Epilepsy is a serious neurological disorder;however,the effectiveness of current medications is often suboptimal.Recently,stem cell technology has demonstrated remarkable therapeutic potential in addressing various ne...Epilepsy is a serious neurological disorder;however,the effectiveness of current medications is often suboptimal.Recently,stem cell technology has demonstrated remarkable therapeutic potential in addressing various neurological diseases,igniting interest in its applicability for epilepsy treatment.This comprehensive review summarizes different therapeutic approaches utilizing various types of stem cells.Preclinical experiments have explored the use and potential therapeutic effects of mesenchymal stem cells,including genetically modified variants.Clinical trials involving patientderived mesenchymal stem cells have shown promising results,with reductions in the frequency of epileptic seizures and improvements in neurological,cognitive,and motor functions reported.Another promising therapeutic strategy involves neural stem cells.These cells can be cultured outside the body and directed to differentiate into specific cell types.The transplant of neural stem cells has the potential to replace lost inhibitory interneurons,providing a novel treatment avenue for epilepsy.Embryonic stem cells are characterized by their significant capacity for self-renewal and their ability to differentiate into any type of somatic cell.In epilepsy treatment,embryonic stem cells can serve three primary functions:neuron regeneration,the maintenance of cellular homeostasis,and restorative activity.One notable strategy involves differentiating embryonic stem cells intoγ-aminobutyric acidergic neurons for transplantation into lesion sites.This approach is currently undergoing clinical trials and could be a breakthrough in the treatment of refractory epilepsy.Induced pluripotent stem cells share the same genetic background as the donor,thereby reducing the risk of immune rejection and addressing ethical concerns.However,research on induced pluripotent stem cell therapy remains in the preclinical stage.Despite the promise of stem cell therapies for epilepsy,several limitations must be addressed.Safety concerns persist,including issues such as tumor formation,and the low survival rate of transplanted cells remains a significant challenge.Additionally,the high cost of these treatments may be prohibitive for some patients.In summary,stem cell therapy shows considerable promise in managing epilepsy,but further research is needed to overcome its existing limitations and enhance its clinical applicability.展开更多
Ischemic stroke is a significant global health crisis,frequently resulting in disability or death,with limited therapeutic interventions available.Although various intrinsic reparative processes are initiated within t...Ischemic stroke is a significant global health crisis,frequently resulting in disability or death,with limited therapeutic interventions available.Although various intrinsic reparative processes are initiated within the ischemic brain,these mechanisms are often insufficient to restore neuronal functionality.This has led to intensive investigation into the use of exogenous stem cells as a potential therapeutic option.This comprehensive review outlines the ontogeny and mechanisms of activation of endogenous neural stem cells within the adult brain following ischemic events,with focus on the impact of stem cell-based therapies on neural stem cells.Exogenous stem cells have been shown to enhance the proliferation of endogenous neural stem cells via direct cell-tocell contact and through the secretion of growth factors and exosomes.Additionally,implanted stem cells may recruit host stem cells from their niches to the infarct area by establishing so-called“biobridges.”Furthermore,xenogeneic and allogeneic stem cells can modify the microenvironment of the infarcted brain tissue through immunomodulatory and angiogenic effects,thereby supporting endogenous neuroregeneration.Given the convergence of regulatory pathways between exogenous and endogenous stem cells and the necessity for a supportive microenvironment,we discuss three strategies to simultaneously enhance the therapeutic efficacy of both cell types.These approaches include:(1)co-administration of various growth factors and pharmacological agents alongside stem cell transplantation to reduce stem cell apoptosis;(2)synergistic administration of stem cells and their exosomes to amplify paracrine effects;and(3)integration of stem cells within hydrogels,which provide a protective scaffold for the implanted cells while facilitating the regeneration of neural tissue and the reconstitution of neural circuits.This comprehensive review highlights the interactions and shared regulatory mechanisms between endogenous neural stem cells and exogenously implanted stem cells and may offer new insights for improving the efficacy of stem cell-based therapies in the treatment of ischemic stroke.展开更多
Our previous study demonstrated that combined transplantation of bone marrow mesenchymal stem cells and retinal progenitor cells in rats has therapeutic effects on retinal degeneration that are superior to transplanta...Our previous study demonstrated that combined transplantation of bone marrow mesenchymal stem cells and retinal progenitor cells in rats has therapeutic effects on retinal degeneration that are superior to transplantation of retinal progenitor cells alone.Bone marrow mesenchymal stem cells regulate and interact with various cells in the retinal microenvironment by secreting neurotrophic factors and extracellular vesicles.Small extracellular vesicles derived from bone marrow mesenchymal stem cells,which offer low immunogenicity,minimal tumorigenic risk,and ease of transportation,have been utilized in the treatment of various neurological diseases.These vesicles exhibit various activities,including anti-inflammatory actions,promotion of tissue repair,and immune regulation.Therefore,novel strategies using human retinal progenitor cells combined with bone marrow mesenchymal stem cell-derived small extracellular vesicles may represent an innovation in stem cell therapy for retinal degeneration.In this study,we developed such an approach utilizing retinal progenitor cells combined with bone marrow mesenchymal stem cell-derived small extracellular vesicles to treat retinal degeneration in Royal College of Surgeons rats,a genetic model of retinal degeneration.Our findings revealed that the combination of bone marrow mesenchymal stem cell-derived small extracellular vesicles and retinal progenitor cells significantly improved visual function in these rats.The addition of bone marrow mesenchymal stem cell-derived small extracellular vesicles as adjuvants to stem cell transplantation with retinal progenitor cells enhanced the survival,migration,and differentiation of the exogenous retinal progenitor cells.Concurrently,these small extracellular vesicles inhibited the activation of regional microglia,promoted the migration of transplanted retinal progenitor cells to the inner nuclear layer of the retina,and facilitated their differentiation into photoreceptors and bipolar cells.These findings suggest that bone marrow mesenchymal stem cell-derived small extracellular vesicles potentiate the therapeutic efficacy of retinal progenitor cells in retinal degeneration by promoting their survival and differentiation.展开更多
