芪苈强心胶囊对心力衰竭大鼠心肌线粒体蛋白质组影响的研究

目的采用蛋白质学方法研究芪苈强心（QLQX）胶囊对心力衰竭大鼠心肌细胞线粒体蛋白表达情况的影响,并探讨其治疗心力衰竭的机制。方法将心肌梗死心力衰竭大鼠模型分为心衰模型组、QLQX（1.0g/kg.d-1）胶囊组、假手术组。灌胃给药,每天一次,连续4周后,差速离心法提取心肌线粒体,双向电泳法分离差异表达的蛋白,凝胶银染后酶切差异蛋白点进行激光解析电离飞行时间（MALDI-TOF）质谱分析,通过Mascot软件在数据库检索。结果共鉴定出11种差异表达的蛋白质,表达上调的有NADH氧化还原酶、ATP合成酶、苹果酸脱氢酶、长链乙酰辅酶A脱氢酶、缩醛酶、肌酸激酶、58 kDa钙调蛋白;表达下调的蛋白有乳酸脱氢酶B、烯醇酶、αB2Crystallin和热休克蛋白27。结论 QLQX胶囊能够部分纠正衰竭心肌线粒体有关能量代谢、氧化应激相关酶的异常表达,可能是其治疗心力衰竭的机制之一。     

Phosphodiesterase-3 inhibitor （cilostazol） attenuates oxidative stress-induced mitochondrial dysfunction in the heart

Background Cilostazol is a type 3 phosphodiesterase inhibitor which has been previously demonstrated to prevent the occurrence of tachyarrhythmia and improve defibrillation efficacy. However, the mechanism for this beneficial effect is still unclear. Since cardiac mito-chondria have been shown to play a crucial role in fatal cardiac arrhythmias and that oxidative stress is one of the main contributors to arr-hythmia generation, we tested the effects of cilostazol on cardiac mitochondria under severe oxidative stress. Methods Mitochondria were isolated from rat hearts and treated with H2O2 to induce oxidative stress. Cilostazol, at various concentrations, was used to study its protective effects. Pharmacological interventions, including a mitochondrial permeability transition pore （mPTP） blocker, cyclosporine A （CsA）, and an inner membrane anion channel （IMAC） blocker, 4＇-chlorodiazepam （CDP）, were used to investigate the mechanistic role of cilostazol on cardiac mitochondria. Cardiac mitochondrial reactive oxygen species （ROS） production, mitochondrial membrane potential change and mi-tochondrial swelling were determined as indicators of cardiac mitochondrial function. Results Cilostazol preserved cardiac mitochondrial function when exposed to oxidative stress by preventing mitochondrial depolarization, mitochondrial swelling, and decreasing ROS produc-tion. Conclusions Our findings suggest that cardioprotective effects of cilostazol reported previously could be due to its prevention of car-diac mitochondrial dysfunction caused by severe oxidative stress.     

Early reversal cardiac with esmolol in hypertensive rats: The role of subcellular organelle phenotype

BackgroundOur group has previously shown that short-term treatment (48 h) with esmolol reduces left ventricular hypertrophy (LVH) in spontaneously hypertensive rats (SHRs). However, we do not know the mechanism that explain this effect. The aim of this study was to assess the role that the subcellular organelle phenotype plays in early cardiac reverse after short-term treatment with esmolol.Methods14-Month-old male SHRs were randomly assigned to receive esmolol (300 μg/kg/min) (SHR-E) or vehicle (SHR). Age-matched male Wistar-Kyoto rats (WKY) served as controls. After 48 h of treatment, an ultrastructural analysis of heart tissue (left ventricle) was performed. We studied cardiomyocyte ultrastructural remodeling of subcellular organelles by electronic microcopy in all groups.ResultsSHR group showed significant morphometric and stereological changes in mitochondria and subcellular organelles (cytoplasm and nucleus, myofibril structure, mitochondria structure, Z-Disk, intercalated disk, T-system and cystern), and also changes in the extracellular matrix (collagen) with respect to WKY group. Esmolol significantly improved the morphology and stereology mitochondrial, reduced the organelle phenotype abnormalities but no produced changes in the extracellular matrix with respect to SHR group. Interesantly, parameters of mitochondria (regularity factor, ellipsoidal form factor and density of volume), and all parameters of subcellular organelles returned to the normality in SHR-E.ConclusionOur results show that left ventricular hypertrophy reversal after short-term treatment with esmolol is associated with reversal of subcellular organelle phenotype.     

