Chemopreventive efficacy of pronyl-lysine on lipid peroxidation and antioxidant status in rat colon carcinogenesis

Colon cancer is a serious health problem in most of the countries and is the leading cause of cancer mortality throughout the world. The major objective of this study was to examine the chemopreventive effect of dietary pronyl-lysine (2 mg/kg body weight), a bread crust antioxidant, on intestinal and colonic tissue lipid peroxidation (LPO) and antioxidant status in rat colon carcinogenesis. Male Wistar rats were divided into seven groups and were fed a modified pellet diet for 34 weeks. Rats were given a weekly subcutaneous injection of 1,2-dimethyl hydrazine (DMH) (20 mg/kg body weight) for the first 15 weeks. Pronyl-lysine was supplemented to rats during the pre-initiation, initiation, post-initiation and also throughout the study period. All the rats were sacrificed at the end of 34 weeks and their colons were evaluated histologically. The activity of lipid peroxidation (LPO) and antioxidant status in the tissues such as the intestines, colon and cecum were estimated. Our results showed diminished levels of colonic, and cecal LPO products such as conjugated dienes, lipid hydroperoxides and thiobarbituric acid reactive substances, and also reduced activities of the antioxidants superoxide dismutase, catalase and glutathione dependent enzymes (glutathione peroxidase, glutathione-S-transferase, glutathione reductase) in DMH-treated rats, while on supplementing dietary pronyl-lysine the levels of LPO products and antioxidants were significantly reversed ( P  < 0.05). Thus, our results strongly suggest that the administration of pronyl-lysine throughout the study period (group 7) and the post-initiation (group 6) stages of colon carcinogenesis significantly inhibits colon cancer incidence and prevents DMH induced histopathological lesions.     

Protective role of luteolin on the status of lipid peroxidation and antioxidant defense against azoxymethane-induced experimental colon carcinogenesis

The modifying effect of dietary exposure to a flavonoid, luteolin (LUT) during the azoxymethane (AOM)-induced colon carcinogenesis was investigated in this study. Aberrant crypt foci (ACF), lipid peroxidation (LPO), enzymic and non-enzymic antioxidants and histopathological analysis were performed. Colon carcinogenesis was induced by injecting 15 mg/body kg weight of AOM, intraperitoneally (i.p.), once in a week for 3 weeks in male Balb/c mice. AOM-induced mice were treated with LUT (1.2 mg of LUT/kg body weight/day orally). After the experimental period, frequency of ACF, levels of thiobarbutaric acid reactive substances (TBARS) and hydroxy radical (OH˙) were found to be increased, whereas glutathione (GSH), Vitamins C, E and A were decreased in the plasma and colon of AOM-induced mice. However, LUT treatment to AOM-induced mice significantly decreased the incidence of ACF, levels of TBARS and OH˙ with a concordant increase in non-enzymic antioxidants in plasma and colon tissue. The activities of the antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) were found to be decreased due to the induction of colon cancer in mouse. LUT treatment ameliorated the activities of these antioxidant enzymes. The histological study revealed a significant increase in the enlarged nuclei and hyperchromatism of cells in AOM-induced mice whereas LUT significantly reduced the signs in the colon. The immunohistochemical expression of MDA-DNA adduct was studied. In AOM-induced group, the expression was increased and treatment with LUT decreased significantly. The present study depicts that LUT can act as an effective chemopreventive agent against colon cancer.     

