Dynamic Changes and Effects of H2S, IGF-1, and GH in the Traumatic Brain Injury.

The aim of this study was to examine the expression changes of H2S, IGF-1, and GH in traumatic brain injury (TBI) patients and to detect their neuroprotective functions after TBI. In this study, we first collected cerebrospinal fluid (CSF) and plasma from TBI patients at different times after injury and evaluated the concentrations of H2S, IGF-1, and GH. In vitro studies were using the scratch-induced injury model and cell-cell interaction model (HT22 hippocampal neurons co-cultured with LPS-induced BV2 microglia cells). In vivo studies were using the controlled cortical impact (CCI) model in mice. Cell viability was assessed by CCK-8 assay. Pro-inflammatory cytokines expression was determined by qRT-PCR, ELISA, and nitric oxide production. Western blot was performed to assess the expression of CBS, CSE, IGF-1, and GHRH. Moreover, the recovery of TBI mice was evaluated for behavioral function by applying the modified Neurological Severity Score (mNSS), the Rotarod test, and the Morris water maze. We discovered that serum H2S, CSF H2S, and serum IGF-1 concentrations were all adversely associated with the severity of the TBI, while the concentrations of IGF-1 and GH in CSF and GH in the serum were all positively related to TBI severity. Experiments in vitro and in vivo indicated that treatment with NaHS (H2S donor), IGF-1, and MR-409 (GHRH agonist) showed protective effects after TBI. This study gives novel information on the functions of H2S, IGF-1, and GH in TBI.

Identification of BST2 Contributing to the Development of Glioblastoma Based on Bioinformatics Analysis.

Rigorous molecular analysis of the immune cell environment and immune response of human tumors has led to immune checkpoint inhibitors as one of the most promising strategies for the treatment of human cancer. However, in human glioblastoma multiforme (GBM) which develops in part by attracting immune cell types intrinsic to the human brain (microglia), standard immunotherapy has yielded inconsistent results in experimental models and patients. Here, we analyzed publicly available expression datasets to identify molecules possibly associated with immune response originating from or influencing the tumor microenvironment in primary tumor samples. Using three glioma datasets (GSE16011, Rembrandt-glioma and TCGA-glioma), we first analyzed the data to distinguish between GBMs of high and low tumor cell purity, a reflection of the cellular composition of the tumor microenvironment, and second, to identify differentially expressed genes (DEGs) between these two groups using GSEA and other analyses. Tumor purity was negatively correlated with patient prognosis. The interferon gamma-related gene BST2 emerged as a DEG that was highly expressed in GBM and negatively correlated with tumor purity. BST2 high tumors also tended to harbor PTEN mutations (31 vs. 9%, BST2 high versus BST2 low ) while BST2 low tumors more often had sustained TP53 mutations (8 versus 36%, BST2 high versus BST2 low ). Prognosis of patients with BST2 high tumors was also poor relative to patients with BST2 low tumors. Further molecular in silico analysis demonstrated that high expression of BST2 was negatively correlated with CD8+ T cells but positively correlated with macrophages with an M2 phenotype. Further functional analysis demonstrated that BST2 was associated with multiple immune checkpoints and cytokines, and may promote tumorigenesis and progression through interferon gamma, IL6/JAK/STAT3 signaling, IL2/STAT5 signaling and the TNF-α signaling via NF-kB pathway. Finally, a series of experiments confirmed that the expression of BST2 can be significantly increased by IFN induction, and knockdown of BST2 can significantly inhibit the growth and invasion of GBM cells, and may affect the phenotype of tumor-associated macrophages. In conclusion, BST2 may promote the progression of GBM and may be a target for treatment.

Inhibition of microRNA-203 protects against traumatic brain injury induced neural damages via suppressing neuronal apoptosis and dementia-related molecues.

