Neural injuries can cause considerable functional impairments,and both central and peripheral nervous systems have limited regenerative capacity.The existing conventional pharmacological treatments in clinical practic...Neural injuries can cause considerable functional impairments,and both central and peripheral nervous systems have limited regenerative capacity.The existing conventional pharmacological treatments in clinical practice show poor targeting,rapid drug clearance from the circulatory system,and low therapeutic efficiency.Therefore,in this review,we have first described the mechanisms underlying nerve regeneration,characterized the biomaterials used for drug delivery to facilitate nerve regeneration,and highlighted the functionalization strategies used for such drug-delivery systems.These systems mainly use natural and synthetic polymers,inorganic materials,and hybrid systems with advanced drug-delivery abilities,including nanoparticles,hydrogels,and scaffoldbased systems.Then,we focused on comparing the types of drug-delivery systems for neural regeneration as well as the mechanisms and challenges associated with targeted delivery of drugs to facilitate neural regeneration.Finally,we have summarized the clinical application research and limitations of targeted delivery of these drugs.These biomaterials and drug-delivery systems can provide mechanical support,sustained release of bioactive molecules,and enhanced intercellular contact,ultimately reducing cell apoptosis and enhancing functional recovery.Nevertheless,immune reactions,degradation regulation,and clinical translations remain major unresolved challenges.Future studies should focus on optimizing biomaterial properties,refining delivery precision,and overcoming translational barriers to advance these technologies toward clinical applications.展开更多
Retinal ganglion cells,a crucial component of the central nervous system,are often affected by irreversible visual impairment due to various conditions,including trauma,tumors,ischemia,and glaucoma.Studies have shown ...Retinal ganglion cells,a crucial component of the central nervous system,are often affected by irreversible visual impairment due to various conditions,including trauma,tumors,ischemia,and glaucoma.Studies have shown that the optic nerve crush model and glaucoma model are commonly used to study retinal ganglion cell injury.While these models differ in their mechanisms,both ultimately result in retinal ganglion cell injury.With advancements in high-throughput technologies,techniques such as microarray analysis,RNA sequencing,and single-cell RNA sequencing have been widely applied to characterize the transcriptomic profiles of retinal ganglion cell injury,revealing underlying molecular mechanisms.This review focuses on optic nerve crush and glaucoma models,elucidating the mechanisms of optic nerve injury and neuron degeneration induced by glaucoma through single-cell transcriptomics,transcriptome analysis,and chip analysis.Research using the optic nerve crush model has shown that different retinal ganglion cell subtypes exhibit varying survival and regenerative capacities following injury.Single-cell RNA sequencing has identified multiple genes associated with retinal ganglion cell protection and regeneration,such as Gal,Ucn,and Anxa2.In glaucoma models,high-throughput sequencing has revealed transcriptomic changes in retinal ganglion cells under elevated intraocular pressure,identifying genes related to immune response,oxidative stress,and apoptosis.These genes are significantly upregulated early after optic nerve injury and may play key roles in neuroprotection and axon regeneration.Additionally,CRISPR-Cas9 screening and ATAC-seq analysis have identified key transcription factors that regulate retinal ganglion cell survival and axon regeneration,offering new potential targets for neurorepair strategies in glaucoma.In summary,single-cell transcriptomic technologies provide unprecedented insights into the molecular mechanisms underlying optic nerve injury,aiding in the identification of novel therapeutic targets.Future researchers should integrate advanced single-cell sequencing with multi-omics approaches to investigate cell-specific responses in retinal ganglion cell injury and regeneration.Furthermore,computational models and systems biology methods could help predict molecular pathways interactions,providing valuable guidance for clinical research on optic nerve regeneration and repair.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
Dear Editor,Dorsal pontine lesions may cause a variety of complex neuro-ophthalmic deficits,including horizontal gaze palsy(HGP),internuclear ophthalmoplegia,one-and-ahalf syndrome,abducens nerve palsy,skew deviation,...Dear Editor,Dorsal pontine lesions may cause a variety of complex neuro-ophthalmic deficits,including horizontal gaze palsy(HGP),internuclear ophthalmoplegia,one-and-ahalf syndrome,abducens nerve palsy,skew deviation,or any combination of these.Here we present a rare case of an adult patient who developed multiple complicated clinical manifestations after surgical removal of a pontine cavernous hemangioma(PCH).Our case highlights a single pontine lesion may involve complicated neural pathways and result in complicated symptoms and signs,in which abducens nerve palsy or skew deviation is easily missed when combined with HGP.展开更多
Peripheral nerve injury is a complex condition presenting significant clinical treatment challenges due to the limited regenerative capacity of peripheral nerves.Nerve conduits have been seen as a promising strategy t...Peripheral nerve injury is a complex condition presenting significant clinical treatment challenges due to the limited regenerative capacity of peripheral nerves.Nerve conduits have been seen as a promising strategy to overcome the shortage of other treatment options(e.g.,nerve graft).However,nerve regeneration occurs within a complex environment,and elaborate modulation is needed to meet repair requirements.The aim of this study was to investigate and explore a multifunctional nerve conduit with reactive oxygen species clearing,immune modulation to reshape the regenerative environment,and topographic cues and electrical signals to guide nerve growth.We developed an electroactive nerve guidance conduit composed of polylactic-glycolic acid and carbon nanotubes with an oriented structure using electrospinning and modified it with mussel-inspired polydopamine combining neurotrophin-3.The resulting nerve scaffold exhibited favorable orientation,electrical conductivity,and mechanical properties.Continuous release of neurotrophin-3 from the nerve conduit supported nerve regeneration throughout the repair process.In vitro assessments confirmed the cytocompatibility,reactive oxygen species scavenging,and immune regulation capabilities of the nerve scaffolds.In a rat sciatic nerve defect model,the nerve scaffolds effectively prevented muscle atrophy and promoted nerve regeneration and functional recovery over a 12-week period.These findings suggest that polydopamine-modified,electroactive,oriented nerve guidance conduits with multiple bioactive functions hold great promise for the repair of peripheral nerve injuries.展开更多
Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological prop...Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological properties and tissue specificity,highlighting its potential as a biomedical material for the repair of severe peripheral nerve injury;however,its role in modulating neuroinflammation post-peripheral nerve injury remains unknown.Here,we aimed to characterize the anti-inflammatory properties of porcine decellularized nerve matrix hydrogel and their underlying molecular mechanisms.Using peripheral nerve injury model rats treated with porcine decellularized nerve matrix hydrogel,we evaluated structural and functional recovery,macrophage phenotype alteration,specific cytokine expression,and changes in related signaling molecules in vivo.Similar parameters were evaluated in vitro using monocyte/macrophage cell lines stimulated with lipopolysaccharide and cultured on porcine decellularized nerve matrix hydrogel-coated plates in complete medium.These comprehensive analyses revealed that porcine decellularized nerve matrix hydrogel attenuated the activation of excessive inflammation at the early stage of peripheral nerve injury and increased the proportion of the M2 subtype in monocytes/macrophages.Additionally,porcine decellularized nerve matrix hydrogel negatively regulated the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB axis both in vivo and in vitro.Our findings suggest that the efficacious anti-inflammatory properties of porcine decellularized nerve matrix hydrogel induce M2 macrophage polarization via suppression of the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB pathway,providing new insights into the therapeutic mechanism of porcine decellularized nerve matrix hydrogel in peripheral nerve injury.展开更多
Traumatic axonal lesions of peripheral nerves disrupt neuronal connections with their targets,resulting in the loss of motor and sensory functions.Despite the peripheral nervous system’s capacity for axonal regrowth,...Traumatic axonal lesions of peripheral nerves disrupt neuronal connections with their targets,resulting in the loss of motor and sensory functions.Despite the peripheral nervous system’s capacity for axonal regrowth,this may lead to permanent impairements resulting in a loss of quality of life and a high socioeconomic burden.展开更多
Despite recent great progress in diagnosis and microsurgical repair, the prognosis in total brachial plexus-avulsion injury remains unfavorable.Insufficient number of donors and unreasonable use of donor nerves might ...Despite recent great progress in diagnosis and microsurgical repair, the prognosis in total brachial plexus-avulsion injury remains unfavorable.Insufficient number of donors and unreasonable use of donor nerves might be key factors. To identify an optimal treatment strategy for this condition, we conducted a retrospective review. Seventy-three patients with total brachial plexus avulsion injury were followed up for an average of 7.3 years. Our analysis demonstrated no significant difference in elbow-flexion recovery between phrenic nerve-transfer （25 cases）, phrenic nerve-graft （19 cases）, intercostal nerve （17 cases）, or contralateral C7-transfer （12 cases） groups. Restoration of shoulder function was attempted through anterior accessory nerve （27 cases）, posterior accessory nerve （10 cases）, intercostal nerve （5 cases）, or accessory ＋ intercostal nerve transfer （31 cases）. Accessory nerve ＋ intercostal nerve transfer was the most effective method. A significantly greater amount of elbow extension was observed in patients with intercostal nerve transfer （25 cases） than in those with contralateral C7 transfer （10 cases）. Recovery of median nerve function was noticeably better for those who received entire contralateral C7 transfer （33 cases） than for those who received partial contralateral C7 transfer （40 cases）. Wrist and finger extension were reconstructed by intercostal nerve transfer （31 cases）. Overall, the recommended surgical treatment for total brachial plexus-avulsion injury is phrenic nerve transfer for elbow flexion, accessory nerve ＋ intercostal nerve transfer for shoulder function, intercostal nerves transfer for elbow extension, entire contralateral C7 transfer for median nerve function, and intercostal nerve transfer for finger extension. The trial was registered at Clinical-Trials.gov （identifier： NCT03166033）.展开更多
Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the ...Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGCs). However, the use of tNGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGCs and compared the various features of these improved silk^(+) tNGCs with the tubes without holes(silk^(–) tNGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimization of the macroscopic holes silk^(+) tNGC approach containing macroscopic holes might result in improved grafting technology suitable for future clinical use.展开更多
Spinal cord injury is a severe neurological condition characterized by the permanent loss of nerve cell function and a failure in neural circuit reconstruction-key factors contributing to disability.Therefore,explorin...Spinal cord injury is a severe neurological condition characterized by the permanent loss of nerve cell function and a failure in neural circuit reconstruction-key factors contributing to disability.Therefore,exploring effective strategies to promote the repair and regeneration of nerve cells after spinal cord injury is crucial for optimizing patient prognosis.The purpose of this paper is to conduct an in-depth review of the pathological changes in nerve cells after spinal cord injury and to present the state of research on the role of exercise training in promoting the repair and regeneration of nerve cells after spinal cord injury.In terms of the intrinsic growth capacity of neurons,disruptions in the dynamic balance between growth cones and the cytoskeleton,the dysregulation of transcription factors,abnormal protein signaling transduction,and altered epigenetic modifications collectively hinder axonal regeneration.Additionally,the microenvironment of neurons undergoes a series of complex changes,initially manifesting as edema,which may be exacerbated by spinal cord ischemia-reperfusion injury,further increasing the extent of nerve cell damage.The abnormal proliferation of astrocytes leads to the formation of glial scars,creating a physical barrier to nerve regeneration.The inflammatory response triggered by the excessive activation of microglia negatively impacts the process of nerve repair.Non-invasive interventions involving exercise training have shown significant potential in promoting nerve repair as part of a comprehensive treatment strategy for spinal cord injury.Specifically,exercise training can reshape the growth cone and cytoskeletal structures of neurons,regulate transcription factor activity,modulate protein signaling pathways,and influence epigenetic modifications,thereby activating the intrinsic repair mechanisms of neurons.Moreover,exercise training can regulate the activation state of astrocytes,optimize the inflammatory response and metabolic processes,promote astrocyte polarization,enhance angiogenesis,reduce glial scar formation,and modulate the expression levels of nerve growth factors.It also effectively helps regulate microglial activation,promotes axonal regeneration,and improves phagocytic function,thereby optimizing the microenvironment for nerve repair.In terms of clinical translation,we summarize the preliminary results of new drug research and development efforts,the development of innovative devices,and the use of exercise training in promoting clinical advancements in nerve repair following spinal cord injury,while considering their limitations and future application prospects.In summary,this review systematically analyzes findings relating to the pathological changes occurring in nerve cells after spinal cord injury and emphasizes the critical role of exercise training in facilitating the repair and regeneration of nerve cells.This work is expected to provide new ideas and methods for the rehabilitation of patients with spinal cord injury.展开更多
