血清APE1蛋白检测在食管癌诊断中的价值

目的探讨血清脱嘌呤/脱嘧啶核酸内切酶1(APE1)蛋白检测在食管癌诊断中的价值。方法利用酶联免疫吸附试验(ELISA)法检测297例食管癌患者(病例组)和312例体检健康者(对照组)血清APE1蛋白水平,蛋白芯片法检测2组人群的癌胚抗原(CEA)、糖类抗原19-9(CA19-9)、糖类抗原242(CA242)水平,使用Logistic回归和受试者工作特征曲线(ROC曲线)分析,将APE1与CEA、CA19-9、CA242联合检测探讨其在食管癌诊断中的价值。结果 297例食管癌患者血清APE1中位水平为0.322 6ng/mL,显著高于对照组(P0.001)。APE1的ROC曲线下面积为0.661,灵敏度为50.2%,特异度为91.9%。APE1与CEA、CA19-9、CA242联合检测,灵敏度及准确度有所升高。结论血清APE1蛋白对食管癌的诊断具有辅助作用,与CEA、CA242、CA19-9联合检测可提高对食管癌的检出率。     

膀胱移行细胞癌组织APE1与VEGF表达及意义

目的探讨膀胱移行细胞癌组织中脱嘌呤脱嘧啶核酸内切酶-1（APE1）与血管内皮生长因子（VEGF）的表达及其临床意义。方法应用免疫组织化学方法检测55例膀胱移行细胞癌和15例正常膀胱黏膜中APE1及VEGF的表达。结果55例膀胱移行细胞癌组织中均有APE1蛋白表达,正常膀胱黏膜有8例表达（53.3%）,二者比较差异有显著性（χ^2=28.52,P〈0.01）。膀胱移行细胞癌APE1蛋白细胞浆与细胞核共表达27例（49.1%）,正常膀胱黏膜0例,二者比较差异有显著性（χ^2=11.99,P〈0.01）。VEGF在正常膀胱黏膜和膀胱移行细胞癌表达的阳性率分别为0和67.3%,差异有显著性（χ^2=21.41,P〈0.01）。随病理分级及临床分期的增加,膀胱移行细胞癌中APE1蛋白细胞浆和细胞核共表达的比例有增加趋势,差异有显著性（χ^2=7.73～11.25,P〈0.01）;APE1在细胞浆中的表达与VEGF表达呈显著正相关（r=0.458,P〈0.01）。结论APE1和VEGF可能在膀胱移行细胞癌发生发展中发挥重要的作用。     

APE1-AAbs水平与直肠癌患者病理学特征的关系及其诊断价值

目的探讨脱嘌呤脱嘧啶核酸内切酶(APE1-AAbs)表达与直肠癌患者病理学特征的关系及其诊断价值。方法选取2015年2月-2018年1我院确诊的直肠癌患者80例为直肠癌组、40例健康体检对象作为对照组,检测两组的APE1-AAbs表达水平,分析不同TNM分期、病灶直径、淋巴结转移情况、肿瘤分化程度的直肠癌患者血清APE1-AAbs表达水平,采用受试者工作曲线(ROC)分析APE1-AAbs诊断直肠癌的价值。结果直肠癌组患者的血清APE1-AAbs水平显著高于对照组,差异具有统计学意义(P0.05);血清APE1-AAbs水平鉴别诊断直肠癌的灵敏度为84.26%、特异度为71.54%、漏诊率为15.74%、误诊率为28.46%、ROC曲线下面积AUC值0.771;TNM分期(Ⅲ期+Ⅳ期)、低分化、发生淋巴结转移的直肠癌组患者的血清APE1-AAbs水平显著高于TNM分期(Ⅰ期+Ⅱ期)、高中分化、未发生淋巴结转移的患者,差异具有统计学意义(P0.05);不同年龄、性别、病灶直径的直肠癌患者血清APE1-AAbs水平差异均无统计学意义(P0.05)。结论检测血清APE1-AAbs水平对于直肠癌的诊断及病理学特征评估均具有一定的临床价值。     

