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    15 March 2019, Volume 14 Issue 3 Previous Issue    Next Issue
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    The role of Epstein-Barr virus in multiple sclerosis: from molecular pathophysiology to in vivo imaging
    Yi Guan,Dejan Jakimovski,Murali Ramanathan, Bianca Weinstock-Guttman, Robert Zivadinov
    2019, 14 (3):  373-386.  doi: 10.4103/1673-5374.245462
    Abstract ( 141 )   PDF (405KB) ( 242 )   Save

    Multiple sclerosis (MS) is a disease of the central nervous system characterized by inflammation, demyelination, and neuronal damage. Environmental and genetic factors are associated with the risk of developing MS, but the exact cause still remains unidentified. Epstein-Barr virus (EBV), vitamin D, and smoking are among the most well-established environmental risk factors in MS. Infectious mononucleosis, which is caused by delayed primary EBV infection, increases the risk of developing MS. EBV may also contribute to MS pathogenesis indirectly by activating silent human endogenous retrovirus-W. The emerging B-cell depleting therapies, particularly anti-CD20 agents such as rituximab, ocrelizumab, as well as the fully humanized ofatumumab, have shown promising clinical and magnetic resonance imaging benefit. One potential effect of these therapies is the depletion of memory B-cells, the primary reservoir site where EBV latency occurs. In addition, EBV potentially interacts with both genetic and other environmental factors to increase susceptibility and disease severity of MS. This review examines the role of EBV in MS pathophysiology and summarizes the recent clinical and radiological findings, with a focus on B-cells and in vivo imaging. Addressing the potential link between EBV and MS allows the better understanding of MS pathogenesis and helps to identify additional disease biomarkers that may be responsive to B-cell depleting intervention.

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    The metabolome identity: basis for discovery of biomarkers in neurodegeneration
    Julie-Myrtille Bourgognon, Joern R. Steinert
    2019, 14 (3):  387-390.  doi: 10.4103/1673-5374.245464
    Abstract ( 116 )   PDF (217KB) ( 160 )   Save

    Neurodegenerative disorders are often associated with cellular dysfunction caused by underlying protein-misfolding signalling. Numerous neuropathologies are diagnosed at late stage symptomatic changes which occur in response to these molecular malfunctions and treatment is often too late or restricted only to the slowing of further cell death. Important new strategies to identify early biomarkers with predictive value to intervene with disease progression at stages where cell dysfunction has not progressed irreversibly is of paramount importance. Thus, the identification of these markers presents an essential opportunity to identify and target disease pathways. This review highlights some important metabolic alterations detected in neurodegeneration caused by misfolded prion protein and discusses common toxicity pathways identified across different neurodegenerative diseases. Thus, having established some commonalities between various degenerative conditions, detectable metabolic changes may be of extreme value as an early diagnostic biomarker in disease.

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    Neuroinflammation as a target for glaucoma therapy
    Adornetto Annagrazia,Rossella Russo,Parisi Vincenzo
    2019, 14 (3):  391-394.  doi: 10.4103/1673-5374.245465
    Abstract ( 136 )   PDF (207KB) ( 150 )   Save

    The pathogenesis of glaucoma is still not fully clarified but a growing body of evidence suggests that neuroinflammation and immune response are part of the sequence of pathological events leading to the optic neuropathy. Indeed, inflammation - involving the activation and proliferation of resident glial cells (astrocytes, Muller cells and microglia) and the release of a plethora of anti- and pro-inflammatory cytokines, chemokines and reactive oxygen species - has been reported as common features in clinical and experimental glaucoma. In the insulted retina, as for other neuronal tissues, pathogenic and reparative aspects coexist in the inflammatory process, with extent and persistency affecting the final outcome. In view of this, therapies aimed at modulating the immune and inflammatory responses may represent a promising approach for limiting the optic nerve damage and the loss of retinal ganglion cells associated with glaucoma.

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    Basics on the use of acid-sensing ion channels’ inhibitors as therapeutics
    Jamileh Dibas, Houssam Al-Saad, Adnan Dibas
    2019, 14 (3):  395-398.  doi: 10.4103/1673-5374.245466
    Abstract ( 108 )   PDF (259KB) ( 175 )   Save

    Since the discovery of acid-sensing ion channels in 1997, their importance in the health of neurons and other non-neuronal cells has gained significant importance. Acid-sensing ion channels play important roles in mediating pain sensation during diseases such as stroke, inflammation, arthritis, cancer, and recently migraine. More interestingly, ASICs may explain the sex differences in pain between males and females. Also, the ability of acid-sensing ion channel blockers to exert neuroprotective effects in a number of neurodegenerative diseases has added a new dimension to their therapeutic value. The current failure rate of ~45% of new drugs (due to toxicity issues) and saving of up to 7 years in the life span of drug approval makes drug repurposing a high priority. If acid-sensing ion channels’ blockers undergo what is known as “drug repurposing”, there is a great potential to bring them as medications with known safety profiles to new patient populations. However, the route of administration remains a big challenge due to their poor penetration of the blood brain and retinal barriers. In this review, the promise of using acid-sensing ion channel blockers as neuroprotective drugs is discussed.