The visual system of teleost fish grows continuously,which is a useful model for studying regeneration of the central nervous system.Glial cells are key for this process,but their contribution is still not well define...The visual system of teleost fish grows continuously,which is a useful model for studying regeneration of the central nervous system.Glial cells are key for this process,but their contribution is still not well defined.We followed oligodendrocytes in the visual system of adult zebrafish during regeneration of the optic nerve at 6,24,and 72 hours post-lesion and at 7 and 14 days post-lesion via the sox10:tagRFP transgenic line and confocal microscopy.To understand the changes that these oligodendrocytes undergo during regeneration,we used Sox2 immunohistochemistry,a stem cell marker involved in oligodendrocyte differentiation.We also used the Click-iT™ Plus TUNEL assay to study cell death and a BrdU assay to determine cell proliferation.Before optic nerve crush,sox10:tagRFP oligodendrocytes are located in the retina,in the optic nerve head,and through all the entire optic nerve.Sox2-positive cells are present in the peripheral germinal zone,the mature retina,and the optic nerve.After optic nerve crush,sox10:tagRFP cells disappeared from the optic nerve crush zone,suggesting that they died,although they were not TUNEL positive.Concomitantly,the number of Sox2-positive cells increased around the crushed area,the optic nerve head,and the retina.Then,between 24 hours post-lesion and 14 days post-lesion,double sox10:tagRFP/Sox2-positive cells were detected in the retina,optic nerve head,and whole optic nerve,together with a proliferation response at 72 hours post-lesion.Our results confirm that a degenerating process may occur prior to regeneration.First,sox10:tagRFP oligodendrocytes that surround the degenerated axons stop wrapping them,change their“myelinating oligodendrocyte”morphology to a“nonmyelinating oligodendrocyte”morphology,and die.Then,residual oligodendrocyte progenitor cells in the optic nerve and retina proliferate and differentiate for the purpose of remyelination.As new axons arise from the surviving retinal ganglion cells,new sox10:tagRFP oligodendrocytes arise from residual oligodendrocyte progenitor cells to guide,nourish and myelinate them.Thus,oligodendrocytes play an active role in zebrafish axon regeneration and remyelination.展开更多
Our recent study demonstrated that knockout of microRNA-301a attenuates migration and phagocytosis in macrophages.Considering that macrophages and Schwann cells synergistically clear the debris of degraded axons and m...Our recent study demonstrated that knockout of microRNA-301a attenuates migration and phagocytosis in macrophages.Considering that macrophages and Schwann cells synergistically clear the debris of degraded axons and myelin during Wallerian degeneration,which is a prerequisite for nerve regeneration,we hypothesized that microRNA-301a regulates Wallerian degeneration and nerve regeneration via impacts on Schwann cell migration and phagocytosis.Herein,we found low expression of microRNA-301a in intact sciatic nerves,with no impact of the microRNA-301a knockout on nerve structure and function.By contrast,we found significant upregulation of microRNA-301a in injured sciatic nerves.We established a sciatic nerve crush model in microRNA-301a knockout mice,which exhibited attenua9ted morphological and functional regeneration following sciatic nerve crush injury.The microRNA-301a knockout also led to significantly inhibited Wallerian degeneration in an in vivo sciatic nerve-transection model and in an in vitro nerve explant block model.Schwann cells with the microRNA-301a knockout showed inhibition of phagocytosis and migration,which was reversible under transfection with microRNA-301a mimics.Rescue experiments involving transfection of microRNA-301a-knockout Schwann cells with microRNA-301a mimics or treatment with the C-X-C motif receptor 4 inhibitor WZ811 indicated the mechanistic involvement of the Yin Yang 1/C-X-C motif receptor 4 pathway in the role of microRNA-301a.Combined with our previous findings in macrophages,we conclude that microRNA-301a plays a key role in peripheral nerve injury and repair by regulating the migratory and phagocytic capabilities of Schwann cells and macrophages via the Yin Yang 1/C-X-C motif receptor 4 pathway.展开更多
The gut microbiota:The human body is colonized by a diverse and complex microbial community–including bacteria,viruses,archaea,and unicellular eukaryotes–that plays a central role in human wellbeing.Indeed,microbiot...The gut microbiota:The human body is colonized by a diverse and complex microbial community–including bacteria,viruses,archaea,and unicellular eukaryotes–that plays a central role in human wellbeing.Indeed,microbiota is crucial for several functions,including host metabolism,physiology,maintenance of the intestinal epithelial integrity,nutrition,and immune function,earning it the designation of a“vital organ”(Guinane and Cotter,2013).展开更多
Tactile feedback is critical for human interaction with external information.Similarly,tactile feedback can enrich the user's sensations when using prosthesis.To explore a potential scheme for tactile feedback,thi...Tactile feedback is critical for human interaction with external information.Similarly,tactile feedback can enrich the user's sensations when using prosthesis.To explore a potential scheme for tactile feedback,this study applied a non-inva-sive Transcutaneous Electrical Nerve Stimulation(TENS)to elicit tactile sensations in the hand,which involved median nerve,ulnar nerve,and radial nerve.Ten able-bodied subjects(8 males,2 females)were recruited to participate in the study.An array of 4×2 electrodes was positioned on the medial aspect of the brachii muscle's short head in the upper arm,which is in proximity to the median nerve,ulnar nerve,and radial nerve.Different electrode pairs were randomly selected to elicit distinct sensations at various positions on the hand,and the subjects reported the sensory areas.Then,the sensory areas and sensory thresholds were confirmed through psychophysical methods.According to the experimental results,tactile sensations were elicited at different locations on the subjects'hand through TENS of different electrode pairs.All subjects reported extensive and detailed sensory areas in the fingers,palm,and dorsum,corresponding to the sensory innervation areas of different nerves.The study effectively demonstrated the ability of TENS in evoking tactile feedback in the hand,paving the way for future optimization and development of prosthetic hands.展开更多
1Introduction A 25-year-old woman presented with a 3-month history of otalgia and aural fullness in the left ear,without associated otological or systemic symptoms.Her medical history was unremarkable,and she denied a...1Introduction A 25-year-old woman presented with a 3-month history of otalgia and aural fullness in the left ear,without associated otological or systemic symptoms.Her medical history was unremarkable,and she denied any history of hepatitis,hypertension,diabetes,cardiovascular disease,or other significant conditions.The patient was diagnosed with external auditory canal cholesteatoma and subsequently underwent canalplasty under general anesthesia.Routine anesthetic drugs,including 2%lidocaine,dexamethasone,propofol,sufentanil,rocuronium bromide,ondansetron,flurbiprofen axetil,neostigmine,and atropine,were used during surgery and anesthesia recovery.No significant events were noted,and the patient experienced only a blood loss of 10 mL.展开更多
