Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 20
Filter
Add more filters










Publication year range
1.
Brain Sci ; 13(4)2023 Mar 26.
Article in English | MEDLINE | ID: mdl-37190523

ABSTRACT

BACKGROUND: Peripheral nerve decompression microsurgery can relieve nerve entrapment and improve the symptoms of DPN. However, postoperative tissue adhesion will produce new pressure on the nerves, affecting the surgical efficacy. In this study, a nerve conduit was used in the peripheral nerve decompression microsurgery to prevent postoperative adhesions, and the role of the nerve conduit in surgical nerve decompression was explored. METHODS: A total of 69 patients with DPN were recruited and randomly divided into three groups: the nerve conduit group, conventional surgery group, and control group. Two weeks before surgery and 6 months after surgery, patients in each group were clinically tested using the visual analog scale (VAS) score, neurophysiological test, Toronto clinical scoring system (TCSS) score, and two-point discrimination (2-PD) test. RESULTS: The patients' symptoms in the nerve conduit group were relieved to varying degrees, and the relief rate reached 90.9%; the treatment efficacy was higher than that in the other groups. The postoperative nerve conduction velocity (NCV) in the two surgical groups was significantly higher than that before the surgery, and the difference between the nerve conduit group and the conventional surgery group was statistically significant (p < 0.05). For the 2-PD test, there was a statistically significant difference between the two surgical groups (p < 0.05). The TCSS score in the two surgical groups was significantly higher than that in the control group (p < 0.01). There was a significant difference in the TCSS scores between the nerve conduit group and the conventional surgery group (p < 0.05). CONCLUSIONS: The nerve conduit could further improve the efficacy of peripheral nerve decompression microsurgery in the treatment of DPN.

2.
Int Immunopharmacol ; 113(Pt A): 109284, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36279673

ABSTRACT

Nerve injury-induced neuropathic pain is a type of chronic pain associated with neuroinflammatory response and neuronal death; however the underlying molecular mechanisms are still unclear. Dual-specificity phosphatase 8 (DUSP8) can mediate numerous cellular events, but whether it's involved in neuropathic pain is unknown. In the study, we found that spinal nerve ligation (SNL) operation on rats significantly decreased DUSP8 expression levels in ipsilateral spinal cord (ISC) tissues. Consistently, lipopolysaccharide (LPS) exposure also reduced DUSP8 in murine microglial cells. Adeno-associated virus (AAV)-mediated DUSP8 over-expression was found to considerably ameliorate SNL-induced neuropathic pain in rats. Additionally, neuronal death in the ISC tissues was also attenuated by AAV-DUSP8 following SNL surgery. Moreover, SNL-triggered neuroinflammation and microglial activation were also mitigated upon DUSP8 over-expression by suppressing nuclear factor κB (NF-κB) signaling, which were validated in LPS-exposed microglial cells. Importantly, our in vitro experiments indicated that inflammatory response in microglial cells contributed to neuron death, and such effect could also be ameliorated by DUSP8 over-expression. Notably, we found that DUSP8 directly interacted with transforming growth factor ß activated kinase-1 (TAK1) in microglial cells. Both SNL and LPS led to the activation of TAK1/p38/JNK1/2 signaling, whereas being strongly abolished by DUSP8. Intriguingly, TAK1 blockage significantly diminished LPS-induced inflammation and neuron death, whereas being accelerated by DUSP8 knockdown, further indicating that DUSP8-ameliorated neuropathic pain was largely TAK1-dependent. Together, all our findings revealed that DUSP8/TAK1 signaling may be a potential target for neuropathic pain alleviation.


Subject(s)
Dual-Specificity Phosphatases , MAP Kinase Kinase Kinases , Neuralgia , Animals , Mice , Rats , Dual-Specificity Phosphatases/metabolism , Hyperalgesia/metabolism , Inflammation/metabolism , Ligation , Lipopolysaccharides , Neuralgia/metabolism , Neuroinflammatory Diseases , Neurons/metabolism , Rats, Sprague-Dawley , Spinal Cord , Spinal Nerves/surgery , MAP Kinase Kinase Kinases/metabolism
3.
Front Mol Neurosci ; 15: 856299, 2022.
Article in English | MEDLINE | ID: mdl-35668789

