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1.
The sulphation pattern of glycosaminoglycan (GAG) plays a critical role in biological functions of proteoglycans. In this study, we showed that decorins from different bovine tissues present specific sulphation pattern coupled with peculiar biological activity. In order to elucidate chemical structure of decorin glycosaminoglycan chains, we improved an electrophoretic method to analyse fluorescent disaccharides from dermatan/chondroitin sulphate GAG chains. The disaccharide separation is based on minigels, and this technique was able to define the polysaccharide chain composition in terms of sulphated and not sulphated disaccharides. This approach allowed not only the measurement of few picomoles of material, but it also permits a rapid qualitative analysis of the GAG chains. Data obtained by PAGEFS indicate that the sulphation pattern of GAG is tissue specific and this finding may explain the different binding properties to von Willebrand factor of decorins.  相似文献   

2.
Heparins and heparan sulphates from different organs, of high purity by accepted criteria, were characterized by chemical and physical (including electrophoretic and 13C-NMR spectroscopic) methods. The fat-clearing activity of these preparations was shown to be correlated with their content of the trisulphated disaccharide units I2S-ANS,6S (L-iduronic acid 2-O-sulphate-N-sulphated D-glucosamino 6-O sulphate). Species with low anti-lipemic activity contained significant proportions (greater than or equal to 30%) of nonsulphated uronic acids (especially D-glucuronic acid), and of D-glucosamino residues undersulphated at C-6, these latter residues being partially N-acetylated. Heparins from beef lung and sheep mucosa, predominantly consisting of trisulphated disaccharide units, displayed consistently higher antilipemic activity than the more heterogeneous pig mucosal heparins. The anticoagulant activity (as determined by the U.S.P., APTT and anti-Xa tests) was not a simple function of the measured physicochemical parameters. Trends were confirmed for pig mucosal heparins being more anticoagulant than beef lung preparations, and low molecular weight (usually undersulphated) species being more active in the anti-Xa test than in the U.S.P. and APTT tests.  相似文献   

3.
The tissues of rats chronically treated with tilorone exhibited a significant accumulation of acid glycosaminoglycans (GAGs): In the liver, the GAG concentration was found to be elevated by a factor of 38, in the spleen by a factor 15 and in the kidneys by a factor of 5. Furthermore, the renal excretion of GAGs was increased 32-fold as compared to control animals. Dermatan sulphate was predominant among the GAGs stored in the three organs; chondroitin sulphate and heparan sulphate were found in smaller amounts. GAG storage was accompanied by accumulation of the drug within the tissues: the molar ratio of tilorone per disaccharide unit of GAG was calculated to be one to two in each tissue. According to previous reports, tilorone-induced mucopolysacchariodosis is due to impaired lysosomal degradation of GAGs. The present results give support to the hypothesis that an interaction between the polyanionic GAGs and the dicationic drug may lead to GAG-drug complexes which cannot be digested by lysosomal enzymes.  相似文献   

4.
The effects of zinc sulphate on cholesterol-choleate-induced hypercholesterolaemia were studied in rats. Zinc sulphate (20 or 40 mg/kg, p.o. once daily for 5 days) administration, which raised serum zinc levels, significantly increased bile acid secretion and lowered high-density lipoprotein-cholesterol (HDL-C) levels in the serum. Cholesterol-choleate, given by the same route and schedule, markedly elevated serum total cholesterol level, but decreased serum HDL-C concentration. Bile acid in serum and in bile was also increased, but these changes were inhibited by zinc sulphate pretreatment. Zinc sulphate also worsened the decrease in HDL-C and slightly prolonged the elevation in total cholesterol produced by cholesterol-choleate administration. It is concluded that the moderate increase in serum total cholesterol level by zinc sulphate could be due to inhibition of hepatic metabolism of cholesterol to bile acid. The specific action of zinc ions on HDL-C metabolism is discussed.  相似文献   

