1
|
Li D, Yang Q, Liu X, Jia J, Liu G, Bai K, Jia S, Peng J, Yu F. Experimental study on the repair of peripheral nerve injuries via simultaneously coapting the proximal and distal ends of peripheral nerves to the side of nearby intact nerves. Front Neurol 2023; 14:1088983. [PMID: 37090979 PMCID: PMC10115955 DOI: 10.3389/fneur.2023.1088983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 03/20/2023] [Indexed: 04/08/2023] Open
Abstract
IntroductionPeripheral nerve defect is a difficult disease to treat in clinical practice. End-to-side anastomosis is a useful method to treat it. At present, the end-to-side anastomosis method does not involve the proximal nerve, which results in a waste of proximal donor nerves, and even the formation of traumatic neuromas at the proximal end. The patients suffer from traumatic neuralgia and the curative effect is unsatisfactory.MethodsIn this study, an improved end-to-side anastomosis technique was proposed in this study: both the proximal and distal ends of the damaged common peroneal nerve were sutured to an adjacent normal tibial nerve. Moreover, the possible role and mechanism of the proposed technique were explained at the physiological and anatomical levels. In this study, a 10 mm common peroneal nerve defect was made in SD rats, and the rats were randomly divided into three groups. In Group I, the distal end of the common peroneal nerve was attached end-to-side to the fenestrated tibial nerve adventitia, and the proximal end was ligated and fixed in the nearby muscle. In Group II, the tibial nerve adventitia was fenestrated and the epineurial end-to-end anastomosis surgery was performed to suture the proximal and distal ends of the common peroneal nerve. Rats in Group III were taken as control and received sham operation. Twelve weeks after the operation, the recovery of the repaired nerve and distal effector functions were examined by the sciatic functional index, electrophysiology, osmic acid staining, the muscle wet weight ratio, and the muscle fiber cross-sectional area.ResultsIt was found that these results in Group II were similar to those in Group III, but better than those in Group I. Through retrograde tracing of neurons and Electrophysiological examination in Group II, the study also found that the proximal common peroneal nerve also could establish a connection with tibialis anterior, even gastrocnemius.DiscussionTherefore, it is inferred that fostering both the proximal and distal ends of defective peripheral nerves on normal peripheral nerves using the end-to-side anastomosis technique is a more effective approach to repairing injured nerves.
Collapse
Affiliation(s)
- Dongdong Li
- Department of Orthopedics, Strategic Support Force Medical Center, Beijing, China
| | - Qi Yang
- Department of Ultrasonography, Peking University Shenzhen Hospital, Shenzhen, China
| | - Xin Liu
- Department of Orthopedics, Strategic Support Force Medical Center, Beijing, China
| | - Jing Jia
- Department of Orthopedics, Strategic Support Force Medical Center, Beijing, China
| | - Guangbo Liu
- Department of Orthopedics, Strategic Support Force Medical Center, Beijing, China
| | - Kewen Bai
- Department of Orthopedics, Strategic Support Force Medical Center, Beijing, China
| | - Shicheng Jia
- Department of Sports Medicine, Peking University Shenzhen Hospital, Shenzhen, China
| | - Jun Peng
- Department of Orthopedics, Strategic Support Force Medical Center, Beijing, China
- Jun Peng
| | - Fei Yu
- Department of Bone and Joint Surgery, Peking University Shenzhen Hospital, Shenzhen, China
- National and Local Joint Engineering Research Center of Orthopaedic Biomaterials, Peking University Shenzhen Hospital, Shenzhen, China
- *Correspondence: Fei Yu
| |
Collapse
|
2
|
Effects of Semaphorin3A on the growth of sensory and motor neurons. Exp Cell Res 2023; 424:113506. [PMID: 36764590 DOI: 10.1016/j.yexcr.2023.113506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 02/02/2023] [Accepted: 02/05/2023] [Indexed: 02/11/2023]
Abstract
After peripheral nerve injury, motor and sensory axons can regenerate, but the inaccurate reinnervation of the target leads to poor functional recovery. Schwann cells (SCs) express sensory and motor phenotypes associated with selective regeneration. Semaphorin 3A (Sema3A) is an axonal chemorepellent that plays an essential role in axon growth. SCs can secret Sema3A, and Sema3A presents a different expression pattern at the proximal and distal ends of injured sensory and motor nerves. Hence, in our study, the protein expression and secretion of Sema3A in sensory and motor SCs and the expression of its receptor Neuropilin-1 (Nrp1) in dorsal root ganglia (DRG) sensory neurons (SNs) and spinal cord motor neurons (MNs) were detected by Western blot and ELISA. The effect of Sema3A at different concentrations on neurite growth of sensory and motor neurons was observed by immunostaining. Also, by blocking the Nrp1 receptor on neurons, the effect of Sema3A on neurite growth was observed. Finally, we observed the neurite growth of sensory and motor neurons cocultured with Sema3A siRNA transfected SCs by immunostaining. The results suggested that the expression and secretion of Sema3A in sensory SCs are more significant than that in motor SCs, and the expression of its receptor Nrp1 in SNs is higher than in MNs. Sema3A could inhibit the neurite growth of sensory and motor neurons via Nrp1, and Sema3A has a more substantial effect on the neurite growth of SNs. These data provide evidence that SC-secreted Sema3A might play a role in selective regeneration by a preferential effect on SNs.