ABSTRACT

Mechanical allodynia (MA) is the main reason that patients with diabetic peripheral neuropathy (DPN) seek medical advice. It severely debilitates the quality of life. Investigating hyperglycemia-induced changes in neural transcription could provide fundamental insights into the complex pathogenesis of painful DPN (PDPN). Gene expression profiles of physiological dorsal root ganglia (DRG) have been studied. However, the transcriptomic changes in DRG neurons in PDPN remain largely unexplored. In this study, by single-cell RNA sequencing on dissociated rat DRG, we identified five physiological neuron types and a novel neuron type MAAC (Fxyd7 + /Atp1b1 +) in PDPN. The novel neuron type originated from peptidergic neuron cluster and was characterized by highly expressing genes related to neurofilament and cytoskeleton. Based on the inferred gene regulatory networks, we found that activated transcription factors Hobx7 and Larp1 in MAAC could enhance Atp1b1 expression. Moreover, we constructed the cellular communication network of MAAC and revealed its receptor-ligand pairs for transmitting signals with other cells. Our molecular investigation at single-cell resolution advances the understanding of the dynamic peripheral neuron changes and underlying molecular mechanisms during the development of PDPN.

4.
J Biomed Mater Res A ; 110(4): 788-796, 2022 04.
Article in English | MEDLINE | ID: mdl-34792847

ABSTRACT

It is critical to repair severed facial nerves, as lack of treatment may cause long-term motor and sensory impairments. Ciliary neurotrophic factor (CNTF) plays an important role in terms of enhancing nerve axon regrowth and maturation during peripheral nerve regeneration after injury. However, simple application of CNTF to the transected nerve site does not afford functional recovery, because it is rapidly flushed away by bodily fluids. The aim of the present study was the construction of a new, bioactive composite nerve graft facilitating persistent CNTF delivery to aid the reconstruction of facial nerve defects. The in vitro study showed that the bioactive nerve graft generated sustainable CNTF release for more than 25 days. The bioactive nerve graft was then transplanted into the injury sites of rat facial nerves. At 6 and 12 weeks post-transplantation, functional and histological analyses showed that the bioactive nerve graft featuring immobilized CNTF significantly enhanced nerve regeneration in terms of both axonal outgrowth and Schwann cell proliferation in the rat facial nerve gap model, compared to a collagen tube with adsorbed CNTF that initially released high levels of CNTF. The bioactive nerve graft may serve as novel, controlled bioactive release therapy for facial nerve regeneration.


Subject(s)
Ciliary Neurotrophic Factor , Facial Nerve Injuries , Animals , Axons/physiology , Delayed-Action Preparations/pharmacology , Facial Nerve/pathology , Facial Nerve Injuries/pathology , Facial Nerve Injuries/therapy , Nerve Regeneration/physiology , Rats
5.
Sci Adv ; 6(22): eaay8627, 2020 05.
Article in English | MEDLINE | ID: mdl-32523984

ABSTRACT

To maintain brain homeostasis, a unique interface known as the blood-brain barrier (BBB) is formed between the blood circulation and the central nervous system (CNS). Major facilitator superfamily domain-containing 2a (Mfsd2a) is a specific marker of the BBB. However, the mechanism by which Mfsd2a influences the BBB is poorly understood. In this study, we demonstrated that Mfsd2a is essential for sphingosine-1-phosphate (S1P) export from endothelial cells in the brain. We found that Mfsd2a and Spinster homolog 2 (Spns2) form a protein complex to ensure the efficient transport of S1P. Furthermore, the S1P-rich microenvironment in the extracellular matrix (ECM) in the vascular endothelium dominates the formation and maintenance of the BBB. We demonstrated that different concentrations of S1P have different effects on BBB integrity. These findings help to unravel the mechanism by which S1P regulates BBB and also provide previously unidentified insights into the delivery of neurological drugs in the CNS.

6.
Nat Commun ; 11(1): 2163, 2020 05 01.
Article in English | MEDLINE | ID: mdl-32358530

ABSTRACT

Angiogenesis is a necessary process for solid tumor growth. Cellular markers for endothelial cell proliferation are potential targets for identifying the vasculature of tumors in homeostasis. Here we customize the behaviors of engineered cells to recognize Apj, a surface marker of the neovascular endothelium, using synthetic Notch (synNotch) receptors. We designed apelin-based synNotch receptors (AsNRs) that can specifically interact with Apj and then stimulate synNotch pathways. Cells engineered with AsNRs have the ability to sense the proliferation of endothelial cells (ECs). Designed for different synNotch pathways, engineered cells express different proteins to respond to angiogenic signals; therefore, angiogenesis can be detected by cells engineered with AsNRs. Furthermore, T cells customized with AsNRs can sense the proliferation of vascular endothelial cells. As solid tumors generally require vascular support, AsNRs are potential tools for the detection and therapy of a variety of solid tumors in adults.


