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1.
建立一种同时快速分离测定不同品种、不同部位淫羊藿中双藿苷A、淫羊藿属苷A、朝藿定C、淫羊藿苷、淫羊藿属苷C、意卡瑞苷A和去多甲基羟基淫羊藿素7种异戊烯基黄酮类成分的梯度洗脱方法,其中双藿苷A、意卡瑞苷A和去多甲基羟基淫羊藿素为首次报道其含量测定。实验比较了三种不同的梯度洗脱条件和三种不同的提取分离条件,选出了实验的最佳条件:采用RP-HPLC法,以美国WATERS SUNFIRETM-C18为色谱柱,乙腈-水为流动相,梯度洗脱(乙腈:0 min,20%;10 min,40%;15 min,45%;20 min,60%),流速为1 mL/min,检测波长270 nm,在此条件下,30 m in内所有组分均得到了良好的分离。实验同时考察比较了巫山淫羊藿植株不同药材部位和其它十种不同品种淫羊藿中7种异戊烯基黄酮类成分的分布。结果表明:不同品种淫羊藿中黄酮类成分的含量差异很大,但大部分品种以朝藿定C为主;同一品种巫山淫羊藿不同部位中则双藿苷A和朝藿定C的含量较大(在巫山淫羊藿根中,两者的含量分别为现行质量控制指标淫羊藿苷的20倍和30倍),可见巫山淫羊藿显著不同于其它品种的淫羊藿,朝藿定C在其药用效果中可能比淫羊藿苷扮演着更重要的角色尤其是在根部作为药用时,这也为民间将巫山淫羊藿根作为小黄连使用提供了一定的实验支持。结论:对于品种较多,分布资源较广的淫羊藿药材,作为药用时,应注意品种和药用部位,考察药材的内在质量,不能一概而论。实验所得到的方法能被用做淫羊藿植株中二次代谢产物分布的快速考察、筛选符合要求的淫羊藿原药材和淫羊藿制备药物中的质量考察。  相似文献   

2.
淫羊藿是一种常用的传统中药.黄酮类成分是淫羊藿的主要有效成分,其中淫羊藿苷是含量最高的单体成分,淫羊藿素是淫羊藿苷的代谢产物.最近10余年来,学者对淫羊藿提取物的药理作用进行了许多研究,表明淫羊藿黄酮,尤其是淫羊藿苷及其衍生物,在骨质疏松症、骨关节炎、神经和精神疾病、动脉粥样硬化、哮喘和肺部疾病、炎症性肠病、肾脏疾病、皮肤病、自身免疫性疾病和癌症等多个与慢性炎症有关的疾病模型中显示了良好的抗炎作用.淫羊藿苷及其衍生物发挥抗炎作用的分子机制主要包括降低炎症细胞因子释放和NF-κB信号通路激活,抑制NLRP3/caspase-1/IL-1β、STAT和MAPK介导的信号传导通路,上调Nrf2/ARE/HO-1信号通路以及糖皮质激素受体和雌激素受体下游信号通路等.本文综述了该领域的近期研究进展,提示淫羊藿及其所含的活性化合物具有治疗多种慢性炎症相关疾病的潜力.  相似文献   

3.
采用HPLC测定不同品种淫羊藿黄酮类即淫羊藿苷、朝藿定A、朝藿定B、朝藿定C4种有效成分含量,结合主成分分析对不同品种淫羊藿进行质量分析与评价,并考察淫羊藿对大鼠肾阳虚保护作用.将实验动物随机分为阳虚模型对照组(模型组)、金匮肾气丸干预组(阳性组)、淫羊藿低(125 mg/kg)、中(250 mg/kg)、高(500 ...  相似文献   

