RESUMO
STUDY DESIGN: Animal studies OBJECTIVES: To evaluate the therapeutic effect of olfactory mucosa mesenchymal stem cell (OM-MSCs) transplantation in mice with spinal cord injury (SCI) and to explore the mechanism by which OM-MSCs inhibit neuroinflammation and improve SCI. SETTING: Xiangya Hospital, Central South University; Affiliated Hospital of Guangdong Medical University. METHODS: Mice (C57BL/6, female, 6-week-old) were randomly divided into sham, SCI, and SCI + OM-MSC groups. The SCI mouse model was generated using Allen's method. OM-MSCs were immediately delivered to the lateral ventricle after SCI using stereotaxic brain injections. One day prior to injury and on days 1, 5, 7, 14, 21, and 28 post-injury, the Basso Mouse Scale and Rivlin inclined plate tests were performed. Inflammation and microglial polarization were evaluated using histological staining, immunofluorescence, and qRT-PCR. RESULTS: OM-MSCs originating from the neuroectoderm have great potential in the management of SCI owing to their immunomodulatory effects. OM-MSCs administration improved motor function, alleviated inflammation, promoted the transformation of the M1 phenotype of microglia into the M2 phenotype, facilitated axonal regeneration, and relieved spinal cord injury in SCI mice. CONCLUSIONS: OM-MSCs reduced the level of inflammation in the spinal cord tissue, protected neurons, and repaired spinal cord injury by regulating the M1/M2 polarization of microglia.
Assuntos
Transplante de Células-Tronco Mesenquimais , Camundongos Endogâmicos C57BL , Microglia , Mucosa Olfatória , Traumatismos da Medula Espinal , Animais , Traumatismos da Medula Espinal/terapia , Traumatismos da Medula Espinal/patologia , Transplante de Células-Tronco Mesenquimais/métodos , Mucosa Olfatória/citologia , Microglia/fisiologia , Camundongos , Feminino , Modelos Animais de Doenças , Células-Tronco Mesenquimais/fisiologia , Recuperação de Função Fisiológica/fisiologia , Polaridade Celular/fisiologiaRESUMO
BACKGROUND: Pulmonary fibrosis (PF) is a progressive fibrosing interstitial pneumonia that leads to respiratory failure and other complications, which is ultimately fatal. Mesenchymal stem cells (MSCs) transplant is a promising strategy to solve this problem, while the procurement of MSCs from the patient for autotransplant remains a challenge. METHODS: Here, we presented olfactory mucosa mesenchymal stem cells (OM-MSCs) from mouse turbinate and determined the preventing efficacy of allotransplant for PF. We demonstrated the antiinflammation and immunomodulatory effects of OM-MSCs. Flow cytometric analysis was used to verify the effect of OM-MSCs on monocyte-derived macrophage populations in the lung. RESULTS: Administration of OM-MSCs reduces inflammation, attenuates the matrix metallopeptidase 13 (MMP13) expression level and restores the bleomycin (BLM)-induced pulmonary fibrosis by assessing the architecture of lung, collagen type I; (COL1A1), actin alpha 2, smooth muscle, aorta (ACTA2/α-SMA) and hydroxyproline. This therapeutic effect of OM-MSCs was related to the increase in the ratio of nonclassical monocytes to proinflammatory monocytes in the lung. CONCLUSIONS: This study suggests that transplant of OM-MSCs represents an effective and safe treatment for PF.
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Células-Tronco Mesenquimais , Fibrose Pulmonar , Humanos , Camundongos , Animais , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/terapia , Fibrose Pulmonar/metabolismo , Inflamação/metabolismo , Células-Tronco Mesenquimais/metabolismo , Imunomodulação , Mucosa Olfatória/metabolismoRESUMO
Endothelial cells (ECs) and bone marrow stromal cells (BMSCs) play crucial roles in supporting hematopoiesis and hematopoietic regeneration. However, whether ECs are a source of BMSCs remains unclear. Here, we evaluate the contribution of endothelial-to-mesenchymal transition to BMSC generation in postnatal mice. Single-cell RNA sequencing identifies ECs expressing BMSC markers Prrx1 and Lepr; however, this could not be validated using Prrx1-Cre and Lepr-Cre transgenic mice. Additionally, only a minority of BMSCs are marked by EC lineage tracing models using Cdh5-rtTA-tetO-Cre or Tek-CreERT2. Moreover, Cdh5+ BMSCs and Tek+ BMSCs show distinct spatial distributions and characteristic mesenchymal markers, suggestive of their origination from different progenitors rather than CDH5+ TEK+ ECs. Furthermore, myeloablation induced by 5-fluorouracil treatment does not increase Cdh5+ BMSCs. Our findings indicate that ECs hardly convert to BMSCs during homeostasis and myeloablation-induced hematopoietic regeneration, highlighting the importance of using appropriate genetic models and conducting careful data interpretation in studies concerning endothelial-to-mesenchymal transition.
