Schwann cells and macrophages are the main immune cells involved in peripheral nerve injury. After injury, Schwann cells produce an inflammatory response and secrete various chemokines, inflammatory factors, and some other cytokines to promote the recruitment and M2 polarization of blood-derived macrophages, enhancing their phagocytotic ability, and thus play an important role in promoting nerve regeneration. Macrophages have also been found to promote vascular regeneration after injury, promote the migration and proliferation of Schwann cells along blood vessels, and facilitate myelination and axon regeneration. Therefore, there is a close interaction between Schwann cells and macrophages during peripheral nerve regeneration, but this has not been systematically summarized. In this review, the mechanisms of action of Schwann cells and macrophages in each other's migration and phenotypic transformation are reviewed from the perspective of each other, to provide directions for research on accelerating nerve injury repair.
Schwann Cells/metabolism* ; Peripheral Nerve Injuries/physiopathology* ; Animals ; Macrophages/immunology* ; Nerve Regeneration/physiology* ; Humans ; Cell Movement/physiology*

OBJECTIVE: Treating peripheral nerve injury (PNI) presents a clinical challenge due to limited axon regeneration. Strychni Semen, a traditional Chinese medicine, is clinically used for numbness and hemiplegia. However, its role in promoting functional recovery after PNI and the related mechanisms have not yet been systematically studied. METHODS: A mouse model of sciatic nerve crush (SNC) injury was established and the mice received drug treatment via intragastric gavage, followed by behavioral assessments (adhesive removal test, hot-plate test and Von Frey test). Transcriptomic analyses were performed to examine gene expression in the dorsal root ganglia (DRGs) from the third to the sixth lumbar vertebrae, so as to identify the significantly differentially expressed genes. Immunofluorescence staining was used to assess the expression levels of superior cervical ganglia neural-specific 10 protein (SCG10). The ultra-trace protein detection technique was used to evaluate changes in gene expression levels. RESULTS: Strychni Semen and its active compounds (brucine and strychnine) improved functional recovery in mice following SNC injury. Transcriptomic data indicated that Strychni Semen and its active compounds initiated transcriptional reprogramming that impacted cellular morphology and extracellular matrix remodeling in DRGs after SNC, suggesting potential roles in promoting axon regeneration. Imaging data further confirmed that Strychni Semen and its active compounds facilitated axon regrowth in SNC-injured mice. By integrating protein-protein interaction predictions, ultra-trace protein detection, and molecular docking analysis, we identified myeloperoxidase as a potentially critical factor in the axon regenerative effects conferred by Strychni Semen and its active compounds. CONCLUSION Strychni Semen and its active compounds enhance sensory function by promoting axonal regeneration after PNI. These findings establish a foundation for the future applications of Strychni Semen and highlight novel therapeutic strategies and drug targets for axon regeneration. Please cite this article as: Zhang Y, Zhao XY, Liu MT, Zhou ZC, Cheng HB, Jiang XH, Zheng YR, Chen Z. Strychni Semen and its active compounds promote axon regeneration following peripheral nerve injury by suppressing myeloperoxidase in the dorsal root ganglia. J Integr Med. 2025; 23(2): 169-181.
Animals ; Nerve Regeneration/drug effects* ; Mice ; Peripheral Nerve Injuries/physiopathology* ; Male ; Ganglia, Spinal/enzymology* ; Axons/physiology* ; Peroxidase/antagonists & inhibitors* ; Mice, Inbred C57BL ; Drugs, Chinese Herbal/pharmacology* ; Disease Models, Animal ; Strychnine/pharmacology*

PURPOSE: This study was performed to examine the treatment of erectile dysfunction by use of superparamagnetic iron oxide nanoparticles-labeled human mesenchymal stem cells (SPION-MSCs) transplanted into the cavernous nerve injured cavernosa of rats as monitored by molecular magnetic resonance imaging (MRI). MATERIALS AND METHODS: Eight-week-old male Sprague-Dawley rats were divided into three groups of 10 rats each: group 1, sham operation; group 2, cavernous nerve injury; group 3, SPION-MSC treatment after cavernous nerve injury. Immediately after the cavernous nerve injury in group 3, SPION-MSCs were injected into the cavernous nerve injured cavernosa. Serial T2-weighted MRI was done immediately after injection and at 2 and 4 weeks. Erectile response was assessed by cavernous nerve stimulation at 2 and 4 weeks. RESULTS: Prussian blue staining of SPION-MSCs revealed abundant uptake of SPION in the cytoplasm. After injection of 1x10(6) SPION-MSCs into the cavernosa of rats, T2-weighted MRI showed a clear hypointense signal induced by the injection. The presence of SPION in the corpora cavernosa was confirmed with Prussian blue staining. At 2 and 4 weeks, rats with cavernous nerve injury had significantly lower erectile function than did rats without cavernous nerve injury (p<0.05). The group transplanted with SPION-MSCs showed higher erectile function than did the group without SPION-MSCs (p<0.05). The presence of SPION-MSCs for up to 4 weeks was confirmed by MRI imaging and Prussian blue staining in the corpus cavernosa. CONCLUSIONS: Transplanted SPION-MSCs existed for up to 4 weeks in the cavernous nerve injured cavernosa of rats. Erectile dysfunction recovered and could be monitored by MRI.
Animals ; Contrast Media/pharmacology ; Dextrans/*pharmacology ; Disease Models, Animal ; Drug Delivery Systems/methods ; *Erectile Dysfunction/diagnosis/etiology/therapy ; Magnetic Resonance Imaging/methods ; *Magnetite Nanoparticles ; Male ; Mesenchymal Stem Cell Transplantation/*methods ; Monitoring, Physiologic/methods ; Penis/*innervation ; *Peripheral Nerve Injuries/complications/diagnosis/physiopathology/therapy ; Rats ; Suspensions ; Treatment Outcome

