牛磺酸对大鼠局灶性脑缺血的神经保护作用

目的 观察牛磺酸对大鼠持续性局灶性脑缺血的影响。方法 采用大脑中动脉线栓法制备大鼠局灶性脑缺血模型 ,随机分为假手术组、缺血模型组和牛磺酸 (2 5 0mg·kg-1·d-1)治疗组 ,持续缺血 6h后观测各组的神经行为变化 ,脑梗死体积 ,脑组织丙二醛 (malondialdehyde ,MDA)含量和超氧化物歧化酶 (superoxidedismutase,SOD)活性 ,一氧化氮合酶 (nitricoxidesynthetase,NOS)含量及表达 ,细胞间粘附分子 1(inter cellularadhesionmolecule 1,ICAM 1)的表达。结果 ①牛磺酸可以改善大鼠持续性局灶性脑缺血引起的神经行为障碍 ,减少脑梗死体积 ;②可以提高脑组织SOD活性 ,但对MDA水平未见明显影响 ;③对脑组织NOS含量及表达未见明显影响 ;④明显减少ICAM 1阳性血管计数。结论 牛磺酸可通过增强脑组织SOD活性 ,提高清除氧自由基能力 ,以及减少脑缺血引起的ICAM 1表达 ,从而减轻脑缺血后的炎症反应 。

Neuroprotective Effects of Modafinil on MPTP Mouse Model of Parkinson′s Disease

Aim To observe the neuroprotective effects of modafinil on the Parkinson'sdisease ( PD ) model induced by 1-methyl-4-phenyl-1, 2,3, 6-tetrahydropyridine (MPTP ). Methods Themodel of PD was induced by intraperitoneal injection of MPTP into C57BL/6J mice for 4 d. Modafinil(ip, 50 or 100 mg·kg^(-1)·d^(-1)) was administered following MPTP for 4 d and for another 10 dconsecatirely. The effects of modafinil on the locomotor activity, and the incubation, maintenanceperiod and grade of the tremor, the duration of the climbing rod of mouse, and the distribution ofpositive cells of ty-rosine hydroxylase (TH) and Nissl bodies in the striatum and substantia nigra(SN) were observed. The contents of dopam-ine (DA) , noradrenaline (NA) and 5-hydroxytryptamine(5-HT) in the striatum were determined. Results Modafinil (50 and 100 mg·kg^(-1)) significantlyprevented the locomotor, the tremor and climbing rod defect behavior in a dose-dependent manner (P <0.05 and P < 0.01, n = 10), prevented the decrease in the number of TH-positive cells and Nisslbodies (P<0.05, n=10), and reduced the decrease of DA, NA, and 5-HT in the striatum (P < 0.05, n =10) induced by MPTP. Conclusion Modafinil improves the behavioral deficits and prevents themonoaminergic neuron lesion in seriously impaired MPTP mouse model.

Neuroprotective action of Ginkgo biloba on the enteric nervous system of diabetic rats

AIM: To investigate the effect of Ginkgo biloba extract on the enteric neurons in the small intestine of diabetic rats. METHODS: Fifteen Wistar rats were divided into three groups: control group (C), diabetic group (D) and diabetic-treated (DT) daily with EGb 761 extract (50 mg/kg body weight) for 120 d. The enteric neurons were identified by the myosin-V immunohistochemical technique. The neuronal density and the cell body area were also analyzed. RESULTS: There was a significant decrease in the neuronal population (myenteric plexus P = 0.0351; submucous plexus P = 0.0217) in both plexuses of the jejunum in group D when compared to group C. With regard to the ileum, there was a significant decrease (P = 0.0117) only in the myenteric plexus. The DT group showed preservation of the neuronal population in the jejunum submucous plexus and in the myenteric plexus in the ileum. The cell body area in group D increased significantly (P = 0.0001) in the myenteric plexus of both segments studied as well as in the ileum submucosal plexus, when compared to C. The treatment reduced (P = 0.0001) the cell body area of the submucosal neurons of both segments and the jejunum myenteric neurons. CONCLUSION: The purified Ginkgo biloba extract has a neuroprotective effect on the jejunum submucous plexus and the myenteric plexus of the ileum of diabetic rats.