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Células Endoteliais , Células-Tronco Mesenquimais , Camundongos , Animais , Medula Óssea , Camundongos TransgênicosRESUMO
BACKGROUND AND AIMS: Refractory epilepsy is also known as drug-resistant epilepsy with limited clinical treatment. Benefitting from its safety and easy availability, olfactory mucosa mesenchymal stem cells (OM-MSCs) are considered a preferable MSC source for clinical application. This study aims to investigate whether OM-MSCs are a promising alternative source for treating refractory epilepsy clinically and uncover the mechanism by OM-MSCs administration on an epileptic mouse model. METHODS: OM-MSCs were isolated from turbinal and characterized by flow cytometry. Autologous human OM-MSCs treatment on a patient was carried out using intrathecal administration. Epileptic mouse model was established by 1 mg/kg scopolamine and 300 mg/kg pilocarpine treatment (intraperitoneal). Stereotaxic microinjection was employed to deliver the mouse OM-MSCs. Mouse electroencephalograph recording was used to investigate the seizures. Brain structure was evaluated by magnetic resonance imaging (MRI). Immunohistochemical and immunofluorescent staining of GFAP, IBA1, MAP2, TUBB3, OLIG2, CD4, CD25, and FOXP3 was carried out to investigate the neural cells and Treg cells. QRT-PCR and ELISA were performed to determine the cytokines (Il1b, Il6, Tnf, Il10) on mRNA and protein level. Y-maze, the object location test, and novel object recognition test were performed to measure the cognitive function. Footprint test, rotarod test, balance beam test, and grip strength test were conducted to evaluate the locomotive function. Von Frey testing was carried out to assess the mechanical allodynia. RESULTS: Many beneficial effects of the OM-MSC treatment on disease status, including seizure type, frequency, severity, duration, and cognitive function, and no apparent adverse effects were observed at the 8-year follow-up case. Brain MRI indicated that autologous OM-MSC treatment alleviated brain atrophy in epilepsy patients. A study in an epileptic mouse model revealed that OM-MSC treatment recruited Treg cells to the brain, inhibited inflammation, rebuilt the neural network, and improved the cognitive, locomotive, and perceptive functions of epileptic mice. CONCLUSIONS: Autologous OM-MSC treatment is efficacious for improving chronic refractory epilepsy, suggesting a future therapeutic candidate for epilepsy. TRIAL REGISTRATION: The study was registered with Chinese Clinical Trial Registry (ChiCTR2200055357).
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Epilepsia Resistente a Medicamentos , Células-Tronco Mesenquimais , Humanos , Animais , Camundongos , Epilepsia Resistente a Medicamentos/terapia , Encéfalo , Redes Neurais de Computação , Modelos Animais de Doenças , Mucosa OlfatóriaRESUMO
Alzheimer's disease (AD) is a common neurodegenerative disease that contributes to 60-70% of dementia in elderly people and is currently incurable. Current treatments only relieve the symptoms of AD and slow its progression. Achieving effective neural regeneration to ameliorate cognitive impairment is a major challenge in the treatment of AD. For the first time, we alleviated symptoms of AD in APPswe/PS1dE9 mice (hereafter referred to as AD mice) by transplantation of olfactory mucosa mesenchymal stem cells (OM-MSCs). Our study demonstrated that OM-MSC transplantation promotes amyloid-ß (Aß) clearance, downregulates the inflammatory response, and increases the M2/M1 ratio; OM-MSCs promote the conversion of BV2 (microglia) from M1 to M2 and also Aß clearance in SH-SY5YAPPswe (AD cell model). OM-MSC-transplanted AD mice show improved cognitive learning and locomotive behavior. Our study suggests that OM-MSC transplantation could alleviate the symptoms of AD and promote Aß clearance through immunomodulation, thus demonstrating the great potential and social value of OM-MSC treatment for AD patients.
