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Probiotic intervention is an effective strategy to alleviate oxidative stress-related diseases. Our previous studies found that Lactiplantibacillus plantarum NJAU-01 (NJAU-01) exhibited antioxidant effects in a D-galactose (D-gal)-induced aging mouse model. However, the underlying mechanism remains to be unveiled. This study was aimed to investigate the ameliorative effect and mechanism of NJAU-01 against oxidative stress induced by D-gal. The results showed that NJAU-01 could reverse the tendency of a slow body weight gain induced by D-gal. NJAU-01 relieved hepatic oxidative stress via increasing the hepatic total antioxidant capacity and antioxidant enzyme activities including superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT). Moreover, the malondialdehyde (MDA) level was reversed after NJAU-01 supplementation. The proteomic results showed that there were 201 differentially expressed proteins (DEPs) between NJAU-01 and D-gal groups. NJAU-01 regulated the expressions of glutathione S -transferase Mu 5 (Gstm5), glutathione S -transferase P2 (Gstp2) and NADH dehydrogenase 1α subcomplex subunit 7 (Ndufa7) related to oxidative stress, and autophagy protein 5 (Atg5) and plasma alpha-L-fucosidase (Fuca2) involved in autophagy, etc . 16S rDNA sequencing results showed that NJAU-01 supplementation could regulate the gut microbiota dysbiosis induced by D-gal via increasing the relative abundances of the phylum Firmicutes and the genus Lactobacillus and reducing the relative abundances of the phylum Bacteroidetes and the genera Lachnospiraceae _NK4A136_group as well as Prevotellaceae _UCG-001, etc. . Spearman correlation analysis results showed that the altered gut microbiota composition had a significant correlation with antioxidant enzyme activities and the DEPs related to oxidative stress. Overall, NJAU-01 alleviated hepatic oxidative stress induced by D-gal via manipulating the gut microbiota composition and hepatic protein expression profile.

In this paper, the protein changes during aging and the differences in the myofibrillar protein fraction at 1 h postmortem of pale, soft and exudative (PSE), and red, firm and non-exudative (RFN) pork longissimus thoracis (LT) were comparatively studied. The PSE and RFN groups were screened out based on the differences in their pH and lightness ( L* ) at 1 h, and their purge loss at 24 h postmortem. Based on the measured MFI, desmin degradation, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, PSE meat presented more significant changes in the myofibrillar protein fraction compared to RFN meat during postmortem aging. Through liquid chromatograph-mass spectrometer/mass spectrometer (LC-MS/MS) analysis, a total of 172 differential proteins were identified, among which 151 were up-regulated and 21 were down-regulated in the PSE group. The differential proteins were muscle contraction, motor proteins, microfilaments, microtubules, glycolysis, glycogen metabolism, energy metabolism, molecular chaperones, transport, and enzyme proteins. The AMP activated protein kinase (AMPK) signaling pathway, HIF-1 signaling pathway, calcium signaling pathway, and PI3K-Akt signaling pathway were identified as the significant pathways related to meat quality. This study suggested that the different changes of the myofibrillar protein fraction were involved in the biochemical metabolism in postmortem muscle, which may contribute to the molecular understanding of PSE meat formation.

Objective: To investigate the clinical features of pregnant women with thalassemia in non endemic area, and to prevent the births of babies with intermedia or major thalassemia., Methods: Two hundred and thirty-five pregnants women with thalassemia diagnosed from March 2015 to April 2016 in our hospital were enrolled and retrospectively analysed. The blood routine and hemoglobin electrophoresis were performed respectively by XN-9000 automatic blood cell analyzer and HYDRASYS hemoglobin electrophoresis apparatus. The three commonest deletion of α-thalassemia, the three non-deletion α-thalassemia and 21 known β-thalassemia mutation were all detected by fluorescence melting curve analysis., Results: Among 235 pregnant women of thalassemia, the majority were β-thalassemia, which were followed by α-thalassemia and composite thalassemia. Most pregnant women showed a mild anemia, and suffered from microcytic anemia, but less suffered from iron deficiency anemia. The ratio of second-child pregnant women was increased, and the ratio was close to one third both in α-thalassemia and β-thalassemia patients, and 75% patients were composite thalassemia. HbF was found to be more in native pregnant women with β-thalassemia. Hemoglobin isomer was easy to found in the pregnant with α-thalassemia, and they were all non native. The genotype of -- sea were found majority in both native and non native pregnant women with thalassemia. The genotype of IVS-II-654 made up a large majority(55.38%) in native pregnant with β-thalassemia, as well as one of whose parents was native pregnant women. The genotypes of CD41-42,IVS-II-654 and CD17 were found to be a large majority in non native pregnant women, each of them accounted for 30%., Conclusion: More pregnant women with thalassemia are founded to be in non endemic area, and shows their own unique clinical features. It is certainly to detect thalassemia mutation in their spouse and their babies, to prevent the births of babies with intermedia or major thalassemia.