Subject(s)
Apelin/chemistry , Apelin/metabolism , Neovascularization, Pathologic/metabolism , Receptors, Notch/chemistry , Receptors, Notch/metabolism , Animals , Apelin Receptors/metabolism , Blotting, Western , CD4-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/metabolism , Cell Proliferation/physiology , Endothelial Cells/metabolism , Flow Cytometry , HEK293 Cells , Human Umbilical Vein Endothelial Cells , Humans , Immunotherapy , Male , Mice , Mice, Inbred C57BL
7.
Stem Cells Dev ; 29(4): 235-248, 2020 02 15.
Article in English | MEDLINE | ID: mdl-31797735

ABSTRACT

Glial scars formed after brain injuries provide permissive cues for endogenous neural precursor/stem cells (eNP/SCs) to undergo astrogenesis rather than neurogenesis. Following brain injury, eNP/SCs from the subventricular zone leave their niche, migrate to the injured cortex, and differentiate into reactive astrocytes that contribute to glial scar formation. In vivo neuronal reprogramming, directly converting non-neuronal cells such as reactive astrocytes or NG2 glia into neurons, has greatly improved brain injury repair strategies. However, reprogramming carries a high risk of future clinical applications such as tumorigenicity, involving virus. In this study, we constructed a neural matrix to alter the adverse niche at the injured cortex, enabling eNP/SCs to differentiate into functional neurons. We found that the neural matrix functioned as a "glial trap" that largely concentrated and limited reactive astrocytes to the core of the lesion area, thus altering the adverse niche. The eNP/SCs migrated toward the injured cortex and differentiated into functional neurons. In addition, regenerated neurites extended across the boundary of the injured cortex. Mice treated with the neural matrix demonstrated significant behavioral recovery. For the first time, we induced eNP/SC-derived functional neurons in the cortex after brain injury without the use of viruses, microRNAs, or small molecules. Our novel strategy of applying this "glial trap" to obtain functional neurons in the injured cortex may provide a safer and more natural therapeutic alternative to reprogramming in future clinical applications.


Subject(s)
Brain Injuries, Traumatic/drug therapy , Cellular Reprogramming/drug effects , Cerebral Cortex/drug effects , Neurogenesis/drug effects , Neurons/drug effects , Animals , Brain Injuries, Traumatic/metabolism , Brain Injuries, Traumatic/pathology , Brain-Derived Neurotrophic Factor/chemistry , Brain-Derived Neurotrophic Factor/pharmacology , Cell Differentiation/drug effects , Cell Movement/drug effects , Cerebral Cortex/metabolism , Cerebral Cortex/pathology , Chemokine CXCL12/chemistry , Chemokine CXCL12/pharmacology , Chondroitin ABC Lyase/chemistry , Chondroitin ABC Lyase/pharmacology , Disease Models, Animal , Immobilized Proteins/chemistry , Immobilized Proteins/pharmacology , Lateral Ventricles/cytology , Lateral Ventricles/physiology , Maze Learning/physiology , Mice , Mice, Transgenic , Nerve Growth Factor/chemistry , Nerve Growth Factor/pharmacology , Neural Stem Cells/cytology , Neural Stem Cells/drug effects , Neural Stem Cells/physiology , Neurogenesis/physiology , Neuroglia/cytology , Neuroglia/drug effects , Neuroglia/physiology , Neurons/cytology , Neurons/physiology , Olfactory Bulb/cytology , Olfactory Bulb/physiology , Rotarod Performance Test , Stem Cell Niche/drug effects
8.
Brain Res ; 1721: 146321, 2019 10 15.
Article in English | MEDLINE | ID: mdl-31278935

ABSTRACT

Transplantation with mesenchymal stem cells (MSCs) has shown beneficial effects in treating spinal cord injury. Autophagy is an evolutionarily conserved process of degradation and recycling of cellular components that plays an important role in tissue homeostasis and cellular survival. Whether regulating autophagy in MSCs may affect their therapeutic potential in spinal cord injury repair has not yet been determined. In this study, autophagy was inhibited in MSCs with lentiviruses expressing short hairpin RNA (shRNA) to knock down Becn-1 expression, and autophagy was upregulated in MSCs under nutrient starvation. These MSCs were then labelled with Hoechst and applied to spinal cord-injured rats to evaluate their therapeutic effects. After transplanting MSCs into rats with spinal cord injuries, functional recovery, immunohistochemistry, and remyelination analyses were performed. After inducing autophagy, the MSCs exhibited an accumulation of LC3-positive autophagosomes in the cytoplasm. The expression levels of neurotrophic factors, including vascular endothelial growth factor and brain derived neurotrophic factor, were significantly higher in autophagic MSCs than normal MSCs. The in vivo study showed that more labelled MSCs migrated to the lesion site after induction of autophagy. Inducing autophagy in MSCs promoted functional recovery after spinal cord injury, whereas functional recovery was weak after inhibiting autophagy in MSCs. In contrast to the autophagy inhibition group, transplanting autophagic MSCs exhibited a greater positive impact on axon regeneration, growth of serotonergic fibers, blood vessel regeneration, and myelination, indicating a multifactorial contribution to spinal cord injury repair. These results suggest that autophagy plays important roles in MSCs during spinal cord injury repair. Regulation of autophagy in MSCs before in vivo transplantation may be a potential therapeutic interventional strategy for spinal cord injury.


