Loading...

Table of Content

    15 December 2017, Volume 12 Issue 12 Previous Issue    Next Issue
    For Selected: Toggle Thumbnails
    Non-invasive brain stimulation to promote motor and functional recovery following spinal cord injury
    Aysegul Gunduz, John Rothwell, Joan Vidal, Hatice Kumru
    2017, 12 (12):  1933-1938.  doi: 10.4103/1673-5374.221143
    Abstract ( 171 )   PDF (211KB) ( 347 )   Save

    We conducted a systematic review of studies using non-invasive brain stimulation (NIBS: repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS)) as a research and clinical tool aimed at improving motor and functional recovery or spasticity in patients following spinal cord injury (SCI) under the assumption that if the residual corticospinal circuits could be stimulated appropriately, the changes might be accompanied by functional recovery or an improvement in spasticity. This review summarizes the literature on the changes induced by NIBS in the motor and functional recovery and spasticity control of the upper and lower extremities following SCI.

    Related Articles | Metrics
    The contribution of oligodendrocytes and oligodendrocyte progenitor cells to central nervous system repair in multiple sclerosis: perspectives for remyelination therapeutic strategies
    Adriana Octaviana Dulamea
    2017, 12 (12):  1939-1944.  doi: 10.4103/1673-5374.221146
    Abstract ( 140 )   PDF (306KB) ( 378 )   Save

      Oligodencrocytes (OLs) are the main glial cells of the central nervous system involved in myelination of axons. In multiple sclerosis (MS), there is an imbalance between demyelination and remyelination processes, the last one performed by oligodendrocyte progenitor cells (OPCs) and OLs, resulting into a permanent demyelination, axonal damage and neuronal loss. In MS lesions, astrocytes and microglias play an important part in permeabilization of blood-brain barrier and initiation of OPCs proliferation. Migration and differentiation of OPCs are influenced by various factors and the process is finalized by insufficient acummulation of OLs into the MS lesion. In relation to all these processes, the author will discuss the potential targets for remyelination strategies

    Related Articles | Metrics
    MicroRNAs in Parkinson’s disease and emerging therapeutic targets
    Bridget Martinez, Philip V. Peplow
    2017, 12 (12):  1945-1959.  doi: 10.4103/1673-5374.221147
    Abstract ( 161 )   PDF (764KB) ( 368 )   Save
    Parkinson’s disease (PD) is the second most common age-related neurodegenerative disorder, with the clinical main symptoms caused by a loss of dopaminergic neurons in the substantia nigra, corpus striatum and brain cortex. Over 90% of patients with PD have sporadic PD and occur in people with no known family history of the disorder. Currently there is no cure for PD. Treatment with medications to increase dopamine relieves the symptoms but does not slow down or reverse the damage to neurons in the brain. Increasing evidence points to inflammation as a chief mediator of PD with inflammatory response mechanisms, involving microglia and leukocytes, activated following loss of dopaminergic neurons. Oxidative stress is also recognized as one of the main causes of PD, and excessive reactive oxygen species (ROS) and reactive nitrogen species can lead to dopaminergic neuron vulnerability and eventual death. MicroRNAs control a range of physiological and pathological functions, and may serve as potential targets for intervention against PD to mitigate damage to the brain. Several studies have demonstrated that microRNAs can regulate oxidative stress and prevent ROS-mediated damage to dopaminergic neurons, suggesting that specific microRNAs may be putative targets for novel therapeutic strategies in PD. Recent human and animal studies have identified a large number of dysregulated microRNAs in PD brain tissue samples, many of which were downregulated. The dysregulated microRNAs affect downstream targets such as SNCA, PARK2, LRRK2, TNFSF13B, LTA, SLC5A3, PSMB2, GSR, GBA, LAMP-2A, HSC. Apart from one study, none of the studies reviewed had used agomirs or antagomirs to reverse the levels of downregulated or upregulated microRNAs, respectively, in mouse models of PD or with isolated human or mouse dopaminergic cells. Further large-scale studies of brain tissue samples collected with short postmortem interval from human PD patients are warranted to provide more information on the microRNA profiles in different brain regions and to test for gender differences.
    Related Articles | Metrics
    Surgical reconstruction of spinal cord circuit provides functional return in humans
    Thomas Carlstedt, Nicholas James, Mårten Risling
    2017, 12 (12):  1960-1963.  doi: 10.4103/1673-5374.221145
    Abstract ( 123 )   PDF (365KB) ( 337 )   Save

    This mini review describes the current surgical strategy for restoring function after traumatic spinal nerve root avulsion in brachial or lumbosacral plexus injury in man. As this lesion is a spinal cord or central nervous injury functional return depends on spinal cord nerve cell growth within the central nervous system. Basic science, clinical research and human application has demonstrated good and useful motor function after ventral root avulsion followed by spinal cord reimplantation. Recently, sensory return could be demonstrated following spinal cord surgery bypassing the injured primary sensory neuron. Experimental data showed that most of the recovery depended on new growth reinnervating peripheral receptors Restored sensory function and the return of spinal reflex was demonstrated by electrophysiology and functional magnetic resonance imaging of human cortex. This spinal cord surgery is a unique treatment of central nervous system injury resulting in useful functional return. Further improvements will not depend on surgical improvements. Adjuvant therapy aiming at ameliorating the activity in retinoic acid elements in dorsal root ganglion neurons could be a new therapeutic avenue in restoring spinal cord circuits after nerve root avulsion injury.

