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151.
Increasing evidence shows that oxidative stress and the hyperphosphorylation of tau protein play essential roles in the progression of Alzheimer’s disease (AD). Quercetin is a major flavonoid that has anti-oxidant, anti-cancer and anti-inflammatory properties. We investigated the neuroprotective effects of quercetin to HT22 cells (a cell line from mouse hippocampal neurons). We found that Okadaic acid (OA) induced the hyperphosphorylation of tau protein at Ser199, Ser396, Thr205, and Thr231 and produced oxidative stress to the HT22 cells. The oxidative stress suppressed the cell viability and decreased the levels of lactate dehydrogenase (LDH), superoxide dismutase (SOD), mitochondria membrane potential (MMP) and Glutathione peroxidase (GSH-Px). It up-regulated malondialdehyde (MDA) production and intracellular reactive oxygen species (ROS). In addition, phosphoinositide 3 kinase/protein kinase B/Glycogen synthase kinase3β (PI3K/Akt/GSK3β) and mitogen activated protein kinase (MAPK) were also involved in this process. We found that pre-treatment with quercetin can inhibited OA-induced the hyperphosphorylation of tau protein and oxidative stress. Moreover, pre-treatment with quercetin not only inhibited OA-induced apoptosis via the reduction of Bax, and up-regulation of cleaved caspase 3, but also via the inhibition of PI3K/Akt/GSK3β, MAPKs and activation of NF-κB p65. Our findings suggest the therapeutic potential of quercetin to treat AD. 相似文献
152.
153.
大口鲇和鲇鱼血清蛋白质及同工酶的比较研究 总被引:10,自引:0,他引:10
采用聚丙烯酰胺梯度凝胶垂直板电泳,分析了大口鲇和鲇鱼的血清蛋白质以及心脏、肝脏、眼和肌肉4种组织的EST及MDH同工酶。结果表明,大口鲇和鲇鱼的血清蛋白质均能分离出20条左右的谱带,两者既表现出相同的谱带,又表现出迁移率和含量都不同的带型。两者的EST和MDH同工酶在4种组织及血清中均能特异性地表达,存在明显的组织和物种特异性。本文认为肝脏是研究大口鲇和鲇鱼种群生化遗传结构与变异的理想材料,同时还探讨了两种鲇鱼的M DH同工酶位点。
Abstract:The serum proteins and isozymes in four tissues (heart,liver,eye and musele)of Smeridionalis Chen and S.asotus Linnaeus were analyzed by polyacrylamide gradient gel vertical electrophoresis.The isozymes are esterase(EST)and malate dehytrogenase(MDH).The results showed that electrophoretograme of serum proteins were about 20 protein pattens in two species catfish,they were either the same protein pattens or the different pattens.Electrophoretogram of isozymes(EST,MDH)in two species catfish indicated tissues and species specificity.Experiment considered that the liver was a good material studied biochemical genetic constitution and variation in species group of S.meridionalis Chen and S.asotus Linnaeus. 相似文献
154.
Uncaria rhynchophylla (Gouteng) is a famous traditional Chinese medicine used for psychiatric and hypotensive purposes in China. In this study, the ethyl acetate (EtOAc) part of U. rhynchophylla was revealed with protein tyrosine phosphatase 1B (PTP1B) inhibitory activity. Subsequent investigation on the EtOAc part yielded one new triterpenoid, 3β-formyloxy-6β,19α-dihydroxyurs-12-en-28-oic acid (1) and four known ones, 3β,6β,19α-trihydroxyurs-12-en-28-oic acid (2), 2-oxopomolic acid (3), 3β,19α-dihydroxy-6-oxo-olean-12-en-28-oic acid (4) and sumaresinolic acid (5). The structure of compound 1 was determined by extensive HRESIMS, IR, 1D and 2D NMR spectroscopic analyses. Two ursane-type triterpenoids (2 and 3) showed selective inhibition on PTP1B with IC50 values of 48.2 and 178.7 μM. The enzyme kinetic study suggested that compounds 2 and 3 were mix-type inhibitors on PTP1B with Ki values of 15.6 and 132.5 μM. This investigation manifests the antidiabetic potency of U. rhynchophylla with triterpenoids as the active constituents. 相似文献
155.