The adult subventricular zone of the lateral ventricles and the subgranular zone in the hippocampal dentate gyrus(DG)are the two brain regions where neurogenesis occurs throughout life in the adult mammalian brain(Min...The adult subventricular zone of the lateral ventricles and the subgranular zone in the hippocampal dentate gyrus(DG)are the two brain regions where neurogenesis occurs throughout life in the adult mammalian brain(Ming and Song,2011).Adult quiescent hippocampal neural stem cells(NSCs)are bona fide stem cells and,when activated,give rise to newborn granule neurons in the adult brain,which play vital roles in learning,memory,mood,and affective cognition(Bonaguidi et al.,2011;Ming and Song,2011).展开更多
Bone regeneration for non-load-bearing defects remains a significant clinical challenge requiring advanced biomaterials and cellular strategies.Adiposederived mesenchymal stem cells(AD-MSCs)have garnered significant i...Bone regeneration for non-load-bearing defects remains a significant clinical challenge requiring advanced biomaterials and cellular strategies.Adiposederived mesenchymal stem cells(AD-MSCs)have garnered significant interest in bone tissue engineering(BTE)because of their abundant availability,minimally invasive harvesting procedures,and robust differentiation potential into osteogenic lineages.Unlike bone marrow-derived mesenchymal stem cells,AD-MSCs can be easily obtained in large quantities,making them appealing alternatives for therapeutic applications.This review explores hydrogels containing polymers,such as chitosan,collagen,gelatin,and hyaluronic acid,and their composites,tailored for BTE,and emphasizes the importance of these hydrogels as scaffolds for the delivery of AD-MSCs.Various hydrogel fabrication techniques and biocompatibility assessments are discussed,along with innovative modifications to enhance osteogenesis.This review also briefly outlines AD-MSC isolation methods and advanced embedding techniques for precise cell placement,such as direct encapsulation and three-dimensional bioprinting.We discuss the mechanisms of bone regeneration in the AD-MSC-laden hydrogels,including osteoinduction,vascularization,and extracellular matrix remodeling.We also review the preclinical and clinical applications of AD-MSC-hydrogel systems,emphasizing their success and limitations.In this review,we provide a comprehensive overview of AD-MSC-based hydrogel systems to guide the development of effective therapies for bone regeneration.展开更多
Hepatocellular carcinoma(HCC)is a pressing global health problem and is the sixth most common cancer and the third leading cause of cancer mortality worldwide.Despite continuous advances in treatment modalities,the 5-...Hepatocellular carcinoma(HCC)is a pressing global health problem and is the sixth most common cancer and the third leading cause of cancer mortality worldwide.Despite continuous advances in treatment modalities,the 5-year survival rate is low with a high propensity for recurrence and metastasis1.This clinical challenge in treating HCC is largely attributed to the heterogeneity and intrinsic therapy resistance of cancer stem cells(CSCs),which are a subpopulation of cells with self-renewal capability and multidirectional differentiation potential to induce tumorigenicity2.The behavior and maintenance of CSCs are not autonomous but critically dependent on the complex bidirectional crosstalk between CSCs and the tumor immune microenvironment(TIME)1.In this review we first summarize the recent progress in characterizing CSCs and the interactions between CSCs and the TIME in HCC.Next,we discuss the emerging therapeutic strategies targeting CSC populations with the ongoing challenges.Finally,we give our perspectives on the future directions in HCC CSC research.展开更多
A recently published prospective study marks a breakthrough for congenital olfactory disorders in children.The study provides the first long-term,three-year follow-up data,robustly demonstrating the durable efficacy a...A recently published prospective study marks a breakthrough for congenital olfactory disorders in children.The study provides the first long-term,three-year follow-up data,robustly demonstrating the durable efficacy and safety of autologous nasal epithelial stem cell transplantation.This work reveals immense therapeutic potential for a condition traditionally considered untreatable.However,this milestone achievement also presents new challenges.To translate this pioneering therapy from a single-center success to a global standard,multicenter,controlled clinical trials must be initiated immediately.Only through rigorous validation can we ensure its widespread adoption and ultimately bring hope to millions of children worldwide.展开更多
BACKGROUND The incidence of diabetic atherosclerosis(DMA)is increasing worldwide,but its pathogenesis remains incompletely understood.In addition to cardiovascular complications,bladder dysfunction is one of the commo...BACKGROUND The incidence of diabetic atherosclerosis(DMA)is increasing worldwide,but its pathogenesis remains incompletely understood.In addition to cardiovascular complications,bladder dysfunction is one of the common comorbidities associated with DMA but is often refractory to current treatments.AIM To investigate the therapeutic effect of human amniotic fluid stem cell-derived extracellular vesicles(hAFSC-EVs)on the recovery of bladder dysfunction in DMA rats.METHODS Eighty rats were divided into normal control,streptozotocin-induced diabetic rats,diabetic rats subjected to arterial balloon endothelial injury of common iliac artery(DMA),and DMA rats treated with hAFSC-EVs(DMA+hAFSC-EVs).At 4 weeks and 12 weeks after DMA induction,levels of blood glucose,total cholesterol,triglyceride,high-density lipoprotein cholesterol,low-density lipoprotein cholesterol,homeostasis model assessment(HOMA)-insulin resistance,and HOMA-βwere measured.Cystometry,common iliac artery wall thickness,and bladder