Peripheral nerve injury is a serious disease and its repair is challenging. A cable-style autologous graft is the gold standard for repairing long peripheral nerve defects; however, ensuring that the minimum number of...Peripheral nerve injury is a serious disease and its repair is challenging. A cable-style autologous graft is the gold standard for repairing long peripheral nerve defects; however, ensuring that the minimum number of transplanted nerve attains maximum therapeutic effect remains poorly understood. In this study, a rat model of common peroneal nerve defect was established by resecting a 10-mm long right common peroneal nerve. Rats receiving transplantation of the common peroneal nerve in situ were designated as the in situ graft group. Ipsilateral sural nerves（10–30 mm long） were resected to establish the one sural nerve graft group, two sural nerves cable-style nerve graft group and three sural nerves cable-style nerve graft group. Each bundle of the peroneal nerve was 10 mm long. To reduce the barrier effect due to invasion by surrounding tissue and connective-tissue overgrowth between neural stumps, small gap sleeve suture was used in both proximal and distal terminals to allow repair of the injured common peroneal nerve. At three months postoperatively, recovery of nerve function and morphology was observed using osmium tetroxide staining and functional detection. The results showed that the number of regenerated nerve fibers, common peroneal nerve function index, motor nerve conduction velocity, recovery of myodynamia, and wet weight ratios of tibialis anterior muscle were not significantly different among the one sural nerve graft group, two sural nerves cable-style nerve graft group, and three sural nerves cable-style nerve graft group. These data suggest that the repair effect achieved using one sural nerve graft with a lower number of nerve fibers is the same as that achieved using the two sural nerves cable-style nerve graft and three sural nerves cable-style nerve graft. This indicates that according to the ‘multiple amplification＇ phenomenon, one small nerve graft can provide a good therapeutic effect for a large peripheral nerve defect.展开更多
Autografting is the gold standard for surgical repair of nerve defects>5 mm in length;however,autografting is associated with potential complications at the nerve donor site.As an alternative,nerve guidance conduit...Autografting is the gold standard for surgical repair of nerve defects>5 mm in length;however,autografting is associated with potential complications at the nerve donor site.As an alternative,nerve guidance conduits may be used.The ideal conduit should be flexible,resistant to kinks and lumen collapse,and provide physical cues to guide nerve regeneration.We designed a novel flexible conduit using electrospinning technology to create fibers on the innermost surface of the nerve guidance conduit and employed melt spinning to align them.Subsequently,we prepared disordered electrospun fibers outside the aligned fibers and helical melt-spun fibers on the outer wall of the electrospun fiber lumen.The presence of aligned fibers on the inner surface can promote the extension of nerve cells along the fibers.The helical melt-spun fibers on the outer surface can enhance resistance to kinking and compression and provide stability.Our novel conduit promoted nerve regeneration and functional recovery in a rat sciatic nerve defect model,suggesting that it has potential for clinical use in human nerve injuries.展开更多
Human acellular nerve allografts have a wide range of donor origin and can effectively avoid nerve injury in the donor area. Very little is known about one-stage reconstruction of digital nerve defects. The present st...Human acellular nerve allografts have a wide range of donor origin and can effectively avoid nerve injury in the donor area. Very little is known about one-stage reconstruction of digital nerve defects. The present study observed the feasibility and effectiveness of human acellular nerve allograft in the reconstruction of 〈 5-cm digital nerve defects within 6 hours after injury. A total of 15 cases of nerve injury, combined with nerve defects in 18 digits from the Department of Emergency were enrolled in this study. After dehridement, digital nerves were reconstructed using human acellular nerve allografts. The patients were followed up for 6-24 months after reconstruction. Mackinnon-Dellon static two-point discrimination results showed excellent and good rates of 89%. Semmes-Weinstein monofilament test demonstrated that light touch was normal, with an obvious improvement rate of 78%. These findings confirmed that human acellular nerve allograft for one-stage reconstruction of digital nerve defect after hand injury is feasible, which provides a novel trend for peripheral nerve reconstruction.展开更多
Demyelination and remyelination have been major focal points in the study of peripheral nerve regeneration following peripheral nerve injury.Notably,the gene regulatory network of regenerated myelin differs from that ...Demyelination and remyelination have been major focal points in the study of peripheral nerve regeneration following peripheral nerve injury.Notably,the gene regulatory network of regenerated myelin differs from that of native myelin.Silencing of enhancer of zeste homolog 2(EZH2)hinders the differentiation,maturation,and myelination of Schwann cells in vitro.To further determine the role of EZH2 in myelination and recovery post-peripheral nerve injury,conditional knockout mice lacking Ezh2 in Schwann cells(Ezh2^(fl/fl);Dhh-Cre and Ezh2^(fl/fl);Mpz-Cre)were generated.Our results show that a significant proportion of axons in the sciatic nerve of Ezh2-depleted mice remain unmyelinated.This highlights the crucial role of Ezh2 in initiating Schwann cell myelination.Furthermore,we observed that 21 days after inducing a sciatic nerve crush injury in these mice,most axons had remyelinated at the injury site in the control nerve,while Ezh2^(fl/fl);Mpz-Cre mice had significantly fewer remyelinated axons compared with their wild-type littermates.This suggests that the absence of Ezh2 in Schwann cells impairs myelin formation and remyelination.In conclusion,EZH2 has emerged as a pivotal regulatory factor in the process of demyelination and myelin regeneration following peripheral nerve injury.Modulating EZH2 activity during these processes may offer a promising therapeutic target for the treatment of peripheral nerve injuries.展开更多
Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong disability.Currently,there are no FDA-approved therapies a...Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong disability.Currently,there are no FDA-approved therapies available to promote nerve regeneration.Tacrolimus accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve surgery.The authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug exposure.Tacrolimus is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 days.Size and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 days into biocompatible byproducts.Tacrolimus released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic delivery.Given its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.展开更多
基金the support from Base for Interdisciplinary Innovative Talent Training,Shanghai Jiao Tong UniversityYouth Science and Technology Innovation Studio of Shanghai Jiao Tong University School of Medicine。
文摘Neural injuries can cause considerable functional impairments,and both central and peripheral nervous systems have limited regenerative capacity.The existing conventional pharmacological treatments in clinical practice show poor targeting,rapid drug clearance from the circulatory system,and low therapeutic efficiency.Therefore,in this review,we have first described the mechanisms underlying nerve regeneration,characterized the biomaterials used for drug delivery to facilitate nerve regeneration,and highlighted the functionalization strategies used for such drug-delivery systems.These systems mainly use natural and synthetic polymers,inorganic materials,and hybrid systems with advanced drug-delivery abilities,including nanoparticles,hydrogels,and scaffoldbased systems.Then,we focused on comparing the types of drug-delivery systems for neural regeneration as well as the mechanisms and challenges associated with targeted delivery of drugs to facilitate neural regeneration.Finally,we have summarized the clinical application research and limitations of targeted delivery of these drugs.These biomaterials and drug-delivery systems can provide mechanical support,sustained release of bioactive molecules,and enhanced intercellular contact,ultimately reducing cell apoptosis and enhancing functional recovery.Nevertheless,immune reactions,degradation regulation,and clinical translations remain major unresolved challenges.Future studies should focus on optimizing biomaterial properties,refining delivery precision,and overcoming translational barriers to advance these technologies toward clinical applications.
