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    18 June 2015, Volume 10 Issue 6 Previous Issue    Next Issue
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    Inhibition of kinesin-5 improves regeneration of injured axons by a novel microtubule-based mechanism
    Peter W. Baas, Andrew J. Matamoros
    2015, 10 (6):  845-849.  doi: 10.4103/1673-5374.158351
    Abstract ( 286 )   PDF (764KB) ( 899 )   Save

    Microtubules have been identified as a powerful target for augmenting regeneration of injured adult axons in the central nervous system. Drugs that stabilize microtubules have shown some promise, but there are concerns that abnormally stabilizing microtubules may have only limited benefits for regeneration, while at the same time may be detrimental to the normal work that microtubules perform for the axon. Kinesin-5 (also called kif11 or Eg5), a molecular motor protein best known for its crucial role in mitosis, acts as a brake on microtubule movements by other motor proteins in the axon. Drugs that inhibit kinesin-5, originally developed to treat cancer, result in greater mobility of microtubules in the axon and an overall shift in the forces on the microtubule array. As a result, the axon grows faster, retracts less, and more readily enters environments that are inhibitory to axonal regeneration. Thus, drugs that inhibit kinesin-5 offer a novel microtubule-based means to boost axonal regeneration without the concerns that accompany abnormal stabilization of the microtubule array. Even so, inhibiting kinesin-5 is not without its own caveats, such as potential problems with navigation of the regenerating axon to its target, as well as morphological effects on dendrites that could affect learning and memory if the drugs reach the brain.

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    Mesenchymal stem cells-based therapy as a potential treatment in neurodegenerative disorders: is the escape from senescence an answer?
    Alessandro Castorina, Marta Anna Szychlinska,Rubina Marzagalli, Giuseppe Musumeci
    2015, 10 (6):  850-858.  doi: 10.4103/1673-5374.158352
    Abstract ( 244 )   PDF (1324KB) ( 1015 )   Save

    Aging is the most prominent risk factor contributing to the development of neurodegenerative disorders. In the United States, over 35 million of elderly people suffer from age-related diseases. Aging impairs the self-repair ability of neuronal cells, which undergo progressive deterioration.Once initiated, this process hampers the already limited regenerative power of the central nervous system, making the search for new therapeutic strategies particularly difficult in elderly affected patients. So far, mesenchymal stem cells have proven to be a viable option to ameliorate certain aspects of neurodegeneration, as they possess high proliferative rate and differentiate in vitro into multiple lineages. However, accumulating data have demonstrated that during long-term culture, mesenchymal stem cells undergo spontaneous transformation. Transformed mesenchymal stem cells show typical features of senescence, including the progressive shortening of telomers, which results in cell loss and, as a consequence, hampered regenerative potential. These evidences, in line with those observed in mesenchymal stem cells isolated from old donors, suggest that senescence may represent a limit to mesenchymal stem cells exploitation in therapy, prompting scholars to either find alternative sources of pluripotent cells or to arrest the age-related transformation. In the present review, we summarize findings from recent literature, and critically discuss some of the major hurdles encountered in the search of appropriate sources of mesenchymal stem cells, as well as benefits arising from their use in neurodegenerative diseases. Finally, we provide some insights that may aid in the development of strategies to arrest or, at least, delay the aging of mesenchymal stem cells to improve their therapeutic potential.

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    Strategies to avoid a missed diagnosis of co-occurring concussion in post-acute patients having a spinal cord injury
    David S. Kushner
    2015, 10 (6):  859-861.  doi: 10.4103/1673-5374.158329
    Abstract ( 262 )   PDF (179KB) ( 643 )   Save

    Research scientists and clinicians should be aware that missed diagnoses of mild-moderate traumatic brain injuries in post-acute patients having spinal cord injuries may approach 60–74% with certain risk factors, potentially causing clinical consequences for patients, and confounding the results of clinical research studies. Factors leading to a missed diagnosis may include acute trauma-related life-threatening issues, sedation/intubation, subtle neuropathology on neuroimaging, failure to collect Glasgow Coma Scale scores or duration of posttraumatic amnesia, or lack of validity of this information, and overlap in neuro-cognitive symptoms with emotional responses to spinal cord injuries. Strategies for avoiding a missed diagnosis of mild-moderate traumatic brain injuries in patients having a spinal cord injuries are highlighted in this perspective.

