槲皮素对SMMC-7721肝癌细胞PI3K/AKT信号通路影响的探讨

目的:观察槲皮素( quercetin)对人肝癌细胞SMMC-7721增殖与细胞凋亡的影响,探讨其对SMMC-7721细胞PI3K/AKT信号通路的影响.方法:采用MTT法检测槲皮素对SMMC-7721细胞生长的抑制,流式细胞术检测细胞周期变化,Western blot检测槲皮素对SMMC-7721细胞PI3K/AKT信号通路凋亡相关蛋白表达的影响.结果:槲皮素抑制SMMC-7721肝癌细胞增殖作用明显,且呈浓度和时间依赖性.顺铂和槲皮素40,80,160,320 μmol·L-148 h抑制率分别为62.19％,25.47％,27.18％,36.96％,51.28％.流式细胞术结果提示,槲皮素80,160,320μmol ·L -可使SMMC-7721肝癌细胞周期阻滞于G0/G1期.Western blot凋亡相关蛋白表达检测表明,药物组AKT的表达受抑制,PTEN,Caspase-9蛋白的表达率随着药物浓度的增加而增加.结论:槲皮素能诱导SMMC-7721肝癌细胞凋亡,其机制可能是使肝癌细胞SMMC-7721周期阻滞于G0/G1期,PTEN的过表达抑制AKT活化,激活Caspase-9从而促进细胞凋亡.     

槲皮素对人骨肉瘤细胞U-2OS/MTX300增殖和凋亡的影响及其机制研究

目的:研究槲皮素(quercetin,Qu)对骨肉瘤细胞系U-2OS/MTX300增殖和凋亡的作用及其机制。方法:MTT法观察细胞增殖活性;Annexin V/PI染色检测凋亡;线粒体膜电位及细胞色素C的Western blot检测线粒体凋亡途径;持续活化Akt瞬时转染、Western blot检测Akt通路相关蛋白表达水平变化。结果:槲皮素可明显抑制耐甲氨蝶呤骨肉瘤细胞U-2OS/MTX300生长,并呈时间和剂量依赖性;Annexin V/PI可明显检测到细胞凋亡;进一步发现其作用机制是通过下调线粒体膜电位,促进细胞色素C向胞浆释放及抑制Akt磷酸化来实现。结论:槲皮素可显著抑制耐甲氨蝶呤骨肉瘤细胞系U-2OS/MTX300细胞增殖并诱导其凋亡,其机制与线粒体凋亡途径及抑制Akt活性有关。     

基于指纹图谱及化学模式识别研究盐制对五子衍宗丸化学成分的影响

目的 建立不同炮制品组方五子衍宗丸(Wuzi Yanzong Pills,WYP)的HPLC指纹图谱,研究盐制对WYP化学成分的影响.方法 采用HPLC法建立不同炮制品组方WYP的指纹图谱,并进行相似度评价,采用方差分析、聚类分析(CA)、主成分分析(PCA)与偏最小二乘法-判别分析(PLS-DA)对结果进行评价.结果...     

HPLC法测定傣药雅路哈中槲皮素的含量

目的:建立傣药雅路哈(接骨1号)中槲皮素的含量测定方法。方法:采用高效液相色谱法,C18色谱柱(4.6mm×200mm,5μm);流动相:甲醇-0.4%磷酸溶液(52∶48);检测波长:360nm;流速:1.0mL/min;柱温:30℃。结果:槲皮素在10.56～528μg范围内线性关系良好(r=0.9999),回收率98.21%,RSD为l.87%。结论:为傣药雅路哈(接骨1号)质量标准的研究,提供准确、可靠的方法。     

载槲皮素-粉防己碱纳米凝胶的制备、表征与体外评价

[目的]制备一种纳米凝胶制剂以提高槲皮素及粉防己碱的生物利用度及抗氧化性。[方法]通过反相乳化法制备载槲皮素-粉防己碱纳米凝胶(QU-TE-NP);通过粒径与Zeta电位测定,透射电子显微镜(TEM),差示扫描量热分析(DSC)以及傅里叶变换红外光谱(FT-IR)进行表征分析;高效液相法测定两种药物的载药率及包封率;1,1-二苯基-2-三硝基苯肼(DPPH)清除实验比较槲皮素及该纳米凝胶的体外抗氧化性。[结果]该纳米凝胶通过钙离子交联,平均粒径为(38.86±1.81)nm,Zeta电位为(-15.9±4.1)m V,槲皮素和粉防己碱的载药率分别为(0.98±0.04)%和(2.75±0.07)%,包封率分别为(96.80±1.10)%和(94.80±0.90)%。纳米凝胶的抗氧化性明显优于槲皮素单体。[结论]纳米凝胶体系的制备可提高槲皮素及粉防己碱的水溶性,并增强其抗氧化能力。     