Correlation of tissue lipid peroxidation and antioxidants with clinical stage and menopausal status in patients with adenocarcinoma of the breast

OBJECTIVES: To evaluate the extent of lipid peroxidation and the antioxidant levels in breast cancer patients in relation to different clinical stages and menopausal status. DESIGN AND METHODS: Fifty newly diagnosed women with adenocarcinoma of the breast were divided into different groups based on clinical staging and menopausal status. The extent of lipid peroxidation as reflected by the formation of thiobarbituric acid-reactive substances (TBARS), lipid hydroperoxides (LOOH), and conjugated dienes (CD) as well as the status of the antioxidants superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), and glutathione peroxidase (GPx) in tumor tissues and adjacent normal tissues were estimated in these patients. RESULTS: Enhanced lipid peroxidation accompanied by significant elevation in enzymatic and nonenzymatic antioxidants was observed in breast tumor tissues compared to the corresponding uninvolved adjacent tissues irrespective of clinical stage and menopausal status of the patients. The magnitude of change in tissue oxidant-antioxidant status was, however, more pronounced in stage III and in premenopausal patients compared to stage I and II and postmenopausal patients, respectively. CONCLUSION: A correlation between tissue redox status and tumor progression suggests that upregulation of antioxidants enables tumor cells to counter oxidative stress, thereby conferring a selective advantage for growth compared to corresponding normal cells.     

Redox status and lipid peroxidation in alcoholic hypertensive patients and alcoholic hypertensive patients with diabetes

Background: Free radical-mediated oxidative stress has been implicated in the progression of alcoholic hypertension and diabetic hypertension. Methods: The lipid peroxides and antioxidant status of plasma and erythrocytes were investigated in alcoholic hypertensive patients and alcoholic hypertensive patients with diabetes and compared with normal subjects. Results: A significant increase is observed in the levels of glucose, lipid peroxidation (P<0.05) in the alcoholic hypertensive patients with/without diabetes and the increase was significantly higher in alcoholic hypertensive patients with diabetes. The activities of erythrocyte antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and reduced glutathione (GSH) and plasma concentrations of GSH, vitamin C, vitamin E and β-carotene decreased significantly and the level of ceruloplasmin increased in alcoholic hypertensive patients with/without diabetes when compared to normal subjects. Plasma GSH and vitamin E levels exhibited a further decrease in alcoholic hypertensive patients with diabetes. Conclusions: An enhanced lipid peroxidation is observed in alcoholic hypertensive patients with diabetes and a more pronounced decrease in the levels of plasma GSH and vitamin E among antioxidants.     

Oxidative stress and antioxidant status in non-metastatic prostate cancer and benign prostatic hyperplasia

OBJECTIVES: We undertook the present study to investigate the possible alteration of oxidant/antioxidant status in the circulation of patients with prostate cancer and benign prostatic hyperplasia. DESIGN AND METHODS: Thiobarbituric acid reactive substances (TBARS), the enzyme activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT) and copper (Cu) and zinc (Zn) levels were estimated in the erythrocytes of 25 non-metastatic prostate cancer patients, 36 benign prostatic hyperplasia (BPH) patients and 24 age- and sex-matched healthy subjects (controls). RESULTS: TBARS concentrations were significantly increased, while erythrocyte GPX and SOD activities were significantly decreased in the prostate cancer group versus controls (P < 0.001) and BPH group (P < 0.05). Zn levels were lowered in prostate cancer patients versus controls (P < 0.01) with no significant changes between BPH and cancer groups. Similarly, lipid peroxidation was increased (P < 0.05) with decreased SOD activity and Zn level (P < 0.05) in BPH versus controls. CONCLUSION: These results reveal an alteration in the lipid peroxidation index, with concomitant changes in the antioxidant defense system in prostate cancer patients compared to BPH patients. We hypothesize that an altered prooxidant-antioxidant balance may lead to an increase in oxidative damage and consequently may play an important role in prostate carcinogenesis.     

The effect of bilirubin on lipid peroxidation and antioxidant enzymes in cumene hydroperoxide-treated erythrocytes

Recently, it has been suggested that bilirubin may act as a potent biological chain-breaking antioxidant. To observe the effects of free bilirubin on antioxidant reactions in cumene hydroperoxide-treated erythrocytes (15 g hemoglobin/dl), we added bilirubin at four different concentrations (0.5, 1, 5, and 10 mg/dl). We measured the thiobarbituric acid-reactive substance and reduced glutathione levels, and some antioxidant enzyme activities, namely superoxide dismutase, catalase, and glucose-6-phosphate dehydrogenase. Thiobarbituric acid-reactive substance and chemiluminescent signals decreased during the incubation. Superoxide dismutase activities also decreased but not as much as in the control group. Glucose-6-phosphate dehydrogenase activities and reduced glutathione levels increased, but catalase activities remained the same as the control group. Our results suggest that bilirubin — in the concentrations we have used — partially prevented the oxidant effects of cumene hydroperoxide.     