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Doença de Alzheimer , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Neuroblastoma , Doenças Neurodegenerativas , Animais , Humanos , Camundongos , Doença de Alzheimer/terapia , Peptídeos beta-Amiloides , Mucosa Olfatória , Modelos Animais de Doenças , Camundongos TransgênicosRESUMO
The etiology of epilepsy remains undefined in two-thirds of patients. Here, we identified a de novo variant of ATP1A2 (c.2426 T > G, p.Leu809Arg), which encodes the α2 subunit of Na+/K+-ATPase, from a family with idiopathic epilepsy. This variant caused epilepsy with hemiplegic migraine in the study patients. We generated the point variant mouse model Atp1a2L809R, which recapitulated the epilepsy observed in the study patients. In Atp1a2L809R/WT mice, convulsions were observed and cognitive and memory function was impaired. This variant affected the potassium binding function of the protein, disabling its ion transport ability, thereby increasing the frequency of nerve impulses. Valproate (VPA) and Carbamazepine (CBZ) have limited therapeutic efficacy in ameliorating the epileptic syndromes of Atp1a2L809R/WT mice. Our work revealed that ATP1A2L809R variants cause a predisposition to epilepsy. Moreover, we provide a point variant mouse model for epilepsy research and drug screening.
Assuntos
Epilepsia , Enxaqueca com Aura , Animais , Modelos Animais de Doenças , Epilepsia/genética , Camundongos , Enxaqueca com Aura/genética , Enxaqueca com Aura/metabolismo , Mutação , ATPase Trocadora de Sódio-Potássio/genética , ATPase Trocadora de Sódio-Potássio/metabolismoRESUMO
Both Alzheimer's disease (AD) and osteoporosis (OP) are common age-associated degenerative diseases and are strongly correlated with clinical epidemiology. However, there is a lack of clear pathological relationship between the brain and bone in the current understanding. Here, it is found that young osteocyte, the most abundant cells in bone, secretes extracellular vesicles (OCYYoung -EVs) to ameliorate cognitive impairment and the pathogenesis of AD in APP/PS1 mice and model cells. These benefits of OCYYoung -EVs are diminished in aged osteocyte-derived EVs (OCYAged -EVs). Based on the self-constructed OCY-EVs tracer transgenic mouse models and the in vivo fluorescent imaging system, OCY-EVs have been observed to be transported to the brain under physiological and pathological conditions. In the hippocampal administration of Aß40 induced young AD model mice, the intramedullary injection of Rab27a-shRNA adenovirus inhibits OCYYoung -EVs secretion from bone and aggravates cognitive impairment. Proteomic quantitative analysis reveals that OCYYoung -EVs, compared to OCYAged -EVs, enrich multiple protective factors of AD pathway. The study uncovers the role of OCY-EV as a regulator of brain health, suggesting a novel mechanism in bone-brain communication.
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Doença de Alzheimer , Vesículas Extracelulares , Envelhecimento , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Vesículas Extracelulares/metabolismo , Camundongos , Osteócitos/metabolismo , ProteômicaRESUMO
Fracture healing is a complicated process affected by many factors, such as inflammatory responses and angiogenesis. Omentin-1 is an adipokine with anti-inflammatory properties, but whether omentin-1 affects the fracture healing process is still unknown. Here, by using global omentin-1 knockout (omentin-1-/-) mice, we demonstrated that omentin-1 deficiency resulted in delayed fracture healing in mice, accompanied by increased inflammation and osteoclast formation, and decreased production of platelet-derived growth factor-BB (PDGF-BB) and osteogenesis-promoting vessels that are strongly positive for CD31 and Endomucin (CD31hiEmcnhi) in the fracture area. In vitro, omentin-1 treatment suppressed the ability of the tumor necrosis factor-α (TNF-α)-activated macrophages to stimulate multi-nuclear osteoclast formation, resulting in a significant increase in the generation of mono-nuclear preosteoclasts and PDGF-BB, a pro-angiogenic protein that is abundantly secreted by preosteoclasts. PDGF-BB significantly augmented endothelial cell proliferation, tube formation and migration, whereas direct treatment with omentin-1 did not induce obvious effects on angiogenesis activities of endothelial cells. Our study suggests a positive role of omentin-1 in fracture healing, which may be associated with the inhibition of inflammation and stimulation of preosteoclast PDGF-BB-mediated promotion of CD31hiEmcnhi vessel formation.
