Reproduction,genotype identification and evaluation of APP/PS1 transgenic mice / 中国应用生理学杂志

OBJECTIVES@#To identify the genotype of (APP/PS1) transgenic mice and evaluate the changing of cognitive and behavioral fu nctions, provide an effective animal model for the Alzheimer's disease (AD) research.@*METHODS@#Male APP/PS1 transgenic mice mated with female APP/PS1 transgenic mice, and the genotype of their filial mice was identified by PCR. The APP +/PS1 + mice were assigned into AD model group (AD group, =8), and the APP/PS1 mice were assigned into control group (CT group, =8). The Morris water maze test was carried out to detect the capacity of learning and memory of mice. After that, the mice were sacrificed and the brain tissues were sampled and stained by HE and congo red for the pathological examination.@*RESULTS@#①A APP/PS1 genome DNA about 360 bp size was detected. The methods of feeding and breeding were successful to attain APP/PS1 transgenic mice.②Statistical significance was found in the differences of the capacity of learning and memory between 7-month-old APP/PS1 positive mice and negative mice (<0.05).③The results of HE stain showed that the structure and cellular morphology of hippocampus of AD mice were obviously abnormal. The results of congo red stain showed that positive amyloid plaque was observed in brains of AD mice.@*CONCLUSIONS@#APP/PS1 transgenic mice present typical symptoms and behaviors of Alzheimer's disease. The transgenic mouse is an effective tool for the research and prevention of AD.

Cyanidin-3-O-galactoside and blueberry extracts supplementation improves spatial memory and regulates hippocampal ERK expression in senescence-accelerated mice / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate whether the antioxidation and the regulation on the Extracellular Regulated Protein Kinases (ERK) signaling pathway are involved in the protective effects of blueberry on central nervous system.</p><p><b>METHODS</b>30 Senescence-accelerated mice prone 8 (SAMP8) mice were divided into three groups and treated with normal diet, blueberry extracts (200 mg/kg•bw/day) and cyaniding-3-O-galactoside (Cy-3-GAL) (50 mg/kg•bw/day) from blueberry for 8 weeks. 10 SAMR1 mice were set as control group. The capacity of spatial memory was assessed by Passive avoidance task and Morris water maze. Histological analyses on hippocampus were completed. Malondialdehyde (MDA) levels, Superoxide Dismutase (SOD) activity and the expression of ERK were detected.</p><p><b>RESULTS</b>Both Cy-3-GAL and blueberry extracts were shown effective functions to relieve cellular injury, improve hippocampal neurons survival and inhibit the pyramidal cell layer damage. Cy-3-GAL and blueberry extracts also increased SOD activity and reduced MDA content in brain tissues and plasma, and increased hippocampal phosphorylated ERK (p-ERK) expression in SAMP8 mice. Further more, the passive avoidance task test showed that both the latency time and the number of errors were improved by Cy-3-GAL treatment, and the Morris Water Maze test showed significant decreases of latency were detected by Cy-3-GAL and blueberry extracts treatment on day 4.</p><p><b>CONCLUSION</b>Blueberry extracts may reverse the declines of cognitive and behavioral function in the ageing process through several pathways, including enhancing the capacity of antioxidation, altering stress signaling. Cy-3-GAL may be an important active ingredient for these biological effects.</p>

Three-dimensional finite element modeling of whole lumbar spine and its biomechanical analysis / 医用生物力学

Objective To develop an accurate finite element (FE) model of human L1-S1 spine segment for investigating the pathology of annulus fibrosus rupture of L4-5. Methods Based on CT images of a healthy adult, three-dimensional (3D) model of vertebras and intervertebral discs of lumbar L15 and sacral S1 segment was reconstructed by Mimics 10.01 and Geomagic 10.0 software. The 3D model was then imported into Hypermesh for meshing. With adding various ligaments and assigning material properties of all components, the FE model of L1-S1 segment was established to investigate its biomechanical responses under various loading conditions including axial compression, flexion, lateral bending and extension. Results The global stiffness of the model under flexion, lateral bending, extension with 10 N•m load was 0.61, 0.7 and 0.75 N•m/(°), respectively, which was in good agreement with the experimental results. The strain of annulus fibrosus between L4 and L5 was higher under axial compressive force and bending moment；annulus fibrosus showed obviously stress concentration under any of the different loads. Conclusions The stress concentration and higher strain in annulus fibrosus between L4 and L5 could be one of the reasons leading to rupture. The developed 3D FE model of L1~S1 motion segment demonstrated to be effective in reflecting the biomechanical response of spine and could be used for further spine biomechanics study.