Collapse
|
3
|
Chen S, Gu X, Li R, An S, Wang Z. Genome-wide Analysis of Histone H3 Lysine 27 Trimethylation Profiles in Sciatic Nerve of Chronic Constriction Injury Rats. Neurochem Res 2023; 48:1945-1957. [PMID: 36763313 DOI: 10.1007/s11064-023-03879-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 01/12/2023] [Accepted: 01/28/2023] [Indexed: 02/11/2023]
Abstract
The histone H3 lysine 27 trimethylation (H3K27me3) is one of the most important chromatin modifications, which is associated with injury-activated gene expression in Schwann cells (SCs). However, the alteration of genome-wide H3K27me3 enrichments in the development of neuropathic pain is still unknown. Here, we applied the chromatin immunoprecipitation sequencing (ChIP-seq) approach to identify the alteration of differential enrichments of H3K27me3 in chronic constriction injury (CCI) sciatic nerve of rats and potential molecular mechanisms underlying the development of neuropathic pain. Our results indicated that CCI increased the numbers of SCs displaying H3K27 methyltransferase enhancer of zeste homolog 2 (EZH2) and H3K27me3 in the sciatic nerve. ChIP-seq data showed that CCI significantly changed H3K27me3 enrichments on gene promoters in the sciatic nerve. Bioinformatics analyses exhibited that genes gaining H3K27me3 were mostly associated with regulation of cell proliferation, response to stress and oxidation-reduction process. Genes losing this mark were enriched in neuronal generation, and MAPK, cAMP as well as ERBB signaling pathways. Importantly, IL1A, CCL2, NOS2, S100A8, BDNF, GDNF, ERBB3 and C3 were identified as key genes in neuropathic pain. CCI led to significant upregulation of key genes in the sciatic nerve. EZH2 inhibitor reversed CCI-induced increases of H3K27me3 and key gene protein levels, which were accompanied by relieved mechanical allodynia and thermal hyperalgesia in CCI rats. These results indicate that genes with differential enrichments of H3K27me3 in SCs function in various cellular processes and pathways, and many are linked to neuropathic pain after peripheral nerve injury.
Collapse
Affiliation(s)
- Shuhui Chen
- Department of Human Anatomy, Shandong First Medical University & Shandong Academy of Medical Sciences, 2 Ying Sheng Dong Lu, Taian, 271000, China
| | - Xinpei Gu
- Department of Human Anatomy, Shandong First Medical University & Shandong Academy of Medical Sciences, 2 Ying Sheng Dong Lu, Taian, 271000, China
| | - Ruidi Li
- Department of Human Anatomy, Shandong First Medical University & Shandong Academy of Medical Sciences, 2 Ying Sheng Dong Lu, Taian, 271000, China
| | - Shuhong An
- Department of Human Anatomy, Shandong First Medical University & Shandong Academy of Medical Sciences, 2 Ying Sheng Dong Lu, Taian, 271000, China.
| | - Zhaojin Wang
- Department of Human Anatomy, Shandong First Medical University & Shandong Academy of Medical Sciences, 2 Ying Sheng Dong Lu, Taian, 271000, China.