六种僵蚕炮制品的薄层鉴别与含量测定研究

目的:考察不同炮制方法对僵蚕中草酸铵、槲皮素和山奈酚的含量影响。方法:采用薄层色谱法对僵蚕6种炮制品进行薄层鉴别研究;采用高效液相色谱法测定各炮制品中草酸铵、槲皮素和山奈酚的含量。结果:僵蚕各炮制品的薄层色谱未见明显差异,但僵蚕经过炮制后体内草酸铵含量都有不同程度的下降。其中糖麸炒僵蚕的含量最低,而麸炒僵蚕中草酸铵含量下降的最少。僵蚕经过炮制后所含槲皮素与山奈酚的含量变化不大,与生品较为接近,但姜炙僵蚕与姜麸炒僵蚕中槲皮素与山奈酚的含量降低得较为明显。结论:不同炮制方法对僵蚕的化学成分含量有一定程度的影响,但影响幅度不尽相同。并且,不同的炮制方法功效各异,各有所长。为提高临床疗效和便于患者服用,可根据需要对其炮制方法灵活选择。     

基于网络药理学及实验验证探究清热利胆汤治疗胆汁瘀积性肝损伤的作用机制

目的 基于网络药理学及实验验证探究清热利胆汤治疗胆汁瘀积性肝损伤的作用机制.方法 采用网络药理学方法筛选清热利胆汤和胆汁瘀积性肝损伤相关的核心靶点,构建基于活性成分与疾病共同靶点的蛋白质-蛋白质相互作用(protein-protein interaction,PPI)网络,利用DAVID数据库对潜在作用靶点进行京都基因...     

A New Asymmetric ent-Kauranoid Dimer from Rabdosia rubescens

Objective To study the ent-kaurane diterpenoids from Rabdosia rubescens. Methods The compounds were isolated by chromatographies and their structures were identified by spectral analyses. Results Four compounds were isolated, and they were identified as bisrubescensin E (1), 2α,3α,24-trihydroxyurs-12-en-28-oic acid (2), 2α,3α,24-trihydroxyurs-12,20-(30)-dien-28-oic acid (3), and 6,7-dihydroxycoumarin (4). Conclusion Compound 1 is a new asymmetric ent-kauranoid dimer. Compound 2 is isolated from the plant for the first time. Compounds 3 and 4 are isolated from the plants of Rabdosia (Bl.) Hassk for the first time.     

Is quercetin an alternative natural crosslinking agent to genipin for long‐term dermal scaffolds implantation?

As biocompatible matrices, porcine dermal scaffolds have limited application in tissue engineering due to rapid degradation following implantation. This study compared the physical, chemical and biomechanical changes that occurred when genipin and quercetin were used to crosslink dermal scaffolds and to determine whether quercetin could be used as an alternative to genipin. Physicochemical changes in the collagen were assessed using spectroscopic methods [X‐ray diffraction analysis (XRD) and nuclear magnetic resonance (NMR) analysis]. The crosslinking reaction was evaluated by quantification of amino acids and the degree of this reaction by ninhydrin assay. Because the mechanical behaviour of the collagen matrices is highly influenced by crosslinking, the tensile strength of both sets of scaffolds was evaluated. The highest mechanical strength, stiffness, degree of crosslinking and changes in the packing features of collagen (measured by XRD) were achieved using genipin. Some of the results found in the quercetin‐crosslinked scaffolds were possibly due to hydration and dehydration effects elicited by the solvents (phosphate‐buffered saline or ethanol), as seen in the NMR results. In the quercetin‐ethanol‐crosslinked scaffolds, possible reorientation of the amino groups of the collagen molecule may have taken place. Therefore, depending on their proximity to the crosslinking reagent, different types and numbers of interactions may have occurred, inducing a higher crosslinking degree (as evidenced by the ninhydrin assay) and reduction in the free amino acids after reaction. Both crosslinking agents and solvents interfere in the physicochemical properties of collagen thereby inducing variations in the matrix structure. Quercetin‐crosslinked scaffolds may have broader clinical application where a lower degree of crosslinking and stiffness is required. Copyright © 2016 John Wiley & Sons, Ltd.     

在非水介质中用表面引发接枝聚合法制备接枝微粒PHEMA-SiO2及其对槲皮素的氢键吸附性能

首先,将偶联剂γ-巯丙基三甲氧基硅烷(MPMS)上的巯基(-SH)键合在微米级硅胶(SiO₂)微粒表面,得到了改性微粒MPMS-SiO₂。在非水溶剂N,N-二甲基甲酰胺(DMF)中,使溶液中的过氧化苯甲酰(BPO)与改性微粒MPMS-SiO₂表面的巯基构成表面引发体系(-SH/BPO),于非水介质中在硅胶微粒表面实现了甲基丙烯酸羟乙酯(HEMA)的接枝聚合,成功制备出接枝微粒PHEMA-SiO₂,接枝度高达28 g/100 g。采用红外光谱(FT-IR)、热重分析(TG)及扫描电子显微镜(SEM)等手段对PHEMA-SiO₂进行了表征,研究了主要因素对HEMA表面引发接枝聚合的影响规律。在此基础上探索研究了PHEMA-SiO₂对槲皮素(Quercetin)的氢键吸附作用。研究结果表明:-SH/BPO引发体系可以顺利地引发HEMA在非水介质中的接枝聚合,适宜的温度为65℃,适宜的BPO用量为单体质量的1.0%。PHEMA-SiO₂与槲皮素分子之间会产生多位点普通氢键与π型氢键两种氢键相互作用,使PHEMA-SiO₂对槲皮素具有强吸附能力。溶剂分子对槲皮素的竞争吸附以及温度的升高均可使槲皮素在极性溶剂或质子性溶剂中吸附容量下降。