5.
Effectiveness, safety, and tolerability of instillation therapy with chondroitin sulphate (CAS 9082-07-9, Gepan instill) was investigated in a non-interventional study. 286 patients with clinically diagnosed chronic forms of cystitis, such as bladder pain syndromelinterstitial cystitis, radiation cystitis, overactive bladder syndrome and chronically-recurring cystitis were included. The course of symptoms was documented over 8 instillations at maximum, covering a period of approximately three months. All main symptoms of chronic cystitis declined consistently and statistically significantly (p < 0.0001). Both daytime and nighttime micturition frequencies as well as the score levels of urgency and pain declined significantly during the course of treatment. The functional bladder capacity as indicated by the volume of first morning voiding increased from 157.9 ml +/- 7.5 to 186.7 ml +/- 6.9 (mean +/- SE; p < 0.0001). The level of urgency decreased from 6.8 +/- 0.1 to 3.4 +/- 0.2 (mean +/- SE; numerical rating scale (11-point box scale); p < 0.0001) and nocturia decreased from 4.0 +/- 0.2 to 2.1 +/- 0.1 times (mean +/- SE; p < 0.0001). Chondroitin sulphate instillation was effective and well tolerated in the therapy of chronic forms of cystitis associated with a possible GAG layer deficit (GAG layer: mainly composed of the glycosaminoglycans chondroitin sulphate, dermatan sulphate and heparan sulphate), but the results need to be confirmed in a controlled study.  相似文献   

6.
Leukocyte arylsulphatase A (AS-A) was shown to be significantly high in newly-diagnosed breast cancer patients. Previous reports imply a connection between serum interleukin-6 (IL-6) and breast cancer, possibly through a modulation of enzymes involved in estrogen synthesis. Abnormal distribution of heparan sulphate proteoglycans (HSPGs) in malignant breast epithelial cells suggests that they play a key role in the regulation of cell growth. Estradiol is believed to be effective in modulating glycosaminoglycans (GAGs) and their depolymerizing enzymes. Therefore, in this study, attempts were made to evaluate the activity of leukocyte arylsulphatase A, serum interleukin-6, urinary GAGs and heparan sulphate (HS) in response to tamoxifen (TAM) therapy in mastectomised breast cancer patients. Thirty-four patients (aged 30-82 years) were administered TAM (20 mg twice daily). Blood and urine samples of each patient were collected three times (at the beginning, and in third and sixth month of TAM therapy), and biochemical parameters were measured. There was no difference between baseline leukocyte AS-A activity and that measured after three months. At the end of six months, enzyme activity was significantly higher than the former values (p=0.022), but within the reference intervals reported in the literature. Although this increase might imply a normalization, the duration of TAM therapy is not long enough to make a decision about either regression or aggravation of the disease. TAM did not have any effect on serum IL-6, urinary HS and GAG levels which may be due to insensitivity of these variables to TAM during the short period of therapy. Both urinary GAG and HS levels measured at sixth month exhibited a positive correlation with the baseline level of leukocyte AS-A (p=0.005 and 0.009, respectively), suggesting that positive responses to the drug might be seen in patients with low AS-A activity.  相似文献   

7.
The effect of high doses of histamine (Hi) on collagen and glycosoaminoglycan (GAG) content in skin wounds of rats was studied on days 1, 3, 5, 10 and 14 after wounding. Injection of high doses of Hi into the wounded area inhibited colagen production, collagen polymerization and GAG synthesis; levels of chondroitin sulphates (chondroitin-4,6-sulphate and dermatan sulphate) and hyaluronic acid were decreased.  相似文献   