| |
Collapse
|
4
|
Li WY, Fu XM, Wang ZD, Li ZG, Ma D, Sun P, Liu GB, Zhu XF, Wang Y. Krüppel-like factor 7 attenuates hippocampal neuronal injury after traumatic brain injury. Neural Regen Res 2022; 17:661-672. [PMID: 34380908 PMCID: PMC8504401 DOI: 10.4103/1673-5374.320991] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/20/2021] [Accepted: 05/06/2021] [Indexed: 11/25/2022] Open
Abstract
Our previous study has shown that the transcription factor Krüppel-like factor 7 (KLF7) promotes peripheral nerve regeneration and motor function recovery after spinal cord injury. KLF7 also participates in traumatic brain injury, but its regulatory mechanisms remain poorly understood. In the present study, an HT22 cell model of traumatic brain injury was established by stretch injury and oxygen-glucose deprivation. These cells were then transfected with an adeno-associated virus carrying KLF7 (AAV-KLF7). The results revealed that, after stretch injury and oxygen-glucose deprivation, KLF7 greatly reduced apoptosis, activated caspase-3 and lactate dehydrogenase, downregulated the expression of the apoptotic markers B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax) and cleaved caspase-3, and increased the expression of βIII-tubulin and the antiapoptotic marker Bcl-2. Furthermore, KLF7 overexpression upregulated Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) phosphorylation in HT22 cells treated by stretch injury and oxygen-glucose deprivation. Immunoprecipitation assays revealed that KLF7 directly participated in the phosphorylation of STAT3. In addition, treatment with AG490, a selective inhibitor of JAK2/STAT3, weakened the protective effects of KLF7. A mouse controlled cortical impact model of traumatic brain injury was then established. At 30 minutes before modeling, AAV-KLF7 was injected into the ipsilateral lateral ventricle. The protein and mRNA levels of KLF7 in the hippocampus were increased at 1 day after injury and recovered to normal levels at 3 days after injury. KLF7 reduced ipsilateral hippocampal atrophy, decreased the injured cortex volume, downregulated Bax and cleaved caspase-3 expression, and increased the number of 5-bromo-2'-deoxyuridine-positive neurons and Bcl-2 protein expression. Moreover, KLF7 transfection greatly enhanced the phosphorylation of JAK2 and STAT3 in the ipsilateral hippocampus. These results suggest that KLF7 may protect hippocampal neurons after traumatic brain injury through activation of the JAK2/STAT3 signaling pathway. The study was approved by the Institutional Review Board of Mudanjiang Medical University, China (approval No. mdjyxy-2018-0012) on March 6, 2018.
Collapse
Affiliation(s)
- Wen-Yuan Li
- Institute of Neural Tissue Engineering, Mudanjiang Medical University, Mudanjiang, Heilongjiang Province, China
| | - Xiu-Mei Fu
- Department of Anatomy, College of Basic Medical Sciences, Chengde Medical University, Chengde, Hebei Province, China
- Hebei Key Laboratory of Nerve Injury and Repair, Chengde Medical University, Chengde, Hebei Province, China
| | - Zhen-Dong Wang
- Department of Otorhinolaryngology, Mudanjiang City Second People’s Hospital, Mudanjiang, Heilongjiang Province, China
| | - Zhi-Gang Li
- The First Department of General Surgery, Hongqi Hospital, Mudanjiang Medical University, Mudanjiang, Heilongjiang Province, China
| | - Duo Ma
- Institute of Neural Tissue Engineering, Mudanjiang Medical University, Mudanjiang, Heilongjiang Province, China
| | - Ping Sun
- Institute of Neural Tissue Engineering, Mudanjiang Medical University, Mudanjiang, Heilongjiang Province, China
| | - Gui-Bo Liu
- Institute of Neural Tissue Engineering, Mudanjiang Medical University, Mudanjiang, Heilongjiang Province, China
| | - Xiao-Feng Zhu
- Institute of Neural Tissue Engineering, Mudanjiang Medical University, Mudanjiang, Heilongjiang Province, China
| | - Ying Wang
- Institute of Neural Tissue Engineering, Mudanjiang Medical University, Mudanjiang, Heilongjiang Province, China
| |
Collapse
|
5
|