NSCLC组织中Ape1/Ref⁃1及microRNA⁃21表达与预后关系

目的 探讨非小细胞肺癌(NSCLC)组织中脱嘌呤脱嘧啶核酸内切酶/氧化还原因子?1(Ape1/Ref?1)及微小RNA?21(microRNA?21)表达与化疗疗效及预后的关系.方法 选取2015年10月至2017年10月期间本院78例晚期NSCLC化疗患者组织及癌旁组织,均接受NSCLC标准一线化疗方案.比较Ape1...     

直肠癌患者术前新辅助化疗效果与血清APE1-AAbs和HIF-1α水平变化的关系

目的探讨直肠癌术前新辅助化疗效果与血清脱嘌呤脱嘧啶核酸内切酶1自身抗体(APE1-AAbs)和低氧诱导因子-1α(HIF-1α)水平变化的相关性。方法将2015年1月至2016年4月该院接诊的80例直肠癌患者纳入本研究,通过随机数表法分为观察组(n=40)和对照组(n=40),观察组在给予2个疗程的新辅助化疗后再实施手术,对照组术前不进行化疗直接实施手术。比较两组临床疗效、围术期情况、血清APE1-AAbs和HIF-1α的变化、术后并发症及复发率。结果观察组临床疗效总缓解率为52.50%,明显高于对照组的30.00%(P0.05);两组手术时间、术中出血量比较差异无统计学意义(P0.05);观察组术后排气时间、排便时间明显短于对照组且保肛率明显高于对照组(P0.05);治疗后,血清APE1-AAbs、HIF-1α较治疗前均显著降低(P0.05),观察组血清APE1-AAbs、HIF-1α水平明显低于对照组[(2.17±0.15)ng/mL vs.(2.48±0.17)ng/mL,(104.34±16.21)pg/mL vs.(147.94±17.52)pg/mL,均P0.05];两组尿路感染、吻合口瘘、吻合口出血、肠梗阻、尿潴留总发生率分别为22.50%、30.00%,差异无统计学意义(P0.05);1年的随访显示,观察组复发率为10.00%,明显低于对照组的30.00%(P0.05)。结论直肠癌患者术前给予新辅助化疗效果显著,可明显提高疾病缓解率、保肛率,促进术后恢复,且可降低复发率,其内在机制可能与血清APE1-AAbs、HIF-1α水平降低相关。     

脱嘌呤/脱嘧啶核酸内切酶1在氧化应激介导大鼠肺微血管内皮细胞损伤中的调控作用

目的探讨脱嘌呤/脱嘧啶核酸内切酶1（APE1）在过氧化氢（H₂O₂）介导的大鼠肺微血管内皮细胞（PMVECs）氧化应激中的调控作用。 方法分离培养大鼠PMVECs并分成4组：对照组（未加H₂O₂）及各剂量H₂O₂组（终浓度分别为50、100、200 μmol/L的H₂O₂）。在H₂O₂刺激细胞24 h后检测细胞增殖活性、细胞内活性氧水平及APE1蛋白表达,同时检测100 μmol/ml的H₂O₂刺激细胞24、48、72 h后APE1蛋白表达并比较。另外利用慢病毒载体转染构建APE1过表达PMVECs,将其分成对照组（未加H₂O₂）,H₂O₂组（终浓度为100 μmol/L的H₂O₂）,H₂O₂+空载体转染组（100 μmol/L的H₂O₂刺激慢病毒空载体转染的细胞）及H₂O₂+APE1转染组（终浓度为100 μmol/L的H₂O₂刺激APE1过表达细胞）,并在24 h检测细胞活性氧水平及细胞增值情况。 结果不同剂量组H₂O₂刺激细胞24 h后,四组间细胞增殖活性、活性氧的水平和APE1蛋白表达相对值差异均有统计学意义（F = 80.238、445.608、547.566,P均< 0.001）。在100 μmol/L的H₂O₂刺激细胞0、24、48和72 h后,APE1蛋白表达相对值的比较有统计学意义（F = 422.324,P < 0.001）,且随时间增加APE1表达也逐渐下降[（0.781 ± 0.043）、（0.611 ± 0.026）、（0.407 ± 0.014）、（0.272 ± 0.013）,P均< 0.05]。在转染慢病毒载体后,H₂O₂组活性氧水平明显高于对照组[（86.4 ± 1.2）vs.（56.4 ± 0.9）,P < 0.05];而H₂O₂ + APE1转染组细胞活性氧水平较H₂O₂组显著下降[（66.8 ± 1.0）vs.（86.4 ± 1.2）,P < 0.05],细胞增殖活性明显增加[（0.209 ± 0.001）vs.（0.153 ± 0.001）,P < 0.05]。 结论H₂O₂刺激可导致APE1蛋白表达下降,而上调APE1表达可增加细胞增殖活性,并抑制活性氧的产生。因此,APE1可能具有减轻H₂O₂介导的大鼠PMVECs氧化应激反应的作用。     

