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991.
Santander SP Aoki M Hernandez JF Pombo M Moins-Teisserenc H Mooney N Fiorentino S 《International immunopharmacology》2011,11(6):652-660
Plant polysaccharides present an interesting potential as immunomodulators, particularly in the induction of antitumoral responses, principally because of their molecular complexity and low in vivo toxicity. Activation of dendritic cells (DCs) could improve antitumoral responses usually diminished in cancer patients, and natural adjuvants provide a possibility of inducing this activation. Herein, we investigated the immunomodulatory activity of a neutral plant polysaccharide Galactomannan on human monocyte-derived DCs (MDDC). MDDCs were stimulated with Galactomannan (GLM) from Caesalpinia spinosa and both phenotypic and functional activities were assessed by flow cytometry and real-time PCR. The phagocytic ability of MDDCs was determined by using E-coli pHrodo particles and induction of T-lymphocyte allostimulation was determined after T-cell staining with carboxyfluorescein succinimidyl ester (CFSE). In MDDCs, purified Galactomannan induced phenotypic maturation revealed by increased expression of CD83, CD86, CD206, and HLA-DR. Functional experiments showed the loss of particulate antigen uptake in Galactomannan-stimulated DCs and increased alloantigen presentation capacity. Finally, Galactomannan increased protein and mRNA levels of pro-inflammatory cytokines including IL-1β, IL-6, IL-8, IL-12p70, and TNF-α. These data reveal that Galactomannan obtained from Caesalpinia spinosa promotes effective activation of MDDCs. This adjuvant-like activity may have therapeutic applications in clinical settings where immune responses need boosting. 相似文献
992.
A water-soluble polysaccharide, named as SNP, was extracted and fractioned from the body wall of Sipunculus nudus L. by DEAE-Sepharose anion exchange and Sepharose CL-6B column chromatography. The structural characteristics of SNP investigated by high performance size exclusion chromatography (HP-SEC), Fourier transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS) indicated that SNP was a homogeneous polysaccharide with a molecular mass of 350 kD and the monosaccharide composition was determined to be rhamnose (28%), fucose (16%) and galactose (56%). SNP was able to upregulate the expression of cytokines (IL-6 and TNF-α), but did not affect IL-10 secretion by murine macrophages and human peripheral blood mononuclear cells. RT-PCR analysis demonstrated that the SNP also induced the expression of iNOS and COX-2, responsible for the induction of NO and PGE2 respectively, and SNP suppressed the arginase activity. These results suggest that the polysaccharide isolated from S. nudus activates macrophages and has potent immunostimulating activity. 相似文献
993.
目的:优选铁皮石斛类原球茎多糖提取纯化工艺。方法:采用正交试验,以多糖含量为评价指标,以液固比、浸提时间、提取次数为考察因素优选提取工艺;以样品溶液与Sevage试剂体积比、氯仿与正丁醇的体积比、反应时间为考察因素优选纯化工艺。结果:多糖最佳提取纯化工艺为80℃热水浸提多糖,液固比为20倍,提取时间2h,提取次数3次,80%乙醇沉淀,样品溶液与Sevage试剂体积比为4∶1,氯仿与正丁醇的体积比为5∶2,反应时间为5min。结论:所建方法简便、可靠、重现性好,可供本品质量控制。 相似文献
994.
红景天中红景天苷和多糖制备工艺研究 总被引:1,自引:0,他引:1
目的:优选红景天中红景天苷和多糖的制备工艺。方法:通过水提醇沉法,采用L9(34)正交试验法,以浸膏得率、红景天苷含量、多糖含量为评价指标,考察加水量、煎煮时间、煎煮次数对水提取工艺的影响;以红景天苷含量、多糖含量为评价指标,考察药液浓度、药液含醇量对醇沉工艺的影响。结果:以煎煮3次,每次加8倍量水,煎煮2 h为最佳提取工艺,以药液浓缩至每1 mL相当于原生药0.4 g,加95%乙醇醇沉,使药液含醇量70%为最佳醇沉工艺。结论:优选工艺可为新药研究和综合利用红景天资源提供参考。 相似文献
995.
目的:研究盐附子去盐方法和工艺。方法:以附子总生物碱、多糖及析盐量为指标,并与原去盐工艺相比较,优化盐附子去盐工艺。结果:新方法去盐后附片总生物碱、多糖的含量与原工艺无明显差异,且去盐时间由原来的7天(168 h)缩短至1.5 h。结论:新的去盐方法显著缩短去盐时间,节省用水量,并保证去盐产品的质量;本实验研究对盐附子去盐方法及其工艺进行了填补,另外,本实验采用总生物碱含量、多糖含量及析盐量多指标优选附子去盐方法,为附子其他炮制研究提供思路和方法,为附子炮制品质量评价提供依据。 相似文献
996.