tumor necrosis factor(TNF)-α,interleukin(IL)-6,transforming growth factor(TGF)-β1,Smad3,connective tissue growth factor(CTGF)and fibronectin were also evaluated.RESULTS Bladder weight and blood glucose,triglyceride,HOMA-insulin resistance,common iliac artery intima thickness,voided volume,intercontraction interval,bladder capacity,and mRNA expression of TNF-α,IL-6,TGF-β1,Smad3,CTGF and fibronectin were significantly increased at 4 weeks and 12 weeks after induction,while the HOMA-βlevel decreased at 4 weeks and 12 weeks,and the high-density lipoprotein cholesterol level decreased at 12 weeks.hAFSC-EVs treatment in DMA rats significantly reduced bladder weight and blood glucose,thickness of common iliac arterial intima,voided volume,intercontraction interval and bladder capacity at 4 weeks.The mRNA expression of TNF-α,TGF-β1,and CTGF in DMA rats treated with hAFSC-EVs were significantly decreased at 4 weeks,while the mRNA expressions of IL-6 and Smad3 were significantly decreased 12 weeks.CONCLUSION hAFSC-EVs treatment can help restore DMA-induced bladder dysfunction,which is associated with lowered blood glucose levels,reduced arterial wall thickness,and decreased TNF-α,IL-6,TGF-β1,Smad3,and CTGF expression.展开更多
Previous research has demonstrated the feasibility of repairing nerve defects through acellular allogeneic nerve grafting with bone marrow mesenchymal stem cells.However,adult tissue–derived mesenchymal stem cells en...Previous research has demonstrated the feasibility of repairing nerve defects through acellular allogeneic nerve grafting with bone marrow mesenchymal stem cells.However,adult tissue–derived mesenchymal stem cells encounter various obstacles,including limited tissue sources,invasive acquisition methods,cellular heterogeneity,purification challenges,cellular senescence,and diminished pluripotency and proliferation over successive passages.In this study,we used induced pluripotent stem cell-derived mesenchymal stem cells,known for their self-renewal capacity,multilineage differentiation potential,and immunomodulatory characteristics.We used induced pluripotent stem cell-derived mesenchymal stem cells in conjunction with acellular nerve allografts to address a 10 mm-long defect in a rat model of sciatic nerve injury.Our findings reveal that induced pluripotent stem cell-derived mesenchymal stem cells exhibit survival for up to 17 days in a rat model of peripheral nerve injury with acellular nerve allograft transplantation.Furthermore,the combination of acellular nerve allograft and induced pluripotent stem cell-derived mesenchymal stem cells significantly accelerates the regeneration of injured axons and improves behavioral function recovery in rats.Additionally,our in vivo and in vitro experiments indicate that induced pluripotent stem cell-derived mesenchymal stem cells play a pivotal role in promoting neovascularization.Collectively,our results suggest the potential of acellular nerve allografts with induced pluripotent stem cell-derived mesenchymal stem cells to augment nerve regeneration in rats,offering promising therapeutic strategies for clinical translation.展开更多
Mesenchymal stem cells(MSCs)are pluripotent stem cells isolated from human tissues.Due to their strong self-renewal capacity,pluripotency,and immunomodulatory properties,MSCs have garnered significant attention in cel...Mesenchymal stem cells(MSCs)are pluripotent stem cells isolated from human tissues.Due to their strong self-renewal capacity,pluripotency,and immunomodulatory properties,MSCs have garnered significant attention in cell therapy and tissue regeneration.However,cellular senescence induced by replication or external stimuli can impair MSC proliferation and differentiation,making it crucial to develop interventions that delay or reverse the senescence process.From a traditional Chinese medicine perspective,senescence stems from spleen and stomach deficiency,kidney deficiency,and related factors;thus,medicines that tonify the kidney and promote Qi and blood circulation play vital roles in anti-senescence therapy.Chinese medicine,characterized by low toxicity and multi-target,multi-functional properties,has become prominent in anti-senescence research.This paper examines the MSC senescence process by discussing its causes,characteristics,and mechanisms,then summarizes how active ingredients in herbal medicines and natural compounds reverse MSC senescence,facilitating the discovery of additional anti-senescence Chinese medicines and their effective components.展开更多
Eucalyptus(Eucalyptus camaldulensis Dehnh.)is an important exotic species in northern Nigeria commonly used for poles and timber.Sustainable management of this resource would require quantifying its volume.Stem taper ...Eucalyptus(Eucalyptus camaldulensis Dehnh.)is an important exotic species in northern Nigeria commonly used for poles and timber.Sustainable management of this resource would require quantifying its volume.Stem taper equations are one of the main and most efficient methods for estimating stem volume to any merchantable limit of a species.There is currently no taper equation for Eucalyptus species in Nigeria.Therefore,this study developed taper equations for E.camaldulensis in northern Nigeria.Data for this study were obtained from a private plantation in Jalingo Local Government Area,Taraba State,Nigeria.68 trees were felled and sectioned into 1-m bolt across the stem to a merchantable limit of 5 cm,which were used as the fitting dataset.An additional 22 trees were felled and used to validate the taper equations for stem volume estimation.Seven taper equations were initially fitted to the dataset using nonlinear least squares.The best taper equation was then refitted using a nonlinear mixed-effects approach and calibrated using diameters of one to five sections from the butt end.The taper equations were numerically integrated to obtain the stem volume,which was compared with empirical volume equations.The result shows that the Kozak(Can J For Res 27(5):619-629.10.1139/x97-011,1997)equation,which included eight parameters,provided the best fit for predicting section diameters for under and over bark.The mixed-effects taper equation(NLME-TE)explained most stem diameter variations in the fitting dataset(pseudo-R2:0.986-0.987;RMSE:0.547-0.578 cm)without substantial residual trends.The validation showed that the prediction accuracy of the integrated NLME-TE improved as the number of sectional diameter measurements increased,with at least a 35%reduction in volume estimate error.For practical implementation,two calibration sectional diameter measurements taken from the butt end per tree are recommended.This approach would reduce measurement effort and cost while improving model performance.展开更多