Evaluation of antioxidant and stabilizing lipid peroxidation nature of Solanum xanthocarpum leaves in experimentally diethylnitrosamine induced hepatocellular carcinogenesis

Solanum xanthocarpum Schrad. & Wendl, is a traditional edible leaves as a form of decoction, extracts used as a herbal medicine, and consumed for health promoting profiles. The present investigation was carried out to evaluate antioxidant status and lipid peroxidation level of anticancer activity of Solanum xanthocarpum (SXC) on Diethylnitrosamine (DEN) induced hepato carcinogenesis in male Wistar albino rats. Hepatic cancer was developed on the liver of Wistar rats treated by DEN or vehicle three times a week for 16 weeks. Tumour incidence, tumour volume, tumour burden, lipid peroxidation, antioxidant, liver marker enzymes and histopathological changes were assessed in DEN alone and in DEN + SXC leaves extract treated rats. Hundred percent tumour incidences with an imbalance in carcinogen metabolizing enzymes and cellular redox status were observed in rats treated with DEN alone. Oral administration of SXC aqueous leaves extract treatment at a dose of 150 mg/kg b.w. to DEN treated rats were prevented tumour incidence and restored the elevated activities of liver marker enzymes and antioxidant status to near normal with decreased lipid peroxide levels. The biochemical consistent with histopathological observations suggesting marked hepatoprotective effect of the leaves extract in a dose dependent manner. These results clearly suggest that SXC aqueous leaves extract treatment prevents liver damage, lipid peroxidation, protects the antioxidant defense system and anti-carcinogenic potential in DEN induced hepatic carcinogenesis.     

Oxygen-free radicals and lipid peroxidation in adult respiratory distress syndrome

Activated species of oxygen have been implicated as mediators of some acute lung injury. In adult respiratory distress syndrome (ARDS), polymorphonuclear leukocytes accumulate in the lung and release excessive amounts of O₂-derived products into the extracellular environment. The effects of these O₂ products on lung tissue are multiple. In particular, they can initiate lipid peroxydation in cellular membranes. Excessive lipid peroxydation in membranes destroys cells such as vascular endothelium. Lipid peroxides are also detrimental to cellular functions. Lipid peroxydation could then play a role in the pathogenesis of ARDS.     

宫颈癌患者淋巴结状态与预后的关系

目的分析宫颈癌患者淋巴结转移的特征及其对预后的影响。方法前瞻性研究手术治疗的宫颈癌患者311例,记录术中切除的淋巴结数量、部位、体积和病理结果,随访5年生存状况。结果 (1)311例患者淋巴结转移率23.8%,闭孔处转移率最高62.2%,主要沿宫旁淋巴结→闭孔→髂内、髂外→髂总→直肠旁→腹主动脉淋巴结引流途径顺次转移,3例为跳跃式转移。(2)在影响预后的多因素分析中,淋巴结转移(RR=3.524,95%CI:2.156-5.763)首先入选Cox回归模型。有、无淋巴结转移者的5年生存率分别为54.5%和86.1%(χ2=33.681,P<0.01)。(3)淋巴结转移个数和转移处数的风险比分别是2.441(95%CI:1.464-4.069)和2.484(95%CI:1.119-5.517),淋巴结转移数目≤3枚、4～10枚和>10枚者5年生存率分别是80.0%、57.6%和22.5%(χ2=14.340,P<0.01)。单处淋巴结转移和多处淋巴结转移者的5年生存率分别是72.0%和43.1%(χ2=5.887,P<0.05)。结论宫颈癌淋巴结转移主要沿淋巴引流途径进行,以闭孔处转移最常见。淋巴结转移状态是影响患者预后的最强因素,转移个数和转移处数越多,预后越差。     