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    Role of axon resealing in retrograde neuronal death and regeneration after spinal cord injury
    William Rodemer,Michael E. Selzer
    2019, 14 (3):  399-404.  doi: 10.4103/1673-5374.245330
    Abstract ( 122 )   PDF (399KB) ( 187 )   Save

    Spinal cord injury leads to persistent behavioral deficits because mammalian central nervous system axons fail to regenerate. A neuron’s response to axon injury results from a complex interplay of neuron-intrinsic and environmental factors. The contribution of axotomy to the death of neurons in spinal cord injury is controversial because very remote axotomy is unlikely to result in neuronal death, whereas death of neurons near an injury may reflect environmental factors such as ischemia and inflammation. In lampreys, axotomy due to spinal cord injury results in delayed apoptosis of spinal-projecting neurons in the brain, beyond the extent of these environmental factors. This retrograde apoptosis correlates with delayed resealing of the axon, and can be reversed by inducing rapid membrane resealing with polyethylene glycol. Studies in mammals also suggest that polyethylene glycol may be neuroprotective, although the mechanism(s) remain unclear. This review examines the early, mechanical, responses to axon injury in both mammals and lampreys, and the potential of polyethylene glycol to reduce injury-induced pathology. Identifying the mechanisms underlying a neuron’s response to axotomy will potentially reveal new therapeutic targets to enhance regeneration and functional recovery in humans with spinal cord injury.

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    Rehabilitation following spinal cord injury: how animal models can help our understanding of exercise-induced neuroplasticity
    Kristina Loy,Florence M. Bareyre
    2019, 14 (3):  405-412.  doi: 10.4103/1673-5374.245951
    Abstract ( 116 )   PDF (1452KB) ( 202 )   Save

    Spinal cord injury is a devastating condition that is followed by long and often unsuccessful recovery after trauma. The state of the art approach to manage paralysis and concomitant impairments is rehabilitation, which is the only strategy that has proven to be effective and beneficial for the patients over the last decades. How rehabilitation influences the remodeling of spinal axonal connections in patients is important to understand, in order to better target these changes and define the optimal timing and onset of training. While clinically the answers to these questions remain difficult to obtain, rodent models of rehabilitation like bicycling, treadmill training, swimming, enriched environments or wheel running that mimic clinical rehabilitation can be helpful to reveal the axonal changes underlying motor recovery. This review will focus on the different animal models of spinal cord injury rehabilitation and the underlying changes in neuronal networks that are improved by exercise and rehabilitation.

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    The pig as a preclinical traumatic brain injury model: current models, functional outcome measures, and translational detection strategies
    Holly A. Kinder,Emily W. Baker,Franklin D. West
    2019, 14 (3):  413-424.  doi: 10.4103/1673-5374.245334
    Abstract ( 199 )   PDF (544KB) ( 1008 )   Save

    Traumatic brain injury (TBI) is a major contributor of long-term disability and a leading cause of death worldwide. A series of secondary injury cascades can contribute to cell death, tissue loss, and ultimately to the development of functional impairments. However, there are currently no effective therapeutic interventions that improve brain outcomes following TBI. As a result, a number of experimental TBI models have been developed to recapitulate TBI injury mechanisms and to test the efficacy of potential therapeutics. The pig model has recently come to the forefront as the pig brain is closer in size, structure, and composition to the human brain compared to traditional rodent models, making it an ideal large animal model to study TBI pathophysiology and functional outcomes. This review will focus on the shared characteristics between humans and pigs that make them ideal for modeling TBI and will review the three most common pig TBI models–the diffuse axonal injury, the controlled cortical impact, and the fluid percussion models. It will also review current advances in functional outcome assessment measures and other non-invasive, translational TBI detection and measurement tools like biomarker analysis and magnetic resonance imaging. The use of pigs as TBI models and the continued development and improvement of translational assessment modalities have made significant contributions to unraveling the complex cascade of TBI sequela and provide an important means to study potential clinically relevant therapeutic interventions.

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    On the development of optical peripheral nerve interfaces
    Hans E. Anderson,Richard F. ff. Weir
    2019, 14 (3):  425-436.  doi: 10.4103/1673-5374.245461
    Abstract ( 117 )   PDF (596KB) ( 253 )   Save

    Limb loss and spinal cord injury are two debilitating conditions that continue to grow in prevalence. Prosthetic limbs and limb reanimation present two ways of providing affected individuals with means to interact in the world. These techniques are both dependent on a robust interface with the peripheral nerve. Current methods for interfacing with the peripheral nerve tend to suffer from low specificity, high latency and insufficient robustness for a chronic implant. An optical peripheral nerve interface may solve some of these problems by decreasing invasiveness and providing single axon specificity. In order to implement such an interface three elements are required: (1) a transducer capable of translating light into a neural stimulus or translating neural activity into changes in fluorescence, (2) a means for delivering said transducer and (3) a microscope for providing the stimulus light and detecting the fluorescence change. There are continued improvements in both genetically encoded calcium and voltage indicators as well as new optogenetic actuators for stimulation. Similarly, improvements in specificity of viral vectors continue to improve expression in the axons of the peripheral nerve. Our work has recently shown that it is possible to virally transduce axons of the peripheral nerve for recording from small fibers. The improvements of these components make an optical peripheral nerve interface a rapidly approaching alternative to current methods.