Cintron-Colon AF, Almeida-Alves G, VanGyseghem JM, Spitsbergen JM. GDNF to the rescue: GDNF delivery effects on motor neurons and nerves, and muscle re-innervation after peripheral nerve injuries. Neural Regen Res 2021; 17:748-753. [PMID: 34472460 PMCID: PMC8530131 DOI: 10.4103/1673-5374.322446] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Peripheral nerve injuries commonly occur due to trauma, like a traffic accident. Peripheral nerves get severed, causing motor neuron death and potential muscle atrophy. The current golden standard to treat peripheral nerve lesions, especially lesions with large (≥ 3 cm) nerve gaps, is the use of a nerve autograft or reimplantation in cases where nerve root avulsions occur. If not tended early, degeneration of motor neurons and loss of axon regeneration can occur, leading to loss of function. Although surgical procedures exist, patients often do not fully recover, and quality of life deteriorates. Peripheral nerves have limited regeneration, and it is usually mediated by Schwann cells and neurotrophic factors, like glial cell line-derived neurotrophic factor, as seen in Wallerian degeneration. Glial cell line-derived neurotrophic factor is a neurotrophic factor known to promote motor neuron survival and neurite outgrowth. Glial cell line-derived neurotrophic factor is upregulated in different forms of nerve injuries like axotomy, sciatic nerve crush, and compression, thus creating great interest to explore this protein as a potential treatment for peripheral nerve injuries. Exogenous glial cell line-derived neurotrophic factor has shown positive effects in regeneration and functional recovery when applied in experimental models of peripheral nerve injuries. In this review, we discuss the mechanism of repair provided by Schwann cells and upregulation of glial cell line-derived neurotrophic factor, the latest findings on the effects of glial cell line-derived neurotrophic factor in different types of peripheral nerve injuries, delivery systems, and complementary treatments (electrical muscle stimulation and exercise). Understanding and overcoming the challenges of proper timing and glial cell line-derived neurotrophic factor delivery is paramount to creating novel treatments to tend to peripheral nerve injuries to improve patients’ quality of life.
Collapse
Affiliation(s)
| | | | | | - John M Spitsbergen
- Biological Sciences Department, Western Michigan University, Kalamazoo, MI, USA
| |
Collapse
|
6
|
Schwann Cell Role in Selectivity of Nerve Regeneration. Cells 2020; 9:cells9092131. [PMID: 32962230 PMCID: PMC7563640 DOI: 10.3390/cells9092131] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 09/16/2020] [Accepted: 09/17/2020] [Indexed: 12/13/2022] Open
Abstract
Peripheral nerve injuries result in the loss of the motor, sensory and autonomic functions of the denervated segments of the body. Neurons can regenerate after peripheral axotomy, but inaccuracy in reinnervation causes a permanent loss of function that impairs complete recovery. Thus, understanding how regenerating axons respond to their environment and direct their growth is essential to improve the functional outcome of patients with nerve lesions. Schwann cells (SCs) play a crucial role in the regeneration process, but little is known about their contribution to specific reinnervation. Here, we review the mechanisms by which SCs can differentially influence the regeneration of motor and sensory axons. Mature SCs express modality-specific phenotypes that have been associated with the promotion of selective regeneration. These include molecular markers, such as L2/HNK-1 carbohydrate, which is differentially expressed in motor and sensory SCs, or the neurotrophic profile after denervation, which differs remarkably between SC modalities. Other important factors include several molecules implicated in axon-SC interaction. This cell–cell communication through adhesion (e.g., polysialic acid) and inhibitory molecules (e.g., MAG) contributes to guiding growing axons to their targets. As many of these factors can be modulated, further research will allow the design of new strategies to improve functional recovery after peripheral nerve injuries.