孕期脂质过氧化作用与妊娠期糖尿病的相关性探讨

目的:研究妊娠期糖尿病(GDM)患者不同孕期体内脂质过氧化作用的变化,探讨脂质过氧化与GDM的相关性。方法:选择口服葡萄糖耐量试验诊断为GDM、经饮食治疗后血糖控制良好且足月分娩的31例单胎妊娠孕妇为研究对象,另选同期35名正常孕妇为正常对照组,分别采集妊娠中期、妊娠晚期和足月临产前的新鲜中段尿液,应用抗原标记酶联免疫法测定8-异前列腺素F2α(8-iso-PG2α)的水平,分析临床指标和妊娠结局与8-iso-PGF2α水平的相关性。结果:正常对照组妊娠中、晚期及足月临产前的尿8-iso-PGF2α水平比较差异无统计学意义(P>0.05);妊娠中期GDM组和正常对照组尿8-iso-PGF2α水平比较差异亦无统计学意义(P>0.05)。GDM组妊娠晚期和足月临产前尿8-iso-PGF2α水平比较差异无统计学意义,但较妊娠中期显著升高,同时也高于正常妊娠组(P<0.05)。GDM组足月临产前血细胞比容和血尿酸水平明显高于正常妊娠组并与足月临产前尿8-iso-PGF2α水平呈正相关(P<0.05),部分凝血活酶时间和凝血酶原时间明显低于正常妊娠组并与足月临产前尿8-iso-PGF2α水平呈负相关(P<0.05)。结论:妊娠过程中正常孕妇脂质过氧化作用保持稳定。GDM孕妇妊娠晚期脂质过氧化作用明显增强,饮食控制血糖水平正常者,异常增强的脂质过氧化作用仍未能恢复到正常水平。     

Amino acids levels and lipid peroxidation in maple syrup urine disease patients

Objective

In the present study we correlated the amino acids, branched-chain α-keto acids and α-hydroxy acids levels with the thiobarbituric acid-reactive species (TBARS) measurement, a lipid peroxidation parameter, in plasma from treated MSUD patients in order to examine whether these accumulated metabolites could be associated to the oxidative stress present in MSUD.

Design and methods

TBARS, amino acids, branched-chain α-keto acids and α-hydroxy acids concentrations were measured in plasma samples from treated MSUD patients.

Results

We verified that plasma TBARS was increased, whereas tryptophan and methionine concentrations were significantly reduced. Furthermore TBARS measurement was inversely correlated to methionine and tryptophan levels.

Conclusions

Considering that methionine and tryptophan have antioxidant activities, the data suggest that the imbalance of these amino acids may be involved with lipid peroxidation in MSUD.     

Effects of polyenylphosphatidylcholine on cytokines,nitrite/nitrate levels,antioxidant activity and lipid peroxidation in rats with sepsis

OBJECTIVES: To determine the effect of pretreatment with polyenylphosphatidylcholine (lecithin, PPC) on plasma levels of tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-10, total nitrite/nitrate (NOx), and tissue levels of superoxide dismutase (SOD) and malondialdehyde (MDA) in septic rats. DESIGN: Prospective, randomized, controlled animal study. SETTING: University laboratory. SUBJECTS: Forty-five Spraque-Dawley rats were divided into three groups: group C, sham-operated; group S, sepsis; and group P, sepsis pretreated with PPC. INTERVENTIONS: Rats were made septic by cecal ligation and puncture (CLP). Group P rats were treated with PPC (100 mg/day orally) for 10 days before sepsis. Twenty-four hours later CLP, plasma concentrations of TNF-alpha, IL-6 and IL-10 and plasma levels of NOx were measured. SOD and MDA were determined in liver, lung and heart homogenates. MEASUREMENTS AND MAIN RESULTS: All rats in group P survived during the 24-h observation time after CLP, whereas survival rate in group S was 66.7% (10/15; P<0.05). PPC significantly reduced plasma levels of TNF-alpha (P=0.006), IL-6 (P=0.007), IL-10 (P=0.016), NOx (P<0.001), and tissue levels of MDA (P<0.001) in group P with respect to in group S. Tissue levels of SOD significantly increased in group P when compared with group S (P<0.001). CONCLUSIONS: These results show that PPC pretreatment exerts cumulative effects in decreasing the levels of cytokines, NOx, and tissue MDA concentrations, with a concomitant increase in survival in septic rats. Lecithin therapy may be a useful adjuvant therapy in controlling of the excessive production of the inflammatory cytokines in patients with severe sepsis. DESCRIPTOR: SIRS/sepsis, experimental studies.     

