Characteristics of Visual Evoked Potential in Different Parts of Visual Impairment. / 不同部位损伤致视力障碍的视觉诱发电位特征.

OBJECTIVES: To study the quantitative and qualitative differences of visual evoked potential (VEP) in monocular visual impairment after different parts of visual pathway injury. METHODS: A total of 91 subjects with monocular visual impairment caused by trauma were selected and divided into intraocular refractive media-injury group (eyeball injury group for short), optic nerve injury group, central nervous system injury and intracranial combined injury group according to the injury cause and anatomical segment. Pattern Reversal visual evoked potential (PR-VEP) P100 peak time and amplitude, Flash visual evoked potential (F-VEP) P2 peak time and amplitude were recorded respectively. SPSS 26.0 software was used to analyze the differences of quantitative (peak time and amplitude) and qualitative indexes (spatial frequency sweep-VEP acuity threshold, and abnormal waveform category and frequency) of the four groups. RESULTS: Compared with healthy eyes, the PR-VEP P100 waveforms of the intraocular eyeball injury group and the F-VEP P2 waveforms of the optic nerve group showed significant differences in prolonged peak time and decreased amplitude in injured eyes (P<0.05). The PR-VEP amplitudes of healthy eyes were lower than those of injured eyes at multiple spatial frequencies in central nervous system injury group and intracranial combined injury group (P<0.05).The amplitude of PR-VEP in patients with visual impairment involving central injury was lower than that in patients with eye injury at multiple spatial frequencies. The frequency of VEP P waveforms reaching the threshold of the intraocular injury group and the optic nerve injury group were siginificantly different from the intracranial combined injury group, respectively(P<0.008 3), and the frequency of abnormal reduction of VEP amplitude of threshold were significantly different from the central nervous system injury group, respectively(P<0.008 3). CONCLUSIONS: VEP can distinguish central injury from peripheral injury, eyeball injury from nerve injury in peripheral injury, but cannot distinguish simple intracranial injury from complex injury, which provides basic data and basis for further research on the location of visual impairment injury.

Salubrinal offers neuroprotection through suppressing endoplasmic reticulum stress, autophagy and apoptosis in a mouse traumatic brain injury model.

Traumatic brain injury (TBI) is a complex injury that can cause severe disabilities and even death. TBI can induce secondary injury cascades, including but not limited to endoplasmic reticulum (ER) stress, apoptosis and autophagy. Although the investigators has previously shown that salubrinal, the selective phosphatase inhibitor of p-eIF2α, ameliorated neurologic deficits in murine TBI model, the neuroprotective mechanisms of salubrinal need further research to warrant the preclinical value. This study was undertaken to characterize the effects of salubrinal on cell death and neurological outcomes following TBI in mice and the potential mechanisms. In the current study, ER stress-related proteins including p-eIF2α, GRP78 and CHOP showed peak expressions both in the cortex and hippocampus from day 2 to day 3 after TBI, indicating ER stress was activated in our TBI model. Immunofluorescence staining showed that CHOP co-located NeuN-positive neuron, GFAP-positive astrocyte, Iba-1-positive microglia, CD31-positive vascular endothelial cell and PDGFR-ß-positive pericyte in the cortex on day 2 after TBI, and these cells mentioned above constitute the neurovascular unit (NVU). We also found TBI-induced plasmalemma permeability, motor dysfunction, spatial learning and memory deficits and brain lesion volume were alleviated by continuous intraperitoneal administration of salubrinal post TBI. To investigate the underlying mechanisms further, we determined that salubrinal suppressed the expression of ER stress, autophagy and apoptosis related proteins on day 2 after TBI. In addition, salubrinal administration decreased the number of CHOP+/TUNEL+ and CHOP+/LC3+ cells on day 2 after TBI, detected by immunofluorescence. In conclusion, these data imply that salubrinal treatment improves morphological and functional outcomes caused by TBI in mice and these neuroprotective effects may be associated with inhibiting apoptosis, at least in part by suppressing ER stress-autophagy pathway.

