Photobiomodulation:a novel approach to promote trans-differentiation of adipose-derived stem cells into neuronal-like cells

Photobiomodulation,originally used red and near-infrared lasers,can alter cellular metabolism.It has been demonstrated that the visible spectrum at 451-540 nm does not necessarily increase cell proliferation,near-infrared light promotes adipose stem cell proliferation and affects adipose stem cell migration,which is necessary for the cells homing to the site of injury.In this in vitro study,we explored the potential of adipose-derived stem cells to differentiate into neurons for future translational regenerative treatments in neurodegenerative disorders and brain injuries.We investigated the effects of various biological and chemical inducers on trans-differentiation and evaluated the impact of photobiomodulation using 825 nm near-infrared and 525 nm green laser light at 5 J/cm2.As adipose-derived stem cells can be used in autologous grafting and photobiomodulation has been shown to have biostimulatory effects.Our findings reveal that adipose-derived stem cells can indeed trans-differentiate into neuronal cells when exposed to inducers,with pre-induced cells exhibiting higher rates of proliferation and trans-differentiation compared with the control group.Interestingly,green laser light stimulation led to notable morphological changes indicative of enhanced trans-differentiation,while near-infrared photobiomodulation notably increased the expression of neuronal markers.Through biochemical analysis and enzyme-linked immunosorbent assays,we observed marked improvements in viability,proliferation,membrane permeability,and mitochondrial membrane potential,as well as increased protein levels of neuron-specific enolase and ciliary neurotrophic factor.Overall,our results demonstrate the efficacy of photobiomodulation in enhancing the trans-differentiation ability of adipose-derived stem cells,offering promising prospects for their use in regenerative medicine for neurodegenerative disorders and brain injuries.

Mechanism of inflammatory response and therapeutic effects of stem cells in ischemic stroke:current evidence and future perspectives

Ischemic stroke is a leading cause of death and disability worldwide,with an increasing trend and tendency for onset at a younger age.China,in particular,bears a high burden of stroke cases.In recent years,the inflammatory response after stroke has become a research hotspot:understanding the role of inflammatory response in tissue damage and repair following ischemic stroke is an important direction for its treatment.This review summarizes several major cells involved in the inflammatory response following ischemic stroke,including microglia,neutrophils,monocytes,lymphocytes,and astrocytes.Additionally,we have also highlighted the recent progress in various treatments for ischemic stroke,particularly in the field of stem cell therapy.Overall,understanding the complex interactions between inflammation and ischemic stroke can provide valuable insights for developing treatment strategies and improving patient outcomes.Stem cell therapy may potentially become an important component of ischemic stroke treatment.

Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury

Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological recovery.However,the mechanism of CXCR4 upregulation in induced neural stem cells remains unclear.In this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 expression.However,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial activation.In agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury mice.Notably,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head injury.In conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neural stem cells on microglial activation via upregulation of CXCR4 and Crry,thereby promoting induced neural stem cell–mediated improvement of neuronal injury,cerebral edema,and neurological disorders following closed head injury.

Advances in therapies using mesenchymal stem cells and their exosomes for treatment of peripheral nerve injury:state of the art and future perspectives

“Peripheral nerve injury”refers to damage or trauma affecting nerves outside the brain and spinal cord.Peripheral nerve injury results in movements or sensation impairments,and represents a serious public health problem.Although severed peripheral nerves have been effectively joined and various therapies have been offered,recovery of sensory or motor functions remains limited,and efficacious therapies for complete repair of a nerve injury remain elusive.The emerging field of mesenchymal stem cells and their exosome-based therapies hold promise for enhancing nerve regeneration and function.Mesenchymal stem cells,as large living cells responsive to the environment,secrete various factors and exosomes.The latter are nano-sized extracellular vesicles containing bioactive molecules such as proteins,microRNA,and messenger RNA derived from parent mesenchymal stem cells.Exosomes have pivotal roles in cell-to-cell communication and nervous tissue function,offering solutions to changes associated with cell-based therapies.Despite ongoing investigations,mesenchymal stem cells and mesenchymal stem cell-derived exosome-based therapies are in the exploratory stage.A comprehensive review of the latest preclinical experiments and clinical trials is essential for deep understanding of therapeutic strategies and for facilitating clinical translation.This review initially explores current investigations of mesenchymal stem cells and mesenchymal stem cell-derived exosomes in peripheral nerve injury,exploring the underlying mechanisms.Subsequently,it provides an overview of the current status of mesenchymal stem cell and exosomebased therapies in clinical trials,followed by a comparative analysis of therapies utilizing mesenchymal stem cells and exosomes.Finally,the review addresses the limitations and challenges associated with use of mesenchymal stem cell-derived exosomes,offering potential solutions and guiding future directions.