Yuan Zhang Chunjie Li Xianliang Ke Dan Luo Yan Liu Quanjiao Chen Hanzhong Wang Xiaohui Song Zhenhua Zheng 《中国病毒学》2022,37(3):459-461
Highlights:
The biosensor reported in our study can monitor SARS-CoV-2 Mpro activity in living cells instead of in vitro solutions.
The biosensor reported in our study is sensitive and easy to operate.
It is suitable for high-throughput screening.
It has the potential to be used in small animal models. 相似文献
The biosensor reported in our study can monitor SARS-CoV-2 Mpro activity in living cells instead of in vitro solutions.
The biosensor reported in our study is sensitive and easy to operate.
It is suitable for high-throughput screening.
It has the potential to be used in small animal models. 相似文献
156.
157.
Xi Tian Wen-Hao Xu Aihetaimujiang Anwaier Hong-Kai Wang Fang-Ning Wan Da-Long Cao Wen-Jie Luo Guo-Hai Shi Yuan-Yuan Qu Hai-Liang Zhang Ding-Wei Ye 《Journal of cellular and molecular medicine》2021,25(8):3898-3911
This study aims to construct a robust prognostic model for adult adrenocortical carcinoma (ACC) by large-scale multiomics analysis and real-world data. The RPPA data, gene expression profiles and clinical information of adult ACC patients were obtained from The Cancer Proteome Atlas (TCPA), Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA). Integrated prognosis-related proteins (IPRPs) model was constructed. Immunohistochemistry was used to validate the prognostic value of the IPRPs model in Fudan University Shanghai Cancer Center (FUSCC) cohort. 76 ACC cases from TCGA and 22 ACC cases from GSE10927 in NCBI’s GEO database with full data for clinical information and gene expression were utilized to validate the effectiveness of the IPRPs model. Higher FASN (P = .039), FIBRONECTIN (P < .001), TFRC (P < .001), TSC1 (P < .001) expression indicated significantly worse overall survival for adult ACC patients. Risk assessment suggested significantly a strong predictive capacity of IPRPs model for poor overall survival (P < .05). IPRPs model showed a little stronger ability for predicting prognosis than Ki-67 protein in FUSCC cohort (P = .003, HR = 3.947; P = .005, HR = 3.787). In external validation of IPRPs model using gene expression data, IPRPs model showed strong ability for predicting prognosis in TCGA cohort (P = .005, HR = 3.061) and it exhibited best ability for predicting prognosis in GSE10927 cohort (P = .0898, HR = 2.318). This research constructed IPRPs model for predicting adult ACC patients’ prognosis using proteomic data, gene expression data and real-world data and this prognostic model showed stronger predictive value than other biomarkers (Ki-67, Beta-catenin, etc) in multi-cohorts. 相似文献
158.
Objective: Long non-coding RNAs (lncRNAs) recently have been identified as influential indicators in a variety of malignancies. The aim of the present study was to identify a functional lncRNA LINC00488 and its effects on thyroid cancer in the view of cell proliferation and apoptosis.Methods: In order to evaluate the effects of LINC00488 on the cellular process of thyroid cancer, we performed a series of in vitro experiments, including cell counting kit-8 (CCK-8) assay, EdU (5-ethynyl-2′-deoxyuridine) assay, flow cytometry, transwell chamber assay, Western blot and RT-qPCR. The target gene of LINC00488 was then identified by bioinformatics analysis (DIANA and TargetScan). Finally, a series of rescue experiments was conducted to validate the effect of LINC00488 and its target genes on proliferation, migration, invasion and apoptosis of thyroid cancer.Results: Our findings revealed that LINC00488 was highly expressed in thyroid cancer cell lines (BCPAP, BHP5-16, TPC-1 and CGTH-W3) and promoted the proliferation, migration and invasion, while inhibited the apoptosis of thyroid cancer cells (BCPAP and TPC-1). The results of bioinformatics analysis and dual luciferase reporter gene assay showed that LINC00488 could directly bind to miR-376a-3p and down-regulated the expression level of miR-376a-3p. In addition, Paraoxonase-2 (PON2) was a target gene of miR-376a-3p and negatively regulated by miR-376a-3p. Rescue experiment indicated that LINC00488 might enhance PON2 expression by sponging miR-376a-3p in thyroid cancer.Conclusion: Taken together, our study revealed that lncRNA LINC00488 acted as an oncogenic gene in the progression of thyroid cancer via regulating miR-376a-3p/PON2 axis, which indicated that LINC00488-miR-376a-3p-PON2 axis could serve as novel biomarkers or potential targets for the treatment of thyroid cancer. 相似文献
159.