    Related Articles | Metrics
    Environmental cues determine the fate of astrocytes after spinal cord injury
    Fatima M. Nathan, Shuxin Li
    2017, 12 (12):  1964-1970.  doi: 10.4103/1673-5374.221144
    Abstract ( 180 )   PDF (399KB) ( 313 )   Save
    Reactive astrogliosis occurs after central nervous system (CNS) injuries whereby resident astrocytes form rapid responses along a graded continuum. Following CNS lesions, naive astrocytes are converted into reactive astrocytes and eventually into scar-forming astrocytes that block axon regeneration and neural repair. It has been known for decades that scarring development and its related extracellular matrix molecules interfere with regeneration of injured axons after CNS injury, but the cellular and molecular mechanisms for controlling astrocytic scar formation and maintenance are not well known. Recent use of various genetic tools has made tremendous progress in better understanding genesis of reactive astrogliosis. Especially, the latest experiments demonstrate environment-dependent plasticity of reactive astrogliosis because reactive astrocytes isolated from injured spinal cord form scarring astrocytes when transplanted into injured spinal cord, but revert in retrograde to naive astrocytes when transplanted into naive spinal cord. The interactions between upregulated type I collagen and its receptor integrin β1 and the N-cadherin-mediated cell adhesion appear to play major roles for local astrogliosis around the lesion. This review centers on the environment-dependent plasticity of reactive astrogliosis after spinal cord injury and its potential as a therapeutic target.
    Related Articles | Metrics
    Formin’ bridges between microtubules and actin filaments in axonal growth cones
    István Földi, Szilárd Szikora, József Mihály
    2017, 12 (12):  1971-1973.  doi: 10.4103/1673-5374.221148
    Abstract ( 163 )   PDF (733KB) ( 396 )   Save
    Related Articles | Metrics
    Conductive polymer scaffolds to improve neural recovery
    Shang Song, Paul M. George
    2017, 12 (12):  1976-1978.  doi: 10.4103/1673-5374.221151
    Abstract ( 134 )   PDF (252KB) ( 334 )   Save
    Related Articles | Metrics
    Coenzyme Q10 as a therapeutic candidate for treating inherited photoreceptor degeneration
    Xun Zhang, Lincoln Biswas1, Ali Mohammad Tohari, James Reilly, Luca Tiano, Xinhua Shu
    2017, 12 (12):  1979-1981.  doi: 10.4103/1673-5374.221152
    Abstract ( 120 )   PDF (565KB) ( 325 )   Save
    Related Articles | Metrics
    Implications of periostin in the development of subarachnoid hemorrhage-induced brain injuries
    Hirofumi Nishikawa, Hidenori Suzuki
    2017, 12 (12):  1982-1984.  doi: 10.4103/1673-5374.221150
    Abstract ( 125 )   PDF (249KB) ( 306 )   Save
    Related Articles | Metrics
    The Drosophila adult neuromuscular junction as a model for unravelling amyloid peptide influence on synapse dynamics
    Begoña López-Arias, Ignacio Monedero, Enrique Turiégano, Laura Torroja
    2017, 12 (12):  1987-1989.  doi: 10.4103/1673-5374.221154
    Abstract ( 138 )   PDF (867KB) ( 367 )   Save
    Related Articles | Metrics
    Bone marrow-derived mesenchymal stem cells ameliorate sodium nitrite-induced hypoxic brain injury in a rat model
    Elham H.A. Ali, Omar A. Ahmed-Farid, Amany A. E. Osman
    2017, 12 (12):  1990-1999.  doi: 10.4103/1673-5374.221155
    Abstract ( 172 )   PDF (951KB) ( 883 )   Save

