藤黄酸通过阻抑表皮生长因子受体酪氨酸磷酸化抑制大鼠主动脉平滑肌细胞增殖

目的 探讨藤黄酸对表皮生长因子诱导大鼠主动脉平滑肌细胞增殖的作用及其机制.方法 CCK8法和3H-胸腺嘧啶掺入法检测不同浓度藤黄酸(0.25、0.5、1.0及2.0 μmol/L)对表皮生长因子诱导的血管平滑肌细胞增殖的影响,流式细胞仪检测不同浓度藤黄酸对表皮生长因子诱导的细胞周期转换的影响,Western blotting检测不同浓度藤黄酸对表皮生长因子诱导的表皮生长因子受体和酪氨酸磷酸化的作用,斑点结合检测藤黄酸是否在体外表皮生长因子结合进而影响其活性.结果 藤黄酸抑制表皮生长因子诱导的血管平滑肌细胞增殖和DNA合成,藤黄酸抑制表皮生长因子诱导的血管平滑肌细胞周期的演进,藤黄酸抑制表皮生长因子受体和酪氨酸磷酸化,表皮生长因子在体外并不与藤黄酸结合.结论 藤黄酸通过对表皮生长因子受体磷酸化的抑制进而抑制表皮生长因子诱导的血管平滑肌细胞增殖,这种抑制可能是通过直接抑制酪氨酸磷酸化引起的,而不是通过藤黄酸与表皮生长因子受体结合引起的.     

Autoimmune Hepatitis Induced by Syngeneic Liver Cytosolic Proteins Biotransformed by Alcohol Metabolites

Background and aims: Aldehydes that are produced following the breakdown of ethanol (acetaldehyde) and lipid peroxidation of membranes (malondialdehyde) have been shown to bind (adduct) proteins. Additionally, these two aldehydes can combine (MAA) on nonsyngeneic and syngeneic proteins to initiate numerous immune responses to the unmodified part of the protein in the absence of an adjuvant. Therefore, these studies provide a potential mechanism for the development of antigen‐specific immune responses resulting in liver damage should syngeneic liver proteins be adducted with MAA. Methods: This study sought to test whether MAA‐modified syngeneic liver cytosolic proteins administered daily in the absence of adjuvant into C57BL/6 mice abrogates tolerance to initiate a MAA‐induced autoimmune‐like hepatitis. Results: In mice immunized with MAA‐modified cytosols, there was an increase in liver damage as assessed by aspartate aminotransferase/alanine aminotransferase levels that correlated with liver pathology scores and the presence of the pro‐fibrotic factors, smooth muscle actin, TGF‐β, and collagen. IgG antibodies and T‐cell proliferative responses specific for cytosolic proteins were also detected. Pro‐inflammatory cytokines were produced in the livers of animals exposed to MAA‐modified cytosols. Finally, transfer of immunized T cells to naïve animals caused biochemical and histological evidence of liver damage. Conclusions: These data demonstrate that a disease with an autoimmune‐like pathophysiology can be generated in this animal model using soluble MAA‐modified syngeneic liver cytosols as the immunogen. These studies provide insight into potential mechanism(s) that the metabolites of alcohol may play in contributing to the onset of an autoimmune‐like disease in patients with alcoholic liver disease.     

转化生长因子β在支气管哮喘气道平滑肌重塑中的作用

支气管哮喘(简称哮喘)是一种气道慢性炎症,持续的气道炎症导致气道重塑、不完全可逆的气流受限和进行性的肺功能受损.平滑肌细胞的增殖(包括增生和肥大)是哮喘气道重塑的特征性改变,是哮喘气道反应性和严重程度相关的重要因素之一.转化生长因子β(TGF-β)能够诱导分化、炎症、增生以及凋亡等多种细胞反应,促进平滑肌细胞的增生、肥大和迁移,在气道重塑中发挥重要作用.减少TGF-β的产生以及控制TGF-β的效应有利于对慢性哮喘气道重塑的干预治疗.     

Difference of climbing fiber input sources between the primate oculomotor-related cerebellar vermis and hemisphere revealed by a retrograde tracing study

The cerebellar flocculus–paraflocculus complex, vermal lobule VII (V-7) and hemispheric lobule VII (H-7) are involved in learning-dependent smooth pursuit eye movement control. To locate the sources of climbing fiber inputs to the H-7 and V-7, we injected retrograde tracers and examined the locations of retrogradely labeled neurons in the inferior olive in 4 monkeys. After the injection of cholera toxin B (CTB) into the H-7, retrogradely labeled neurons were observed abundantly in cell group d, i.e., dorsal cap, of the caudal medial accessory olive (MAO) and ventral lamella of principal olive (PO). After injections of fast blue (FB) into the V-7, retrogradely labeled neurons were observed mainly in cell group b of MAO, but rarely in cell group d or PO. Cell group d is known to receive inputs from the nucleus optic tract (NOT) and project climbing fibers to the flocculus and ventral paraflocculus, and cell group b is known to receive inputs from the superior colliculus. These results suggest that the three oculomotor cerebellar areas may use different visual signals for the control of smooth pursuit: the flocculus–paraflocculus complex and H-7 receive visual climbing fiber inputs derived mainly from the NOT via cell group d, while the V-7 receive visual climbing fiber inputs derived mainly from the superior colliculus via cell group b.     