Subject(s)
Autophagy/physiology , Mesenchymal Stem Cells/metabolism , Spinal Cord Injuries/therapy , Animals , Autophagy/genetics , Axons/pathology , Beclin-1/genetics , Beclin-1/metabolism , Female , Mesenchymal Stem Cell Transplantation/methods , Rats , Rats, Sprague-Dawley , Recovery of Function/genetics , Recovery of Function/physiology , Spinal Cord/metabolism , Spinal Cord Injuries/metabolism , Spinal Cord Regeneration/physiology , Vascular Endothelial Growth Factor A/metabolism
9.
Neuropsychiatr Dis Treat ; 15: 1211-1229, 2019.
Article in English | MEDLINE | ID: mdl-31190828

ABSTRACT

Background: Stress-related obesity might be related to the suppression of the hypothalamic-pituitary- adrenocortical axis and dysregulation of the metabolic system. Chronic stress also induces the dysregulation of the reward system and increases the risk of food addiction, according to recent clinical findings. However, few studies have tested the effect of chronic stress on food addiction in animal models. Purpose: The objective of this study was to identify whether chronic stress promotes food addiction or not and explore the possible mechanisms. Method: We applied adaily 2 hrsflashing LED irradiation stress to mice fed chow or palatable food to mimic the effect of chronic stress on feeding. After 1 month of chronic stress exposure, we tested their binge eating behaviors, cravings for palatable food, responses for palatable food, and compulsive eating behaviors to evaluate the effect of chronic stress on food addiction-like behaviors. We detected changes in the levels of various genes and proteins in the nucleus accumbens (NAc), ventral tegmental area (VTA) and lateral hypothalamus using qPCR and immunofluorescence staining, respectively. Results: Behaviors results indicated chronic stress obviously increased food addiction score (FAS) in the palatable food feeding mice. Moreover, the FAS had astrong relationship with the extent of the increase in body weight. Chronic stress increased the expression of corticotropin-releasing factor receptor 1(CRFR1) was increased in the NAc shell and core but decreased in the VTA of the mice fed with palatable food. Chronic stress also increased expression of both dopamine receptor 2 (DR2) and mu-opioid receptor (MOR) in the NAc. Conclusion: Chronic stress aggravates the FAS and contributed to the development of stress-related obesity. Chronic stress drives the dysregulation of the CRF signaling pathway in the reward system and increases the expression of DR2 and MOR in the nucleus accumbens.

10.
Int Immunopharmacol ; 72: 48-54, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30959371

ABSTRACT

Oxidative stress is considered as major culprit for neurodegenerative diseases and triggers cognitive and memory impairments. The present study mainly aimed to study the protective effects and underlying mechanisms of aloin on d-galactose (d-gal) induced ageing mice. Our results demonstrated that chronic administration of d-gal (150 mg kg-1) in mice caused spontaneous and cognitive impairments, as determined by open-field test and Morris water-maze test. Aloin treatment significantly ameliorated histopathological damage, attenuated the microglia activation and reduced levels of inflammatory mediators, such as tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and IL-6 in the hippocampus. Moreover, it effectively suppressed the level of reactive oxygen species (ROS) and increased antioxidant enzymes activities. Further data showed that these protective effects were accompanied by inhibition of the activation of nuclear factor kappa B and the phosphorylation of p38 and ERK. In conclusion, the present study suggests that aloin can ameliorate d-gal induced oxidative stress, cognitive impairment and inflammation, possibly via mediating the ERK, p38 and NF-κB signaling pathways.