    Sodium nitrite (NaNO2) is an inorganic salt used broadly in chemical industry. NaNO2 is highly reactive with hemoglobin causing hypoxia. Mesenchymal stem cells (MSCs) are capable of differentiating into a variety of tissue specific cells and MSC therapy is a potential method for improving brain functions. This work aims to investigate the possible therapeutic role of bone marrow-derived MSCs against NaNO2 induced hypoxic brain injury. Rats were divided into control group (treated for 3 or 6 weeks), hypoxic (HP) group (subcutaneous injection of 35 mg/kg NaNO2 for 3 weeks to induce hypoxic brain injury), HP recovery groups N-2wR and N-3wR (treated with the same dose of NaNO2 for 2 and 3 weeks respectively,followed by 4-week or 3-week self-recovery respectively), and MSCs treated groups N-2wSC and N-3wSC (treated with the same dose of NaNO2 for 2 and 3 weeks respectively, followed by one injection of 2 × 106 MSCs via the tail vein in combination with 4 week self-recovery or intravenous injection of NaNO2 for 1 week in combination with 3 week self-recovery). The levels of neurotransmitters (norepinephrine,dopamine, serotonin), energy substances (adenosine monophosphate, adenosine diphosphate, adenosine triphosphate), and oxidative stress markers (malondialdehyde, nitric oxide, 8-hydroxy-2′-eoxyguanosine,glutathione reduced form, and oxidized glutathione) in the frontal cortex and midbrain were measured using high performance liquid chromatography. At the same time, hematoxylin-eosin staining was performed to observe the pathological change of the injured brain tissue. Compared with HP group, pathological change of brain tissue was milder, the levels of malondialdehyde, nitric oxide, oxidized glutathione, 8-hydroxy-2′-deoxyguanosine, norepinephrine, serotonin, glutathione reduced form, and adenosine triphosphate in the frontal cortex and midbrain were significantly decreased, and glutathione reduced form/oxidized glutathione and adenosine onophosphate/adenosine triphosphate ratio were significantly increased in the MSCs treated groups. These findings suggest that bone marrow-derived MSCs exhibit neuroprotective effects against NaNO2-induced hypoxic brain injury through exerting anti-oxidative effects and providing energy to the brain.

    Related Articles | Metrics
    Electroacupuncture improves neurovascular unit reconstruction by promoting collateral circulation and angiogenesis
    Lei Shi, Hong-mei Cao, Ying Li, Shi-xin Xu, Yan Zhang, Yang Zhang, Zhe-feng Jin
    2017, 12 (12):  2000-2006.  doi: 10.4103/1673-5374.221156
    Abstract ( 138 )   PDF (1113KB) ( 314 )   Save

    Acupuncture at Shuigou (GV26) shows good clinical efficacy for treating stroke, but its mechanism remains poorly understood. In this study, a cerebral infarction model of ischemia/reperfusion injury received electroacupuncture at GV26 (15 Hz and 1 mA, continuous wave [biphasic pulses], for 5 minutes). Electroacupuncture effectively promoted regional cerebral blood flow on the infarct and non-infarct sides, increased infarct lesions, lectin, and number of blood vessels, upregulated von Willebrand factor and cell proliferation marker Ki67 expression, and diminished neurological severity score. These findings confirm that electroacupuncture at GV26 promotes establishment of collateral circulation and angiogenesis, and improves neurological function.

    Related Articles | Metrics
    Neuronal injury and tumor necrosis factor-alpha immunoreactivity in the rat hippocampus in the early period of asphyxia-induced cardiac arrest under normothermia
    Hyun-Jin Tae, Il Jun Kang, Tae-Kyeong Lee, Jeong Hwi Cho, Jae-Chul Lee, Myoung Cheol Shin, Yoon Sung Kim, Jun Hwi Cho,Jong-Dai Kim, Ji Hyeon Ahn, Joon Ha Park, In-Shik Kim, Hyang-Ah Lee, Yang Hee Kim, Moo-Ho Won, Young Joo Lee
    2017, 12 (12):  2007-2013.  doi: 10.4103/1673-5374.221157
    Abstract ( 140 )   PDF (9372KB) ( 277 )   Save

    Low survival rate occurs in patients who initially experience a spontaneous return of circulation after cardiac arrest (CA). In this study, we induced asphyxial CA in adult male Sprague-Daley rats, maintained their body temperature at 37 ± 0.5°C, and then observed the survival rate during the post-resuscitation phase. We examined neuronal damage in the hippocampus using cresyl violet (CV) and Fluore-Jade B (F-J B) staining, and pro-inflammatory response using ionized calcium-binding adapter molecule 1 (Iba-1), glial fibrillary acidic protein (GFAP), and tumor necrosis factor-alpha (TNF-α) immunohistochemistry in the hippocampus after asphyxial CA in rats under normothermia. Our results show that the survival rate decreased gradually post-CA (about 63% at 6 hours, 37% at 1 day, and 8% at 2 days post-CA). Rats were sacrificed at these points in time post-CA, and no neuronal damage was found in the hippocampus until 1 day post-CA. However, some neurons in the stratum pyramidale of the CA region in the hippocampus were dead 2 days post-CA. Iba-1 immunoreactive microglia in the CA1 region did not change until 1 day post-CA, and they were activated (enlarged cell bodies with short and thicken processes) in all layers 2 days post-CA. Meanwhile, GFAP-immunoreactive astrocytes did not change significantly until 2 days post-CA. TNF-αimmunoreactivity decreased significantly in neurons of the stratum pyramidale in the CA1 region 6 hours post-CA, decreased gradually until 1 day post-CA, and increased significantly again 2 days post-CA. These findings suggest that low survival rate of normothermic rats in the early period of asphyxia-induced CA is related to increased TNF-α immunoreactivity, but not to neuronal damage in the hippocampal CA1 region.