基金supported by the National Natural Science Foundation of China,Nos.82471123,82171053the Jilin Province Special Project for Talent in Medical and Health Sciences,No.2024WSXK-E01the Natural Science Foundation of Jilin Province,YDZJ202501ZYTS318(all to GL).
文摘Retinal ganglion cells,a crucial component of the central nervous system,are often affected by irreversible visual impairment due to various conditions,including trauma,tumors,ischemia,and glaucoma.Studies have shown that the optic nerve crush model and glaucoma model are commonly used to study retinal ganglion cell injury.While these models differ in their mechanisms,both ultimately result in retinal ganglion cell injury.With advancements in high-throughput technologies,techniques such as microarray analysis,RNA sequencing,and single-cell RNA sequencing have been widely applied to characterize the transcriptomic profiles of retinal ganglion cell injury,revealing underlying molecular mechanisms.This review focuses on optic nerve crush and glaucoma models,elucidating the mechanisms of optic nerve injury and neuron degeneration induced by glaucoma through single-cell transcriptomics,transcriptome analysis,and chip analysis.Research using the optic nerve crush model has shown that different retinal ganglion cell subtypes exhibit varying survival and regenerative capacities following injury.Single-cell RNA sequencing has identified multiple genes associated with retinal ganglion cell protection and regeneration,such as Gal,Ucn,and Anxa2.In glaucoma models,high-throughput sequencing has revealed transcriptomic changes in retinal ganglion cells under elevated intraocular pressure,identifying genes related to immune response,oxidative stress,and apoptosis.These genes are significantly upregulated early after optic nerve injury and may play key roles in neuroprotection and axon regeneration.Additionally,CRISPR-Cas9 screening and ATAC-seq analysis have identified key transcription factors that regulate retinal ganglion cell survival and axon regeneration,offering new potential targets for neurorepair strategies in glaucoma.In summary,single-cell transcriptomic technologies provide unprecedented insights into the molecular mechanisms underlying optic nerve injury,aiding in the identification of novel therapeutic targets.Future researchers should integrate advanced single-cell sequencing with multi-omics approaches to investigate cell-specific responses in retinal ganglion cell injury and regeneration.Furthermore,computational models and systems biology methods could help predict molecular pathways interactions,providing valuable guidance for clinical research on optic nerve regeneration and repair.
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.
文摘Dear Editor,Dorsal pontine lesions may cause a variety of complex neuro-ophthalmic deficits,including horizontal gaze palsy(HGP),internuclear ophthalmoplegia,one-and-ahalf syndrome,abducens nerve palsy,skew deviation,or any combination of these.Here we present a rare case of an adult patient who developed multiple complicated clinical manifestations after surgical removal of a pontine cavernous hemangioma(PCH).Our case highlights a single pontine lesion may involve complicated neural pathways and result in complicated symptoms and signs,in which abducens nerve palsy or skew deviation is easily missed when combined with HGP.
基金supported by the National Key R&D Program of China,No.2022YFC3006200(to YW)the Natural Science Foundation of Beijing,No.7232190(to YW)+1 种基金Zhejiang Province Medical and Health Technology Plan Project,Nos.2022020506(to XW),2024KY1612(to JX),2024KY1615(to MY)Ningbo Clinical Research Center for Orthopedics and Sports Rehabilitation,No.2024L004(to XW).
文摘Peripheral nerve injury is a complex condition presenting significant clinical treatment challenges due to the limited regenerative capacity of peripheral nerves.Nerve conduits have been seen as a promising strategy to overcome the shortage of other treatment options(e.g.,nerve graft).However,nerve regeneration occurs within a complex environment,and elaborate modulation is needed to meet repair requirements.The aim of this study was to investigate and explore a multifunctional nerve conduit with reactive oxygen species clearing,immune modulation to reshape the regenerative environment,and topographic cues and electrical signals to guide nerve growth.We developed an electroactive nerve guidance conduit composed of polylactic-glycolic acid and carbon nanotubes with an oriented structure using electrospinning and modified it with mussel-inspired polydopamine combining neurotrophin-3.The resulting nerve scaffold exhibited favorable orientation,electrical conductivity,and mechanical properties.Continuous release of neurotrophin-3 from the nerve conduit supported nerve regeneration throughout the repair process.In vitro assessments confirmed the cytocompatibility,reactive oxygen species scavenging,and immune regulation capabilities of the nerve scaffolds.In a rat sciatic nerve defect model,the nerve scaffolds effectively prevented muscle atrophy and promoted nerve regeneration and functional recovery over a 12-week period.These findings suggest that polydopamine-modified,electroactive,oriented nerve guidance conduits with multiple bioactive functions hold great promise for the repair of peripheral nerve injuries.
基金supported by the Shenzhen Hong Kong Joint Funding Project,No.SGDX20230116093645007(to LY)the Shenzhen Science and Technology Innovation Committee International Cooperation Project,No.GJHZ20200731095608025(to LY)+7 种基金Shenzhen Development and Reform Commission’s Intelligent Diagnosis,Treatment and Prevention of Adolescent Spinal Health Public Service Platform,No.S2002Q84500835(to LY)Shenzhen Medical Research Fund,No.B2303005(to LY)Team-based Medical Science Research Program,No.2024YZZ02(to LY)Zhejiang Provincial Natural Science Foundation of China,No.LWQ20H170001(to RL)Basic Research Project of Shenzhen Science and Technology from Shenzhen Science and Technology Innovation Commission,No.JCYJ20210324103010029(to BY)Shenzhen Second People’s Hospital Clinical Research Fund of Guangdong Province High-level Hospital Construction Project,Nos.2023yjlcyj029(to BY),2023yjlcyj021(to LL)Guangdong Basic and Applied Basic Research Foundation,No.2022A1515110679(to LL)China Postdoctoral Science Foundation,No.2022M722203(to GL).
文摘Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological properties and tissue specificity,highlighting its potential as a biomedical material for the repair of severe peripheral nerve injury;however,its role in modulating neuroinflammation post-peripheral nerve injury remains unknown.Here,we aimed to characterize the anti-inflammatory properties of porcine decellularized nerve matrix hydrogel and their underlying molecular mechanisms.Using peripheral nerve injury model rats treated with porcine decellularized nerve matrix hydrogel,we evaluated structural and functional recovery,macrophage phenotype alteration,specific cytokine expression,and changes in related signaling molecules in vivo.Similar parameters were evaluated in vitro using monocyte/macrophage cell lines stimulated with lipopolysaccharide and cultured on porcine decellularized nerve matrix hydrogel-coated plates in complete medium.These comprehensive analyses revealed that porcine decellularized nerve matrix hydrogel attenuated the activation of excessive inflammation at the early stage of peripheral nerve injury and increased the proportion of the M2 subtype in monocytes/macrophages.Additionally,porcine decellularized nerve matrix hydrogel negatively regulated the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB axis both in vivo and in vitro.Our findings suggest that the efficacious anti-inflammatory properties of porcine decellularized nerve matrix hydrogel induce M2 macrophage polarization via suppression of the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB pathway,providing new insights into the therapeutic mechanism of porcine decellularized nerve matrix hydrogel in peripheral nerve injury.