4.
淫羊藿作为传统的中药材,具有补肾阳、强筋骨、祛风湿等功效.其主要功能活性成分为黄酮醇苷成分淫羊藿苷、朝藿定A、B、C等.本实验在武汉植物园内的药园和园外园两个不同生长环境下,研究两种不同光照对巫山淫羊藿(Epimedium wushanense T.S.Ying)WY品系和箭叶淫羊藿(Epimedium sagittatum( Sieb.& Zucc.)Maxim.) LT1、HN3品系4种主要活性成分生物合成的影响.结果显示,在药园环境生长的淫羊藿的光合速率要高于园外园生长的淫羊藿,药园生长的箭叶淫羊藿LT1、HN3品系的4种活性成分含量均高于园外园生长的同品系,而巫山淫羊藿WY品系则相反.光合速率对4种活性成分含量的积累有一定影响,与朝藿定A、B和淫羊藿苷含量呈显著正相关,与朝藿定C含量呈显著负相关.文中对光合速率与活性成分积累间的关系进行了讨论,还针对不同的淫羊藿品系提出了相应的栽培建议.  相似文献   

5.
淫羊藿是一种常用的传统中药。黄酮类成分是淫羊藿的主要有效成分,其中淫羊藿苷是含量最高的单体成分,淫羊藿素是淫羊藿苷的代谢产物。最近十余年来,学者对淫羊藿提取物的药理作用进行了许多研究,表明淫羊藿黄酮,尤其是淫羊藿苷及其衍生物,在骨质疏松症、骨关节炎、神经和精神疾病、动脉粥样硬化、哮喘和肺部疾病、炎症性肠病、肾脏疾病、皮肤病、自身免疫性疾病和癌症等多个与慢性炎症有关的疾病模型中显示了良好的抗炎作用。淫羊藿苷及其衍生物发挥抗炎作用的分子机制主要包括降低炎症细胞因子释放和NF-κB信号通路激活,抑制NLRP3/caspase-1/IL-1β、STAT和MAPK介导的信号传导通路,上调Nrf2/ARE/HO-1信号通路以及糖皮质激素受体和雌激素受体下游信号通路等。本文综述了该领域的近期研究进展,提示淫羊藿及其所含的活性化合物具有治疗多种慢性炎症相关疾病的潜力。  相似文献   

6.
淫羊藿苷药理作用的研究进展   总被引:3,自引:0,他引:3  
淫羊藿为中国传统药用植物,淫羊藿苷是淫羊藿中的主要活性成分.现代药理学研究表明淫羊藿苷具有改善心脑血管功能、加强性腺功能、增强机体免疫功能、抑制破骨细胞,促进成骨细胞生长、延缓衰老、抗肿瘤、抗病毒等生理活性.本文就近年来有关淫羊藿苷药理作用的研究进行综述.  相似文献   

7.
孔璐  黎云祥  权秋梅  张林 《应用生态学报》2010,21(10):2517-2522
2009年8月,采用高效液相色谱法和紫外分光光度法测定了唐家河自然保护区次生落叶阔叶林红桦群落(群落Ⅰ)、常绿落叶阔叶混交林细叶青冈群落(群落Ⅱ)和常绿阔叶林油樟群落(群落Ⅲ)下生长的柔毛淫羊藿各器官的总黄酮和淫羊藿苷含量,分析其与土壤因子的关系结果表明:柔毛淫羊藿叶片中总黄酮和淫羊藿苷含量最高、茎中最低;群落Ⅰ的柔毛淫羊藿总黄酮和淫羊藿苷含量[(5.32±0.23)%和(0.47±0.05)%]均显著高于群落Ⅱ[(4.06±0.03)%和(0.32±0.01)%]和群落Ⅲ[(4.15±0.07)%和(0.28±0.09)%];土壤氮含量和pH值对柔毛淫羊藿的总黄酮和淫羊藿苷含量影响较大,柔毛淫羊藿总黄酮和淫羊藿苷含量与土壤全氮和碱解氮呈显著负相关(P<0.05),与土壤pH值呈极显著正相关(P<0.01).土壤较低的氮供应水平和较高的土壤酸度可能使群落Ⅰ柔毛淫羊藿的总黄酮和淫羊藿苷含量增加.  相似文献   

8.
以苗圃中生长的、盛花期时的淫羊藿属(Epimedium)植物叶片为材料,利用高效液相色谱仪测定不同物种叶片中4种药效黄酮苷的含量,同时测量叶片面积、叶片长宽比等参数.统计分析的结果表明,淫羊藿属不同物种的叶片形态与黄酮苷的含量之间存在一定的联系:活性成分含量高的淫羊藿,其叶片面积较小,形状多呈卵形, 叶片革质化程度也较低.  相似文献   