健脑益智口服液在脑缺血再灌注损伤中的神经保护作用及其机制

目的 探讨健脑益智口服液在反复脑缺血再灌注损伤中的神经保护机制. 方法 实验分为空白对照组、假手术组、模型组、中药组.实验期间空白对照组、假手术组、模型组以蒸馏水灌胃,中药组以健脑益智口服液灌胃,用药 5 d后实施脑缺血再灌注术.手术后第 1,10天,小鼠断头取脑以测定超氧化物歧化酶( SOD)的活性、丙二醛、肿瘤坏死因子α( TNF-α)以及白细胞介素 1β( IL-1β)的表达. 结果 与对照组 (26.82± 3.58) mg/g相比,模型组鼠脑缺血再灌注后 SOD活性第 1天 (13.95± 4.52) mg/g 和第 10天 (15.82± 4.39) mg/g 明显降低,丙二醛、 TNF-α ,IL-1β含量显著升高.与模型组相比,健脑益智口服液能显著提高 SOD[(21.35± 4.07) mg/g]的活性 (F=16.56, q=3.29,P< 0.05),并降低丙二醛的水平 (F=81.88,q=34.61,P< 0.01).健脑益智口服液能显著下调小鼠大脑皮质 TNF-α (F=96.44,q=35.11,P< 0.01)和 IL-1β (F=38.30,q=40.92,P< 0.01)的水平. 结论 健脑益智口服液通过降低脑缺血再灌注后脑氧化反应以及 TNF-α和 IL-1β表达而起到神经保护作用.     

APE/Ref-1和CA IX在头颈部肿瘤中表达的临床意义

无嘌呤/无嘧啶核酸内切酶(apurinic/apyrimidinic endonuclase,APE/Ref-1)是人体内一种重要的多功能蛋白,它涉及细胞凋亡、肿瘤发生、神经系统退行性变等病理过程[1-3].     