8.
Exposure to diesel exhaust (DE) induces lesions in lung epithelium by generation of reactive oxygen species. Glycosaminoglycans (GAG), components of extracellar matrix, are thought to play important roles in cell proliferation and differentiation in the repair process of injured tissue. We investigated how GAG are related to the recovery of lung tissue from injury. Using high-performance liquid chromatography analysis, we determined the amounts of GAG, such as chondroitin sulfate (CS), dermatan sulfate (DS), and hyaluronan (HA) in the lungs of rats exposed to DE for 4 weeks at concentrations of 0.3 or 3 mg/m(3) as suspended particulate matter, or to filtered air. The contents of CS and HA in the surroundings of the bronchi were significantly increased after exposure to DE. In addition, immunohistochemical staining showed that the number of 8-hydroxydeoxyguanosine-positive cells as a marker of cell damage, and proliferating cell nuclear antigen-positive cells also increased in the same areas in which the levels of GAG were elevated in the lungs of rats exposed to 3 mg/m(3) DE. These results suggest that CS and HA in the lung contribute to cell proliferation and remodeling in the process of recovery from injury caused by exposure to DE.  相似文献   

9.
虫草菌丝对酒精性脂肪肝大鼠治疗效果的研究   总被引:2,自引:0,他引:2  
目的探讨虫草菌丝对酒精性脂肪肝大鼠模型的治疗效果。方法将40只SD大鼠随机分成4组:正常对照组、模型组、饮食治疗组和虫草菌丝治疗组。实验末处死所有大鼠,检测血清天门冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT)、总胆固醇(TC)、三酰甘油(TG)。同时行肝脏病理组织学检查。结果虫草菌丝治疗组大鼠血清AST、ALT、TC、TG明显低于模型组。虫草菌丝组大鼠肝细胞脂肪变及炎症明显改善。结论虫草菌丝对酒精性脂肪肝有治疗作用。  相似文献   

10.
Heparin and other iduronic acid-containing glycosaminoglycans (GAG) such as dermatan sulfate exert their anticoagulant properties primarily by accelerating the rate of inhibition of the natural protease inhibitors antithrombin III (AT, which inhibits both factor Xa and thrombin) and heparin cofactor II (HCII, which selectively inhibits thrombin). Although AT and HCII are structural homologs, only heparin binds to AT, and HCII has different binding sites for heparin and dermatan sulfate. Whereas the binding site of heparin for AT is a unique pentasaccharide sequence contained in only about one third of the chains of this GAG, HCII-binding sequences of heparin and dermatan sulfate are less specific and contained in practically all the GAG chains. Protein binding and associated biological activities of heparin and dermatan sulfate are modulated by the "plasticity" of their iduronic acid residues due to the availability of up to three equienergetic conformation among which the protein selects the one favouring the most stable complex. Glycol-splitting of nonsulfated uronic acid residues, a device for generating flexible joints along the GAG chains, has different effects on different binding domains. Whereas it inactivates the binding site for AT causing a drop of the anticoagulant activity, it enhances the HCII-associated activity of both heparin and dermatan sulfate.  相似文献   

11.
A simple and highly sensitive high-performance liquid chromatographic method is described for the determination of valproic acid in human serum. The method is based on the direct derivatization of serum sample with 6,7-methylenedioxy-1-methyl-2-oxo-1,2-dihydroquinoxaline-3-ylpr opionohydrazide. The derivatization reaction proceeds in aqueous solution in the presence of pyridine and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide at 37 degrees C. The resulting derivatives were separated on a reversed-phase column (YMC Pack ODS-A) with isocratic elution and were fluorimetrically detected at 440 nm with excitation at 365 nm. The detection limit (signal-to-noise ratio=3) for valproic acid added to serum sample was 0.1 microg (700 fmol)/ml serum sample (2.3 fmol on column). The method was applied to determine the unbound- and total-valproic acid levels in the serum obtained from three healthy volunteers after oral administration of the drug (600 mg).  相似文献   