BACKGROUND Gastric cancer(GC)is one of the most common malignant tumors of the digestive system worldwide,the prognosis of patients with advanced GC remains poor.AIM To evaluate the combined expression characteristics...BACKGROUND Gastric cancer(GC)is one of the most common malignant tumors of the digestive system worldwide,the prognosis of patients with advanced GC remains poor.AIM To evaluate the combined expression characteristics of cancer stem cell markers CD24 and CD133 in GC pathological tissues,and to explore their association with patients’clinicopathological parameters and postoperative survival outcomes.METHODS A total of 304 GC patients who underwent surgical treatment in our hospital from January 2018 to January 2020 were retrospectively included.Immunohistochemistry was used to detect the protein expression of CD24 and CD133 in tumor tissues,adjacent tissues,and normal gastric mucosa tissues.Based on staining intensity and the proportion of positive cells,expression levels were classified into low and high expression,while clinicopathological parameters were recorded.χ2 test was used to evaluate the correlation between expression and categorical variables,Spearman rank correlation analysis was performed to assess the correlation between the expression intensities of the two markers,and multivariate regression models were applied to identify independent risk factors influencing co-expression.Kaplan-Meier survival curves and Log-rank test were used to compare survival differences among groups with different expression patterns.RESULTS Among the 304 patients,155 cases(50.99%)were CD24 positive,including 91 low-expression and 64 highexpression;133 cases(43.75%)were CD133 positive,including 81 low-expression and 52 high-expression.There were 74 cases(24.34%)with double positivity and 81 cases(26.64%)with double negativity.Compared with tumor tissues,the positive rates of CD24 and CD133 in normal gastric tissues and adjacent tissues were significantly lower(P<0.05).Univariate analysis showed that co-expression of CD24 and CD133 in GC tissues was significantly correlated with tumor size,Lauren classification,T stage,N stage,and vascular invasion(P<0.05),but not with patient age,gender,tumor site,World Health Organization histological classification,or M stage(P>0.05).Further multivariate regression analysis suggested that tumor size,T stage,N stage,and vascular invasion were independent risk factors promoting CD24 and CD133 double positivity.Spearman rank correlation analysis indicated a moderate positive correlation between their expression intensities(r=0.420,P<0.001).During follow-up,29 of 304 patients were lost(loss rate 9.54%);146 deaths occurred.According to expression combination,there were 89 cases of CD24 single positivity(39 deaths),68 cases of CD133 single positivity(31 deaths),81 cases of double negativity(25 deaths),and 66 cases of double positivity(51 deaths).Log-rank test showed significant differences in overall survival among the four groups(χ2=20.89,P<0.001),with CD24+/CD133+group showing the worst prognosis.CONCLUSION CD24 and CD133 exhibit high positive detection rates in GC tissues,and their co-positivity is closely associated with tumor stage progression and significantly indicates unfavorable survival outcomes.The co-expression of CD24/CD133 may reflect higher aggressiveness and metastatic potential of GC,serving as a potential prognostic marker and a direction for targeted therapeutic strategies.However,as this is a single-center retrospective study with limitations such as patient loss to follow-up and sample size,further prospective,multicenter,and mechanistic studies are required to validate its clinical applicability and biological role.展开更多
Adult neurogenesis continuously produces new neurons critical for cognitive plasticity in adult rodents.While it is known transforming growth factor-βsignaling is important in embryonic neurogenesis,its role in postn...Adult neurogenesis continuously produces new neurons critical for cognitive plasticity in adult rodents.While it is known transforming growth factor-βsignaling is important in embryonic neurogenesis,its role in postnatal neurogenesis remains unclear.In this study,to define the precise role of transforming growth factor-βsignaling in postnatal neurogenesis at distinct stages of the neurogenic cascade both in vitro and in vivo,we developed two novel inducible and cell type-specific mouse models to specifically silence transforming growth factor-βsignaling in neural stem cells in(mGFAPcre-ALK5fl/fl-Ai9)or immature neuroblasts in(DCXcreERT2-ALK5fl/fl-Ai9).Our data showed that exogenous transforming growth factor-βtreatment led to inhibition of the proliferation of primary neural stem cells while stimulating their migration.These effects were abolished in activin-like kinase 5(ALK5)knockout primary neural stem cells.Consistent with this,inhibition of transforming growth factor-βsignaling with SB-431542 in wild-type neural stem cells stimulated proliferation while inhibited the migration of neural stem cells.Interestingly,deletion of transforming growth factor-βreceptor in neural stem cells in vivo inhibited the migration of postnatal born neurons in mGFAPcre-ALK5fl/fl-Ai9 mice,while abolishment of transforming growth factor-βsignaling in immature neuroblasts in DCXcreERT2-ALK5fl/fl-Ai9 mice did not affect the migration of these cells in the hippocampus.In summary,our data supports a dual role of transforming growth factor-βsignaling in the proliferation and migration of neural stem cells in vitro.Moreover,our data provides novel insights on cell type-specific-dependent requirements of transforming growth factor-βsignaling on neural stem cell proliferation and migration in vivo.展开更多
基金supported by the National Natural Science Foundation of China,Nos.82471471(to WJ),82471485(to FY)Shaanxi Province Special Support Program for Leading Talents in Scientific and Technological Innovation,No.tzjhjw(to WJ)+1 种基金Shaanxi Key Research and Development Plan Project,No.2023-YBSF-353(to XW)the Joint Fund Project of Innovation Research Institute of Xijing Hospital,No.LHJJ24JH13(to ZS)。