红参麦冬复方注射液对烫伤大鼠心肌损害的影响及机制

目的:观察红参麦冬复方注射液对烫伤大鼠早期心肌损害的影响并探讨其机制。方法:实验于2005-07/12在遂宁市人民医院药剂科进行。选择健康Wistar大鼠45只,单纯随机分为正常对照组5只、烫伤对照组20只和参麦组20只,后2组动物背部92℃水浴18s,造成30%TBSAⅢ度烫伤模型。参麦组烫伤后立即腹腔注射10mL红参麦冬复方注射液1支(商品名参麦注射液,杭州正大青春宝药业有限公司产品,批号001015,10mL/支,含红参、麦冬各1.0g),烫伤对照组注射等量生理盐水。观察大鼠烫伤后6,12,24,48h后心肌组织病理变化,检测心肌组织丙二醛浓度、超氧化物歧化酶活性及血清肿瘤坏死因子α水平(ELISA法)、乳酸脱氢酶(分光光度法)、肌酸激酶(分光光度法)水平,免疫组化法检测心肌热休克蛋白70蛋白表达变化。正常对照大鼠不经任何处理,过量麻醉后取材检测作支持对照。结果:45只大鼠全部进入结果分析。①烫伤对照组心肌细胞出现了变性坏死,参麦组在各时相点心肌病理变化均较烫伤对照组轻。②心肌组织丙二醛浓度:烫伤对照组在烫伤后各时相点均高于正常对照组,参麦组大鼠烫伤后6,12,24,48h丙二醛浓度只有烫伤对照组的57.7%,47.1%,49.3%和45.4%。③心肌组织超氧化物歧化酶活性:烫伤对照组大鼠烫伤后各时相点均低于正常对照组(P<0.01),参麦组则高于同时相点烫伤对照组(P<0.01)。④心肌组织热休克蛋白70蛋白表达:参麦组在烫伤后6,12,24,48h表达均高于烫伤对照组(0.445±0.041,0.436±0.034;0.847±0.078,0.608±0.055;0.997±0.91,0.818±0.045;1.147±0.148,0.769±0.045,P<0.01)。⑤血清血清肿瘤坏死因子α水平:参麦组在烫伤后6,12,24,48h均低于烫伤对照组[(3.14±0.31),(3.62±0.33)μg/L;(4.25±0.48),(5.67±0.51)μg/L;(4.57±0.53),(6.16±0.55)μg/L;(3.24±0.29),(4.47±0.45)μg/L;P<0.01]。⑥参麦组血清乳酸脱氢酶、肌酸激酶活性显著低于烫伤对照组(P<0.01)。结论:红参麦冬复方注射液可减轻大鼠烫伤后早期心肌损害,可能与减轻大鼠烫伤后心肌组织脂质过氧化反应程度以及减轻炎性因子水平有关。     

清除血液中内毒素、肿瘤坏死因子和白细胞介素-1对实验性内毒素休克时肺损伤的保护作用

目的：了解内毒素（ＬＰＳ）、肿瘤坏死因子（ＴＮＦ）和白细胞介素１（ＩＬ１）对实验性内毒素休克时肺损伤的保护作用。方法：实验分３组：Ⅰ组为假灌流组，Ⅱ组、Ⅲ组大鼠在内毒素休克早期开始分别给予活性炭（Ⅱ组）、大孔树脂ＡｍｂｅｒｌｉｔｅＸＡＤ７（Ⅲ组）血液灌流，结果与Ⅰ组作比较。结果：Ⅱ组ＬＰＳ、ＩＬ１水平明显降低，而Ⅲ组ＴＮＦ水平明显降低。Ⅱ组、Ⅲ组外周血白细胞数分别为（４．０±０．４）×１０９／Ｌ和（３．９±０．４）×１０９／Ｌ，均明显高于Ⅰ组〔（３．１±０．２）×１０９／Ｌ〕，Ｐ均＜０．０１；支气管肺泡灌洗液（ＢＡＬＦ）中的白细胞数〔（８．５±０．１）×１０９／Ｌ，（８．９±０．１）×１０９／Ｌ〕、肺系数（０．６４±０．０６，０．６６±０．０６）以及肺组织浸润的中性分叶核粒细胞数（２９．６±７．９／ＨＰ，３４．５±４．１／ＨＰ）均明显低于Ⅰ组〔（１２．３±１．８）×１０９／Ｌ，０．７５±０．０７，４８．６±６．６／ＨＰ〕，Ｐ均＜０．０１或＜０．０５。Ⅱ组、Ⅲ组的肺组织学改变亦较Ⅰ组明显减轻。结论：清除血液中致病介质可能对内毒素休克时的肺损伤产生保护作用。     