Caspr Controls the Temporal Specification of Neural Progenitor Cells through Notch Signaling in the Developing Mouse Cerebral Cortex.

The generation of layer-specific neurons and astrocytes by radial glial cells during development of the cerebral cortex follows a precise temporal sequence, which is regulated by intrinsic and extrinsic factors. The molecular mechanisms controlling the timely generation of layer-specific neurons and astrocytes remain not fully understood. In this study, we show that the adhesion molecule contactin-associated protein (Caspr), which is involved in the maintenance of the polarized domains of myelinated axons, is essential for the timing of generation of neurons and astrocytes in the developing mouse cerebral cortex. Caspr is expressed by radial glial cells, which are neural progenitor cells that generate both neurons and astrocytes. Absence of Caspr in neural progenitor cells delays the production cortical neurons and induces precocious formation of cortical astrocytes, without affecting the numbers of progenitor cells. At the molecular level, Caspr cooperates with the intracellular domain of Notch to repress transcription of the Notch effector Hes1. Suppression of Notch signaling via a Hes1 shRNA rescues the abnormal neurogenesis and astrogenesis in Caspr-deficient mice. These findings establish Caspr as a novel key regulator that controls the temporal specification of cell fate in radial glial cells of the developing cerebral cortex through Notch signaling.

[Research Progress of Event-related Potential in Mild Cognitive Impairment].

Mild cognitive impairment caused by craniocerebral trauma is the key points and difficulties in judicial authentication. This article has comparative analysis of each mode of event-related potential (classical Oddball, Eriksen flanker task and so on), which can provide a more objective method for such craniocerebral trauma cases in clinical forensic judicial authentication.

[Correlation of daily living activities with location and severity of traumatic brain injury].

OBJECTIVE: To study the correlation of daily living activities with location and severity of trau- matic brain injury (TBI) and to provide a theoretical basis for improving the accuracy of expert opinion. METHODS: Five hundred and one cases of patients with TBI were selected. Detailed records included following: pre-injury situation, location and severity of injury, treatment and education. Daily living activi- ties scale (Barthel index) was applied to test the subjects' daily living activities. The relevance among location and severity of TBI and Barthel index was statistically analyzed. RESULTS: In mild TBI group, there was no significant difference in Barthel index among each location (P>0.05). In moderate TBI group, there were significant differences in Barthel index between subarachnoid hemorrhage and cerebral lobe injury, also between parietal, occipital lobes injury and frontal lobe injury, parietal, occipital lobes injury and temporal lobe (P<0.05), respectively, whereas no significant difference in Barthel index between frontal lobe injury and temporal lobe injury (P>0.05). In severe TBI, there were significant differences in Barthel index between every two different locations (P<0.05). CONCLUSION: There is some correlation between the location of TBI and Barthel index, which provides an important reference value for analyzing and determining daily living activities after TBI.

Therapeutic effect of SN50, an inhibitor of nuclear factor-κB, in treatment of TBI in mice.

NF-κB upregulation has been demonstrated in neurons and glial cells in response to experimental injury and neuropathological disorders, where it has been related to both neurodegenerative and neuroprotective activities. It has been generally recognized that NF-κB plays important roles in the regulation of apoptosis and inflammation as well as innate and adaptive immunity. However, the regulatory mechanism of NF-κB in apoptosis remained to be determined. The present study sought to first investigate the effect of a NF-κB inhibitor SN50, which inhibits NF-κB nuclear translocation, on cell death and behavioral deficits in our mice traumatic brain injury (TBI) models. Additionally, we tried to elucidate the possible mechanisms of the therapeutic effect of SN50 through NF-κB regulating apoptotic and inflammatory pathway in vivo. Encouragingly, the results showed that pretreatment with SN50 remarkably attenuated TBI-induced cell death (detected by PI labeling), cumulative loss of cells (detected by lesion volume), and motor and cognitive dysfunction (detected by motor test and Morris water maze). To analyze the mechanism of SN50 on cell apoptotic and inflammatory signaling pathway, we thus assessed expression levels of TNF-α, cathepsin B and caspase-3, Bid cleavage and cytochrome c release in SN50-pretreated groups compared with those in saline vehicle groups. The results imply that through NF-κB/TNF-α/cathepsin networks SN50 may contribute to TBI-induced extrinsic and intrinsic apoptosis, and inflammatory pathways, which partly determined the fate of injured cells in our TBI model.