文摘Epilepsy is a serious neurological disorder;however,the effectiveness of current medications is often suboptimal.Recently,stem cell technology has demonstrated remarkable therapeutic potential in addressing various neurological diseases,igniting interest in its applicability for epilepsy treatment.This comprehensive review summarizes different therapeutic approaches utilizing various types of stem cells.Preclinical experiments have explored the use and potential therapeutic effects of mesenchymal stem cells,including genetically modified variants.Clinical trials involving patientderived mesenchymal stem cells have shown promising results,with reductions in the frequency of epileptic seizures and improvements in neurological,cognitive,and motor functions reported.Another promising therapeutic strategy involves neural stem cells.These cells can be cultured outside the body and directed to differentiate into specific cell types.The transplant of neural stem cells has the potential to replace lost inhibitory interneurons,providing a novel treatment avenue for epilepsy.Embryonic stem cells are characterized by their significant capacity for self-renewal and their ability to differentiate into any type of somatic cell.In epilepsy treatment,embryonic stem cells can serve three primary functions:neuron regeneration,the maintenance of cellular homeostasis,and restorative activity.One notable strategy involves differentiating embryonic stem cells intoγ-aminobutyric acidergic neurons for transplantation into lesion sites.This approach is currently undergoing clinical trials and could be a breakthrough in the treatment of refractory epilepsy.Induced pluripotent stem cells share the same genetic background as the donor,thereby reducing the risk of immune rejection and addressing ethical concerns.However,research on induced pluripotent stem cell therapy remains in the preclinical stage.Despite the promise of stem cell therapies for epilepsy,several limitations must be addressed.Safety concerns persist,including issues such as tumor formation,and the low survival rate of transplanted cells remains a significant challenge.Additionally,the high cost of these treatments may be prohibitive for some patients.In summary,stem cell therapy shows considerable promise in managing epilepsy,but further research is needed to overcome its existing limitations and enhance its clinical applicability.
基金supported by the National Key Research and Development Program of China,No.2018YFA0108602the CAMS Initiative for Innovative Medicine,No.2021-1-I2M-019National High-Level Hospital Clinical Research Funding,No.2022-PUMCH-C-042(all to XB)。
文摘Ischemic stroke is a significant global health crisis,frequently resulting in disability or death,with limited therapeutic interventions available.Although various intrinsic reparative processes are initiated within the ischemic brain,these mechanisms are often insufficient to restore neuronal functionality.This has led to intensive investigation into the use of exogenous stem cells as a potential therapeutic option.This comprehensive review outlines the ontogeny and mechanisms of activation of endogenous neural stem cells within the adult brain following ischemic events,with focus on the impact of stem cell-based therapies on neural stem cells.Exogenous stem cells have been shown to enhance the proliferation of endogenous neural stem cells via direct cell-tocell contact and through the secretion of growth factors and exosomes.Additionally,implanted stem cells may recruit host stem cells from their niches to the infarct area by establishing so-called“biobridges.”Furthermore,xenogeneic and allogeneic stem cells can modify the microenvironment of the infarcted brain tissue through immunomodulatory and angiogenic effects,thereby supporting endogenous neuroregeneration.Given the convergence of regulatory pathways between exogenous and endogenous stem cells and the necessity for a supportive microenvironment,we discuss three strategies to simultaneously enhance the therapeutic efficacy of both cell types.These approaches include:(1)co-administration of various growth factors and pharmacological agents alongside stem cell transplantation to reduce stem cell apoptosis;(2)synergistic administration of stem cells and their exosomes to amplify paracrine effects;and(3)integration of stem cells within hydrogels,which provide a protective scaffold for the implanted cells while facilitating the regeneration of neural tissue and the reconstitution of neural circuits.This comprehensive review highlights the interactions and shared regulatory mechanisms between endogenous neural stem cells and exogenously implanted stem cells and may offer new insights for improving the efficacy of stem cell-based therapies in the treatment of ischemic stroke.
基金supported by the National Natural Science Foundation of China,Nos.82271132(to YL),82101167(to BB)the Natural Science Foundation of Chongqing,Nos.CSTB2022NSCQ-MSX0020(to BB),cstc2019jcyj-msxmX0473(to FC).
文摘Our previous study demonstrated that combined transplantation of bone marrow mesenchymal stem cells and retinal progenitor cells in rats has therapeutic effects on retinal degeneration that are superior to transplantation of retinal progenitor cells alone.Bone marrow mesenchymal stem cells regulate and interact with various cells in the retinal microenvironment by secreting neurotrophic factors and extracellular vesicles.Small extracellular vesicles derived from bone marrow mesenchymal stem cells,which offer low immunogenicity,minimal tumorigenic risk,and ease of transportation,have been utilized in the treatment of various neurological diseases.These vesicles exhibit various activities,including anti-inflammatory actions,promotion of tissue repair,and immune regulation.Therefore,novel strategies using human retinal progenitor cells combined with bone marrow mesenchymal stem cell-derived small extracellular vesicles may represent an innovation in stem cell therapy for retinal degeneration.In this study,we developed such an approach utilizing retinal progenitor cells combined with bone marrow mesenchymal stem cell-derived small extracellular vesicles to treat retinal degeneration in Royal College of Surgeons rats,a genetic model of retinal degeneration.Our findings revealed that the combination of bone marrow mesenchymal stem cell-derived small extracellular vesicles and retinal progenitor cells significantly improved visual function in these rats.The addition of bone marrow mesenchymal stem cell-derived small extracellular vesicles as adjuvants to stem cell transplantation with retinal progenitor cells enhanced the survival,migration,and differentiation of the exogenous retinal progenitor cells.Concurrently,these small extracellular vesicles inhibited the activation of regional microglia,promoted the migration of transplanted retinal progenitor cells to the inner nuclear layer of the retina,and facilitated their differentiation into photoreceptors and bipolar cells.These findings suggest that bone marrow mesenchymal stem cell-derived small extracellular vesicles potentiate the therapeutic efficacy of retinal progenitor cells in retinal degeneration by promoting their survival and differentiation.
