Nerve Regeneration Research Articles

Intelligent design of nerve guidance conduits: An artificial intelligence‐driven fluid structure interaction study on modelling and optimization of nerve growth

AbstractNerve guidance conduits (NGCs) have been shown to be effective in promoting nerve regeneration in a variety of clinical applications, including nerve defects resulting from a trauma or surgery. By providing a conducive environment for nerve growth, NGCs can help to restore function in nerve‐damaged patients. Challenges include limited repair length, difficulty replicating natural nerve, and rapid substance degradation affecting neurotrophic factor delivery. Considering these issues with mass transfer and fluid structure interaction (FSI) emphasizes the need for enhancing nerve regeneration efficiency. To facilitate nerve growth and deliver appropriate amount of growth factors, these conduits need to be designed with specific topological, mechanical, and biological properties. Additionally, considerations must be given to functional mass transfer FSI design. An intelligent NGC design is proposed as an evaluation‐optimization and AI‐based method. It is found that design parameters significantly impact the physical properties being optimized, including hydraulic pressure, porosity, diffusivity, water absorption, and maximum stress. The mathematical surrogate model obtained from data‐based modelling is used for artificial intelligence (AI) optimization algorithms, differential evolution (DE), and non‐dominated sorting genetic algorithm II (NSGA‐II). It is revealed that both DE and NSGA algorithms generate nearly identical solutions, ensuring the robustness of ML optimization. Our results show that NGC with the thickness of 750 μm results in more than 170% augmentation of porosity. Moreover, at a constant ovality, increasing the channel thickness results in more than 39.2% augmentation of the maximum stress. The accurate forecasting of physical characteristics on NGC regarding nerve growth factors enables a hopeful outlook for the future clinical treatment of nerve injuries and advanced tissue engineering.

Conductive, injectable, and self-healing collagen-hyaluronic acid hydrogels loaded with bacterial cellulose and gold nanoparticles for heart tissue engineering

The increasing demand for advanced biomaterials in nerve tissue engineering presents numerous challenges due to the complexity of nerve tissues and the need for materials that can accurately replicate their intricate structure and function. In response, this study introduces a novel injectable hydrogel that is thermosensitive, self-healing, and conductive, offering promising potential for heart and nerve tissue engineering applications. The hydrogel is based on collagen and hyaluronic acid functionalized with 3-aminopropyl-triethoxysilane (APTES)-grafted oxidized bacterial cellulose and gold nanoparticles (~50 nm). Rheological analysis reveals a substantial enhancement in the elastic modulus of the collagen-hyaluronic acid matrix with the incorporation of bacterial cellulose/gold nanoparticles, improving by an order of magnitude at 1 % strain. This improvement comes with a slight decrease in gelation temperature, from 36 °C to 32 °C. Besides thermo-sensitivity, the nanocomposite hydrogel exhibits a remarkable self-sealing response (about 80 % effectiveness) due to reversible physical crosslinking. Electrical spatial resistance measurements on human embryonic stem cell-derived cardiomyocytes-loaded hydrogels yield a value of ~0.1 S/m, which is suitable for electrical stimulation. In vitro extracellular field potential measurements also affirm the hydrogel's potential as an injectable scaffold for heart tissue engineering, i.e., the electrically stimulated human stem cells exhibit 47 beats per minute with a cell discharge (depletion) of 5.47 μv. A rapid gel formation in the physiological temperature (about 2 min) and high H9C2 cytotoxicity (viability of >90 % after 72 h incubation) is attainable. The developed collagen-based nanocomposite hydrogel offers an injectable, thermosensitive, and self-healing biomaterial platform for nerve or myocardium regeneration.

Combining early lower eyelid surgery with neuromuscular retraining for synkinesis prevention after facial palsy: the role of the eye in aberrant facial nerve regeneration.