全生物化组织工程血管的体外构建

目的 探讨组织工程血管的体外构建:脱细胞血管基质的制备.血管平滑肌细胞和血管内皮祖细胞的体外诱导培养和种植方法.方法 处理猪胸主动脉来获得脱细胞血管基质,采用二步种植法先后种植体外培养的平滑肌细胞和内皮细胞.结果 动脉管壁细胞全部脱除,脱细胞基质胶原蛋白含量与新鲜动脉相似,胶原纤维、弹性纤维呈网状排列,无断裂,基质保持完好.脱细胞血管基质的极限应力比新鲜动脉绀织减小20%[新鲜动脉:(1.1510±1.2870)×10-2,脱细胞血管基质:(0.9215±1.7000)×10-2,t=34.137,P<0.01].种植的平滑肌细胞和内皮细胞生长良好.结论 平滑肌细胞和内皮细胞种植于脱细胞血管基质后生长良好,可体外构建组织工程血管.     

同型半胱氨酸诱导人血管平滑肌细胞氧化损伤的研究

目的探讨同型半胱氨酸（Hcy）对人脐静脉血管平滑肌细胞（VSMCs）氧化损伤的作用及机制。方法用含不同剂量Hcy（50～1000μmol/L）的培养基培养VSMCs24h后,以分光光度比色法分别测定细胞内丙二醛（MDA）含量和超氧化物酶（SOD）、过氧化氢酶（CAT）活力的改变。结果随Hcy浓度增加,VSMCs内MDA的含量明显增加,SOD和CAT的活力也显著升高。Hcy明显促进了VSMCs的氧化。结论Hcy可直接诱导VSMCs的氧化损伤。     

通脉宁对AngⅡ及LPC诱导的血管平滑肌细胞内钙超载的影响

目的观察通脉宁全方及拆方药物血清对AngⅡ及LPC诱导的血管平滑肌细胞内钙超载的影响.方法组织贴块法进行血管平滑肌细胞(VSMC)培养,应用血清药理学研究的方法,AngⅡ 10-6mol/L、LPC 10-8mol/L作为刺激因子,制备通脉宁全方、益气拆方、活血拆方药物血清.采用Fluo-3染色荧光探针标记测定钙离子荧光强度.结果通脉宁全方及拆方药物血清对AngⅡ及LPC诱导的VSMC内钙超载具有明显的干预作用,且通脉宁全方组的干预作用明显优于益气拆方组及活血拆方组.结论通脉宁药物血清抑制AngⅡ及LPC诱导的VSMC增殖与部分阻断AngⅡ及LPC细胞内的信号转导途径有关,这可能是通脉宁抑制VSMC增殖的作用途径之一.     

苯并[a]芘诱导小鼠腹主动脉瘤形成机制研究

目的：探讨香烟烟雾重要成分苯并[a]芘（BaP）诱导小鼠腹主动脉瘤（AAA）形成的相关机制。方法48只7~9月龄C57BL/6N小鼠分为对照组、血管紧张素Ⅱ（AngⅡ）组、BaP组、AngⅡ/BaP复合物组。5周后取各组小鼠腹主动脉观察大体标本形态,切片行HE染色观察血管结构;免疫组化法检测各组靶血管基质金属蛋白酶-3（MMP-3）、核转录因子-κappaB（NF-κB）的表达, POD法TUNEL检测血管平滑肌细胞凋亡情况。结果大体标本显示AngⅡ/BaP复合物组腹主动脉瘤形成率为41.67%,明显高于AngⅡ组腹主动脉瘤形成率25.00%（P＜0.05）,HE染色提示动脉瘤形成处弹性纤维紊乱血管壁显著变薄。免疫组化提示AngⅡ/BaP复合物组MMP-3及NF-κB的表达均较AngⅡ组及BaP组增加[（0.48±0.13）% vs （0.24±0.16）%,（0.34±0.10）%;（0.42±0.12）% vs（0.23±0.06）%,（0.32±0.09）%,均P＜0.05]。AngⅡ/BaP复合物组平滑肌细胞凋亡较AngⅡ组及BaP组更明显[（30±12）%vs（19±5）%,（23±4）%,均P＜0.05]。结论 BaP在AngⅡ协同作用下可促进老龄C57BL/6N小鼠形成AAA,其机制可能与BaP通过NF-κB促进MMP-3的表达使弹性纤维紊乱及平滑肌细胞凋亡有关。