基金supported by National Institutes of Health(R35NS137480,R35NS116843,and RF1AG079557)by Dr.Miriam and Sheldon G.Adelson Medical Research Foundation.
文摘The adult subventricular zone of the lateral ventricles and the subgranular zone in the hippocampal dentate gyrus(DG)are the two brain regions where neurogenesis occurs throughout life in the adult mammalian brain(Ming and Song,2011).Adult quiescent hippocampal neural stem cells(NSCs)are bona fide stem cells and,when activated,give rise to newborn granule neurons in the adult brain,which play vital roles in learning,memory,mood,and affective cognition(Bonaguidi et al.,2011;Ming and Song,2011).
文摘Bone regeneration for non-load-bearing defects remains a significant clinical challenge requiring advanced biomaterials and cellular strategies.Adiposederived mesenchymal stem cells(AD-MSCs)have garnered significant interest in bone tissue engineering(BTE)because of their abundant availability,minimally invasive harvesting procedures,and robust differentiation potential into osteogenic lineages.Unlike bone marrow-derived mesenchymal stem cells,AD-MSCs can be easily obtained in large quantities,making them appealing alternatives for therapeutic applications.This review explores hydrogels containing polymers,such as chitosan,collagen,gelatin,and hyaluronic acid,and their composites,tailored for BTE,and emphasizes the importance of these hydrogels as scaffolds for the delivery of AD-MSCs.Various hydrogel fabrication techniques and biocompatibility assessments are discussed,along with innovative modifications to enhance osteogenesis.This review also briefly outlines AD-MSC isolation methods and advanced embedding techniques for precise cell placement,such as direct encapsulation and three-dimensional bioprinting.We discuss the mechanisms of bone regeneration in the AD-MSC-laden hydrogels,including osteoinduction,vascularization,and extracellular matrix remodeling.We also review the preclinical and clinical applications of AD-MSC-hydrogel systems,emphasizing their success and limitations.In this review,we provide a comprehensive overview of AD-MSC-based hydrogel systems to guide the development of effective therapies for bone regeneration.
基金supported by the Hong Kong Research Grants Council Theme-based Research Scheme(Grant No.T12-716/22-R)Innovation and Technology Commission grant for State Key Laboratory of Liver Research(Grant No.ITC PD/17-9)University Development Fund of The University of Hong Kong,and Loke Yew Endowed Professorship award.I.O.L.Ng is Loke Yew Professor in Pathology.
文摘Hepatocellular carcinoma(HCC)is a pressing global health problem and is the sixth most common cancer and the third leading cause of cancer mortality worldwide.Despite continuous advances in treatment modalities,the 5-year survival rate is low with a high propensity for recurrence and metastasis1.This clinical challenge in treating HCC is largely attributed to the heterogeneity and intrinsic therapy resistance of cancer stem cells(CSCs),which are a subpopulation of cells with self-renewal capability and multidirectional differentiation potential to induce tumorigenicity2.The behavior and maintenance of CSCs are not autonomous but critically dependent on the complex bidirectional crosstalk between CSCs and the tumor immune microenvironment(TIME)1.In this review we first summarize the recent progress in characterizing CSCs and the interactions between CSCs and the TIME in HCC.Next,we discuss the emerging therapeutic strategies targeting CSC populations with the ongoing challenges.Finally,we give our perspectives on the future directions in HCC CSC research.
文摘A recently published prospective study marks a breakthrough for congenital olfactory disorders in children.The study provides the first long-term,three-year follow-up data,robustly demonstrating the durable efficacy and safety of autologous nasal epithelial stem cell transplantation.This work reveals immense therapeutic potential for a condition traditionally considered untreatable.However,this milestone achievement also presents new challenges.To translate this pioneering therapy from a single-center success to a global standard,multicenter,controlled clinical trials must be initiated immediately.Only through rigorous validation can we ensure its widespread adoption and ultimately bring hope to millions of children worldwide.
基金the Ministry of Science and Technology Taiwan,No.MOST 109-2314-B-182A-091,No.NSTC 112-2314-B-182A-062, No.NSTC 113-2314-B-182A-125.
