岩藻聚糖硫酸酯对血小板黏附和聚集的影响

目的研究褐藻中岩藻聚糖硫酸酯对血小板黏附和聚集的影响。方法将20只新西兰白兔随机分为2组：岩藻聚糖硫酸酯组和空白对照组,分别进行血小板黏附试验（PAdT）、血小板聚集试验（PAgT）和血栓素B2（TXB2）测定。结果岩藻聚糖硫酸酯组和空白对照组血小板黏附试验的黏附率测定分别为16.7±6.3%、32.6±9.5%,P〈0.05,差别有显著意义;血小板聚集试验的最大聚集率测定分别为56.2±7.8（S）、78.4±10.7（S）,P〈0.05,差别有显著意义;血栓素B2测定分别为16.2±3.8ng/L、123.6±41.3ng/L,P〈0.05,差别有显著意义。结论岩藻聚糖硫酸酯抑制血小板的黏附与聚集。     

岩藻聚糖硫酸酯抗肿瘤作用机制

岩藻聚糖硫酸酯是一种具有多种生物活性的硫酸多糖,如抗凝血、降血脂、抗肿瘤等,抗肿瘤作用机制包括免疫调节、诱导肿瘤细胞凋亡和抑制新血管生成等.     

Anticancer Activity of Fucoidan via Apoptosis and Cell Cycle Arrest on Cholangiocarcinoma Cell

Objective: Many previous studies reported that fucoidan has antitumor activities. The objective of the present study was to determine the cytotoxic effects and related mechanisms of cell death induced by fucoidan extracted from Fucus vesiculosus on CL-6 cholangiocarcinoma cell. Methods: CL-6 and OUMS cells were treated with 0, 100, 200, and 300 μg/mL of fucoidan. MTT assay was used to determine cytotoxicity. Flow cytometry-based assay was used to examine the distribution of apoptosis and cell cycle. The changes in nuclear morphology were determined using Hoechst 33,342 staining. Mitochondrial membrane potential (ΔΨm) was evaluated using the JC-1 kit. The apoptotic, anti-apoptotic, and cell cycle-related proteins study were examined by Western blot analysis. Results: The relative viable cell number of treated CL-6 cells was decreased but no effect was observed in OUMS normal cells. Furthermore, treated cells were arrested in the G0/G1 phase with down-regulation of cyclin D1 and CDK4. Annexin V/PI staining with flow cytometry analysis suggested that fucoidan could induce apoptosis in CL-6 cells. Western blot study revealed the up-regulation of apoptotic markers including Bax, cleaved PARP, cleaved caspase-3, but down-regulation of anti-apoptotic markers,  cl-2. Moreover, fucoidan could induce nuclear fragmentation and chromatin condensation with alteration of ΔΨm.  Conclusion: Fucoidan exerts antitumor properties against CL-6 cholangiocarcinoma cells illustrated by the induction of apoptosis and cell cycle arrest.     

褐藻多糖硫酸酯对阿霉素肾硬化大鼠肾组织FN、TGF-β、MMP-9的影响

目的 观察褐藻多糖硫酸酯(FPS)对阿霉素肾硬化大鼠肾脏的保护作用.方法 将40其SD大鼠分成正常组、模型组、海昆肾喜组(褐藻多糖硫酸酯组)、盐酸贝那普利组.建立阿霉素肾硬化大鼠模型,分别采用相应药物干预;8周后观察各组大鼠肾脏病理改变,PAS观察肾小球系膜基质,免疫组化观察肾脏组织纤连蛋白(FN),Western blot观察转化生长因子β(TGF-β)和金属蛋白酶-9(MMP-9)的表达.结果 FPS能减轻肾小球系膜基质增生,且能减少TGF-β、FN表达,上调肾皮质MMP-9的表达.相关性分析研究显示,TGF-β值与FN、系膜基质指数呈正相关;MMP-9值与FN、系膜基质指数呈负相关.结论 FPS可能通过调控TGF-β及MMP-9表达,减轻FN沉积,从而抑制肾小球硬化.     

