induced significant changes in intronic regions,and these changes were concentrated in metabolic and energy metabolism processes (q=9.56×10^-48,P=1.28×10^-47).The differentially expressed genes harboring H3K4me1-marked enhancers in mESCs were mainly enriched in the Wnt signaling pathway (q=0.004,P=0.004 7).ChIP-qPCR results confirmed that H3K4me1 binding decreased in the differential peak regions of the Ldlrap1 gene (P=0.008),Camta1 gene (P=0.002),and Apc2 gene (P=0.012).The H3K4 demethylase inhibitor T-448 effectively reversed the H3K4me1 binding in the differential peak regions of the aforementioned genes (P=0.01).The results of RNA-seq for the brain tissue of NTD fetal mice showed significant enrichment of the differentially expressed genes in the Wnt signaling pathway (P=1.52×10^-5).The enrichment of differential peak regions of H3K4me1-marked enhancers in Apc2,Ldlrap1,and Camta1 genes in the brain tissue also showed significant changes.The differential peak region in Apc2 exhibited transcription factor activity (P=0.020). Conclusion Folate deficiency may affect changes in H3K4me1-marked enhancers to participate in the regulation of neural tube closure genes,thereby inducing the occurrence of NTD.
Neural Tube Defects/genetics* ; Animals ; Mice ; Folic Acid Deficiency/complications* ; Histones/metabolism* ; Folic Acid/metabolism* ; Methylation ; Mouse Embryonic Stem Cells/metabolism* ; Wnt Signaling Pathway ; Lysine/metabolism* ; Chromatin Immunoprecipitation Sequencing

This study aims to elucidate the role and mechanism of clematichinenoside AR(CAR) in protecting bone marrow mesenchymal stem cells(BMSCs) from hypoxia-induced apoptosis. BMSCs were isolated by the bone fragment method and identified by flow cytometry. Cells were cultured under normal conditions(37℃, 5% CO_2) and hypoxic conditions(37℃, 90% N_2, 5% CO_2) and treated with CAR. The BMSCs were classified into eight groups: control(normal conditions), CAR(normal conditions + CAR), hypoxia 24 h, hypoxia 24 h + CAR, hypoxia 48 h, hypoxia 48 h + CAR, hypoxia 72 h, and hypoxia 72 h + CAR. The cell counting kit-8(CCK-8) assay and terminal-deoxynucleoitidyl transferase mediated nick end labeling(TUNEL) were employed to measure cell proliferation and apoptosis, respectively. The number of mitochondria and mitochondrial membrane potential were measured by MitoTracker®Red CM-H2XRo staining and JC-1 staining, respectively. The level of reactive oxygen species(ROS) was measured with the DCFH-DA fluorescence probe. The protein levels of B-cell lymphoma-2 associated X protein(BAX), caspase-3, and optic atrophy 1(OPA1) were determined by Western blot. The results demonstrated that CAR significantly increased cell proliferation. Compared with the control group, the hypoxia groups showed increased apoptosis rates, reduced mitochondria, elevated ROS levels, decreased mitochondrial membrane potential, upregulated expression of BAX and caspase-3, and downregulated expression of OPA1. In comparison to the corresponding hypoxia groups, CAR intervention significantly decreased the apoptosis rate, increased mitochondria, reduced ROS levels, elevated mitochondrial membrane potential, downregulated the expression of BAX and caspase-3, and upregulated the expression of OPA1. Therefore, it can be concluded that CAR may exert an anti-apoptotic effect on BMSCs under hypoxic conditions by regulating OPA1 to maintain mitochondrial homeostasis.