BACKGROUND: Traumatic brain injury (TBI) can lead to cognitive dysfunction and motor dysfunction. TBI is a potential risk factor for subsequent dementia. Hyperphosphorylation of Tau and ApoE4 has been found in patients with TBI. A significant increase in miR-203 was also found in the peripheral blood of TBI mice. Thus, we hypothesize that miR-203 inhibitor protects against neuronal damage and behavioral deficits by inhibition of Tau phosphorylation, ApoE4 expression and apoptosis. METHODS: TBI mice were induced and treated with miR-203 inhibitor. Tau phosphorylation and ApoE4, hippocampal long-term potentiation (LTP), learning and memory, and motor function were separately detected by Western blot analysis, electrophysiology recording and behavioral assessments including Morris water maze test, beam-balance test, beam-walk test and rotarod test. Caspase-3 activity and bcl-2 expression were detected by ELISA. RESULTS: TBI induction led to increased phosphorylation of Tau and ApoE4 expression. Administration of miR-203 inhibitor suppressed TBI induced ApoE4 expression and Tau hyperphosphorylation, rescued TBI mediated hippocampal LTP deficits and hippocampus dependent learning and memory dysfunction. miR-203 inhibitor treatment also improved motor function. In addition, miR-203 inhibitor treatment inhibited neuronal apoptosis by inhibiting caspase-3 activity and increasing bcl-2 expression. CONCLUSION: miR-203 inhibitor treatment can rescue TBI-induced neural damage by inhibiting neuronal apoptosis and dementia markers like ApoE4 expression and Tau phosphorylation.

Docosahexaenoic Acid Protects Traumatic Brain Injury by Regulating NOX2 Generation via Nrf2 Signaling Pathway.

Docosahexaenoic acid (DHA) is verified to have neuroprotective effects on traumatic brain injury (TBI) rats by activating Nrf2 signaling pathway, but the role of NOX2 in this effect has not been illuminated. So this study explored the role of NOX2 in TBI models treated with DHA, aiming to complete the mechanism of DHA. TBI rat models were constructed with or without DHA treatment, and H2O2-induced hippocampal neurons were pretreated with DHA alone or in combination with Nrf2 inhibitor brusatol. The neurological function, cognitive ability, and cerebral edema degree of rats were assessed. The apoptosis rate and viability of cells was measured. The generation of NOX2, Nrf2, HO-1 and NQO-1 expression levels, and ROS content in hippocampal CA1 region and hippocampal neurons were detected. DHA could not only improve the neurological function, brain edema and cognitive ability in TBI rats, but also decrease effectively the contents of NOX2 and ROS in hippocampal CA1 region and hippocampal neurons. DHA promoted the nuclear transposition of Nrf2 and the expression levels of HO-1 and NQO-1 in hippocampal CA1 region and hippocampal neurons. On the contrary, Nrf2 inhibitor brusatol inhibited the nuclear transposition of Nrf2 and the expression levels of HO-1 and NQO-1 in hippocampal neurons, promoted the generation of ROS and NOX2, and accelerated cell apoptosis. Both in vivo and in vitro experiments demonstrated that DHA treated TBI by reducing NOX2 generation that might function on Nrf2 signaling pathway, providing a potential evidence for its clinical application.

Docosahexaenoic acid ameliorates traumatic brain injury involving JNK-mediated Tau phosphorylation signaling.

Hyperphosphorylation of Tau has been found in patients with traumatic brain injury (TBI). Inhibition of c-Jun N-terminal kinases (JNKs) improves neurological function by suppressing Tau phosphorylation. By inhibiting JNK, docosahexaenoic acid (DHA) protects against cognitive decline in a mouse model of Alzheimer's disease (AD). We hypothesize that DHA protects against neuronal damage and behavioral deficits by inhibition of JNK mediated Tau phosphorylation. We induced TBI in mice and examined the phosphorylation status of JNK and Tau. We treated TBI and sham operated mice with DHA, and investigated the effects of DHA on JNK and Tau phosphorylation, hippocampal long term potentiation (LTP), learning and memory, and motor function by Western blot analysis, electrophysiology recording and behavioral assessments including Morris water maze test, beam-balance test, beam-walk test and rotarod test. We found that TBI induction lead to increased phosphorylation of JNK and Tau. DHA suppressed TBI induced JNK and Tau hyperphosphorylation, rescued TBI mediated hippocampal LTP deficits and hippocampus dependent learning and memory dysfunction, and improved motor function. Inhibition of JNK and Tau phosphorylation by DHA may represent a potential therapeutic strategy for TBI induced neurological dysfunction and Tauopathy.

Amyloid-ß immunization enhances neurogenesis and cognitive ability in neonatal mice.