Necrostatin-1 suppresses autophagy and apoptosis in mice traumatic brain injury model.

Traumatic brain injury (TBI) results in neuronal apoptosis, autophagic cell death and necroptosis. Necroptosis is a newly discovered caspases-independent programmed necrosis pathway which can be triggered by activation of death receptor. Previous works identified that necrostatin-1 (NEC-1), a specific necroptosis inhibitor, could reduce tissue damage and functional impairment through inhibiting of necroptosis process following TBI. However, the role of NEC-1 on apoptosis and autophagy after TBI is still not very clear. In this study, the amount of TBI-induced neural cell deaths were counted by PI labeling method as previously described. The expression of autophagic pathway associated proteins (Beclin-1, LC3-II, and P62) and apoptotic pathway associated proteins (Bcl-2 and caspase-3) were also respectively assessed by immunoblotting. The data showed that mice pretreated with NEC-1 reduced the amount of PI-positive cells from 12 to 48 h after TBI. Immunoblotting results showed that NEC-1 suppressed TBI-induced Beclin-1 and LC3-II activation which maintained p62 at high level. NEC-1 pretreatment also reversed TBI-induced Bcl-2 expression and caspase-3 activation, as well as the ratio of Beclin-1/Bcl-2. Both 3-MA and NEC-1 suppressed TBI-induced caspase-3 activation and LC3-II formation, Z-VAD only inhibited caspase-3 activation but increased LC3-II expression at 24 h post-TBI. All these results revealed that multiple cell death pathways participated in the development of TBI, and NEC-1 inhibited apoptosis and autophagy simultaneously. These coactions may further explain how can NEC-1 reduce TBI-induced tissue damage and functional deficits and reflect the interrelationship among necrosis, apoptosis and autophagy.

Poloxamer-188 attenuates TBI-induced blood-brain barrier damage leading to decreased brain edema and reduced cellular death.

Plasmalemma permeability plays an important role in the secondary neuronal death induced by traumatic brain injury (TBI). Previous works showed that Poloxamer 188 (P188) could restore the intactness of the plasma membrane and play a cytoprotective action. However, the roles of P188 in blood-brain barrier (BBB) integrity and TBI-induced neural cell death are still not clear. In this study, mice were induced TBI by controlled cortical impact (CCI), and cerebral water content was measured to explore the profile of brain edema after CCI. Further, the regimen of P188 in mouse CCI models was optimized. The neurological test and BBB integrity assessment were performed, and the numbers of TBI-induced neural cell death were counted by propidium iodide (PI) labeling. The expression of apoptotic pathway associated proteins (Bax, cyt-c, caspase-8, caspase-9, caspase-3, P53) and aquaporin-4 (AQP4) was assessed by RT-PCR or immunoblotting. The data showed that the brain edema peaked at 24 h after TBI in untreated animals. Tail intravenous injection of P188 (4 mg/ml, 100 µl) 30 min before TBI or within 30 min after TBI could attenuate TBI-induced brain edema. P188 pre-treatment restored BBB integrity, suppressed TBI-induced neural cell death, and improved neurological function. TBI induced an up-regulation of Bax, cyt-c, caspase-8, caspase-9, caspase-3, and the expression of p53 was down-regulated by P188 pre-treatment. AQP4 mainly located on endothelial cells and astrocytes, and its expression was also regulated by P188 pretreatment. All these results revealed that P188 attenuates TBI-induced brain edema by resealing BBB and regulating AQP4 expression, and suppressed apoptosis through extrinsic or intrinsic pathway. Plasmalemma permeability may be a potential target for TBI treatment.