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    Phage display: development of nanocarriers for targeted drug delivery to the brain
    Babak Bakhshinejad, Marzieh Karimi, Mohammad Khalaj-Kondori
    2015, 10 (6):  862-865.  doi: 10.4103/1673-5374.158330
    Abstract ( 245 )   PDF (533KB) ( 907 )   Save

    The blood brain barrier represents a formidable obstacle for the transport of most systematically administered neurodiagnostics and neurotherapeutics to the brain. Phage display is a high throughput screening strategy that can be used for the construction of nanomaterial peptide libraries. These libraries can be screened for finding brain targeting peptide ligands. Surface functionalization of a variety of nanocarriers with these brain homing peptides is a sophisticated way to develop nanobiotechnology-based drug delivery platforms that are able to cross the blood brain barrier. These efficient drug delivery systems raise our hopes for the diagnosis and treatment of various brain disorders in the future.

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    Matrilin-2, an extracellular adaptor protein, is needed for the regeneration of muscle, nerve and other tissues
    Éva Korpos, Ferenc Deák, Ibolya Kiss
    2015, 10 (6):  866-869.  doi: 10.4103/1673-5374.158332
    Abstract ( 314 )   PDF (1172KB) ( 1263 )   Save

    The extracellular matrix (ECM) performs essential functions in the differentiation, maintenance and remodeling of tissues during development and regeneration, and it undergoes dynamic changes during remodeling concomitant to alterations in the cell-ECM interactions. Here we discuss recent data addressing the critical role of the widely expressed ECM protein, matrilin-2 (Matn2) in the timely onset of differentiation and regeneration processes in myogenic, neural and other tissues and in tumorigenesis. As a multiadhesion adaptor protein, it interacts with other ECM proteins and integrins. Matn2 promotes neurite outgrowth, Schwann cell migration, neuromuscular junction formation, skeletal muscle and liver regeneration and skin wound healing. Matn2 deposition by myoblasts is crucial for the timely induction of the global switch toward terminal myogenic differentiation during muscle regeneration by affecting transforming growth factor beta/bone morphogenetic protein 7/Smad and other signal transduction pathways. Depending on the type of tissue and the pathomechanism, Matn2 can also promote or suppress tumor growth.

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    Protein deacetylases and axonal regeneration
    Fanny Ng, Bor Luen Tang
    2015, 10 (6):  870-871.  doi: 10.4103/1673-5374.158333
    Abstract ( 169 )   PDF (275KB) ( 730 )   Save
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    Neuroprotective properties of kavalactones
    Yew-Min Tzeng, Meng-Jen Lee
    2015, 10 (6):  875-877.  doi: 10.4103/1673-5374.158335
    Abstract ( 217 )   PDF (426KB) ( 1123 )   Save
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    Mercury-induced neurotoxicity and neuroprotective effects of berberine
    Ahmed E. Abdel Moneim
    2015, 10 (6):  881-882.  doi: 10.4103/1673-5374.158336
    Abstract ( 237 )   PDF (365KB) ( 816 )   Save
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    Receptor-mediated increase in rabies virus axonal transport
    Shani Gluska, Stefan Finke, Eran Perlson
    2015, 10 (6):  883-884.  doi: 10.4103/1673-5374.158337
    Abstract ( 239 )   PDF (288KB) ( 1420 )   Save
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    The kallikrein-kinin system: a promising therapeutic target for traumatic brain injury
    Sarah Hopp, Christiane Albert-Weissenberger
    2015, 10 (6):  885-886.  doi: 10.4103/1673-5374.158339
    Abstract ( 230 )   PDF (142KB) ( 696 )   Save
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    Fine-tuning of cortical progenitor proliferation by thalamic afferents
    Katrin Gerstmann, Geraldine Zimmer
    2015, 10 (6):  887-888.  doi: 10.4103/1673-5374.158341
    Abstract ( 205 )   PDF (340KB) ( 869 )   Save
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    Blood-brain barrier modeling: challenges and perspectives
    Tobias Ruck, Stefan Bittner, Sven G. Meuth
    2015, 10 (6):  889-891.  doi: 10.4103/1673-5374.158342
    Abstract ( 228 )   PDF (498KB) ( 782 )   Save
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    Modification of autophagy-lysosomal pathway as a neuroprotective treatment for spinal cord injury
    Marta M. Lipinski, Junfang Wu
    2015, 10 (6):  892-893.  doi: 10.4103/1673-5374.158344
    Abstract ( 345 )   PDF (359KB) ( 668 )   Save
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    Laser capture microdissection: from its principle to applications in research on neurodegeneration
    Sook Hyun Chung, Weiyong Shen
    2015, 10 (6):  897-898.  doi: 10.4103/1673-5374.158346
    Abstract ( 305 )   PDF (351KB) ( 1059 )   Save
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    Onecut transcription factors in retinal development and maintenance
    Darshan Sapkota, Xiuqian Mu
    2015, 10 (6):  899-900.  doi: 10.4103/1673-5374.158350
    Abstract ( 366 )   PDF (403KB) ( 627 )   Save