Whether Aß actually has a physiological as well as a pathological role is not known. In order to investigate the effect of endogenous Aß, wild type C57BL/6 mice were immunized with human or mouse derived Aß1-42. The anti-Aß antibody concentrations were increased in both treated groups. Compared to the human Aß1-42 treated group, level of serum Aß significantly decreased in mouse Aß1-42 treated group. Western blot results revealed that these two derived Aß1-42 had no cross-reaction. The new dentate granule survival cells increased in Aß1-42 immunization groups, indicated by more BrdU+/NeuN+ and BrdU+/DCX+ cells as compared to PBS-treated group, accompanied by behavioral performance improving in a hippocampus-dependent learning task. Immunohistochemical analysis showed that BrdU+/Iba1+ cells also increased, however new born astrocytes (BrdU+/GFAP+) were unaffected in all treated mice. Interestingly, according the results of ELISA analysis both vaccines up-regulated IL-4 and IFN-γ levels in the brains and sera, but the TNF-α level did not changed. Of note, human Aß1-42 immunization in neonatal mice enhanced neurogenesis and cognitive ability, might via Aß immune response rather than cleaning endogenous Aß.

Increased serum levels of brain-derived neurotrophic factor in autism spectrum disorder.

The aim of this study was to investigate the potential role of brain-derived neurotrophic factor (BDNF) in children with autism spectrum disorders (ASD) by measuring serum circulating levels of BDNF as well as calcium and comparing them with age-matched and sex-matched normal controls. The study included 75 drug-naive ASD children and 75 age-sex-matched healthy children. The concentration of serum BDNF was determined using the enzyme-linked immunosorbent assay method at baseline. Clinical information was collected. The severity of ASD was assessed at admission using the Childhood Autism Rating Scale total score. The results indicated that the mean serum BDNF levels were significantly (P<0.0001) higher in children with ASD compared with the control cases (17.59±5.55 vs. 11.21±2.79 ng/ml; t=8.902). On the basis of the receiver operating characteristic curve, the optimal cutoff value of serum BDNF levels as an indicator for auxiliary diagnosis of autism was projected to be 12.65 ng/ml, which yielded a sensitivity of 80.8% and a specificity of 70.2%; the area under the curve was 0.840 [95% confidence interval (CI), 0.777-0.904]. In univariate logistic regression analysis, with an unadjusted odds ratio of 9.42 (95% CI, 4.33-25.95; P<0.0001), BDNF of 12.65 ng/ml or more had an association with a diagnosis of ASD. After adjusting for possible covariates, BDNF of 12.65 ng/ml or more is still an independent indicator of ASD, with an adjusted odds ratio of 7.33 (95% CI, 2.98-16.55; P<0.0001). Serum BDNF levels may be associated independently with the severity of ASD, and higher BDNF levels could be considered an independent diagnostic marker of ASD.

Resistin protection against endogenous Aß neuronal cytotoxicity from mitochondrial pathway.

Neurotoxicity of amyloid ß (Aß) plays an important role in Alzheimer's disease (AD) pathogenesis. In this study, we researched the potential protective effects of resistin against Aß neurotoxicity in mouse Neuro2a (N2a) cells transfected with the Swedish amyloid precursor protein (Sw-APP) mutant and Presenilin exon 9 deletion mutant (N2a/D9), which overproduced Aß with abnormal intracellular Aß accumulation. The results show increased levels of ROS, NO, protein carbonyls, and 4HNE in N2a/D9 cells, which were attenuated by resistin treatment in a dose dependent manner. We also found that resistin could improve mitochondrial function in N2a/D9 cells through increasing the level of ATP and mitochondrial membrane potential. MTT and LDH assay indicated that N2a/D9 cells show increased vulnerability to H2O2-induced insult, which could be ameliorated by resistin. Mechanically, we found that resistin prevented apoptosis signals through reducing the ratio of Bax/Bcl2, the level of cleaved caspase-3, and attenuating cytochrome C release. Finally, the results demonstrated that resistin did not change the production of Aß1-40 and Aß1-42 in N2a/D9 cells, which suggests that the protective effects of resistin are independent of APP metabolism. This raises the possibility of novel AD therapies using resistin.