White matter injury (WMI) is a major form of brain injury in preterm infants. Its characteristic pathological features primarily involve impaired development of oligodendrocyte precursor cells and structural damage to axons, which can lead to the neurological sequelae such as motor, behavioral, and cognitive dysfunctions. Chondroitin sulfate proteoglycans (CSPGs), as the important components of extracellular matrix, can participate in neuroinflammatory response mediated by microglial cells and dynamically balance glial scar reconstruction and axon growth by regulating specific receptors and signaling pathways. This article reviews the relationship between CSPGs and WMI, as well as the mechanisms by which CSPGs inhibit axon growth, focusing on the role of multi-target regulation of CSPGs in promoting axon plasticity and functional brain recovery, thereby providing a theoretical basis for improving the prognosis of preterm infants with WMI.
Humans ; Chondroitin Sulfate Proteoglycans/physiology* ; White Matter/pathology* ; Axons/physiology* ; Infant, Premature ; Infant, Newborn ; Animals

Demyelination and remyelination play key roles in spinal cord injury (SCI), affecting the recovery of motor and sensory functions. Research in rodent models is extensive, but the study of these processes in non-human primates is limited. Therefore, our goal was to thoroughly study the histological features of demyelination and remyelination after contusion injury of the cervical spinal cord in Macaca fascicularis. In a previous study, we created an SCI model in M. fascicularis by controlling the contusion displacement. We used Eriochrome Cyanine staining, immunohistochemical analysis, and toluidine blue staining to evaluate demyelination and remyelination. The results showed demyelination ipsilateral to the injury epicenter both rostrally and caudally, the former mainly impacting sensory pathways, while the latter primarily affected motor pathways. Toluidine blue staining showed myelin loss and axonal distension at the injury site. Schwann cell-derived myelin sheaths were only found at the center, while thinner myelin sheaths from oligodendrocytes were seen at the center and surrounding areas. Our study showed that long-lasting demyelination occurs in the spinal cord of M. fascicularis after SCI, with oligodendrocytes and Schwann cells playing a significant role in myelin sheath formation at the injury site.
Animals ; Spinal Cord Injuries/physiopathology* ; Demyelinating Diseases/etiology* ; Remyelination/physiology* ; Macaca fascicularis ; Disease Models, Animal ; Myelin Sheath/pathology* ; Oligodendroglia/pathology* ; Schwann Cells/pathology* ; Female ; Spinal Cord/pathology* ; Axons/pathology*

Amyotrophic Lateral Sclerosis (ALS) is a complex neurodegenerative disorder characterized by progressive axonopathy, jointly leading to the dying back of the motor neuron, disrupting both nerve signaling and motor control. In this review, we highlight the roles of axonopathy in ALS progression, driven by the interplay of multiple factors including defective trafficking machinery, protein aggregation, and mitochondrial dysfunction. Dysfunctional intracellular transport, caused by disruptions in microtubules, molecular motors, and adaptors, has been identified as a key contributor to disease progression. Aberrant protein aggregation involving TDP-43, FUS, SOD1, and dipeptide repeat proteins further amplifies neuronal toxicity. Mitochondrial defects lead to ATP depletion, oxidative stress, and Ca²⁺ imbalance, which are regarded as key factors underlying the loss of neuromuscular junctions and axonopathy. Mitigating these defects through interventions including neurotrophic treatments offers therapeutic potential. Collaborative research efforts aim to unravel ALS complexities, opening avenues for holistic interventions that target diverse pathological mechanisms.
Humans ; Amyotrophic Lateral Sclerosis/therapy* ; Animals ; Axons/metabolism* ; Mitochondria/metabolism* ; Motor Neurons/pathology*

Spinal cord injury (SCI) disrupts the structural and functional connectivity between the higher center and the spinal cord, resulting in severe motor, sensory, and autonomic dysfunction with a variety of complications. The pathophysiology of SCI is complicated and multifaceted, and thus individual treatments acting on a specific aspect or process are inadequate to elicit neuronal regeneration and functional recovery after SCI. Combinatory strategies targeting multiple aspects of SCI pathology have achieved greater beneficial effects than individual therapy alone. Although many problems and challenges remain, the encouraging outcomes that have been achieved in preclinical models offer a promising foothold for the development of novel clinical strategies to treat SCI. In this review, we characterize the mechanisms underlying axon regeneration of adult neurons and summarize recent advances in facilitating functional recovery following SCI at both the acute and chronic stages. In addition, we analyze the current status, remaining problems, and realistic challenges towards clinical translation. Finally, we consider the future of SCI treatment and provide insights into how to narrow the translational gap that currently exists between preclinical studies and clinical practice. Going forward, clinical trials should emphasize multidisciplinary conversation and cooperation to identify optimal combinatorial approaches to maximize therapeutic benefit in humans with SCI.
Humans ; Axons/pathology* ; Nerve Regeneration/physiology* ; Spinal Cord Injuries/therapy* ; Neurons/pathology* ; Recovery of Function