Therapeutic potential of stem cells in subarachnoid hemorrhage

Aneurysm rupture can result in subarachnoid hemorrhage,a condition with potentially severe consequences,such as disability and death.In the acute stage,early brain injury manifests as intracranial pressure elevation,global cerebral ischemia,acute hydrocephalus,and direct blood–brain contact due to aneurysm rupture.This may subsequently cause delayed cerebral infarction,often with cerebral vasospasm,significantly affecting patient outcomes.Chronic complications such as brain volume loss and chronic hydrocephalus can further impact outcomes.Investigating the mechanisms of subarachnoid hemorrhage-induced brain injury is paramount for identifying effective treatments.Stem cell therapy,with its multipotent differentiation capacity and anti-inflammatory effects,has emerged as a promising approach for treating previously deemed incurable conditions.This review focuses on the potential application of stem cells in subarachnoid hemorrhage pathology and explores their role in neurogenesis and as a therapeutic intervention in preclinical and clinical subarachnoid hemorrhage studies.

Exosomes originating from neural stem cells undergoing necroptosis participate in cellular communication by inducing TSC2 upregulation of recipient cells following spinal cord injury

We previously demonstrated that inhibiting neural stem cells necroptosis enhances functional recovery after spinal cord injury.While exosomes are recognized as playing a pivotal role in neural stem cells exocrine function,their precise function in spinal cord injury remains unclear.To investigate the role of exosomes generated following neural stem cells necroptosis after spinal cord injury,we conducted singlecell RNA sequencing and validated that neural stem cells originate from ependymal cells and undergo necroptosis in response to spinal cord injury.Subsequently,we established an in vitro necroptosis model using neural stem cells isolated from embryonic mice aged 16-17 days and extracted exosomes.The results showed that necroptosis did not significantly impact the fundamental characteristics or number of exosomes.Transcriptome sequencing of exosomes in necroptosis group identified 108 differentially expressed messenger RNAs,104 long non-coding RNAs,720 circular RNAs,and 14 microRNAs compared with the control group.Construction of a competing endogenous RNA network identified the following hub genes:tuberous sclerosis 2(Tsc2),solute carrier family 16 member 3(Slc16a3),and forkhead box protein P1(Foxp1).Notably,a significant elevation in TSC2 expression was observed in spinal cord tissues following spinal cord injury.TSC2-positive cells were localized around SRY-box transcription factor 2-positive cells within the injury zone.Furthermore,in vitro analysis revealed increased TSC2 expression in exosomal receptor cells compared with other cells.Further assessment of cellular communication following spinal cord injury showed that Tsc2 was involved in ependymal cellular communication at 1 and 3 days post-injury through the epidermal growth factor and midkine signaling pathways.In addition,Slc16a3 participated in cellular communication in ependymal cells at 7 days post-injury via the vascular endothelial growth factor and macrophage migration inhibitory factor signaling pathways.Collectively,these findings confirm that exosomes derived from neural stem cells undergoing necroptosis play an important role in cellular communication after spinal cord injury and induce TSC2 upregulation in recipient cells.

Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis

Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological damage.Hypoxic preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are unknown.To this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB pathways.Subsequently,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by asphyxia.The results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these effects.To conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.