Lipid peroxidation biomarkers for evaluating oxidative stress and assessing antioxidant capacity in vivo

Recently, the biological roles of lipid peroxidation products have received a great deal of attention not only for elucidating pathological mechanisms but also for practical clinical applications as biomarkers. In the last 50 years, lipid peroxidation has been the subject of extensive studies from the viewpoints of mechanisms, dynamics, product analysis, involvement in diseases, inhibition, and biological signaling. Lipid hydroperoxides are formed as major primary products, but they are substrates for various enzymes and they also undergo various secondary reactions. During this decade, hydroxyoctadecadienoic acid from linoleates, F₂-isoprostanes from arachidonates, and neuroprostanes from docosahexanoates have been proposed as biomarkers for evaluating oxidative stress in vivo and its related diseases. The implications of lipid peroxidation products in vivo will be briefly reviewed and their practical applications will be discussed.     

Oxidant-antioxidant status in patients with oral squamous cell carcinomas at different intraoral sites

OBJECTIVES: To compare the extent of lipid peroxidation and the status of antioxidants in tumor and venous blood of patients with oral squamous cell carcinoma (OSCC) at different intraoral sites. DESIGN AND METHODS: Twenty four patients with OSCC at different intraoral sites and an equal number of age- and sex-matched reference subjects were chosen for the study. The concentrations of lipid peroxides and reduced glutathione (GSH) and the activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) were estimated in tissues and blood. RESULTS: Diminished lipid peroxidation in tumor tissue was accompanied by decreased activities of SOD and CAT with increase in GSH and GSH-dependent enzymes. In contrast, enhanced lipid peroxidation with decrease in antioxidants was observed in the venous blood of OSCC patients. CONCLUSION: No significant differences in lipid peroxidation and antioxidant levels were observed between patients with OSCC at different intraoral sites. However, our results revealed differences between the tumor and blood with respect to their susceptibility to lipid peroxidation and antioxidant status.     

Effect of vitamins C and E on antioxidant status of breast-cancer patients undergoing chemotherapy