miR-134 has been shown to be associated with angiogenesis and the progression of osteosarcoma. This study further assessed the effects of miR-134 expression on osteosarcoma cell migration, invasion, and metastasis in vitro and in a nude mouse xenograft model, exploring the underlying molecular events. Luciferase reporter assays revealed that miR-134 directly targets the 3'-UTRs of MMP1 and MMP3 to reduce their expression in osteosarcoma cells. In conclusion, overexpression of miR-134 suppresses osteosarcoma cell invasion and metastasis through the inhibition of MMP1 and MMP3 expression. We propose miR-134 as an attractive novel therapeutic target for the treatment of osteosarcoma., (© 2019 Federation of European Biochemical Societies.)

Background: Protein oxidation is widespread in biochemical systems. The objective of the study was to investigate the differences in protein oxidation, μ-calpain activity, desmin proteolysis and protein solubility of beef psoas major (PM) and semi-membranosus (SM) muscles under three packaging systems during postmortem ageing. At 24 h postmortem, beef muscles were packaged respectively in air-permeable film overwrap (AP), vacuum pack (VP) or modified atmosphere (MAP, 80% O 2 + 20% CO 2 ), and then displayed for 10 days at 4 °C., Results: Carbonyl group values and thiol group content were significantly influenced by packaging type and storage time. The SM muscles from AP and MAP showed greater μ-calpain activity compared to VP. Desmin of PM and SM from AP and MAP samples showed decreased proteolysis compared with VP., Conclusion: The results suggested that the inhibition of μ-calpain activity of beef samples from AP and MAP could be closely associated with protein oxidation which further lowered the level of desmin degradation compared to VP. © 2017 Society of Chemical Industry., (© 2017 Society of Chemical Industry.)

The objective of this study was to explore the mechanisms of power ultrasound (PUS, 150 and 300W) and treatment time (30 and 120min) on the water-holding capacity (WHC) and tenderness of beef during curing. Beef muscle at 48h post mortem was subjected to PUS treatment at a frequency of 20kHz. Analysis of compression loss and shear force showed that PUS-assisted curing significantly increased the WHC and the tenderness of beef compared to static brining (p<0.05). According to the analysis of LF-NMR, PUS treatment could increase the P 21 values which indicated an improvement in water-binding ability of beef muscle. SDS-PAGE and LC-ESI-MS/MS analysis suggested that PUS induced moderate oxidation of myosin causing polymerization, which may contribute to increased water retention. On the other hand, an increased tenderness of beef is suggested by the increased MFI values and proteolysis of desmin and troponin-T. Transmission electron microscopy (TEM) further supported the effects of PUS on WHC and tenderness changes due to the swelling and disruption of myofibrils. Thus, these results provide knowledge about the mechanism for improving WHC and tenderness of beef by PUS curing, which could be employed as an emerging technology for various meat curing processes., (Copyright © 2017 Elsevier B.V. All rights reserved.)