Targeting STAT3 with SH-4-54 suppresses stemness and chemoresistance in cancer stem-like cells derived from colorectal cancer

BACKGROUND Over the years,the numbers of treatment options for colorectal cancer(CRC)have increased,leading to notable improvements in the overall survival of CRC patients.Although therapy may initially yield positive results,the development of drug resistance can result in treatment failure and cancer recurrence.This resistance is often attributed to the presence of cancer stem cells(CSCs).These CSCs not only contribute to therapeutic resistance but also play crucial roles in the initiation and development of tumor metastasis.AIM To investigate the antitumor effects of SH-4-54,which are mediated by targeting CSCs relative to treatment outcomes.METHODS CSCs were enriched by culturing CRC cells in serum-free medium.Hallmarks of stemness and IL-6/JAK2/STAT3 signaling were detected by Western blotting.Indicators of CSC malignancy,including proliferation,invasion,and tumor formation,were measured.RESULTS In this study,we employed SH-4-54,which exhibits anticancer activity in solid tumors through targeting the SH2 domain of both the signal transducer and activator of transcription(STAT)3 and the STAT5,and evaluated its effects on stemness and chemoresistance in colorectal CSCs.As expected,SH-4-54 treatment inhibited the phosphorylation of STAT3(p-STAT3)and decreased the percentage of ALDH1A1-positive CRC cells.The addition of SH-4-54 dissociated colorectal spheroids and decreased the expression of stemness markers,including ALDH1A1,CD44 and Nanog.SH-4-54 treatment decreased IL-6/JAK2/STAT3 signaling by inhibiting p-STAT3 and thus inhibited spheroid formation by SW480 and LoVo cells.Moreover,SH-4-54 treatment inhibited indicators of malignancy,including cell proliferation,invasion,and tumor formation,in CSCs in vitro and in vivo.Notably,SH-4-54 treatment significantly increased chemosensitivity to oxaplatin.CONCLUSION Taken together,these results indicate that SH-4-54 is a promising molecule that exerts antitumor effects on colorectal CSCs by inhibiting STAT3 signaling.

Unlocking the versatile potential:Adipose-derived mesenchymal stem cells in ocular surface reconstruction and oculoplastics

This review comprehensively explores the versatile potential of mesenchymal stem cells(MSCs)with a specific focus on adipose-derived MSCs.Ophthalmic and oculoplastic surgery,encompassing diverse procedures for ocular and periocular enhancement,demands advanced solutions for tissue restoration,functional and aesthetic refinement,and aging.Investigating immunomodulatory,regenerative,and healing capacities of MSCs,this review underscores the potential use of adipose-derived MSCs as a cost-effective alternative from bench to bedside,addressing common unmet needs in the field of reconstructive and regenerative surgery.

Immunomodulation of adipose-derived mesenchymal stem cells on peripheral blood mononuclear cells in colorectal cancer patients with COVID-19

BACKGROUND Accumulating evidence has shown that adipose tissue-derived mesenchymal stem cells(ADSCs)are an effective therapeutic approach for managing coronavirus disease 2019(COVID-19);however,further elucidation is required to determine their underlying immunomodulatory effect on the mRNA expression of T helper cell-related transcription factors(TFs)and cytokine release in peripheral blood mononuclear cells(PBMCs).AIM To investigate the impact of ADSCs on the mRNA expression of TFs and cytokine release in PBMCs from colorectal cancer(CRC)patients with severe COVID-19(CRC^(+)patients).METHODS PBMCs from CRC^(+)patients(PBMCs-C+)and age-matched CRC patients(PBMCs-C)were stimulated and cultured in the presence/absence of ADSCs.The mRNA levels of T-box TF TBX21(T-bet),GATA binding protein 3(GATA-3),RAR-related orphan receptor C(RORC),and forkhead box P3(FoxP3)in the PBMCs were determined by reverse transcriptase-polymerase chain reaction.Culture supernatants were evaluated for levels of interferon gamma(IFN-γ),interleukin 4(IL-4),IL-17A,and transforming growth factor beta 1(TGF-β1)using an enzyme-linked immunosorbent assay.RESULTS Compared with PBMCs-C,PBMCs-C+exhibited higher mRNA levels of T-bet and RORC,and increased levels of IFN-γ and IL-17A.Additionally,a significant decrease in FoxP3 mRNA and TGF-β1,as well as an increase in Tbet/GATA-3,RORC/FoxP3,IFN-γ/IL-4,and IL-17A/TGF-β1 ratios were observed in PBMCs-C+.Furthermore,ADSCs significantly induced a functional regulatory T cell(Treg)subset,as evidenced by an increase in FoxP3 mRNA and TGF-β1 release levels.This was accompanied by a significant decrease in the mRNA levels of T-bet and RORC,release of IFN-γ and IL-17A,and T-bet/GATA-3,RORC/FoxP3,IFN-γ/IL-4,and IL-17A/TGF-β1 ratios,compared with the PBMCs-C+alone.CONCLUSION The present in vitro studies showed that ADSCs contributed to the immunosuppressive effects on PBMCs-C+,favoring Treg responses.Thus,ADSC-based cell therapy could be a beneficial approach for patients with severe COVID-19 who fail to respond to conventional therapies.