Song Wang Quan Quan Cheng Meng Weinan Chen Yiqi Luo Shuli Niu 《Journal of Plant Ecology》2021,14(3):541
增温对高寒草甸生态系统碳氮循环耦合关系的影响
陆地生态系统碳吸收受土壤氮素可用性的调节。然而,全球变化背景下的不同生态系统组分的碳氮比及其所反映的碳氮循环耦合关系尚不十分清楚。本文运用数据同化的方法,将一个高寒草甸增温试验的14组数据同化到草地生态系统模型中,从而评估了增温如何影响陆地生态系统的碳氮循环耦合关系。研究结果表明,增温提高了土壤氮素的有效性,降低了土壤活性碳库的碳氮比,导致植物对土壤氮的吸收增加。但是由于植物叶片吸收的碳比吸收的氮增加更多,使得叶片中碳氮比增加,而根部的碳输入增加则低于氮的增加,导致根部的碳氮比减少。同时,增温降低了凋落物碳氮比,可能是在土壤高氮有效性的条件下,凋落物氮的固定得到增强;而且增温加速了凋落物的分解。同时增温还增加了慢速土壤有机质的碳氮比,使得该土壤碳库的碳固存潜力增大。由于大多数模型在不同的环境中通常使用相对固定的碳氮比,本研究所发现的气候变暖条件下碳氮比的差异变化可为模型参数化提供一个有效的参考,有利于模型对未来气候变化背景下生态系统碳氮耦合关系响应的预测。 相似文献
160.
Mingzhu Luo Rong Fan Xiaoming Wang Junyu Lu Ping Li Wenbin Chu Yonghe Hu Xuewei Chen 《Bioscience reports》2021,41(6)
Ethnopharmacological relevance: Gualou Xiebai Banxia (GLXBBX) decoction is a well-known traditional Chinese herbal formula that was first discussed in the Synopsis of the Golden Chamber by Zhang Zhongjing in the Eastern Han Dynasty. In traditional Chinese medicine, GLXBBX is commonly prescribed to treat cardiovascular diseases, such as coronary heart disease and atherosclerosis.Objective: The present study aimed to examine GLXBBX’s preventative capacity and elucidate the potential molecular mechanism of Poloxamer 407 (P407)-induced hyperlipidemia in rats.Materials and methods: Both the control and model groups received pure water, and the test group also received a GLXBBX decoction. For each administration, 3 ml of the solution was administered orally. To establish hyperlipidemia, a solution mixed with 0.25 g/kg P407 dissolved in 0.9% normal saline was injected slowly into the abdominal cavity. At the end of the study, the rats’ plasma lipid levels were calculated using an automatic biochemical analyzer to evaluate the preventative capability of the GLXBBX decoction, and the serum and liver of the rats were collected.Results: The GLXBBX decoction significantly improved P407-induced hyperlipidemia, including increased plasma triglycerides (TGs), aspartate aminotransferase (AST) elevation, and lipid accumulation. Moreover, GLXBBX decoction treatment increased lipoprotein lipase (LPL) activity and mRNA expression of LPL. Furthermore, GLXBBX significantly suppressed the mRNA expression of stearoyl-CoA desaturase (SCD1).Conclusion: GLXBBX significantly improved P407-induced hyperlipidemia, which may have been related to enhanced LPL activity, increased LPL mRNA expression, and decreased mRNA expression of SCD1. 相似文献