When ischemia or hemorrhagic stroke occurs, astrocytes are activated by a variety of endogenous regulatory factors to become reactive astrocytes. Subsequently, reactive astrocytes proliferate, differentiate, and migrate around the lesion to form glial scar with the participation of microglia, neuron-glial antigen 2(NG2) glial cells, and extracellular matrix. The role of glial scars at different stages of stroke injury is different. At the middle and late stages of the injury, the secreted chondroitin sulfate proteoglycan and chondroitin sulfate are the main blockers of axon regeneration and nerve function recovery. Targeted regulation of glial scars is an important pathway for neurological rehabilitation after stroke. Chinese medicine has been verified to be effective in stroke rehabilitation in clinical practice, possibly because it has the functions of promoting blood resupply, anti-inflammation, anti-oxidative stress, inhibiting cell proliferation and differentiation, and benign intervention in glial scars. This study reviewed the pathological process and signaling mechanisms of glial scarring after stroke, as well as the intervention of traditional Chinese medicine upon glial scar, aiming to provide theoretical reference and research evidence for developing Chinese medicine against stroke in view of targeting glial scarring.
Astrocytes ; Axons/pathology* ; Cicatrix/pathology* ; Gliosis/pathology* ; Humans ; Medicine, Chinese Traditional ; Nerve Regeneration ; Stroke/drug therapy*

Spinal cord injury (SCI), which is much in the public eye, is still a refractory disease compromising the well-being of both patients and society. In spite of there being many methods dealing with the lesion, there is still a deficiency in comprehensive strategies covering all facets of this damage. Further, we should also mention the structure called the corticospinal tract (CST) which plays a crucial role in the motor responses of organisms, and it will be the focal point of our attention. In this review, we discuss a variety of strategies targeting different dimensions following SCI and some treatments that are especially efficacious to the CST are emphasized. Over recent decades, researchers have developed many effective tactics involving five approaches: (1) tackle more extensive regions; (2) provide a regenerative microenvironment; (3) provide a glial microenvironment; (4) transplantation; and (5) other auxiliary methods, for instance, rehabilitation training and electrical stimulation. We review the basic knowledge on this disease and correlative treatments. In addition, some well-formulated perspectives and hypotheses have been delineated. We emphasize that such a multifaceted problem needs combinatorial approaches, and we analyze some discrepancies in past studies. Finally, for the future, we present numerous brand-new latent tactics which have great promise for curbing SCI.
Animals ; Astrocytes/cytology* ; Axons/physiology* ; Cell Transplantation ; Disease Models, Animal ; Electric Stimulation ; Humans ; Microglia/cytology* ; Motor Neurons/cytology* ; Nerve Regeneration ; Neuroglia/cytology* ; Neuronal Plasticity ; Neurons/cytology* ; Oligodendroglia/cytology* ; Pyramidal Tracts/pathology* ; Recovery of Function ; Regenerative Medicine/methods* ; Spinal Cord Injuries/therapy*

BACKGROUND: Stroke involving the cerebral white matter (WM) has increased in prevalence, but most experimental studies have focused on ischemic injury of the gray matter. This study was performed to investigate the WM in a unique rat model of photothrombotic infarct targeting the posterior limb of internal capsule (PLIC), focusing on the identification of the most vulnerable structure in WM by ischemic injury, subsequent glial reaction to the injury, and the fundamental histopathologic feature causing different neurologic outcomes. METHODS: Light microscopy with immunohistochemical stains and electron microscopic examinations of the lesion were performed between 3 hours and 21 days post-ischemic injury. RESULTS: Initial pathological change develops in myelinated axon, concomitantly with reactive change of astrocytes. The first pathology to present is nodular loosening to separate the myelin sheath with axonal wrinkling. Subsequent pathologies include rupture of the myelin sheath with extrusion of axonal organelles, progressive necrosis, oligodendrocyte degeneration and death, and reactive gliosis. Increase of glial fibrillary acidic protein (GFAP) immunoreactivity is an early event in the ischemic lesion. WM pathologies result in motor dysfunction. Motor function recovery after the infarct was correlated to the extent of PLIC injury proper rather than the infarct volume. CONCLUSIONS: Pathologic changes indicate that the cerebral WM, independent of cortical neurons, is highly vulnerable to the effects of focal ischemia, among which myelin sheath is first damaged. Early increase of GFAP immunoreactivity indicates that astrocyte response initially begins with myelinated axonal injury, and supports the biologic role related to WM injury or plasticity. The reaction of astrocytes in the experimental model might be important for the study of pathogenesis and treatment of the WM stroke.
Astrocytes ; Axons ; Coloring Agents ; Extremities ; Glial Fibrillary Acidic Protein ; Gliosis ; Gray Matter ; Internal Capsule* ; Ischemia ; Microscopy ; Models, Animal ; Models, Theoretical ; Myelin Sheath ; Necrosis ; Neurons ; Oligodendroglia ; Organelles ; Pathology ; Plastics ; Prevalence ; Recovery of Function ; Rupture ; Stroke ; White Matter

