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1.
<正> 本文结合肝素和类肝素的结构,对其生物活性和临床应用进行综述。这类药物的化学组成是酸性粘多糖,所以首先对粘多糖的有关问题,作一介绍。一、粘多糖的结构与生物活性1938年Meyer提出把动物来源含有氨基己糖(己糖胺)的多糖称为粘多糖。根据此化学组成,可称粘多糖为糖胺多糖。在天然状态下的氨基己糖,常常在氨基上有乙酰基和硫酸基(磺酸基)取代的情况。近来,所谓粘多糖多  相似文献   

2.
氨基多糖的药理研究进展   总被引:18,自引:0,他引:18  
沈鸣  陈建伟 《上海医药》2001,22(6):268-270
多糖按照来源可分为植物多糖、动物多糖、菌多糖等。目前已证明许多植物多糖具有广泛的生物活性。随着多糖研究的进一步发展和对动物类药材的日益重视,对动物多糖的研究也逐渐增多。 动物多糖主要有糖原、甲壳素、肝素、硫酸软骨素以及透明质酸等,在结构上由氨基己糖和糖醛酸构成重复单元的称酸性粘多糖。酸性粘多糖除上述肝素、硫酸软骨素和透明质酸外还有硫酸角质素和硫酸类肝素,在体内,酸性粘多糖常以蛋白质结合状态存在,且糖的含量高于蛋白质,所以这类物质统称为蛋白多糖。 1 药理活性 1.1 抗癌、提高免疫力 多糖抗癌的原因大多是激活了体内免疫系统,改善了机体免疫力。据报道,文蛤多糖100和200mg/kg能显著抑制小鼠S_(180)实体瘤重,显著延长EAC腹水瘤荷瘤小鼠的生存时间,并且对环磷酰胺造成的免疫功能损伤有改善作  相似文献   

3.
<正> 前言肝素、硫酸软膏素、透明质酸等粘多糖是一类生化药物,在它们的多糖结构中含有-CO_2~-基,有的含有-SO_3~-基,因其酸性较强,故称为酸性粘多糖。这类粘多糖基本上由特定的重复双糖单位构成,在此双糖单位中,糖醛酸多为葡萄糖醛酸和艾杜糖醛酸;氨基糖则多为氨基葡萄糖和氨基半乳糖。它们因其组成中所含单糖的种类、比例、N-乙酰基、N-  相似文献   

4.
葡聚糖广泛分布于高等植物、地衣、海藻、动物和微生物中。微生物来源的葡聚糖是至今研究得比较详细的一类多糖,其中关注最多的是beta葡聚糖,其广泛的生物活性使得其成为微生物药物的一类重要组成部分,在新药研发中受到越来越多的重视。本文对迄今为止国内外所发现的葡聚糖的药用生物活性及其临床应用进行了综述。  相似文献   

5.
<正> 一、前言肝素、硫酸软骨素、透明质酸等酸性粘多糖,是一类有效的生化药物。在它们的多糖结构中含有CO_2~-基,有的含有一SO_3~-基,因此是一类多聚阴离子物质。根据这类物质的所带电荷量的不同,它们在电场中迁移率有所差异,从而达到分离测定的目的。利用醋酸纤维素薄膜电泳分离这类酸性粘多糖,在一定程度上与这类多聚物的聚合量无关,使这类酸性粘多糖  相似文献   

6.
猪肠粘膜中性粘多糖的研制   总被引:1,自引:0,他引:1  
多糖是一类重要的生物高分子,有些是具有临床疗效的生化药物。目前国内外用于治疗冠心病的粘多糖有Ateroid~[1,2],Ves  相似文献   

7.
3.粘多粮分解酶如上文所述,粘多糖有很多种类,在动物组织中完成重要功能的同时和动物的健康状况也有密切关系,因此,关于粘多糖分解酶的研究及对这些多糖的分析,在代谢途径的研究上占有重要位置,进而才能应用于医药和食品加工等方面。本文汇集了这些酶的存在,研究方法和应用实例。 3.1 粘多糖分解酶的存在和性质  相似文献   