9.
淫羊藿苷是传统中药淫羊藿的主要活性成分。研究显示淫羊藿苷可能是一个潜在的抗老年疾病的药物。本研究旨在探讨淫羊藿苷对MPP~+诱导的MES23.5细胞损伤的保护作用及其可能机制。细胞活力检测结果显示MPP~+可剂量依赖性地损伤MES23.5细胞,降低细胞存活率,淫羊藿苷可以显著抑制MPP~+所诱导的细胞毒性作用。此外,免疫细胞化学和免疫印迹结果显示淫羊藿苷可对抗MPP~+引起的酪氨酸羟化酶(TH)阳性细胞数的减少和蛋白水平的降低。流式细胞术结果显示,淫羊藿苷可以逆转MPP~+所导致的线粒体膜电位的降低。Real-time RT-PCR和Western blot结果显示,淫羊藿苷可逆转MPP~+所导致的Bax基因和蛋白表达水平的上调以及Bcl-2基因和蛋白表达水平的下调;同时,淫羊藿苷也可以抑制MPP~+所诱导的cleaved caspase-3蛋白的表达水平。以上结果提示,淫羊藿苷可明显对抗MPP~+对MES23.5细胞的神经毒性作用,其作用机制可能与抗凋亡有关。  相似文献   

10.
在模拟生理条件下应用荧光光谱学方法分别研究了淫羊藿苷和淫羊藿次苷Ⅰ与牛血清白蛋白(BSA)间的结合作用. 根据荧光强度数据,计算出了结合常数KA,结合位点数n和热力学参数(△G, △H 和△S). 实验结果表明,淫羊藿苷和淫羊藿次苷Ⅰ都能显著猝灭BSA的内源荧光,猝灭机制均为形成基态复合物的单一静态猝灭过程. 不同温度下(17 ℃, 27 ℃, 37 ℃)得到的KA和n值,表明淫羊藿次苷Ⅰ与BSA的结合强于淫羊藿苷. 从得到的热力学参数判断,淫羊藿苷与BSA间的主要作用力是氢键作用和范德华力,而疏水作用和静电引力在淫羊藿次苷Ⅰ与BSA形成复合物过程中起主导作用.而且同步荧光光谱显示,淫羊藿苷和淫羊藿次苷Ⅰ与BSA的结合导致BSA构象发生了变化.  相似文献   

11.
Peroxynitrite Mediates Nitric Oxide–Induced Blood–Brain Barrier Damage   总被引:5,自引:0,他引:5  
Using the in vitro blood-brain barrier (BBB) model ECV304/C6, which consists of cocultures of human umbilical vein endothelial-like cells (ECV304) and rat glioma cells (C6), the role of peroxynitrite (OONO-) in nitric oxide (NO*)-mediated BBB disruption was evaluated. Endothelial cell cultures were exposed to NO* gas, in the presence or absence of the OONO- blocker FeTPPS. Separate exposure to NO* and OONO- resulted in endothelial cell cytotoxicity and a decline in barrier integrity. Unfortunately, FeTPPS induced significant detrimental effects on model BBB integrity at a concentration of 300 microM and above. At 250 microM (the highest concentration usable), FeTPPS displayed a trend toward prevention of NO* elicited perturbation of barrier integrity. Dichlorofluorescein diacetate is oxidized to fluorescent dichlorofluorescein by OONO- but only marginally by NO* or O2*-. We observed large and rapid increases in fluorescence in ECV304 preloaded cells following NO* exposure, which were blocked by FeTPPS. Furthermore, using an antinitrotyrosine antibody we detected the nitration of endothelial cell proteins following NO* exposure and conclude that NO*-mediated BBB dysfunction is predominantly elicited by OONO- and not NO*. Proposed mechanisms of NO*-mediated OONO- elicited barrier dysfunction and damage are discussed.  相似文献   