Evidence suggested that glycogen synthase kinase-3β (GSK-3β) is involved in Nogo-66 inhibiting axonal regeneration in vitro, but its effect in vivo was poorly understood. We showed that stereotactic injection of shRNA GSK-3β-adeno associated virus (GSK-3β-AAV) diminished syringomyelia and promoted axonal regeneration after spinal cord injury (SCI), using stereotactic injection of shRNA GSK-3β-AAV (tested with Western blotting and RT-PCR) into the sensorimotor cortex of rats with SCI and by the detection of biotin dextran amine (BDA)-labeled axonal regeneration. We also determined the right position to inject into the sensorimotor cortex. Our findings consolidate the hypothesis that downregulation of GSK-3β promotes axonal regeneration after SCI.
Animals ; Axons ; drug effects ; metabolism ; Dependovirus ; genetics ; Glycogen Synthase Kinase 3 beta ; genetics ; metabolism ; Humans ; Nerve Regeneration ; genetics ; RNA, Small Interfering ; administration & dosage ; genetics ; Rats ; Sensorimotor Cortex ; drug effects ; pathology ; Spinal Cord Injuries ; genetics ; pathology ; therapy ; Syringomyelia ; genetics ; pathology ; therapy

OBJECTIVETo observe the deregulation of autophagy in diabetic peripheral neuropathy (DPN) and investigate whether Jinmaitong ( JMT) alleviates DPN by inducing autophagy.

METHODSDPN models were established by streptozotocin-induced diabetic rats and Schwann cells (SCs) cultured in high glucose medium. The pathological morphology was observed by the improved Bielschowsky's nerve fiber axonal staining and the Luxol fast blue-neutral red myelin staining. The ultrastructure was observed by the transmission electron microscopy. Beclin1 level was detected by immunohistochemistry and Western blot. The proliferation of cultured SCs was detected by methylthiazolyldiphenyl-tetrazolium bromide.

RESULTSDiabetic peripheral nerve tissues demonstrated pathological morphology and reduced autophagic structure, accompanied with down-regulation of Beclin1. JMT apparently alleviated the pathological morphology change and increased the autophagy [in vivo, Beclin1 integral optical density (IOD) value of the control group 86.6±17.7, DM 43.9±8.8, JMT 73.3 ±17.8, P<0.01 or P<0.05, in vitro Beclin1 IOD value of the glucose group 0.47±0.25 vs the control group 0.88±0.29, P<0.05]. Consequently, inhibition of autophagy by 3-methyladenine resulted in a time- and concentration-dependent decrease of the proliferation of SCs (P<0.05, P<0.01).

CONCLUSIONSDown-regulation of autophagy in SCs might contribute to the pathogenesis of DPN. JMT alleviates diabetic peripheral nerve injury at least in part by inducing autophagy.

Animals ; Autophagy ; drug effects ; Axons ; drug effects ; pathology ; Beclin-1 ; metabolism ; Cell Proliferation ; drug effects ; Cells, Cultured ; Diabetes Mellitus, Experimental ; complications ; drug therapy ; pathology ; Diabetic Neuropathies ; complications ; drug therapy ; pathology ; Down-Regulation ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Glucose ; pharmacology ; Immunohistochemistry ; Male ; Rats, Wistar ; Schwann Cells ; drug effects ; pathology ; Sciatic Nerve ; drug effects ; pathology ; ultrastructure ; Staining and Labeling

OBJECTIVETo study the ability of aqueous extract of Hericium erinaceus mushroom in the treatment of nerve injury following peroneal nerve crush in Sprague-Dawley rats.

METHODSAqueous extract of Hericium erinaceus was given by daily oral administration following peroneal nerve crush injury in Sprague-Dawley rats. The expression of protein kinase B (Akt) and mitogen-activated protein kinase (MAPK) signaling pathways; and c-Jun and c-Fos genes were studied in dorsal root ganglia (DRG) whereas the activity of protein synthesis was assessed in peroneal nerves by immunohistochemical method.

RESULTSPeripheral nerve injury leads to changes at the axonal site of injury and remotely located DRG containing cell bodies of sensory afferent neurons. Immunofluorescence studies showed that DRG neurons ipsilateral to the crush injury in rats of treated groups expressed higher immunoreactivities for Akt, MAPK, c-Jun and c-Fos as compared with negative control group (P <0.05). The intensity of nuclear ribonucleoprotein in the distal segments of crushed nerves of treated groups was significantly higher than in the negative control group (P <0.05).

CONCLUSIONH. erinaceus is capable of promoting peripheral nerve regeneration after injury. Potential signaling pathways include Akt, MAPK, c-Jun, and c-Fos, and protein synthesis have been shown to be involved in its action.

Agaricales ; chemistry ; Animals ; Axons ; pathology ; Female ; Ganglia, Spinal ; metabolism ; Glucans ; analysis ; MAP Kinase Signaling System ; Nerve Crush ; Nerve Regeneration ; physiology ; Peripheral Nerves ; enzymology ; physiology ; Peroneal Nerve ; physiology ; Protein Biosynthesis ; Proto-Oncogene Proteins c-akt ; metabolism ; Proto-Oncogene Proteins c-fos ; genetics ; metabolism ; Proto-Oncogene Proteins c-jun ; genetics ; metabolism ; Rats, Sprague-Dawley