[Characteristics and distribution of ERP by different field stimulation].

OBJECTIVE: To study the variation of latency and amplitude of the event related potential (ERP) and its distribution in human scalp when the normal subjects were stimulated with different visual fields. METHODS: The ERP recorded in scalp with the stimulation of 10 degrees visual field and 60 degrees visual field respectively in 20 healthy volunteers with normal visual function. RESULTS: Two different visual field stimulation may evoke the different exogenous components P1 (70-125 ms), N1 (90-170 ms), P2 (140-220 ms) and endogenous components N2 (190-280 ms) and P3 (290-430 ms). The latencies of all the components evoked by 10 degrees visual field were shorter than that of the 60 degrees visual field while the amplitudes of N1 and N2 were lower and appeared over the extensive encephalic region; and the amplitudes of the P1, P2 and P3 were higher and appeared in occipitotemporal, prefrontal and occipital region, respectively. CONCLUSION: Two different visual field stimulation may evoke all the ERP components with significant differences in the latency, amplitude and distribution. The differences may reflect the different visual information integration and processing in human brain during the different visual field stimulation.

[Correlation of pattern reversal visual evoked potentials P100 with visual acuity].

OBJECTIVE: To explore pattern reversal visual evoked potential (PRVEP) P100 components in the patients with different visual acuity and the correlation of P100 components with visual acuity using different visual simulation angles. METHODS: PRVEPs were recorded at Oz point in the patients (100 eyes) with different visual acuity including 0.2, 0.4, 0.6, 0.8 and 1.0 and induced by pattern reversal visual simulation with the different spatial frequencies(check sizes: 8 degrees-7.5'). The latency and amplitude of components P100 were analyzed and statistical analysis was performed using SPSS 13.0 software. RESULTS: The latency and amplitude of P100 wave showed a curvilinear relationship with check sizes. With check size 10 simulation in 0.2 visual acuity group, the P100 latency reached to the minimum and the P100 amplitude showed peak value. Other groups displayed the best value with check size 30'. The P100 latency and amplitude showed a linear correlation with visual acuity. With the increase of visual acuity, the P100 wave latency decreased and the amplitude increased gradually. Regression models between visual acuity and the Pic wave latency and amplitude were also established. CONCLUSION: The regression functions can be an objective and accurate method to evaluate the visual acuity based on the better simulation angles using PRVEP examination.

Cathepsin B contributes to traumatic brain injury-induced cell death through a mitochondria-mediated apoptotic pathway.

It has been reported that lysosomal proteases play important roles in ischemic and excitotoxic neuronal cell death. We have previously reported that cathepsin B expression increased remarkably after traumatic brain injury (TBI). The present study sought to investigate the effects of a selective cathepsin B inhibitor (CBI) [N-L-3-trans-prolcarbamoyloxirane-2-carbonyl)-L-isoleucyl-L-proline] on cell death and behavioral deficits in our model. We examined the levels of cathepsin B enzymatic activity and its expression by double labelling damaged cells in the brain slice with propidium iodide (PI) and anticathepsin B. The results showed an elevated enzymatic activity associated with TBI-induced increase in a mature form of cathepsin B, suggesting that cathepsin B may play a role in TBI-induced cell injury. PI was found to label cells positive for the neuronal-specific nuclear marker NeuN, whereas fewer GFAP-positive cells were labelled by PI, suggesting that neurons are more sensitive to cell death induced by TBI. Additionally, we found that pretreatment with CBI remarkably attenuated TBI-induced cell death, lesion volume, and motor and cognitive dysfunction. To analyze the mechanism of action of cathepsin B in the cell death signaling pathway, we assessed DNA fragmentation by electrophoresis, Bcl-2/Bax protein expression levels, Bid cleavage, cytochrome c release, and caspase-3 activation. The results imply that cathepsin B contributes to TBI-induced cell death through the present programmed cell necrosis and mitochondria-mediated apoptotic pathways.