This study mainly focused on the purification and identification of antioxidative peptides generated in dry-cured Xuanwei ham. Based on scavenging effect on free radicals and ferrous ion, the antioxidant activity of crude peptides from Xuanwei ham was assessed. From the scavenging effects on 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl (OH) radicals and superoxide anion (O2(-)), it was suggested that XHP generated during the ripening period had a strong antioxidant activity. By using size exclusion chromatography, anion exchange column and reversed-phase HPLC, fractions with a strong antioxidative activity were separated based on their molecular weight and polarity differences. The fraction with strong antioxidant effect was further characterized by LC-MS/MS. The results suggest that antioxidative peptides are produced during the long processing of Xuanwei ham among which the tetrapeptide Asp-Leu-Glu-Glu could be one of the main peptides that play key role in the antioxidant activity., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

This study evaluated the inhibitory effects of spironolac-tone, a non-selective aldosterone receptor antagonist, on hypertension-induced myocardial fibrosis. Collagen I and III contents was detected in the myocardial tissue of spontaneously hypertensive rats (SHRs) after spironolactone administration. Twenty male SHRs were assigned to the spironolactone group or control group (N = 10 each); 7 Wistar-Kyoto rats (WKY) were also used. Spironolactone dissolved in ddH2O was administered via gavage at a dosage of 20 mg·kg(-1)·day(-1). Meanwhile, the control and WKY groups were administered equivalent volumes of ddH2O for 16 weeks. Western blotting was used to detect the contents of collagen I in myocardial tissue; observations were performed using polarizing microscopy, and the area integration and ratio of collagen I/III were subsequently calculated. Compared to the WKY group, col-lagen I synthesis was significantly higher in the control group (1.87 ± 0.2 vs 1.21 ± 0.7, P < 0.05). After 16 weeks of treatment, collagen I contents were significantly lower in the spironolactone group than in the control group (1.42 ± 0.05 vs 1.87 ± 0.2, P < 0.05). The ar-eas of collagen I and collagen I/III ratio were significantly smaller in the spironolactone group than in the control group (6400 ± 259 vs 12,019 ± 734 pixels, 15.64 ± 1.34 vs 20.8 ± 3.04 pixels, respec-tively; P < 0.05). However, there were no significant differences in the area of collagen III among the three groups. In conclusion, spi-ronolactone improves myocardial collagen deposition, preventing myocardial fibrosis in SHRs.

This study was purposed to investigate the effect of bortezomib (Bor) and arsenic trioxide (As(2)O(3)) combination on multiple myeloma cell line KM3 and its mechanisms. KM3 cells were cultured with different concentration of Bor or As(2)O(3) as well as both for a certain time. The cell proliferation was analysed by MTT assay and the concentration of 50% proliferation inhibition (IC(50)) was calculated. Early apoptosis and late apoptosis of KM3 cells were detected by Annexin-V-FITC Kit, and the change of transmembrane potential was measured by flow cytometry. mRNA of Caspase-3, Bim and Bcl-xL were detected by RT-PCR. The results showed that the proliferation inhibitory rate of KM3 cells treated by Bor plus As(2)O(3) was much higher than that of KM3 cells treated by Bor only for 72 h [ (27.64 ± 0.81)% vs (21.67 ± 2.20)%, P < 0.05]. There were more KM3 cells treated by Bor plus As(2)O(3) in early apoptosis at 48 h and late apoptosis at 72 h than that of KM3 cells treated only by Bor [ (53.20 ± 3.70)% vs (35.40 ± 2.58)%, P < 0.01; (63.96 ± 2.97)% vs (54.08 ± 3.76)%, P < 0.01]. Transmembrane potential (Δψm) of KM3 cells treated by Bor plus As(2)O(3) decreased more at 48 h, as compared with Bor alone. The expression levels of caspase-3 mRNA and Bim mRNA in KM3 cells treated with Bor plus As(2)O(3) were higher than that in KM3 cells treated with Bor alone. But the expression level of Bcl-xL mRNA was lower than that in KM3 cells treated with Bor alone. It is concluded that As(2)O(3) can enhance the apoptosis-inducing effect of Bor on multiple myeloma cell line KM3, which is associated with decreasing the expression of Bcl-xl mRNA and increasing the expression of Caspase-3 and Bim mRNA.