    视网膜是视觉系统的一个基本组成部分。大多数眼疾的特点是视网膜变性,大部分是由遗传或环境因素引起的。这就强调了研究能够调节哺乳动物视网膜神经元产生和维持遗传分子机制的重要性。

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    Is retinoic acid a signal for nerve regeneration in insects?
    Katrin Bui-Göbbels, Renata Medinaceli Quintela, Peter Bräunig, Jörg Mey
    2015, 10 (6):  901-903.  doi: 10.4103/1673-5374.158349
    Abstract ( 248 )   PDF (637KB) ( 965 )   Save
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    12 hours after cerebral ischemia is the optimal time for bone marrow mesenchymal stem cell transplantation
    Seyed Mojtaba Hosseini, Mohammad Farahmandnia, Zahra Razi, Somayeh Delavarifar, Benafsheh Shakibajahromi
    2015, 10 (6):  904-908.  doi: 10.4103/1673-5374.158354
    Abstract ( 310 )   PDF (756KB) ( 712 )   Save

    Cell therapy using stem cell transplantation against cerebral ischemia has been reported. However, it remains controversial regarding the optimal time for cell transplantation and the transplantation route. Rat models of cerebral ischemia were established by occlusion of the middle cerebral artery. At 1, 12 hours, 1, 3, 5 and 7 days after cerebral ischemia, bone marrow mesenchymal stem cells were injected via the tail vein. At 28 days after cerebral ischemia, rat neurological function was evaluated using a 6-point grading scale and the pathological change of ischemic cerebral tissue was observed by hematoxylin-eosin staining. Under the fluorescence microscope, the migration of bone marrow mesenchymal stem cells was examined by PKH labeling. Caspase-3 activity was measured using spectrophotometry. The optimal neurological function recovery, lowest degree of ischemic cerebral damage, greatest number of bone marrow mesenchymal stem cells migrating to peri-ischemic area, and lowest caspase-3 activity in the ischemic cerebral tissue were observed in rats that underwent bone marrow mesenchymal stem cell transplantation at 12 hours after cerebral ischemia. These findings suggest that 12 hours after cerebral ischemia is the optimal time for tail vein injection of bone marrow mesenchymal stem cell transplantation against cerebral ischemia, and the strongest neuroprotective effect of this cell therapy appears at this time.

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    In vivo tracking of human adipose-derived stem cells labeled with ferumoxytol in rats with middle cerebral artery occlusion by magnetic resonance imaging
    Yan Yin, Xiang Zhou, Xin Guan, Yang Liu, Chang-bin Jiang, Jing Liu4
    2015, 10 (6):  909-915.  doi: 10.4103/1673-5374.158355
    Abstract ( 399 )   PDF (1068KB) ( 889 )   Save

    Ferumoxytol, an iron replacement product, is a new type of superparamagnetic iron oxide approved by the US Food and Drug Administration. Herein, we assessed the feasibility of tracking transplanted human adipose-derived stem cells labeled with ferumoxytol in middle cerebral artery occlusion-injured rats by 3.0 T MRI in vivo. 1 × 104 human adipose-derived stem cells labeled with ferumoxytol-heparin-protamine were transplanted into the brains of rats with middle cerebral artery occlusion. Neurologic impairment was scored at 1, 7, 14, and 28 days after transplantation. T2-weighted imaging and enhanced susceptibility-weighted angiography were used to observe transplanted cells. Results of imaging tests were compared with results of Prussian blue staining. The modified neurologic impairment scores were significantly lower in rats transplanted with cells at all time points except 1 day post-transplantation compared with rats without transplantation. Regions with hypointense signals on T2-weighted and enhanced susceptibility-weighted angiography images corresponded with areas stained by Prussian blue, suggesting the presence of superparamagnetic iron oxide particles within the engrafted cells. Enhanced susceptibility-weighted angiography image exhibited better sensitivity and contrast in tracing ferumoxytol-heparin-protamine-labeled human adipose-derived stem cells compared with T2-weighted imaging in routine MRI.