8.
我们成功的从海洋棘皮门动物花刺参中提取了花刺参粘多糖[1],其主要含有己糖醛酸、岩藻糖、半乳糖、氨基己糖等单糖.我们以往的研究工作证实,复方花刺参粘多糖具有明显降低大鼠血清总胆固醇和甘油三酯、降低血浆血栓素B2和前列腺素E2水平、升高6-酮-前列腺素F1α水平、降低血浆中纤维蛋白原含量以及抑制血小板聚集的作用,是降血脂、抗凝血、防血栓形成的有效药物[2].因此,本研究在此基础上,进一步探讨复方花刺参粘多糖对成形术后血管内皮功能的保护作用及其作用机制.  相似文献   

9.
<正> 肝素钠本质上是分子量不同的粘多糖相混合在一起的硫酸氨基多糖的钠盐。肝素存在于哺乳动物组织中,通常从肠粘膜中或其它被人们食用的一些适当的组织中提取。肝素是由D-葡糖胺的衍生物(N-硫酸或N-乙酰)和糖醛酸(L-艾杜糖醛酸或D-葡萄糖醛酸)通过糖苷键交替组成的多聚物。在肝素彻底水解时,这些成份以不同的比例重新释放出来。肝素具有多种生物活性,其主要活性是延长凝血时间。肝素通过和血浆中抗凝血酶形成复合物,从而使凝血酶失活,并且也抑制其它凝血蛋白  相似文献   

10.
<正> 肝素系动物体内存在的一种酸性粘多糖。1916年Mclean在研究凝血机制时,偶然发现人体内存在一种抗凝血的物质。1918年Howell从狗肝粉中提取了这种物质,当时认为动物肝脏中这种物质最多,就命名为“肝素”。许多学者相继提出了许多制备方法。1935年用于临床。1943年Hahn发现肝素不但有抗凝血性质,还有澄清血脂的作用。1950年Jorpes证实,肝素分子中氨基已糖残基上存在磺氨基,并认为这是区别于其它多糖的最显著的特点之一。多年来人们对生命的基本物质-蛋白质、  相似文献   

11.
Urinary levels of glycosaminoglycans (GAG) and hydroxyproline from normal and fluoride treated rabbits were estimated. The hydroxylysine content of serum and urine of rabbits after excessive ingestion of fluoride was also investigated. There was a progressive decrease in GAG content, reduction in hydroxylysine, whereas the hydroxyproline content was increased after fluoride ingestion. Enhanced hydroxyproline in urinary excretion is due to collagen breakdown after fluoride ingestion. The reduction in hydroxylysine content is due to reduced collagen cross-link formation. The report suggests the possibility of using the urinary levels of GAG or hydroxyproline or hydroxylysine as an index of fluoride intoxication.  相似文献   

12.
邢军  刘赛  王海桃  亓翠菊 《中国药房》2008,19(19):1459-1461
目的:研究扇贝裙边糖胺聚糖(SS-GAG)的体外抗肿瘤活性及对荷瘤小鼠的抗氧化功能的影响。方法:用MTT法观察不同浓度的SS-GAG对体外培养的宫颈癌HeLa、人大肠癌LOVO、肺癌A549、神经胶质瘤U251等肿瘤细胞株增殖活性的影响;观察SS-GAG对小鼠接种S180后30d内的存活时间;通过黄嘌呤氧化酶法、硫代巴比妥酸显色法等多种生化方法观察SS-GAG对荷瘤小鼠血清总抗氧化能力(T-AOC)、超氧化物岐化酶(SOD)活性和丙二醛(MDA)含量的影响,并与对照比较。结果:与对照比较,SS-GAG可明显抑制HeLa、U251细胞生长,对LOVO、A549细胞生长也有一定的抑制作用;SS-GAG能显著延长S180腹水瘤小鼠的生存时间,提高荷瘤小鼠的T-AOC、SOD水平,降低MDA含量(P<0.01或P<0.05)。结论:SS-GAG可抑制肿瘤生长,并有一定的抗氧化作用。  相似文献   

