Study on the preventive effect of schisandrin on neural tube defects in mice and its mechanism / 解放军医学杂志

Objective To investigate the preventive effect of schisandrin(SCH)on fetal neural tube defects(NTDs)of mice and its mechanism.Methods C57BL/6 mice were mated with female and male at a ratio of 2:1.Pregnant female mice with vaginal plug after mating were randomly divided into control group,model group,SCH group,and folic acid group,with 9 mice in each group.The NTDs fetal mice model was induced by intraperitoneal injection of all-trans retinoic acid(atRA)(7.5 mg/kg)on embryonic day 7.5(E 7.5 d).During E 0.5 d-E 11.5 d,pregnant rats in folic acid group were given folic acid[61.0 μg/(kg·d)]by gavage once a day,and pregnant rats in SCH group were given SCH[8.0 mg/(kg·d)]by gavage once a day.Fetal mice were removed by cesarean section on E 11.5 d.PC12 cells were divided into control group,model group and SCH group.PC12 cells were treated with atRA(20 μmol/L)for 12 hours to establish cell damage model in model group,and treated with SCH(2.5 μmol/L)for 24 hours in SCH group.Fetuses were identified NTDs by stereoscopic microscopy.HE staining was used to observe the closure of the neural tube.The expression levels of p-PI3K,Akt and p-Akt molecules in PI3K/Akt signaling pathway were detected by Western Blotting.Results Compared with control group,the incidence of NTDs was significantly increased in mice of model group(P<0.01);compared with model group,the incidence of NTDs was decreased in folic acid group and SCH group(P<0.01);compared with folic acid group,SCH group had a lower incidence of NTDs(P<0.01).Western Blotting results showed that compared with control group,the expression of p-PI3K and p-Akt protein in fetal tissues of model group was significantly decreased(P<0.01,P<0.05);compared with model group,there was no significant difference in expression of p-PI3K and p-Akt in fetal tissues of folic acid group(P>0.05),while the expression of p-PI3K and p-Akt protein in SCH group was significantly higher(P<0.05).Compared with control group,PC12 cells in model group showed lower expression levels of p-PI3K and p-Akt(P<0.05);compared with model group,PC12 cells in SCH group showed higher expression levels of p-PI3K and p-Akt(P<0.05).Conclusions SCH can reduce the incidence of atRA-induced NTDs in fetal mice,and its preventive effect is better than folic acid,which may be related to the activation of the PI3K/Akt signaling pathway.

GLPS improves EAE demyelination through inhibition of TLR4/NF-KB pathway / 中国药理学通报

Aim To explore the protective effects of ganoderma lucidum polysaccharides (GLPS) on experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS) and the underlying mechanism. Methods Thirty C57BL/6 mice were randomly divided into three groups: normal control group, EAE model group and GLPS group (5 mg • kg

Procyanidin B2 protects H / 中国药理学通报

Aim To explore the protective effect of proanthocyanidin B2 (PC-B2) on oxidative damage of PC 12 cells induced by hydrogen peroxide (H

Mechanism of bilobalide promoting neuroprotection of macrophages / 中国中药杂志

This study aims to explore the neuroprotective effect of bilobalide(BB) and the mechanisms such as inhibiting inflammatory response in macrophage/microglia, promoting neurotrophic factor secretion, and interfering with the activation and differentiation of peripheral CD4~+ T cells. BB of different concentration(12.5, 25, 50, 100 μg·mL~(-1)) was used to treat the RAW264.7 and BV2 cells for 24 h. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay and cell counting kit-8(CCK-8) were employed to detect the cytotoxicity of BB and appropriate concentration was selected for further experiment. Lipopolysaccharide(LPS) was applied to elicit inflammation in RAW264.7 and BV2 cells, mouse bone marrow-derived macrophages(BMDMs), and primary microglia, respectively. The effect of BB on cell proliferation and secretion of inflammatory cytokines and neurotrophic factors was detected by enzyme-linked immunosorbent assay(ELISA). Spleen monocytes of C57BL/6 female mice(7-8 weeks old) were isolated, and CD4~+ T cells were separated by magnetic beads under sterile conditions. Th17 cells were induced by CD3/CD28 and the conditioned medium for eliciting the inflammation in BMDMs. The content of IL-17 cytokines in the supernatant was detected by ELISA to determine the effect on the activation and differentiation of CD4~+ T cells. In addition, PC12 cells were incubated with the conditioned medium for eliciting inflammation in BMDMs and primary microglia and the count and morphology of cells were observed. The cytoto-xicity was determined by lactate dehydrogenase(LDH) assay. The result showed that BB with the concentration of 12.5-100 μg·mL~(-1) had no toxicity to RAW264.7 and BV2 cells, and had no significant effect on the activity of cell model with low inflammation. The 50 μg·mL~(-1) BB was selected for further experiment, and the results indicated that BB inhibited LPS-induced secretion of inflammatory cytokines. The experiment on CD4~+ T cells showed that the conditioned medium for LPS-induced inflammation in BMDMs promoted the activation and differentiation of CD4~+ T cells, while the conditioned medium of the experimental group with BB intervention reduced the activation and differentiation of CD4~+ T cells. In addition, BB also enhanced the release of neurotrophic factors from BMDMs and primary microglia. The conditioned medium after BB intervention can significantly reduce the death of PC12 neurons, inhibit neuronal damage, and protect neurons. To sum up, BB plays a neuroprotective role by inhibiting macrophage and microglia-mediated inflammatory response and promoting neurotrophic factors.