Adipose-derived stem cells in diabetic foot care:Bridging clinical trials and practical application

Diabetic foot ulcers(DFUs)pose a critical medical challenge,significantly impairing the quality of life of patients.Adipose-derived stem cells(ADSCs)have been identified as a promising therapeutic approach for improving wound healing in DFUs.Despite extensive exploration of the mechanical aspects of ADSC therapy against DFU,its clinical applications remain elusive.In this review,we aimed to bridge this gap by evaluating the use and advancements of ADSCs in the clinical management of DFUs.The review begins with a discussion of the classification and clinical management of diabetic foot conditions.It then discusses the current landscape of clinical trials,focusing on their geographic distribution,reported efficacy,safety profiles,treatment timing,administration techniques,and dosing considerations.Finally,the review discusses the preclinical strategies to enhance ADSC efficacy.This review shows that many trials exhibit biases in study design,unclear inclusion criteria,and intervention protocols.In conclusion,this review underscores the potential of ADSCs in DFU treatment and emphasizes the critical need for further research and refinement of therapeutic approaches,with a focus on improving the quality of future clinical trials to enhance treatment outcomes and advance the field of diabetic wound care.

Adipose-derived stem cells and knee osteoarthritis:New perspectives,old concerns

In this editorial,we comment on the paper by Muthu et al published in the recent issue of the journal.This editorial review focusses on the use of adipose-derived stem cells(ADSCs)in knee osteoarthritis treatment.We discuss the differences between the stromal vascular fraction and microfragmented adipose tissue and highlight the results of clinical studies comparing both treatments and the use of hyaluronic acid,platelet-rich plasma,and bone marrow aspirate concentrate.The use of expanded ADSCs is also discussed;moreover,concerns regarding treatment with ADSCs,particularly the heterogeneity of published studies and the need to standardize protocols to explore clinical potential is explored.

Non-enzymatic methods for isolation of stromal vascular fraction and adipose-derived stem cells:A systematic review

BACKGROUND Adipose-derived stem cells(ADSCs)and the stromal vascular fraction(SVF)have garnered substantial interest in regenerative medicine due to their potential to treat a wide range of conditions.Traditional enzymatic methods for isolating these cells face challenges such as high costs,lengthy processing time,and regulatory complexities.AIM This systematic review aimed to assess the efficacy and practicality of nonenzymatic,mechanical methods for isolating SVF and ADSCs,comparing these to conventional enzymatic approaches.METHODS Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines,a comprehensive literature search was conducted across multiple databases.Studies were selected based on inclusion criteria focused on non-enzymatic isolation methods for SVF and ADSCs from adipose tissue.The risk of bias was assessed,and a qualitative synthesis of findings was performed due to the methodological heterogeneity of the included studies.RESULTS Nineteen studies met the inclusion criteria,highlighting various mechanical techniques such as centrifugation,vortexing,and ultrasonic cavitation.The review identified significant variability in cell yield and viability,and the integrity of isolated cells across different non-enzymatic methods compared to enzymatic procedures.Despite some advantages of mechanical methods,including reduced processing time and avoidance of enzymatic reagents,the evidence suggests a need for optimization to match the cell quality and therapeutic efficacy achievable with enzymatic isolation.CONCLUSION Non-enzymatic,mechanical methods offer a promising alternative to enzymatic isolation of SVF and ADSCs,potentially simplifying the isolation process and reducing regulatory hurdles.However,further research is necessary to standardize these techniques and ensure consistent,high-quality cell yields for clinical applications.The development of efficient,safe,and reproducible non-enzymatic isolation methods could significantly advance the field of regenerative medicine.