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     Multitarget therapeutic strategies for Alzheimer’s disease
    Mostafa M. Ibrahim, Moustafa T. Gabr
    2019, 14 (3):  437-440.  doi: 10.4103/1673-5374.245463
    Abstract ( 121 )   PDF (358KB) ( 149 )   Save

    Neurodegenerative diseases such as Alzheimer’s, Huntington’s and Parkinson’s diseases have multifaceted nature because of the different factors contributing to their progression. The complex nature of neurodegenerative diseases has developed a pressing need to design multitarget-directed ligands to address the complementary pathways involved in these diseases. The major enzyme targets for development of therapeutics for Alzheimer’s disease are cholinesterase and β-secretase enzymes. In this review, we discuss recent advances in profiling single target inhibitors based on these enzymes to multitarget-directed ligands as potential therapeutics for this devastating disease. In addition, therapeutics based on iron chelation strategy are discussed as well.

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    Essential oils and functional herbs for healthy aging
    Snezana Agatonovic-Kustrin,Ella Kustrin,David W. Morton
    2019, 14 (3):  441-445.  doi: 10.4103/1673-5374.245467
    Abstract ( 145 )   PDF (454KB) ( 219 )   Save

    As total life expectancy increases, the prevalence of age-related diseases such as diabetes and Alzheimer’s disease is also increasing. Many hypotheses about Alzheimer’s disease have been developed, including cholinergic neuron damage, oxidative stress, and inflammation. Acetylcholine is a major neurotransmitter in the brain and cholinergic deficits leads to cognitive dysfunction and decline. Recent studies have linked diabetes as a risk factor in developing Alzheimer’s disease and other types of dementia. The incidence of patients with type II diabetes and increased levels and activity of α-amylase is higher in patients with dementia. It has been shown that aromatherapy with essential oils from the mint family can improve cognitive performance in Alzheimer’s disease patients. Selected monoterpenoids from these essential oils are reported to inhibit acetylcholinesterase, both in vitro and in vivo. Terpenoids are small, fat-soluble organic molecules that can transfer across nasal mucosa if inhaled, or penetrate through the skin after topical application, enter into the blood and cross the blood-brain barrier. Recent evidence supports the idea that the common constituents of essential oils also inhibit α-amylase, a starch digestive enzyme that plays an important role in the control of diabetes. The mint family is a fragrant plant family that contains most of the culinary herbs found in the Mediterranean diet. The Mediterranean diet is considered to be one of the healthiest diets in the world, and is found to be beneficial not only for the heart but also for the brain. Herbs used in this diet are rich in antioxidants that can prevent oxidative damage caused by free radicals. However, our study shows that they also contain biologically active compounds with potent α-amylase and acetylcholinesterase inhibitory activities. Consumption of fresh herbs can help boost memory and reduce sugar levels in the body. The use of herbs as a functional food could lead to significant improvements in health. Cognitive stimulation with medical food and medical herbs could delay development of cognitive decline, and improve the quality of life of Alzheimer’s disease patients. This effect can be enhanced if combined with aromatherapy, topically or by inhalation, and/or by ingestion. Terpenes and terpenoids, the primary constituents of these essential oils are small, lipid soluble organic molecules that can be absorbed through the skin or across nasal mucosa into the systemic blood circulation. Many terpenes can also cross the blood-brain barrier. Therefore, topical application or inhalation of essential oils will also produce a systemic effect.

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    In vivo imaging of structural, metabolic and functional brain changes in glaucoma
    Anisha Kasi,Muneeb A. Faiq,Kevin C. Chan
    2019, 14 (3):  446-449.  doi: 10.4103/1673-5374.243712
    Abstract ( 125 )   PDF (848KB) ( 191 )   Save

    Glaucoma, the world’s leading cause of irreversible blindness, is a condition for which elevated intraocular pressure is currently the only modifiable risk factor. However, the disorder can continue to progress even at reduced intraocular pressure. This indicates additional key factors that contribute to the etiopathogenesis. There has been a growing amount of literature suggesting glaucoma as a neurodegenerative disease of the visual system. However, it remains debatable whether the observed pathophysiological conditions are causes or consequences. This review summarizes recent in vivo imaging studies that helped advance the understanding of early glaucoma involvements and disease progression in the brains of humans and experimental animal models. In particular, we focused on the non-invasive detection of early structural and functional brain changes before substantial clinical visual field loss in glaucoma patients; the eye-brain interactions across disease severity; the metabolic changes occurring in the brain’s visual system in glaucoma; and, the widespread brain involvements beyond the visual pathway as well as the potential behavioral relevance. If the mechanisms of glaucomatous brain changes are reliably identified, novel neurotherapeutics that target parameters beyond intraocular pressure lowering can be the promise of the near future, which would lead to reduced prevalence of this irreversible but preventable disease.

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    Combining anti-inflammatory and unfolding protein responses to fight stroke
    Berta Anuncibay-Soto, Enrique Font-Belmonte, Arsenio Fernández-López
    2019, 14 (3):  450-451.  doi: 10.4103/1673-5374.245468
    Abstract ( 113 )   PDF (360KB) ( 156 )   Save