[The expression and significance of nerve growth factor and its receptors in pancreatic ductal adenocarcinoma].

OBJECTIVE: To investigate nerve growth factor (beta-NGF) and its receptors expression in human pancreatic ductal adenocarcinoma. METHODS: Expression and distribution of beta-NGF, tyrosine kinase A (TrKA) and P75(NGFR) were detected in operation tissue specimens of pancreatic ductal adenocarcinoma with immunohistochemistry and real-time PCR. Relations of beta-NGF and its receptors with clinical pathological characters, especially nerve invasion were analyzed. RESULTS: beta-NGF and TrKA expression are higher in pancreatic adenocarcinoma than normal pancreas, and the differences are significant (P < 0.01). beta-NGF and TrKA expression are associated with the differentiation grades (DG), lymphatic node metastasis, nerve invasion and surgical pathological stages. Poorer of DG and later stages, more expression of beta-NGF and TrKA. beta-NGF and TrKA expression have positive correlations. beta-NGF, TrKA and P75(NGFR) mRNA expression have significantly increased 3.84, 4.23 and 2.41 times than normal tissues by real-time PCR, respectively. CONCLUSIONS: beta-NGF and TrKA might play potential roles in carcinogenesis for pancreatic cancer, have affinity with clinicopathological characters of pancreatic cancer. beta-NGF and TrKA may have mutual effect in signal transduction leading to perineural invasion of pancreatic carcinoma.

[The progress in the study of visual field in spatial attention by event related potentials].

Event-related potentials (ERP) is a good temporal resolution method to study the mechanism of visual field in brain. With the development of technique of high-density recording and brain imaging, the ERP is widely used in the location of the brain function. This article reviews the methods, results and primary conclusions in the field, and suggests several perspectives for the future research and application of ERP in the forensic science.

[Effects of Jinmaitong capsule on nerve growth factor in diabetic rats].

OBJECTIVE: To study the effects of Jinmaitong Capsule (JMT) on the expression of NGF and NGF mRNA in STZ-induced diabetic rats. METHOD: Fifty SZT-induced diabetic rats were randomly divided into 5 groups including model group, low-dose JMT group (treated with JMT similar to the quintupling dose of adult recommended dosage), middle-dose JMT group (treated with JMT similar to the decuple dose of adult recommended dosage), high-dose JMT group (treated with JMT similar to the twenty-fold dose of adult recommended dosage) and Neurotropin group (treated with Neurotropin similar to the decuple dose of adult recommended dosage). Ten normal rats matching with weight and age served as normal control group. All rats were given intragastric administration for 16 weeks and then killed. Body weight and blood glucose were detected before and at the 4, 8, 12, 16th week after treatment. The hydrothermal tail-flick and pain threshold to mechanical stimulation with Von Frey filament were carried out before death. The expression of NGF and NGF-mRNA in sciatic nerve were detected by SABC immunohistochemical method and real-time fluorogenetic quantitative PCR respectively. RESULT: The blood glucose levels of STZ-DM rats were much higher than those of normal rats (P < 0.01). In all the treated groups, there were no significant differences among them compared each other or compared with model group. And it got the same result when concerning about body weight no matter how the rats were dealt with. Hydrothermal tail-flick test: The tail-flick latency of STZ-DM rats were much longer than those of normal rats (P < 0.01 or P < 0.05). Compared with model group, the time shortened significantly in low, middle-dose of JMT groups and Neutrophin group. Compared with normal group, the pain thresholds of model group decreased extremely (P < 0.01). Compared with model group, the threshold values of low-dose, middle-dose JMT group and neutrophin group raised strikingly (P < 0.05). The levels of NGF-mRNA expression in STZ-DM rats were much lower than those of the normal rats (P < 0.01). Compared with model group, NGF-mRNA expression of middle-dose JMT group and Neurotropin group upregulated noticeably (P < 0.01). The integrated option density of NGF expression in STZ-DM rats was much lower than the normal (P < 0.01 or P < 0.05). And the levels of NGF in all the treated groups increased notably compared with model group (P < 0.05 or P < 0.01). There were no significant differences among middle-dose JMT group and Neutrophin group. CONCLUSION: Traditional Chinese medicine JMT could up-regulate the expression of NGF and NGF-mRNA in sciatic nerve.