12.
There is considerable current interest in the neuroprotective effects of flavonoids. This study focuses on the potential for dietary flavonoids, and their known physiologically relevant metabolites, to enter the brain endothelium and cross the blood-brain barrier (BBB) using well-established in vitro models (brain endothelial cell lines and ECV304 monolayers co-cultured with C6 glioma cells). We report that the citrus flavonoids, hesperetin, naringenin and their relevant in vivo metabolites, as well as the dietary anthocyanins and in vivo forms, cyanidin-3-rutinoside and pelargonidin-3-glucoside, are taken up by two brain endothelial cell lines from mouse (b.END5) and rat (RBE4). In both cell types, uptake of hesperetin and naringenin was greatest, increasing significantly with time and as a function of concentration. In support of these observations we report for the first time high apparent permeability (Papp) of the citrus flavonoids, hesperetin and naringenin, across the in vitro BBB model (apical to basolateral) relative to their more polar glucuronidated conjugates, as well as those of epicatechin and its in vivo metabolites, the dietary anthocyanins and to specific phenolic acids derived from colonic biotransformation of flavonoids. The results demonstrate that flavonoids and some metabolites are able to traverse the BBB, and that the potential for permeation is consistent with compound lipophilicity.  相似文献   

13.
The aim of this work was to conduct a comprehensive study about the transport properties of NSAIDs across the blood-brain barrier (BBB) in vitro. Transport studies with celecoxib, diclofenac, ibuprofen, meloxicam, piroxicam and tenoxicam were accomplished across Transwell models based on cell line PBMEC/C1-2, ECV304 or primary rat brain endothelial cells. Single as well as group substance studies were carried out. In group studies substance group compositions, transport medium and serum content were varied, transport inhibitors verapamil and probenecid were added. Resulted permeability coefficients were compared and normalized to internal standards diazepam and carboxyfluorescein. Transport rankings of NSAIDs across each model were obtained. Single substance studies showed similar rankings as corresponding group studies across PBMEC/C1-2 or ECV304 cell layers. Serum content, glioma conditioned medium and inhibitors probenecid and verapamil influenced resulted permeability significantly. Basic differences of transport properties of the investigated NSAIDs were similar comparing all three in vitro BBB models. Different substance combinations in the group studies and addition of probenecid and verapamil suggested that transporter proteins are involved in the transport of every tested NSAID. Results especially underlined the importance of same experimental conditions (transport medium, serum content, species origin, cell line) for proper data comparison.  相似文献   

14.
Ramsohoye  P.V.  Fritz  I.B. 《Neurochemical research》1998,23(12):1545-1551
Factors secreted by C6 glioma cells which induce electrical resistances across endothelial monolayers in an in vitro blood-brain barrier model have been partially characterised for the first time. These transendothelial electrical resistances (TEERs) were only evident when cell-free conditioned medium derived from C6 glioma cells was applied to the basolateral surfaces of confluent ECV304 or ECV304-9 cells which are both human umbilical vein endothelial cell lines (HUVEC). Electrical resistance values as high as 600 ohm. sq cm were obtained with this blood-brain barrier model and ultrafiltration techniques suggest that any factor(s) in the conditioned medium responsible for these TEERs have molecular masses of less than 1000 Da. Enzymic proteolysis and heat treatment carried out on the conditioned medium failed to inhibit its effect on the HUVEC monolayers suggesting that these C6 cell-secreted factors are unlikely to be proteins.  相似文献   

15.
The objectives of this study were to optimize a sensitive high-performance liquid chromatography (HPLC) method for fatty acid (FA) analysis for the quantification of polyunsaturated FAs (PUFAs) in cell lipid extracts and to analyze the lipid and FA patterns of three cell lines used in blood-brain barrier (BBB) models: RBE4, ECV304, and C6. Thin-layer chromatographic analysis revealed differences in the phosphatidylcholine-phosphatidylethanolamine (PC:PE) ratios and the triglyceride (TG) content. The PC:PE ratio was <1 for RBE4 cells but >1 for ECV304 and C6 cells. ECV304 cells displayed up to 9% TG depending on culture time, whereas the other cell lines contained about 1% TG. The percentages of docosahexaenoic acid were 9.4 +/- 1.7% of the unsaturated FAs in RBE4 cells (n = 5; 4 d in culture; 9.9% after 10 d), 8.1 +/- 2.0% in ECV304 cells (n = 11; 10 to 14 d), and 6.7 +/- 0.6% in C6 cells (n = 6; 10 to 14 d) and were close to the published values for rat brain microvascular endothelium. The percentage of arachidonic acid (C20:4) was about half that in vivo. ECV304 cells contained the highest fraction of C20:4, 17.8 +/- 2.2%; RBE4 cells contained 11.6 +/- 2.4%; and C6 cells 15.8 +/- 1.9%. It is concluded that a sensitive HPLC method for FAs is now optimized for the analysis of long-chain PUFAs. The results provide a useful framework for studies on the effects of lipid modulation and give reference information for the development of further BBB models.  相似文献   