Inhibitory Effect of Oversulfated Fucoidan on Invasion through Reconstituted Basement Membrane by Murine Lewis Lung Carcinoma

We investigated the effects of native, Oversulfated, and desulfated fucoidans and heparin on the invasion of 3LL cells through Matrigel. Of the four polysaccharides tested, Oversulfated fucoidan was the most potent inhibitor of tumor cell invasion and inhibited most potently and specifically the tumor cell adhesion to laminin. Sodium dodecyl sulfate-polyacrylamide gel electrophoretic analysis of the binding of elastase-cleaved laminin to fucoidan- and heparin-Sepharoses showed that both polysaccharides bound to the 62 and 56 kDa fragments. Pretreatment of 3LL cells with native or Oversulfated fucoidan reduced their adhesive potency to laminin. The two fucoidans inhibited further the laminin binding of 3 LL cells which had been pretreated with a laminin-based pentapeptide, YIGSR. These results suggest that fucoidan specifically binds to not only the heparin binding domain(s) of laminin but also site(s) other than the cell surface laminin receptor. 3 LL cells secreted a 50 kDa form of urokinase-type plasminogen activator (u-PA). The extracellular level of u-PA activity was increased 1.7 times by addition of laminin but not type IV collagen. Oversulfated fucoidan most potently reduced the increased u-PA levels. Therefore, the reduction in in vitro invasiveness of 3 LL cells in response to either fucoidan or its Oversulfated derivative may result from an inhibition of physical interaction between the tumor cells and the Matrigel (laminin), followed by a suppression of the laminin-induced increase in extracellular u-PA.     

褐藻多糖硫酸酯对腺嘌呤致大鼠肾间质纤维化的干预作用及其机制探讨

目的：观察褐藻多糖硫酸酯（FPS）对大鼠慢性肾衰竭模型肾间质纤维化的干预作用,并初步探讨其机制。方法：将Wistar雄性大鼠随机分为3组,即：（1）正常对照组（n=15）;（2）CRF模型组（n=24）,进食含0.75%腺嘌呤的饲料;（3）CRF＋FPS治疗组（n=24）,在进食含0.75%腺嘌呤饲料的同时每天给予FPS 200mg.kg-1.d-1灌胃。持续喂养6周。于第2、4、6周末收集大鼠血、尿标本,应用自动分析仪测定血肌酐、白蛋白和24h尿蛋白;并留取肾组织,Masson染色切片分析肾间质纤维化程度,免疫组化方法半定量分析肾组织中α平滑肌肌动蛋白（α-SMA）的表达。结果：CRF＋FPS治疗组大鼠24h尿蛋白均明显低于同期CRF模型组（P〈0.05）,白蛋白水平6周时明显高于CRF模型组（P〈0.01）,但两组间血肌酐水平无统计学差异（P〉0.05）。CRF＋FPS治疗组大鼠肾组织Masson染色间质纤维化指数评分也明显低于同期CRF模型组（P〈0.01）,该肾组织α-SMA蛋白表达2、4、6周均明显低于同期CRF模型组（P〈0.05）。结论：FPS治疗可以减少腺嘌呤致肾衰竭大鼠的尿蛋白排泄,减轻肾间质纤维化程度,其机制可能与抑制肾小管上皮细胞-间充质细胞转化有关。     

褐藻糖胶的免疫调节作用

观察了从海带中提取的褐藻糖胶对小鼠免疫功能的影响，褐藻糖胶在体外可诱导白细胞介素１（ＩＬ－１）和丙型干扰素（ＩＦＮ－γ）产生；体内给药可增强Ｔ细胞，Ｂ细胞，巨噬细胞（Ｍ）和自然杀伤细胞（ＮＫ细胞）功能，促进对绵羊红细胞（ＳＲＢＣ）的初次抗体应答。