Subject(s)
Cognitive Dysfunction/drug therapy , Emodin/analogs & derivatives , MAP Kinase Signaling System/drug effects , NF-kappa B/metabolism , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Animals , Brain/drug effects , Brain/metabolism , Brain/pathology , Cognitive Dysfunction/chemically induced , Cognitive Dysfunction/metabolism , Cognitive Dysfunction/pathology , Cytokines/metabolism , Down-Regulation/drug effects , Emodin/pharmacology , Emodin/therapeutic use , Galactose , Glutathione/metabolism , Male , Maze Learning/drug effects , Mice, Inbred C57BL , Oxidative Stress/drug effects , Superoxide Dismutase/metabolism
11.
Bioconjug Chem ; 29(11): 3561-3570, 2018 11 21.
Article in English | MEDLINE | ID: mdl-30371055

ABSTRACT

Neural stem cells (NSCs) have been attractive donor sources for cell therapy in traumatic brain injuries (TBI). Monitoring the fate of transplanted cells, including the survival and differentiation, will provide vital information to assess the outcome during the therapy time course. However, the current labeling methods are based on the principles of cell endocytosis, demanding relatively high fluorescent probes concentration and long incubation time, which may affect the proliferation and differentiation of transplanted cells. In our study, an efficient and relatively fast labeling strategy for NSCs with Cy3 based on DNA hybridization was proposed for monitoring the fate of transplanted cells. The oligo[dA]20 conjugated with Cy3 was anchored on NSCs which had modified with oligo[dT]20 via the oligo[dT]20-oligo[dA]20 hybridization. This labeling system did not affect the viability of labeled NSCs. After implantation of labeled NSCs into the brain, immunohistology demonstrated implanted cells were able to survive and differentiate into mature neural cells as long as one month. In conclusion, the DNA hybridization system can be used as an efficient cell labeling method in cell therapy.


Subject(s)
Carbocyanines/chemistry , Cell Differentiation , Cell Survival , DNA/chemistry , Neural Stem Cells/cytology , Nucleic Acid Hybridization , Animals , Brain Injuries, Traumatic/therapy , Disease Models, Animal , Mice , Stem Cell Transplantation
12.
Organogenesis ; 14(3): 123-128, 2018.
Article in English | MEDLINE | ID: mdl-30148412

ABSTRACT

Nervous system injury represent the most common injury and was unique clinical challenge. Using of growth factors (GFs) for the treatment of nervous system injury showed effectiveness in halting its process. However, simple application of GFs could not achieve high efficacy because of its rapid diffusion into body fluids and lost from the lesion site. The drug delivery systems (DDSs) construction used to deliver GFs were investigated so that they could surmount its rapid diffusion and retain at the injury site. This study summarizes commonly used DDSs for sustained release of GFs that provide neuroprotection or restoration effects for nervous system injury.


Subject(s)
Drug Delivery Systems , Intercellular Signaling Peptides and Proteins/administration & dosage , Intercellular Signaling Peptides and Proteins/therapeutic use , Trauma, Nervous System/drug therapy , Animals , Biocompatible Materials , Delayed-Action Preparations/administration & dosage , Delayed-Action Preparations/therapeutic use , Humans , Immobilized Proteins/administration & dosage , Immobilized Proteins/therapeutic use
13.
Acta Biomater ; 69: 146-155, 2018 03 15.
Article in English | MEDLINE | ID: mdl-29330037

ABSTRACT

Facial nerve injury caused by traffic accidents or operations may reduce the quality of life in patients, and recovery following the injury presents unique clinical challenges. Glial cell-derived neurotrophic factor (GDNF) is important in nerve regeneration; however, soluble GDNF rapidly diffuses into body fluids, making it difficult to achieve therapeutic efficacy. In this work, we developed a rat tail derived collagen conduit to connect nerve defects in a simple and safe manner. GDNF was immobilized in the collagen conduits via chemical conjugation to enable controlled release of GDNF. The GDNF delivery system prevented rapid diffusion from the site without impacting bioactivity of GDNF; degradation of the collagen conduit was inhibited owing to the chemical conjugation. The artificial nerve conduit was then used to examine facial nerve regeneration across a facial nerve defect. Following transplantation, the artificial nerve conduits degraded gradually without causing dislocations and serious inflammation, with good integration into the host tissue. Functional and histological tests indicated that the artificial nerve conduits were able to guide the axons to grow through the defect, reaching the distal stumps. The degree of nerve regeneration in the group that was treated with the artificial nerve conduit approached that of the autograft group, and exceeded that of the other conduit grafted groups. STATEMENT OF SIGNIFICANCE: In this study, we developed artificial nerve conduits consisting of GDNF immobilized on collagen, with the aim of providing an environment for nerve regeneration. Our results show that the artificial nerve conduits guided the regeneration of axons to the distal nerve segment. GDNF was immobilized stably in the artificial nerve conduits, and therefore retained a sufficient concentration at the target site to effectively promote the regeneration process. The artificial nerve conduits exhibited good biocompatibility and facilitated nerve regeneration and functional recovery with an efficacy that was close to that of an autograft, and better than that of the other conduit grafted groups. Our approach provides an effective delivery system that overcomes the rapid diffusion of GDNF in body fluids, promoting peripheral nerve regeneration. The artificial nerve conduit therefore qualifies as a putative candidate material for the fabrication of peripheral nerve reconstruction devices.