右美托咪定对大鼠离体肺缺血再灌注所致线粒体损伤的影响

目的：探究右美托咪定（dexmedetomidine,Dex）对大鼠离体肺缺血再灌注所致线粒体损伤的影响。方法：将SD大鼠随机分成4组（n=6）：对照组（C组）、缺血再灌注组（IR组）、1 nmol/L Dex组（D1组）、10 nmol/L Dex组（D10组）,制备大鼠离体肺缺血再灌注模型。记录平衡末（T0）、再灌注即刻（T1）、再灌注30 min（T2）和再灌注60 min（T3）时的潮气量（tidal volume,VT）、肺顺应性（compliance,Cdyn）、气道阻力（airway resistance,Raw）和肺静脉氧分压（oxygen partial,PaO2）;测定肺湿/干重比;HE染色观察组织病理学改变;测定灌流末流出液乳酸脱氢酶（LDH）活性和肺组织中活性氧（ROS）、丙二醛（MDA）、三磷酸腺苷（ATP）含量以及超氧化物歧化酶（SOD）活性。分离肺组织线粒体,检测线粒体肿胀程度和线粒体膜电位（MMP）。结果：与C组相比,IR组、D1组、D10组肺功能不同程度降低,LDH活性升高,ROS、MDA增加,SOD活性下降,ATP生成减少,线粒体肿胀程度升高,MMP下降（P < 0.05）;与IR组相比,D1组、D10组肺功能改善,病理显示肺损伤明显减轻,LDH释放减少,ROS、MDA含量减少,SOD活性升高,ATP生成增加,线粒体肿胀程度减轻,MMP上升（P < 0.05）;与D1组相比,D10组改善肺功能作用更明显,Raw下降,LDH活性降低,SOD活性升高,线粒体肿胀程度减轻（P < 0.05）。结论：右美托咪定减轻了离体肺缺血再灌注损伤,其机制可能与减轻线粒体损伤,减少氧化应激反应有关。     

人肺腺癌细胞系A549线粒体差异蛋白质组学研究

目的 研究人肺腺癌细胞系A549与人正常支气管上皮细胞系16HBE线粒体蛋白质组的差异表达.方法 传代培养细胞系A549及16HBE,用线粒体提取试剂盒获取细胞线粒体蛋白质,进行双向凝胶电泳,运用液相色谱串联质谱分析技术筛选出A549和16HBE细胞系线粒体间表达水平显著差异的蛋白,所得结果通过Data Analysis软件标峰,用MASCOT进行结果搜索和数据分析.结果 双向电泳结果显示A549、16HBE细胞系线粒体存在差异的蛋白质点共41个,3倍以上差异的16个,A549细胞系中表达上调的15个,表达下调的26个,其中3倍以上差异表达上调的7个,表达下调的9个.运用液相色谱串联质谱技术鉴定出A549细胞系线粒体表达上调的蛋白质2个:AAA+ ATP酶家族结构域蛋白3B、tRNA鸟嘌呤糖基转移酶,表达下调的蛋白质7个:热休克蛋白75、复合物Ⅲ亚基1、复合物Ⅲ亚基2、鸟氨酸氨基转移酶、异柠檬酸脱氢酶亚基α、SLP-2、抗增殖蛋白.结论 应用亚细胞蛋白质组学方法,鉴定出肺腺癌细胞系线粒体差异表达蛋白,为阐明肺腺癌发生的分子机制、筛选早期诊断标志物提供了有益的线索.     

Age-related changes in the rat brain mitochondrial antioxidative enzyme ratios: Modulation by melatonin

Oxidative stress is an important factor for aging. The antioxidative enzymes glutathione peroxidase (GPx), glutathione reductase (GRd) and superoxide dismutase (SOD) play a crucial role protecting the organism against the age-dependent oxidative stress. Glutathione (GSH) is present in nearly all living cells. GSH is one of the main antioxidants in the cell and it serves several physiological functions. Our purpose was to evaluate the age-related changes in mitochondrial GPx, GRd and SOD activities, and mitochondrial GSH pool in the brains of young (3months) and aged rats (24months). We also investigated whether melatonin administration influences these brain mitochondrial enzyme activities and GSH levels in young and aged rats. The results showed that GPx activity increased with age, whereas melatonin treatment decreased GPx activity in the aged rats at levels similar to those in young and young+melatonin groups. The activities of GRd and SOD, however, did not change with age. But, melatonin treatment increased SOD activity in the aged rats. GSH levels, which also increased with age, were not modified by melatonin treatment. The reduction in the SOD/GPx and GR/GPx ratios with age was prevented by melatonin administration. Together, our results suggest that the age-related oxidative stress in rat brain mitochondria is more apparent when the antioxidant enzyme ratios are analyzed instead of their absolute values. The antioxidative effects of melatonin were also supported by the recovery of the enzyme ratios during aging.     

Actions of 17β-estradiol and testosterone in the mitochondria and their implications in aging

A decline in the mitochondrial functions and aging are two closely related processes. The presence of estrogen and androgen receptors and hormone-responsive elements in the mitochondria represents the starting point for the investigation of the effects of 17β-estradiol and testosterone on the mitochondrial functions and their relationships with aging. Both steroids trigger a complex molecular mechanism that involves crosstalk between the mitochondria, nucleus, and plasma membrane, and the cytoskeleton plays a key role in these interactions. The result of this signaling is mitochondrial protection. Therefore, the molecular components of the pathways activated by the sexual steroids could represent targets for anti-aging therapies. In this review, we discuss previous studies that describe the estrogen- and testosterone-dependent actions on the mitochondrial processes implicated in aging.