Point mutation at single tyrosine residue of novel oncogene NOK abrogates tumorigenesis in nude mice.

Receptor protein-tyrosine kinases (RPTKs) are tightly regulated during normal cellular processes including cell growth, differentiation, and metabolism. Recently, a RPTK-like molecule named novel oncogene with kinase-domain (NOK) has been cloned and characterized. Overexpression of NOK caused severe cellular transformation as well as tumorigenesis and metastasis in nude mice. In the current study, we generated two tyrosine-->phenylalanine (Y-->F) point mutations (Y327F and Y356F) within the endodomain of NOK that are well conserved in many RPTK subfamilies and are the potential tyrosine phosphorylation sites important for major intracellular signaling. Using BaF3 cells stably expressing the ectodomain of mouse erythropoietin receptor, and the transmembrane and endodomain of NOK (BaF3-E/N), we were able to show that point mutations at either Y327 or Y356 dramatically blocked cellular transformation by NOK as examined by colony formation and cellular DNA synthesis. In addition, tumorigenesis induced by BaF3-E/N was completely abrogated upon the introduction of either single mutation. Importantly, signaling studies revealed that the activation of extracellular signal-regulated kinase was inhibited by Y356F and was significantly reduced by Y327F. Both mutations significantly impaired Akt phosphorylation. Interestingly, both mutations did not affect the kinase activity of NOK. Moreover, apoptotic analysis revealed that both mutations accelerated cell death by activating caspase-3-mediated pathways. Thus, our study shows that these potential tyrosine phosphorylation sites may play critical roles in NOK-mediated tumorigenesis both in vitro and in vivo.

IN VIVO EFFECT OF GUIDING-HERB RADIX PLATYCODONIS AND RADIX CYATHULAE ON PAEONIFLORIN PHARMACOKINETICS OF XUEFU ZHUYU TANG IN RATS.

BACKGROUND: Xuefu Zhuyu Tang (XFZYT), first recorded in Correction of Errors in Medical Works by Qing-ren Wang, has been proven reliable and effective for curing various diseases such as atherosclerosis, hypertension, hyperlipidemia, and angina pectoris. It consists of 11 herbs and two of them, Radix platycodonis and Radix cyathulae, have been traditionally considered as guiding herbs and deeply valued by tens of millions of Chinese medicine practitioners. Do Radix platycodonis and Radix cyathulae affect the pharmacokinetics of the effective constituent-paeoniflorin of XFZYT? If yes, in what way? This study aims to answer these questions. MATERIALS AND METHODS: The medicinal solutions of XFZYT, XFZYT without Radix platycodonis (XFZYT-JG), XFZYT without Radix cyathulae (XFZYT-NX), and XFZYT without Radix platycodonis and Radix cyathulae (XFZYT-JG-NX) were prepared and administrated to rats in the normal group and the blood-stasis model group by gavage, respectively. The blood samples of rats in the normal group were obtained 5, 10, 15, 20, 30, 45, 60, 120, and 240 minutes after gavage; whereas the blood samples of rats in the blood-stasis model group were obtained 10, 15, 20, 30, 45, 90, 150, and 240 minutes after gavage. Biological samples were processed; the assays of specificity, precision, linearity, intra-day and inter-day precisions, recovery and stability were conducted; high performance liquid chromatography was performed to detect paeoniflorin content; and DAS software was adopted to generate pharmacokinetic parameters. Mobile phase was composed of acetonitrile and water (16:84), detection wavelength was 230 nm, and riboflavin was set as internal standard substance. RESULTS: The pharmacokinetic parameters of the rats in the normal group after oral gavage of XFZYT, XFZYT-JG, XFZYT-NX, and XFZYT-JG-NX were Cmax = (0.363±0.248, 0.065±0.020, 0.099±0.033, 0.099±0.020) mg/L, Tmax = (0.276±0.084, 0.583±0.342, 0.555±0.228, 0.317±0.033)h, t1/2 = (0.501±0.241, 1.021±0.522, 0.853±0.377, 1.227±0.402) h; and AUC0-∞ = (0.381±0.415, 0.13±0.085, 0.166±0.066, 0.185±0.059) mg/L·h.; whereas the pharmacokinetic parameters for the rats in the blood-stasis model group after oral gavage of XFZYT, XFZYT-JG, XFZYT-NX, and XFZYT-JG-NX were Cmax = (0.315±0.153, 0.215±0.044, 0.228±0.056, 0.248±0.09) mg/L, Tmax = (0.5±0, 0.667±0.129, 0.5±0, 0.542±0.102) h, t1/2 = (0.408±0.146, 0.813±0.135, 0.708±0.383, 0.741±0.173) h, and AUC0-∞ = (0.306±0.157, 0.408±0.136, 0.368±0.159, 0.381±0.246) mg/L·h. CONCLUSION: The guiding herbs, Radix platycodonis and Radix cyathulae, significantly increased the absorption amount and rate of paeoniflorin in XFZYT, and accelerated its elimination from the blood.