INTRANASAL DELIVERY OF NERVE GROWTH FACTOR TO PROTECT THE CENTRAL NERVOUS SYSTEM AGAINST ACUTE CEREBRAL INFARCTION

Objective To confirmed reliability and feasibility of intranasal nerve growth factor (NGF) bypassing the blood-brain barrier and its potential neuroprotective effects on acute cerebral ischemia. Methods (1) To assay NGF concentrations in different brain regions after middle cerebral artery occlusion (MCAO).Rats were randomly divided into intranasal (IN) NGF, intravenous (IV) NGF, and untreated group (n= 4). The concentra-tions of NGF of different brain regions in the three groups after MCAO were measured by ELISA. (2) To observe neuro-protective action of NGF on focal cerebral ischemic damage. Rats were randomly assigned to 4 groups: IN vehicle, IN NGF, IV vehicle, IV NGF (n= 8). Treatment was initiated 30 minutes after onset of MCAO and given again 24 hours later. Three neurologic behavioral tests were performed 24 and 48 hours following onset of MCAO. Corrected infarct volumes were determined 48 hours after onset of MCAO. Results The olfactory bulb in IN NGF group obtained the highest concentration (3252 pg/g) of NGF among all regions, followed by the hippocampus. The NGF concentrations in the olfactory bulb and hippocampus in IN NGF group were markedly higher than that in IV NGF and control groups. The infarct volume in IN NGF group was markedly reduced by 38.8% compared with IN vehicle group. IN NGF group vestibulum function markedly improved compared with IN vehicle group at 24 and 48 hours after onset of MCAO (P 24 h = 0.02 and P 48 h = 0.04, respectively). Conclusion Intranasal NGF could pass through the blood-brain barrier, reach the central nervous system, reduce infarct volume, and improve neurologic function in rats following MCAO. Intranasal delivery of NGF may be a promising treat-ment for stroke.

Using the endocannabinoid system as a neuroprotective strategy in perinatal hypoxic-ischemic brain injury

One of the most important causes of brain injury in the neonatal period is a perinatal hypoxicischemic event.This devastating condition can lead to long-term neurological deficits or even death.After hypoxic-ischemic brain injury,a variety of specific cellular mechanisms are set in motion,triggering cell damage and finally producing cell death.Effective therapeutic treatments against this phenomenon are still unavailable because of complex molecular mechanisms underlying hypoxic-ischemic brain injury.After a thorough understanding of the mechanism underlying neural plasticity following hypoxic-ischemic brain injury,various neuroprotective therapies have been developed for alleviating brain injury and improving long-term outcomes.Among them,the endocannabinoid system emerges as a natural system of neuroprotection.The endocannabinoid system modulates a wide range of physiological processes in mammals and has demonstrated neuroprotective effects in different paradigms of acute brain injury,acting as a natural neuroprotectant.The aim of this review is to study the use of different therapies to induce long-term therapeutic effects after hypoxic-ischemic brain injury,and analyze the important role of the endocannabinoid system as a new neuroprotective strategy against perinatal hypoxic-ischemic brain injury.

Chemical constituents isolated from the aerial parts of Swertia pseudochinensis and their potential neuroprotective effects