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    Low-frequency transcranial magnetic stimulation is beneficial for enhancing synaptic plasticity in the aging brain
    Zhan-chi Zhang, Feng Luan, Chun-yan Xie, Dan-dan Geng, Yan-yong Wang, Jun Ma
    2015, 10 (6):  916-924.  doi: 10.4103/1673-5374.158356
    Abstract ( 342 )   PDF (1312KB) ( 913 )   Save

    In the aging brain, cognitive function gradually declines and causes a progressive reduction in the structural and functional plasticity of the hippocampus. Transcranial magnetic stimulation is an emerging and novel neurological and psychiatric tool used to investigate the neurobiology of cognitive function. Recent studies have demonstrated that low-frequency transcranial magnetic stimulation (≤1 Hz) ameliorates synaptic plasticity and spatial cognitive deficits in learning-impaired mice. However, the mechanisms by which this treatment improves these deficits during normal aging are still unknown. Therefore, the current study investigated the effects of transcranial magnetic stimulation on the brain-derived neurotrophic factor signal pathway, synaptic protein markers, and spatial memory behavior in the hippocampus of normal aged mice. The study also investigated the downstream regulator, Fyn kinase, and the downstream effectors, synaptophysin and growth-associated protein 43 (both synaptic markers), to determine the possible mechanisms by which transcranial magnetic stimulation regulates cognitive capacity. Transcranial magnetic stimulation with low intensity (110% average resting motor threshold intensity, 1 Hz) increased mRNA and protein levels of brain-derived neurotrophic factor, tropomyosin receptor kinase B, and Fyn in the hippocampus of aged mice. The treatment also upregulated the mRNA and protein expression of synaptophysin and growth-associated protein 43 in the hippocampus of these mice. In conclusion, brain-derived neurotrophic factor signaling may play an important role in sustaining and regulating structural synaptic plasticity induced by transcranial magnetic stimulation in the hippocampus of aging mice, and Fyn may be critical during this regulation. These responses may change the structural plasticity of the aging hippocampus, thereby improving cognitive function.

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    Curcumin improves synaptic plasticity impairment induced by HIV-1gp120 V3 loop
    Ling-ling Shen, Ming-liang Jiang, Si-si Liu, Min-chun Cai, Zhong-qiu Hong, Li-qing Lin, Yan-yan Xing, Gui-lin Chen, Rui Pan, Li-juan Yang, Ying Xu, Jun Dong
    2015, 10 (6):  925-931.  doi: 10.4103/1673-5374.158358
    Abstract ( 308 )   PDF (985KB) ( 723 )   Save

    Curcumin has been shown to significantly improve spatial memory impairment induced by HIV-1 gp120 V3 in rats, but the electrophysiological mechanism remains unknown. Using extracellular microelectrode recording techniques, this study confirmed that the gp120 V3 loop could suppress long-term potentiation in the rat hippocampal CA1 region and synaptic plasticity, and that curcumin could antagonize these inhibitory effects. Using a Fura-2/AM calcium ion probe, we found that curcumin resisted the effects of the gp120 V3 loop on hippocampal synaptosomes and decreased Ca2+ concentration in synaptosomes. This effect of curcumin was identical to nimodipine, suggesting that curcumin improved the inhibitory effects of gp120 on synaptic plasticity, ameliorated damage caused to the central nervous system, and might be a potential neuroprotective drug.

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    Hydrogen sulfide intervention in focal cerebral ischemia/reperfusion injury in rats
    Xin-juan Li, Chao-kun Li, Lin-yu Wei, Na Lu, Guo-hong Wang, Hong-gang Zhao, Dong-liang Li
    2015, 10 (6):  932-937.  doi: 10.4103/1673-5374.158353
    Abstract ( 251 )   PDF (1151KB) ( 913 )   Save

    The present study aimed to explore the mechanism underlying the protective effects of hydrogen sulfide against neuronal damage caused by cerebral ischemia/reperfusion. We established the middle cerebral artery occlusion model in rats via the suture method. Ten minutes after middle cerebral artery occlusion, the animals were intraperitoneally injected with hydrogen sulfide donor compound sodium hydrosulfide. Immunofluorescence revealed that the immunoreactivity of P2X7 in the cerebral cortex and hippocampal CA1 region in rats with cerebral ischemia/reperfusion injury decreased with hydrogen sulfide treatment. Furthermore, treatment of these rats with hydrogen sulfide significantly lowered mortality, the Longa neurological deficit scores, and infarct volume. These results indicate that hydrogen sulfide may be protective in rats with local cerebral ischemia/reperfusion injury by down-regulating the expression of P2X7 receptors.