Facial synkinesis (FS) is a distressing sequela of facial palsy (FP) characterized by involuntary, simultaneous movements of facial muscles occurring during voluntary facial expressions. Treatment of synkinesis is challenging, and preventive methods are needed. This study evaluated the efficacy of physical facial nerve rehabilitation (PFNR) therapy alone vs. PNFR with eyelid surgery to correct lagophthalmos and prevent the onset of synkinesis. Twenty five outpatients were randomized to receive either PFNR alone (neuromuscular retraining and Kabat proprioceptive neuromuscular facilitation) or PNFR and early (90 days after FP onset) eyelid surgery (involving a conservative oculoplastic correction for lagophthalmos with epiphora or ectropion). Comprehensive otolaryngological assessments and Magnetic Resonance Imaging (MRI) were conducted. Synkinesis progression was measured using Another Disease Scale (ADS) at baseline, 3-, 6-, 12-, and 24-months post-treatment. The data were analyzed with ANOVA, τ-test, Chi-Square analyses. Patients undergoing eyelid surgery with PFNR showed faster (p < 0.001) and better recovery of facial movements (p < 0.05) than patients receiving PFNR alone comparing T0 and T12 (p < 0.0001). No synkinesis were observed in the PFNR plus surgery group while 37% of patients in PFNR alone had synkinesis (p = 0.03). At 24 months, none of the patients in the surgery group presented synkinesis. Combining early surgical treatment of paralytic lagophthalmos or epiphora with PFNR accelerated functional recovery and reduced synkinesis in patients with FP compared to facial rehabilitation alone. Further investigations in larger populations with long-term follow-up are needed. https://clinicaltrials.gov/study/NCT06538103, NCT06538103.

Establishment of a Magnetically Controlled Scalable Nerve Injury Model.

Animal models of peripheral nerve injury (PNI) serve as the fundamental basis for the investigations of nerve injury, regeneration, and neuropathic pain. The injury properties of such models, including the intensity and duration, significantly influence the subsequent pathological changes, pain development, and therapeutic efficacy. However, precise control over the intensity and duration of nerve injury remains challenging within existing animal models, thereby impeding accurate and comparative assessments of relevant cases. Here, a new model that provides quantitative and off-body controllable injury properties via a magnetically controlled clamp, is presented. The clamp can be implanted onto the rat sciatic nerve and exert varying degrees of compression under the control of an external magnetic field. It is demonstrated that this model can accurately simulate various degrees of pathology of human patients by adjusting the magnetic control and reveal specific pathological changes resulting from intensity heterogeneity that are challenging to detect previously. The controllability and quantifiability of this model may significantly reduce the uncertainty of central response and inter-experimenter variability, facilitating precise investigations into nerve injury, regeneration, and pain mechanisms.

Enhancing facial nerve regeneration with scaffold-free conduits engineered using dental pulp stem cells and their endogenous, aligned extracellular matrix.

Objective. Engineered nerve conduits must simultaneously enhance axon regeneration and orient axon extension to effectively restore function of severely injured peripheral nerves. The dental pulp contains a population of stem/progenitor cells that endogenously express neurotrophic factors (NTFs), growth factors known to induce axon repair. We have previously generated scaffold-free dental pulp stem/progenitor cell (DPSC) sheets comprising an aligned extracellular matrix (ECM). Through the intrinsic NTF expression of DPSCs and the topography of the aligned ECM, these sheets both induce and guide axon regeneration. Here, the capacity of bioactive conduits generated using these aligned DPSC sheets to restore function in critical-sized nerve injuries in rodents was evaluated.Approach. Scaffold-free nerve conduits were formed by culturing DPSCs on a substrate with aligned microgrooves, inducing the cells to align and deposit an aligned ECM. The sheets were then detached from the substrate and assembled into scaffold-free cylindrical tissues.Main results. In vitroanalyses confirmed that scaffold-free DPSC conduits maintained an aligned ECM and had uniformly distributed NTF expression. Implanting the aligned DPSC conduits across critical-sized defects in the buccal branch of rat facial nerves resulted in the regeneration of a fascicular nerve-like structure and myelinated axon extension across the injury site. Furthermore, compound muscle action potential and stimulated whisker movement measurements revealed that the DPSC conduit treatment promoted similar functional recovery compared to the clinical standard of care, autografts. Significance. This study demonstrates that scaffold-free aligned DPSC conduits supply trophic and guidance cues, key design elements needed to successfully promote and orient axon regeneration. Consequently, these conduits restore function in nerve injuries to similar levels as autograft treatments. These conduits offer a novel bioactive approach to nerve repair capable of improving clinical outcomes and patient quality of life.

A Review and Bibliometric Analysis of Studies on Advances in Peripheral Nerve Regeneration.