Mesenchymal Stem Cells/metabolism* ; Apoptosis/drug effects* ; Mitochondria/metabolism* ; Animals ; Rats ; Cell Hypoxia/drug effects* ; Homeostasis/drug effects* ; Reactive Oxygen Species/metabolism* ; Rats, Sprague-Dawley ; Membrane Potential, Mitochondrial/drug effects* ; Saponins/pharmacology* ; Caspase 3/genetics* ; Male ; bcl-2-Associated X Protein/genetics* ; Bone Marrow Cells/metabolism* ; Cell Proliferation/drug effects* ; Protective Agents/pharmacology* ; Cells, Cultured

This study aims to investigate the pharmacological effects and mechanisms of Yougui Yin in treating glucocorticoid-induced osteonecrosis. A rat model of glucocorticoid-associated osteonecrosis of the femoral head(GA-ONFH) was established by intramuscular injection of dexamethasone at 20 mg·kg~(-1) every other day for 8 weeks. Rats were randomly allocated into control, model, and low-and high-dose(1.5 and 3.0 g·kg~(-1), respectively) Yougui Yin groups. After modeling, rats in Yougui Yin groups were administrated with Yougui Yin via gavage, which was followed by femoral specimen collection. Hematoxylin-eosin staining was employed to observe femoral head repair, and immunofluorescence was employed to assess adipogenic differentiation of bone marrow mesenchymal stem cells(BMSCs) within the femoral head. Cell experiments were carried out with dexamethasone(1 μmol·L~(-1))-treated BMSCs to evaluate the effects of Yougui Yin-medicated serum on adipogenic differentiation. Animal experiments demonstrated that compared with the model group, Yougui Yin at both high and low doses significantly improved bone mineral density(BMD), bone volume/total volume(BV/TV) ratio, and trabecular thickness(Tb.Th) in the femoral head. Additionally, Yougui Yin alleviated necrosis-like changes and adipocyte infiltration and significantly reduced the expression level of peroxisome proliferator-activated receptor γ(PPARγ) in the femoral head, thereby suppressing the adipogenic differentiation of BMSCs in GA-ONFH rats. The cell experiments revealed that Yougui Yin-medicated serum markedly inhibited dexamethasone-induced adipogenic differentiation of BMSCs and down-regulated the level of PPARγ. The overexpression of PPARγ attenuated the inhibitory effect of Yougui Yin-medicated serum on the adipogenic differentiation of BMSCs, indicating the critical role of PPARγ in Yougui Yin-mediated suppression of adipogenic differentiation of BMSCs. In conclusion, Yougui Yin exerts therapeutic effects on glucocorticoid-induced osteonecrosis by down-regulating PPARγ expression and inhibiting adipogenic differentiation of BMSCs.
Animals ; Mesenchymal Stem Cells/metabolism* ; PPAR gamma/genetics* ; Rats ; Drugs, Chinese Herbal/administration & dosage* ; Male ; Glucocorticoids/adverse effects* ; Rats, Sprague-Dawley ; Adipogenesis/drug effects* ; Osteonecrosis/genetics* ; Cell Differentiation/drug effects* ; Bone Marrow Cells/metabolism* ; Femur Head Necrosis/chemically induced* ; Humans

OBJECTIVE: To investigate the effects of sodium valproate (VPA) in inhibiting Erastin-induced ferroptosis in bone marrow mesenchymal stem cells (BMSCs) and its underlying mechanisms. METHODS: BMSCs were isolated from bone marrow of 8-week-old Spragur Dawley rats and identified [cell surface antigens CD90, CD44, and CD45 were analyzed by flow cytometry, and osteogenic and adipogenic differentiation abilities were assessed by alizarin red S (ARS) and oil red O staining, respectively]. Cells of passage 3 were used for the Erastin-induced ferroptosis model, with different concentrations of VPA for intervention. The optimal drug concentration was determined using the cell counting kit 8 assay. The experiment was divided into 4 groups: group A, cells were cultured in osteogenic induction medium for 24 hours; group B, cells were cultured in osteogenic induction medium containing optimal concentration Erastin for 24 hours; group C, cells were cultured in osteogenic induction medium containing optimal concentration Erastin and VPA for 24 hours; group D, cells were cultured in osteogenic induction medium containing optimal concentration Erastin and VPA, and 8 μmol/L EX527 for 24 hours. The mitochondrial state of the cells was evaluated, including the levels of malondialdehyde (MDA), glutathione (GSH), and reactive oxygen species (ROS). Osteogenic capacity was assessed by alkaline phosphatase (ALP) activity and ARS staining. Western blot analysis was performed to detect the expressions of osteogenic-related proteins [Runt-related transcription factor 2 (RUNX2) and osteopontin (OPN)], ferroptosis-related proteins [glutathione peroxidase 4 (GPX4), ferritin heavy chain 1 (FTH1), and solute carrier family 7 member 11 (SLC7A11)], and pathway-related proteins [adenosine monophosphate-activated protein kinase (AMPK) and Sirtuin 1 (SIRT1)]. RESULTS: The cultured cells were identified as BMSCs. VPA inhibited Erastin-induced ferroptosis and the decline of osteogenic ability in BMSCs, acting through the activation of the AMPK/SIRT1 pathway. VPA significantly reduced the levels of ROS and MDA in Erastin-treated BMSCs and significantly increased GSH levels. Additionally, the expression levels of ferroptosis-related proteins (GPX4, FTH1, and SLC7A11) significantly decreased. VPA also upregulated the expressions of osteogenic-related proteins (RUNX2 and OPN), enhanced mineralization and osteogenic differentiation, and increased the expressions of pathway-related proteins (AMPK and SIRT1). These effects could be reversed by the SIRT1 inhibitor EX527. CONCLUSION VPA inhibits ferroptosis in BMSCs through the AMPK/SIRT1 axis and promotes osteogenesis.