A Review on the Biological Characteristics and Secretory Functions of Adipose-derived Mesenchymal Stem Cells

Adipose-derived mesenchymal stem cells （ADSCs） can be largely and easily obtained from a wide range of sources. Moreover, they have self-renewal ability, multi-differentiation potential, and an important role in immune regulation. They can secrete a variety of cytokines to regulate the in vivo micro-environment. Therefore, ADSCs are the ideal seed ceils for stem ceils application. This paper reviews the location, isolation, surface markers, proliferation, differentiation and other biological characteristics of ADSCs, as well as their secretory function and relative researches. ADSCs are expected to become excellent seed cells for cell therapy and tissue engineering through in-depth studies.

The combined application of stem cells and three-dimensional bioprinting scaffolds for the repair of spinal cord injury

Spinal cord injury is considered one of the most difficult injuries to repair and has one of the worst prognoses for injuries to the nervous system.Following surgery,the poor regenerative capacity of nerve cells and the generation of new scars can make it very difficult for the impaired nervous system to restore its neural functionality.Traditional treatments can only alleviate secondary injuries but cannot fundamentally repair the spinal cord.Consequently,there is a critical need to develop new treatments to promote functional repair after spinal cord injury.Over recent years,there have been seve ral developments in the use of stem cell therapy for the treatment of spinal cord injury.Alongside significant developments in the field of tissue engineering,three-dimensional bioprinting technology has become a hot research topic due to its ability to accurately print complex structures.This led to the loading of three-dimensional bioprinting scaffolds which provided precise cell localization.These three-dimensional bioprinting scaffolds co uld repair damaged neural circuits and had the potential to repair the damaged spinal cord.In this review,we discuss the mechanisms underlying simple stem cell therapy,the application of different types of stem cells for the treatment of spinal cord injury,and the different manufa cturing methods for three-dimensional bioprinting scaffolds.In particular,we focus on the development of three-dimensional bioprinting scaffolds for the treatment of spinal cord injury.

Autophagy in neural stem cells and glia for brain health and diseases

Autophagy is a multifaceted cellular process that not only maintains the homeostatic and adaptive responses of the brain but is also dynamically involved in the regulation of neural cell generation,maturation,and survival.Autophagy facilities the utilization of energy and the microenvironment for developing neural stem cells.Autophagy arbitrates structural and functional remodeling during the cell differentiation process.Autophagy also plays an indispensable role in the maintenance of stemness and homeostasis in neural stem cells during essential brain physiology and also in the instigation and progression of diseases.Only recently,studies have begun to shed light on autophagy regulation in glia(microglia,astrocyte,and oligodendrocyte)in the brain.Glial cells have attained relatively less consideration despite their unquestioned influence on various aspects of neural development,synaptic function,brain metabolism,cellular debris clearing,and restoration of damaged or injured tissues.Thus,this review composes pertinent information regarding the involvement of autophagy in neural stem cells and glial regulation and the role of this connexion in normal brain functions,neurodevelopmental disorders,and neurodegenerative diseases.This review will provide insight into establishing a concrete strategic approach for investigating pathological mechanisms and developing therapies for brain diseases.

Neural stem cells promote neuroplasticity: a promising therapeutic strategy for the treatment of Alzheimer’s disease

Recent studies have demonstrated that neuroplasticity,such as synaptic plasticity and neurogenesis,exists throughout the normal lifespan but declines with age and is significantly impaired in individuals with Alzheimer’s disease.Hence,promoting neuroplasticity may represent an effective strategy with which Alzheimer’s disease can be alleviated.Due to their significant ability to self-renew,differentiate,and migrate,neural stem cells play an essential role in reversing synaptic and neuronal damage,reducing the pathology of Alzheimer’s disease,including amyloid-β,tau protein,and neuroinflammation,and secreting neurotrophic factors and growth factors that are related to plasticity.These events can promote synaptic plasticity and neurogenesis to repair the microenvironment of the mammalian brain.Consequently,neural stem cells are considered to represent a potential regenerative therapy with which to improve Alzheimer’s disease and other neurodegenerative diseases.In this review,we discuss how neural stem cells regulate neuroplasticity and optimize their effects to enhance their potential for treating Alzheimer’s disease in the clinic.