What is known and Objective: Reactive oxygen/nitrogen species generated by antineoplastic agents are prime suspects for the toxic side‐effects of acute or chronic chemotherapy. The present study was undertaken to test whether vitamins C and E (VCE) supplementation protect against some of the harmful effects of commonly used anticancer drugs in breast‐cancer patients. Methods: In a randomized 5‐month study, the activity of various antioxidant enzymes (superoxide dismutase, catalase, glutathione‐S‐transferase and glutathione reductase) and the levels of malondialdehyde and reduced glutathione were measured in forty untreated breast‐cancer patients (stage II) and compared with those of healthy controls. The degree of DNA damage was also assessed in the peripheral lymphocytes of the patients by alkaline single cell gel electrophoresis. The untreated patients were then randomly assigned to either treatment with chemotherapy alone (5‐fluorouracil 500 mg/m² i.v. day 1, doxorubicin 50 mg/m² i.v. day 1 and cyclophosphamide 500 mg/m² i.v. day 1, every 3 weeks for six cycles) or to the same chemotherapy regimen supplemented with VCE (vitamin C 500 mg tablet and vitamin E 400 mg gelatin capsule). On completion of the treatments, both the groups were studied again for the levels of the markers measured prior to treatment. Results and Discussion: The untreated group showed significantly lower levels of antioxidant enzymes (P < 0·001) and reduced glutathione (P < 0·001), and more extensive lipid peroxidation (P < 0·001) and DNA damage than healthy controls. Similar but less pronounced patterns were observed in the patients receiving chemotherapy alone. The group of patients receiving VCE supplementation had all the marker levels moving towards normal values. Activities of superoxide dismutase, catalase, glutathione‐S‐transferase and glutathione reductase, and the levels of reduced glutathione were significantly increased (P < 0·01) while, the levels of malondialdehyde and DNA damage were significantly (P < 0·01) reduced in the VCE supplemented group relative to those of patients receiving chemotherapy alone as well as relative to the pretreatment levels. What is new and Conclusion: Co‐administration of VCE restored antioxidant status, lowered by the presence of breast‐cancer and chemotherapy. DNA damage was also reduced by VCE. The results suggest that VCE should be useful in protecting against chemotherapy‐related side‐effects and a randomized control trial to evaluate the effectiveness of VCE in breast‐cancer patients using clinical outcomes would be appropriate.     

Alpha lipoic acid posses dual antioxidant and lipid lowering properties in atherosclerotic-induced New Zealand White rabbit

There is accumulating data demonstrated hypercholesterolemia and oxidative stress play an important role in the development of atherosclerosis. In the present study, a protective activity of alpha-lipoic acid; a metabolic antioxidant in hypercholesterolemic-induced animals was investigated. Eighteen adult male New Zealand White (NZW) rabbit were segregated into three groups labelled as group K, AT and ALA (n = 6). While group K was fed with normal chow and acted as a control, the rest fed with 100 g/head/day with 1% high cholesterol diet to induce hypercholesterolemia. 4.2 mg/body weight of alpha lipoic acid was supplemented daily to the ALA group. Drinking water was given ad-libitum. The study was designed for 10 weeks. Blood sampling was taken from the ear lobe vein at the beginning of the study, week 5 and week 10 and plasma was prepared for lipid profile estimation and microsomal lipid peroxidation index indicated with malondialdehyde (MDA) formation. Animals were sacrificed at the end of the study and the aortas were excised for intimal lesion analysis. The results showed a significant reduction of lipid peroxidation index indicated with low MDA level (p < 0.05) in ALA group compared to that of the AT group. The blood total cholesterol (TCHOL) and low density lipoprotein (LDL) levels were found to be significantly low in ALA group compared to that of the AT group (p < 0.05). Histomorphometric intimal lesion analysis of the aorta showing less of atheromatous plaque formation in alpha lipoic acid supplemented group (p < 0.05) compared to that of AT group. These findings suggested that apart from its antioxidant activity, alpha lipoic acid may also posses a lipid lowering effect indicated with low plasma TCHOL and LDL levels and reduced the athero-lesion formation in rabbits fed a high cholesterol diet.     

Tissue lipid peroxidation and antioxidant status in patients with adenocarcinoma of the breast