Objective:Swertia pseudochinensis,an annual herb of the genus Swertia in the family Gentianaceae.Some constituents and extracts from the Swertia genus have been recently reported to possess neuroprotective effects,suggesting their potential utility in the prevention and treatment of Parkinson disease(PD).The aim of this work is to identify the chemical constituents and evaluate the potential biological activists of Swertia pseudochinensis.Methods:The phytochemicals from the aerial parts of S.pseudochinensis were isolated and purified by silica gel,Sephadex LH-20 gel,semi-preparative high-performance liquid chromatography,and identified by the spectroscopic methods.All compounds were evaluated for their potential neuroprotective effects against 1-methyl-4-phenylpyridinium-induced apoptosis in the SH-SY5Y human neuroblastoma cell line using the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay.Then,we performed an enrichment analysis using the Database for Annotation,Visualization,and Integrated Discovery and investigated the mechanisms by which bellidifolin regulates neurodegenerative disease.Results:Two new anthraquinone,1,5,6-trimethoxy-2-hydroxy-3-methy-anthraquinone(1)and 1,5,6,8-tetramethoxy-2-hydroxy-3-methyanthraquinone(2),together with nine known including 7-O-b-d-glucopyranosyl-1,8-dihydroxy-3-methoxyxanthone(3),gentisin(4),swertianolin(5),bellidifolin(6),gentiacaulein(7),norswertianolin(8),5-O-b-d-glucopyranosyl-1,3,8-trihydroxyapatone(9),1-hydroxy-3,5,8-trimethoxyxanthone(10),and aurantio-obtusin(11),were isolated and compounds 6–8 and 10 exhibited neuroprotective effects at a concentration of 50mmol/L.Among them,bellidifolin showed significant protective activity,and might have potential as a neuroprotective agent for the treatment of PD,possibly by acting on oxidative damage and reactive oxygen species.Conclusions:These findings indicate that further research on the genus Swertia and its bioactive constituents toward neurodegenerative disorders could be extremely rewarding.

PROTECTIVE EFFECT OF MELATONIN ON NEURAL CELLS AGAINST THE CYTOTOXICITY OF OXYRADICALS

BZ]To investigate the exact mechanism of melatonin to prohibit the apoptosis of neural cells induced by various kinds of cytotoxic agents. [WT5”BX]Methods. [WT5”BZ]We used the methods of phase contrast microscopy, MTT assay and hoechst dye staining to check this mechanism in SKNSH and U251 cell lines. [WT5”BX]Results. Both 2mmol/L H 2O 2 and 0 5 μ mol/L amyloid β protein (Aβ) induce these two cell lines die via apoptosis. Either melatonin or glutathione can significantly protect both cell lines. The protective effect of 10 μ mol/L melatonin is as same as that of 60 μ mol/L glutathione. [WT5”BX]Conclusion. Melatonin can partly inhibit the cytotoxicity of H 2O 2 and Aβ through its role as a free radical scavenger.

Gastro-protective action of lafutidine mediated by capsaicin-sensitive afferent neurons without interaction with TRPV1 and involvement of endogenous prostaglandins

AIM： Lafutidine, a histamine H2 receptor antagonist, exhibits gastro-protective action mediated by capsaicinsensitive afferent neurons （CSN）. We compared the effect between lafutidine and capsaicin, with respect to the interaction with endogenous prostaglandins （PG）, nitric oxide （NO） and the afferent neurons, including transient receptor potential vanilloid subtype 1 （TRPV1）. METHODS： Male SD rats and C57BL/6 mice, both wildtype and prostacyclin IP receptor knockout animals, were used after 18 h of fasting. Gastric lesions were induced by the po administration of HCl/ethanol （60% in 150 mmol/L HCl） in a volume of 1 mL for rats or 0.3 mL for mice. RESULTS： Both lafutidine and capsaicin （1-10 mg/kg, po） afforded dose-dependent protection against HCI/ ethanol in rats and mice. The effects were attenuated by both the ablation of CSN and pretreatment with NG-nitro- L-arginine methyl ester, yet only the effect of capsaicin was mitigated by prior administration of capsazepine, the TRPV1 antagonist, as well as indomethacin. Lafutidine protected the stomach against HCl/ethanol in IP receptor knockout mice, similar to wild-type animals, while capsaicin failed to afford protection in the animals lacking IP receptors. Neither of these agents affected the mucosal PGE2 or 6-keto PGF1α contents in rat stomachs. Capsaicin evoked an increase in [Ca^2＋]i in rat TRPV1-transfected HEK293 cells while lafutidine did not. CONCLUSION： These results suggest that although both lafutidine and capsaicin exhibit gastro-protective action mediated by CSN, the mode of their effects differs regarding the dependency on endogenous PGs/IP receptors and TRPV1. It is assumed that lafutidine interacts with CSN at yet unidentified sites other than TRPV1.