    Related Articles | Metrics
    D-dimer may predict poor outcomes in patients with aneurysmal subarachnoid hemorrhage: a retrospective study
    Jun-hui Liu, Xiang-kui Li, Zhi-biao Chen, Qiang Cai, Long Wang, Ying-hu Ye, Qian-xue Chen
    2017, 12 (12):  2014-2020.  doi: 10.4103/1673-5374.221158
    Abstract ( 119 )   PDF (305KB) ( 695 )   Save

    Serum biomarkers may play a reliable role in predicting the outcomes of patients with aneurysmal subarachnoid hemorrhage. This study retrospectively analyzed the relationship between serum biomarkers on admission and outcomes in patients with aneurysmal subarachnoid hemorrhage. We recruited 146 patients with aneurysmal subarachnoid hemorrhage who were treated in Renmin Hospital of Wuhan University of China between 1 May 2014 and 30 March 2016. There were 57 males and 89 females included and average age of included patients was 57.03 years old. Serum samples were taken immediately on admission (within 48 hours after initial hemorrhage) and the levels of serum biomarkers were detected. Baseline information, complications, and outcomes at 6 months were recorded. Univariate and multivariate logistic regression analyses were used to explore the relationship between biomarkers and clinical outcomes. Receiver operating characteristic curves were obtained to investigate the possibility of the biomarkers predicting prognosis. Of the 146 patients, 102 patients achieved good outcomes and 44 patients had poor outcomes. Univariate and multivariate analyses showed that high World Federation of Neurosurgical Societies grade, high serum D-dimer levels, and high neurological complications were significantly associated with poor outcomes. Receiver operating characteristic curves verified that D-dimer levels were associated with poor outcomes. D-dimer levels strongly correlated with neurological complications. In conclusion, we suggest that D-dimer levels are a good independent prognostic factor for poor outcomes in patients with aneurysmal subarachnoid hemorrhage.

    Related Articles | Metrics
    Central post-stroke pain due to injury of the spinothalamic tract in patients with cerebral infarction: a diffusion tensor tractography imaging study
    Sung Ho Jang, Jun Lee, Sang Seok Yeo
    2017, 12 (12):  2021-2024.  doi: 10.4103/1673-5374.221159
    Abstract ( 139 )   PDF (470KB) ( 288 )   Save

    Many studies using diffusion tensor tractography (DTT) have demonstrated that injury of the spinothalamic tract (STT) is the pathogenetic mechanism of central post-stroke pain (CPSP) in intracerebral hemorrhage; however, there is no DTT study reporting the pathogenetic mechanism of CPSP in cerebral infarction.In this study, we investigated injury of the STT in patients with CPSP following cerebral infarction,using DTT. Five patients with CPSP following cerebral infarction and eight age- and sex-matched healthy control subjects were recruited for this study. STT was examined using DTT. Among DTT parameters of the affected STT, fractional anisotropy and tract volume were decreased by more than two standard deviations in two patients (patients 1 and 2) and three patients (patients 3, 4, and 5), respectively, compared with those of the control subjects, while mean diffusivity value was increased by more than two standard deviations in one patient (patient 2). Regarding DTT configuration, all affected STTs passed through adjacent part of the infarct and three STTs showed narrowing. These findings suggest that injury of the STT might be a pathogenetic etiology of CPSP in patients with cerebral infarction.

    Related Articles | Metrics
    Mitochondrial protective and anti-apoptotic effects of Rhodiola crenulata extract on hippocampal neurons in a rat model of Alzheimer’s disease
    Jun-mei Wang, Ze-qiang Qu, Jin-lang Wu, Peter Chung, Yuan-shan Zeng
    2017, 12 (12):  2025-2034.  doi: 10.4103/1673-5374.221160
    Abstract ( 147 )   PDF (1367KB) ( 412 )   Save

    In our previous study, we found that the edible alcohol extract of the root of the medicinal plant Rhodiola crenulata (RCE) improved spatial cognition in a rat model of Alzheimer’s disease. Another study from our laboratory showed that RCE enhanced neural cell proliferation in the dentate gyrus of the hippocampus and prevented damage to hippocampal neurons in a rat model of chronic stress-induced depression.However, the mechanisms underlying the neuroprotective effects of RCE are unclear. In the present study, we investigated the anti-apoptotic effect of RCE and its neuroprotective mechanism of action in a rat model of Alzheimer’s disease established by intracerebroventricular injection of streptozotocin. The rats were pre-administered RCE at doses of 1.5, 3.0 or 6.0 g/kg for 21 days before model establishment.ATP and cytochrome c oxidase levels were significantly decreased in rats with Alzheimer’s disease. Furthermore, neuronal injury was obvious in the hippocampus, with the presence of a large number of apoptotic neurons. In comparison, in rats given RCE pretreatment, ATP and cytochrome c oxidase levels were markedly increased, the number of apoptotic neurons was reduced, and mitochondrial injury was mitigated. The 3.0 g/kg dose of RCE had the optimal effect. These findings suggest that pretreatment with RCE prevents mitochondrial dysfunction and protects hippocampal neurons from apoptosis in rats with Alzheimer’s disease.