12.
The effects of indomethacin on glycosaminoglycan (GAG) metabolism during the development of experimental osteoarthritis produced by the immobilization of the knee in extension were studied in adult rabbits. The rabbits received intraperitoneal injections of indomethacin (10 mg/kg) daily for 17 days. The GAG content of the samples taken from the articular and periarticular connective tissues of the knee was assayed from determinations of hexosamine and uronic acid concentrations following papain proteolysis and subsequent purification. The uptake of 35S-sulphate (calculated as DPM/μg galactosamine) was used as an indicator of the synthesis rate of sulphated GAGs. The controls comprised normal rabbits, rabbits treated with indomethacin, rabbits immobilized for 17 days, and the non-immobilized contralateral leg of the immobilized rabbits receiving indomethacin.Indomethacin treatment failed to inhibit the uptake of 35S-sulphate in rabbits. The concentration of chondroitin sulphates was normal or elevated in animals receiving indomethacin. The drug did not prevent the loss of GAGs from the weight-bearing cartilage of the immobilized knees, but in tibial marginal tissues it prevented the accumulation of GAGs to some extent.  相似文献   

13.
A simple and rapid sweeping method for the online improvement of detection sensitivity of the main alkaloids of Coptidis Rhizoma has been developed in this work. Optimum separation conditions were found as follows: electrophoretic running solution comprising 100 mM phosphoric acid, 15 mM sodium dodecyl sulfate (SDS) and 10% (v/v) tetrahydrofurane with pH 1.82; running voltage of -25 kV; sample matrix composed of 50 mM phosphoric acid and sample injection at 1000 mbar for 60 s (sample injection volume ca. 2.75 microl). With this sweeping method, the concentration limits of detection of berberine, coptisine and palmatine were found to be 2.5 ppb (ng/ml), which was about 500 times lower than those from conventional sample injections. Baseline separation was achieved for the main alkaloids within 15 min. After validation, the developed method was applied to determine the quantity of berberine, coptisine and palmatine in a Coptidis Rhizoma sample. The method should be able to be used in identification and quantitative evaluation of the crude drugs requiring only a minor amount of sample.  相似文献   

14.
虫草菌丝对实验性肝硬化大鼠肝组织胰岛素酶活性的影响   总被引:1,自引:0,他引:1  
目的 :探讨虫草菌丝对实验性肝硬化大鼠肝组织匀浆上清液胰岛素酶活性的动态影响及其可能机制。方法 :以CCl4诱导大鼠肝硬化模型 ,设立正常组、模型组和虫草组。正常组于实验开始时便处死大鼠 ,而后 2组则于造模 3 ,6,9wk分批处死 ,取血及肝组织标本。生化法测定血清丙氨酸转氨酶(ALT)、清蛋白 (ALB)含量 ,放射免疫法测定血清透明质酸 (HA)、血清胰岛素 (INS)含量及肝组织匀浆上清液的胰岛素酶活性。结果 :(1 ) 3 ,6wk虫草组大鼠血清ALT ,ALB及HA含量与对应模型组差异无显著意义 (P >0 .0 5 ) ,9wk虫草组大鼠血清ALT ,HA含量显著低于对应模型组 (P <0 .0 5 ) ,而其血清ALB含量则显著高于对应模型组 (P<0 .0 5 ) ;(2 ) 3wk虫草组及模型组大鼠血清INS水平及肝组织胰岛素酶活性与正常组大鼠差异无显著意义 (P >0 .0 5 ) ,6,9wk虫草组及模型组大鼠血清INS水平显著高于正常组 (P <0 .0 5 ) ,而对应的肝组织胰岛素酶活性则显著低于正常组 (P <0 .0 5 ,或P <0 .0 1 ) ;(3 ) 3 ,6,9wk虫草组大鼠血清INS水平及肝组织胰岛素酶活性与对应模型组差异无显著意义(P >0 .0 5 )。结论 :虫草菌丝可减轻CCl4对肝细胞的损伤 ,并可抑制肝纤维化 ;造模 6wk后实验性肝硬化大鼠肝组织胰岛素酶活性开始降低 ,血清INS含量开始升高  相似文献   