Peripheral nerve injuries (PNIs) pose significant clinical challenges due to their complex healing processes and the often incomplete functional recovery. This review and bibliometric analysis aimed to provide a comprehensive overview of advancements in peripheral nerve regeneration research, focusing on trends, influential studies, and emerging areas. By analyzing 2921 publications from the Web of Science Core Collection, key themes such as nerve regeneration, repair, and the critical role of Schwann cells were identified. The study highlights a notable increase in research output since the early 2000s, with China and the United States leading in publication volume and citations. The analysis also underscores the importance of collaborative networks, which are driving innovation in this field. Despite significant progress, the challenge of achieving complete functional recovery from PNIs persists, emphasizing the need for continued research into novel therapeutic strategies. This review synthesizes current knowledge on the mechanisms of nerve regeneration, including the roles of cellular and molecular processes, neurotrophic factors, and emerging therapeutic approaches such as gene therapy and stem cell applications. Additionally, the study revealed the use of nanotechnology, biomaterials, and advanced imaging techniques, which hold promise for improving the outcomes of nerve repair. This bibliometric analysis not only maps the landscape of peripheral nerve regeneration research but also identifies opportunities for future investigation. This study has some limitations, including reliance on the Web of Science Core Collection, which may exclude relevant research from other databases. The analysis is predominantly English-based, potentially overlooking significant non-English studies. Citation trends might be influenced by shifting research priorities and accessibility issues, affecting the visibility of older work. Additionally, geographical disparities and limited collaboration networks may restrict the global applicability and knowledge exchange in this field.

THERAPEUTIC EFFICACY OF MYRTUS COMMUNIS IN SCIATIC NERVE INJURY: AN EXPERIMENTAL RESEARCH IN RATS

OBJECTIVE: Nerve injuries, often resulting from various causes, pose serious health issues that typically require prolonged rehabilitation. Conventional methods used in the treatment of these injuries are often inadequate, necessitating the exploration of new treatment approaches. Research on the effects of plant-derived active compounds on nerve regeneration may offer potential new treatment options. In this context, this study investigating the effects of Myrtus communis on nerve regeneration aims to fill an important gap in the field of nerve injury treatment. MATERIAL AND METHODS: In this study, the efficacy of Myrtus communis was evaluated in an experimental sciatic nerve injury model. Thirty-two female Wistar Albino rats were divided into four groups: Control, Sham, Group I, and Group II. Sciatic nerve injury was induced, and Myrtus communis treatment was administered via gastric lavage. The animals' motor functions, sensory functions, electrophysiological measurements, biochemical parameters, and histopathological evaluations were examined. RESULTS: The results demonstrated that Myrtus communis contributed to rapid improvement in sciatic functional index (SFI) values. Similarly, positive effects were observed in sensory assessment and electrophysiological measurements. Biochemical analyses indicated that Myrtus communis increased antioxidant capacity and reduced oxidative stress. Histopathological examinations revealed less axon degeneration, edema, and vacuolization in the groups treated with Myrtus communis. CONCLUSIONS: This study concludes that Myrtus communis could be used as a potential therapeutic agent in the treatment of sciatic nerve injury. These findings suggest that Myrtus communis may play a supportive role in post-nerve injury recovery. However, it should be noted that further research is needed before these results can be translated into clinical applications.

Research progress of silk-based biomaterials for peripheral nerve regeneration

To describe the research progress of silk-based biomaterials in peripheral nerve repair and provide useful ideals to accelerate the regeneration of large-size peripheral nerve injury. The relative documents about silk-based biomaterials used in peripheral nerve regeneration were reviewed and the different strategies that could accelerate peripheral nerve regeneration through building bioactive microenvironment with silk fibroin were discussed. Many silk fibroin tissue engineered nerve conduits have been developed to provide multiple biomimetic microstructures, and different microstructures have different mechanisms of promoting nerve repair. Biomimetic porous structures favor the nutrient exchange at wound sites and inhibit the invasion of scar tissue. The aligned structures can induce the directional growth of nerve tissue, while the multiple channels promote the axon elongation. When the fillers are introduced to the conduits, better growth, migration, and differentiation of nerve cells can be achieved. Besides biomimetic structures, different nerve growth factors and bioactive drugs can be loaded on silk carriers and released slowly at nerve wounds, providing suitable biochemical cues. Both the biomimetic structures and the loaded bioactive ingredients optimize the niches of peripheral nerves, resulting in quicker and better nerve repair. With silk biomaterials as a platform, fusing multiple ways to achieve the multidimensional regulation of nerve microenvironments is becoming a critical strategy in repairing large-size peripheral nerve injury. Silk-based biomaterials are useful platforms to achieve the design of biomimetic hierarchical microstructures and the co-loading of various bioactive ingredients. Silk fibroin nerve conduits provide suitable microenvironment to accelerate functional recovery of peripheral nerves. Different optimizing strategies are available for silk fibroin biomaterials to favor the nerve regeneration, which would satisfy the needs of various nerve tissue repair. Bioactive silk conduits have promising future in large-size peripheral nerve regeneration.