    Related Articles | Metrics
    Neural computational modeling reveals a major role of corticospinal gating of central oscillations in the generation of essential tremor
    Hong-en Qu, Chuanxin M. Niu, Si Li, Man-zhao Hao, Zi-xiang Hu, Qing Xie, Ning Lan
    2017, 12 (12):  2035-2044.  doi: 10.4103/1673-5374.221161
    Abstract ( 121 )   PDF (1739KB) ( 345 )   Save

    Essential tremor, also referred to as familial tremor, is an autosomal dominant genetic disease and the most common movement disorder.It typically involves a postural and motor tremor of the hands, head or other part of the body. Essential tremor is driven by a central oscillation signal in the brain. However, the corticospinal mechanisms involved in the generation of essential tremor are unclear. Therefore, in this study, we used a neural computational model that includes both monosynaptic and multisynaptic corticospinal pathways interacting with a propriospinal neuronal network. A virtual arm model is driven by the central oscillation signal to simulate tremor activity behavior.Cortical descending commands are classified as alpha or gamma through monosynaptic or multisynaptic corticospinal pathways, which converge respectively on alpha or gamma motoneurons in the spinal cord. Several scenarios are evaluated based on the central oscillation signal passing down to the spinal motoneurons via each descending pathway. The simulated behaviors are compared with clinical essential tremor characteristics to identify the corticospinal pathways responsible for transmitting the central oscillation signal. A propriospinal neuron with strong cortical inhibition performs a gating function in the generation of essential tremor. Our results indicate that the propriospinal neuronal network is essential for relaying the central oscillation signal and the production of essential tremor.

    Related Articles | Metrics
     Magnetic resonance imaging-guided focused ultrasound to increase localized blood spinal cord barrier permeability
    Allison H. Payne, Gregory W. Hawryluk, Yoshimi Anzai, Henrik Odéen, Megan A. Ostlie, Ethan C. Reichert, Amanda J. Stump,Satoshi Minoshima, Donna J. Cross
    2017, 12 (12):  2045-2049.  doi: 10.4103/1673-5374.221162
    Abstract ( 151 )   PDF (980KB) ( 291 )   Save

    Spinal cord injury (SCI) affects thousands of people every year in the USA, and most patients are left with some permanent paralysis. Therapeutic options are limited and only modestly affect outcome. To address this issue, we used magnetic resonance imaging-guided focused ultrasound (MRgFUS) as a non-invasive approach to increase permeability in the blood spinal cord barrier (BSCB). We hypothesize that localized, controlled sonoporation of the BSCB by MRgFUS will aid delivery of therapeutics to the injury. Here, we report our preliminary findings for the ability of MRgFUS to increase BSCB permeability in the thoracic spinal cord of a normal rat model. First, an excised portion of normal rat spinal column was used to characterize the acoustic field and to estimate the insertion losses that could be expected in an MRgFUS blood spinal cord barrier opening. Then, in normal rats, MRgFUS was applied in combination with intravenously administered microbubbles to the spinal cord region. Permeability of the BSCB was indicated as signal enhancement by contrast administered prior to T1-weighted magnetic resonance imaging and verified by Evans blue dye. Neurological testing using the Basso, Beattie, and Breshnahan scale and the ladder walk was normal in 8 of 10 rats tested. Two rats showed minor impairment indicating need for further refinement of parameters. No gross tissue damage was evident by histology. In this study, we have opened successfully the blood spinal cord barrier in the thoracic region of the normal rat spine using magnetic resonance-guided focused ultrasound combined with microbubbles.

    Related Articles | Metrics
    Does vitamin C have the ability to augment the therapeutic effect of bone marrow-derived mesenchymal stem cells on spinal cord injury?
    Nesrine Salem, Mohamed Y. Salem, Mohammed M. Elmaghrabi, Moataz A. Elawady, Mona A. Elawady, Dina Sabry,Ashraf Shamaa, Abdel-Haleem H. Elkasapy, Noha Ibrhim, Azza Elamir
    2017, 12 (12):  2050-2058.  doi: 10.4103/1673-5374.221163
    Abstract ( 164 )   PDF (3163KB) ( 336 )   Save