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Citocinas/genética , Fraturas do Fêmur/genética , Consolidação da Fratura , Proteínas Ligadas por GPI/genética , Lectinas/genética , Sialoglicoproteínas/metabolismo , Animais , Movimento Celular , Modelos Animais de Doenças , Feminino , Fraturas do Fêmur/etiologia , Fraturas do Fêmur/imunologia , Técnicas de Inativação de Genes , Camundongos , Osteoclastos/metabolismo , Osteogênese , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Células RAW 264.7 , Microtomografia por Raio-XRESUMO
Alzheimer's disease (AD) is currently ranked as the third leading cause of death for eldly people, just behind heart disease and cancer. Autophagy is declined with aging. Our study determined the biphasic changes of miR-331-3p and miR-9-5p associated with AD progression in APPswe/PS1dE9 mouse model and demonstrated inhibiting miR-331-3p and miR-9-5p treatment prevented AD progression by promoting the autophagic clearance of amyloid beta (Aß). Methods: The biphasic changes of microRNAs were obtained from RNA-seq data and verified by qRT-PCR in early-stage (6 months) and late-stage (12 months) APPswe/PS1dE9 mice (hereinafter referred to as AD mice). The AD progression was determined by analyzing Aß levels, neuron numbers (MAP2+) and activated microglia (CD68+IBA1+) in brain tissues using immunohistological and immunofluorescent staining. MRNA and protein levels of autophagic-associated genes (Becn1, Sqstm1, LC3b) were tested to determine the autophagic activity. Morris water maze and object location test were employed to evaluate the memory and learning after antagomirs treatments in AD mice and the Aß in the brain tissues were determined. Results: MiR-331-3p and miR-9-5p are down-regulated in early-stage of AD mice, whereas up-regulated in late-stage of AD mice. We demonstrated that miR-331-3p and miR-9-5p target autophagy receptors Sequestosome 1 (Sqstm1) and Optineurin (Optn), respectively. Overexpression of miR-331-3p and miR-9-5p in SH-SY5Y cell line impaired autophagic activity and promoted amyloid plaques formation. Moreover, AD mice had enhanced Aß clearance, improved cognition and mobility when treated with miR-331-3p and miR-9-5p antagomirs at late-stage. Conclusion: Our study suggests that using miR-331-3p and miR-9-5p, along with autophagic activity and amyloid plaques may distinguish early versus late stage of AD for more accurate and timely diagnosis. Additionally, we further provide a possible new therapeutic strategy for AD patients by inhibiting miR-331-3p and miR-9-5p and enhancing autophagy.