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    Acrylamide neurotoxicity on the cerebrum of weaning rats
    Su-min Tian, Yu-xin Ma, Jing Shi, Ting-ye Lou, Shuai-shuai Liu, Guo-ying Li
    2015, 10 (6):  938-943.  doi: 10.4103/1673-5374.158357
    Abstract ( 316 )   PDF (1453KB) ( 871 )   Save

    The mechanism underlying acrylamide-induced neurotoxicity remains controversial. Previous studies have focused on acrylamide-induced toxicity in adult rodents, but neurotoxicity in weaning rats has not been investigated. To explore the neurotoxic effect of acrylamide on the developing brain, weaning rats were gavaged with 0, 5, 15, and 30 mg/kg acrylamide for 4 consecutive weeks. No obvious neurotoxicity was observed in weaning rats in the low-dose acrylamide group (5 mg/kg). However, rats from the moderate- and high-dose acrylamide groups (15 and 30 mg/kg) had an abnormal gait. Furthermore, biochemical tests in these rats demonstrated that glutamate concentration was significantly reduced, and γ-aminobutyric acid content was significantly increased and was dependent on acrylamide dose. Immunohistochemical staining showed that in the cerebral cortex, γ-aminobutyric acid, glutamic acid decarboxylase and glial fibrillary acidic protein expression increased remarkably in the moderate- and high-dose acrylamide groups. These results indicate that in weaning rats, acrylamide is positively associated with neurotoxicity in a dose-dependent manner, which may correlate with upregulation of γ-aminobutyric acid and subsequent neuronal degeneration after the initial acrylamide exposure.

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    Delayed hippocampal neuronal death in young gerbil following transient global cerebral ischemia is related to higher and longer-term expression of p63 in the ischemic hippocampus
    Eun Joo Bae, Bai Hui Chen, Bing Chun Yan, Bich Na Shin, Jeong Hwi Cho, In Hye Kim, Ji Hyeon Ahn, Jae Chul Lee, Hyun-Jin Tae, Seongkweon Hong, Dong Won Kim, Jun Hwi Cho, Yun Lyul Lee, Moo-Ho Won, Joon Ha Park
    2015, 10 (6):  944-950.  doi: 10.4103/1673-5374.158359
    Abstract ( 215 )   PDF (1647KB) ( 781 )   Save

    The tumor suppressor p63 is one of p53 family members and plays a vital role as a regulator of neuronal apoptosis in the development of the nervous system. However, the role of p63 in mature neuronal death has not been addressed yet. In this study, we first compared ischemia-induced effects on p63 expression in the hippocampal regions (CA1–3) between the young and adult gerbils subjected to 5 minutes of transient global cerebral ischemia. Neuronal death in the hippocampal CA1 region of young gerbils was significantly slow compared with that in the adult gerbils after transient global cerebral ischemia. p63 immunoreactivity in the hippocampal CA1 pyramidal neurons in the sham-operated young group was significantly low compared with that in the sham-operated adult group. p63 immunoreactivity was apparently changed in ischemic hippocampal CA1 pyramidal neurons in both ischemia-operated young and adult groups. In the ischemia-operated adult groups, p63 immunoreactivity in the hippocampal CA1 pyramidal neurons was significantly decreased at 4 days post-ischemia; however, p63 immunoreactivity in the ischemia-operated young group was significantly higher than that in the ischemia-operated adult group. At 7 days post-ischemia, p63 immunoreactivity was decreased in the hippocampal CA1 pyramidal neurons in both ischemia-operated young and adult groups. Change patterns of p63 level in the hippocampal CA1 region of adult and young gerbils after ischemic damage were similar to those observed in the immunohistochemical results. These findings indicate that higher and longer-term expression of p63 in the hippocampal CA1 region of the young gerbils after ischemia/reperfusion may be related to more delayed neuronal death compared to that in the adults.