Objective: To explore the central mechanisms of anger emotion and the effects of Chinese herbal medicines for regulating liver qi on the anger emotion and the expression level of 5-hydroxytryptamine 3B receptor (5-HT3BR) in rat hypothalamus., Methods: Rat models of anger-in or anger-out emotions were prepared by the methods of resident intruder paradigm. There were five groups in this study: control, anger-in model, Jingqianshu Granule-treated anger-in, anger-out model and Jingqianping Granule-treated anger-out groups. The treatment groups were orally given Jingqianshu granules and Jingqianping granules respectively, and the model groups and the normal control group were given sterile water. Open-field test and sucrose preference test were used to evaluate behavioristics of the rats. Semi-quantitative reverse transcription-polymerase chain reaction and Western blot methods were used to detect the expression levels of 5-HT3BR mRNA and protein in the rat hypothalamus., Results: The expression of 5-HT3BR in hypothalamus of anger-in model rats increased obviously (P<0.01) and that of anger-out model rats decreased obviously (P<0.01) compared with the normal control group. Compared with the model group, the expressions of 5-HT3BR in the treatment groups were significantly improved (P<0.01) after treatment, and recovered to normal level., Conclusion: The anger-in stimulation obviously increases hypothalamic 5-HT3BR expression and the anger-out emotion can obviously reduce its expression. Chinese herbal medicines for regulating liver qi may treat anger emotion in rats by improving the hypothalamic 5-HT3BR protein and gene expression levels.

Thirty-seven (E)-1-(4-methyl-2-arylaminothiazol-5-yl)-3-arylprop-2-en-1-ones were synthesized via Claisen-Schmidt condensation of 1-(4-methyl-2-(arylamino)thiazol-5-yl)ethanone with the corresponding arylaldehydes. All these thiazolyl-chalcones were characterized and evaluated by MTT assay on human cancer cell lines BGC-823, PC-3, NCI-H460, BEL-7402 in vitro. Compounds 5, 8, 26, 37 and 41 are effective against cancer cell lines with IC(50)s below 10 μM. The antitumor activity in ICR mice bearing sarcoma 180 tumors indicates compounds 10 and 41 have moderate in vivo activity with 22-25% tumor-weight inhibition., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

alpha-Lipoic acid derivatives were synthesized and evaluated for their in vitro anticancer activities against NCI-460, HO-8910, KB, BEL-7402, and PC-3 cell lines. The results, for most compounds exhibited dose-dependent inhibitory property and several compounds had good inhibitions at the dose of 100 microg/mL. Compound 17 m was further selected for in vivo evaluation against S180 xenograft in ICR mice, which had 24.7% tumor-weight inhibition through intragastric administration of 200mg/kg of body weight. Moreover, the LD(50) in mice for 17 m through ig exceeded 1000 mg/kg of body weight., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Objective: To determine the effect of cysteinyl receptor agonist leukotriene D(4) (LTD(4)) and its antagonists on rat primary neurons., Methods: In the primarily cultured rat cortical neurons, the neuron injury was evaluated by measuring intracellular calcium, 3-(4, 5-dimethylthiazol-2yl)-2, 5-diphenyl tetrazolium bromide (MTT) reduction, and propidium iodide (PI) and Hoechst 33258 staining. The in vitro ischemic injury was induced by oxygen-glucose deprivation (OGD) for 1.5 h and reperfusion for 24 h., Result: LTD(4) (0.01-1 micromol/L) did not induce the elevation of intracellular calcium, neuron viability changes and neuron death. OGD-induced injury was not significantly ameliorated by the CysLT(1) receptor antagonists, pranlukast (0.2-10 micromol/L) and montelukast (0.2-10 micromol/L), as well as by the CysLT(1)/CysLT(2) receptor non-selective antagonist, BAY u9773 (0.02-1 micromol/L)., Conclusion: Neither agonist nor antagonists of cysteinyl receptors have the effects on the viability and ischemic-like injury in rat primary neurons.