    This perspective shows an attempt to obtain synergy effects to fight ischemic stroke by combining agents acting on two different homeo-static mechanisms: inflammation and unfolded protein response. Different pharmacological approaches have been assayed to alleviate cerebrovascular accident (stroke), which represents one of the most devastating diseases in the elderly. There are two main types of cerebrovascular accidents: ischemic and hemorrhagic strokes. The former, reaching up to 87% of incidences, represents the most relevant form of cerebrovascular accident. The deprivation of glucose and oxygen due to ischemia results in a lack of energy in cells that leads them to activate mechanisms to recover homeostasis or to death if they cannot overcome the damage. In this regard, after the blood flow in a specific area of the brain is blocked (focal ischemia), two areas can be detected in the injured tissue: the ischemic core, where blood flow is reduced to less than 7 mL/100 g per minute and the penumbra area where some blood flow (7–17 mL/100 g per minute) remains. The ischemic core is characterized by the presence of necrosis, an immediate, irreversible and non-reg-ulated type of cell death. The penumbra surrounds the ischemic core, and presents regulated cell death subroutines such as apoptosis or necroptosis. The delayed cell death in the penumbra area provides some opportunities to prevent the neuronal demise and a consider-able effort in research has been focused on limiting the damage in this area. The global cerebral ischemia model where blood flow is blocked to the whole brain for a short time does not present an ischemic core and can be considered as a penumbra model for the whole brain. Thus, this model is very useful for comparing the responses of different areas of the brain to ischemia and in pharmacological research aimed to look for therapies that rescue the damaged cells in the penumbra area.

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    Neuroprotective effect of Notch pathway inhibitor DAPT against focal cerebral ischemia/reperfusion 3 hours before model establishment
    Jun-Jie Wang, Jun-De Zhu,Xian-Hu Zhang, Ting-Ting Long, Guo Ge, Yan Yu
    2019, 14 (3):  452-461.  doi: 10.4103/1673-5374.245469
    Abstract ( 127 )   PDF (2492KB) ( 246 )   Save

    As an inhibitor of the Notch signaling pathway, N-[N-(3,5-difluorohenacetyl)-l-alanyl]-S-phenylglycine tert-butyl ester (DAPT) may protect brain tissue from serious ischemic injury. This study aimed to explore neuroprotection by DAPT after cerebral ischemia/reperfusion (I/R) injury. DAPT was intraperitoneally injected 3 hours before the establishment of a focal cerebral I/R model in the right middle cerebral artery of obstructed mice. Longa scores were used to assess neurological changes of mice. Nissl staining and TdT-mediated dUTP-biotin nick-end labeling staining were used to examine neuronal damage and cell apoptosis in the right prefrontal cortex, while immunofluorescence staining was used to detect glial fibrillary acidic protein- and Notch1-positive cells. Protein expression levels of Hes1 and Hes5 were detected by western blot assay in the right prefrontal cortex. Our results demonstrated that DAPT significantly improved neurobehavioral scores and relieved neuronal morphological damage. DAPT decreased the number of glial fibrillary acidic protein- and Notch1-positive cells in the right prefrontal cortex, while also reducing the number of apoptotic cells and decreasing interleukin-6 and tumor necrosis factor-α contents, and simultaneously downregulating Hes1 and Hes5 protein expression. These findings verify that DAPT alleviates pathological lesions and strengthens the anti-inflammatory response after cerebral I/R injury. Thus, DAPT might be developed as an effective drug for the prevention of cerebral I/R injury.

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    An enriched environment promotes synaptic plasticity and cognitive recovery after permanent middle cerebral artery occlusion in mice
    Chuan-Jie Wang, Yi Wu,Qun Zhang, Ke-Wei Yu, Yu-Yang Wang
    2019, 14 (3):  462-469.  doi: 10.4103/1673-5374.245470
    Abstract ( 119 )   PDF (918KB) ( 198 )   Save

    Cerebral ischemia activates an endogenous repair program that induces plastic changes in neurons. In this study, we investigated the effects of environmental enrichment on spatial learning and memory as well as on synaptic remodeling in a mouse model of chronic cerebral ischemia, produced by subjecting adult male C57BL/6 mice to permanent left middle cerebral artery occlusion. Three days post¬operatively, mice were randomly assigned to the environmental enrichment and standard housing groups. Mice in the standard housing group were housed and fed a standard diet. Mice in the environmental enrichment group were housed in a cage with various toys and fed a standard diet. Then, 28 days postoperatively, spatial learning and memory were tested using the Morris water maze. The expression levels of growth-associated protein 43, synaptophysin and postsynaptic density protein 95 in the hippocampus were analyzed by western blot assay. The number of synapses was evaluated by electron microscopy. In the water maze test, mice in the environmental enrichment group had a shorter escape latency, traveled markedly longer distances, spent more time in the correct quadrant (northeast zone), and had a higher frequency of crossings compared with the standard housing group. The expression levels of growth-associated protein 43, synaptophysin and postsynaptic density protein 95 were substantially upregulated in the hippocampus in the environmental enrichment group compared with the standard housing group. Furthermore, electron microscopy revealed that environmental enrichment increased the number of synapses in the hippocampal CA1 region. Collectively, these findings suggest that environmental enrichment ameliorates the spatial learning and memory impairment induced by permanent middle cerebral artery occlusion. Environmental enrichment in mice with cerebral ischemia likely promotes cognitive recovery by inducing plastic changes in synapses.