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    Neuroprotective effect of rapamycin on spinal cord injury via activation of the Wnt/β-catenin signaling pathway
    Kai Gao, Yan-song Wang, Ya-jiang Yuan, Zhang-hui Wan, Tian-chen Yao, Hai-hong Li, Pei-fu Tang, Xi-fan Mei
    2015, 10 (6):  951-957.  doi: 10.4103/1673-5374.158360
    Abstract ( 481 )   PDF (1137KB) ( 908 )   Save

    The Wnt/β-catenin signaling pathway plays a crucial role in neural development, axonal guidance, neuropathic pain remission and neuronal survival. In this study, we initially examined the effect of rapamycin on the Wnt/β-catenin signaling pathway after spinal cord injury, by intraperitoneally injecting spinal cord injured rats with rapamycin over 2 days. Western blot analysis and immunofluorescence staining were used to detect the expression levels of β-catenin protein, ca-spase-3 protein and brain-derived neurotrophic factor protein, components of the Wnt/β-catenin signaling pathway. Rapamycin increased the levels of β-catenin and brain-derived neurotrophic factor in the injured spinal cord, improved the pathological morphology at the injury site, reduced the loss of motor neurons, and promoted motor functional recovery in rats after spinal cord injury. Our experimental findings suggest that the neuroprotective effect of rapamycin intervention is mediated through activation of the Wnt/β-catenin signaling pathway after spinal cord injury.

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    Hydrogen-rich saline injection into the subarachnoid cavity within 2 weeks promotes recovery after acute spinal cord injury
    Jian-long Wang, Qing-shan Zhang, Kai-di Zhu, Jian-feng Sun, Ze-peng Zhang, Jian-wen Sun, Ke-xiang Zhang
    2015, 10 (6):  958-964.  doi: 10.4103/1673-5374.158361
    Abstract ( 170 )   PDF (4215KB) ( 1003 )   Save

    Hydrogen can relieve tissue-damaging oxidative stress, inflammation and apoptosis. Injection of hydrogen-rich saline is an effective method for transporting molecular hydrogen. We hypothesized that hydrogen-rich saline would promote the repair of spinal cord injury induced by Allen’s method in rats. At 0.5, 1, 2, 4, 8, 12 and 24 hours after injury, then once daily for 2 weeks, 0.25 mL/kg hydrogen-rich saline was infused into the subarachnoid space through a catheter. Results at 24 hours, 48 hours, 1 week and 2 weeks after injury showed that hydrogen-rich saline markedly reduced cell death, inflammatory cell infiltration, serum malondialdehyde content, and caspase-3 immunoreactivity, elevated serum superoxide dismutase activity and calcitonin gene-related peptide immunoreactivity, and improved motor function in the hindlimb. The present study confirms that hydrogen-rich saline injected within 2 weeks of injury effectively contributes to the repair of spinal cord injury in the acute stage.

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    Biological conduits combining bone marrow mesenchymal stem cells and extracellular matrix to treat long-segment sciatic nerve defects
    Yang Wang, Zheng-wei Li, Min Luo, Ya-jun Li, Ke-qiang Zhang
    2015, 10 (6):  965-971.  doi: 10.4103/1673-5374.158362
    Abstract ( 171 )   PDF (873KB) ( 957 )   Save

    The transplantation of polylactic glycolic acid conduits combining bone marrow mesenchymal stem cells and extracellular matrix gel for the repair of sciatic nerve injury is effective in some respects, but few data comparing the biomechanical factors related to the sciatic nerve are available. In the present study, rabbit models of 10-mm sciatic nerve defects were prepared. The rabbit models were repaired with autologous nerve, a polylactic glycolic acid conduit + bone marrow mesenchymal stem cells, or a polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel. After 24 weeks, mechanical testing was performed to determine the stress relaxation and creep parameters. Following sciatic nerve injury, the magnitudes of the stress decrease and strain increase at 7,200 seconds were largest in the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel group, followed by the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells group, and then the autologous nerve group. Hematoxylin-eosin staining demonstrated that compared with the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells group and the autologous nerve group, a more complete sciatic nerve regeneration was found, including good myelination, regularly arranged nerve fibers, and a completely degraded and resorbed conduit, in the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel group. These results indicate that bridging 10-mm sciatic nerve defects with a polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel construct increases the stress relaxation under a constant strain, reducing anastomotic tension. Large elongations under a constant physiological load can limit the anastomotic opening and shift, which is beneficial for the regeneration and functional reconstruction of sciatic nerve. Better regeneration was found with the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel grafts than with the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells grafts and the autologous nerve grafts.