16.
Understanding mechanisms associated with flavonoid neuroprotection is complicated by the lack of information on their ability to enter the CNS. This study examined naringenin and quercetin permeability across the blood-brain barrier (BBB), using in vitro (ECV304/C6 coculture) and in situ (rat) models. We report measurable permeabilities (P(app)) for both flavonoids across the in vitro BBB model, consistent with their lipophilicity. Both flavonoids showed measurable in situ BBB permeability. The rates of uptake (K(in)) into the right cerebral hemisphere were 0.145 and 0.019 ml min(-1) g(-1) for naringenin and quercetin, respectively. Quercetin K(in) was comparable to that of colchicine (0.006 ml min(-1) g(-1)), a substrate for P-glycoprotein (P-gp). Preadministration of the P-gp inhibitor PSC833 or GF120918 (10 mg/kg body wt) significantly increased colchicine K(in), but only GF120918 (able to inhibit breast cancer resistance protein, BCRP) affected K(in) for quercetin. Naringenin K(in) was not affected. The influence of efflux transporters on flavonoid permeability at the BBB was further studied using MDCK-MDR1 and immortalized rat brain endothelial cells (RBE4). Colchicine, quercetin, and naringenin all showed measurable accumulation (distribution volume, V(d) (microl/mg protein)) in both cell types. The V(d) for colchicine increased significantly in both cell lines following coincubation with either PSC833 (25 microM) or GF120918 (25 microM). Both inhibitors also caused an increase in naringenin V(d); by contrast only GF120918 coincubation significantly increased quercetin V(d). In conclusion, the results demonstrate that flavonoids are able to traverse the BBB in vivo. However, the permeability of certain flavonoids in vivo is influenced by their lipophilicity and interactions with efflux transporters.  相似文献   

17.
Oxygen tension regulates the maturation of the blood-brain barrier.   总被引:1,自引:0,他引:1  
The oxygen tension during the development of vascular systems influences vascular vessel formation through regulating angiogenesis. We studied the effect of hypoxia/reoxygenation (H/R) to explain its role in concert with astrocytes involvement in the development of the blood-brain barrier (BBB). On the basis of the fact that the disappearance of hypoxic regions and the decreased expression of vascular endothelial growth factor (VEGF) were observed by immunohistochemistry in a development-dependent manner in rat cerebral cortex, we examined the effects of astrocytes on the BBB-like properties of ECV304 cells by exposing astrocytes to H/R. Conditioned medium of reoxygenated astrocytes inhibited [(3)H]thymidine incorporation and tube formation of ECV 304 cells. When astrocytes were exposed to reoxygenation, the expression of VEGF was reduced, whereas the expression of angiopoietin-1 and thrombospondin-1 was enhanced. Moreover, [(3)H]sucrose permeability assay revealed that astrocytes enhance the barrier function of ECV 304 cells in coculture model within 5 h of reoxygenation. Correspondingly, the occludin expression of ECV 304 cells was slightly increased by the conditioned medium of reoxygenated astrocytes. In conclusion, our study suggests that reoxygenation of astrocytes may act as a significant driving force for the maturation of the BBB during brain development through oxygen-regulated gene(s).  相似文献   