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    Xiao-Xu-Ming decoction extract regulates differentially expressed proteins in the hippocampus after chronic cerebral hypoperfusion
    Yue-Hua Wang,Ying-Lin Yang,Xiao Cheng,Jun Zhang,Wan Li,Guan-Hua Du
    2019, 14 (3):  470-479.  doi: 10.4103/1673-5374.245471
    Abstract ( 151 )   PDF (2821KB) ( 247 )   Save

    Xiao-Xu-Ming decoction has been widely used to treat stroke and sequelae of stroke. We have previously shown that the active fractions of Xiao-Xu-Ming decoction attenuate cerebral ischemic injury. However, the global protein profile and signaling conduction pathways reg­ulated by Xiao-Xu-Ming decoction are still unclear. This study established a two-vessel occlusion rat model by bilateral common carotid artery occlusion. Rats were intragastrically administered 50 or 150 mg/kg Xiao-Xu-Ming decoction for 4 consecutive weeks. Learning and memory abilities were measured with Morris water maze. Motor ability was detected with prehensile test. Coordination ability was exam­ined using the inclined screen test. Neuronal plasticity was observed by immunofluorescent staining. Differentially expressed proteins of rat hippocampus were analyzed by label-free quantitative proteomics. Real time-polymerase chain reaction and western blot assay were used to identify the changes in proteins. Results showed that Xiao-Xu-Ming decoction dramatically alleviated learning and memory deficits, and motor and coordination dysfunction, and increased the expression of microtubule-associated protein 2. Xiao-Xu-Ming decoction extract remarkably decreased 13 upregulated proteins and increased 39 downregulated proteins. The regulated proteins were mainly involved in oxidation reduction process, intracellular signaling cascade process, and protein catabolic process. The signaling pathways were mainly involved in ubiquitin mediated proteolysis and the phosphatidylinositol signaling system. Furthermore, there was an interaction among Rab2a, Ptpn1, Ppm1e, Cdk18, Gorasp2, Eps15, Capza2, Syngap1 and Mt-nd1. Protein analyses confirmed the changes in expression of MT-ND1. The current findings provide new insights into the molecular mechanisms of Xiao-Xu-Ming decoction extract’s effects on chronic cerebral hypoperfusion.

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    Sodium valproate suppresses abnormal neurogenesis induced by convulsive status epilepticus
    Peng Wu, Yue Hu,Xiu-Juan Li,Min Cheng, Li Jiang
    2019, 14 (3):  480-484.  doi: 10.4103/1673-5374.245475
    Abstract ( 127 )   PDF (747KB) ( 140 )   Save

    Status epilepticus has been shown to activate the proliferation of neural stem cells in the hippocampus of the brain, while also causing a large amount of neuronal death, especially in the subgranular zone of the dentate gyrus and the subventricular zone. Simultaneously, proliferating stem cells tend to migrate to areas with obvious damage. Our previous studies have clearly confirmed the effect of sodium valproate on cognitive function in rats with convulsive status epilepticus. However, whether neurogenesis can play a role in the antiepileptic effect of sodium valproate remains unknown. A model of convulsive status epilepticus was established in Wistar rats by intraperitoneal injection of 3 mEq/kg lithium chloride, and intraperitoneal injection of pilocarpine 40 mg/kg after 18–20 hours. Sodium valproate (100, 200, 300, 400, 500, or 600 mg/kg) was intragastrically administered six times every day (4-hour intervals) for 5 days. To determine the best dosage, sodium valproate concentration was measured from the plasma. The effective concentration of sodium valproate in the plasma of the rats that received the 300-mg/kg interven¬tion was 82.26 ± 11.23 μg/mL. Thus, 300 mg/kg was subsequently used as the intervention concentration of sodium valproate. The following changes were seen: Recording excitatory postsynaptic potentials in the CA1 region revealed high-frequency stimulation-induced long-term po¬tentiation. Immunohistochemical staining for BrdU-positive cells in the brain revealed that sodium valproate intervention markedly increased the success rate and the duration of induced long-term potentiation in rats with convulsive status epilepticus. The intervention also reduced the number of newborn neurons in the subgranular area of the hippocampus and subventricular zone and inhibited the migration of newborn neu¬rons to the dentate gyrus. These results indicate that sodium valproate can effectively inhibit the abnormal proliferation and migration of neural stem cells and newborn neurons after convulsive status epilepticus, and improve learning and memory ability.

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    Impaired energy metabolism after oxygen-glucose deprivation in immature cerebellar granular neurons exposed to ethanol
    Ana Spataru,Diana Le Duc,Leon Zagrean, Ana-Maria Zagrean
    2019, 14 (3):  485-490.  doi: 10.4103/1673-5374.245474
    Abstract ( 119 )   PDF (637KB) ( 174 )   Save

    Alcohol, a widely abused drug, has deleterious effects on the immature nervous system. This study investigates the effect of chronic in vitro ethanol exposure on the metabolism of immature rat cerebellar granular cells (CGCs) and on their response to oxygen-glucose deprivation (OGD). Primary CGC cultures were exposed to ethanol (100 mM in culture medium) or to control ethanol-free medium starting day one in vitro (DIV1). At DIV8, the expression of ATP synthase gene ATP5g3 was quantified using real-time PCR, then cultures were exposed to 3 hours of OGD or normoxic conditions. Subsequently, cellular metabolism was assessed by a resazurin assay and by ATP level measurement. ATP5g3 expression was reduced by 12-fold (P = 0.03) and resazurin metabolism and ATP level were decreased to 74.4 ± 4.6% and 55.5 ± 6.9%, respectively after chronic ethanol treatment compared to control values (P < 0.01). Additionally, after OGD exposure of ethanol-treated cultures, resazurin metabolism and ATP level were decreased to 12.7 ± 1.0% and 9.0 ± 2.0% from control values (P < 0.01). These results suggest that chronic ethanol exposure reduces the cellular ATP level, possibly through a gene expression down-regulation mechanism, and increases the vulnerability to oxygen-glucose deprivation. Thus, interventions which improve metabolic function and sustain ATP-levels could attenuate ethanol-induced neuronal dysfunction and should be addressed in future studies.