15.
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   

16.
A randomized blinded clinical trial was performed in 53 patients bitten by Bothrops sp. and Porthidium sp. in Antioquia and Chocó, Colombia, in order to compare the efficacy and safety of two antivenoms made of whole IgG obtained by either ammonium sulphate (monovalent anti-B. atrox) or caprylic acid (polyvalent) fractionation. Additionally, antivenoms were compared by electrophoretic and chromatographic analyses and anticomplementary activity in vitro. With a protocol of 2, 4 and 6 antivenom vials for the treatment of mild, moderate and severe envenomings, respectively, both antivenoms were equally efficient to neutralize the most relevant signs of envenoming and to clear serum venom levels in patients from the first hour and later on. Three patients with severe envenoming and initially treated with less than six vials on admission had persistent or recurrent venom antigenemia within 12-48 h. Monovalent antivenom fractionated by ammonium sulphate precipitation had higher amounts of protein aggregates and nonimmunoglobulin proteins than polyvalent antivenom fractionated by caprylic acid precipitation. Both antivenoms presented anticomplementary activity in vitro, being higher in the monovalent product. In agreement, monovalent antivenom induced a significantly higher incidence of early antivenom reactions (52%) than polyvalent antivenom (25%).  相似文献   

17.
The concentration of inorganic sulphate in serum of the rat (about 0.9 mM) could be lowered in the following three different ways. (1) Oral administration of sodium chloride (8 mmol/kg) decreased serum sulphate within 2 hr to 0.5 mM. Eight hours after administration serum sulphate had returned to the control level. (2) Feeding of a low-protein diet (8 per cent casein, without supplements of sulphur-containing amino acids or inorganic sulphate salts) reduced urinary sulphate excretion in 2 days to 10 per cent of control. Concomitantly, serum sulphate was decreased to half the control level. (3) Paracetamol (1.0 or 1.5 mmol/kg, orally), a substrate of sulphation, reduced serum sulphate within 3 hr to 30 per cent of control. Eight hours after administration the sulphate concentration tended to rise again. Fasting initially increased serum sulphate; after 3 days of fasting still considerable amounts of inorganic sulphate were excreted in urine (50–70 per cent of control). Even after 3 days serum sulphate was not yet significantly decreased below control. Lowering of the serum sulphate concentration results in a decreased availability of inorganic sulphate.Sulphation of a high dose of phenol (266 μmol/kg) was decreased at a serum concentration of sulphate of 0.3 mM, presumably because sulphate was depleted by the high dose of phenol. Feeding the low-protein diet, however, caused no decrease in sulphation at a tracer dose of [14C]-phenol (1.25 μmol/kg), while paracetamol pretreatment did cause a decrease in the fraction of the dose that became sulphated, probably because remaining unconjugated paracetamol competed with phenol for sulphation; the tracer dose of [14C]-phenol did not further deplete sulphate. The findings are discussed in relation to implications for the toxicity of many xenobiotics that are eliminated as sulphate conjugates.  相似文献   