Assuntos
Doença de Alzheimer/prevenção & controle , Autofagia , Modelos Animais de Doenças , Regulação da Expressão Gênica , MicroRNAs/antagonistas & inibidores , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Animais , Humanos , Masculino , Camundongos , Camundongos Transgênicos , MicroRNAs/genética , Neurônios/metabolismo , Neurônios/patologiaRESUMO
Senile osteoporosis (OP) is often concomitant with decreased autophagic activity. OPTN (optineurin), a macroautophagy/autophagy (hereinafter referred to as autophagy) receptor, is found to play a pivotal role in selective autophagy, coupling autophagy with bone metabolism. However, its role in osteogenesis is still mysterious. Herein, we identified Optn as a critical molecule of cell fate decision for bone marrow mesenchymal stem cells (MSCs), whose expression decreased in aged mice. Aged mice revealed osteoporotic bone loss, elevated senescence of MSCs, decreased osteogenesis, and enhanced adipogenesis, as well as optn-/ - mice. Importantly, restoring Optn by transplanting wild-type MSCs to optn-/ - mice or infecting optn-/ - mice with Optn-containing lentivirus rescued bone loss. The introduction of a loss-of-function mutant of OptnK193R failed to reestablish a bone-fat balance. We further identified FABP3 (fatty acid binding protein 3, muscle and heart) as a novel selective autophagy substrate of OPTN. FABP3 promoted adipogenesis and inhibited osteogenesis of MSCs. Knockdown of FABP3 alleviated bone loss in optn-/ - mice and aged mice. Our study revealed that reduced OPTN expression during aging might lead to OP due to a lack of FABP3 degradation via selective autophagy. FABP3 accumulation impaired osteogenesis of MSCs, leading to the occurrence of OP. Thus, reactivating OPTN or inhibiting FABP3 would open a new avenue to treat senile OP.Abbreviations: ADIPOQ: adiponectin, C1Q and collagen domain containing; ALPL: alkaline phosphatase, liver/bone/kidney; BGLAP/OC/osteocalcin: bone gamma carboxyglutamate protein; BFR/BS: bone formation rate/bone surface; CALCOCO2/NDP52: calcium binding and coiled-coil domain 2; CDKN1A/p21: cyclin-dependent kinase inhibitor 1A; CDKN2A/p16: cyclin dependent kinase inhibitor 2A; CDKN2B/p15: cyclin dependent kinase inhibitor 2B; CEBPA: CCAAT/enhancer binding protein (C/EBP), alpha; COL1A1: collagen, type I, alpha 1; Ct. BV/TV: cortical bone volume fraction; Ct. Th: cortical thickness; Es. Pm: endocortical perimeter; FABP4/Ap2: fatty acid binding protein 4, adipocyte; H2AX: H2A.X variant histone; HE: hematoxylin and eosin; MAP1LC3B: microtubule-associated protein 1 light chain 3 beta; MAR: mineral apposition rate; MSCs: bone marrow mesenchymal stem cells; NBR1: NBR1, autophagy cargo receptor; OP: osteoporosis; OPTN: optineurin; PDB: Paget disease of bone; PPARG: peroxisome proliferator activated receptor gamma; Ps. Pm: periosteal perimeter; qRT-PCR: quantitative real-time PCR; γH2AX: Phosphorylation of the Serine residue of H2AX; ROS: reactive oxygen species; RUNX2: runt related transcription factor 2; SA-GLB1: senescence-associated (SA)-GLB1 (galactosidase, beta 1); SP7/Osx/Osterix: Sp7 transcription factor 7; SQSTM1/p62: sequestosome 1; TAX1BP1: Tax1 (human T cell leukemia virus type I) binding protein 1; Tb. BV/TV: trabecular bone volume fraction; Tb. N: trabecular number; Tb. Sp: trabecular separation; Tb. Th: trabecular thickness; µCT: micro computed tomography.
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Envelhecimento , Autofagia , Proteínas de Ciclo Celular , Proteína 3 Ligante de Ácido Graxo , Proteínas de Membrana Transportadoras , Células-Tronco Mesenquimais , Adipogenia , Animais , Proteínas de Ciclo Celular/metabolismo , Diferenciação Celular , Proteína 3 Ligante de Ácido Graxo/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Osteogênese , Osteoporose , Microtomografia por Raio-XRESUMO
Osteosarcoma is a common malignant bone cancer easily to metastasize. Much safer and more efficient strategies are still needed to suppress osteosarcoma growth and lung metastasis. We recently presented a pure physical method to fabricate Ångstrom-scale silver particles (AgÅPs) and determined the anti-tumor efficacy of fructose-coated AgÅPs (F-AgÅPs) against lung and pancreatic cancer. Our study utilized an optimized method to obtain smaller F-AgÅPs and aimed to assess whether F-AgÅPs can be used as an efficient and safe agent for osteosarcoma therapy. We also investigated whether the induction of apoptosis by altering glucose metabolic phenotype contributes to the F-AgÅPs-induced anti-osteosarcoma effects. Methods: A modified method was developed to prepare smaller F-AgÅPs. The anti-tumor, anti-metastatic and pro-survival efficacy of F-AgÅPs and their toxicities on healthy tissues were compared with that of cisplatin (a first-line chemotherapeutic drug for osteosarcoma therapy) in subcutaneous or orthotopic osteosarcoma-bearing nude mice. The pharmacokinetics, biodistribution and excretion of F-AgÅPs were evaluated by testing the levels of silver in serum, tissues, urine and feces of mice. A series of assays in vitro were conducted to assess whether the induction of apoptosis mediates the killing effects of F-AgÅPs on osteosarcoma cells and whether the alteration of glucose metabolic phenotype contributes to F-AgÅPs-induced apoptosis. Results: The newly obtained F-AgÅPs (9.38 ± 4.11 nm) had good stability in different biological media or aqueous solutions and were more effective than cisplatin in inhibiting tumor growth, improving survival, attenuating osteolysis and preventing lung metastasis in osteosarcoma-bearing nude mice after intravenous injection, but were well tolerated in normal tissues. One week after injection, about 68% of F-AgÅPs were excreted through feces. F-AgÅPs induced reactive oxygen species (ROS)-dependent apoptosis of osteosarcoma cells but not normal cells, owing to their ability to selectively shift glucose metabolism of osteosarcoma cells from glycolysis to mitochondrial oxidation by inhibiting pyruvate dehydrogenase kinase (PDK). Conclusion: Our study suggests the promising prospect of F-AgÅPs as a powerful selective anticancer agent for osteosarcoma therapy.