Ethnopharmacological relevance
1-Deoxynojirimycin (DNJ) discovered from mulberry trees has been reported to be a potent inhibitor of intestinal α-glycosidases (sucrase, maltase, glucoamylase), and many polysaccharides were useful in protecting against alloxan-induced pancreatic islets damage through their scavenging ability. This study was aimed to evaluate the therapeutic effect and potential mechanism(s) of the hybrid of DNJ and polysaccharide (HDP) from mulberry leaves on alloxan-induced diabetic mice.Materials and methods
Daily oral treatment with HDP (150 mg/kg body weight) to diabetic mice for 12 weeks, body weight and blood glucose were determined every week, oral glucose tolerance test was performed after 4 and 8 weeks, biochemical values were measured using assay kits and gene expressions were investigated by RT-PCR.Results
A significant decline in blood glucose, glycosylated hemoglobin, triglyceride, aspartate transaminase and alanine transaminase levels and an evident increase in body weight, plasma insulin level and high density lipoprotein were observed in HDP treated diabetic mice. The polysaccharide (P1) showed a significant scavenging hydroxyl radicals and superoxide anion radical effects in vitro, which indicated that P1 could protect alloxan-induced pancreatic islets from damage by scavenging the free radicals and repaired the destroyed pancreatic β-cells. Pharmacokinetics assay showed that DNJ could be absorbed from the gastrointestinal mucosa and diffused rapidly into the liver, resulted in postprandial blood glucose decrease and alleviated the toxicity caused by sustained supra-physiological glucose to pancreatic β-cells. RT-PCR results indicated that HDP could modulate the hepatic glucose metabolism and gluconeogenesis by up/down-regulating the expression of rate-limiting enzymes (glucokinase, phosphoenolpyruvate carboxykinase and glucose-6-phosphatase) in liver and up-regulating the pancreatic and duodenal homeobox factor-1 (PDX-1), insulin-1 and insulin-2 expressions in pancreas.Conclusion
These findings suggested that HDP has complimentary potency to develop an antihyperglycemic agent for treatment of diabetes mellitus. 相似文献997.
苯酚-硫酸法测定麻黄多糖含量研究 总被引:5,自引:0,他引:5
目的:建立麻黄总多糖中多糖的含量测定方法。方法:采用苯酚-硫酸比色法。6%苯酚试剂1.0mL摇匀,迅速滴加浓硫酸5.0mL,即刻摇匀,放置5min后,置沸水浴加热15rain,取出冷却至室温(25℃),在490nrn波长处测定吸收度。结果:麻黄总多糖中多糖含量为66.43%,精密度及重复性良好,回收率为100.99%,RSD为1.91%。结论:此方法操作简便,准确性好,为麻黄总多糖中多糖含量测定提供了一个定量方法的同时为麻黄药材的质量控制提供了参考依据。 相似文献
998.
麻黄多糖中糖醛酸含量的测定 总被引:3,自引:1,他引:2
目的:建立麻黄多糖中糖醛酸的含量测定方法。方法:采用咔唑-硫酸比色法,具体为硫酸-硼砂溶液6mL,振摇混合,在沸水浴中煮沸5m in,以冰水浴冷却至室温,分别加入0.1g.mL-1咔唑无水乙醇溶液0.2mL,摇匀后,在沸水与中煮沸10m in,冷却后,以同样处理的重蒸馏水为空白,进行比色,于分光光度计所测得的最大吸收波长530nm处测定吸光度值(OD)。结果:麻黄多糖中糖醛酸含量为45.89%,精密度及重复性良好,回收率为101.10%,RSD为1.42%。结论:此方法操作简便,准确性好,为麻黄的质量控制提供了一个定量方法和参考依据。 相似文献
999.
黄芪多糖的胰岛素增敏作用及其对蛋白酪氨酸磷酸酯酶1B的影响 总被引:5,自引:0,他引:5
目的:探讨黄芪多糖(APS)对遗传性胰岛素抵抗小鼠的胰岛素增敏作用及其机制。方法:8周龄C57BL/6J小鼠分别饲以高脂饮食或正常饮食4周,高脂饮食小鼠以胰岛素耐量实验(ITT)证实成功复制胰岛素抵抗模型后,将动物随机分为2组:胰岛素抵抗+APS组[APS 700 mg/(kg.d),灌胃],胰岛素抵抗组(等体积生理盐水灌胃)继续饲以高脂饮食;正常饮食小鼠随机分为对照组和APS组,APS剂量和方法同前。每组动物8只,继续喂养8周后取血检测血糖及胰岛素耐量,免疫印迹法检测骨骼肌胰岛素受体β亚单位(IR-β)和胰岛素受体底物1(IRS-1)的表达,以及蛋白酪氨酸磷酸酯酶1B(PTP1B)的活性。结果:胰岛素抵抗组小鼠体重增加,血糖、血胰岛素水平显著高于对照组,胰岛素敏感性明显低于对照组。经APS治疗8周后,胰岛素抵抗小鼠的体重、餐后血糖和血胰岛素水平显著降低;骨骼肌IR-β和IRS-1酪氨酸磷酸化水平显著增强,PTP1B活性显著降低。APS治疗对对照组小鼠无明显影响。结论:APS对胰岛素抵抗小鼠具有胰岛素增敏作用;其机制与增加骨骼肌IR-β和IRS-1酪氨酸磷酸化水平,抑制PTP1B活性,增强胰岛素信号转导有关。 相似文献
1000.
目的观察仙人掌多糖对人胃腺癌SGC-7901细胞、大肠癌Lovo细胞生长的抑制作用。方法20μg/ml浓度的仙人掌多糖处理体外培养的胃腺癌SGC-7901细胞、大肠癌Lovo细胞48h后,采用MTT法检测仙人掌多糖对胃腺癌SGC-7901细胞、大肠癌Lovo细胞生长的影响,计算细胞生长抑制率。结果仙人掌多糖对胃腺癌SGC-7901细胞、大肠癌Lovo细胞的生长抑制率分别为75%及68%。结论仙人掌多糖在体外可有效抑制胃腺癌SGC-7901细胞、肠癌Lovo细胞的生长。 相似文献