电磁脉冲照射对小鼠脑组织氧化状态的影响及姜黄素的治疗作用

目的观察电磁脉冲（EMR）照射后小鼠脑组织超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px）、丙二醛（MDA）的变化及姜黄素的防护作用。方法40只小鼠随机分为空白对照组、单纯EMR组、EMR＋姜黄素低剂量（20mg／kg／d）组、中剂量（40mg／kg／d）组、高剂量（80mg／kg／d）组，每组8只。EMR组和EMR＋姜黄素组小鼠接受200kV／m的EMR照射，EMR＋姜黄素组小鼠同时每日给予不同剂量的姜黄素，5d后停止照射及给药，测定小鼠脑组织中SOD、GSH-Px、MDA的变化。结果与空白对照组比较，EMR照射组小鼠脑组织SOD与GSH-Px活性及MDA含量上升（均P〈0．05）；与单纯EMR组比较，EMR＋姜黄素中、高剂量组小鼠脑组织SOD与GSH-Px活性及MDA含量下降（均P〈0.05）。结论200kV／m的EMR照射可导致小鼠脑组织过氧化，姜黄素可通过其抗氧化作用有效治疗这种损伤，且效应呈一定的剂量依赖关系。     

Alterations of glomerular and extracellular levels of glutathione peroxidase in patients and experimental rats with diabetic nephropathy

To investigate the status and role of glutathione peroxidase (GPX) in diabetic nephropathy, we measured GPX in the plasma and urine of 14 patients with diabetic glomerulosclerosis (DGS) and measured glomerular GPX immunostaining in these patients and in rats with streptozotocin-induced diabetes of varying duration. Plasma GPX levels were significantly lower in DGS patients than in diabetic patients without nephropathy (P < .05) or normal controls (P < .01). Urinary GPX concentrations were also significantly lower in DGS patients than in diabetic patients without nephropathy or normal controls (both P < .05). Immunostaining of glomerular GPX was significantly less in DGS patients than in normal controls (P < .05) and was negatively correlated with the glomerular sclerosis score and the index of mesangial expansion. Serial examination of glomerular GPX in diabetic rats showed that immunostaining scores for glomerular GPX in rats were significantly lower than those in normal control rats after 1 and 3 months' duration of diabetes, and staining scores were also significantly lower in rats killed after 3 months of diabetes than in those killed after 1 week. In conclusion, our study demonstrates that GPX concentrations in plasma, urine, and glomeruli are decreased in individuals with DGS and that the immunostaining of glomerular GPX decreases progressively.     

Plasma total antioxidant capacity, lipid peroxidation, and erythrocyte antioxidant enzyme activities in patients with rheumatoid arthritis and osteoarthritis

OBJECTIVES: The metabolism of cells in inflammatory and noninflammatory arthritic joint diseases is subject to complex environmental controls. The aim of the present study was to investigate the total antioxidant capacity (TAC), levels of lipid peroxidation (LPO), and antioxidant enzyme activities in patients with rheumatoid arthritis (RA) and osteoarthritis (OA). DESIGN AND METHODS: Plasma levels of TAC, malondialdehyde (MDA), the activities of some erythrocyte antioxidant enzymes, as well as erythrocyte sedimentation rates (ESR) were estimated in patients with RA and OA and compared with controls. RESULTS: The plasma TAC levels were significantly lower in the RA group than the OA and control group (P < 0.05). Plasma MDA concentrations were significantly higher in patients with RA than those with OA and healthy subjects (P < 0.05). Erythrocyte GSH-Px and CAT activities were found to be significantly lower in patients with RA than those with OA and healthy subjects (P < 0.05, P < 0.05, respectively). However, there were no significant differences in erythrocyte SOD activities between the groups (P > 0.05). ESR were significantly higher in RA patients than in healthy subjects and patients with OA (P < 0.01). Moreover, there were significant negative correlations between TAC vs. MDA, ESR vs. TAC, and a positive correlation between ESR vs. MDA in the RA group (r = -0.398, P < 0.05; r = -0.422, P < 0.05; r = 0.530, P < 0.05, respectively). CONCLUSIONS: Our results demonstrated that levels of LPO are increased in patients with RA compared to patients with OA. In addition, plasma TAC levels are decreased in RA due to its inflammatory character. We conclude that detecting plasma TAC levels with this novel method may be used as a routine and rapid test to verify the levels of oxidative stress in RA. Furthermore, correlating TAC and LPO levels with acute phase reactants such as ESR may give some clues about disease activity in RA.     