Effect of flupirtine on the growth and viability of U373 malignant glioma cells

Objective： Flupirtine is a non-opioid analgesic without antipyretic or antiphlogistic properties but with favorable tolerability in humans. ＂Ibis analgesic also exhibits neuroprotective activities. Furthermore, flupirtine antagonizes glutamate- and . , 2＋ NMDA-mduced mtracellular levels of Ca and counteracts the effects of focal cerebral Lscherma. Although fluplrtme has been used to relieve pain caused by different diseases and clinical procedures, information on the safety and efficacy of flupirtine is limited. ＂fhe present study was conducted to investigate the neuroprotective effects of flupirtine on U373 malignant glioma （MG） cell lines. Methods： Cellviability and cell cycle analysis was performed by MTF assay and flow cytomet-,＇y, respectively. Results： Variations in the growth of U373 MG cells in $ mM N-methyl-D-aspartate （NMDA）, 1 mM flupirtine, and combined treatment indicated the antagonistic effects of NMDA and flupirtine on MG cell lines. The variation in the percentage of gated cellpopulation in different cell cycle phases showed significant variations after 48 h of treatment. Conclusion： Flupirtine has neuroprotective effect of on U373 MG cells, which limits its use in the pain management of brain tumors. This property warrants further studies using animal models and large-scale clinical trials.

Dual Isoflurane-induced Preconditioning Improves Neuroprotection in Rat Brain In Vitro and the Role of Extracellular Signal-regulated Protein Kinase

Objective To test the ability of isoflurane-induced preconditioning against oxygen and glucose dep- rivation （OGD） injury in vitro. Methods Rat hippocampal slices were exposed to 1 volume percentage （vol%）, 2vo1% or 3vo1% isoflurane respectively for 20 minutes under normoxic conditions （95% O2/5% CO2） once or twice （12 slices in each group） before OGD, with 15-minute washout after each exposure. During OGD experiments, hippocampus slices were bathed with artificial cerebrospinal fluid （ACSF） lacking glucose and perfused with 95% N2 and 5% CO2 for 14 minutes, followed by a 30-minute reperfusion in normal ACSF. The CA1 population spike （PS） was measured and used to quantify the degree of neuronal function recovery after OGD. To assess the role of mitogen-activated protein kinases （MAPKs） in isoflurane preconditioning, U0126, an inhibitor of extracellular signal-regulated protein kinase （ERK1/2）, and SB203580, an inhibitor of p38 MAPK, were used before two periods of 3vol% isoflurane exposure. Results The degree of neuronal function recovery of hippocampal slices exposed to 1 vol%, 2vol%, or 3vol% isoflurane once was 41.88%±9.23%, 55.05%±11.02%, or 63.18%±10.82% respectively. Moreover, neuronal function recovery of hippocampal slices exposed to 1 vol%, 2vo1%, or 3vo1% isoflurane twice was 53.75%±12.04%, 63.50%±11.06%, or 76.25%±12.25%, respectively. Isoflurane preconditioning increased the neuronal function recovery in a dose-dependent manner. U0126 blocked the preconditioning induced by dual exposure to 3vo1% isoflurane （6.13%±1.56%, P〈0.01） and ERK1/2 activities. Conclusions Isoflurane is capable of inducing preconditioning in hippocampal slices in vitro in a dose-dependent manner, and dual exposure to isoflurane with a lower concentration is more effective in triggering preconditioning than a single exposure. Isoflurane-induced neuroprotection might be involved with ERK 1/2 activities.