IL-33 Provides Neuroprotection through Suppressing Apoptotic, Autophagic and NF-κB-Mediated Inflammatory Pathways in a Rat Model of Recurrent Neonatal Seizure.

Interleukin-33 (IL-33) is a novel identified chromatin-associated cytokine of IL-1 family cytokines. It signals through a heterodimer comprised of ST2L and IL-1RAcp, and plays a crucial role in many diseases. However, very little is known about the role and underlying intricate mechanisms of IL-33 in recurrent neonatal seizure (RNS). To determine whether IL-33 plays an important regulatory role, we established a neonatal seizure model in this study. Rats were subjected to recurrent seizures induced by inhaling volatile flurothyl. Recombinant IL-33 or PBS were also administered by intraperitoneally (IP) before surgery, respectively. Here, our current results indicated that RNS contributed to a significant reduction in IL-33 and its specific receptor (ST2L) expressions in cortex. While, in hippocampus, RNS induced an increase in IL-33 and ST2L evidently, compared with Sham group. After injection with IL-33, however, a remarkable increase in total IL-33 was detected both in brain cortex and hippocampus. In addition, IL-33 was mainly co-localized in the nuclear of GFAP+ astrocytes and the cytoplasm of the Iba-1+ microglia and IL-33+/NeuN+ merged cells. In parallel, ST2L was expressed mainly in the membrane of GFAP+ astrocytes, Iba-1+ microglia and NeuN+ neurons, respectively. Furthermore, administration of IL-33 improved RNS-induced behavioral deficits, promoted bodyweight gain, and ameliorated spatial learning and memory ability. Moreover, IL-33 pretreatment blocked the activation of NF-κB, resisted inflammatory cytokines IL-1ß and TNF-α increase, as well as suppressed apoptosis and autophagy activation after RNS. Collectively, IL-33 provides potential neuroprotection through suppressing apoptosis, autophagy and at least in part by NF-κB-mediated inflammatory pathways after RNS.

IL-33 Exerts Neuroprotective Effect in Mice Intracerebral Hemorrhage Model Through Suppressing Inflammation/Apoptotic/Autophagic Pathway.

