二十二碳六烯酸抑制大鼠视网膜光感受器细胞凋亡

目的:观察二十二碳六烯酸(DHA)对N-甲基-N-亚硝基脲(MNU)所致视网膜光感受器细胞凋亡的影响,为其临床应用提供理论依据.方法:35只雌性SD大鼠随机分为7组,每组5只.除正常组外,其余各组均于出生后35 d开始灌胃,DHA组和造模组每日分别灌服含有一定量DHA的脱脂牛奶或等体积的脱脂牛奶,持续15 d后行腹腔注射MNU 40 mg/kg.分别于造模后12,24,48 h全麻后处死相应动物,取眼球行光镜观察及用末端脱氧核苷酸转移酶介导dUTP缺口末段标记(TUNEL)法检测各组大鼠视网膜细胞的凋亡.结果:光镜下显示中周部视网膜在造模后24 h开始出现光感受器细胞排列紊乱,少量核固缩,48 h后光感受器细胞已大量溶解,而DHA组光感受器细胞的形态均接近正常,仅见排列紊乱、稀疏.造模组光感受器细胞在造模后12,24,48h的凋亡百分率(AD分别为(5.3±1.1)％、(60.6±4.1)％、(97.1±1.9)％,DHA组在造模后12,24,48 h的AI分别为(4.3±1.4)％、(44.5±7.8)％和(78.7±5.8)％,24 h和48 h后造模组和DHA组间比较均有统计学差异(P＜0.05).结论:二十二碳六烯酸40 mg/(kg·d)可以有效抑制视网膜光感受器细胞的凋亡.     

Role of Nuclear Transcription Factor-κB in Endotoxin-induced Shock in Rats

To investigate the role of NF-κB in endotoxic shock in rats. the model of endotoxinshock rats was induced by intravenous infusion of lipopolysaccharidc (LPS). 1 h. 2 h. 4 h and 6 h after LPS injection, the activation of NF-κB in blood mononuclear cells and the content of TNF-α and IL-6 in plasma was detected by enzyme-linked immunoadsordent assay (ELISA). The level of mean arterial pressure (MAP) and the histopathological changes of lung and liver were also observed. The activation of NF-κB in mononuclear cells increased 1 h after LPS injection and reached its peak 2 h after the injection, and its level was higher than that of normal group. The level of TNF-α was increased 1 h after the infusion and peaked 2 h after the injection, and its level was higher than that of normal group after LPS infusion. The content of IL-6 increased gradually with time. the IL-6 level was higher than that of normal group after LPS injection. MAP was decreased gradually with time and its level was lower than that of normal group after LPS injection. Pathological examination showed that endotoxic shock could cause pulmonary alveolar hemorrhage, edema and infiltration of inflammatory cell in lung tissue and congestion, edema, capillary dilation and inflammatory cell infiltration in liver tissue. It is concluded that NF-κB can up-regulate the expression of TNF-α and IL-6 in plasma and play an important role in endotoxin induced shock in rats.     

Change and significance of nuclear factor-κB in adriamycin induced cardiomyopathy in rats

Background This study aimed at investigating the change and significance of nuclear factor-κB (NF-κB) in eardiomyopathy induced by adriamyein (ADR) in rats. Methods Sixty male Wistar rats were randomly divided into three groups: control, ADR and ADR pyrrolidine dithiocarbamate (PDTC) groups. After 30-day experiment, myocardial histopathological observation was performed. Location and distribution of NF-κB p50 was examined by immunohistochemical assay. Expression of NF-κB p50 protein was examined by immunoboh assay. Electrophoretic Mobility Shift Assay examined activity of NF-κB; Myocardium p53 gene expression was examined by RT-PCR analysis. Results The myocardial lesions of rats were less pronounced in ADR PDTC group than in ADR group. Compared with control group, there were many myocardium nucleuses, which expressed NF-κB p50 and distribute under epicardium. Expression of NF-κB p50 protein in nucleus increased significantly in ADR group. The NF-κB binding activity increased significantly in ADR group. Myocardium expressions of p53 mRNA increased in ADR group. Conclusions The NF-κB binding activity increased significantly in cardiomyopathy induced by ADR in rats. Moreover, NF-κB plays an important role in causing degeneration of myocardial tissue and regulating expression of related-apoptosis genes.     

Inducing apoptosis and upregulation of Bax and Fas ligand expression by allicin in hepatocellular carcinoma in Balb/c nude mice

Many health benefits have been ascribed to allicin, including vasorelaxant activities. However, the molecular mechanisms underlying these effects remain unknown. To apply allicin in clinical anti-HCC treatment, different doses of allicin and Adriamycin （ADM） were led into transplanted tumor model established by injecting HCC BEL7402 cells into subcutaneous tissue of nude mice. Treatment with allicin and ADM resulted in tumor regression with inducing of Bax and Fas ligand （FasL） mRNA.     