Effects of the matrix-bounded nanovesicles of high-hydrostatic pressure decellularized tissues on neural regeneration

ABSTRACT Decellularized tissues have been used as implantable materials for tissue regeneration because of their high biofunctionality. We have reported that high hydrostatic pressured (HHP) decellularized tissue developed in our laboratory exhibits good in vivo performance, but the details of the mechanism are still not known. Based on previous reports of bioactive factors called matrix bound nanovesicles (MBVs) within decellularized tissues, this study aims to investigate whether MBVs are also present in decellularized tissues prepared by HHP decellularization, which is different from the previously reported methods. In this study, we tried to extract bioactive factors from HHP decellularized brain and placenta, and evaluated their effects on nerves in vitro and in vivo, where its effects have been previously reported. The results confirmed that those factors can be extracted even if the decellularization method and tissue of origin differ, and that they have effects on a series of processes toward nerve regeneration, such as neurite outgrowth and nerve fiber repair.

Versatile conductive hydrogel orchestrating neuro–immune microenvironment for rapid diabetic wound healing through peripheral nerve regeneration

Diabetic wound (DW), notorious for prolonged healing processes due to the unregulated immune response, neuropathy, and persistent infection, poses a significant challenge to clinical management. Current strategies for treating DW primarily focus on alleviating the inflammatory milieu or promoting angiogenesis, while limited attention has been given to modulating the neuro-immune microenvironment. Thus, we present an electrically conductive hydrogel dressing and identify its neurogenesis influence in a nerve injury animal model initially by encouraging the proliferation and migration of Schwann cells. Further, endowed with the synergizing effect of near-infrared responsive release of curcumin and nature-inspired artificial heterogeneous melanin nanoparticles, it can harmonize the immune microenvironment by restoring the macrophage phenotype and scavenging excessive reactive oxygen species. This in-situ formed hydrogel also exhibits mild photothermal therapy antibacterial efficacy. In the infected DW model, this hydrogel effectively supports nerve regeneration and mitigates the immune microenvironment, thereby expediting the healing progress. The versatile hydrogel exhibits significant therapeutic potential for application in DW healing through fine-tuning the neuro-immune microenvironment.

Rapid Forming, Robust Adhesive Fungal-Sourced Chitosan Hydrogels Loaded with Deferoxamine for Sutureless Short-Gap Peripheral Nerve Repair.

Clinically, conventional sutures for repair of short-distance nerve injuries (< 5mm) may contribute to uncontrolled inflammation and scar formation, thus negatively impacting nerve regeneration. To repair transected peripheral nerves with short distances, a rapid-forming, robust adhesive chitosan hydrogel is prepared by synthesizing maleic and dopamine bi-functionalized fungal-sourced chitosan (DM) and subsequently photopolymerizing DM precursor solution. The hydrogel rapidly polymerized under UV light irradiation (≈2 s) and possessed a strong adhesive strength (273.33 ± 55.07kPa), facilitating a fast bonding of nerve stump. Especially, its tailored degradation profile over 28 days supported both early gap bridging and subsequent nerve regeneration. Furthermore, deferoxamine (DFO), a pro-angiogenic drug, is loaded into the hydrogel to reach sustainable release, accelerating axonal growth synergistically. A 3mm long sciatic nerve defects model in rats is used to investigate the efficacy of DM@DFO hydrogel for repairing peripheral nerve defects. After 60 days, the DM@DFO hydrogel significantly outperformed conventional sutures and fibrin glue, improving motor and sensory recovery by reducing inflammation, inhibiting scar formation, and accelerating vascular regeneration within 14 days post-repair. This work highlights the DM@DFO hydrogel as a promising tissue adhesive for effective short-distance peripheral nerve repair.

