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Xiaozhong Huang Yujuan Shi Hongjin Chen Rongrong Le Xiaohua Gong Ke Xu Qihan Zhu Feixia Shen Zimiao Chen Xuemei Gu Xiaojun Chen Xiong Chen 《Cell death & disease》2020,11(12)
Diabetic nephropathy (DN) as a global health concern is closely related to inflammation and oxidation. Isoliquiritigenin (ISL), a natural flavonoid compound, has been demonstrated to inhibit inflammation in macrophages. Herein, we investigated the effect of ISL in protecting against the injury in STZ-induced type 1 DN and in high glucose-induced NRK-52E cells. In this study, it was revealed that the administration of ISL not only ameliorated renal fibrosis and apoptosis, but also induced the deterioration of renal function in diabetic mice. Mediated by MAPKs and Nrf-2 signaling pathways, respectively, upstream inflammatory response and oxidative stress were neutralized by ISL in vitro and in vivo. Moreover, as further revealed by the results of molecular docking, sirtuin 1 (SIRT1) binds to ISL directly, and the involvement of SIRT1 in ISL-mediated renoprotective effects was confirmed by studies using in vitro models of SIRT1 overexpression and knockdown. In summary, by reducing inflammation and oxidative stress, ISL has a significant pharmacological effect on the deterioration of DN. The benefits of ISL are associated with the direct binding to SIRT1, the inhibition of MAPK activation, and the induction of Nrf-2 signaling, suggesting the potential of ISL for DN treatment.Subject terms: Pharmacology, Molecular biology 相似文献
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本文报道笼养和野生白腹锦鸡机体营养成分及其差异。分析表明,笼养的比野生种营养成分含量高的有:腿肌蛋白质高11%,胸肌、腿肌、全血的氨基酸分别高2.64%,1.39%和4.68%,胸肌、腿肌和肝脏的碳水化合物分别高0.076%、0.092%和3.962%,胸肌和腿肌的维生素A分别高188.63和84.09 I.U.,胸肌和腿肌的维生素D分别高47.2和12.8 I.U.。但是胸肌蛋白质含量笼养的比野生的低26%。 相似文献
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The utilization of some amino acids, added at 1 mM and 10 mM concentrations, as the sole combined nitrogen sources by Frankia sp. strain CpI1, has been investigated. Glutamine, like NH
4
+
, provided rapid growth without N2 fixation. Histidine at 1 mM yielded poor N2-fixing activity but better cell growth than N2. Aspartate, glutamate, alanine, proline, each at 1 mM concentration, supported similar levels of N2 fixation and growth. Growth on 10 mM glutamate, proline, or histidine resulted in poor N2-fixing activity and poor cell growth. Cells grown on 10 mM alanine had about half the N2-fixing activity of cells grown on N2 but growth was good. Aspartate at 10 mM concentration, however, stimulated N2-fixing activity dramatically and promoted faster growth. Enzyme analysis suggested that asparate is catabolized by glutamate-oxaloacetate transaminase (GOT), since GOT specific activity was induced, and aspartase activity was not detected, in cells grown on aspartate as the sole combined nitrogen source. Thinlayer chromatography (TLC) of metabolites extracted from N2-grown cells fed with [14C]-aspartate showed that label was rapidly accumulated mainly on aspartate and/or glutamate, depending on the cells' physiological state, without detectable labeling on fumarate or oxaloacetate (OAA). These findings provide evidence that aspartate is catabolized by GOT to OAA which, in turn, is rapidly converted to -ketoglutarate through the TCA cycle and then to glutamate by GOT or by glutamate synthase (GOGAT). The stimulation of N2 fixation and growth by aspartate is probably caused by an increased intracellular glutamate pool. 相似文献
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用组胺H_2受体拮抗剂(甲氰咪胍或呋喃硝胺)处理正常和亚致死量γ-射线照射小鼠,探讨正常体内造血和再生骨髓中造血重建与组胺受体的关系。发现非毒性剂量的甲氰咪胍对正常小鼠骨髓多能造血干细胞(CFU-s)无抑制作用,但可抑制小鼠体内粒单系祖细胞(CFU-GM)的生长和亚致死量照射后CFU-s产率的恢复。组胺可能与骨髓的再生有关,组胺H_2受体拮抗剂可抑制骨髓的造血重建。 相似文献
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两组不同月龄小鼠学习记忆能力与脑突触体内游离[Ca^2+]i的相关性 总被引:10,自引:0,他引:10
本文采用Y-迷宫和一次被动回避反应模型,观察了1,6月龄小鼠的学习记忆行为,并运用Ca~(2+)的荧光探针和AR-CM-MIC阳离子测定系统,检测了两组小鼠四个主要脑区(海马、皮层、小脑、中脑四叠体)突触体内游离钙离子浓度([Ca~(2+)]_i)的变化。结果表明随着年龄的增长,小鼠的分辨学习及记忆能力均下降,同时海马突触体内游离[Ca~(2+)]_i升高显著。 相似文献
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从每公斤萌发24h的玉米胚丙酮粉中可提纯得63mg的钙调素(CaM),这是目前从每公斤植物材料中所提纯得CaM的最高记录。对其理化性质的研究表明,玉米胚CaM 有较高的生物学活性,能较好地激活磷酸二酯酶,其紫色吸收光谱,SDS-PAGE电泳行为及氨基酸组成与其它的植物CaM相似。上述结果表明玉米胚是1个提取植物CaM相似。上述结果表明玉米胚是1个提取植物CaM的适宜材料。 相似文献
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Na2SO3对热-DTT活化的游离CF1及类囊体膜上CF1-ATPase活力均有显著的促进作用,NaHCO3亦有明显的促进作用。Na2SO3和NaHCO3的促进作用与它们解除Mg2+的抑制作用有关。从NaHCO3和Na2SO3及它们与Mg2+之间的竞争性关系,表明三者是结合在酶的同一部位上。Na2SO3可明显降低热-DTT活化的游禹CF1-ATPase催化反应的活化能,这可能与促进产物ADP的释放有关。 相似文献
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MethodsforHandy,RapidIsolationofHighQualityRNAbyGuanadiumThioeyauateDuJianYuanYanhuaMaShenglinDongZhiwei(BeijingInstituteforCancerResearchBeijing100034)硫氰胍是一种有效的蛋白变性剂。早在1979年,Chirgwin等就利用氯化铯/硫氰胍超离心技术成功地从RNA酶富集的胰脏组织中提取出未降解的RNA分子[2],从而使它成为抑制RNA酶的首选药物并得到广泛使用,但受到超速离心设备的限制。1983年,Cathala报道了氯化锂/硫氰胍RNA提取法[1]。该方法操作简便,获得的RNA质量很高,但所需时间较长。为了能在短时间内更快… 相似文献