Cobra phospholipase A2 protect cerebellar granule neurons from apoptosis with mechanism independent of enzymatic activity

A fraction of cobra （Naja naja atra） venom has been discovered to have protective effect on rat cultural cerebellar granule neurons （CGNs） from apoptosis induced by removing serum and reducing the extracellular potassium concentration from 25 to 5 mM. This component has been purified and identified as secreted phospholipase A2 （cobra sPLA2）. In order to study the relationship between the protection on CGNs and enzymatic activity of phospholipase A2, CGNs stained by Hoechst 33258 were quantified to determine survival rate under the fluorescence microscopy; the protective potencies on apoptosis of cultural CGNs were compared among cobra sPLA2, the cobra sPLA2 modified in carboxylate groups with water soluble carbodiimide and semicarbazide, and the heated cobra sPLA2 at 80℃ for 30 rain. The results showed that the CGN survival rate was unaffected significantly both in modified cobra sPLAz whose enzymatic activity of PLA2 had decreased by 80%, and in cobra sPLA2 adding 7, 7-Dimethyleicosadienoic acid, an inhibitor of sPLA2 at concentration of 10-fold IC50; contrary, the neuronal survival rate fell about 60% in heated cobra sPLA2, although its PLA2 activity only decreased by 10%. The protection on CGNs were also found in some of sPLA2s derived from venoms of bee, Naja naja mossambica, Crotalus atroxalso and Vipera Ammodytes Ammodytes but could not be found in other sPLA2s from bovine pancreas and Streptomyces violaceoruber. Above results suggest that the protection on CGNs of cobra sPLA2 is independent of its enzymatic activity.

Cardiac Remote Conditioning and Clinical Relevance:All Together Now!

Acute myocardial infarction （AMI） is the leading cause of death and disability worldwide. Timely reperfusion is the standard of care and results in decreased infarct size, improving patient survival and prognosis. However, 25% of patients proceed to develop heart failure （HF） after myocardial infarction （MI） and 50% of these will die within five years. Since the size of the infarct is the major predictor of the outcome, including the development of HF, therapies to improve myocardial salvage have great potential. Over the past three decades, a number of stimuli have been discovered that activate endogenous cardioprotective pathways. In ischemic preconditioning （IPC） and ischemic postconditioning, ischemia within the heart initiates the protection. Brief reversible episodes of ischemia in vascular beds remote from the heart can also trigger cardioprotection when applied before, during, or immediately after myocardial ischemia-- known as remote ischemic pre-, per-, and post-conditioning, respectively. Although the mechanism of remote ischemic preconditioning （RIPC） has not yet been fully elucidated, many mechanistic components are shared with IPC. The discovery of RIPC led to research into the use of remote non-ischemic stimuli including nerve stimulation （spinal and vagal）, and electroacupuncture （EA）. We discovered and, with others, have elucidated mechanistic aspects of a non- ischemic phenomenon we termed remote preconditioning of trauma （RPCT）. RPCT operates via neural stimulation of skin sensory nerves and has similarities and differences to nerve stimulation and EA conducted at acupoints. We show herein that RPCT can be mimicked using electrical stimulation of the abdominal midline （EA-like treatment） and that this modality of activating cardioprotection is powerful as both a preconditioning and a postconditioning stimulus （when applied at reperfusion）. Investigations of these cardioprotective phenomena have led to a more integrative understanding of mechanisms related to cardioprotection, and in the last five to ten years, it has become clear that the mechanisms are similar, whether induced by ischemic or non-ischemic stimuli. Taking together much of the data in the literature, we propose that all of these cardioprotective ＂conditioning＂ phenomena represent activation from different entry points of a cardiac conditioning network that converges upon specific mediators and effectors of myocardial cell survival, including NF-KB, Stat3/5, protein kinase C, bradykinin, and the mitoKA^P channel. Nervous system pathways may represent a novel mechanism for initiating conditioning of the heart and other organs. IPC and RIPC have proven difficult to translate clinically, as they have associated risks and cannot be used in some patients. Because of this, the use of neural and nociceptive stimuli is emerging as a potential non-ischemic and non-traumatic means to initiate cardiac conditioning. Clinical relevance is underscored by the demonstration of postconditioning with one of these modalities, supporting the conclusion that the development of pharmaceuticals and electroceuticals for this purpose is an area ripe for clinical development.