    Methylprednisolone (MP) is currently the only drug confirmed to exhibit a neuroprotective effect on acute spinal cord injury (SCI). Vitamin C (VC) is a natural water-soluble antioxidant that exerts neuroprotective effects through eliminating free radical damage to nerve cells. Bone marrow mesenchymal stem cells (BMMSCs), as multipotent stem cells, are promising candidates in SCI repair. To evaluate the therapeutic effects of MP, VC and BMMSCs on traumatic SCI, 80 adult male rats were randomly divided into seven groups: control, SCI (SCI induction by weight-drop method), MP (SCI induction, followed by administration of 30 mg/kg MP via the tail vein, once every other 6 hours, for five times), VC (SCI induction, followed by intraperitoneal administration of 100 mg/kg VC once a day, for 28 days), MP + VC (SCI induction, followed by administration of MP and VC as the former), BMMSCs (SCI induction, followed by injection of 3×106 BMMSCs at the injury site), and BMMSCs + VC (SCI induction, followed by BMMSCs injection and VC administration as the former). Locomotor recovery was assessed using the Basso Mouse Scale. Injured spinal cord tissue was evaluated using hematoxylin-eosin staining and immunohistochemical staining. Expression of transforming growth factor-beta, tumor necrosis factor-alpha, and matrix metalloproteinase-2 genes was determined using real-time quantitative PCR. BMMSCs intervention better promoted recovery of nerve function of rats with SCI, mitigated nerve cell damage, and decreased expression of transforming growth factor-beta, tumor necrosis factor-alpha, and matrix metalloproteinase-2 genes than MP and/or VC. More importantly, BMMSCs in combination with VC induced more obvious improvements. These results suggest that VC can enhance the neuroprotective effects of BMMSCs against SCI.

    Related Articles | Metrics
    Non-concomitant cortical structural and functional alterations in sensorimotor areas following incomplete spinal cord injury
    Yu Pan, Wei-bei Dou, Yue-heng Wang, Hui-wen Luo, Yun-xiang Ge, Shu-yu Yan, Quan Xu, Yuan-yuan Tu, Yan-qing Xiao,Qiong Wu, Zhuo-zhao Zheng, Hong-liang Zhao
    2017, 12 (12):  2059-2066.  doi: 10.4103/1673-5374.221165
    Abstract ( 179 )   PDF (575KB) ( 361 )   Save

    Brain plasticity, including anatomical changes and functional reorganization, is the physiological basis of functional recovery after spinal cord injury (SCI). The correlation between brain anatomical changes and functional reorganization after SCI is unclear. This study aimed to explore whether alterations of cortical structure and network function are concomitant in sensorimotor areas after incomplete SCI.Eighteen patients with incomplete SCI (mean age 40.94 ± 14.10 years old; male:female, 7:11) and 18 healthy subjects (37.33 ± 11.79 years old; male:female, 7:11) were studied by resting state functional magnetic resonance imaging. Gray matter volume (GMV) and functional connectivity were used to evaluate cortical structure and network function, respectively. There was no significant alteration of GMV in sensorimotor areas in patients with incomplete SCI compared with healthy subjects. Intra-hemispheric functional connectivity between left primary somatosensory cortex (BA1) and left primary motor cortex (BA4), and left BA1 and left somatosensory association cortex (BA5) was decreased, as well as inter-hemispheric functional connectivity between left BA1 and right BA4, left BA1 and right BA5, and left BA4 and right BA5 in patients with SCI. Functional connectivity between both BA4 areas was also decreased. The decreased functional connectivity between the left BA1 and the right BA4 positively correlated with American Spinal Injury Association sensory score in SCI patients. The results indicate that alterations of cortical anatomical structure and network functional connectivity in sensorimotor areas were non-concomitant in patients with incomplete SCI, indicating the network functional changes in sensorimotor areas may not be dependent on anatomic structure. The strength of functional connectivity within sensorimotor areas could serve as a potential imaging biomarker for assessment and prediction of sensory function in patients with incomplete SCI. This trial was registered with the Chinese Clinical Trial Registry (registration number: ChiCTR-ROC-17013566).

    Related Articles | Metrics
    Diffusion tensor imaging of spinal microstructure in healthy adults: improved resolution with the readout segmentation of long variable echo-trains
    Bu-tian Zhang, Meng Li, Li-li Yu, Yi-meng Dai, Shao-nan Yu, Jin-lan Jiang
    2017, 12 (12):  2067-2070.  doi: 10.4103/1673-5374.221166
    Abstract ( 138 )   PDF (401KB) ( 318 )   Save

    Diffusion tensor imaging plays an important role in the accurate diagnosis and prognosis of spinal cord diseases. However, because of technical limitations, the imaging sequences used in this technique cannot reveal the fine structure of the spinal cord with precision. We used the readout segmentation of long variable echo-trains (RESOLVE) sequence in this cross-sectional study of 45 healthy volunteers aged 20 to 63 years. We found that the RESOLVE sequence significantly increased the resolution of the diffusion images and improved the median signal-to-noise ratio of the middle (C4–6) and lower (C7–T1) cervical segments to the level of the upper cervical segment. In addition, the values of fractional anisotropy and radial diffusivity were significantly higher in white matter than in gray matter. Our study verified that the RESOLVE sequence could improve resolution of diffusion tensor imaging in clinical applications and provide accurate baseline data for the diagnosis and treatment of cervical spinal cord diseases.

