鼠尾藻的化学成分研究

 目的 研究鼠尾藻的化学成分。方法 采用正相及反相硅胶柱色谱、Sephadex LH-20凝胶柱色谱、半制备高效液相色谱等方法进行分离纯化,根据理化性质及波谱学数据鉴定化合物的结构。结果 从鼠尾藻乙醇提取物中,分离鉴定了15个化合物,其中9个异戊二烯类化合物,分别为黑麦草内酯（1）,异黑麦草内酯（2）,loliolide acetate（3）,蚱蜢酮（4）,apo-9′-fucoxanthinone（5）,3α-hydroxy-5,6-epoxy-7-megastigmen-9-one（6）,deacetylate-apo-13′-fucoxanthinone（7）,apo-13′-fucoxanthinone（8）,(R)-(-)-3-羟基-β-紫罗兰酮（9）,6个其他类型的化合物,sargassum ketone（10）,2-heptenoic acid-4,4-dihydroxy-2,3-dimethyl-γ-lactone（11）,(R)-2-hydroxy-3-phenylpropanamide（12）,脱氧核糖胸腺嘧啶（13）,岩藻甾醇（14）,甘油脂肪酸酯（15）。结论 deacetylate-apo-13′-fucoxanthinone (7) 为新化合物,化合物3,5,6,8,9,15为首次从该属植物中分离得到。     

羊栖菜多糖对内毒素诱导的大鼠肝星状细胞增殖活化、氧化损伤及凋亡的影响

目的:观察羊栖菜多糖(sargassum fusiforme polysaccharides,SFPS)对内毒素(lipopolysccharide,LPS)诱导的肝星状细胞HSC-T6的增殖活化、氧化损伤及凋亡的影响,并探讨其抗纤维化的机制.方法:将大鼠HSC-T6细胞株置DMEM培养液中,37℃50mL/L CO2条件下培养传代后分为空白对照组、LPS模型组、LPS+不同剂量SFPS组.加药处理48h后,MTT比色法检测细胞增殖;Annexin V-FITC标记法检测细胞的凋亡;比色法检测MDA/SOD的含量;采用ELISA法检测Ⅰ型胶原蛋白的表达;Western blot法检测?-SMA的表达.结果:LPS能明显诱导HSC-T6的增殖、提高MDA的分泌及Ⅰ型胶原和?-SMA的表达、降低SOD的分泌;与模型组相比,SFPS(25、50、100mg/L)组可以不同程度抑制HSC-T6增殖并能诱导其凋亡、减少MDA分泌及Ⅰ型胶原和?-SMA的表达、增加SOD的分泌(均P<0.05).结论:SFPS可能具有一定的抗纤维化作用,其与诱导HSC-T6凋亡及保护LPS诱导的HSC-T6细胞氧化应激损伤有关.     

Defensive nature of Sargassum polycystum (Brown alga) against acetaminophen-induced toxic hepatitis in rats: Role of drug metabolizing microsomal enzyme system, tumor necrosis factor-a and fate of liver cell structural integrity

AIM: To assess the defensive nature of Sargassum polycystum (S. polycystum) (Brown alga) against acetaminophen (AAP)-induced changes in drug metabolizing mi crosomal enzyme system, tumor necrosis factor (TNF-α) and fine structural features of the liver during toxic hepatitis in rats. METHODS: Male albino Wistar strain rats used for the study were randomly categorized into 4 groups. GroupⅠconsisted of normal control rats fed with standard diet. GroupⅡrats were administered with acetaminophen (800 mg/kg body weight, intraperitoneally). GroupⅢrats were pre-treated with 5. polycystum extract alone. GroupⅣrats were orally pre-treated with S. polycystum extract (200 mg/kg body weight for 21 d) prior to acetaminophen induction (800 mg/kg body weight, intraperitoneally). Serum separated and liver was excised and microsomal fraction was isolated for assaying cytochrome P450, NADPH Cyt P450 reductase and bs. Serum TNF-αwas detected using ELISA. Fine structural features of liver were examined by transmission electron microscopy. RESULTS: Rats intoxicated with acetaminophen showed considerable impairment in the activities of drug metabolizing microsomal enzymes, such as cytochrome P450, NADPH Cyt P450 reductase and bs when compared with the control rats. The rats intoxicated with acetaminophen also significantly triggered serum TNF-αwhen compared with the control rats. These severe alterations in the drug metabolizing enzymes were appreciably prevented in the rats pretreated with 5. polycystum. The rats pretreated with S. polycystum showed considerable inhibition in the elevation of TNF-αcompared to the rats intoxicated with acetaminophen. The electron microscopic observation showed considerable loss of structural integrity of the endoplasmic reticulum, lipid infiltration and ballooning of mitochondria in the acetaminophen-intoxicated rats, whereas the rats treated with S. polycystum showed considerable protection against acetaminophen-induced alterations in structural integrity. CONCLUSION: These observations suggest that the animals treated with 5. polycystum extract may have the ability to protect the drug metabolizing enzyme system and mitochondrial functional status from free radical attack, thereby showing its defense mechanism in protecting hepatic cells from acetaminophen toxic metabolite N-acetyl-para-benzoquinone-imine (NAPQI).     