Scutellaria baicalensis, the golden herb from the garden of Chinese medicinal plants

Scutellaria baicalensis Georgi, or Chinese skullcap, has been widely used as a medicinal plant in China for thousands of years, where the preparation from its roots is called Huang-Qin. It has been applied in the treatment of diarrhea, dysentery, hypertension, hemorrhaging, insomnia,inflammation and respiratory infections. Flavones such as baicalin, wogonoside and their aglycones baicalein wogonin are the major bioactive compounds extracted from the root of S. baicalensis. These flavones have been reported to have various pharmacological functions, including anti-cancer,hepatoprotection, antibacterial and antiviral, antioxidant,anticonvulsant and neuroprotective effects. In this review,we focus on clinical applications and the pharmacological properties of the medicinal plant and the flavones extracted from it. We also describe biotechnological and metabolic methods that have been used to elucidate the biosynthetic pathways of the bioactive compounds in Scutellaria.

The herbal compound geniposide rescues formaldehyde-induced apoptosis in N2a neuroblastoma cells

The herbal medicine Tong Luo Jiu Nao （TLJN） contains geniposide （GP） and ginsenoside Rgl at a molar ratio of i0：1. Rgl is the major component of another herbal medicine, panax notoginseng saponin （PNS）. TLJN has been shown to strengthen brain function in humans, and in animals it improves learning and memory. We have previously shown that TLJN reduces amyloi- dogenic processing in Alzheimer＇s disease （AD） mouse models. Together this suggests TLJN may be a potential treatment for patients with dementia. Because chronic damage of the central nervous system by formaldehyde （FA） has been presented as a risk factor for age-associated cognitive dysfunction, in the present study we investigated the protective effect of both TLJN and GP in neuron-like cells exposed to FA. FA-exposed murine N2a neuroblastoma cells were incubated with TLJN, its main in- gredient GP, as well as PNS, to measure cell viability and morphology, the rate of apoptosis and expression of genes encoding Akt, FOXO3, Bcl2 and p53. The CCK-8 assay, cytoskeletal staining and flow cytometry were used to test cell viability, mor- phology and apoptosis, respectively. Fluorescent quantitative real-time PCR （qRT-PCR） was used to monitor changes in gene expression, and HPLC to determine the rate of FA clearance. Treatment of N2a cells with 0.09 mmol L-1 FA for 24 h signifi- cantly reduced cell viability, changed cell morphology and promoted apoptosis. Both TLJN and GP conferred neuroprotection to FA-treated N2a cells, whereas PNS, which had to be used at lower concentrations because of its toxicity, did not. Our data demonstrate that TLJN can rescue neuronal damage caused by FA and that its main ingredient, GP, has a major role in this ef- ficacy. This presents purified GP as a drug or lead compound for the treatment of AD.

microRNA-21a-5p/PDCD4 axis regulates mesenchymal stem cell-induced neuroprotection in acute glaucoma

Mesenchymal stem ceils （MSCs） have been demonstrated to have promising therapeutic benefits for a variety of neurological dis- eases; however, the underlying mechanisms are poorly understood. Here, we showed that intravitreal infusion of MSCs promoted retinal ganglion cell （RGC） survival in a mouse model of acute glaucoma, with significant inhibition of microglial activation, production of TNF-α, IL-1β, and reactive oxygen species, as well as caspase-8 and caspase-3 activation. In vitro, MSCs inhibited both caspase-8-mediated RGC apoptosis and microgUal activation, partly via the action of stanniocalcin 1 （STCl）. Furthermore, we found that microRNA-21a-Sp （miR-21） and its target, PDCD4, were essential for STC1 production and the neuroprotective property of MSCs in vitro and in vivo. Importantly, miR-21 overexpression or PDCD4 knockdown augmented MSC-mediated neuroprotective effects on acute glaucoma. These data highlight a previously unrecognized neuroprotective mechanism by which the miR-21/ PDCD4 axis induces MSCs to secrete STC1 and other factors that exert neuroprotective effects. Therefore, modulating the miR- 21/PDCD4 axis might be a promising strategy for clinical treatment of acute glaucoma and other neurological diseases.