Inhibition of tumor necrosis factor-α reduces alveolar septal cell apoptosis in passive smoking rats

Background Recent studies have revealed that lung cell apoptosis plays an important role in pathogenesis of cigarette-induced chronic obstructive pulmonary disease （COPD）. Tumor necrosis factor alpha （TNF-α） is one of the most important cytokines which are involved in COPD. This study aimed at investigating the influence of its inhibitor, recombinant human necrosis factor-alpha receptor II：lgG Fc fusion protein （rhTNFR：Fc） on alveolar septal cell apoptosis in passive smoking rats. Methods Forty-eight rats were randomly divided into a normal control group, a passive smoking group, an rhTNFR：Fc intervention group and a sham intervention group. The passive smoking rats were treated by exposure to cigarette smoking daily for 80 days. After smoking for one month the rhTNFR：Fc intervention group was treated with rhTNFR：Fc by subcutaneous injection, the sham intervention group injected subcutaneously with a neutral preparation （normal saline 0.1 ml, manicol 0.8 ml, cane sugar 0.2 mg, Tris 0.024 mg as a control. Lung function was determined and the levels of TNF-a in serum and broncho-alveolar lavage fluid （BALF） were measured with enzyme-linked immunosorbnent assay （ELISA）. Lung tissue sections stained by hematoxylin and eosin （HE） were observed for study of morphological alternations. Mean linear intercept （MLI） and mean alveolar numbers （MAN） were measured and the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling （TUNEL） method was carried out to determine the percentage of positive cells and distribution of apoptotic cells. Results Increased MLI and decreased MAN were found in the passive smoking group compared with both the normal control group and the rhTNFR：Fc intervention group （P〈0.05）. Forced expiratory volume in 0.3 second （FEVo.3）/forced vital capacity （FVC） and peak expiratory flow （PEF） were lower in the passive smoking group than that in the normal control group （P〈0.05）. Compared with the sham intervention group     

NF-κB/IκBα在MNU致实验性大鼠视网膜损伤中的变化

目的 观察核因子KappaB（NF-κB）在N-甲基-N-亚硝脲（MNU）诱导大鼠视网膜光感受器细胞凋亡中的的变化,探讨MNU损伤视网膜的机制。方法 给生后50d的雌性SD大鼠一次腹腔注射MNU60mg／kg．分别在MNU处理不同时间后处死动物。光学显微镜观察视网膜的形态学变化;TUNEL试剂盒检测光感受器细胞凋亡：Western blotting分析NF-κB。结果 MNU处理后24h,视网膜光感受器细胞核固缩和光感受器细胞层外节部定向障碍：7d后．外颗粒层和光感受层几乎完全消失。光感受器细胞凋亡在MNU处理后24h达高峰。在凋亡发生的过程中,仅在MNU作用12h和24h后,胞核内有低水平的p65蛋白。相反,胞浆和胞核内的KB蛋白水平呈时间依赖性地显著增加。结论 NF-κB／IKBa信号通路的激活可能介导了MNU所致的视网膜损伤。     

大鼠坐骨神经损伤后脊髓运动神经元凋亡及其机制研究

目的探讨大鼠坐骨神经损伤后雪旺细胞（schwann cells，SCs）中核因子-κB（nuclear factor-kappa B,NF-κB）的表达及其对脊髓运动神经元凋亡的调控作用。方法健康成年雄性SD大鼠36只，体重200～250g，随机分为正常对照组（n=-6）和坐骨神经钳夹损伤组（n=30）。采用免疫组化、计算机图像分析技术，对正常和损伤后不同时间1、3、7、14及21d的坐骨神经SCs中NF—κB的表达进行检测。同时取与坐骨神经相连的L4～L6段脊髓作原位末端标记技术（TUNEL）检测脊髓运动神经元的凋亡。结果与正常对照组相比较，损伤组坐骨神经SCs中NF—κB的表达显著改变，其变化趋势为先升高后降低，伤后3d达高峰。随后逐渐下降，21d接近正常值；损伤组脊髓运动神经元凋亡数在损伤后表现出相同的变化趋势。相关分析表明两者呈显著正相关。结论坐骨神经损伤后脊髓运动神经元发生不同程度的凋亡，SCs中NF—κB可能参与这种凋亡的调控过程。     

Expression of NF-kB in Schwann apoptosis in spinal cord following cells and its effect on motor neuron sciatic nerves injury in rats