OBJECTIVE: This study was conducted to ascertain the correlation between preserved pelvic nerve networks and bladder function after laparoscopic nerve-sparing radical hysterectomy. METHODS: Between 2009 and 2011, 53 patients underwent total laparoscopic radical hysterectomies. They were categorized into groups A, B, and C based on the status of preserved pelvic nerve networks: complete preservation of the pelvic nerve plexus (group A, 27 cases); partial preservation (group B, 13 cases); and complete sacrifice (group C, 13 cases). To evaluate bladder function, urodynamic studies were conducted preoperatively and postoperatively at 1, 3, 6, and 12 months after surgery. RESULTS: No significant difference in sensory function was found between groups A and B. However, the sensory function of group C was significantly lower than that of the other groups. Group A had significantly better motor function than groups B and C. No significant difference in motor function was found between groups B and C. Results showed that the sensory nerve is distributed predominantly at the dorsal half of the pelvic nerve networks, but the motor nerve is predominantly distributed at the ventral half. CONCLUSION: Various types of total laparoscopic nerve-sparing radical hysterectomies can be tailored to patients with cervical carcinomas.
Adult ; Aged ; Female ; Humans ; Hypogastric Plexus/injuries ; Hysterectomy/adverse effects/*methods ; Laparoscopy/adverse effects/*methods ; Middle Aged ; Neoplasm Staging ; Pelvis/innervation ; Peripheral Nerve Injuries/etiology/*prevention & control ; Postoperative Period ; Urinary Bladder/*innervation/physiopathology ; Urodynamics ; Uterine Cervical Neoplasms/pathology/*surgery

Neural stem cells (NSCs) and Schwann cells (SCs) both play an important role in the recovery and regeneration of peripheral nerve injury, which makes them become the focus in the field of nerve injury research. SCs provide a suitable microenvironment for the recovery and regeneration of injured peripheral nerve through secreting various cytokines and other related factors, and they can significantly promote the differentiation of NSCs into neurons. Recently with the development of microsurgical technique, using nerve conduits along with NSCs and SCs to bridge nerve stumps so as to repair peripheral nerve injury has now attracted increasing research interest. In this article, we focus on the effects and mechanisms of NSCs and SCs on peripheral nerve injury and regeneration process, and describe the future trend and potential clinical application of the technology combining both two cells and nerve conduits to repair peripheral nerve injury.
Animals ; Cells, Cultured ; Humans ; Nerve Regeneration ; Neural Stem Cells ; Peripheral Nerve Injuries ; physiopathology ; surgery ; Schwann Cells

Animals ; Macaca mulatta ; Nerve Regeneration ; Peripheral Nerve Injuries ; physiopathology ; Peripheral Nerves ; physiology ; Rats

OBJECTIVE: To explore the application value of needle electromyography (EMG) and nerve conduction study (NCS) in the forensic appraisal; to provide scientific basis for establishing normative and unified assessment methods of the peripheral nerve study in forensic medicine. METHODS: One hundred and sixty-four samples with injured peripheral nerve (injury group) and 138 samples with normal peripheral nerve (control group) were collected and tested with methods of EMG and NCS respectively. The relevance rate of two methods were compared and statistical analysis was performed. RESULTS: In the injury group, there was no statistical difference on the relevance rate between the application of EMG and that of NCS (P > 0.05). In the control group, there was no statistical difference on the negative rate between the two methods (P > 0.05). The false negative rate of the injury group and the false positive rate of the control group were both 0% when using the two methods together. CONCLUSION When the injured peripheral nerve in forensic appraisal is in doubt, application of both EMG and NCS could disclose truth from falsehood. The accuracy and credibility of identification results could be enhanced.
Action Potentials ; Adolescent ; Adult ; Case-Control Studies ; Electromyography/methods* ; Female ; Forensic Medicine/methods* ; Humans ; Lower Extremity/injuries* ; Male ; Middle Aged ; Muscle, Skeletal/physiopathology* ; Needles ; Neural Conduction/physiology* ; Peripheral Nerve Injuries/physiopathology* ; Trauma Severity Indices ; Upper Extremity/injuries* ; Young Adult