Effect of glycyrrhizin on traumatic brain injury in rats and its mechanism

Objective： To investigate the neuropro- tective effects of glycyrrhizin （Gly） as well as its effect on expression of high-mobility group box 1 （HMGB1） in rats after traumatic brain injury （TBI）. Methods： Male Sprague-Dawley rats were randomly divided into three groups： sham group, TBI group, and TBI＋Gly group （n=36 per group）. Rat TBI model was made by using the modified Feeney＇s method. In TBI＋Gly group, Gly was administered intravenously at a dosage of l0 mg/kg 30 min after TBI. At 24 h after TBI, motor function and brain water content were evaluated. Meanwhile, HMGB 1/HMGB 1 receptors including toll-like receptor 4 （TLR4） and receptor for advanced glycation end products （RAGE）/nuclear fac- tor-κ B（NF- κ B） signaling pathway and inflammatory cytokines in the injured brain tissues were detected using quantitative real-time polymerase chain reaction, western blot, electrophoretic mobility shift assay and enzyme-linked immunosorbent assay. Furthermore, HMGB l, RAGE and TLR4 immunohistochemistry and apoptosis were analyzed. Results： Beam walking performance impairment and brain edema were significantly reduced in TBI＋Gly group compared with TBI group; meanwhile, the over-expressions of HMGB 1PHMGB 1 receptors （TLR4 and RAGE）/NF- κB DNA-binding activity and inflammatory cytokines were inhibited. The percentages of HMGB 1, RAGE and TLR4- positive cells and apoptotic cells were respectively 58.37%±5.06%, 54.15%±4.65%, 65.50%± 4.83%, 52.02%±4.63% in TBI group and 39.99%±4.99%, 34.87%±5.02%, 43.33%±4.54%, 37.84%±5.16% in TBI＋Gly group （all P〈0.01 compared with TBI group）. Conclusion： Gly can reduce secondary brain injury and improve outcomes in rat following TBI by down-regula- tion of HMGB 1/HMGB 1 receptors （TLR4 and RAGE）/NF- κB - mediated inflammatory responses in the injured rat brain.

Neuroprotective effects of Fructus Chebulae extracts on experimental models of cerebral ischemia

OBJECTIVE:To investigate the neuroprotective effects of Fructus Chebulae extract using both in vivo and invitromodels of cerebral ischemia.METHODS:As an in vitro model,oxygen glucose deprivation followed by reoxygenation(OGD-R)and hydrogen peroxide(H2O2)induced cellular damage in rat pheochromocytoma(PC12)cells was used to investigate the neuroprotective effects of extract of Fructus Chebulae.3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to calculate cell survival.For in vivo,occlusion of left middle cerebral artery on rats was carried out as a focal cerebral ischemic model.RESULTS:Fructus Chebulae extract increases the PC12 cell survival against OGD-R and H2O2by 68%and 91.4%respectively.Fructus Chebulae also de-creases the cerebral infarct volume by 39%and extent of hemisphere swelling from 17%in control group to 10%in FructusChebulaetreated group.CONCLUSION:Fructus Chebulae,as a traditional medicine,can rescue the neuronal cell death against ischemia related damage.The possible mechanism for the neuroprotection might be the inhibition of oxidative damages occurring after acute phase of cerebral ischemia.

Neuroprotective effect of Naomaitong extract following focal cerebral ischemia induced by middle cerebral artery occlusion in rats