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    Paternal physical exercise modulates global DNA methylation status in the hippocampus of male rat offspring
    Christiano Spindler, Ethiane Segabinazi, André Luís Ferreira de Meireles, Francele Valente Piazza, Filipe Mega, Gabriela dos Santos Salvalaggio, Matilde Achaval, Viviane Rostirola Elsner, Simone Marcuzzo
    2019, 14 (3):  491-500.  doi: 10.4103/1673-5374.245473
    Abstract ( 126 )   PDF (919KB) ( 242 )   Save

    It is widely known that maternal physical exercise is able to induce beneficial improvements in offspring cognition; however, the effects of paternal exercise have not been explored in detail. The present study was designed to evaluate the impact of paternal physical exercise on memory and learning, neuroplasticity and DNA methylation levels in the hippocampus of male offspring. Adult male Wistar rats were divided into two groups: sedentary or exercised fathers. The paternal preconception exercise protocol consisted of treadmill running, 20 minutes daily, 5 consecutive days per week for 22 days, while the mothers were not trained. After mating, paternal sperm was collected for global DNA methylation analysis. At postnatal day 53, the offspring were euthanized, and the hippocampus was dissected to measure cell survival by 5-bromo-2’-deoxiuridine and to determine the expression of synaptophysin, reelin, brain-derived neurotrophic factor and global DNA methylation levels. To measure spatial memory and learning changes in offspring, the Morris water maze paradigm was used. There was an improvement in spatial learning, as well as a significant decrease in hippocampal global DNA methylation levels in the offspring from exercised fathers compared with those from sedentary ones; however, no changes were observed in neuroplasticity biomarkers brain-derived neurotrophic factor, reelin and 5-bromo-2′-deoxiuridine. Finally, the global DNA methylation of paternal sperm was not significantly changed by physical exercise. These results suggest a link between paternal preconception physical activity and cognitive benefit, which may be associated with hippocampal epigenetic programming in male offspring. However, the biological mechanisms of this modulation remain unclear.

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    Plasmid-based generation of neural cells from human fibroblasts using non-integrating episomal vectors
    Shao-Bing Dai, Ting Shen,Ting-Ting Zheng,Jia-Li Pu,Xin-Zhong Chen
    2019, 14 (3):  501-505.  doi: 10.4103/1673-5374.245476
    Abstract ( 119 )   PDF (739KB) ( 150 )   Save

    Differentiation of human fibroblasts into functional neurons depends on the introduction of viral-mediated transcription factors, which present risks of viral gene integration and tumorigenicity. In recent years, although some studies have been successful in directly inducing neurons through sustained expression of small molecule compounds, they have only been shown to be effective on mouse-derived cells. Thus, herein we delivered vectors containing Epstein-Barr virus-derived oriP/Epstein-Barr nuclear antigen 1 encoding the neuronal tran¬scription factor, Ascl1, the neuron-specific microRNA, miR124, and a small hairpin directed against p53, into human fibroblasts. Cells were incubated in a neuron-inducing culture medium. Immunofluorescence staining was used to detect Tuj-1, microtubule-associated protein 2, neuron-specific nucleoprotein NeuN and nerve cell adhesion molecules in the induced cells. The proportion of Tuj1-positive cells was up to 36.7% after induction for 11 days. From day 21, these induced neurons showed neuron-specific expression patterns of mi-crotubule-associated protein 2, NeuN and neural cell adhesion molecule. Our approach is a simple, plasmid-based process that enables direct reprogramming of human fibroblasts into neurons, and provides alternative avenues for disease modeling and neurodegenerative medicine.

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    Association of G-protein coupled purinergic receptor P2Y2 with ischemic stroke in a Han Chinese population of North China
    Li-Ying Yuan, Zhi-Yi He,Lei Li, Yan-Zhe Wang
    2019, 14 (3):  506-512.  doi: 10.4103/1673-5374.245472
    Abstract ( 121 )   PDF (303KB) ( 206 )   Save

    The G-protein-coupled purinergic receptor P2Y2 (P2RY2) plays an important role in the mechanism of atherosclerosis, which is relevant to ischemic stroke. This retrospective case-control study aimed to assess the relationship between P2RY2 gene polymorphisms and ischemic stroke risk in the northern Han Chinese population. In this study, clinical data and peripheral blood specimens were collected from 378 ischemic stroke patients and 344 controls. The ischemic stroke participants were recruited from the First Affiliated Hospital of China Med¬ical University and the First Affiliated Hospital of Liaoning Medical University. The controls were recruited from the Health Check Center at the First Affiliated Hospital of China Medical University. Ischemic stroke patients were divided into two subgroups according to the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) classification: large-artery atherosclerosis (n = 178) and small-artery occlusion (n = 200) strokes. All subjects were genotyped for three single nucleotide polymorphisms (rs4944831, rs1783596, and rs4944832) in the P2RY2 gene using peripheral venous blood samples. The distribution of the dominant rs4944832 phenotype (GG vs. GA+AA) differed significantly between small-artery occlusion patients and control subjects (odds ratio (OR) = 1.720, 95% confidence interval (CI): 1.203–2.458, P < 0.01). Multivariable logistic regression analysis revealed that the GG genotype of rs4944832 was significantly more prevalent in small-artery oc¬clusion patients than in control subjects (OR = 1.807, 95% CI: 1.215–2.687, P < 0.01). The overall distribution of the haplotype established by rs4944831-rs1783596-rs4944832 was significantly different between ischemic stroke patients and controls (P < 0.01). In ischemic stroke patients, the frequency of the G-C-G haplotype was significantly higher than in control subjects (P = 0.028), whereas the frequency of the T-C-A haplotype was lower than in control subjects (P = 0.047). These results indicate that the G-C-G haplotype of P2RY2 is a suscepti¬bility haplotype for ischemic stroke. In addition, the GG genotype of rs4944832 may be associated with the development of small-artery occlusion in the northern Han Chinese population. The study protocol was approved by the Ethics Committee of the First Affiliated Hos-pital of China Medical University on February 20, 2012 (No. 2012-38-1) and the First Affiliated Hospital of Liaoning Medical University, China, on March 1, 2013 (No. 2013-03-1). All participants gave their informed consent. This trial was registered with the ISRCTN Registry (ISRCTN11439124) on October 24, 2018. Protocol version (1.0).