Collapse
|
7
|
Prautsch KM, Schmidt A, Paradiso V, Schaefer DJ, Guzman R, Kalbermatten DF, Madduri S. Modulation of Human Adipose Stem Cells' Neurotrophic Capacity Using a Variety of Growth Factors for Neural Tissue Engineering Applications: Axonal Growth, Transcriptional, and Phosphoproteomic Analyses In Vitro. Cells 2020; 9:E1939. [PMID: 32839392 PMCID: PMC7565501 DOI: 10.3390/cells9091939] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 08/11/2020] [Accepted: 08/19/2020] [Indexed: 12/16/2022] Open
Abstract
We report on a potential strategy involving the exogenous neurotrophic factors (NTF) for enhancing the neurotrophic capacity of human adipose stem cells (ASC) in vitro. For this, ASC were stimulated for three days using NTF, i.e., nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin 3 (NT3), NT4, glial cell-derived neurotrophic factor (GDNF), and ciliary neurotrophic factor (CNTF). The resulting conditioned medium (CM) as well as individual NTF exhibited distinct effects on axonal outgrowth from dorsal root ganglion (DRG) explants. In particular, CM derived from NT3-stimulated ASC (CM-NT3-ASC) promoted robust axonal outgrowth. Subsequent transcriptional analysis of DRG cultures in response to CM-NT3-ASC displayed significant upregulation of STAT-3 and GAP-43. In addition, phosphoproteomic analysis of NT3-stimulated ASC revealed significant changes in the phosphorylation state of different proteins that are involved in cytokine release, growth factors signaling, stem cell maintenance, and differentiation. Furthermore, DRG cultures treated with CM-NT3-ASC exhibited significant changes in the phosphorylation levels of proteins involved in tubulin and actin cytoskeletal pathways, which are crucial for axonal growth and elongation. Thus, the results obtained at the transcriptional, proteomic, and cellular level reveal significant changes in the neurotrophic capacity of ASC following NT3 stimulation and provide new options for improving the axonal growth-promoting potential of ASC in vitro.
Collapse
Affiliation(s)
- Katharina M. Prautsch
- Department of Plastic, Reconstructive, Aesthetic and Hand Surgery, University Hospital Basel, Spitalstrasse 21, 4021 Basel, Switzerland; (K.M.P.); (D.J.S.); (D.F.K.)
- Department of Pathology, University Hospital Basel, Hebelstrasse 20, 4021 Basel, Switzerland;
- Department of Biomedical Engineering, University of Basel, Gewerbestrasse 14, 4123 Allschwil, Switzerland
| | - Alexander Schmidt
- Biozentrum, University of Basel, Klingelbergstrasse 50/70, 4056 Basel, Switzerland;
| | - Viola Paradiso
- Department of Pathology, University Hospital Basel, Hebelstrasse 20, 4021 Basel, Switzerland;
| | - Dirk J. Schaefer
- Department of Plastic, Reconstructive, Aesthetic and Hand Surgery, University Hospital Basel, Spitalstrasse 21, 4021 Basel, Switzerland; (K.M.P.); (D.J.S.); (D.F.K.)
- Department of Biomedicine, University Hospital Basel, Hebelstrasse 20, 4021 Basel, Switzerland;
| | - Raphael Guzman
- Department of Biomedicine, University Hospital Basel, Hebelstrasse 20, 4021 Basel, Switzerland;
- Department of Neurosurgery, University Hospital Basel, Spitalstrasse 21, 4021 Basel, Switzerland
| | - Daniel F. Kalbermatten
- Department of Plastic, Reconstructive, Aesthetic and Hand Surgery, University Hospital Basel, Spitalstrasse 21, 4021 Basel, Switzerland; (K.M.P.); (D.J.S.); (D.F.K.)
- Department of Pathology, University Hospital Basel, Hebelstrasse 20, 4021 Basel, Switzerland;
- Department of Biomedical Engineering, University of Basel, Gewerbestrasse 14, 4123 Allschwil, Switzerland
| | - Srinivas Madduri
- Department of Plastic, Reconstructive, Aesthetic and Hand Surgery, University Hospital Basel, Spitalstrasse 21, 4021 Basel, Switzerland; (K.M.P.); (D.J.S.); (D.F.K.)