Subject(s)
Absorbable Implants , Collagen , Facial Nerve Injuries/therapy , Facial Nerve/physiology , Glial Cell Line-Derived Neurotrophic Factor , Nerve Regeneration/drug effects , Animals , Collagen/chemistry , Collagen/pharmacokinetics , Collagen/pharmacology , Drug Implants/chemistry , Drug Implants/pharmacokinetics , Drug Implants/pharmacology , Facial Nerve Injuries/metabolism , Facial Nerve Injuries/pathology , Female , Glial Cell Line-Derived Neurotrophic Factor/chemistry , Glial Cell Line-Derived Neurotrophic Factor/pharmacokinetics , Glial Cell Line-Derived Neurotrophic Factor/pharmacology , Rats , Rats, Sprague-Dawley
14.
Stem Cells Int ; 2017: 2934149, 2017.
Article in English | MEDLINE | ID: mdl-29138636

ABSTRACT

The growing field of stem cell therapy is moving toward clinical trials in a variety of applications, particularly for neurological diseases. However, this translation of cell therapies into humans has prompted a need to create innovative and breakthrough methods for stem cell tracing, to explore the migration routes and its reciprocity with microenvironment targets in the body, to monitor and track the outcome after stem cell transplantation therapy, and to track the distribution and cell viability of transplanted cells noninvasively and longitudinally. Recently, a larger number of cell tracking methods in vivo were developed and applied in animals and humans, including magnetic resonance imaging, nuclear medicine imaging, and optical imaging. This review has been intended to summarize the current use of those imaging tools in tracking stem cells, detailing their main features and drawbacks, including image resolution, tissue penetrating depth, and biosafety aspects. Finally, we address that multimodality imaging method will be a more potential tracking tool in the future clinical application.

15.
Acta Biomater ; 50: 188-197, 2017 03 01.
Article in English | MEDLINE | ID: mdl-27940160

ABSTRACT

Introducing neural stem/progenitor cells (NS/PCs) for repairing facial nerve injuries could be an alternative strategy for nerve gap reconstruction. However, the lack of success associated with current methods of applying NS/PCs to neurological disease is due to poor engraftment following transplantation into the host tissue. In this work, we developed rat-tail collagen-based nerve conduits to repair lengthy facial nerve defects, promoting NS/PC proliferation in the natural nerve conduits with anchored bFGF to improve the therapeutic effects of cell transplantation. In vitro studies showed that heparinized collagen prevented leakage of bFGF and NS/PCs expended in the rat-tail collagen gel with the anchored bFGF. The natural nerve conduits were implanted to connect 8-mm facial nerve defects in rats. The repair outcomes including vibrissae movements, electrophysiological tests, immunohistochemistry and remyelination analysis of regenerated nerve were evaluated. At 12weeks after implantation, only natural nerve conduits treated group showed Hoechst labeled NS/PCs. Besides, the natural nerve conduit significantly promoted functional recovery and nerve growth, which was similar to those of the gold standard, an autograft. The animal experiment results suggesting that the natural nerve conduits were valuable for facial nerve reconstruction. STATEMENT OF SIGNIFICANCE: Neural stem/progenitor cells (NS/PCs) were beneficial for the treatment of nervous system diseases. However, after transplantation, the beneficial was limited because the number of living NS/PCs decreased rapidly due to insufficient signaling molecules, such as growth factors, in the microenvironments surrounding transplanted cells. In the present study, we constructed collagen-based nerve conduit with anchored bFGF to achieve higher numbers of NS/PCs for repairing facial nerve injury. Compared with other methods involving neutral salt treatment or dialysis, the fabrication method of collagen scaffolds was simple, low-cost and safe, requiring a relatively short time to prepare. At 12weeks after transplantation, the functional and histological results of natural nerve conduits treated group showed significant similarities to the gold standard method of nerve autografting.