Nuclear Magnetic Resonance Treatment Induces ßNGF Release from Schwann Cells and Enhances the Neurite Growth of Dorsal Root Ganglion Neurons In Vitro.

Peripheral nerve regeneration depends on close interaction between neurons and Schwann cells (SCs). After nerve injury, SCs produce growth factors and cytokines that are crucial for axon re-growth. Previous studies revealed the supernatant of SCs exposed to nuclear magnetic resonance therapy (NMRT) treatment to increase survival and neurite formation of rat dorsal root ganglion (DRG) neurons in vitro. The aim of this study was to identify factors involved in transferring the observed NMRT-induced effects to SCs and consequently to DRG neurons. Conditioned media of NMRT-treated (CM NMRT) and untreated SCs (CM CTRL) were tested by beta-nerve growth factor (ßNGF) ELISA and multiplex cytokine panels to profile secreted factors. The expression of nociceptive transient receptor potential vanilloid 1 (TRPV1) channels was assessed and the intracellular calcium response in DRG neurons to high-potassium solution, capsaicin or adenosine triphosphate was measured mimicking noxious stimuli. NMRT induced the secretion of ßNGF and pro-regenerative-signaling factors. Blocking antibody experiments confirmed ßNGF as the main factor responsible for neurotrophic/neuritogenic effects of CM NMRT. The TRPV1 expression or sensitivity to specific stimuli was not altered, whereas the viability of cultured DRG neurons was increased. Positive effects of CM NMRT supernatant on DRG neurons are primarily mediated by increased ßNGF levels.

Adipose-derived stem cell transplantation enhances spinal cord regeneration by upregulating PGRN expression.

This study aims to investigate the effect of adipose-derived stem cells (ADSCs) transplantation on progranulin (PGRN) expression and functional recovery in rats with spinal cord injury (SCI). ADSCs were isolated from the inguinal adipose tissue of rats. A SCI model was created, and ADSCs were injected into the injured area. Various techniques were used to assess the effects of ADSCs transplantation, including hematoxylin-eosin staining, Masson staining, immunofluorescence staining, electron microscopy, MRI, and motor function assessment. The potential mechanisms of ADSC transplantation were investigated using gene expression analysis and protein analysis. Finally, the safety of this therapy was evaluated through hematoxylin-eosin staining and indicators of liver and kidney damage in serum. PGRN expression increased in the injured spinal cord, and ADSCs transplantation further enhanced PGRN levels. The group that received ADSCs transplantation showed reduced inflammation, decreased scar formation, increased nerve regeneration, and faster recovery of bladder function. Importantly, motor function significantly improved in the ADSC transplantation group. ADSCs transplantation enhances functional regeneration in SCI by upregulating PGRN expression, reducing inflammation and scar formation, and promoting nerve regeneration and myelin repair. These findings suggest that ADSC transplantation is a potential therapy for SCI.

Tensile Strength of Nerve Bridging Models Using Collagen Nerve Conduits.

In the treatment of peripheral nerve injuries with nerve defects, second-generation collagen-based conduits, such as Renerve® (Nipro, Osaka, Japan), have shown the potential for promoting nerve regeneration. However, there is concern related to the weak material properties. No previous studies have addressed the strength of the bridging model using collagen conduits. This study aimed to investigate the tensile strength and failure patterns in nerve defect models bridged with Renerve® conduits through biomechanical research. Using fresh chicken sciatic nerves, we examined the maximum failure load of four groups: bridging models using Renerve® with one suture (group A), with two sutures (group B), with three sutures (group C), and end-to-end neurorrhaphy models with two sutures (group N). Each group had eight specimens. We also evaluated failure patterns of the specimens. Group N showed a significantly higher maximum failure load (0.96 ± 0.13 N) compared to groups A (0.23 ± 0.06 N, p < 0.0001), B (0.29 ± 0.05 N, p < 0.0001), and C (0.40 ± 0.10 N, p < 0.0001). Regarding failure patterns, all specimens in group A showed nerve-end dislocation from the conduit. Two specimens in group B and three specimens in group C failed due to circumferential cracks in the conduit. Six specimens in group B and five specimens in group C exhibited cutting out of sutures from the conduit. This study suggests that the number of sutures in synthetic collagen nerve conduits has little effect on the maximum failure load. To take advantage of its biomaterial benefits, a period of postoperative range of motion restriction may be required.