13.
The extracellular matrix (ECM) plays a significant role in the structure and function of the lung. The ECM is a three-dimensional fibre mesh, comprised of various interconnected and intercalated macromolecules, among which are the glycosaminoglycans (GAG). GAG are long, linear and highly charged, heterogeneous polysaccharides that are composed of a variable number of repeating disaccharide units (macromolecular sugars) and most of them, as their name implies, have a sweet taste. In the lung, GAG support the structure of the interstitium, the subepithelial tissue and the bronchial walls, and are secreted in the airway secretions. Besides maintaining lung tissue structure, GAG also play an important role in lung function as they regulate hydration and water homeostasis, modulate the inflammatory response and influence lung tissue repair and remodelling. However, depending on their size and/or degree of sulphation, and their immobilization or solubilization in the ECM, specific GAG in the lung either live up to their sweet taste/name, supporting normal lung physiology, or they are associated to ‘bitter’ effects, related to lung pathology. The present review discusses the biological role of GAG in the lung as well as the involvement of these molecules in various respiratory diseases. Given the great structural diversity of GAG, understanding the changes in GAG expression that occur in lung diseases may lead to novel targets for pharmacological intervention in order to prevent and/or to treat a range of lung diseases.  相似文献   

14.
The glycosaminoglycan (GAG) distribution pattern of murine fetal tibiae cultured for 6 days in vitro was determined and the effects of drugs on the growth of the tibia explants in vitro, on their total GAG content and on their GAG distribution pattern were studied. The explants contained chondroitin-4-sulfate and chondroitin-6-sulfate in a relation of about 4:1; hyaluronic acid was not detected. During the incubation period of 6 days in vitro a mean increase in size of 47% and of the total GAG content of about 80-90% was observed; the GAG distribution pattern was practically unchanged. Incubation of the explants in a medium without ascorbic acid by contrast to a medium containing ascorbic acid (5 and 50 micrograms/ml) lead to a reduction of growth and total GAG content. The nonsteroidal antiphlogistic drugs phenylbutazone (20 and 200 micrograms/ml), ibuprofen (25 and 200 micrograms/ml) and alclofenac (25 and 400 micrograms/ml) effected a concentration dependent decrease of the growth and of the GAG content of the explants mainly due to a reduction of chondroitin-4-sulfate. Prednisolone (10 micrograms/ml) caused a significant increase of the GAG content of the explants leaving their GAG distribution pattern nearly unchanged. Aurothioglucose (400 micrograms/ml) induced a reduction of the growth and of the GAG content of the explants without altering the GAG distribution. Under low concentrations of Na-pentosanpolysulfate (5 micrograms/ml) an increase in growth and in the GAG content by a nearly unaltered GAG distribution pattern was observed, high concentrations (200 micrograms/ml), however, caused a reduction of growth and of the GAG content.  相似文献   

15.
气相色谱法鉴别扇贝糖胺聚糖的中性糖基   总被引:3,自引:1,他引:2  
从海湾扇贝中提取分离出糖胺聚糖,分子中除含有氨基己糖和己糖醛酸外,还含有中性糖基。样品经盐酸-甲醇试剂醇解成单糖,用六甲基二硅胺烷和三甲基硅烷硅醚化成三甲基硅醚衍生物,于气相色谱仪中测定,并与标准单糖比较分析,结果发现,扇贝糖胺聚糖含有5种中性糖基,即葡萄糖,半乳糖,木糖,岩藻糖和鼠李糖。  相似文献   

