Oxidized LDL metabolites with high family risk for premature cardiovascular disease

Objective: Considering the importance of primary prevention of Cardiovascular Disease (CVD) from childhood, especially in children with high family risk for premature atherosclerosis, and also the importance of oxidized LDL in the process of atherosclerosis, the main metabolites of ox-LDL i.e. Malondialdehyde (MDA) and Conjugated diene (CDE) have been measured in children of high risk families and compared with a control group.Methods: Children and adolescents (6–18 years) of parents with premature myocardial infarction (Ml ≤ 55y in men and ≤ 65y in women), were selected as the case group. The control group included neighbors of the case group matched for age and socioeconomic status. All samples have been selected by simple random sampling. Both the case and control groups were divided in two subgroups : those with a total cholesterol and/or LDL-C ≥95th centile and those with normal lipid levels. Each subgroup consisted of 32 subjects, so 128 subjects were studied (64 in the case and 64 in the control group). MDA and CDE were measured by spectrophotometry using molar absorbivity. Data were analyzed by SPSS_v10/Win software using ANOVA, Bon-ferroni, Scheffe-Duncan, Tukey-HSD, and the Student’s t-test.Result: The mean MDA value in the case and control groups was significantly different (1.84 ± 0.43 vs. 1.67 ± 0.41 Μmol/L, p=0.03), but this difference was not significant regarding the mean CDE level (0.50 ± 0.05 vs. 0.47 ± 0.04 Μmol/ L, p>0.05). The mean MDA level in the case group with hyperlipidemia was significantly higher than that in the case group without hyperlipidemia (1.985 ± 0.516 vs. 1.690 ± 0.366, Μmol/L, P=0.02) and also higher than control group with or without hyperiipidemia (1.985 ± 0.516 vs. 1.720 ± 0.389,1.615 ± 0.429 Μmol/L respectivety, P<0.05). The mean CDE level in the case group with hyperiipidemia was significantly higher than the case group without hyperlipidemia (0.542 ± 0.034 vs. 0.494 ± 0.049 Μmol/L, P=0.04) and higher than the control group with or without hyperiipidemia (0.542 ± 0.034 vs. 0.464 ± 0.051, 0.484 ±0.048 Μmol/L respectively, p<0.05). In case boys with hyperiipidemia, the mean MDA (2.03 ± 0.2 Μmol/L) and the mean of CDE (0.56 ± 0.04 Μmol/L) was significantly higher than other subgroups (P<0.05).Conclusion: Considering the increased susceptibility of LDL to oxidation in children with high family risk for premature CVD, special attention should be paid to consumption of foods and seasoning containing antioxidants from childhood especially in high risk families.     

鼻息肉组织和血清中SOD、MDA的测定及其意义

目的测定鼻息肉病人鼻息肉组织和血清中超氧化物歧化酶(superoxidedismutase,SOD)活性、丙二醛(malondialdehyde,MDA)含量的变化并探讨其意义。方法通过生物化学方法分别测定30例鼻息肉病人鼻息肉组织和血清中SOD的活性与MDA含量,以20例鼻中隔偏曲病人的下鼻甲黏膜和血清作为对照组。结果①实验组SOD活性显著低于对照组(P<0.01)。②实验组MDA含量显著高于对照组(P<0.01)。结论①鼻息肉病人清除自由基能力下降,脂质过氧化反应活跃。②提示自由基代谢紊乱为鼻息肉的发病机制之一。     

Protective effects of melatonin and vitamin E in brain damage due to gamma radiation

Gamma radiation is known to cause serious damage in the brain, and many agents have been used for neuroprotection. In this study, lipid peroxidation levels and histopathological changes in brain tissues of whole-body irradiated rats with likely radiation injury were compared to those with melatonin and vitamin E protection. Forty rats in four equal groups were used. The control group received neither radiation nor medication. The remaining groups received doses of 720 cGy in two equal fractions 12 h apart. The second group received radiation but no medication, the third received radiation plus 100 mg/kg per day of vitamin E i.p., and the fourth received radiation plus 100 mg/kg per day of melatonin i.p. over 5 days. On the 10th postoperative day, all the rats were decapitated and specimens from parietal cortices were analyzed for tissue malondialdehyde (MDA) levels and histopathological changes. Increases in MDA were relatively well prevented by melatonin treatment but less so with vitamin E therapy. On histopathological examination, melatonin significantly reduced the rates of edema, necrosis, and neuronal degeneration, whereas vitamin E reduced only necrosis. Neither substance was capable of preventing vasodilatation. In conclusion, melatonin may be useful in preventing the pathological changes of secondary brain damage as a result of free oxygen radicals generated by irradiation.     

Clinical importance of erythrocyte malondialdehyde levels as a marker for cognitive deterioration in patients with dementia of Alzheimer type: a repeated study in 5-year interval

OBJECTIVES: The aim of the present study was to determine the effects of aging and dementia of the Alzheimer type (DAT) on lipid peroxidation and antioxidant enzyme activities. DESIGN AND METHODS: Twenty-six patients with DAT were included in the present study. Group I: 26 patients diagnosed as DAT and studied 5 yr ago. Group II: This group consisted of the same patients as Group I at the present time. Activities of CuZn superoxide dismutase (CuZn SOD) and glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) concentrations of these 26 subjects were measured and mini mental state examination (MMSE), brief psychiatric rating scale (BPRS), Hamilton depression rating scale (HDRS) were applied. RESULTS: The results revealed that 26 dementia patients had worsened cognitive symptoms and significantly increased CuZn SOD and MDA levels and decreased GSH-Px levels after 5 yr. Significant correlation was found between age and CuZn SOD (r: +0.406, p: 0.034), and between MMSE and MDA (r: -0.411, p: 0.032). CONCLUSIONS: We can conclude that MDA, CuZn SOD, and GSH-Px were significantly affected in the patients with Alzheimer disease. The most striking finding of this study is the significant correlation between MMSE and MDA in patients with DAT.     