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    Sialic acid accelerates the electrophoretic velocity of injured dorsal root ganglion neurons
    Chen-xu Li, Guo-ying Ma, Min-fang Guo, Ying Liu
    2015, 10 (6):  972-975.  doi: 10.4103/1673-5374.158364
    Abstract ( 165 )   PDF (294KB) ( 754 )   Save

    Peripheral nerve injury has been shown to result in ectopic spontaneous discharges on soma and injured sites of sensory neurons, thereby inducing neuropathic pain. With the increase of membrane proteins on soma and injured site neurons, the negatively charged sialic acids bind to the external domains of membrane proteins, resulting in an increase of this charge. We therefore speculate that the electrophoretic velocity of injured neurons may be faster than non-injured neurons. The present study established rat models of neuropathic pain via chronic constriction injury. Results of the cell electrophoresis test revealed that the electrophoretic velocity of injured neuronal cells was faster than that of non-injured (control) cells. We then treated cells with divalent cations of Ca2+ and organic compounds with positive charges, polylysine to counteract the negatively charged sialic acids, or neuraminidase to specifically remove sialic acids from the membrane surface of injured neurons. All three treatments significantly reduced the electrophoretic velocity of injured neuronal cells. These findings suggest that enhanced sialic acids on injured neurons may accelerate the electrophoretic velocity of injured neurons.

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    N-Propionylmannosamine stimulates axonal elongation in a murine model of sciatic nerve injury
    Christian Witzel, Werner Reutter, G. Björn Stark, Georgios Koulaxouzidis
    2015, 10 (6):  976-981.  doi: 10.4103/1673-5374.150744
    Abstract ( 309 )   PDF (947KB) ( 633 )   Save

    Increasing evidence indicates that sialic acid plays an important role during nerve regeneration. Sialic acids can be modified in vitro as well as in vivo using metabolic oligosaccharide engineering of the N-acyl side chain. N-Propionylmannosamine (ManNProp) increases neurite outgrowth and accelerates the reestablishment of functional synapses in vitro. We investigated the influence of systemic ManNProp application using a specific in vivo mouse model. Using mice expressing axonal fluorescent proteins, we quantified the extension of regenerating axons, the number of regenerating axons, the number of arborising axons and the number of branches per axon 5 days after injury. Sciatic nerves from non-expressing mice were grafted into those expressing yellow fluorescent protein. We began a twice-daily intraperitoneal application of either peracetylated ManNProp (200 mg/kg) or saline solution 5 days before injury, and continued it until nerve harvest (5 days after transection). ManNProp significantly increased the mean distance of axonal regeneration (2.49 mm vs. 1.53 mm; P < 0.005) and the number of arborizing axons (21% vs. 16%; P = 0.008) 5 days after sciatic nerve grafting. ManNProp did not affect the number of regenerating axons or the number of branches per arborizing axon. The biochemical glycoengineering of the N-acyl side chain of sialic acid might be a promising approach for improving peripheral nerve regeneration.

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    Stem Cell Ophthalmology Treatment Study (SCOTS) for retinal and optic nerve diseases: a preliminary report
    Jeffrey N. Weiss, Steven Levy, Alexis Malkin
    2015, 10 (6):  982-988.  doi: 10.4103/1673-5374.158365
    Abstract ( 397 )   PDF (4781KB) ( 1686 )   Save

    In this report, we present the results of a single patient with optic neuropathy treated within the Stem Cell Ophthalmology Treatment Study (SCOTS). SCOTS is an Institutional Review Board approved clinical trial and is the largest ophthalmology stem cell study registered at the National Institutes of Health to date- www.clinicaltrials.gov Identifier NCT 01920867. SCOTS utilizes autologous bone marrow-derived stem cells in the treatment of optic nerve and retinal diseases. Pre- and post-treatment comprehensive eye exams were independently performed at the Wilmer Eye Institute at the Johns Hopkins Hospital, USA. A 27 year old female patient had lost vision approximately 5 years prior to enrollment in SCOTS. Pre-treatment best-corrected visual acuity at the Wilmer Eye Institute was 20/800 Right Eye (OD) and 20/4,000 Left Eye (OS). Four months following treatment in SCOTS, the central visual acuity had improved to 20/100 OD and 20/40 OS.