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Neoplasias Ósseas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas Metálicas/administração & dosagem , Osteossarcoma/tratamento farmacológico , Prata/administração & dosagem , Adolescente , Animais , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/administração & dosagem , Feminino , Frutose/química , Humanos , Lactente , Recém-Nascido , Injeções Intravenosas , Neoplasias Pulmonares/secundário , Masculino , Nanopartículas Metálicas/química , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Osteossarcoma/secundário , Oxirredução/efeitos dos fármacos , Cultura Primária de Células , Piruvato Desidrogenase Quinase de Transferência de Acetil/antagonistas & inibidores , Piruvato Desidrogenase Quinase de Transferência de Acetil/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Eliminação Renal , Transdução de Sinais/efeitos dos fármacos , Prata/farmacocinética , Prata/urina , Distribuição Tecidual , Efeito Warburg em Oncologia/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto JovemRESUMO
Osteonecrosis of the femoral head (ONFH) frequently occurs after glucocorticoid (GC) treatment. Extracellular vesicles (EVs) are important nano-sized paracrine mediators of intercellular crosstalk. This study aimed to determine whether EVs from human urine-derived stem cells (USC-EVs) could protect against GC-induced ONFH and focused on the impacts of USC-EVs on angiogenesis and apoptosis to explore the mechanism by which USC-EVs attenuated GC-induced ONFH. The results in vivo showed that the intravenous administration of USC-EVs at the early stage of GC exposure could rescue angiogenesis impairment, reduce apoptosis of trabecular bone and marrow cells, prevent trabecular bone destruction and improve bone microarchitecture in the femoral heads of rats. In vitro, USC-EVs reversed the GC-induced suppression of endothelial angiogenesis and activation of apoptosis. Deleted in malignant brain tumors 1 (DMBT1) and tissue inhibitor of metalloproteinases 1 (TIMP1) proteins were enriched in USC-EVs and essential for the USC-EVs-induced pro-angiogenic and anti-apoptotic effects in GC-treated cells, respectively. Knockdown of TIMP1 attenuated the protective effects of USC-EVs against GC-induced ONFH. Our study suggests that USC-EVs are a promising nano-sized agent for the prevention of GC-induced ONFH by delivering pro-angiogenic DMBT1 and anti-apoptotic TIMP1. STATEMENT OF SIGNIFICANCE: This study demonstrates that the intravenous injection of extracellular vesicles from human urine-derived stem cells (USC-EVs) at the early stage of glucocorticoid (GC) exposure efficiently protects the rats from the GC-induced osteonecrosis of the femoral head (ONFH). Moreover, this study identifies that the promotion of angiogenesis and inhibition of apoptosis by transferring pro-angiogenic DMBT1 and anti-apoptotic TIMP1 proteins contribute importantly to the USC-EVs-induced protective effects against GC-induced ONFH. This study suggests the promising prospect of USC-EVs as a new nano-sized agent for protecting against GC-induced ONFH, and the potential of DMBT1 and TIMP1 as the molecular targets for further augmenting the protective function of USC-EVs.