Subject(s)
Collagen , Facial Nerve Injuries/therapy , Facial Nerve/physiology , Fibroblast Growth Factor 2 , Nerve Regeneration/drug effects , Neural Stem Cells/metabolism , Animals , Collagen/chemistry , Collagen/pharmacology , Facial Nerve Injuries/metabolism , Female , Fibroblast Growth Factor 2/chemistry , Fibroblast Growth Factor 2/pharmacology , Rats , Rats, Sprague-Dawley
16.
Int J Mol Sci ; 15(10): 18593-609, 2014 Oct 15.
Article in English | MEDLINE | ID: mdl-25322152

ABSTRACT

The search for effective strategies for peripheral nerve regeneration has attracted much attention in recent years. In this study, ordered collagen fibers were used as intraluminal fibers after nerve injury in rats. Vascular endothelial growth factor (VEGF) plays an important role in nerve regeneration, but its very fast initial burst of activity within a short time has largely limited its clinical use. For the stable binding of VEGF to ordered collagen fibers, we fused a collagen-binding domain (CBD) to VEGF through recombinant DNA technology. Then, we filled the ordered collagen fibers-CBD-VEGF targeting delivery system in a collagen tube to construct natural neural scaffolds, which were then used to bridge transected nerve stumps in a rat sciatic nerve transection model. After transplantation, the natural neural scaffolds showed minimal foreign body reactions and good integration into the host tissue. Oriented collagen fibers in the collagen tube could guide regenerating axons in an oriented manner to the distal, degenerating nerve segment, maximizing the chance of target reinnervation. Functional and histological analyses indicated that the recovery of nerve function in the natural neural scaffolds-treated group was superior to the other grafted groups. The guiding of oriented axonal regeneration and effective delivery systems surmounting the otherwise rapid and short-lived diffusion of growth factors in body fluids are two important strategies in promoting peripheral nerve regeneration. The natural neural scaffolds described take advantage of these two aspects and may produce synergistic effects. These properties qualified the artificial nerve conduits as a putative candidate system for the fabrication of peripheral nerve reconstruction devices.


Subject(s)
Collagen/chemistry , Nerve Regeneration/drug effects , Sciatic Nerve/physiology , Tissue Scaffolds/chemistry , Vascular Endothelial Growth Factor A/administration & dosage , Animals , Female , Immobilized Proteins/administration & dosage , Immobilized Proteins/therapeutic use , Rats , Rats, Sprague-Dawley , Sciatic Nerve/drug effects , Vascular Endothelial Growth Factor A/therapeutic use
17.
Biomacromolecules ; 15(3): 1062-8, 2014 Mar 10.
Article in English | MEDLINE | ID: mdl-24527809

ABSTRACT

Neural stem/progenitor cells (NS/PCs) play a therapeutic role in nervous system diseases and contribute to functional recovery. However, their efficacy is limited as the majority of cells die post-transplantation. In this study, collagen sponges were utilized as carriers for NS/PCs. Basic fibroblast growth factor (bFGF), a mitogen for NS/PCs, was incorporated into the collagen sponges to stimulate NS/PC proliferation. However, the effect of native bFGF is limited because it diffuses into the culture medium and is lost following medium exchange. To overcome this problem, a collagen-binding polypeptide domain, which has high affinity to collagen, was fused with bFGF to sustain the exposure of NS/PCs within the collagen sponges to bFGF. The results indicated that the number of NS/PCs was significantly higher in collagen sponges incorporating engineered bFGF than in those with native bFGF or the PBS control after 7 days in culture. Here, we designed a natural biological neural scaffold consisting of collagen sponges, engineered bFGF, and NS/PCs. In addition to the effect of proliferated NS/PCs, the engineered bFGF retained in the natural biological neural scaffolds could have a direct effect on nervous system reconstruction. The two aspects of the natural biological neural scaffolds may produce synergistic effects, and so they represent a promising candidate for nervous system repair.


Subject(s)
Fibroblast Growth Factors/administration & dosage , Nervous System/drug effects , Neural Stem Cells/cytology , Tissue Engineering , Animals , Cell Differentiation/genetics , Cell Proliferation/drug effects , Collagen/chemistry , Culture Media , Fibroblast Growth Factors/chemistry , Humans , Microscopy, Electron, Scanning , Neural Stem Cells/metabolism , Rats , Tissue Scaffolds/chemistry
18.
Tissue Eng Part A ; 20(7-8): 1253-62, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24188561