Grape Seed Extract Attenuates Demyelination in Experimental Autoimmune Encephalomyelitis Mice by Inhibiting Inflammatory Response of Immune Cells / 中国结合医学杂志

OBJECTIVE@#To examine the anti-inflammatory effect of grape seed extract (GSE) in animal and cellular models and explore its mechanism of action.@*METHODS@#This study determined the inhibitory effect of GSE on macrophage inflammation and Th1 and Th17 polarization in vitro. Based on the in vitro results, the effects and mechanisms of GSE on multiple sclerosis (MS)-experimental autoimmune encephalomyelitis (EAE) mice model were further explored. The C57BL/6 mice were intragastrically administered with 50 mg/kg of GSE once a day from the 3rd day to the 27th day after immunization. The activation of microglia, the polarization of Th1 and Th17 and the inflammatory factors such as tumor necrosis factor- α (TNF- α), interleukin-1 β (IL-1 β), IL-6, IL-12, IL-17 and interferon-γ (IFN-γ) secreted by them were detected in vitro and in vivo by flow cytometry, enzyme linked immunosorbent assay (ELISA), immunofluorescence staining and Western blot, respectively.@*RESULTS@#GSE reduced the secretion of TNF-α, IL-1 β and IL-6 in bone marrow-derived macrophages stimulated by lipopolysaccharide (P<0.01), inhibited the secretion of TNF-α, IL-1 β, IL-6, IL-12, IL-17 and IFN-γ in spleen cells of EAE mice immunized for 9 days (P<0.05 or P<0.01), and reduced the differentiation of Th1 and Th17 mediated by CD3 and CD28 factors (P<0.01). GSE significantly improved the clinical symptoms of EAE mice, and inhibited spinal cord demyelination and inflammatory cell infiltration. Peripherally, GSE downregulated the expression of toll-like-receptor 4 (TLR4) and Rho-associated kinase (ROCKII, P<0.05 or P<0.01), and inhibited the secretion of inflammatory factors (P<0.01 or P<0.05). In the central nervous system, GSE inhibited the infiltration of CD45+CD11b+ and CD45+CD4+ cells, and weakened the differentiation of Th1 and Th17 (P<0.05). Moreover, it reduced the secretion of inflammatory factors (P<0.01), and prevented the activation of microglia (P<0.05).@*CONCLUSION@#GSE had a beneficial effect on the pathogenesis and progression of EAE by inhibiting inflammatory response as a potential drug and strategy for the treatment of MS.

Antagonizing astrocytic platelet activating factor receptor-neuroinflammation for total flavone of epimedium in response to cuprizone demyelination.

Demyelinating diseases of the central nervous system are characterized by recurrent demyelination and progressive neurodegeneration, but there are no clinical drugs targeting myelin regeneration or improving functional disability in the treatment of multiple sclerosis. Total flavone of Epimedium (TFE) is the main active components of Epimedium, which exhibits the beneficial biological activities in the treatment of diseases, but there is no report in the treatment of demyelinating disorder. The purpose of this study was to explore the therapeutic potential and possible mechanism of TFE in the treatment of demyelination. The results showed that TFE efficiently improved the behavioural performance and histological demyelination in cuprizone (CPZ)-induced demyelinating model. In terms of action, TFE increased astrocytes enrichment in corpus callosum, striatum and cortex, and promoted astrocytes to express neurotrophic factors. Furthermore, the expression of platelet-activating factor receptor (PAFR) in astrocytes was induced by CPZ feeding and LPS stimulation, accompanied by the increase of inflammatory cytokines TNF-α,IL-6 and IL-1ß. TFE declined the expression of PAFR, and inhibited inflammatory response. At the same time, TFE also antagonized PAFR activation and inflammatory response triggered by PAF, which further confirmed that TFE, as a new PAFR antagonist, inhibited the astrocyte-derived inflammatory response by antagonizing PAFR-neuroinflammation axis, thus contributing to myelin protection and regeneration.