    Related Articles | Metrics
    Topiramate as a neuroprotective agent in a rat model of spinal cord injury
    Firat Narin, Sahin Hanalioglu, Huseyin Ustun, Kamer Kilinc, Burcak Bilginer
    2017, 12 (12):  2071-2076.  doi: 10.4103/1673-5374.221164
    Abstract ( 185 )   PDF (456KB) ( 308 )   Save

    Topiramate (TPM) is a widely used antiepileptic and antimigraine agent which has been shown to exert
    neuroprotective effects in various experimental traumatic brain injury and stroke models. However, its utility in spinal cord injury has not been studied extensively. Thus, we evaluated effects of TPM on secondary cellular injury mechanisms in an experimental rat model of traumatic spinal cord injury (SCI). After rat models of thoracic contusive SCI were established by free weight-drop method, TPM (40 mg/kg) was given at 12-hour intervals for four times orally. Post TPM treatment, malondialdehyde and protein carbonyl levels were significantly reduced and reduced glutathione levels were increased, while immunoreactivity for endothelial nitric oxide synthase, inducible nitric oxide synthase, and apoptotic peptidase activating factor 1 was diminished in SCI rats. In addition, TPM treatment improved the functional recovery of SCI rats.This study suggests that administration of TPM exerts neuroprotective effects on SCI.

    Related Articles | Metrics
    Autologous transplantation with fewer fibers repairs large peripheral nerve defects
    Jiu-xu Deng, Dian-yin Zhang, Ming Li, Jian Weng, Yu-hui Kou, Pei-xun Zhang, Na Han, Bo Chen, Xiao-feng Yin, Bao-guo Jiang
    2017, 12 (12):  2077-2083.  doi: 10.4103/1673-5374.221167
    Abstract ( 119 )   PDF (1459KB) ( 333 )   Save

    Peripheral nerve injury is a serious disease and its repair is challenging. A cable-style autologous graft is the gold standard for repairing long peripheral nerve defects; however, ensuring that the minimum number of transplanted nerve attains maximum therapeutic effect remains poorly understood. In this study, a rat model of common peroneal nerve defect was established by resecting a 10-mm long right common peroneal nerve. Rats receiving transplantation of the common peroneal nerve in situ were designated as the in situ graft group. Ipsilateral sural nerves (10–30 mm long) were resected to establish the one sural nerve graft group, two sural nerves cable-style nerve graft group and three sural nerves cable-style nerve graft group. Each bundle of the peroneal nerve was 10 mm long. To reduce the barrier effect due to invasion by surrounding tissue and connective-tissue overgrowth between neural stumps, small gap sleeve suture was used in both proximal and distal terminals to allow repair of the injured common peroneal nerve. At three months postoperatively, recovery of nerve function and morphology was observed using osmium tetroxide staining and functional detection. The results showed that the number of regenerated nerve fibers, common peroneal nerve function index, motor nerve conduction velocity, recovery of myodynamia, and wet weight ratios of tibialis anterior muscle were not significantly different among the one sural nerve graft group, two sural nerves cable-style nerve graft group, and three sural nerves cable-style nerve graft group. These data suggest that the repair effect achieved using one sural nerve graft with a lower number of nerve fibers is the same as that achieved using the two sural nerves cable-style nerve graft and three sural nerves cable-style nerve graft. This indicates that according to the ‘multiple amplification’ phenomenon, one small nerve graft can provide a good therapeutic effect for a large peripheral nerve defect.

    Related Articles | Metrics
    Long non-coding RNA NONMMUG014387 promotes Schwann cell proliferation after peripheral nerve injury,
    Bin Pan, Zhong-ju Shi, Jia-yin Yan, Jia-he Li, Shi-qing Feng
    2017, 12 (12):  2084-2091.  doi: 10.4103/1673-5374.221168
    Abstract ( 157 )   PDF (1678KB) ( 282 )   Save

    Schwann cells play a critical role in peripheral nerve regeneration through dedifferentiation and proliferation. In a previous study, we performed microarray analysis of the sciatic nerve after injury. Accordingly, we predicted that long non-coding RNA NONMMUG014387 may promote Schwann cell proliferation after peripheral nerve injury, as bioinformatic analysis revealed that the target gene of NONMMUG014387 was collagen triple helix repeat containing 1 (Cthrc1). Cthrc1 may promote cell proliferation in a variety of cells by activating Wnt/PCP signaling. Nonetheless, bioinformatic analysis still needs to be verified by biological experiment. In this study, the candidate long non-coding RNA, NONMMUG014387, was overexpressed in mouse Schwann cells by recombinant adenovirus transfection. Plasmid pHBAd-MCMV-GFP-NONMMUG014387 and pHBAd-MCMV-GFP were transfected into Schwann cells. Schwann cells were divided into three groups: control (Schwann cells without intervention), Ad-GFP (Schwann cells with GFP overexpression), and Ad-NONMMUGO148387 (Schwann cells with GFP and NONMMUGO148387 overexpression). Cell Counting Kit-8 assay was used to evaluate proliferative capability of mouse Schwann cells after NONMMUG014387 overexpression. Polymerase chain reaction and western blot assay were performed to investigate target genes and downstream pathways of NONMMUG014387. Cell proliferation was significantly increased in Schwann cells overexpressing lncRNA NONMMUG014387 compared with the other two groups. Further, compared with the control group, mRNA and protein levels of Cthrc1, Wnt5a, ROR2, RhoA, Rac1, JNK, and ROCK were visibly up-regulated in the Ad-NONMMUGO148387 group. Our findings confirm that long non-coding RNA NONMMUG014387 can promote proliferation of Schwann cells surrounding the injury site through targeting Cthrc1 and activating the Wnt/PCP pathway.