18.
The absorption of ciprofloxacin has been reported to be impaired by concomitant administration of ferrous sulphate. The effects of sodium ferrous citrate and ferric pyrophosphate, which have been used as extensively as ferrous sulphate, on the absorption of ciprofloxacin were compared with that of ferrous sulphate. The effects of ascorbic acid on the interactions between ciprofloxacin and each iron compound were studied in mice. Mice were treated orally with ciprofloxacin (50 mg kg(-1)) alone, the iron compound (ferrous sulphate, sodium ferrous citrate or ferric pyrophosphate; 50 mg elemental iron kg(-1)) alone, ciprofloxacin with each iron compound or ciprofloxacin in combination with each iron compound and ascorbic acid (250 mg kg(-1)). The maximum serum concentration of ciprofloxacin was significantly (P < 0.01) reduced from 1.15+/-0.11 microg mL(-1) (ciprofloxacin alone) to 0.17+/-0.01, 0.27+/-0.01 or 0.28+/-0.02 microg mL(-1), respectively, when ferrous sulphate, sodium ferrous citrate or ferric pyrophosphate was administered along with ciprofloxacin. The addition of ascorbic acid did not affect the inhibitory effects of each iron compound on the absorption of ciprofloxacin. Ciprofloxacin did not affect the variation of serum iron levels after administration of each iron compound. The addition of ascorbic acid significantly (P < 0.01) enhanced the increase in serum iron concentration after administration of sodium ferrous citrate, showing an increase from 270+/-6 microg dL(-1) to 463+/-11 microg dL(-1) compared with an increase from 248+/-8 microg dL(-1) to 394+/-18 microg dL(-1) after administration of sodium ferrous citrate alone. Ascorbic acid also caused a significant (P < 0.01) increase in serum iron concentration from 261+/-16 microg dL(-1) to 360+/-12 microg dL(-1) after administration of ferric pyrophosphate, although it did not affect the levels after ferrous sulphate administration. The results suggest that sodium ferrous citrate and ferric pyrophosphate should not be administered with ciprofloxacin (as for ferrous sulphate) and that sodium ferrous citrate is converted to the ferric form more easily than ferrous sulphate. This difference in convertibility might contribute to a clinical difference between sodium ferrous citrate and ferrous sulphate.  相似文献   

19.
酸性多糖中糖醛酸还原方法的改良   总被引:1,自引:0,他引:1  
目的 对酸性多糖中糖醛酸羧基还原条件进行改良并确定最佳还原条件。方法 将钠型和氢型酸性多糖样品分别用不同缓冲液体系溶解,采用碳二亚胺-硼氢化钠(EDC - NaBH4)法还原,用高效液相色谱(HPLC)法测定糖醛酸还原率。结果 氢型多糖中的糖醛酸比钠型多糖更容易还原;在改良的75%四氢呋喃 - 0.1 mol.L-1 2-吗啉乙磺酸(THF - MES)缓冲体系中,氢型多糖中糖醛酸一次还原率达98.1%。结论 该改良方法明显提高酸性多糖中糖醛酸还原率,且适用于甘露糖醛酸、透明质酸、低分子肝素及岩藻糖硫酸酯中糖醛酸的还原。  相似文献   

20.
Rabbits were fed with normal (group 1 and 2) and cholesterol rich diets (group 3 and 4) concomitantly to a daily peroral administration of 50 mg/kg procyanidolic oligomers (PCO) to groups 2 and 4. After 10 weeks, the cholesterol content of the blood serum and the excised aortic intima-media were significantly higher in groups 3 and 4 than in groups 1 and 2.The DNA, hydroxyproline, uronic acid contents were similar in aortic dry weight basis in all four groups.The intima-media samples were extracted successively with 0.15 M NaCl, 0.02 M sodium phosphate pH 7.4 (NaCl extract) and with 4M guanidinium chloride, 0.05 M sodium acetate pH 5.8 prior (G1 extract) and following (G2 extract) hydrolysis of the collagen with collagenase.The cholesterol contents of G1 extracts were higher in groups 2 and 4 than in groups 1 and 3.The cholesterol content of aortic elastin increased with cholesterol feeding (group 3). With simultaneous administration of cholesterol and PCO the cholesterol content of aortic elastin in group 4 was significantly lower than in group 3.The uronic acid contents increased in G1 extracts and in the collagenase digest with PCO treatment of both normal and hypercholesterolemic rabbits. The ratio of dermatan-sulphate to chondroitinsulphate decreased with hypercholesterolemia (group 3) and with PCO (group 2 and 4). The parallelism between increased cholesterol and uronic acid contents and modified glycosaminoglycan composition in Gl extract, indicate that the interaction of cholesterol with macromolecules of the aorta can be modulated by PCO. This drug modifies the extractibility of aortic cholesterol and glycosaminoglycans and reduces the association of cholesterol to elastin.  相似文献   

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