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    Shrinkage of ipsilateral taste buds and hyperplasia of contralateral taste buds following chorda tympani nerve transection
    Yi-ke Li, Juan-mei Yang, Yi-bo Huang, Dong-dong Ren, Fang-lu Chi
    2015, 10 (6):  989-995.  doi: 10.4103/1673-5374.158366
    Abstract ( 297 )   PDF (1618KB) ( 1003 )   Save

    The morphological changes that occur in the taste buds after denervation are not well understood in rats, especially in the contralateral tongue epithelium. In this study, we investigated the time course of morphological changes in the taste buds following unilateral nerve transection. The role of the trigeminal component of the lingual nerve in maintaining the structural integrity of the taste buds was also examined. Twenty-four Sprague-Dawley rats were randomly divided into three groups: control, unilateral chorda tympani nerve transection and unilateral chorda tympani nerve transection + lingual nerve transection. Rats were allowed up to 42 days of recovery before being euthanized. The taste buds were visualized using a cytokeratin 8 antibody. Taste bud counts, volumes and taste receptor cell numbers were quantified and compared among groups. No significant difference was detected between the chorda tympani nerve transection and chorda tympani nerve transection + lingual nerve transection groups. Taste bud counts, volumes and taste receptor cell numbers on the ipsilateral side all decreased significantly compared with control. On the contralateral side, the number of taste buds remained unchanged over time, but they were larger, and taste receptor cells were more numerous postoperatively. There was no evidence for a role of the trigeminal branch of the lingual nerve in maintaining the structural integrity of the anterior taste buds.

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    Peripheral nerve repair: a hot spot analysis on treatment methods from 2010 to 2014
    Guang-yao Liu, Yan Jin, Qiao Zhang, Rui Li
    2015, 10 (6):  996-1002.  doi: 10.4103/1673-5374.158368
    Abstract ( 215 )   PDF (455KB) ( 658 )   Save

    Therapeutic strategies for neurological deficits and for promoting nerve regeneration after peripheral nerve injuries have received much focus in clinical research. Advances in basic research in recent years have increased our understanding of the anatomy of peripheral nerves and the importance of the microenvironment. Various new intervention methods have been developed, but with varying effectiveness. In the present study, we selected 911 papers on different repair methods for peripheral nerve injury from the Web of Science and indexed in the Science Citation Index from 2010 to 2014. We quantitatively examine new repair methods and strategies using bibliometrics, and we discuss the present state of knowledge and the problems and prospects of various repair methods, including nerve transfer, neural transplantation, tissue engineering and genetic engineering. Our findings should help in the study and development of repair methods for peripheral nerve injury.

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    Nerve autografts and tissue-engineered materials for the repair of peripheral nerve injuries: a 5-year bibliometric analysis
    Yuan Gao,Yu-ling Wang, Dan Kong, Bo Qu, Xiao-jing Su, Huan Li, Hong-ying Pi
    2015, 10 (6):  1003-1008.  doi: 10.4103/1673-5374.158369
    Abstract ( 429 )   PDF (470KB) ( 892 )   Save

    With advances in biomedical methods, tissue-engineered materials have developed rapidly as an alternative to nerve autografts for the repair of peripheral nerve injuries. However, the materials selected for use in the repair of peripheral nerve injuries, in particular multiple injuries and large-gap defects, must be chosen carefully. Various methods and materials for protecting the healthy tissue and repairing peripheral nerve injuries have been described, and each method or material has advantages and disadvantages. Recently, a large amount of research has been focused on tissue-engineered materials for the repair of peripheral nerve injuries. Using the keywords “peripheral nerve injury”, “autotransplant”, “nerve graft”, and “biomaterial”, we retrieved publications using tissue-engineered materials for the repair of peripheral nerve injuries appearing in the Web of Science from 2010 to 2014. The country with the most total publications was the USA. The institutions that were the most productive in this field include Hannover Medical School (Germany), Washington University (USA), and Nantong University (China). The total number of publications using tissue-engineered materials for the repair of peripheral nerve injuries gradually increased over time, as did the number of Chinese publications, suggesting that China has made many scientific contributions to this field of research.

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