Increased glomerular and extracellular malondialdehyde levels in patients and rats with diabetic nephropathy

Results from animal experiments have suggested that reactive oxygen species (ROS) play an important role in tissue damage associated with diabetes. To determine whether ROS are involved in patients with diabetic nephropathy, we measured the plasma and urinary levels of malondialdehyde (MDA), an important marker of lipid peroxidation, and assessed the immunoreactivity of MDA and superoxide dismutase (SOD) in glomeruli of patients and experimental rats with diabetic nephropathy. Both plasma and urinary MDA levels were significantly higher in patients with diabetic glomerulosclerosis (DGS) than those of diabetic patients without proteinuria, proteinuric patients without diabetes, and normal controls. In DGS patients, the plasma MDA was significantly correlated with urinary MDA (p<0.05). The urinary MDA, but not plasma MDA, was significantly correlated with the degree of glomerulosclerosis and the index of mesangial expansion (both p<0.01) in DGS patients. The immunostaining score of glomerular MDA and SOD were also significantly higher in DGS patients than in control kidneys. In rats with diabetes for more than one month, the glomerular immunostaining for both MDA and SOD were also significantly higher than in controls rats, and both were increased with the progression of diabetes. Our results suggest that oxidative stress is involved in the pathogenesis and the progression of DGS.     

Association between reduced low density lipoprotein oxidation and inhibition of monocyte chemoattractant protein-1 production in statin-treated subjects

Monocyte chemoattractant protein-1 (MCP-1) is essential in atherogenesis. Oxidized lipids regulate MCP-1 expression and release from mononuclear cells. In this study we investigated (1) whether statin therapy reduces lipopolysaccharide (LPS)-stimulated MCP-1 production in human whole-blood samples and (2) the relationships between in vitro low-density lipoprotein (LDL) oxidation and MCP-1 production. Fasting blood samples were obtained from 55 healthy nonsmoking adults with moderate hypercholesterolemia who were participating in a randomized double-blind 8-week trial comparing the effects of statin therapy with those of placebo on cytokine production. Samples were analyzed for resistance to copper-mediated LDL oxidation (lag time in minutes), as well as MCP-1- and interleukin-8 (IL-8)-stimulated production. Statin therapy reduced MCP-1 production (mean +/- SD) -161 +/- 399 pg/mL/mm 3 white cells) compared with 267 +/- 985 pg/mL/mm 3 in the placebo group, but changes were not different between active and placebo groups ( P = .13). Statin therapy also increased lag times (median [interquartile range]; 20.5 [7.0-51.2] minutes vs -17.0 [-5.3-16.5] minutes; P = .067 for group difference). Inhibition of MCP-1 production correlated with prolongation of lag time ( r = .46, P = .0056) in statin-treated subjects. Statin therapy reduced MCP-1 production in the whole blood of human subjects and these changes were correlated with improvement in LDL oxidative resistance.     