Cytoprotective effect of blueberry extracts against oxidative damage of rat hippocampal neurons induced by H2O2 / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the protective effect of blueberry extract (BE, 25% anthocyanins) against oxidative damage in primary cultures of rat hippocampal neurons induced by H2O2.</p><p><b>METHODS</b>Rat hippocampal neurons were randomly assigned to control group, H2O2 group and BE pretreatment groups, BE at six different doses (0.01, 0.1, 1.0, 10.0, 20.0 and 40 microg/ml) and then exposed to 50 micromol/L H2O2 for twenty-four hours. To selecte the most fittest concentration of BE by testing viability of neurons and activity of LDH. Then MDA concentration, SOD activity and neuronal apoptosis were(checked) measured.</p><p><b>RESULTS</b>(1) Compared with H2O2 group, the hippocampal cell viabilities in the 0.1, 1.0 and 10 microg/ml BE groups were significantly increased from 57.44% to 78.42%, 87.71% and 72.40% separately. The activity of LDH in BE groups at varied concentrations (0.1, 1.0 and 10 microg/ml) was significiantly lower than that in H2O2 group. It was found that 1 microg/ml BE had the furthest protective effect against oxidative damage in primary cultures of rat hippocampal neurons induced by H2O2. (2) The concentration of MDA and the rate of neuronal apoptosis of BE group (1 microg/ml) were much lower than H2O2 group, while SOD activity was much higher.</p><p><b>CONCLUSION</b>Proper dose of BE has remarkable protective effect against oxidative stress in primary cultures of rat hippocampal neurons induced by H2O2, the mechanism may be related to decreasing the neuronal apoptosis and enhancing the antioxidation of hippocampal neurons.</p>

Intervention of antioxidant system function of aged rats by giving fruit juices with different antioxidant capacities / 中华预防医学杂志

<p><b>OBJECTIVE</b>To observe the effects of fruit juices with different antioxidant capacity on antioxidant system function of aged rats.</p><p><b>METHODS</b>Thirty Wistar rats were randomly divided into three groups: pomegranate juice and apple juice as two experimental groups, while distilled water as normal control group. They were administrated fruit juices or distilled water respectively by gavage daily for 4 weeks. At the end of experiment, the antioxidant system function was assessed.</p><p><b>RESULTS</b>The aged rats in pomegranate juice group showed significantly higher serum antioxidant capacity (0.90 +/- 0.13) mmol/L than that in control group (0.79 +/- 0.10) mmol/L (P < 0.05). The concentrations of serum carbonyl and oxLDL were decreased significantly in pomegranate juice group as compared to the control group (P < 0.05). The percentage of injured blood lymphocyte DNA and the ratio of tail length/total length were declined significantly in pomegranate juice group (P < 0.05 and P < 0.01 respectively). The apple juice showed no effects except decreased ratio of tail length/total length of injured lymphocyte DNA. There were no changes in concentrations of serum vitamin C, vitamin E, urinary 8-OH-dG excretion and the activities of serum SOD, GSH-Px, CAT among three groups.</p><p><b>CONCLUSIONS</b>The pomegranate juice should possess higher antioxidant capacity and might improve the antioxidant system function of aged rats, while the apple juice is relatively lower in antioxidant capacity and not very effective. The polyphenols in pomegranate juice might be the important functional components.</p>

Protection against hepatic ischemia-reperfusion injury in rats by oral pretreatment with quercetin / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the possible protection provided by oral quercetin pretreatment against hepatic ischemia-reperfusion injury in rats.</p><p><b>METHODS</b>The quercetin (0.13 mmol/kg) was orally administrated in 50 min prior to hepatic ischemia-reperfusion injury. Ascorbic acid was also similarly administered. The hepatic content of quercetin was assayed by high performance liquid chromatography (HPLC). Plasma glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT) activities and malondialdehyde (MDA) concentration were measured as markers of hepatic ischemia-reperfusion injury. Meanwhile, hepatic content of glutathione (GSH), activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and xanthine oxidase (XO), total antioxidant capacity (TAOC), contents of reactive oxygen species (ROS) and MDA, DNA fragmentation were also determined.</p><p><b>RESULTS</b>Hepatic content of quercetin after intragastric administration of quercetin was increased significantly. The increases in plasma GPT, GOT activities and MDA concentration after hepatic ischemia-reperfusion injury were reduced significantly by pretreatment with quercetin. Hepatic content of GSH and activities of SOD, GSH-Px and TAOC were restored remarkably while the ROS and MDA contents were significantly diminished by quercetin pretreatment after ischemia-reperfusion injury. However, quercetin pretreatment did not reduce significantly hepatic XO activity and DNA fragmentation. Ascorbic acid pretreatment had also protective effects against hepatic ischemia-reperfusion injury by restoring hepatic content of GSH, TAOC and diminishing ROS and MDA formation and DNA fragmentation.</p><p><b>CONCLUSION</b>It is indicated that quercetin can protect the liver against ischemia-reperfusion injury after oral pretreatment and the underlying mechanism is associated with improved hepatic antioxidant capacity.</p>