文摘BACKGROUND The incidence of diabetic atherosclerosis(DMA)is increasing worldwide,but its pathogenesis remains incompletely understood.In addition to cardiovascular complications,bladder dysfunction is one of the common comorbidities associated with DMA but is often refractory to current treatments.AIM To investigate the therapeutic effect of human amniotic fluid stem cell-derived extracellular vesicles(hAFSC-EVs)on the recovery of bladder dysfunction in DMA rats.METHODS Eighty rats were divided into normal control,streptozotocin-induced diabetic rats,diabetic rats subjected to arterial balloon endothelial injury of common iliac artery(DMA),and DMA rats treated with hAFSC-EVs(DMA+hAFSC-EVs).At 4 weeks and 12 weeks after DMA induction,levels of blood glucose,total cholesterol,triglyceride,high-density lipoprotein cholesterol,low-density lipoprotein cholesterol,homeostasis model assessment(HOMA)-insulin resistance,and HOMA-βwere measured.Cystometry,common iliac artery wall thickness,and bladder tumor necrosis factor(TNF)-α,interleukin(IL)-6,transforming growth factor(TGF)-β1,Smad3,connective tissue growth factor(CTGF)and fibronectin were also evaluated.RESULTS Bladder weight and blood glucose,triglyceride,HOMA-insulin resistance,common iliac artery intima thickness,voided volume,intercontraction interval,bladder capacity,and mRNA expression of TNF-α,IL-6,TGF-β1,Smad3,CTGF and fibronectin were significantly increased at 4 weeks and 12 weeks after induction,while the HOMA-βlevel decreased at 4 weeks and 12 weeks,and the high-density lipoprotein cholesterol level decreased at 12 weeks.hAFSC-EVs treatment in DMA rats significantly reduced bladder weight and blood glucose,thickness of common iliac arterial intima,voided volume,intercontraction interval and bladder capacity at 4 weeks.The mRNA expression of TNF-α,TGF-β1,and CTGF in DMA rats treated with hAFSC-EVs were significantly decreased at 4 weeks,while the mRNA expressions of IL-6 and Smad3 were significantly decreased 12 weeks.CONCLUSION hAFSC-EVs treatment can help restore DMA-induced bladder dysfunction,which is associated with lowered blood glucose levels,reduced arterial wall thickness,and decreased TNF-α,IL-6,TGF-β1,Smad3,and CTGF expression.
基金supported by the National Natural Science Foundation of China,No.32171356(to YW)Self-Support Research Projects of Shihezi University,No.ZZZC2021105(to WJ)+1 种基金Capital Medical University Natural Science Cultivation Fund,No.PYZ23044(to FQM)Beijing Municipal Natural Science Foundation,No.7244410(to JHD)。
文摘Previous research has demonstrated the feasibility of repairing nerve defects through acellular allogeneic nerve grafting with bone marrow mesenchymal stem cells.However,adult tissue–derived mesenchymal stem cells encounter various obstacles,including limited tissue sources,invasive acquisition methods,cellular heterogeneity,purification challenges,cellular senescence,and diminished pluripotency and proliferation over successive passages.In this study,we used induced pluripotent stem cell-derived mesenchymal stem cells,known for their self-renewal capacity,multilineage differentiation potential,and immunomodulatory characteristics.We used induced pluripotent stem cell-derived mesenchymal stem cells in conjunction with acellular nerve allografts to address a 10 mm-long defect in a rat model of sciatic nerve injury.Our findings reveal that induced pluripotent stem cell-derived mesenchymal stem cells exhibit survival for up to 17 days in a rat model of peripheral nerve injury with acellular nerve allograft transplantation.Furthermore,the combination of acellular nerve allograft and induced pluripotent stem cell-derived mesenchymal stem cells significantly accelerates the regeneration of injured axons and improves behavioral function recovery in rats.Additionally,our in vivo and in vitro experiments indicate that induced pluripotent stem cell-derived mesenchymal stem cells play a pivotal role in promoting neovascularization.Collectively,our results suggest the potential of acellular nerve allografts with induced pluripotent stem cell-derived mesenchymal stem cells to augment nerve regeneration in rats,offering promising therapeutic strategies for clinical translation.
基金supported by Zhejiang Provincial Natural Science Foundation of China(No.LQ23H290006)the National Natural Science Foundation of China(No.82204781)+2 种基金the Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province(No.2020E10021)Zhejiang Provincial Program for the Cultivation of High-level Innovative Health Talents(No.ZWB-2020-18)Zhejiang Provincial Traditional Chinese Medicine Science and Technology Project(No.2023ZR119).
文摘Mesenchymal stem cells(MSCs)are pluripotent stem cells isolated from human tissues.Due to their strong self-renewal capacity,pluripotency,and immunomodulatory properties,MSCs have garnered significant attention in cell therapy and tissue regeneration.However,cellular senescence induced by replication or external stimuli can impair MSC proliferation and differentiation,making it crucial to develop interventions that delay or reverse the senescence process.From a traditional Chinese medicine perspective,senescence stems from spleen and stomach deficiency,kidney deficiency,and related factors;thus,medicines that tonify the kidney and promote Qi and blood circulation play vital roles in anti-senescence therapy.Chinese medicine,characterized by low toxicity and multi-target,multi-functional properties,has become prominent in anti-senescence research.This paper examines the MSC senescence process by discussing its causes,characteristics,and mechanisms,then summarizes how active ingredients in herbal medicines and natural compounds reverse MSC senescence,facilitating the discovery of additional anti-senescence Chinese medicines and their effective components.
文摘Eucalyptus(Eucalyptus camaldulensis Dehnh.)is an important exotic species in northern Nigeria commonly used for poles and timber.Sustainable management of this resource would require quantifying its volume.Stem taper equations are one of the main and most efficient methods for estimating stem volume to any merchantable limit of a species.There is currently no taper equation for Eucalyptus species in Nigeria.Therefore,this study developed taper equations for E.camaldulensis in northern Nigeria.Data for this study were obtained from a private plantation in Jalingo Local Government Area,Taraba State,Nigeria.68 trees were felled and sectioned into 1-m bolt across the stem to a merchantable limit of 5 cm,which were used as the fitting dataset.An additional 22 trees were felled and used to validate the taper equations for stem volume estimation.Seven taper equations were initially fitted to the dataset using nonlinear least squares.The best taper equation was then refitted using a nonlinear mixed-effects approach and calibrated using diameters of one to five sections from the butt end.The taper equations were numerically integrated to obtain the stem volume,which was compared with empirical volume equations.The result shows that the Kozak(Can J For Res 27(5):619-629.10.1139/x97-011,1997)equation,which included eight parameters,provided the best fit for predicting section diameters for under and over bark.The mixed-effects taper equation(NLME-TE)explained most stem diameter variations in the fitting dataset(pseudo-R2:0.986-0.987;RMSE:0.547-0.578 cm)without substantial residual trends.The validation showed that the prediction accuracy of the integrated NLME-TE improved as the number of sectional diameter measurements increased,with at least a 35%reduction in volume estimate error.For practical implementation,two calibration sectional diameter measurements taken from the butt end per tree are recommended.This approach would reduce measurement effort and cost while improving model performance.