Apoptosis and oxidants in the heart

Cardiomyocyte (CM) apoptosis has been reported in a variety of cardiovascular diseases, including myocardial infarction, ischemia/reperfusion, end-stage heart failure, arrhythmogenic right ventricular dysplasia, and adriamycin-induced cardiomyopathy. The role of CM apoptosis in the development and progression of cardiac diseases merits further investigation. Cumulative evidence suggests that reactive oxygen species (ROS), which have been implicated in cardiac pathophysiology, can trigger myocyte apoptosis by up-regulating proapoptotic proteins, such as Bax and caspases, and the mitochondria-dependent pathway. These apoptotic proteins and pathways are inhibited by various antioxidants, as well as by overexpression of the antiapoptotic protein Bcl-2 by way of the antioxidant pathway. Detection of CM apoptosis with the terminal transferase-mediated DNA nick-end labeling assay alone has recently been questioned because of technical concerns regarding its sensitivity and specificity. Because CMs are mononuclear or binuclear, if only one nucleus or a certain percentage of fragmented nuclei is stained with TUNEL assay at the early stage of apoptotic cell death, it remains unknown whether this particular early apoptotic CM is still functionally active. The issue of TUNEL specificity further questions reports of high percentages of apoptotic CM nuclei (0.02%-35%) in the heart. Nevertheless, oxidative stress is a major apoptotic stimulus in many cardiovascular diseases and the process can be inhibited by antioxidants both in vitro and in vivo.     

Correlation between hyperbaric oxygen exposure pressures and oxidative parameters in rat lung, brain, and erythrocytes

OBJECTIVES: The oxygen toxicity risk of hyperbaric oxygen (HBO) treatment has long been of interest. However, there are no comprehensive articles describing the relationship between HBO protocols and oxidative parameters used clinically. The purpose of this study was to determine the effects of various HBO pressure modalities on the oxidative values of rat lung, brain, and erythrocytes. DESIGN AND METHODS: A total of 64 male Sprague-Dawley rats was randomly divided into 7 groups. Group A was used as a control. Groups C to G were subjected to 100% oxygen at a pressure of 1, 1.5, 2, 2.5, and 3 ATA (atmosphere absolute), respectively, for 2 h. Group B was exposed to normal atmospheric air at 3 ATA for the same duration. The rat's lung, brain, and blood were taken immediately after the exposure and thiobarbituric acid reactive substances (TBARS) and superoxide dismutase (SOD) levels were determined. RESULTS: Both TBARS levels and SOD activity increased concordantly with the pressure increase. Although a statistically significant change in TBARS levels started from 100% oxygen exposure at 1 ATA (normobaric), SOD activity was affected after 2 ATA. A significant correlation exists between exposure pressure and the aforementioned parameters. Ambient air exposure at 3 ATA did not affect any parameters besides the brain TBARS levels. CONCLUSIONS: It is clear that HBO exposure causes oxidative stress. The main reason for this effect seems to be exposure to pure oxygen, since pure high pressure has no significant effect on the aforementioned parameters. However, clinicians should use as low pressures as possible since all oxidative parameters appear to be directly proportional to the extent of HBO exposure.     

Ethyl pyruvate ameliorates acute alcohol-induced liver injury and inflammation in mice

Ethyl pyruvate dissolved in a calcium-containing balanced salt solution--Ringer's ethyl pyruvate solution (REPS)--ameliorates ileal mucosal hyperpermeability and decreases the expression of several proinflammatory genes when it is used instead of Ringer's lactate solution (RLS) to resuscitate mice from hemorrhagic shock. Herein, we sought to determine whether delayed treatment with REPS would be beneficial in a murine model of acute alcoholic liver injury associated with binge drinking. Mice were gavaged with 3 doses of ethanol (5 g/kg each dose) over a 12-hour period and then randomized to treatment with 3 intraperitoneal doses of REPS or RLS over 12 hours. Compared with sham-treated controls not subjected to alcohol intoxication, RLS-treated mice demonstrated histologic evidence of fatty change and piecemeal necrosis of hepatocytes in the liver, as well as a significant increase in the plasma concentration of alanine aminotransferase. Biochemical changes induced by alcohol administration included increased hepatic lipid peroxidation, nuclear factor-kappaB activation, and tumor necrosis factor-alpha messenger RNA expression. All of these alcohol-induced effects were ameliorated by treatment with REPS instead of RLS. These data support the view that treatment with REPS ameliorates the hepatic inflammatory response and decreases hepatocellular injury in mice subjected to acute alcohol intoxication.     