Inhibition of CRMP2 Phosphorylation Suppresses Microglia Activation in the Retina and Optic Nerve and Promotes Optic Nerve Regeneration After Optic Nerve Injury

As the primary connection between the eye and brain, the optic nerve plays a pivotal role in visual information transmission. Injuries to the optic nerve can occur for various reasons, including trauma, glaucoma, and neurodegenerative diseases. Retinal ganglion cells (RGCs), a type of neurons that extend axons through the optic nerve, can rapidly respond to injury and initiate cell death. Additionally, following optic nerve injury microglia, which serve as markers of neuroinflammation, transition from a resting state to an activated state. The phosphorylation of collapsin response mediator protein2 (CRMP2) in the semaphorin 3A (Sema3A) signalling pathway affects several processes, including axon guidance and neuron regeneration. In this study, we used an optic nerve crush (ONC) mouse model to investigate the effects of suppressing CRMP2 phosphorylation on microglia activation. We found that CRMP2 phosphorylation inhibitor suppressed RGCs loss and promoted neuronal regeneration following ONC. In addition, CRMP2 S522A mutant (CRMP2 KI) mice exhibited decreased microglial activation in both the retina and optic nerve following ONC. These results suggest that inhibiting the phosphorylation of CRMP2 can alleviate the loss of RGCs and microglial activation after optic nerve injury, providing insight into the development of treatments for optical neuropathies and neurodegenerative diseases.

Hepatocyte growth factor facilitates the repair of spinal cord injuries by driving the chemotactic migration of mesenchymal stem cells through the β-catenin/TCF4/Nedd9 signaling pathway.

Transplanted mesenchymal stem cells (MSCs) can significantly aid in repairing spinal cord injuries (SCIs) by migrating to and settling at the injury site. However, this process is typically inefficient, as only a small fraction of MSCs successfully reach the target lesion area. During SCI, the increased expression and secretion of hepatocyte growth factor (HGF) act as a chemoattractant that guides MSC migration. Nonetheless, the precise mechanisms by which HGF influences MSC migration are not fully understood. This study focused on unraveling the molecular pathways that drive MSC migration toward the SCI site in response to HGF. It was found that HGF can activate β-catenin signaling in MSCs by either phosphorylating LRP6, suppressing GSK3β phosphorylation through the AKT and ERK1/2 pathways, or enhancing the expression and nuclear translocation of TCF4. This activation leads to elevated Nedd9 expression, which promotes focal adhesion formation and F-actin polymerization, facilitating chemotactic migration. Transplanting MSCs during peak HGF expression in injured tissues substantially improves nerve regeneration, reduces scarring, and enhances hind limb mobility. Additionally, prolonging HGF release can further boost MSC migration and engraftment, thereby amplifying regenerative outcomes. However, inhibiting HGF/Met or interfering with β-catenin or Nedd9 signaling significantly impairs MSC engraftment, obstructing tissue repair and functional recovery. Together, these findings provide a theoretical basis and practical strategy for MSC transplantation therapy in SCI, highlighting the specific molecular mechanisms by which HGF regulates β-catenin signaling in MSCs, ultimately triggering their chemotactic migration.

Three-dimensional chromatin mapping of sensory neurons reveals that promoter–enhancer looping is required for axonal regeneration

The in vivo three-dimensional genomic architecture of adult mature neurons at homeostasis and after medically relevant perturbations such as axonal injury remains elusive. Here, we address this knowledge gap by mapping the three-dimensional chromatin architecture and gene expression program at homeostasis and after sciatic nerve injury in wild-type and cohesin-deficient mouse sensory dorsal root ganglia neurons via combinatorial Hi-C, promoter-capture Hi-C, CUT&Tag for H3K27ac and RNA-seq. We find that genes involved in axonal regeneration form long-range, complex chromatin loops, and that cohesin is required for the full induction of the regenerative transcriptional program. Importantly, loss of cohesin results in disruption of chromatin architecture and severely impaired nerve regeneration. Complex enhancer-promoter loops are also enriched in the human fetal cortical plate, where the axonal growth potential is highest, and are lost in mature adult neurons. Together, these data provide an original three-dimensional chromatin map of adult sensory neurons in vivo and demonstrate a role for cohesin-dependent long-range promoter interactions in nerve regeneration.