- Department of Pathology, University Hospital Basel, Hebelstrasse 20, 4021 Basel, Switzerland;
- Department of Biomedical Engineering, University of Basel, Gewerbestrasse 14, 4123 Allschwil, Switzerland
- Department of Biomedicine, University Hospital Basel, Hebelstrasse 20, 4021 Basel, Switzerland;
| |
Collapse
|
8
|
Yang S, Wang C, Zhu J, Lu C, Li H, Chen F, Lu J, Zhang Z, Yan X, Zhao H, Sun X, Zhao L, Liang J, Wang Y, Peng J, Wang X. Self-assembling peptide hydrogels functionalized with LN- and BDNF- mimicking epitopes synergistically enhance peripheral nerve regeneration. Theranostics 2020; 10:8227-8249. [PMID: 32724468 PMCID: PMC7381722 DOI: 10.7150/thno.44276] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Accepted: 05/31/2020] [Indexed: 12/16/2022] Open
Abstract
The regenerative capacity of the peripheral nervous system is closely related to the role that Schwann cells (SCs) play in construction of the basement membrane containing multiple extracellular matrix proteins and secretion of neurotrophic factors, including laminin (LN) and brain-derived neurotrophic factor (BDNF). Here, we developed a self-assembling peptide (SAP) nanofiber hydrogel based on self-assembling backbone Ac-(RADA)4-NH2 (RAD) dual-functionalized with laminin-derived motif IKVAV (IKV) and a BDNF-mimetic peptide epitope RGIDKRHWNSQ (RGI) for peripheral nerve regeneration, with the hydrogel providing a three-dimensional (3D) microenvironment for SCs and neurites. Methods: Circular dichroism (CD), atomic force microscopy (AFM), and scanning electron microscopy (SEM) were used to characterize the secondary structures, microscopic structures, and morphologies of self-assembling nanofiber hydrogels. Then the SC adhesion, myelination and neurotrophin secretion were evaluated on the hydrogels. Finally, the SAP hydrogels were injected into hollow chitosan tubes to bridge a 10-mm-long sciatic nerve defect in rats, and in vivo gene expression at 1 week, axonal regeneration, target muscular re-innervation, and functional recovery at 12 weeks were assessed. Results: The bioactive peptide motifs were covalently linked to the C-terminal of the self-assembling peptide and the functionalized peptides could form well-defined nanofibrous hydrogels capable of providing a 3D microenvironment similar to native extracellular matrix. SCs displayed improved cell adhesion on hydrogels with both IKV and RGI, accompanied by increased cell spreading and elongation relative to other groups. RSCs cultured on hydrogels with IKV and RGI showed enhanced gene expression of NGF, BDNF, CNTF, PMP22 and NRP2, and decreased gene expression of NCAM compared with those cultured on other three groups after a 7-day incubation. Additionally, the secretion of NGF, BDNF, and CNTF of RSCs was significantly improved on dual-functionalized peptide hydrogels after 3 days. At 1 week after implantation, the expressions of neurotrophin and myelin-related genes in the nerve grafts in SAP and Autograft groups were higher than that in Hollow group, and the expression of S100 in groups containing both IKV and RGI was significantly higher than that in groups containing either IKV or RGI hydrogels, suggesting enhanced SC proliferation. The morphometric parameters of the regenerated nerves, their electrophysiological performance, the innervated muscle weight and remodeling of muscle fibers, and motor function showed that RAD/IKV/RGI and RAD/IKV-GG-RGI hydrogels could markedly improve axonal regeneration with enhanced re-myelination and motor functional recovery through the synergetic effect of IKV and RGI functional motifs. Conclusions: We found that the dual-functionalized SAP hydrogels promoted RSC adhesion, myelination, and neurotrophin secretion in vitro and successfully bridged a 10-mm gap representing a sciatic nerve defect in rats in vivo. The results demonstrated the synergistic effect of IKVAV and RGI on axonal regrowth and function recovery after peripheral nerve injury.