The present study is to investigate whether the extracellular signal-regulated kinase (ERK) and cAMP response element binding protein (CREB) signaling pathway contributes to the initiation of chronic constriction injury (CCI)-induced neuropathic pain in rats. Mechanical allodynia was assessed by measuring the hindpaw withdrawal threshold in response to a calibrated series of von Frey hairs. Thermal hyperalgesia was assessed by measuring the latency of paw withdrawal in response to a radiant heat source. The expressions of phosphor-ERK (pERK) and phosphor-CREB (pCREB) were examined using Western blot analysis and immunohistochemistry. An early robust increase in the expression of pERK on the spinal cords ipsilateral to injury was observed on day 1 after CCI, when the CCI-induced behavioral hypersensitivity had not developed yet. Moreover, the upregulation of pERK expression in ipsilateral spinal cord was associated with the increase in pCREB expression in bilateral spinal cord. Intrathecal administration of mitogen-activated protein kinase kinase (MEK) inhibitor U0126 before CCI can efficiently block and delay the CCI-induced mechanical allodynia and thermal hyperalgesia. These data suggest that activation of ERK and CREB in the spinal cord contributes to the initiation of peripheral nerve injury-induced pain hypersensitivity, and an early intervention strategy should be proposed.
Animals ; Butadienes ; pharmacology ; Cyclic AMP Response Element-Binding Protein ; metabolism ; Enzyme Inhibitors ; pharmacology ; Extracellular Signal-Regulated MAP Kinases ; metabolism ; Hyperalgesia ; etiology ; physiopathology ; prevention & control ; Male ; Nitriles ; pharmacology ; Pain ; etiology ; physiopathology ; prevention & control ; Peripheral Nerve Injuries ; complications ; metabolism ; physiopathology ; Rats ; Rats, Sprague-Dawley ; Sciatic Neuropathy ; metabolism ; physiopathology ; Spinal Cord ; metabolism

BACKGROUNDPeripheral nerve injury causes a high rate of disability and a huge economic burden, and is currently one of the serious health problems in the world. The use of nerve grafts plays a vital role in repairing nerve defects. Acellular nerve grafts have been widely used in many experimental models as a peripheral nerve substitute. The purpose of this study was to test the biomechanical properties of acellular nerve grafts.

METHODSThirty-four fresh sciatic nerves were obtained from 17 adult male Wistar rats (age of 3 months) and randomly assigned to 3 groups: normal control group, nerve segments underwent no treatment and were put in phosphate buffered saline (pH 7.4) and stored at 4°C until further use; physical method group, nerve segments were frozen at -196°C and then thawed at 37°C; and chemical method group, nerve segments were chemically extracted with the detergents Triton X-200, sulfobetaine-10 (SB-10) and sulfobetaine-16 (SB-16). After the acellularization process was completed, the structural changes of in the sciatic nerves in each group were observed by hematoxylin-eosin staining and field emission scanning electron microscopy, then biomechanical properties were tested using a mechanical apparatus (Endura TEC ELF 3200, Bose, Boston, USA).

RESULTSHematoxylin-eosin staining and field emission scanning electron microscopy demonstrated that the effects of acellularization, demyelination, and integrity of nerve fiber tube of the chemical method were better than that of the physical method. Biomechanical testing showed that peripheral nerve grafts treated with the chemical method resulted in some decreased biomechanical properties (ultimate load, ultimate stress, ultimate strain, and mechanical work to fracture) compared with normal control nerves, but the differences were not statistically significant (P > 0.05).

CONCLUSIONNerve treated with the chemical method may be more appropriate for use in implantation than nerve treated with the physical method.

Animals ; Biomechanical Phenomena ; Male ; Microscopy, Electron, Scanning ; Peripheral Nerve Injuries ; therapy ; Peripheral Nerves ; physiology ; ultrastructure ; Rats ; Rats, Wistar ; Sciatic Nerve ; physiopathology ; ultrastructure ; Tissue Engineering

OBJECTIVE: To study the characteristics of forensic identification cases involved with peripheral nerve injury, and to discuss how to apply the clinical information, forensic examination and neurophysiological testing. METHODS: One hundred and fifty-eight cases which were diagnosed peripheral nerve injury in clinic, were collected. Then the individual characteristics, injuries, identification results, exaggeration or camouflage were analysed. RESULTS: The male, the unemployed, and the young and middle-aged were common in our cases. The main reasons of "peripheral nerve injury" were traffic accidents and sharp injuries. Most wounded parts were in limbs. Also the exaggeration and camouflage accounted for a considerable proportion in our cases. CONCLUSION The forensic identification of "peripheral nerve injury" cases should be evaluated with clinical information, forensic examination and electrophysiological testing comprehensively.
Accidents, Traffic ; Adolescent ; Adult ; Age Distribution ; Disability Evaluation ; Electromyography ; Electrophysiology ; Female ; Forensic Medicine ; Humans ; Male ; Middle Aged ; Neural Conduction/physiology* ; Peripheral Nerve Injuries ; Peripheral Nerves/physiopathology* ; Peripheral Nervous System Diseases/physiopathology* ; Retrospective Studies ; Trauma Severity Indices ; Wounds, Nonpenetrating/physiopathology* ; Young Adult