The flavonoid baicalin exerts neuroprotective effects but the mechanism is not fully clarified. On the other hand, 5-lipoxygenase (5-LOX) activation is involved in ischemic neuronal injury. In this study, we determined whether baicalin protects rat cortical neurons against oxygen-glucose deprivation (OGD)-induced ischemic-like injury, if so, whether this effect relates to 5-LOX activation. After the neurons were injured by 1.5-h OGD and 24-h recovery, their viability reduced and necrosis occurred; these injuries were attenuated by baicalin (1 and 5microM) as well as caffeic acid (a 5-LOX inhibitor, 5 and 25microM) and MK-801 (an NMDA receptor antagonist, 1-10microM). OGD-induced 5-LOX translocation to the nuclear envelope as detected by immunoblotting, immunocytochemistry and 5-LOX transfection; this translocation was inhibited by baicalin (5microM) and MK-801 (5microM) but not by caffeic acid (5microM). During 0.5- to 2-h recovery after 1.5-h OGD, the production of 5-LOX metabolites, cysteinyl leukotrienes, was increased; this increased production was inhibited by baicalin and MK-801, while both the increased and baseline production were inhibited by caffeic acid. In addition baicalin and MK-801, not caffeic acid, inhibited glutamate-induced elevation of intracellular calcium. These results indicate that baicalin attenuates ischemic-like injury in the neurons, and this effect partly relates to the inhibition of NMDA receptor-mediated 5-LOX activation.

5-Lipoxygenase (5-LOX) is the enzyme metabolizing arachidonic acid to produce pro-inflammatory leukotrienes. We have reported that 5-LOX is translocated to the nuclear envelope after ischemic-like injury in PC12 cells. In the present study, we determined whether 5-LOX is activated (translocation and production of leukotrienes) after oxygen-glucose deprivation (OGD) in primary rat cortical neurons; if so, whether this activation is mediated by NMDA receptor. After OGD, 5-LOX was translocated to the nuclear envelope as detected by immunoblotting, immunostaining and green fluorescent protein-5-LOX transfection. 5-LOX metabolites, cysteinyl-leukotrienes (CysLTs) but not leukotriene B4, in the culture media were increased 0.5-1.5 h after recovery. Similarly, NMDA (100 microm) also induced 5-LOX translocation, and increased the production of CysLTs during 0.5-1 h NMDA exposure. Both OGD and NMDA reduced neuron viability. NMDA receptor antagonist MK-801 inhibited almost all the responses to OGD and NMDA; whereas 5-LOX activating protein inhibitor MK-886 and 5-LOX inhibitor caffeic acid inhibited the reduction of neuron viability and the production of CysLTs, but did not affect 5-LOX translocation. From these results, we conclude that OGD can activate 5-LOX in primary rat cortical neurons, and that this activation may be partly mediated via activating NMDA receptor.

Recently, we have reported that minocycline, a semi-synthetic tetracycline with neuroprotective effects, inhibits the in vitro ischemic-like injury and 5-lipoxygenase (5-LOX) activation in PC12 cells. In the present study, we further determined whether minocycline protects PC12 cells from excitotoxicity via inhibiting 5-LOX activation. We used N-methyl-d-aspartate (NMDA, 200 microM) to induce early (exposure for 6 h) and delayed (exposure for 6 h followed by 24 h recovery) injuries. We found that NMDA receptor antagonist ketamine, 5-LOX inhibitor caffeic acid and minocycline concentration dependently attenuated NMDA-induced early and delayed cell injuries (viability reduction and cell death). However, only ketamine (1 microM) inhibited NMDA-evoked elevation of intracellular calcium. In addition, immunohistochemical analysis showed that NMDA induced 5-LOX translocation to the nuclear membrane after 1- to 6-h exposure which was confirmed by Western blotting, indicating that 5-LOX was activated. Ketamine, caffeic acid and minocycline (each at 1 microM) inhibited 5-LOX translocation after early injury. After delayed injury, PC12 cells were shrunk, and 5-LOX was translocated to the nuclei and nuclear membrane; ketamine, caffeic acid and minocycline inhibited both cell shrinking and 5-LOX translocation. As a control, 12-LOX inhibitor baicalein showed a weak effect on cell viability and death, but no effect on 5-LOX translocation. Therefore, we conclude that the protective effect of minocycline on NMDA-induced injury is partly mediated by inhibiting 5-LOX activation.