ABSTRACT

Natural biological functional scaffolds, consisting of biological materials filled with promoting elements, provide a promising strategy for the regeneration of peripheral nerve defects. Collagen conduits have been used widely due to their excellent biological properties. Linear ordered collagen scaffold (LOCS) fibers are good lumen fillers that can guide nerve regeneration in an ordered direction. In addition, basic fibroblast growth factor (bFGF) is important in the recovery of nerve injury. However, the traditional method for delivering bFGF to the lesion site has no long-term effect because of its short half-life and rapid diffusion. Therefore, we fused a specific collagen-binding domain (CBD) peptide to the N-terminal of native basic fibroblast growth factor (NAT-bFGF) to retain bFGF on the collagen scaffolds. In this study, a natural biological functional scaffold was constructed using collagen tubes filled with collagen-binding bFGF (CBD-bFGF)-loaded LOCS to promote regeneration in a 5-mm rat sciatic nerve transection model. Functional evaluation, histological investigation, and morphometric analysis indicated that the natural biological functional scaffold retained more bFGF at the injury site, guided axon growth, and promoted nerve regeneration as well as functional restoration.


Subject(s)
Collagen/chemistry , Collagen/pharmacology , Fibroblast Growth Factor 2/pharmacology , Nerve Regeneration/drug effects , Sciatic Nerve/injuries , Sciatic Nerve/physiopathology , Tissue Scaffolds/chemistry , Animals , Cattle , Electrophysiological Phenomena/drug effects , Fibroblast Growth Factor 2/chemistry , Fibroblast Growth Factor 2/metabolism , Male , Muscles/drug effects , Muscles/pathology , Organ Size/drug effects , Protein Binding/drug effects , Protein Structure, Tertiary , Rats , Recovery of Function/drug effects , Sciatic Nerve/surgery , Sciatic Nerve/transplantation , Stilbamidines/metabolism
19.
Biomaterials ; 34(21): 5107-16, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23591390

ABSTRACT

The main challenge for neural progenitor cell (NPC)-mediated repair of spinal cord injury (SCI) is lack of favorable environment to direct its differentiation towards neurons rather than glial cells. The myelin associated inhibitors have been demonstrated to promote NPC differentiation into glial lineage. Herein, to inhibit the downstream signaling activated by myelin associated inhibitors, cetuximab, an epidermal growth factor receptor (EGFR) neutralizing antibody, functionalized collagen scaffold has been developed as a vehicle for NPC implantation. It was found that collagen-cetuximab 1 µg scaffolds enhanced neuronal differentiation and inhibited astrocytic differentiation of NPCs exposed to myelin proteins significantly in vitro. To test the therapeutic effect in vivo, NPCs expressing green fluorescent protein (GFP)-embedded scaffolds have been implanted into the 4 mm-long hemisection lesion of rats. We found that the collagen-cetuximab 5 µg scaffolds induced neuronal differentiation and decreased astrocytic differentiation of NPCs, enhanced axon regeneration, and promoted functional recovery markedly. A well-functionalized scaffold was constructed to improve the recovery of SCI, which could promote the neuronal differentiation of neural progenitor cells in vivo.


Subject(s)
Antibodies/pharmacology , Cell Differentiation/drug effects , Collagen/pharmacology , ErbB Receptors/immunology , Neural Stem Cells/cytology , Neurons/cytology , Spinal Cord Injuries/therapy , Animals , Antibodies, Monoclonal, Humanized/pharmacology , Astrocytes/cytology , Astrocytes/drug effects , Astrocytes/metabolism , Cell Count , Cetuximab , ErbB Receptors/antagonists & inhibitors , Green Fluorescent Proteins/metabolism , Mice , Neural Stem Cells/drug effects , Neural Stem Cells/transplantation , Neurons/drug effects , Neurons/metabolism , Rats , Rats, Sprague-Dawley , Recovery of Function/drug effects , Spinal Cord Injuries/pathology , Spinal Cord Injuries/physiopathology , Spinal Cord Regeneration/drug effects , Stem Cell Transplantation , Tissue Scaffolds/chemistry
20.
Shanghai Kou Qiang Yi Xue ; 13(4): 348-9, 2004 Aug.
Article in Chinese | MEDLINE | ID: mdl-15349687

ABSTRACT

To study the clinical effect of catechu on oral lichen planus of erosion type.100 patients with erosive oral lichen planus were divided randomly into two groups. The experimental group were treated with catechu while the control group were treated routinely with tripterygium hypoglaucum hutch tablet. The patients in two groups underwent 2 to 3 terms of treatment respectively. The results of patients in the experimental group was significantly better than that of the control group.


Subject(s)
Drugs, Chinese Herbal/therapeutic use , Lichen Planus, Oral/drug therapy , Phytotherapy , Adult , Female , Humans , Male , Middle Aged
SELECTION OF CITATIONS
SEARCH DETAIL
...