Proteome of H-411E (liver) cells exposed to insulin and tumor necrosis factor-alpha: analysis of proteins involved in insulin resistance

Insulin resistance may be modeled in H-411E liver cells in tissue culture with the use of the cytokine tumor necrosis factor-alpha (TNF-alpha) and insulin. This tissue-culture model nicely mimics IR in human type 2 diabetes mellitus. After incubation of liver cells in tissue culture with INS alone, TNF-alpha alone, and TNF-alpha plus insulin, as well as a control sample, liver-cell extracts were separated on 2D polyacrylamide-gel electrophoresis on the basis of isoelectric point and molecular weight. We analyzed the gel images with the use of PD Quest software (Bio-Rad Laboratories, Hercules, Calif) to identify differentially expressed protein spots (ie, up or down with insulin vs down or up with TNF-alpha plus insulin). In separate experiments, phosphorus-32 incorporation/autoradiography and phosphoprotein staining were used to characterize treatment-induced phosphorylations. Affected protein spots were identified with the use of peptide fingerprinting and matrix-assisted laser desorption ionization time of flight mass spectrometry. The first series of experiments identified 6 differentially expressed proteins: eukaryotic translation initiation factor-3, subunit 2, regulator of G-protein signaling-5, superoxide dismutase, protein disulfide isomerase A6, proteasome subunit-alpha type 3, and regucalcin. In addition, we observed changes in the phosphorylation of protein disulfide isomerase A6. A second series of experiments identified 7 additional proteins with significantly altered differential expression: cell-division protein kinase-4, kinogen heavy chain, carbonic anhydrase-7, E 3 ubiquitin protein ligase, URE-B1; Rab GDP dissociation inhibitor-beta, Rab GDP dissociation inhibitor-beta2, and MAWDBP. It can be seen that differentially expressed proteins, affected by treatment with insulin or with TNF-alpha plus insulin, include regulators of translation, protein degradation, cellular Ca ++ , G-proteins, and free-radical production. Although one cannot detail the mechanism or mechanisms of TNF-alpha induced IR from this data alone, it is easy to relate all of these proteins to a role in insulin signal transduction and, hence, insulin resistance.     

Pathogenic molecular mechanisms in an animal model of fulminant hepatic failure: rabbit hemorrhagic viral disease

In this study we sought to determine whether molecular mechanisms involved in the pathogenesis of fulminant hepatic failure are present in rabbits experimentally infected with rabbit hemorrhagic disease virus (RHDV). The activities of aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase, as well as bilirubin concentration, were found to be significantly increased 36 hours after infection. Infected animals also demonstrated significant decreases in factor VII activity, in the Fischer index, and in the deterioration of prothrombin time. The concentration of reduced glutathione was significantly decreased 36 hours after infection, and we noted a marked increase in the ratio of oxidized to reduced glutathione. Infected animals showed progressive decreases in liver activity of the antioxidant enzyme superoxide dismutase. Expression of hepatocyte growth factor and c-met was found to be progressively reduced from 24 hours after infection, during which time we detected no modification in messenger RNA (mRNA) levels of transforming growth factor (TGF)-alpha. TFG-beta 1 was overexpressed 24 and 36 hours after infection, and 36 hours after infection we detected a significant increase in TNF-alpha mRNA levels. Experimental RHDV infection also induced marked activation of nuclear factor-kappaB and a significant increase in inducible nitric oxide synthase mRNA levels from 24 hours after infection. Data obtained from this animal model support its usefulness in the investigation of potential novel therapeutical modalities aimed at neutralizing reactive oxygen species and hepatocyte growth inhibitors or enhancing hepatocyte responsiveness to mitogens.