基金National Natural Science Foundation of China,No.82003223and China Postdoctoral Science Foundation,No.2020M671398.
文摘BACKGROUND Gastric cancer(GC)is one of the most common malignant tumors of the digestive system worldwide,the prognosis of patients with advanced GC remains poor.AIM To evaluate the combined expression characteristics of cancer stem cell markers CD24 and CD133 in GC pathological tissues,and to explore their association with patients’clinicopathological parameters and postoperative survival outcomes.METHODS A total of 304 GC patients who underwent surgical treatment in our hospital from January 2018 to January 2020 were retrospectively included.Immunohistochemistry was used to detect the protein expression of CD24 and CD133 in tumor tissues,adjacent tissues,and normal gastric mucosa tissues.Based on staining intensity and the proportion of positive cells,expression levels were classified into low and high expression,while clinicopathological parameters were recorded.χ2 test was used to evaluate the correlation between expression and categorical variables,Spearman rank correlation analysis was performed to assess the correlation between the expression intensities of the two markers,and multivariate regression models were applied to identify independent risk factors influencing co-expression.Kaplan-Meier survival curves and Log-rank test were used to compare survival differences among groups with different expression patterns.RESULTS Among the 304 patients,155 cases(50.99%)were CD24 positive,including 91 low-expression and 64 highexpression;133 cases(43.75%)were CD133 positive,including 81 low-expression and 52 high-expression.There were 74 cases(24.34%)with double positivity and 81 cases(26.64%)with double negativity.Compared with tumor tissues,the positive rates of CD24 and CD133 in normal gastric tissues and adjacent tissues were significantly lower(P<0.05).Univariate analysis showed that co-expression of CD24 and CD133 in GC tissues was significantly correlated with tumor size,Lauren classification,T stage,N stage,and vascular invasion(P<0.05),but not with patient age,gender,tumor site,World Health Organization histological classification,or M stage(P>0.05).Further multivariate regression analysis suggested that tumor size,T stage,N stage,and vascular invasion were independent risk factors promoting CD24 and CD133 double positivity.Spearman rank correlation analysis indicated a moderate positive correlation between their expression intensities(r=0.420,P<0.001).During follow-up,29 of 304 patients were lost(loss rate 9.54%);146 deaths occurred.According to expression combination,there were 89 cases of CD24 single positivity(39 deaths),68 cases of CD133 single positivity(31 deaths),81 cases of double negativity(25 deaths),and 66 cases of double positivity(51 deaths).Log-rank test showed significant differences in overall survival among the four groups(χ2=20.89,P<0.001),with CD24+/CD133+group showing the worst prognosis.CONCLUSION CD24 and CD133 exhibit high positive detection rates in GC tissues,and their co-positivity is closely associated with tumor stage progression and significantly indicates unfavorable survival outcomes.The co-expression of CD24/CD133 may reflect higher aggressiveness and metastatic potential of GC,serving as a potential prognostic marker and a direction for targeted therapeutic strategies.However,as this is a single-center retrospective study with limitations such as patient loss to follow-up and sample size,further prospective,multicenter,and mechanistic studies are required to validate its clinical applicability and biological role.
基金supported by NIH grants,Nos.R01NS125074,R01AG083164,R01NS107365,and R21NS127177(to YL),1F31NS129204-01A1(to KW)and Albert Ryan Fellowship(to KW).
文摘Adult neurogenesis continuously produces new neurons critical for cognitive plasticity in adult rodents.While it is known transforming growth factor-βsignaling is important in embryonic neurogenesis,its role in postnatal neurogenesis remains unclear.In this study,to define the precise role of transforming growth factor-βsignaling in postnatal neurogenesis at distinct stages of the neurogenic cascade both in vitro and in vivo,we developed two novel inducible and cell type-specific mouse models to specifically silence transforming growth factor-βsignaling in neural stem cells in(mGFAPcre-ALK5fl/fl-Ai9)or immature neuroblasts in(DCXcreERT2-ALK5fl/fl-Ai9).Our data showed that exogenous transforming growth factor-βtreatment led to inhibition of the proliferation of primary neural stem cells while stimulating their migration.These effects were abolished in activin-like kinase 5(ALK5)knockout primary neural stem cells.Consistent with this,inhibition of transforming growth factor-βsignaling with SB-431542 in wild-type neural stem cells stimulated proliferation while inhibited the migration of neural stem cells.Interestingly,deletion of transforming growth factor-βreceptor in neural stem cells in vivo inhibited the migration of postnatal born neurons in mGFAPcre-ALK5fl/fl-Ai9 mice,while abolishment of transforming growth factor-βsignaling in immature neuroblasts in DCXcreERT2-ALK5fl/fl-Ai9 mice did not affect the migration of these cells in the hippocampus.In summary,our data supports a dual role of transforming growth factor-βsignaling in the proliferation and migration of neural stem cells in vitro.Moreover,our data provides novel insights on cell type-specific-dependent requirements of transforming growth factor-βsignaling on neural stem cell proliferation and migration in vivo.