16.
Glycosaminoglycans were investigated in surgically removed human liver and kidney tumours by applying biochemical methods. Four liver adenoma, 6 focal nodular hyperplasia and 9 primary hepatocellular carcinoma samples were compared with normal liver from autopsy cases and also with liver tissue adjacent to PHC. The studies on kidney included 14 renal cell carcinoma and 4 wilms' tumour samples. Three findings emerged from the quantitative and qualitative characterization of the tumours with epithelial origin. 1) The rise in the amount of total GAG was not limited to the malignant lesion. Similar increase was observed in benign liver tumours and also in the tissue adjacent to liver or kidney malignant tumours. 2) The dominant type of the GAG subclasses varies with the histology of the tumours. In benign liver tumours dermatan sulfate, in PHC and renal cell carcinoma chondroitin sulfate, but in Wilms' tumour hyaluronate was the prominent GAG subclass. 3) In all tumour-affected tissues dermatan and chondroitin sulfates had lower degree of sulfation. However, in the histologically different tumours various disaccharides showed reduced level of sulfation. The GAG alteration in renal cell carcinoma was compared with the prognostic factors of each individual case. This analysis showed a good correlation between HS/CS ratio and the prognostic factors of the kidney tumour cases.  相似文献   

17.
Diftalone showed a distinct inhibition effect on the collagen formation in sponge granuloma as well as in chick embryos articular cartilage. The inhibitory effect was expressed even in corneal and articular cartilage glycosaminoglycans (GAG) sulphation and GAG formation in granulation tissue. According to our previous results diftalone showed a similar inhibition of collagen and GAG biosynthesis as other effective antirheumatic drugs.  相似文献   

18.
SRY基因序列分析8例   总被引:5,自引:0,他引:5  
为寻找性反转及生殖器发育不良患者的病因,对8例患者在染色体核型分析的基础上,利用PCR扩增技术对患者的SRY基因进行检测和序列分析。结果:8例患者的SRY基因全部存在;DNA序列分析发现1例46,XX女性伴SRY基因存在的患者在HMG盒内有点突变,即codon112G→C。1例46,XY女性性反转综合征患者有移码突变和点突变并存。为患者从分子基础上找到了病因,并为研究性反转及生殖器发育不良提供了科学的有价值的资料。  相似文献   

19.
Summary Teratogenic doses of vitamin A or of Na-salicylate have been found to alter the distribution of 35S labelled GAG after fractionation on an anionic exchanger (ECTEOLA-Cellulose). The results are interpreted as a loss of the anionic properties of GAG.-Tracer studies with 35S on embryonic tissue are complicated by the fact that the embryotoxic substances used in these experiments alter the rate of 35S elimination from the maternal blood and thereby change the specific activity of the GAG precursors in the embryonic cells when compared with the radioactivity available in control embryos. Under these experimental conditions the rate of 35S incorporation into GAG does therefore not give a direct measure of GAG biosynthesis. In the studies the results of which are presented in this paper this difficulty has been overcome by calculating the relative rate of 35S incorporation into different GAG fractions of the embryonic tissue.After treatment with teratogenic substances, 35S labelled GAG are found to appear in the low anionic fraction which contains nearly no 35S activity in control embryos.This work was generously supported by grants from the Deutsche Forschungsgemeinschaft given to the Sonderforschungsbereich 29 Embryonale Entwicklung und Differenzierung (Embryonal-Pharmakologie).  相似文献   

20.
T Kaji  C Yamamoto  M Sakamoto 《Toxicology》1991,68(3):249-257
We investigated the effect of lead nitrate (0.1, 1.0, 10 or 20 microM) on the metabolism of glycosaminoglycans (GAG) in confluent cultures of bovine aortic endothelial cells. It was found that lead at 10 and 20 microM significantly decreased the accumulation of [35S]sulfate-labeled GAG ([35S]GAG) both in the cell layer and the medium after a 24-h culture. A time course study showed that 10 microM lead decreased the accumulation of [3H]glucosamine-labeled GAG both in the cell layer and the medium after 24 h and longer. The release of [35S]GAG from the cell layer during the last 3 h of a 24 h culture was not changed by lead. The detachment of [3H]thymidine-labeled cells from the monolayer was unaffected by lead. It was shown that lead at 10 microM decreased both heparan sulfate and the other GAG in the cell layer; the former was more sensitive to lead treatment. Lead at 20 microM and below failed to increase the release of lactate dehydrogenase, suggesting that non-specific cell damage was not caused by lead. From these results, it was suggested that lead decreases endothelial cell heparan sulfate content through a decrease in the GAG production without a non-specific cell damage. Lead may be a risk factor of vascular disorders.  相似文献   

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