Priming mesenchymal stem cells to develop “super stem cells”

The stem cell pre-treatment approaches at cellular and sub-cellular levels encompass physical manipulation of stem cells to growth factor treatment,genetic manipulation,and chemical and pharmacological treatment,each strategy having advantages and limitations.Most of these pre-treatment protocols are non-combinative.This editorial is a continuum of Li et al’s published article and Wan et al’s editorial focusing on the significance of pre-treatment strategies to enhance their stemness,immunoregulatory,and immunosuppressive properties.They have elaborated on the intricacies of the combinative pre-treatment protocol using pro-inflammatory cytokines and hypoxia.Applying a well-defined multi-pronged combinatorial strategy of mesenchymal stem cells(MSCs),pre-treatment based on the mechanistic understanding is expected to develop“Super MSCs”,which will create a transformative shift in MSC-based therapies in clinical settings,potentially revolutionizing the field.Once optimized,the standardized protocols may be used with slight modifications to pre-treat different stem cells to develop“super stem cells”with augmented stemness,functionality,and reparability for diverse clinical applications with better outcomes.

Conditioned medium from human dental pulp stem cells treats spinal cord injury by inhibiting microglial pyroptosis

Human dental pulp stem cell transplantation has been shown to be an effective therapeutic strategy for spinal cord injury.However,whether the human dental pulp stem cell secretome can contribute to functional recovery after spinal cord injury remains unclear.In the present study,we established a rat model of spinal cord injury based on impact injury from a dropped weight and then intraperitoneally injected the rats with conditioned medium from human dental pulp stem cells.We found that the conditioned medium effectively promoted the recovery of sensory and motor functions in rats with spinal cord injury,decreased expression of the microglial pyroptosis markers NLRP3,GSDMD,caspase-1,and interleukin-1β,promoted axonal and myelin regeneration,and inhibited the formation of glial scars.In addition,in a lipopolysaccharide-induced BV2 microglia model,conditioned medium from human dental pulp stem cells protected cells from pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway.These results indicate that conditioned medium from human dental pulp stem cells can reduce microglial pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway,thereby promoting the recovery of neurological function after spinal cord injury.Therefore,conditioned medium from human dental pulp stem cells may become an alternative therapy for spinal cord injury.

Long non-coding RNA H19 regulates neurogenesis of induced neural stem cells in a mouse model of closed head injury

Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regeneration via cell replacement.However,the neural regeneration efficiency of induced neural stem cells remains limited.In this study,we explored differentially expressed genes and long non-coding RNAs to clarify the mechanism underlying the neurogenesis of induced neural stem cells.We found that H19 was the most downregulated neurogenesis-associated lnc RNA in induced neural stem cells compared with induced pluripotent stem cells.Additionally,we demonstrated that H19 levels in induced neural stem cells were markedly lower than those in induced pluripotent stem cells and were substantially higher than those in induced neural stem cell-derived neurons.We predicted the target genes of H19 and discovered that H19 directly interacts with mi R-325-3p,which directly interacts with Ctbp2 in induced pluripotent stem cells and induced neural stem cells.Silencing H19 or Ctbp2 impaired induced neural stem cell proliferation,and mi R-325-3p suppression restored the effect of H19 inhibition but not the effect of Ctbp2 inhibition.Furthermore,H19 silencing substantially promoted the neural differentiation of induced neural stem cells and did not induce apoptosis of induced neural stem cells.Notably,silencing H19 in induced neural stem cell grafts markedly accelerated the neurological recovery of closed head injury mice.Our results reveal that H19 regulates the neurogenesis of induced neural stem cells.H19 inhibition may promote the neural differentiation of induced neural stem cells,which is closely associated with neurological recovery following closed head injury.