18.
Lipids of brain tissue and brain microvascular endothelial cells contain high proportions of long-chain polyunsaturated fatty acids (long PUFAs). The blood-brain barrier (BBB) is formed by the brain endothelial cells under the inductive influence of brain cells, especially perivascular glia, and coculture of endothelial cells and glial cells has been used to examine this induction. The objective of this study was to investigate whether C6 glioma cells are able to influence the lipid composition and shift the fatty acid (FA) patterns of the BBB model cell lines RBE4 and ECV304 toward the in vivo situation. Lipid classes of the three cell lines were analyzed by thin-layer chromatography and lipid FA patterns by high-performance liquid chromatography. Only ECV304 cells showed altered lipid composition in coculture with C6 cells. The fractions of triglycerides and cholesteryl esters (depending on the support filter) were about twice as high in coculture as when the cells were grown alone. Triglyceride fractions reached 13 to 15% of total lipids in coculture. The three cell lines showed an increase in the percentage of long PUFAs with respect to unsaturated FAs, mainly because of an increase in the percentages of arachidonic acid, all cis-7,10,13,16-docosatetraenoic acid, and all cis-7,10,13,16,19-docosapentaenoic acid. It is concluded that glioma C6 cells are able to induce a more in vivo-like FA pattern in BBB cell culture models. However, changes were not significant for the individual PUFAs, and their levels did not reach in vivo values.  相似文献   

19.
Efficient delivery of therapeutics across the neuroprotective blood–brain barrier (BBB) remains a formidable challenge for central nervous system drug development. High‐fidelity in vitro models of the BBB could facilitate effective early screening of drug candidates targeting the brain. In this study, we developed a microfluidic BBB model that is capable of mimicking in vivo BBB characteristics for a prolonged period and allows for reliable in vitro drug permeability studies under recirculating perfusion. We derived brain microvascular endothelial cells (BMECs) from human induced pluripotent stem cells (hiPSCs) and cocultured them with rat primary astrocytes on the two sides of a porous membrane on a pumpless microfluidic platform for up to 10 days. The microfluidic system was designed based on the blood residence time in human brain tissues, allowing for medium recirculation at physiologically relevant perfusion rates with no pumps or external tubing, meanwhile minimizing wall shear stress to test whether shear stress is required for in vivo‐like barrier properties in a microfluidic BBB model. This BBB‐on‐a‐chip model achieved significant barrier integrity as evident by continuous tight junction formation and in vivo‐like values of trans‐endothelial electrical resistance (TEER). The TEER levels peaked above 4000 Ω · cm2 on day 3 on chip and were sustained above 2000 Ω · cm2 up to 10 days, which are the highest sustained TEER values reported in a microfluidic model. We evaluated the capacity of our microfluidic BBB model to be used for drug permeability studies using large molecules (FITC‐dextrans) and model drugs (caffeine, cimetidine, and doxorubicin). Our analyses demonstrated that the permeability coefficients measured using our model were comparable to in vivo values. Our BBB‐on‐a‐chip model closely mimics physiological BBB barrier functions and will be a valuable tool for screening of drug candidates. The residence time‐based design of a microfluidic platform will enable integration with other organ modules to simulate multi‐organ interactions on drug response. Biotechnol. Bioeng. 2017;114: 184–194. © 2016 Wiley Periodicals, Inc.  相似文献   

20.
In multiple sclerosis and in its animal model experimental autoimmune encephalomyelitis (EAE), inflammatory cells migrate across the endothelial blood-brain barrier (BBB) and gain access to the CNS. It is well-established that alpha4 integrins are actively involved in leukocyte recruitment across the BBB during EAE. In contrast, the role of endothelial E- and P-selectin in this process has been a controversial issue. In this study, we demonstrate that P-selectin protein can be detected in meningeal blood vessel endothelial cells in healthy SJL and C57BL/6 mice and on rare parenchymal CNS blood vessels in C57BL/6, but not SJL, mice. During EAE, expression of P-selectin but not E-selectin was found up-regulated on inflamed CNS microvessels surrounded by inflammatory infiltrates irrespective of their meningeal or parenchymal localization with a more prominent immunostaining detected in C57BL/6 as compared with SJL mice. P-selectin immunostaining could be localized to CNS endothelial cells and to CD41-positive platelets adhering to the vessel wall. Despite the presence of P-selectin in wild-type mice, E/P-selectin-deficient SJL and C57BL/6 mice developed clinical EAE indistinguishable from wild-type mice. Absence of E- and P-selectin did neither influence the activation of myelin-specific T cells nor the composition of the cellular infiltrates in the CNS during EAE. Finally, endothelial-specific tetracycline-inducible expression of E-selectin at the BBB in transgenic C57BL/6 mice did not alter the development of EAE. Thus, E- and P-selectin are not required for leukocyte recruitment across the BBB and the development of EAE in C57BL/6 and in SJL mice.  相似文献   

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