Objective: To determine whether homeostatic conditions (pH, glycine or ion concentration) affect the protective effects of edaravone on ischemic injury in rat cortical neurons., Methods: In cultured rat cortical neurons, the compositions in the experimental solutions were changed to mimic the disturbance of homeostasis after cerebral ischemia. In vitro ischemic injury was induced by oxygen-glucose deprivation (OGD) for 3 h and reperfusion for 12 h, and the neuron injury was evaluated by 3-(4, 5-dimethylthiazol-2yl)-2, 5-diphenyl tetrazolium bromide (MTT) reduction assay and lactate dehydrogenase (LDH) release. Effect of edaravone on OGD injury was observed in different experimental solutions., Result: In weak alkalified solution (pH 7.8) or the solution containing glycine (10 micromol/L), OGD injury became more serious; but in weak acidic (pH 6.5) or higher Mg(2+) (1.8 mmol/L) solutions, OGD injury was attenuated. Edaravone (1 micromol/L) reversed the injury in the solutions with pH 6.1,7.4 and 7.8 or the solution containing glycine, but did not show protective effect in the solution with pH 6.5 and the higher Mg(2+) or lower Ca(2+) solution., Conclusion: The changes of homeostatic conditions affect the severity of ischemic injury of neurons and the protective effect of edaravone.

Aim: To determine the distribution of cysteinyl leukotriene receptor 2 (CysLT2), one of the cysteinyl leukotriene receptors, in human brains with traumatic injury and tumors., Methods: Brain specimens were obtained from patients who underwent brain surgery. CysLT2 in brain tissues was examined using immunohistochemical analysis., Results: CysLT2 was expressed in the smooth muscle cells (not in the endothelial cells) of arteries and veins. CysLT2 was also expressed in the granulocytes in both vessels and in the brain parenchyma. In addition, CysLT2 was detected in neuron- and glial-appearing cells in either the late stages of traumatic injury or in the area surrounding the tumors. Microvessels regenerated 8 d after trauma and CysLT2 expression was recorded in their endothelial cells., Conclusion: CysLT2 is distributed in vascular smooth muscle cells and granulocytes, and brain trauma and tumor can induce its expression in vascular endothelial cells and in a number of other cells.

Objective: To determine the protective effect of monosialoganglionside (GM1) and evaluate the influence of GM1 on expression of N-methyl-D-aspartate receptor subunit 1 (NMDAR1) in Sprague-Dawley (SD) rats with focal cerebral ischemia-reperfusion (I/R)., Methods: Left middle cerebral artery (MCA) was occluded by an intraluminal suture for 1 h and the brain was reperfused for 72 h in SD rats when infarct volume was measured, GM1 (10 mg/kg) was given ip (intraperitoneally) at 5 min (group A), 1 h (group B) and 2 h (group C) after MCA occlusion (MCAo). Expression of NMDAR1 was detected by Western blot at various time after reperfusion (4 h, 6 h, 24 h, 48 h and 72 h) in ischemic hemispheres of the rats with or without GM1 administered., Results: (1) Adjusted relative infarct volumes of groups A and B were significantly smaller than that of group C and the control group (P<0.01 and P<0.05, respectively). (2) Expression level of NMDAR1 was temporally high at 6 h after reperfusion, and dipped below the normal level at 72 h after reperfusion. GM1 at 5 min after MCAo significantly suppressed the expression of NMDAR1 at 6 h after reperfusion (P<0.05 vs the control). At 72 h after reperfusion, the NMDAR1 expression level of rats treated with GM1 administered (at 5 min or 2 h after MCAo) was significantly higher than that of the control (P<0.05)., Conclusion: GM1 can time-dependently reduce infarct volume in rats with focal cerebral I/R partly through stabilizing the expression of NMDAR1.

Aim: To determine direct protective effect of monosialoganglioside (GM1) on hippocampal slices after oxygen-glucose deprivation and reperfusion (OGD/RP), and investigate the influence on the expression of N-methyl-D-aspartate receptor subunit 1 (NMDAR1) in those hippocampal slices., Methods: Injury of hippocampal slices and protective effects of GM1 were detected by 2,3,5-triphenyltetrazolium chloride (TTC) staining, toluidine blue staining, and transmission electron microscopy of rat hippocampal slices. Expression of NMDAR1 was detected by Western blot., Results: (1) GM1 at 1.0 micromol/L was the most effective concentration to preserve the TTC staining of the hippocampal slices after OGD/RP (P<0.05), and the next was GM1 at 10.0 micromol/L (P<0.05). (2) Toluidine blue staining and transmission electron microscopy showed GM1 protected the injuried hippocamal slices after OGD/RP. (3) GM1 downregulated the temporally high expression of NMDAR1 in the hippocampal slices immediately after a 25-min OGD and prevented the over low expression of NMDAR1 after a 30-min reperfusion., Conclusion: GM1 could protect injuried rat hippocampal slices after OGD/RP through stabilizing the expression of NMDAR1.