文摘Traumatic axonal lesions of peripheral nerves disrupt neuronal connections with their targets,resulting in the loss of motor and sensory functions.Despite the peripheral nervous system’s capacity for axonal regrowth,this may lead to permanent impairements resulting in a loss of quality of life and a high socioeconomic burden.
基金supported by the National Natural Science Foundation of China,No.H0605/81501871
文摘Despite recent great progress in diagnosis and microsurgical repair, the prognosis in total brachial plexus-avulsion injury remains unfavorable.Insufficient number of donors and unreasonable use of donor nerves might be key factors. To identify an optimal treatment strategy for this condition, we conducted a retrospective review. Seventy-three patients with total brachial plexus avulsion injury were followed up for an average of 7.3 years. Our analysis demonstrated no significant difference in elbow-flexion recovery between phrenic nerve-transfer （25 cases）, phrenic nerve-graft （19 cases）, intercostal nerve （17 cases）, or contralateral C7-transfer （12 cases） groups. Restoration of shoulder function was attempted through anterior accessory nerve （27 cases）, posterior accessory nerve （10 cases）, intercostal nerve （5 cases）, or accessory ＋ intercostal nerve transfer （31 cases）. Accessory nerve ＋ intercostal nerve transfer was the most effective method. A significantly greater amount of elbow extension was observed in patients with intercostal nerve transfer （25 cases） than in those with contralateral C7 transfer （10 cases）. Recovery of median nerve function was noticeably better for those who received entire contralateral C7 transfer （33 cases） than for those who received partial contralateral C7 transfer （40 cases）. Wrist and finger extension were reconstructed by intercostal nerve transfer （31 cases）. Overall, the recommended surgical treatment for total brachial plexus-avulsion injury is phrenic nerve transfer for elbow flexion, accessory nerve ＋ intercostal nerve transfer for shoulder function, intercostal nerves transfer for elbow extension, entire contralateral C7 transfer for median nerve function, and intercostal nerve transfer for finger extension. The trial was registered at Clinical-Trials.gov （identifier： NCT03166033）.
基金supported by the Lorenz B?hler Fonds,#2/19 (obtained by the Neuroregeneration Group,Ludwig Boltzmann Institute for Traumatology)the City of Vienna project ImmunTissue,MA23#30-11 (obtained by the Department Life Science Engineering,University of Applied Sciences Technikum Wien)。
文摘Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGCs). However, the use of tNGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGCs and compared the various features of these improved silk^(+) tNGCs with the tubes without holes(silk^(–) tNGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimization of the macroscopic holes silk^(+) tNGC approach containing macroscopic holes might result in improved grafting technology suitable for future clinical use.
基金supported by the National Natural Science Foundation of China,No.81641048Research Project of Yan’an University,No.2023JBZR-011(both to LZ).
文摘Spinal cord injury is a severe neurological condition characterized by the permanent loss of nerve cell function and a failure in neural circuit reconstruction-key factors contributing to disability.Therefore,exploring effective strategies to promote the repair and regeneration of nerve cells after spinal cord injury is crucial for optimizing patient prognosis.The purpose of this paper is to conduct an in-depth review of the pathological changes in nerve cells after spinal cord injury and to present the state of research on the role of exercise training in promoting the repair and regeneration of nerve cells after spinal cord injury.In terms of the intrinsic growth capacity of neurons,disruptions in the dynamic balance between growth cones and the cytoskeleton,the dysregulation of transcription factors,abnormal protein signaling transduction,and altered epigenetic modifications collectively hinder axonal regeneration.Additionally,the microenvironment of neurons undergoes a series of complex changes,initially manifesting as edema,which may be exacerbated by spinal cord ischemia-reperfusion injury,further increasing the extent of nerve cell damage.The abnormal proliferation of astrocytes leads to the formation of glial scars,creating a physical barrier to nerve regeneration.The inflammatory response triggered by the excessive activation of microglia negatively impacts the process of nerve repair.Non-invasive interventions involving exercise training have shown significant potential in promoting nerve repair as part of a comprehensive treatment strategy for spinal cord injury.Specifically,exercise training can reshape the growth cone and cytoskeletal structures of neurons,regulate transcription factor activity,modulate protein signaling pathways,and influence epigenetic modifications,thereby activating the intrinsic repair mechanisms of neurons.Moreover,exercise training can regulate the activation state of astrocytes,optimize the inflammatory response and metabolic processes,promote astrocyte polarization,enhance angiogenesis,reduce glial scar formation,and modulate the expression levels of nerve growth factors.It also effectively helps regulate microglial activation,promotes axonal regeneration,and improves phagocytic function,thereby optimizing the microenvironment for nerve repair.In terms of clinical translation,we summarize the preliminary results of new drug research and development efforts,the development of innovative devices,and the use of exercise training in promoting clinical advancements in nerve repair following spinal cord injury,while considering their limitations and future application prospects.In summary,this review systematically analyzes findings relating to the pathological changes occurring in nerve cells after spinal cord injury and emphasizes the critical role of exercise training in facilitating the repair and regeneration of nerve cells.This work is expected to provide new ideas and methods for the rehabilitation of patients with spinal cord injury.
基金supported by the Lanzadera TCUE and C2 program(Universidad de Salamanca)(to ASL)the Spanish National Research Council(CSIC)funded by the Junta de Castilla y León and co-financed by the European Regional Development Fund(ERDF“Europe drives our growth”):Internationalization Project“CL-EI-2021-08-IBFG Unit of Excellence”,Grant(PID2022-138478OA-100)funded by MICIU/AEI/10.13039/501100011033 and,by FEDER,UE(to MGM)+3 种基金Junta de Castilla y León(SA225P23)Gerencia Regional de Salud(2701/A1/2023)(to AV)the Plan Especial Grado Medicina(USAL)(to CPM)a Ramón y Cajal researcher:Grant RYC2021-033684-I funded by MICIU/AEI/10.13039/501100011033 and,by European Union NextGenerationEU/PRTR.