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    3-N-Butylphthalide mitigates high glucose-induced injury to Schwann cells: association with nitrosation and apoptosis
    Dan-Dan Xu, Wen-Ting Li,Dan Jiang,Huai-Guo Wu,Ming-Shan Ren,Mei-Qiao Chen,Yuan-Bo Wu
    2019, 14 (3):  513-518.  doi: 10.4103/1673-5374.245590
    Abstract ( 140 )   PDF (392KB) ( 136 )   Save

    A high glucose state readily causes peripheral axon atrophy, demyelination, loss of nerve fiber function, and delayed regeneration. However, few studies have examined whether nitration is also critical for diabetic peripheral neuropathy. Therefore, this study investigated the effects of high glucose on proliferation, apoptosis, and 3-nitrotyrosine levels of Schwann cells treated with butylphthalide. In addition, we explored potential protective mechanisms of butylphthalide on peripheral nerves. Schwann cells were cultured in vitro with high glucose then stim¬ulated with the peroxynitrite anion inhibitors uric acid and 3-n-butylphthalide for 48 hours. Cell Counting Kit-8 and flow cytometry were used to investigate the effects of uric acid and 3-n-butylphthalide on proliferation and apoptosis of Schwann cells exposed to a high glucose environment. Effects of uric acid and 3-n-butylphthalide on levels of 3-nitrotyrosine in Schwann cells were detected by enzyme-linked im¬munosorbent assay. The results indicated that Schwann cells cultured in high glucose showed decreased proliferation, but increased apoptosis and intracellular 3-nitrotyrosine levels. However, intervention with uric acid or 3-n-butylphthalide could increase proliferation of Schwann cells cultured in high glucose, and inhibited apoptosis and intracellular 3-nitrotyrosine levels. According to our data, 3-n-butylphthalide may inhibit cell nitrification and apoptosis, and promote cell proliferation, thereby reducing damage to Schwann cells caused by high glucose.

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    Surgical treatment for severe cubital tunnel syndrome with absent sensory nerve conduction
    Jin-Song Tong, Zhen Dong,Bin Xu,Cheng-Gang Zhang, Yu-Dong Gu
    2019, 14 (3):  519-524.  doi: 10.4103/1673-5374.245479
    Abstract ( 193 )   PDF (270KB) ( 147 )   Save

    For severe cubital tunnel syndrome, patients with absent sensory nerve action potential tend to have more severe nerve damage than those without. Thus, it is speculated that such patients generally have a poor prognosis. How absent sensory nerve action potential affects sur¬gical outcomes remains uncertain owing to a scarcity of reports and conflicting results. One hundred and fourteen cases (88 patients with absent sensory nerve action potential and 26 patients with present sensory nerve action potential) were subjected to either subcutaneous transposition or in situ decompression. The minimum follow-up was set at 2 years. Primary outcome measures of overall hand function included their McGowan grade, modified Bishop score, and Disabilities of the Arm, Shoulder, and Hand Questionnaire (DASH) score. For patients with absent sensory nerve action potential, 71 cases (80.7%) achieved at least one McGowan grade improvement, 76 hands (86.4%) got good or excellent results according to the Bishop score, and the average DASH score improved 49.5 points preoperatively to 13.1 points postoperatively. When compared with the present sensory nerve action potential group, they showed higher postoperative Mc¬Gowan grades and DASH scores, but there was no statistical difference between the modified Bishop scores of the two groups. Following in situ decompression or subcutaneous transposition, great improvement in hand function was achieved for severe cubital tunnel syn¬drome patients with absent sensory nerve action potential. The functional outcomes after surgery for severe cubital tunnel syndrome are worse in patients with absent sensory nerve action potential than those without. This study was approved by the Ethical Committee of Hua shan Hospital, Fudan University, China (approval No. 2017142).

