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1.
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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不同利用方式下稻田效益的综合评价 总被引:1,自引:0,他引:1
一、引言评价是多目标系统优化和决策的基础。和任何其他农业生态系统一样,稻田生态系统具有多目标、多功能的特点,单项指标难以反映系统的优劣。目前,川东南地区稻田开发利用方式多种多样,但效益评价主要是采用简单的比较分析或粗放的定性描述,尚未形成系统的 相似文献
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R Takayanagi K Ohnaka Y Sakai R Nakao T Yanase M Haji T Inagami H Furuta D F Gou M Nakamuta 《Biochemical and biophysical research communications》1992,183(2):910-916
We isolated a cDNA encoding type-1 angiotensin II receptor from a human liver cDNA library. The cDNA had an open reading frame encoding a protein of 359 amino acid residues with a relative Mr of 41,060. The deduced amino acid sequence of the human angiotensin II (Ang II) receptor was 95.3% and 94.2% identical to those of bovine and rat type-1 Ang II receptors, respectively, and had a significant similarity with the G protein-coupled receptor. The rank order of the binding to the receptor expressed in COS-7 cells was Ang II greater than Ang III greater than Ang I. The expression of the Ang II receptor mRNA was detected in human liver, lung, adrenal and adrenocortical adenomas but not in adrenomedullary tumor, pheochromocytoma, by Northern blot analysis. 相似文献
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研究了蜜蜂对相同颜色和不同颜色目标图对的形状以及颜色的综合识别能力实验过程中,蜜蜂始终处于自由飞行状态.做为刺激目标使用的图对分别有相同颜色不同几何形状、相同颜色不同拓扑结构和不同颜色几何形状三组.主要结果有三点:(1)在相同颜色的条件下,蜜蜂可以分辨出图形的几何形状,并且识别能力与图对的相似程度成反比(2)在刺激图形为环形时,蜜蜂对图形平均亮度敏感;在平均亮度相同的情况下,对环形细节变和尺寸大小不敏感.(3)在不同颜色不同几何形状的刺激条件下.蜜蜂视觉信息加工过程中颜色因素会抑制几何形状因素而起主要作用.这三个结果可以视为深入研究颜色加工通道和几何形状加工通道之间内在关系的基础. 相似文献
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日粮水平对鲇鱼日总代谢,特殊动力作用和活动代谢的影响 总被引:4,自引:0,他引:4
在25℃不同日粮水平(饥饿─4%体重/d)条件下,采用封闭式呼吸仪测定了31尾鲇鱼(体重72.9─133.3g)的日总代谢率,然后,将鱼限制在呼吸室中的限动笼内测定了其中20尾鲇鱼的静止日总代谢率,并计算出了鲇鱼的特殊动力作用(SDA)和活动代谢率。日总代谢率和活动代谢率都随日粮水平的升高呈“V”形变化,分别在约1%和2%体重/d的日粮水平时最低,SDA的能量支出占摄入能量的22.14%。 相似文献
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油菜主序优势及其利用初析 总被引:2,自引:0,他引:2
油菜具有主序优势,主要表现在结角数上,在角粒数、千粒重及品质上也很显著。不同类型其优势强弱不同,白菜型和甘蓝型优势明显,芥菜型几乎不具有优势。在甘蓝型油菜中因品种、密度不同优势差异显著。增加密度可使主序在产量中的比例增加,在5万株/亩时可达73.05%.主序具有结角率高、成熟早等优点,通过选育优势强的品种,适当增加密度,合理调整布局,有望使油菜产量有较大幅度地提高 相似文献