文摘The visual system of teleost fish grows continuously,which is a useful model for studying regeneration of the central nervous system.Glial cells are key for this process,but their contribution is still not well defined.We followed oligodendrocytes in the visual system of adult zebrafish during regeneration of the optic nerve at 6,24,and 72 hours post-lesion and at 7 and 14 days post-lesion via the sox10:tagRFP transgenic line and confocal microscopy.To understand the changes that these oligodendrocytes undergo during regeneration,we used Sox2 immunohistochemistry,a stem cell marker involved in oligodendrocyte differentiation.We also used the Click-iT™ Plus TUNEL assay to study cell death and a BrdU assay to determine cell proliferation.Before optic nerve crush,sox10:tagRFP oligodendrocytes are located in the retina,in the optic nerve head,and through all the entire optic nerve.Sox2-positive cells are present in the peripheral germinal zone,the mature retina,and the optic nerve.After optic nerve crush,sox10:tagRFP cells disappeared from the optic nerve crush zone,suggesting that they died,although they were not TUNEL positive.Concomitantly,the number of Sox2-positive cells increased around the crushed area,the optic nerve head,and the retina.Then,between 24 hours post-lesion and 14 days post-lesion,double sox10:tagRFP/Sox2-positive cells were detected in the retina,optic nerve head,and whole optic nerve,together with a proliferation response at 72 hours post-lesion.Our results confirm that a degenerating process may occur prior to regeneration.First,sox10:tagRFP oligodendrocytes that surround the degenerated axons stop wrapping them,change their“myelinating oligodendrocyte”morphology to a“nonmyelinating oligodendrocyte”morphology,and die.Then,residual oligodendrocyte progenitor cells in the optic nerve and retina proliferate and differentiate for the purpose of remyelination.As new axons arise from the surviving retinal ganglion cells,new sox10:tagRFP oligodendrocytes arise from residual oligodendrocyte progenitor cells to guide,nourish and myelinate them.Thus,oligodendrocytes play an active role in zebrafish axon regeneration and remyelination.
基金supported by the National Natural Science Foundation of China,No.82071386(to JG).
文摘Our recent study demonstrated that knockout of microRNA-301a attenuates migration and phagocytosis in macrophages.Considering that macrophages and Schwann cells synergistically clear the debris of degraded axons and myelin during Wallerian degeneration,which is a prerequisite for nerve regeneration,we hypothesized that microRNA-301a regulates Wallerian degeneration and nerve regeneration via impacts on Schwann cell migration and phagocytosis.Herein,we found low expression of microRNA-301a in intact sciatic nerves,with no impact of the microRNA-301a knockout on nerve structure and function.By contrast,we found significant upregulation of microRNA-301a in injured sciatic nerves.We established a sciatic nerve crush model in microRNA-301a knockout mice,which exhibited attenua9ted morphological and functional regeneration following sciatic nerve crush injury.The microRNA-301a knockout also led to significantly inhibited Wallerian degeneration in an in vivo sciatic nerve-transection model and in an in vitro nerve explant block model.Schwann cells with the microRNA-301a knockout showed inhibition of phagocytosis and migration,which was reversible under transfection with microRNA-301a mimics.Rescue experiments involving transfection of microRNA-301a-knockout Schwann cells with microRNA-301a mimics or treatment with the C-X-C motif receptor 4 inhibitor WZ811 indicated the mechanistic involvement of the Yin Yang 1/C-X-C motif receptor 4 pathway in the role of microRNA-301a.Combined with our previous findings in macrophages,we conclude that microRNA-301a plays a key role in peripheral nerve injury and repair by regulating the migratory and phagocytic capabilities of Schwann cells and macrophages via the Yin Yang 1/C-X-C motif receptor 4 pathway.
基金supported by the European Union-Next Generation EU,Mission 4 Component 1,Project Title:“Gut and Neuro Muscular system:investigating the impact of microbiota on nerve regeneration and muscle reinnervation after peripheral nerve injury”,CUP D53D23007770006,MUR:20227YB93W,to GR。
文摘The gut microbiota:The human body is colonized by a diverse and complex microbial community–including bacteria,viruses,archaea,and unicellular eukaryotes–that plays a central role in human wellbeing.Indeed,microbiota is crucial for several functions,including host metabolism,physiology,maintenance of the intestinal epithelial integrity,nutrition,and immune function,earning it the designation of a“vital organ”(Guinane and Cotter,2013).
基金National Natural Science Foundation of China(Grant No.52525504)Emerging Frontiers Cultivation Program of Tianjin University Interdisciplinary Center.
文摘Tactile feedback is critical for human interaction with external information.Similarly,tactile feedback can enrich the user's sensations when using prosthesis.To explore a potential scheme for tactile feedback,this study applied a non-inva-sive Transcutaneous Electrical Nerve Stimulation(TENS)to elicit tactile sensations in the hand,which involved median nerve,ulnar nerve,and radial nerve.Ten able-bodied subjects(8 males,2 females)were recruited to participate in the study.An array of 4×2 electrodes was positioned on the medial aspect of the brachii muscle's short head in the upper arm,which is in proximity to the median nerve,ulnar nerve,and radial nerve.Different electrode pairs were randomly selected to elicit distinct sensations at various positions on the hand,and the subjects reported the sensory areas.Then,the sensory areas and sensory thresholds were confirmed through psychophysical methods.According to the experimental results,tactile sensations were elicited at different locations on the subjects'hand through TENS of different electrode pairs.All subjects reported extensive and detailed sensory areas in the fingers,palm,and dorsum,corresponding to the sensory innervation areas of different nerves.The study effectively demonstrated the ability of TENS in evoking tactile feedback in the hand,paving the way for future optimization and development of prosthetic hands.
基金supported by grants from Young Scientists Fund of the National Natural Science Foundation of China(grant number.82301295).
文摘1Introduction A 25-year-old woman presented with a 3-month history of otalgia and aural fullness in the left ear,without associated otological or systemic symptoms.Her medical history was unremarkable,and she denied any history of hepatitis,hypertension,diabetes,cardiovascular disease,or other significant conditions.The patient was diagnosed with external auditory canal cholesteatoma and subsequently underwent canalplasty under general anesthesia.Routine anesthetic drugs,including 2%lidocaine,dexamethasone,propofol,sufentanil,rocuronium bromide,ondansetron,flurbiprofen axetil,neostigmine,and atropine,were used during surgery and anesthesia recovery.No significant events were noted,and the patient experienced only a blood loss of 10 mL.