Collapse
Affiliation(s)
- Shuhui Yang
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| | - Chong Wang
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing 100853, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province 226007, China
| | - Jinjin Zhu
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang, Hangzhou 310016, China
| | - Changfeng Lu
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing 100853, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province 226007, China
- Department of Orthopaedics and Trauma, Peking University People's Hospital, Beijing 100191, China
| | - Haitao Li
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing 100853, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province 226007, China
| | - Fuyu Chen
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing 100853, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province 226007, China
| | - Jiaju Lu
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| | - Zhe Zhang
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| | - Xiaoqing Yan
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
- School of Clinical Medicine, Tsinghua University, Beijing 100084, China
| | - He Zhao
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| | - Xiaodan Sun
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| | - Lingyun Zhao
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| | - Jing Liang
- Department of Pediatrics, Tianjin Hospital, Tianjin University, No. 406 Jiefang Nan Road, Tianjin 300211, China
| | - Yu Wang
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing 100853, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province 226007, China
| | - Jiang Peng
- Institute of Orthopedics, Chinese PLA General Hospital, Beijing 100853, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province 226007, China
| | - Xiumei Wang
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
| |
Collapse
|
9
|
Functionalized nerve conduits for peripheral nerve regeneration: A literature review. HAND SURGERY & REHABILITATION 2020; 39:343-351. [PMID: 32485240 DOI: 10.1016/j.hansur.2020.05.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 05/21/2020] [Accepted: 05/26/2020] [Indexed: 12/17/2022]
Abstract
Functionalized neurotube are a third-generation of conduits with chemical or architectural bioactivity developed for axonal proliferation. The goal of this review is to provide a synopsis of the functionalized nerve conduits described in the literature according to their chemical and architectural properties and answer two questions: what are their mechanisms of action? Has their efficacy been proven compared to the autologous nerve graft? Our literature review relates all kind of conduits corresponding to functionalized neurotubes in peripheral nerve regeneration found in Medline and PubMed Central. Studies developing nerve gaps, chemotactic or structural features promoting each conduit, results, efficiency were selected. Fifty-five studies were selected and classified in: (a) intraluminal neurotrophic factors; (b) cell-based therapy (combined-in-vein muscles, amniotic membrane, Schwann cells, stem cells); (c) extracellular matrix proteins; (d) tissue engineering; (e) bioimplants. Functionalized neurotubes showed significantly better functional results than after end-to-end nerve suture. No studies can be able to show that neurotube results were better than autologous nerve graft results. We included all studies regardless of effectives to evaluate quality of reinnervation with modern tubulization. Functionalized neurotubes promote basic conduits for peripheral nerve regeneration. Thanks to bioengineering and microsurgery improvement, further neurotubes could promote best level of regeneration and functional recovery to successfully bridge a critical nerve gap.
Collapse
|
10
|
Reactivation of Denervated Schwann Cells by Embryonic Spinal Cord Neurons to Promote Axon Regeneration and Remyelination. Stem Cells Int 2019; 2019:7378594. [PMID: 31885623 PMCID: PMC6915008 DOI: 10.1155/2019/7378594] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Accepted: 09/06/2019] [Indexed: 01/04/2023] Open
Abstract
In peripheral nerve injuries (PNIs) in which proximal axons do not regenerate quickly enough, significant chronic degeneration of Schwann cells (SCs) can occur at the distal stump of the injured nerve and obstruct regeneration. Cell transplantation can delay the degeneration of SCs, but transplanted cells fail to generate voluntary electrical impulses without downstream signal stimulation from the central nervous system. In this study, we combined cell transplantation and nerve transfer strategies to investigate whether the transplantation of embryonic spinal cord cells could benefit the microenvironment of the distal stump of the injured nerve. The experiment consisted of two stages. In the first-stage surgery, common peroneal nerves were transected, and embryonic day 14 (E14) cells or cell culture medium was transplanted into the distal stump of the CPs. Six months after the first-stage surgery, the transplanted cells were removed, and the nerve segment distal to the transplanted site was used to bridge freshly cut tibial nerves to detect whether the cell-treated graft promoted axon growth. The phenotypic changes and the neurotrophic factor expression pattern of SCs distal to the transplanted site were detected at several time points after cell transplantation and excision. The results showed that at different times after transplantation, the cells could survive and generate neurons. Thus, the neurons play the role of proximal axons to prevent chronic degeneration and fibrosis of SCs. After excision of the transplanted cells, the SCs returned to their dedifferentiated phenotype and upregulated growth-associated gene expression. The ability of SCs to be activated again allowed a favorable microenvironment to be created and enhanced the regeneration and remyelination of proximal axons. Muscle reinnervation was also elevated. This transplantation strategy could provide a treatment option for complex neurological injuries in the clinic.
Collapse
|