羊栖菜硫酸多糖通过PI3K/AKT通路抑制H2O2诱导的MRC-5细胞氧化损伤

目的 为阐明羊栖菜硫酸多糖(SFPS Ⅲ)对过氧化氢(H2O2)诱导的正常人胚肺细胞(MRC-5)氧化应激损伤的保护作用及潜在分子机制。方法 试验通过噻唑蓝(MTT)法检测MRC-5细胞暴露于H2O2或SFPS Ⅲ后的活力,Hoechst染色法检测细胞凋亡形态,流式细胞仪测定细胞凋亡率,酶联免疫吸附试验测定超氧化物歧化酶(SOD)和谷胱甘肽过氧化酶(GSH-Px)活性、一氧化氮(NO)和丙二醛(MDA)含量。通过免疫印迹Western blot检测相关蛋白水平。结果 H2O2处理使MRC-5细胞活力显著降低(P < 0.05),而SFPS Ⅲ(200～600 μg.mL-1)干预可明显增强MRC-5细胞活力。酶联免疫法结果表明,SFPS Ⅲ干预抑制H2O2诱导的细胞内NO和MDA的过度分泌,并增加了H2O2诱导的细胞内SOD和GSH-Px的活性。免疫印迹结果表明,120 μmol.L-1 H2O2处理的细胞中p-AKT和p-mTOR相对蛋白表达水平下调,而p-AKT和p-mTOR相对蛋白表达水平在SFPS Ⅲ处理的MRC-5细胞中被逆转。结论 SFPS Ⅲ对H2O2诱导的MRC-5细胞氧化应激损伤具有保护作用,其机制可能是激活PI3K/AKT/mTOR通路发挥其抗凋亡作用。研究结果为羊栖菜高附加值产品开发及天然、安全抗氧化功能因子的筛选提供了一定的理论依据。     

海篙子海带混合提取褐藻胶的研究

初步研究了海蒿子和海带混合提取褐藻胶的工艺条件;测定了海蒿子和海带不同组成配比制备的一系列混合胶的粘度;对混合胶进行了粘度稳定性和破坏性试验以及金属离子对粘度的影响研究。实验发现,当海带与海蒿子以1:1组成混合时提取的褐藻胶粘度稳定性最差,40℃保存10d后,剩余粘度百分率为74.1％,80℃加速降解时后,剩余粘度百分率为41.0％。金属离子都能降低混合胶的粘度,其中Fe~(3+)影响最大,Ca~(2+)、Mg~(2+)次之,Na~+影响最小。     

鼠尾藻多糖清除氧自由基作用的研究：Ⅰ.对O2与OH抑制活性的评价

采用化学发光分析法研究鼠尾藻多糖清除氧自由基活性。结果表明，鼠尾藻多糖具有较强的清除Ｏ＾－２与．ＯＨ的能力，抑制发光强度ＣＩＣ５０值分别为０．１ｍｇ／ｍＬ和１．５ｍｇ／ｍＬ，提示该多糖对Ｏ＾－２的清除作用更为有效。     

含反药配伍的海藻玉壶汤临床应用分析

目的:;分析临床研究报道的海藻玉壶汤中海藻与甘草的配伍规律与特点,以便为反药配伍的深入研究提供参考依据。方法:;甘草”反药药对的文献,针对其主治病证、证候类型、随证配伍使用的中药及成方、海藻与甘草用法用量等进行数据分析。结果:;检索得到海藻玉壶汤文献共计1137篇,其中含有“海藻甘草”反药配伍的文献共计60篇,占总数的5.28%;以海藻玉壶汤为主方,随症加减用于妇科、男科、皮肤科等多种疾病,而并非单纯局限于对瘿病的治疗;其主治病证中证候类型以气滞痰凝型为主;海藻玉壶汤应用于临床,多与化痰药、活血化瘀药、理气药、清热药、补益药等配伍使用;海藻与甘草比例以2∶1~5∶1之间的较为常见,占文献总数的74.60%,均未见不良反应报道。结论:;含有反药配伍的海藻玉壶汤在临床应用中范围较广;其主治病证中证候类型仍以气滞痰凝型为主,与原方应用相吻合;海藻与甘草配伍比例与原方有明显差异。      

马尾藻中几种金属元素含量及存在形态测定

以马尾藻为原料,采用不同的溶剂进行提取,分别得到脂溶性组分、水溶性组分、酸溶性组分、碱溶性组分和残渣组分;利用原子吸收分光光度法测定其中Ca、Zn、Mg、Pb、Cd等5种金属元素的含量。结果表明:所测定的5种元素中,Ca在马尾藻中含量最高,而Pb含量最低;上述金属元素在马尾藻中以多种形态共存。     

Effect of Sargassum thunbergii on ROS mediated oxidative damage and identification of polyunsaturated fatty acid components

In this study, we examined protective effect of Sargassum thunbergii on reactive oxygen species (ROS) mediated oxidative stress in cellular systems. In addition, polyunsaturated fatty acids from S. thunbergii were identified and quantified by gas chromatography mass spectroscopy. Intracellular ROS levels were measured using a oxidation sensitive dye, 2′,7′-dichlorofluorescein diacetate (DCFH-DA). Treatment with S. thunbergii significantly reduced intracellular ROS mediated cell damage and inhibited myeloperoxidase (MPO) activity assessed in tumor necrosis factor-α (TNF-α) stimulated human monocytic leukemia in a concentration-dependent manner. Moreover, antioxidative mechanisms by S. thunbergii were evaluated by measuring the expression levels of antioxidative enzymes such as superoxide dismutase (SOD-1), catalase, glutathione peroxidase and glutathione reductase. SOD-1 and glutathione reductase were up-regulated by S. thunbergii. Furthermore, S. thunbergii contains polyunsaturated fatty acids such as arachidonic acid, arachidic acid, palmitic acid, elaidic acid, linoleic acid, stearic acid and cis-5,8,11,14,17-eicosanoic acid. Therefore, these results suggested that S. thunbergii has nutraceutical effectiveness in prevention of ROS-induced tissue damage and potential natural antioxidant related to oxidative stress, which can be traceable to polyunsaturated fatty acids contained in S. thunbergii.