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范梦月  刘静  孙蓉 《中草药》2020,51(9):2297-2306
目的筛选藿朴夏苓汤治疗早期新型冠状病毒肺炎(COVID-19)湿邪郁肺证的物质基础,预测其作用机制。方法查阅文献及临床报道分析藿朴夏苓汤与早期COVID-19湿邪郁肺证的方证关系。运用TCMSP数据库筛选藿朴夏苓汤中潜在活性成分,将活性成分与新型冠状病毒(SARS-CoV-2)3CL水解酶、血管紧张素转化酶Ⅱ(ACE2)进行分子对接,根据结合能筛选与两者均有较好结合作用的核心成分。借助Cytoscape软件构建关键成分靶点蛋白互作网络,筛选出核心靶点;通过STRING数据库进行核心靶点的GO分析,Cytoscape软件Clue GO插件进行Pathway、KEGG富集分析。结果方证关系分析藿朴夏苓汤用于治疗早期COVID-19湿邪郁肺证,筛选出藿朴夏苓汤中潜在作用成分12个,核心靶点67个。其中通草中的通脱木皂苷元Ⅰ,茯苓、猪苓中的过氧麦角甾醇,半夏中的黄芩苷与SARS-CoV-2 3CL水解酶、ACE2均具有较好的结合活性。GO、Pathway、KEGG富集分析结果显示藿朴夏苓汤中12个潜在作用成分参与调节刺激反应、信号转导、细胞死亡等生物过程以及白介素信号通路、癌症EGFR信号通路、酪氨酸激酶信号转导途径、编程性细胞死亡途径、MAPK信号通路等。结论藿朴夏苓汤以化湿解毒、宣肺透邪治疗早期COVID-19湿邪郁肺证患者,菲酮、黄芩苷、酸枣仁皂苷、啤酒甾醇、常春藤皂苷元、过氧麦角甾醇、柠檬二烯醇、麦角甾-7,22-二烯-3-酮、通脱木皂苷元Ⅰ、泽泻醇B-23-醋酸酯、泽泻醇B、新橙皮苷可能为其主要的物质基础,通过阻断SARS-CoV-2病毒蛋白合成,阻止病毒进入宿主细胞,通过调控白介素信号通路、MAPK信号通路、PI3K-Akt信号通路、T细胞受体信号通路、C型凝集素受体信号通路,抑制相关炎症因子的表达发挥作用。  相似文献   
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In this comprehensive evidence-based analysis of ulcerative colitis (UC), a causal role is identified for colonic epithelial hydrogen peroxide (H2O2) in both the pathogenesis and relapse of this debilitating inflammatory bowel disease. Studies have shown that H2O2 production is significantly increased in the non-inflamed colonic epithelium of individuals with UC. H2O2 is a powerful neutrophilic chemotactic agent that can diffuse through colonic epithelial cell membranes creating an interstitial chemotactic molecular “trail” that attracts adjacent intravascular neutrophils into the colonic epithelium leading to mucosal inflammation and UC. A novel therapy aimed at removing the inappropriate H2O2 mediated chemotactic signal has been highly effective in achieving complete histologic resolution of colitis in patients experiencing refractory disease with at least one (biopsy-proven) histologic remission lasting 14 years to date. The evidence implies that therapeutic intervention to prevent the re-establishment of a pathologic H2O2 mediated chemotactic signaling gradient will indefinitely preclude neutrophilic migration into the colonic epithelium constituting a functional cure for this disease. Cumulative data indicate that individuals with UC have normal immune systems and current treatment guidelines calling for the suppression of the immune response based on the belief that UC is caused by an underlying immune dysfunction are not supported by the evidence and may cause serious adverse effects. It is the aim of this paper to present experimental and clinical evidence that identifies H2O2 produced by the colonic epithelium as the causal agent in the pathogenesis of UC. A detailed explanation of a novel therapeutic intervention to normalize colonic H2O2, its rationale, components, and formulation is also provided.  相似文献   
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It is widely accepted that redox reprogramming participates in malignant transformation of lung adenocarcinoma (LUAD). However, the source of excessive reactive oxygen species (ROS) and the downstream signaling regulatory mechanism are complicated and unintelligible. In the current study, we newly identified the aquaporin 3 (AQP3) as a LUAD oncogenic factor with capacity to transport exogenous hydrogen peroxide (H2O2) and increase intracellular ROS levels. Subsequently, we demonstrated that AQP3 was necessary for the facilitated diffusion of exogenous H2O2 in LUAD cells and that the AQP3-dependent transport of H2O2 accelerated cell growth and inhibited rapamycin-induced autophagy. Mechanistically, AQP3-mediated H2O2 uptake increased intracellular ROS levels to inactivate PTEN and activate the AKT/mTOR pathway to subsequently inhibit autophagy and promote proliferation in LUAD cells. Finally, we suggested that AQP3 depletion retarded subcutaneous tumorigenesis in vivo and simultaneously decreased ROS levels and promoted autophagy. These findings underscore the importance of AQP3-induced oxidative stress in malignant transformation and suggest a therapeutic target for LUAD.  相似文献   
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目的:完善金水宝胶囊生产过程中的质量控制体系,为该制剂的后续研究与应用提供实验依据。方法:采用高效液相色谱法(HPLC),Ultimate AQ-C18色谱柱(4.6 mm×150 mm,5μm),腺苷、鸟苷、尿苷含量测定的色谱条件为流动相甲醇(A)-0.1%甲酸水溶液(B)梯度洗脱(0~14 min,100%~99%B;14~19 min,99%~89%B;19~39 min,89%~85%B),流速0.4 m L·min^-1,柱温30℃,进样量10μL,检测波长260 nm。麦角甾醇含量测定的色谱条件为流动相甲醇-水(98∶2),流速1 m L·min^-1,柱温25℃,进样量10μL,检测波长283 nm。结果:发酵虫草菌粉不同生产阶段样品的指纹图谱中主要色谱峰差异性较小。腺苷、鸟苷、尿苷的线性关系良好(R2均>0.999);三者的加样回收率分别为106.06%,101.25%,105.88%,RSD均<3.0%。于2016-2018年各抽取的20批样品中腺苷、麦角甾醇的含量均符合2015年版《中国药典》的要求,鸟苷、尿苷的质量分别为0.97~1.36,0.67~1.38 mg/粒。结论:市面所售金水宝胶囊质量较为稳定。建立的方法可用于检测金水宝胶囊的质量,且操作简便、稳定可靠,可为发酵虫草菌粉类产品的检测提供参考。  相似文献   
6.