BACKGROUND: The results obtained for serum cystatin C, which has been proposed as a novel marker of glomerular filtration rate (GFR), in kidney and liver transplant are still very limited. In our study, the relationship between serum cystatin C and creatinine in kidney and liver transplant patients was investigated. METHODS: Serum cystatin C and creatinine concentrations were determined in 182 samples from 52 kidney transplant patients and 71 samples from 28 liver transplant patients at 1-9870 days post-transplantation time. Eighty-seven serum samples from 66 patients with different types of chronic kidney disease were also analysed. RESULTS: The serum creatinine (r=-0.517, p<0.001) and cystatin C (r=-0.409, p<0.001) concentrations were negatively correlated with the post-transplantation time in the kidney transplant patients. In the liver transplant patients, the correlation between these variables is not statistically significant. The creatinine/cystatin C ratio in the liver transplant group is significantly lower than in the other group of patients (p<0.001). This ratio in the kidney transplant patients groups is significantly lower than in the kidney disease group (p<0.001). In the kidney transplant patients the creatinine/cystatin C ratio and the post-transplantation time were negatively correlated (r=-0.523, p<0.001); however, in the liver transplant patients the correlation between these variables was not significant. CONCLUSIONS: In the groups of kidney disease and kidney transplant patients, as renal function decreases, there is an increase in the creatinine/cystatin C ratio. This may be due to the fact that, since creatinine is eliminated by glomerular filtration and tubular secretion, as renal function is impaired, its serum concentration increases to a greater extent than that of cystatin C, which is only eliminated by glomerular filtration. In the liver transplant patients, the creatinine/cystatin C ratio is lower than in the other groups. This may be due to better preserved renal function, lower muscular mass and a reduced rate of creatine formation and creatinine production in some of these patients. The serum cystatin C would be a better GFR marker than the widely used creatinine in liver transplant patients.     

Lipid and protein oxidation and antioxidant status in patients with angiographically proven coronary artery disease

OBJECTIVES: We aimed to evaluate the association of lipid peroxidation, protein oxidation and antioxidant system, and to assess an association with the severity of the disease, in patients with and without coronary artery disease (CAD) documented by coronary angiography. DESIGN AND METHODS: The population included 208 patients, undergoing clinically indicated coronary angiography. While the subjects with normal coronary angiograms (n=54) were evaluated as controls, the patients with CAD (n=154) were divided into three categories according to the number of diseased coronaries; one-vessel (n=50), two-vessels (n=51) and three-vessels (n=53). Lipid parameters were determined by routine laboratory methods. Plasma malondialdehyde and vitamin E concentrations were determined with the high-performance liquid chromatography. Other oxidant and antioxidant parameters were studied spectrophotometrically. RESULTS: While plasma malondialdehyde levels, the susceptibilities of erythrocyte and apolipoprotein B containing lipoproteins to in vitro induced oxidative stress, serum protein carbonyls, low density lipoprotein-cholesterol, triglyceride, apolipoprotein B and lipoprotein (a) levels had significantly increased, high-density lipoprotein-cholesterol and apolipoprotein AI levels, erythrocyte glutathione peroxidase, glutathione reductase, glucose 6 phosphate dehydrogenase, serum catalase, paraoxonase and arylesterase activities, plasma vitamin E and C and carotenoid levels had significantly decreased. The odds ratios for one-, two-, and three-vessel disease increased across especially higher tertiles of concentrations for oxidation parameters and lower tertiles of concentrations for antioxidant parameters. CONCLUSIONS: According to the results, we suggest that increased lipid and protein oxidation products and decreased antioxidant enzymes and vitamins contribute to increased oxidative stress which in turn is related to the severity of the disease.     

次声作用对大鼠大脑皮层脂质过氧化的影响

目的：观察8Hz,130dB次声作用于大鼠不同时间后，大脑皮层脂质过氧化相关指标的变化，以探讨次声引起脑损伤的机理。方法：将35只Ⅱ级、雄性、SD大鼠随机分为对照组和次声作用7d,14d,21d,28d组五组，用8Hz,130dB次声作用，每天1次，每次2h，各组于最后一次作用结束后0．5－1h内取大脑皮层，制成10％的组织匀浆测定GSH－Px活性，MDA含量和SOD活性的变化。结果：与对照组相比，大鼠大脑皮层GSH－Px活性在7d组无显著性变化（P＞0．05），在14d组、21d组、28d组和显著性升高（P＜0．05）；MDA含量在7d组、14d组有显著怀升高（P＜0．05),21d组、28d组恢复至对照组水平（P＞0．05）；SOD活性有下降的趋势，但无显著性意义（P＞0．05）。结论：次声作用后，引发大鼠大脑皮层组织的脂质过氧化－抗氧化反应，造成脑组织的损伤。