Objective: To determine the effect of histamine on N-methyl-D-aspartate (NMDA) induced neuron death and to elucidate its mechanism., Methods: The primary cortical cell culture was adopted. Neuron morphology and MTT assay were used to evaluate the drugs effects., Result: Histamine at doses of 10(-4) 10(-6) 10(-7) 10(-8) mol/L reversed the neuron death induced by NMDA (50 micromol/L) for 3 h. The protection of histamine peaked at doses of 10(-4) mol/L and 10(-7)mol/L. The effect of histamine of 10(-7) mol/L was reversed only by cimetidine an H(2)receptor antagonist. However, the effect of histamine of 10(-4) mol/L was reversed only by pyrilamine but not cimetidine., Conclusion: Histamine could reduce neuron death induced by NMDA; its protection at a low dose might be mediated by H(2)receptor, and at a high dose by H(1)receptor.

Objective: To establish a simpler and more accurate method for evaluating in vitro ischemic injury and neuroprotective effects of drugs through improving experimental instrument and quantitative index in mouse brain slices., Methods: An incubation instrument was developed and its application tested. 2,3,5-triphenyltetrazolium chloride (TTC) was used as a substrate to biosynthesize formazan standard in mouse brain slices, and formazan was isolated, purified and identified. Ischemic injury of mouse brain slices was induced by oxygen/glucose deprivation (OGD), the produced formazan from TTC in the cortex and striatum was measured at 490 nm spectrophotometrically. Edaravone and ONO-1078 were added into the incubation medium to observe their neuroprotective effects., Result: The incubation instrument worked well for incubating brain slices and obtaining stable results efficiently. Standard formazan was biosynthesized and purified with a purity of 99.3%, and showed a linear range of 0.05 - 1 mg/ml in absorbance at 490 nm (r=0.9997). OGD decreased formazan production in the cortex and striatum in a duration-dependent manner. Edaravone (0.01 to 1 micromol/L) recovered OGD-induced decrease of formazan production, but ONO-1078 showed no effect., Conclusion: The incubation instrument and quantitative measurement of formazan developed in this study are efficient,accurate and simple for evaluating ischemic injury and neuroprotection,which can be used in screening of neuroprotective drugs in vitro.

Aim: To investigate the protective effect of monosialoganglioside (GM1) on injury induced by oxygen glucose deprivation/reperfusion (OGD/Rep) in rat hippocampal slices., Methods: The protective effects of GM1 on hippocampal slices after OGD/Rep were observed by detecting the light transmittance (LT) changes of rat hippocampal slices and 2, 3, 5-triphenyltetrazolium chloride (TTC) staining of rat hippocampal slices., Results: (1) In four groups treated with 0 (control), 0.1, 1.0, 10 micromol/L GM1, the peak of light transmittance (LT) in the slices treated with 1.0 micromol/L GM1 was significantly lower than that of the control and the group treated with 0.10 micromol/L GM1 (P < 0.01, ANOVA), while the peak of LT in the slices treated with 10.0 micromol/L GM1 was significantly lower than that of the other groups (P < 0.01, ANOVA). The time to reach the peak of LT in four groups was significantly different from each other (P < 0.05, Kruskal-Wallis test). The time to reach the peak of LT in the group treated with 1 micromol/L GM1 was the significantly longer than that in the control (P < 0.01, Mann-Whitney U test). (2) There was characteristic dose-response relationship between GM1 and TTC staining of rat hippocampal slices. In the five groups, treated with 0 (control), 0.01, 0.1, 1.0, 10 micromol/L GM1 respectively, TTC staining in the group treated with 1 micromol/L GM1 was the deepest (P < 0.05 vs. control, 0.01 and 0.1 micromol/L GM1 group, ANOVA), and the next was in the group treated with 10 micromol/L GM1 (P < 0.05 vs. control and 0.01 micromol/L GM1 group, ANOVA)., Conclusion: GM1 could protect injury induced by OGD/Rep in rat hippocampal slices effectively in vitro.