Analysis of artificial intelligence medical treatment for closed muscle skin nerve injury caused by aerobics training

In aerobics training, closed myocutaneous nerve damage needs to be paid attention to, especially high-intensity training may cause minor damage to muscles and nerves. With the help of AI medical technology and the understanding of molecular and cellular biomechanics, we can more accurately explore the mechanism of injury, such as the effects of nerve tensile stress and microenvironment changes on nerve regeneration. This helps to develop scientific rehabilitation methods, such as AI-assisted personalized training, neural regeneration technology, and real-time monitoring of training intensity to speed up athletes’ rehabilitation and reduce the risk of future injuries. Purpose: Aerobics training is very strict and requires high physical fitness of dancers. During long-term training, dancers can easily cause closed musculocutaneous nerve injury. Traditional medicine is difficult to guarantee the treatment effect of patients with musculocutaneous nerve injury. The use of artificial intelligence medicine for closed musculocutaneous nerve injury treatment can improve the treatment effect of aerobics training induced closed musculocutaneous nerve injury. Method: This article utilized artificial intelligence medicine for the treatment of musculocutaneous nerve injury, and used artificial intelligence technology to analyze patient imaging and other data to assist doctors in accurate diagnosis. Utilize intelligent algorithms to predict medication plans, reduce medication errors, and intelligently adjust the course of treatment based on the patient’s condition. In artificial intelligence healthcare, high-quality online medical services can be created through intelligent technology, providing convenient medical consultation for patients. Result: This article selected 200 patients with musculocutaneous nerve injury caused by aerobics training for grouping experiments. The average diagnostic accuracy of traditional medicine and artificial intelligence medicine were 84.2% and 95.6%, respectively. Conclusion: Artificial intelligence medicine can achieve medical informatization and intelligently analyze patients’ medical information, which helps to improve the accuracy of medical diagnosis for aerobics training injuries.

Glycerol-blended chitosan membranes with directional micro-grooves and reduced stiffness improve Schwann cell wound healing

Regenerative medicine is continuously looking for new natural, biocompatible and possibly biodegradable materials, but also mechanically compliant. Chitosan is emerging as a promising FDA-approved biopolymer for tissue engineering, however, its exploitation in regenerative devices is limited by its brittleness and can be further improved, for example by blending it with other materials or by tuning its superficial microstructure. Here, we developed membranes made of chitosan (Chi) and glycerol, by solvent casting, and micro-patterned them with directional geometries having different levels of axial symmetry. These membranes were characterized by light microscopies, atomic force microscopy (AFM), by thermal, mechanical and degradation assays, and also testedin vitroas scaffolds with Schwann cells (SCs). The glycerol-blended Chi membranes are optimized in terms of mechanical properties, and present a physiological-grade Young's modulus (≈0.7 MPa). The directional topographies are effective in directing cell polarization and migration and in particular are highly performant substrates for collective cell migration. Here, we demonstrate that a combination of a soft compliant biomaterial and a topographical micropatterning can improve the integration of these scaffolds with SCs, a fundamental step in the peripheral nerve regeneration process.

Highly aligned electroactive ultrafine fibers promote the differentiation of mesenchymal stem cells into Schwann-like cells for nerve regeneration

This study investigates the efficacy of a novel tissue-engineered scaffold for nerve repair and functional reconstruction following injury. Utilizing stable jet electrospinning, we fabricated aligned ultrafine fibers from dopamine and poly(L-lactic acid) (PLLA), further developing a biomimetic, oriented, and electroactive scaffold comprising poly(pyrrole) (PPy), polydopamine (PDA), and PLLA through dual in situ polymerizations. The scaffold demonstrated enhanced cell adhesion and reactive oxygen species (ROS) scavenging capabilities and promoted the differentiation of mesenchymal stem cells (MSCs) into Schwann-like cells, essential for nerve regeneration. In vivo assessments revealed significant peripheral nerve regeneration in 10 mm sciatic nerve defects in rats, with observations made 12 weeks post-transplantation. This included facilitated myelination and increased muscle density on the injured side, leading to improved motor function recovery. Our results suggest that the aligned PPy/PDA/PLLA fibrous scaffold offers a promising approach for promoting the differentiation of MSCs into Schwann-like cells conducive to nerve regeneration and represents a significant advancement in nerve repair technologies. This study provides a foundational basis for future research into tissue-engineered solutions for nerve damage, potentially impacting clinical strategies for nerve reconstruction.