Neuroprotective Mechanism of Buyang Huanwu Tang on Experimental Autoimmune Encephalomyelitis Mice / 中国实验方剂学杂志

Objective:To explore the neuroprotective effect and mechanism of Buyang Huanwu Tang (BYHWT) on experimental autoimmune encephalomyelitis (EAE) at different stages. Method:The 36 female C57BL/6 mice were immunized subcutaneously with myelin oligodendrocyte glycoprotein peptides (MOG35-55),then randomly divided into 9, 17, 28 d EAE control group. Each BYHWT group was orally given drugs on the 3rd day after immunization (50 g·kg-1·d-1), and EAE control group was given the same volume of normal saline in the same way once a day for 9, 17 and 28 d after immunization. The effect of BYHWT on EAE mice was observed with internationally accepted clinical score. Brain and spinal cord specimens were collected at 9, 17 and 28 d after immunization. The neuroprotective effect of BYHWT was observed by hematoxylin-eosin(HE)staining and solid blue staining (LFB). The expressions of BDNF and GAP-43 in spinal cord and brain were detected by Western blot. Result:After treatment, BYHWT can significantly inhibit myelitis cell infiltration and alleviate myelin loss. Compared with EAE group, the expression of Nogo-A in the spinal cord of each BYHWT group was significantly down-regulated (PPPPConclusion:BYHWT can improve the local nerve growth microenvironment and promote the expression of NTFs, reduce the expressions of neuroinhibitory factors, and play a role in neuroprotection.

The effects of catechin on inflammatory response induced by lipopolysaccharide in BV-2 cells / 药学学报

The effects of catechin on inflammatory response of BV-2 cells were investigated using the lipopolysaccharide (LPS) model. BV-2 cells were incubated with LPS (1 mg·L-1) for 12 h in the microglia inflammatory model in vitro. After catechin and LPS co-incubation for 12 h, MTT, ELISA and Western blot were used to detect cell viability, cytokines, cell migration and protein expression. In addition, transwell assay was conducted to investigate the effect of catechin on cell chemokaxis. Catechin did not show any cytotoxicity effect on BV-2 cells, but reversed the change in cell morphology and inhibited the release of TNF-α and IL-1β, cell chemotaxis and phosphorylation of NF-κB/p65. In conclusion, Catechin could inhibit the LPS-induced inflammatory response in BV-2 cells.

A Novel Missense Mutation in Peripheral Myelin Protein-22 Causes Charcot-Marie-Tooth Disease / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Charcot-Marie-Tooth disease (CMT) is the most common inherited peripheral neuropathy. A great number of causative genes have been described in CMT, and among them, the heterozygous duplication of peripheral myelin protein-22 (PMP22) is the major cause. Although the missense mutation in PMP22 is rarely reported, it has been demonstrated to be associated with CMT. This study described a novel missense mutation of PMP22 in a Chinese family with CMT phenotype.</p><p><b>METHODS</b>Targeted next-generation sequencing (NGS) was used to screen the causative genes in a family featured with an autosomal dominant demyelinating form of CMT. The potential variants identified by targeted NGS were verified by Sanger sequencing and classified according to the American College of Medical Genetics and Genomics standards and guidelines. Further cell transfection studies were performed to characterize the function of the novel variant.</p><p><b>RESULTS</b>Using targeted NGS, a novel heterozygous missense variant in PMP22 (c.320G>A, p.G107D) was identified. In vitro cell functional studies revealed that mutant PMP22 protein carrying p.G107D mutation lost the ability to reach the plasma membrane, was mainly retained in the endoplasmic reticulum, and induced cell apoptosis.</p><p><b>CONCLUSIONS</b>This study supported the notion that missense mutations in PMP22 give rise to a CMT phenotype, possibly through a toxic gain-of-function mechanism.</p>

Fibronectin and neuroprotective effect of granulocyte colony-stimulating factor in focal cerebral ischemia.

Stroke is one of the leading causes of unnatural death and disability. No effective therapy is available. Recombinant human granulocyte colony-stimulating factor (rhG-CSF), as a mobilizing agent for bone marrow stem cells, can promote stem cell mobilization, homing to brain after cerebral ischemia. In the present study, the administration of G-CSF significantly increased number of CD34(+) cells in the marginal zone of the infarction. Rats receiving G-CSF had higher survival rate and lower infarction volume. Neurological behavior was improved, and the expression of fibronectin in the ischemic brain was increased, as compared to rats treated with vehicle. To mimic the ischemia-reperfusion injury in experimental animals, we employed hippocampal slice cultures that were first treated with oxygen and glucose deprivation (OGD) and then with oxygen-glucose resupply, finding that fibronectin significantly increased the neurite outgrowth of OGD hippocampal slices, upregulated the expression of Bcl-2 protein, and ameliorated the ultrastructure damage of OGD hippocampal slices.

