【作者】 张杰；

【导师】 刘赛；

【作者基本信息】 青岛大学 ， 药理学， 2003， 硕士

【摘要】 目的： 研究扇贝裙边提取物—糖胺聚糖(SS-GAG)对内皮细胞损伤的保护作用，探讨SS-GAG的抗动脉粥样硬化(AS)作用机制。 方法： 1 采用体外培养人脐静脉内皮细胞(HUVEC)，建立氧自由基、多聚阳离子诱导的HUVEC的损伤模型，通过MTT比色法研究SS-GAG对HUVEC损伤和增殖活性抑制的影响。 2．采用Fenton体系造成体外培养HUVEC的氧化损伤，用化学方法观察SS-GAG对HUVEC损伤后乳酸脱氢酶(LDH)渗出的影响。 3．应用放射免疫方法，观察SS-GAG对Fenton体系所引发的HUVEC损伤后内皮素及血管紧张素Ⅱ分泌改变的影响。 4．运用酶联免疫吸附测定(ELISA)法，观察HUVEC受到Fenton体系所致的氧化损伤后，血管内皮细胞粘附分子-1(VCAM-1)表达的改变，以及SS-GAG对此改变的影响。 5．运用酶联免疫吸附测定(ELISA)法，观察HUVEC经Fenton体系氧化损伤后，血小板衍生生长因子B链(PDGF-BB)表达的改变，观察SS-GAG对此改变有否影响。 结果： 1．分别经Fenton体系、多聚赖氨酸作用的损伤对照组，内皮细胞增殖活性明显下降(P＜0.01)。而细胞经不同浓度的SS-GAG预先处理后，细胞活性的损伤明显减轻(P＜0.05)，高剂量的SS-GAG保护组内皮细胞增殖活性明显高于低剂量组(P＜0.05)。 2．经Fenton体系介导的氧自由基损伤后，HUVEC培养液中LDH渗出明显增多，经SS-GAG预处理后，LDH渗出量明显减少(P＜0.01)。 3．SS-GAG保护组与经氧自由基损伤的损伤对照组对比，内皮素的分泌明显减少(P＜0.01)，且随SS-GAG剂量增加而降低；SS-GAG保护组与经氧自由基损伤的损伤对照组对比，血管紧张素Ⅱ的分泌也明显减少(P＜0.01)，高剂量的SS-GAG组的血管紧张素Ⅱ的分泌量低于低剂量组(P＜0.01)。 4．经SS-GAG保护的HUVEC表达VCAM-1的量，较氧自由基损伤的损伤中文摘要对照组明显减少(P<0.01)。 :5 55一GAG保护的HUvEC表达PDGF一BB的量，较Fenion体系作用的损伤对照组明显减少(P<O，05)。结论: s$GAG可减少Fenton体系及多聚赖氨酸介导的氧自由基及多舞阳离子对血管内皮细胞损伤，抑制血管内皮细胞对内皮素和血管紧张素n的分泌，减少血管内皮细胞VCAM一1、PDGF一BB的表达。表明55一GAG对血管内皮细胞的损伤有良好的保护作用，提示 55一GAG的抗动脉粥样硬化机制可能与其保护内皮细胞免受损伤、抑制损伤的血管内皮细胞分泌内皮素和血管紧张素n、使vCAM‘l、PDGF一BB的表达增强有关。更多还原

【Abstract】 Objective To investigation the protective action of the extract of scallop skirt-glycosaminoglycan(SS-GAG) on the endothelial cell , and to discuss it’s mechanism of anti-atherosclerosis(AS).Methods 1. The endothelial cell of human umbilical vein had been cultured in vitro, and induced by oxygen-derived free radidicals or polycatholyte , then the damage model had been established. MTT chromatometry was used to study the anti-effect of SS-GAG on the endothelial cell damage and proliferation activity.2. Oxidative damage to vascular endothelial cell was caused by Fenton reaction, to observe the effect of SS-GAG on the lactate dehydrogenase(LDH) secret of the endothelial cell.3. To observe the action of SS-GAG on the secret of endothelins and angiotensin II in the Fenton architecture by the means of radio-immunity.4. The effect on the expression of vascular cell adhesiveness molecul-1(VCAM-1) and platelet derivation growth factor(PDGF-BB) had been observed by the means of ELISA after the endothelial cell oxidizing damage had been caused by Fenton architecture.Results 1.In positive groups, polylysine, damaged by Fenton reaction , the endothelial cell proliferation dereased remarkably (P<0.01) . While pretreated by SS-GAG, cell proliferation damages lowered obviously (P < 0.05 ) , and cell proliferation in large dose SS-GAG protective control groups was higher than that in less dose control groups (P<0.05) .2. LDH excretion of the endothelial in HUVEC cellculture medium increased remarkably when the endothelial cell damaged by oxygen-derived free radidicals induced by Fenton reaction, but it decreased remarkably when pretreated by SS-GAG(P<0.01) .3. Compare with positive control group damaged by oxygen-derived free radidicals , the excretion of endothelins decreased remarkably in SS-GAG group (P<0.01) , and decreased with increase of SS-GAG dose. After damaged by oxygen-derived free radidicals, the excretion of angiotensin II in HUVEC rised obviously (P<0.01) .Anpotensin II excretion in large dose SS-GAG protective control groups was less than that in small dose control groups (P<0.01) .4. Compare with positive control group, the number of VCAM-1 expression descended obviously in SS-GAG groups (P<0.01) .5. Compare with positive control group, the number of PDGF-BB expression descended obviously in SS-GAG groups (P<0.05) .Conclusion SS-GAG can reduce the endothelial cell damage caused by oxygen-derived free radidicals or polycatholyte, can restrain the excretion of endothelins and angiotensin II, and reduce the expression of VCAM-1 and PDGF-BB. These indicate SS-GAG has satisfactory protection effect on the endothelial cell damage, and suggest the antiatherosclerosis mechanism of SS-GAG may has relation to its protection on the endothelial cell, its inhibition of endothelins and angiotensin II excretion, and reduction of VCAM-1 and PDGF-BB expression.更多还原