    Related Articles | Metrics
    Notch pathway inhibitor DAPT enhances Atoh1 activity to generate new hair cells in situ in rat cochleae
    Wen-wei Luo, Zhao Han, Dong-dong Ren, Xin-wei Wang, Fang-lu Chi, Juan-mei Yang
    2017, 12 (12):  2092-2099.  doi: 10.4103/1673-5374.221169
    Abstract ( 241 )   PDF (1429KB) ( 302 )   Save

    Atoh1 overexpression in cochlear epithelium induces new hair cell formation. Use of adenovirus-mediated Atoh1 overexpression has mainly focused on the rat lesser epithelial ridge and induces ectopic hair cell regeneration. The sensory region of rat cochlea is difficult to transfect, thus new hair cells are rarely produced in situ in rat cochlear explants. After culturing rat cochleae in medium containing 10% fetal bovine serum, adenovirus successfully infected the sensory region as the width of the supporting cell area was significantly increased.Adenovirus encoding Atoh1 infected the sensory region and induced hair cell formation in situ. Combined application of the Notch inhibitor DAPT and Atoh1 increased the Atoh1 expression level and decreased hes1 and hes5 levels, further promoting hair cell generation. Our results demonstrate that DAPT enhances Atoh1 activity to promote hair cell regeneration in rat cochlear sensory epithelium in vitro.

    Related Articles | Metrics
     Quantification of intermuscular and intramuscular adipose tissue using magnetic resonance imaging after neurodegenerative disorders
    Madoka Ogawa, Robert Lester, Hiroshi Akima, Ashraf S. Gorgey
    2017, 12 (12):  2100-2105.  doi: 10.4103/1673-5374.221170
    Abstract ( 246 )   PDF (384KB) ( 1118 )   Save

    Ectopic adiposity has gained considerable attention because of its tight association with metabolic and cardiovascular health in persons with spinal cord injury (SCI). Ectopic adiposity is characterized by the storage of adipose tissue in non-subcutaneous sites. Magnetic resonance imaging (MRI) has proven to be an effective tool in quantifying ectopic adiposity and provides the opportunity to measure different adipose depots including intermuscular adipose tissue (IMAT) and intramuscular adipose tissue (IntraMAT) or intramuscular fat (IMF). It is highly important to distinguish and clearly define these compartments, because controversy still exists on how to accurately quantify these adipose depots. Investigators have relied on separating muscle from fat pixels based on their characteristic signal intensities. A common technique is plotting a threshold histogram that clearly separates between muscle and fat peaks. The cut-offs to separate between muscle and fat peaks are still not clearly defined and different cut-offs have been identified. This review will outline and compare the Midpoint and Otsu techniques, two methods used to determine the threshold between muscle and fat pixels on T1 weighted MRI. The process of water/fat segmentation using the Dixon method will also be outlined. We are hopeful that this review will trigger more research towards accurately quantifying ectopic adiposity due to its high relevance to cardiometabolic health after SCI.

    Related Articles | Metrics
    Roles of neural stem cells in the repair of peripheral nerve injury.
    Chong Wang, Chang-feng Lu, Jiang Peng, Cheng-dong Hu, Yu Wang
    2017, 12 (12):  2106-2112.  doi: 10.4103/1673-5374.221171
    Abstract ( 164 )   PDF (230KB) ( 324 )   Save

    Currently, researchers are using neural stem cell transplantation to promote regeneration after peripheral nerve injury, as neural stem cells play an important role in peripheral nerve injury repair. This article reviews recent research progress of the role of neural stem cells in the repair of peripheral nerve injury.Neural stem cells can not only differentiate into neurons, astrocytes and oligodendrocytes, but can also differentiate into Schwann-like cells, which promote neurite outgrowth around the injury. Transplanted neural stem cells can differentiate into motor neurons that innervate muscles and promote the recovery of neurological function. To promote the repair of peripheral nerve injury, neural stem cells secrete various neurotrophic factors, including brain-derived neurotrophic factor, fibroblast growth factor, nerve growth factor, insulin-like growth factor and hepatocyte growth factor. In addition, neural stem cells also promote regeneration of the axonal myelin sheath, angiogenesis, and immune regulation. It can be concluded that neural stem cells promote the repair of peripheral nerve injury through a variety of ways.

    Related Articles | Metrics