基金supported by the National Basic Research Program of China(973 Program),No.2014CB542200a grant from the Ministry of Education Innovation Team,No.IRT1201+2 种基金the National Natural Science Foundation of China,No.31271284,31171150,81171146,30971526,31100860,31040043,31640045,31671246a grant from the Educational Ministry New Century Excellent Talents Support Project in China,No.BMU20110270a grant from the National Key Research and Development Program in China,No.2016YFC1101604
文摘Peripheral nerve injury is a serious disease and its repair is challenging. A cable-style autologous graft is the gold standard for repairing long peripheral nerve defects; however, ensuring that the minimum number of transplanted nerve attains maximum therapeutic effect remains poorly understood. In this study, a rat model of common peroneal nerve defect was established by resecting a 10-mm long right common peroneal nerve. Rats receiving transplantation of the common peroneal nerve in situ were designated as the in situ graft group. Ipsilateral sural nerves（10–30 mm long） were resected to establish the one sural nerve graft group, two sural nerves cable-style nerve graft group and three sural nerves cable-style nerve graft group. Each bundle of the peroneal nerve was 10 mm long. To reduce the barrier effect due to invasion by surrounding tissue and connective-tissue overgrowth between neural stumps, small gap sleeve suture was used in both proximal and distal terminals to allow repair of the injured common peroneal nerve. At three months postoperatively, recovery of nerve function and morphology was observed using osmium tetroxide staining and functional detection. The results showed that the number of regenerated nerve fibers, common peroneal nerve function index, motor nerve conduction velocity, recovery of myodynamia, and wet weight ratios of tibialis anterior muscle were not significantly different among the one sural nerve graft group, two sural nerves cable-style nerve graft group, and three sural nerves cable-style nerve graft group. These data suggest that the repair effect achieved using one sural nerve graft with a lower number of nerve fibers is the same as that achieved using the two sural nerves cable-style nerve graft and three sural nerves cable-style nerve graft. This indicates that according to the ‘multiple amplification＇ phenomenon, one small nerve graft can provide a good therapeutic effect for a large peripheral nerve defect.
基金supported by the National Natural Science Foundation of China,No.82202718the Natural Science Foundation of Beijing,No.L212050the China Postdoctoral Science Foundation,Nos.2019M664007,2021T140793(all to ZL)。
文摘Autografting is the gold standard for surgical repair of nerve defects>5 mm in length;however,autografting is associated with potential complications at the nerve donor site.As an alternative,nerve guidance conduits may be used.The ideal conduit should be flexible,resistant to kinks and lumen collapse,and provide physical cues to guide nerve regeneration.We designed a novel flexible conduit using electrospinning technology to create fibers on the innermost surface of the nerve guidance conduit and employed melt spinning to align them.Subsequently,we prepared disordered electrospun fibers outside the aligned fibers and helical melt-spun fibers on the outer wall of the electrospun fiber lumen.The presence of aligned fibers on the inner surface can promote the extension of nerve cells along the fibers.The helical melt-spun fibers on the outer surface can enhance resistance to kinking and compression and provide stability.Our novel conduit promoted nerve regeneration and functional recovery in a rat sciatic nerve defect model,suggesting that it has potential for clinical use in human nerve injuries.
基金supported by grants from the National Program on Key Basic Research Project of China(973 Program),No.2014CB542200
文摘Human acellular nerve allografts have a wide range of donor origin and can effectively avoid nerve injury in the donor area. Very little is known about one-stage reconstruction of digital nerve defects. The present study observed the feasibility and effectiveness of human acellular nerve allograft in the reconstruction of 〈 5-cm digital nerve defects within 6 hours after injury. A total of 15 cases of nerve injury, combined with nerve defects in 18 digits from the Department of Emergency were enrolled in this study. After dehridement, digital nerves were reconstructed using human acellular nerve allografts. The patients were followed up for 6-24 months after reconstruction. Mackinnon-Dellon static two-point discrimination results showed excellent and good rates of 89%. Semmes-Weinstein monofilament test demonstrated that light touch was normal, with an obvious improvement rate of 78%. These findings confirmed that human acellular nerve allograft for one-stage reconstruction of digital nerve defect after hand injury is feasible, which provides a novel trend for peripheral nerve reconstruction.
基金financially supported by the National Natural Science Foundation of China,Nos.82172104(to CX),81873767(to HZ)a grant from Jiangsu Provincial Research Hospital,Nos.YJXYY202204(to HZ),YJXYY202204-ZD04(to HZ)+5 种基金a grant from Jiangsu Provincial Key Medical CenterJiangsu Provincial Medical Innovation Center,No.CXZX202212Jiangsu Provincial Medical Key Discipline,No.ZDXK202240the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)Technology Project of Nantong,No.MS22022008(to HZ)Postgraduate Research&Practice Innovation Program of Jiangsu Province,No.SJCX21_1457(to WW)。
文摘Demyelination and remyelination have been major focal points in the study of peripheral nerve regeneration following peripheral nerve injury.Notably,the gene regulatory network of regenerated myelin differs from that of native myelin.Silencing of enhancer of zeste homolog 2(EZH2)hinders the differentiation,maturation,and myelination of Schwann cells in vitro.To further determine the role of EZH2 in myelination and recovery post-peripheral nerve injury,conditional knockout mice lacking Ezh2 in Schwann cells(Ezh2^(fl/fl);Dhh-Cre and Ezh2^(fl/fl);Mpz-Cre)were generated.Our results show that a significant proportion of axons in the sciatic nerve of Ezh2-depleted mice remain unmyelinated.This highlights the crucial role of Ezh2 in initiating Schwann cell myelination.Furthermore,we observed that 21 days after inducing a sciatic nerve crush injury in these mice,most axons had remyelinated at the injury site in the control nerve,while Ezh2^(fl/fl);Mpz-Cre mice had significantly fewer remyelinated axons compared with their wild-type littermates.This suggests that the absence of Ezh2 in Schwann cells impairs myelin formation and remyelination.In conclusion,EZH2 has emerged as a pivotal regulatory factor in the process of demyelination and myelin regeneration following peripheral nerve injury.Modulating EZH2 activity during these processes may offer a promising therapeutic target for the treatment of peripheral nerve injuries.
基金supported by the German Research Foundation(DA 2255/1-1to SCD)+4 种基金a SickKids Research Training Competition(RESTRACOMP)Graduate Scholarship(to KJWS)an Ontario Graduate Scholarship(to KJWS)a grant from Natural Sciences and Engineering Research Council of Canada(NSERC)(to KJWS)a Kickstarter grant from the Institute of Biomedical Engineering(BME)at the University of Toronto(to KJWS)the Abe Frank Fund from the Riley’s Children Foundation(GHB)。
文摘Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong disability.Currently,there are no FDA-approved therapies available to promote nerve regeneration.Tacrolimus accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve surgery.The authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug exposure.Tacrolimus is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 days.Size and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 days into biocompatible byproducts.Tacrolimus released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic delivery.Given its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.