Reductions in mRNA of the neuroprotective agent, neuroserpin, after cerebral ischemia/reperfusion in diabetic rats.

The aim of this study is to investigate disturbances in fibrinolytic components in diabetic rats with middle cerebral artery occlusion (MCAO). Comparison of cerebral injury at 23 h after reperfusion indicated that infarction volumes were increased in diabetic rats as compared with normal rats. Cerebral ischemia/reperfusion in normal and diabetic rats was accompanied by increased expression of tissue plasminogen activator (t-PA), urokinase plasminogen activator (u-PA), plasminogen activator inhibitor 1 (PAI-1) and neuroserpin (NSP) mRNA after reperfusion. Most importantly, the expression of NSP mRNA, but not t-PA, u-PA and PAI-1 mRNA, was reduced to undetectable levels at 11 and 23 h after reperfusion in diabetic rats as compared with normal rats. Although activity of PA (t-PA and u-PA) and the ratio of PA/PAI were increased at 5 h after reperfusion in both ischemic brains of diabetic and normal rats, the levels in diabetic rats were lower than that in normal rats. We speculate that the exacerbation of ischemic injury in diabetic rats may be related to the reduction of fibrinolytic component and the neuroprotective role of NSP. Further study of the efficacy of NSP in the pathogenesis and treatment of cerebral ischemia may provide novel insights.

Modulation effects of human immature and mature dendritic cells on glatiramer acetate specific T cell lines in vitro / 中国实验血液学杂志

A large body of evidence demonstrates that dendritic cells (DC) play a pivotal role in the control of immunity by priming and tolerizing T cells. In multiple sclerosis (MS), autoreactive T cells are proposed to play a pathogenic role by secreting pro-inflammatory cytokines, but comparison studies on the effects of immature and mature dendritic cells on the cytokines profile of antigen-specific T cell lines are lacking. To evaluate the actions of dendritic cell maturation on T cell polarization, the effects of immature and mature dendritic cells derived from MS patients on in vitro proliferative responses, and cytokine production by glatiramer acetate (GA)- specific T cell lines (TCL) derived from MS patients were analyzed. The results demonstrated that it is easy to derive GA-specific TCL from MS patients with high specificity; lipopolysaccharide can efficiently induce DC maturation within 24 hours at a concentration of 5 micro g/ml; mature DC showed higher co-stimulatory capacity of GA-specific TCLs than immature DC. GA-specific TCLs produce dominantly IL-2, IL-4, IFN-gamma and IL-10, but low levels of IL-6. In contrast to immature DC, mature DC enhanced capacity to induce IL-6 and IL-10 secretion, but down-regulate IL-2, IL-4 and IFN-gamma production by GA- specific TCLs. It is concluded that DC maturation status modulating proliferation of TCL and production of cytokines may represent another focus for the study on both immuno-pathogenesis and immunotherapeutic interventions in MS.

Influence of gamma irradiation on phenotype and function of human dendritic cells in vitro / 中国实验血液学杂志

To determine whether gamma irradiation influences phenotype and function of human dendritic cells (DC) in vitro, dendritic cells were induced from the peripheral blood mononuclear cells of multiple sclerosis patients with RPMI 1640 medium containing recombinant human GM-CSF (rhGM-CSF, 800 U/ml) and recombinant human IL-4 (rhIL-4, 500 U/ml). Phenotypic changes were monitored by light microscopy. Lipopolysaccharide at a concentration of 5 micro g/ml was added into the cultures after 6 days of growth for DC complete maturation, and the cells were cultured for another 24 hours. The harvested DC on day 7 were divided equally into several parts. One part was used as non-irradiated DC (naive DC) while the other parts were irradiated by gamma ray at a dose of 25 Gy and 30 Gy respectively. Cell surface molecules were analyzed by flow cytometry. The capability of DC to stimulated autologous T cell proliferation were determined. The results showed that gamma irradiation reduced expression of CD86, CD80 and HLA-DR molecules on dendritic cells, especially CD86 molecules. Dendritic cells effectively stimulated autologous T cells proliferation while irradiated DC in all groups showed profound decrease of capability to promote T cells proliferation. It is concluded that gamma irradiation of dendritic cells not only influenced phenotype of DC but also altered their function as stimulator cells in mixed lymphocyte reaction.