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Objective To explore the protective effects of dipeptidyl peptidase-4 inhibitor (DPP-4I) on AD-like neurodegenerative changes and its mechanism. Methods The human neuroblastoma cell line SH-SY5Y on the logarithmic phase was divided into six groups:control group (CON group, treated with PBS contained 1‰DMSO for 12 h), wortmannin intervention group (W group, treated with 0.03 μmol/L wortmannin for 12 h), DPP-4I intervention group (DPP-4I group, treated with 10μmol/L DPP-4I for 12 h), both DPP-4I and wortmannin intervention group (DPP-4I+W group, pre-treated with 10 μmol/L DPP-4I for 2 h, then 0.03 μmol/L wortmannin for 12 h), DPP-4I, wortmannin and Ex9-39 intervention group (DPP-4I+W+Ex9-39 group, pre-treated with 10μmol/L Ex9-39 for 2 h, then 10μmol/L DPP-4I for 2 h followed by 0.03μmol/L wortmannin for 12 h), and Ex9-39 intervention group (Ex9-39 group, treated with 10μmol/L Ex9-39 for 12 h). MTT assay was used to detect the cell vitality. Western blot assay was used to detect the level of total tau protein (tau-5) and phosphorylated tau at different sites (pSpS199/202, pT231 and pS396), the level of phosphorylated neurofilaments (NF-H, NF-M) and phosphorylation of critical enzyme in PI3K/Akt/GSK-3β signaling pathway. Results (1) The cell vitality decreased, the levels of pSpS199/202, pT231, pS396 and NF-H/M increased significantly in W group than those in CON group. However, comparing with CON group, the above mentioned parameters reversed in DPP-4I group. Comparing with W group, the cell vitality increased and phosphorylated levels of above mentioned indices were decreased in DPP-4I+W group. (2) The cell vitality showed a decline trend while the levels of phosphorylation tau at three different sites and NF-H/M were higher in Ex9-39 group than those in CON group. Comparing with DPP-4I+W group, the results of the phosphorylated levels showed the same changes in DPP-4I+W+Ex9-39 group. (3) Comparing with CON group, the expression levels of phosphorylated PI3K, Akt and GSK3β increased significantly in DPP-4I group, while those decreased in W group. Additionally, the expression levels of phosphorylated PI3K, Akt and GSK3β were significantly increased in DPP-4I+W group than those in W group. Conclusion DPP-4I can enhance the level of GLP-1 and activate PI3K/Akt/GSK-3βinsulin signaling pathway to improve the hyperphosphorylated tau and NFs induced by wortmannin, and to protect AD-like neurodegeneration.
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Objective To investigate the effects of type 2 diabetes on learning and memory of APP/PS1/Tau triple transgenic (3 × Tg) mice of Alzheimer’s disease, and the protective mechanism of liraglutide (LIR) thereof. Methods One month old C57BL/6 mice were set to be control group (WT). One month old 3×Tg mice were divided into control group (Tg), liraglutide group (Tg+LIR), type 2 diabetes group (Tg+T2DM) and liraglutide treatment group (Tg+T2DM+LIR). The model of T2DM was established by feeding the high fat and sugar fodder, and then injecting streptozotocin (STZ) in mice, making sure the fasting blood glucose was more than 7 mmol/L. Then the subcutaneous injection of LIR was administered for 2 months. The values of body weight and fasting blood glucose were detected at age of 5-month. Morris water maze was applied to evaluate the spatial learning and memory ability. Western blotting assay was used to measure the levels of phosphorylated Tau, neurofilament (NFs) and insulin receptor substrates. ELISA was used to detect the human Aβ42 to evaluate the effect of LIR on-amyloid. Results LIR can reduce body weight and blood glucose, can alleviate spatial learning and memory damaging caused by T2DM, and also can improve phosphorylated Tau levels, NFs and insulin receptor substrates caused by T2DM, and finally can reduce the deposition ofβ-amyloid of 3 × Tg mice. Conclusion T2DM can aggravate symptoms of AD in 3×Tg mice, and LIR has a protective effect on it.