Objective：To explore the expression of nuclear factor-kappa B （NF-kB） in Schwann cells （SCs） and its effect on motor neuron apoptosis in spinal cord following sciatic nerves injury in adult rats. Methods： Thirty-six adult Sprague-Dawley （SD） rats were divided randomly into normal control group （n=6）, and sciatic nerves crushing group （n= 30）, and the later was further equally randomized into 5 subgroups： 1, 3, 7, 14, and 21 d post-injury groups. The expression of NF-kB of normal and injured nerves were examined by immunohistochemistry staining, and the apoptosis of motor neurons in spinal cord of lumbar 4 to lumbar 6 （L4-L6） was investigated by terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling （TUNEL） assay. Both were qua.ntitated by image analysis. Results： In crushing group, except 21 d post-injury group, the expression of NF-kB was markedly higher than that in the normal control group （P〈0.05, P〈0. 01）. At 1 d after sciatic nerves crushing, the expression of NF-kB was obviously up-regulated, reached peak at 3 d, and recovered at 21 d. The same trend was observed in the time-course on motor neuron apoptosis after sciatic nerves injury. Correlation analyses revealed that motor neuron apoptosis was significantly and positively correlated with the expression of NF-kB following sciatic nerves injury （r= 0. 976 0, P〈0. 01）. Conclusion： After injury of sciatic nerves, the presence and up-regulation of NF-kB in SCs may be involved in motor neuron apoptosis in L4-L6 spinal cord.     

感染性休克大鼠心功能改变及心肌细胞中核因子-κB的表达

目的观察感染性休克大鼠心功能的改变及心肌细胞中核因子-κB(NF-κB)的表达。方法将20只大鼠随机分为2组,每组10只。实验组采用盲肠结扎穿孔术(CLP)制作感染性休克模型,对照组不进行CLP术,其余操作同实验组。2组均于12 h后测定心肌组织NF-κB蛋白表达及心功能情况。结果实验组心肌组织内NF-κB阳性表达明显高于对照组,差别有统计学意义(P<0.01);实验组大鼠左室内压上升下降最大速率、左心室收缩末期压、心率、收缩压及舒张压明显低于对照组,而左心室舒张末期压明显高于对照组,差别均有统计学意义(P<0.01)。结论CLP所致感染性休克大鼠心肌细胞中NF-κB蛋白表达升高可能与大鼠心功能减退有关。     

核因子-κB与感染性休克大鼠肝细胞凋亡的关系

目的探讨核因子-κB(NF-κB)与感染性休克大鼠肝细胞凋亡的关系,了解感染性休克时肝功能减退的机制。方法将20只大鼠随机分为2组,每组10只,实验组采用盲肠结扎穿孔术(CLP)制备感染性休克大鼠模型;对照组大鼠不进行盲肠结扎穿孔术。2组均测定肝脏细胞NF-κB蛋白、肝功能及肝细胞凋亡的情况。结果与对照组比较,实验组肝细胞凋亡指数明显升高(P<0.01),肝细胞中NF-κB蛋白表达明显增强,血清谷丙转氨酶和乳酸脱氢酶含量明显升高(P<0.01)。结论CLP所致的感染性休克过程中,NF-κB蛋白表达升高,可能导致肝细胞凋亡增加,以致肝功能减退。     

EFFECT OF OXIDIZED-LDL ON NF-κB NUCLEAR TRANSLOCATION IN AORTIC SMOOTH MUSCLE CELLS ORIGINATED FROM RATS OF DIFFERENT AGES

Objective To investigate the molecular mechanism of atherosclerosis that related to age. Methods Immunohistochemistry staining and Western blot were adopted to determine the nuclear translocation of nuclear factor-kappa B (NF-κB) and expression of platelet-derived growth factor B (PDGF-B) in smooth muscle cells(SMCs) co-cultured with low density lipoprotein (LDL), oxidized LDL (ox-LDL), and ox-LDL high density lipoprotein(HDL) originated fi‘om rats of 2 and l0 months old respectively. Fat stain was used to identify the lipid intake in SMCs. Results The optimal stimulation time ofox-LDL to SMCs was 12 hours. NF-KB intensity increased in most nuclei of SMCs that originated fi‘om rats of either 2 or l0 months old co-cultured with ox-LDL. The intensity of NF-KB and the amount of intracellular lipid taken in SMCs were more obvious in cells fi‘om 10-month-old rats than fi‘om the younger ones.Change of PDGF-B expression in SMCs was not remarkable in each group of rats. Conclusions The 10-month-old rats are more susceptive to ox-LDL than 2-month-old rats in activating nuclear translocation of NF-KB. Maybe this is one of the important reasons contributing to the difference between the older and younger rats on the initiation and development of atherosclerosis lesion. Expression of PDGF-B is not associated with the activity of nuclear translocation of NF-κB.     

核转录因子在动脉粥样硬化形成中的作用

目的了解核转录因子(NF-κB)家族及其与动脉粥样硬化(AS)关系的研究进展。方法复习国内外相关文献,综述NF-κB家族的组成、生物学特征及其在AS发生发展中的作用。结果NF-κB主要参与许多与炎症反应有关的基因的表达调控,在参与AS发生发展的血管平滑肌细胞、内皮细胞和巨噬细胞内均有NF-κB表达。结论NF-κB的激活可能是AS发生发展的始动机理之一,抑制NF-κB的活化,可望为AS的防治开辟新的途径。