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    Increased levels of miR-3099 induced by peripheral nerve injury promote Schwann cell proliferation and migration
    Qian-Yan Liu,Yang Miao,Xing-Hui Wang,Pan Wang,Zhang-Chun Cheng,Tian-Mei Qian
    2019, 14 (3):  525-531.  doi: 10.4103/1673-5374.245478
    Abstract ( 148 )   PDF (2592KB) ( 212 )   Save

    MicroRNAs (miRNAs) can regulate the modulation of the phenotype of Schwann cells. Numerous novel miRNAs have been discovered and identified in rat sciatic nerve segments, including miR-3099. In the current study, miR-3099 expression levels following peripheral nerve injury were measured in the proximal stumps of rat sciatic nerves after surgical crush. Real-time reverse transcription-polymerase chain reaction was used to determine miR-3099 expression in the crushed nerve segment at 0, 1, 4, 7, and 14 days post sciatic nerve injury, which was consistent with Solexa sequencing outcomes. Expression of miR-3099 was up-regulated following peripheral nerve injury. EdU and tran¬swell chamber assays were used to observe the effect of miR-3099 on Schwann cell proliferation and migration. The results showed that increased miR-3099 expression promoted the proliferation and migration of Schwann cells. However, reduced miR-3099 expression sup¬pressed the proliferation and migration of Schwann cells. The potential target genes of miR-3099 were also investigated by bioinformatic tools and high-throughput outcomes. miR-3099 targets genes Aqp4, St8sia2, Tnfsf15, and Zbtb16 and affects the proliferation and mi¬gration of Schwann cells. This study examined the levels of miR-3099 at different time points following peripheral nerve injury. Our results confirmed that increased miR-3099 level induced by peripheral nerve injury can promote the proliferation and migration of Schwann cells.

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    Deferoxamine promotes recovery of traumatic spinal cord injury by inhibiting ferroptosis
    Xue Yao, Yan Zhang, Jian Hao, Hui-Quan Duan, Chen-Xi Zhao, Chao Sun, Bo Li, Bao-You Fan, Xu Wang, Wen-Xiang Li, Xuan-Hao Fu, Yong Hu, Chang Liu, Xiao-Hong Kong, Shi-Qing Feng
    2019, 14 (3):  532-541.  doi: 10.4103/1673-5374.245480
    Abstract ( 234 )   PDF (1988KB) ( 242 )   Save

    Ferroptosis is an iron-dependent novel cell death pathway. Deferoxamine, a ferroptosis inhibitor, has been reported to promote spinal cord injury repair. It has yet to be clarified whether ferroptosis inhibition represents the mechanism of action of Deferoxamine on spinal cord injury recovery. A rat model of Deferoxamine at thoracic 10 segment was established using a modified Allen’s method. Ninety 8-week-old female Wistar rats were used. Rats in the Deferoxamine group were intraperitoneally injected with 100 mg/kg Deferoxamine 30 minutes before injury. Simultaneously, the Sham and Deferoxamine groups served as controls. Drug administration was conducted for 7 consecutive days. The results were as follows: (1) Electron microscopy revealed shrunken mitochondria in the spinal cord injury group. (2) The Basso, Beattie and Bresnahan locomotor rating score showed that recovery of the hindlimb was remarkably better in the Deferox¬amine group than in the spinal cord injury group. (3) The iron concentration was lower in the Deferoxamine group than in the spinal cord injury group after injury. (4) Western blot assay revealed that, compared with the spinal cord injury group, GPX4, xCT, and glutathione expression was markedly increased in the Deferoxamine group. (5) Real-time polymerase chain reaction revealed that, compared with the Deferoxamine group, mRNA levels of ferroptosis-related genes Acyl-CoA synthetase family member 2 (ACSF2) and iron-responsive element-binding protein 2 (IREB2) were up-regulated in the Deferoxamine group. (6) Deferoxamine increased survival of neurons and inhibited gliosis. These findings confirm that Deferoxamine can repair spinal cord injury by inhibiting ferroptosis. Targeting ferroptosis is therefore a promising therapeutic approach for spinal cord injury.

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    Expression and localization of absent in melanoma 2 in the injured spinal cord
    Sai-Nan Wang,Xue-Yan Guo,Jie Tang,Shu-Qin Ding,Lin Shen,Rui Wang,Shan-Feng Ma,Jian-Guo Hu,He-Zuo Lü
    2019, 14 (3):  542-552.  doi: 10.4103/1673-5374.245481
    Abstract ( 128 )   PDF (29738KB) ( 116 )   Save

    In traumatic brain injury, absent in melanoma 2 (AIM2) has been demonstrated to be involved in pyroptotic neuronal cell death. Al¬though the pathophysiological mechanism of spinal cord injury is similar to that of brain injury, the expression and cellular localization of AIM2 after spinal cord injury is still not very clear. In the present study, we used a rat model of T9 spinal cord contusive injury, produced using the weight drop method. The rats were randomly divided into 1-hour, 6-hour, 1-day, 3-day and 6-day (post-injury time points) groups. Sham-operated rats only received laminectomy at T9 without contusive injury. Western blot assay revealed that the expression levels of AIM2 were not significantly different among the 1-hour, 6-hour and 1-day groups. The expression levels of AIM2 were markedly higher in the 1-hour, 6-hour and 1-day groups compared with the sham, 3-day and 7-day groups. Double immunofluorescence staining demonstrated that AIM2 was expressed by NeuN+ (neurons), GFAP+ (astrocytes), CNPase+ (oligodendrocytes) and CD11b+ (microglia) cells in the sham-operated spinal cord. In rats with spinal cord injury, AIM2 was also found in CD45+ (leukocytes) and CD68+ (activated microglia/macrophages) cells in the spinal cord at all time points. These findings indicate that AIM2 is mainly expressed in neurons, astro¬cytes, microglia and oligodendrocytes in the normal spinal cord, and that after spinal cord injury, its expression increases because of the infiltration of leukocytes and the activation of astrocytes and microglia/macrophages.

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