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This study is to investigate the protective effect of rosiglitazone (RSG) against learning and memory impairment of APP/PS1/tau transgenic mice. AD mice model was replicated by using 6-month APP/PS1/tau transgenic mice. The learning and memory ability of mice was evaluated by Morris water maze and Western blotting assays was applied to measure the phosphorylation and O-glycosylation of Tau and neurofilaments (NFs) protein. The results demonstrated that RSG could reverse the learning and memory deficits of 3 x Tg mice significantly. It was also found that RSG could suppress the hyperphosphorylation of Tau and NFs protein levels and increase the glycosylation expression of Tau and NFs proteins in 3 x Tg mice brain. Together, RSG ameliorates cognitive impairments of 3 x Tg mice via the alleviation of the hyperphosphorylated Tau and NFs proteins burden in the brain.
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<p><b>OBJECTIVE</b>To search the candidate gene in the development and metastasis of lung adenocarcinoma and shed light on the possible molecular mechanism of the development of lung carcinoma.</p><p><b>METHODS</b>Using methods of cell culture, reverse transcription-PCR, RH gene mapping and RNA in situ hybridization.</p><p><b>RESULTS</b>The cDNA fragment named OPB7-1 was mapped at 1p31-1p34 by RH gene mapping method. The fragment sequences obtained from lung cDNA library of normal person and cell line of AGZY83-a were similar in length but showed individual base difference. For OPB7-1, there is a low homogeneity to known gene by analysis in GenBank, but 3 contigs homologous to OPB7-1 were located at chromosome 1(1p31-1p34). Different degrees of expression were noted in tumor tissues from 24 cases of lung carcinoma, however no significant expression was found in their corresponding normal tissues. And high expression was found in the lung tissues of cases with lymph node metastasis.</p><p><b>CONCLUSION</b>OPB7-1 may be a novel gene. It may be a tumor related gene in occurrence and metastasis of lung carcinoma.</p>
Subject(s)
Animals , Humans , Rats , Adenocarcinoma , Genetics , Chromosome Mapping , Cloning, Molecular , DNA, Complementary , Genetics , Gene Expression Regulation, Neoplastic , Genetic Predisposition to Disease , Genetics , In Situ Hybridization , Lung Neoplasms , Genetics , Pathology , RNA, Neoplasm , Genetics , Metabolism , Radiation Hybrid Mapping , Tumor Cells, CulturedABSTRACT
Objective To study the protective effect on transient focal cerebral ischemic preconditioning against neuronal cell apoptosis again,and the relationship between bcl 2, bax and cerebral ischemic tolerance.Methods Middle cerebral artery occlusion (MCAO) was showed for 20 min by craniotomy and MCA was blocked 6 h after 3 d.Cerebral infarct volume and the change of histopathological in rats were observed,the status of neuronal cell apoptosis were observed by TUNEL mothod,the alteration of bcl 2 and bax protein expression were observed by immunohistochemical method.Results As compared with the false preconditioning group and ischemia group,the infarct volume in the ischemic group reduced significantly after preconditioning( P
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Objective To investigate the protective role of transient focal ischemic precondition(PC) against permanent focal cerebral ischemia, to define the proper time dose for precondition, and to study the reaction of astroglia in cerebral ischemic tolerance. Methods Temporary middle cerebral artery occlusion(10 minutes, 20 minutes, 30 minutes) followed three day reperfusion before permanent middle cerebral artery occlusion(PMCAO) transcranially was used as precondition in Wistar rats. The protective role was evaluated by observing the neurological deficits, analyzing the infarct volume and studying changes of pathohistology. The reaction of astroglia was observed by using anti GFAP immunohistochemistry.Results Compared with the control group, 20 min ischemic precondition, which did not produce neuronal damage obviously, alleviated the neurological deficits and reduced the infarct volume significantly( P
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AIM: To explore the effect of nuclear factor-?B (NF-?B) on the anti-apoptosis induced by brain ischemia preconditioning (IP). METHODS: Temporary middle cerebral artery occlusion for 20 min followed three days reperfusion before 6 hours middle cerebral artery occlusion (MCAO) trancranially was used as preconditioning in Wistar rats. The protective role was evaluated by analyzing the infarct volume. The status of neuronal apoptosis was observed by TUNEL. The expression of NF?B p65 protein, the assay of SOD activity and MDA concentration were analyzed by using the methods of immunohistochemistry and cytochemistry. RESULTS: Compared to the control group, 20 min ischemic preconditioning, which did not produce neuronal damage obviously, reduced the infarct volume significantly after MCAO 6 h and obviously decreased the number of neural cell apoptosis in penumbra (P