Malondialdehyde and Nitric Oxide Levels in the Plasma of Patients with Advanced Laryngeal Cancer

Purpose. We investigated alterations in plasma nitrite, nitrate, total nitric oxide (NO), and malondialdehyde (MDA) levels in patients with advanced stage laryngeal cancer.Methods. We measured the levels of MDA and total NO^–₂, as well as the NO^–₃ marker for NO generation, in 25 patients with advanced laryngeal cancer and 15 healthy control subjects.Results. The levels of plasma MDA, NO, and NO^–₃ were significantly higher in the patients with laryngeal cancer than in the healthy controls (P 0.001 for all). On the other hand, although plasma NO^–₂ was increased in the patient group, the statistical difference was not significant (P 0.05). Moreover, the MDA and NO levels did not differ significantly between patients with stage III and stage IV laryngeal cancer.Conclusion. These findings demonstrate that oxidative stress is increased in patients with advanced laryngeal cancer.     

Effect of acute and prolonged sprint training and a detraining period on lipid peroxidation and antioxidant response in rats

The purpose of this study was to determine the effect of sprint exercise and a detraining period on lipid peroxidation (malondialdehyde, MDA) and response of antioxidant system (ferric reducing ability of plasma (FRAP), uric acid, bilirubin and total protein). Forty-two male rats were divided randomly into two groups: sprint group (experimental) (n=24) and control group (n=18, without any training programme). The experimental group trained for 12 weeks, 3 times per week, with given intensities. Five trained rats experienced the detraining, so the effects of detraining were also studied (from the 8th to 12th weeks). Data were analysed using a two-way repeated ANOVA. A significant difference between the two groups was observed for MDA (p=0.022), FRAP (p=0.005) and bilirubin (p=0.002) but for total protein and uric acid no significant change occurred. In the experimental group, a significant difference was found through various assessments for MDA (p=0.001), FRAP (p=0.001), bilirubin (p=0.008) and uric acid (p=0.012). It can be concluded that this protocol of sprint exercise training causes adaptation in the antioxidant system and lipid peroxidation, but by detraining these results will be reversed.     

针刺防治实验性动脉再狭窄模型大鼠抗氧自由基作用的初步研究

目的：探讨针刺治疗动脉再狭窄的作用机理。方法：用空气干燥法诱发大鼠颈总动脉再狭窄模型。以复方丹参注射液作对照。观察针刺对动脉再狭窄模型大鼠颈总动脉去内皮损伤的内膜增生及氧自由基的影响。结果：针刺能抑制动脉去内皮损伤的内膜增生。升高模型大鼠血清中超氧化物歧化酶（SOD）的活性。降低丙二醛（MDA）的含量。结论：针刺具有抗氧自由基的能力。逆转动脉再狭窄的病理进程，对动脉再狭窄具有较好的防治作用。     

映山红总黄酮抗炎作用的实验研究

目的研究映山红总黄酮(TFR)的抗炎作用及其可能的机制。方法通过二甲苯致小鼠耳肿胀和蛋清致大鼠足爪肿胀模型观察TFR的抗炎作用,并测定大鼠血清和足爪组织中一氧化氮(NO)、丙二醛(MDA)、前列腺素E2(PGE2)的含量和一氧化氮合酶(NOS)活性。结果50、100 mg/kg的TFR能明显抑制二甲苯致小鼠耳片肿胀;25、50、100 mg/kg的TFR可显著抑制蛋清致大鼠足爪的肿胀;在蛋清诱导大鼠足爪肿胀模型中,TFR使血清和脚爪组织屮MDA含量减少,同时脚爪组织中NOS活性、NO和PGE2含量也有显著的下降。结论TFR有一定的抗炎作用,其作用可能与抑制PGE2和NO合成及抗脂质过氧化有关。     

A prospective study of early-pregnancy plasma malondialdehyde concentration and risk of preeclampsia

OBJECTIVES: Preeclampsia is associated with elevated plasma malondialdehyde concentration, but prospective data are scarce. We examined the relation between early-pregnancy plasma malondialdehyde and subsequent preeclampsia risk. DESIGN AND METHODS: In a nested case-control analysis, we measured malondialdehyde concentrations in 22 women who developed preeclampsia and 711 who remained normotensive during pregnancy. We calculated adjusted odds ratios (OR) and 95% confidence intervals (CI). We repeated analyses after adjustment for early-pregnancy plasma lipid concentrations, which are related to preeclampsia risk and lipid peroxidation measures. RESULTS: After adjustment for confounders, preeclampsia risk increased across tertiles of malondialdehyde concentration (trend P = 0.04). Further adjustment for triglyceride concentration slightly strengthened the association. Middle- and high-tertile malondialdehyde ORs were 3.2 (CI 0.8-12.2) and 4.2 (1.1-16.0) versus low-tertile exposure. CONCLUSIONS: Early-pregnancy plasma malondialdehyde concentration is positively associated with subsequent preeclampsia risk independent of plasma lipid concentrations. These results support lipid peroxidation as an etiologic component of preeclampsia.