【摘要】 目的 研究Fe3O4纳米酶对白念珠菌的抗菌作用。方法 改进水热合成法,制备Fe3O4纳米酶。以0.5 g/L Fe3O4纳米酶和0.1% H2O2与菌液共培养,分为纳米酶组、H2O2组、联合组(纳米酶 + H2O2共处理),以未做处理菌液为对照组。4组菌液以沙氏液体培养基培养,每隔2 h检测600 nm处吸光度(A值),观察白念珠菌生长情况。取4组菌液共处理2 h,扫描电镜观察各组白念珠菌形态;涂板后,于36 ℃培养48 h,观察菌落形成情况并计数,计算抑菌率。多组间均数比较采用单因素方差分析,组间两两比较采用LSD-t检验。结果 对照组白念珠菌具有相对稳定的生存曲线,而纳米酶组、H2O2组、联合组白念珠菌的生长均受到抑制。4组菌落计数分别为124 830 ± 45 170、86 330 ± 13 960、91 670 ± 31 370、30 330 ± 3010,差异有统计学意义(F = 9.41,P < 0.05),联合组低于对照组(t = 4.63,P < 0.05)。H2O2组、纳米酶组、联合组抑菌率分别为30.84% ± 5.00%、26.57% ± 11.24%、75.70% ± 2.42%,差异有统计学意义(F = 9.413,P < 0.01),联合组高于H2O2组、纳米酶组(t = 8.08、4.27,P < 0.01),差异均有统计学意义。扫描电镜观察,经过处理后菌体形态发生皱缩、破裂甚至崩解等改变。结论 Fe3O4纳米酶联合H2O2对白念珠菌抑菌效果明显。  相似文献   
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Hericium novae-zealandiae is a native mushroom consumed by indigenous Māori people in New Zealand. The lipophilic mycochemicals of the mushroom were isolated using a normal column chromatography combined with a preparative HPLC. Structural characterisation based on spectroscopic methods, namely UV, MS, NMR and single crystal XRD have identified three lipophilic compounds as hericene B (a compound unique to Hericium), ergosterol and ergosterol peroxide. Following this, an HPLC-DAD method was developed and validated to quantify the hericene B and ergosterol. The method showed excellent selectivity, linearity, precision, accuracy and robustness. The content of hericene B was determined as 28.53 mg/g by dry weight of H. novae-zealandiae (approximately 3%). This discovery indicates the potential utilisation of H. novae-zealandiae as a natural source of hericene B. Current research revealed for the first time, the lipophilic constituents of H. novae-zealandiae and the method development for quantification of hericene B in the above species.  相似文献   
9.
Gold nanoparticles (AuNPs) have been previously shown to induce gut dysbiosis during colitis in mice, but the underlying mechanism is not clear yet. Here, we evaluated the effects of AuNPs (5?nm diameter, coated with tannic acid, polyvinylpyrrolidone or citrate) on H2O2 accumulation and pathogen antagonization by an intestinal strain of Lactobacillus gasseri under aerobic cultural conditions. AuNPs (0.65?μg/mL) reduced over 50% of H2O2 accumulation by L. gasseri, and significantly inhibited the antagonistic action of L. gasseri on growth of four foodborne enteric pathogens, i.e. Salmonella enterica serovar Typhimurium, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus in associative cultures.  相似文献   
10.
Relatively young (4-week-old) selenium deficient (SeD) mice, which lack the activity of selenium-dependent glutathione peroxidase (GSH-Px) isomers, were prepared using torula yeast-based SeD diet. Mice were fed the torula yeast-based SeD diet and ultra-pure water. Several different timings for starting the SeD diet were assessed. The weekly time course of liver comprehensive GSH-Px activity after weaning was monitored. Protein expression levels of GPx1 and 4 in the liver were measured by Western blot analysis. Gene expression levels of GPx1, 2, 3, 4, and 7 in the liver were measured by quantitative real-time PCR. Apoptotic activity of thymocytes after hydrogen peroxide (H2O2) exposure was compared. Thirty-day survival rates after whole-body X-ray irradiation were estimated. Pre-birth or right-after-birth starting of the SeD diet in dams was unable to lead to creation of SeD mice due to neonatal death. This suggests that Se is necessary for normal birth and healthy growing of mouse pups. Starting the mother on the SeD diet from 2 weeks after giving birth (SeD-trial-2w group) resulted in a usable SeD mouse model. The liver GSH-Px activity of the SeD-trial-2w group was almost none from 4 week olds, but the mice survived for more than 63 weeks. Protein and gene expression of GPx1 was suppressed in the SeD-trial-2w group, but that of GPx4 was not. The thymocytes of the SeD-trial-2w group were sensitive to H2O2-induced apoptosis. The SeD-trial-2w group was sensitive to whole-body X-ray irradiation compared with control mice. The SeD-trial-2w model may be a useful animal model for H2O2/hydroperoxide-induced oxidative stress.  相似文献   
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