Interleukin-33 (IL-33) is a recently identified member of the IL-1 family that exerts biologic functions by binding to a heterodimer composed of IL-1 receptor-related protein ST2L and IL-1RAcP. However, the role of IL-33 and whether IL-33 accounts for inflammation, apoptotic, and autophagic neuropathology after intracerebral hemorrhage (ICH) are not clear. Here, we established a mouse ICH model in this study, to determine the role of IL-33 and explore the underlying mechanism. Male mice were subjected to an infusion of type IV collagenase/saline into the left striatum to induce ICH/sham model. IL-33, soluble ST2 (sST2), or saline were also administered by a single intracerebroventricular (i.c.v.) injection, respectively. The results showed that the expression level of IL-33 markedly decreased within 6 h and reached the valleys at 6 and 72 h after ICH vs. sham group. In parallel, ST2L (a transmembrane form receptor of IL-33) significantly increased within 6 h and reached the peaks at 6 h and 24 h after ICH vs. sham group. In addition, administration of IL-33 alleviated cerebral water contents, reduced the number of PI- and TUNEL-positive cells, and improved neurological function after ICH. Moreover, IL-33 treatment apparently suppressed the expression of pro-inflammation cytokines IL-1ß and TNF-α, evidently increased Bcl-2 but decreased cleaved-caspase-3, and obviously decreased the levels of autophagy-associated proteins LC3-II and Beclin-1 but maintained P62 at high level after ICH. On the contrary, treatment with sST2, a decoy receptor of IL-33, exacerbated ICH-induced brain damage and neurological dysfunction by promoting apoptosis, and enhancing autophagic activity. In conclusion, IL-33 provides neuroprotection through suppressing inflammation, apoptotic, and autophagic activation in collagenase-induced ICH model.

[Expression of cathepsin-B and -D in rat's brain after traumatic brain injury].

OBJECTIVE: To study the expression of cathepsin-B and -D in different time point after traumatic brain injury. METHODS: Traumatic brain injury (TBI) model was established on rats, cathepsin-B and cathepsin-D immunofluorescence staining and confocal microscope analysis were performed. Positive cells were counted by confocal microscope and image analysis techniques were used to determine the morphological changes in each group. RESULTS: Immunofluorescence staining results showed that cathepsin-B was activated 1 hour after TBI while cathepsin-D was not activated until 12hour after TBI. Both of them got to their peak during 4 to 8days, and kept a high level of activating 32days after TBI. Cathepsin-B and -D positive cells did not merge with caspase-3 positive cells until 6 h after TBI. CONCLUSION: Cathepsin-B and -D could be the diagnostic markers of TBI and can estimating time course of lateral TBI. They blocked caspase-3 activation at the beginning period after TBI and started to promote cell death with caspase-3 6 h after TBI.

Mismatch negativity, social cognition, and functional outcomes in patients after traumatic brain injury.

Mismatch negativity is generated automatically, and is an early monitoring indicator of neuronal integrity impairment and functional abnormality in patients with brain injury, leading to decline of cognitive function. Antipsychotic medication cannot affect mismatch negativity. The present study aimed to explore the relationships of mismatch negativity with neurocognition, daily life and social functional outcomes in patients after brain injury. Twelve patients with traumatic brain injury and 12 healthy controls were recruited in this study. We examined neurocognition with the Wechsler Adult Intelligence Scale-Revised China, and daily and social functional outcomes with the Activity of Daily Living Scale and Social Disability Screening Schedule, respectively. Mismatch negativity was analyzed from electroencephalogram recording. The results showed that mismatch negativity amplitudes decreased in patients with traumatic brain injury compared with healthy controls. Mismatch negativity amplitude was negatively correlated with measurements of neurocognition and positively correlated with functional outcomes in patients after traumatic brain injury. Further, the most significant positive correlations were found between mismatch negativity in the fronto-central region and measures of functional outcomes. The most significant positive correlations were also found between mismatch negativity at the FCz electrode and daily living function. Mismatch negativity amplitudes were extremely positively associated with Social Disability Screening Schedule scores at the Fz electrode in brain injury patients. These experimental findings suggest that mismatch negativity might efficiently reflect functional outcomes in patients after traumatic brain injury.