Mesenchymal Stem Cells/metabolism* ; Ferroptosis/drug effects* ; Animals ; Valproic Acid/pharmacology* ; Rats ; Rats, Sprague-Dawley ; Sirtuin 1/metabolism* ; Cell Differentiation/drug effects* ; Cells, Cultured ; AMP-Activated Protein Kinases/metabolism* ; Osteogenesis/drug effects* ; Piperazines/pharmacology* ; Bone Marrow Cells/cytology* ; Reactive Oxygen Species/metabolism* ; Signal Transduction/drug effects*

OBJECTIVE: To investigate the effectiveness and preliminary mechanisms of icariin (ICA) in enhancing the reparative effects of adipose-derived stem cells (ADSCs) on skin radiation damagies in rats. METHODS: Twelve SPF-grade Sprague Dawley rats [body weight (220±10) g] were subjected to a single dose of 10 Gy X-ray irradiation on a 1.5 cm×1.5 cm area of their dorsal skin, with a dose rate of 200 cGy/min to make skin radiation damage model. After successful modelling, the rats were randomly divided into 4 groups ( n=3), and on day 2, the corresponding cells were injected subcutaneously into the irradiated wounds: group A received 0.1 mL of rat ADSCs (1×10 ⁷cells/mL), group B received 0.1 mL of rat ADSCs (1×10 ⁷cells/mL)+1 μmol/L ICA (0.1 mL), group C received 0.1 mL of rat ADSCs (1×10 ⁷cells/mL) pretreated with a hypoxia-inducible factor 2α (HIF-2α) inhibitor+1 μmol/L ICA (0.1 mL), and group D received 0.1 mL of rat ADSCs (1×10 ⁷cells/mL) pretreated with a Notch1 inhibitor+1 μmol/L ICA (0.1 mL). All treatments were administered as single doses. The skin injury in the irradiated areas of the rats was observed continuously from day 1 to day 7 after modelling. On day 28, the rats were sacrificed, and skin tissues from the irradiated areas were harvested for histological examination (HE staining and Masson staining) to assess the repair status and for quantitative collagen content detection. Immunohistochemical staining was performed to detect CD31 expression, while Western blot and real-time fluorescence quantitative PCR (qRT-PCR) were used to measure the protein and mRNA relative expression levels of vascular endothelial growth factor (VEGF), platelet-derived growth factor BB (PDGF-BB), fibroblast growth factor 2 (FGF-2), interleukin 10 (IL-10), transforming growth factor β (TGF-β), HIF-2α, and Notch1, 2, and 3. RESULTS: All groups exhibited skin ulcers and redness after irradiation. On day 3, exudation of tissue fluid was observed in all groups. On day 7, group B showed significantly smaller skin injury areas compared to the other 3 groups. On day 28, histological examination revealed that the epidermis was thickened and the dermal fibers were slightly disordered with occasional inflammatory cell aggregation in group A. In group B, the epidermis appeared more normal, the dermal fibers were more orderly, and there was an increase in new blood vessels without significant inflammatory cell aggregation. In contrast, groups C and D showed significantly increased epidermal thickness, disordered and disrupted dermal fibers. Group B had higher collagen fiber content than the other 3 groups, and group D had lower content than group A, with significant differences ( P<0.05). Immunohistochemical staining showed that group B had significantly higher CD31 expression than the other 3 groups, while groups C and D had lower expression than group A, with significant differences ( P<0.05). Western blot and qRT-PCR results indicated that group B had significantly higher relative expression levels of VEGF, PDGF-BB, FGF-2, IL-10, TGF-β, HIF-2α, and Notch1, 2, and 3 proteins and mRNAs compared to the other 3 groups ( P<0.05). CONCLUSION ICA may enhance the reparative effects of ADSCs on rat skin radiation damage by promoting angiogenesis and reducing inflammatory responses through the HIF-2α-VEGF-Notch signaling pathway.
Animals ; Rats, Sprague-Dawley ; Skin/pathology* ; Rats ; Vascular Endothelial Growth Factor A/genetics* ; Basic Helix-Loop-Helix Transcription Factors/genetics* ; Signal Transduction ; Flavonoids/pharmacology* ; Adipose Tissue/cytology* ; Stem Cells/cytology* ; Receptors, Notch/metabolism* ; Radiation Injuries, Experimental/metabolism* ; Wound Healing/drug effects* ; Male