OBJECTIVE: To examine the neuroprotective effect of extract from Naomaitong following focal cerebral ischemia reperfusion induced by occlusion of middle cerebral artery(MCA), and to determine the biochemical alterations in urine using proton nuclear magnetic resonance spectroscopy and principal component analysis.METHODS: Wistar rats were randomly assigned tothree groups: sham-operated group, MCA focal cerebral ischemia reperfusion model group, and active extract of Naomaitong treatment group. The model was established by an improved MCA occlusion(MCAO) method. Sham-operated rats received the same surgical procedure, but without occlusion. The Naomaitong treatment group were treated with active extract from Naomaitong at a dose of3.0 g·kg-·1d-1. Brain tissues and urine samples were collected from all groups for histopathological assessment and proton nuclear magnetic resonance spectroscopy-based metabonomics, respectively.RESULTS: Hematoxylin-eosin and triphenyl tetrazolium chloride staining of brain tissues showed a significant decrease in cerebral infarction area in the Naomaitong group. In model rats, metabonomic analyses showed increased urinary levels of glutamate, taurine, trimetlylamine oxide, betaine, and glycine, and reduced levels of creatinine and creatine.Naomaitong regulated the metabolic changes by acting on multiple metabolic pathways, including glycine metabolism, glutaminolysis, transmethylation metabolism and creatinine metabolism.CONCLUSION: These data demonstrate that extract from Naomaitong is neuroprotective against focal cerebral ischemia induced by MCAO, and can alleviate biochemical changes in urinary metabolism. Metabonomics may be a useful approach for assessing the biochemical mechanisms underlying the neuroprotective actions of extract from Naomaitong.

Protective effect of astrocyte-conditioned medium on neurons following hypoxia and mechanical injury

Objective： To investigate the protective effect of mouse astrocyte-conditioned medium （ACM） on hypoxic and mechanically injured neurons by a cell model in vitro, and to explore the possible mechanism. Methods： The model of hypoxic neuronal injury was caused by 3% 02 in three-gas incubator. Neurons were cultured with ordinary medium or 20% ACM respectively and randomly divided into hypoxic group （hypoxia for 4, 8, 24 h and marked as H4R0, H8R0, H24R0） and hypoxia reoxygenation group （H4R24, H8R24, H24R24）. Mechanical injury model was developed by scratching neurons cultured in 20% ACM or ordinary medium to different degrees. Neu- rons in both medium were divided into normal control group, mild, moderate and severe injury groups. The 20% ACM was added 24 h before hypoxia/reoxygenation or mechanical injury. The morphology and survival of neurons were observed and counted by trypan blue staining. The concentration of NO, lactic dehydrogenase （LDH） and membrane ATPase activity were detected by corresponding kits. Results： It was showed that 20% ACM can obviously promote the survival rate of hypoxia/reoxygenated neurons and scratched neurons as well. The morphology and num- ber of neurons exposed to hypoxia or scratch injury showed great difference between groups with or without ACM treatment. Compared with control group, the concentration of NO and LDH was much lower in hypoxic/reoxygenated neurons treated with 20% ACM, and the ATPase activity was higher. For the mechanical injury model, neurons with moderate injury also revealed a lower NO and LDH concen- tration than the control group. All the differences were sta- tistically significant （P〈0.05）. Conclusion： ACM can promote the survival and func- tional recovery of neurons following hypoxia or scratching to a certain degree. The mechanism may be associated with reducing the synthesis and release of NO and LDH as well as increasing the activity of membrane ATPase.

Effects of nerve growth factor on neuronal nitric oxide production after spinal cord injury in rats

Objective: To explore the protective effects of nerve growth factor (NGF) on injured spinal cord. Methods: The spinal cord injury (SCI) model of Wistar rats was established by a 10 g× 2.5 cm impact force on the T 8 spinal cord. NGF (60 μg/20 μl) was given to the rats of the treatment group immediately and at 2, 4, 8, 12, 24 hours after SCI. The level of neuronal constitutive nitric oxide synthase (ncNOS) and the expression of ncNOS mRNA in the spinal cord were detected by the immunohistochemistry assay and in situ hybridization method. Results: Abnormal expression of ncNOS was detected in the spinal ventral horn motorneuron in injured rats. The levels of ncNOS protein in the NGF group were significantly lower than those in the normal saline group (P< 0.05 ). The ncNOS mRNA expression was found in the spinal ventral horn motorneuron in injured rats and the expression in the NGF group was significantly decreased compared with that in the normal saline group (P< 0.01 ). Conclusions: NGF can protect the injured tissue of the spinal cord by prohibiting abnormal expression of nitric oxide synthase and the neurotoxicity of nitric oxide.