极低频高压脉冲电场对萌发绿豆干旱伤害的缓解作用

采用峰值场强为100 kV·m^-1、脉宽80 ms、脉冲频率为1 Hz的极低频高压脉冲电场（ELF-PEF）处理-0.1 MPa的PEG-6000溶液中萌发的绿豆种子，研究了绿豆在萌发过程中鲜重、自发发光、延迟发光、丙二醛（MDA）含量和超氧化物歧化酶（SOD）活性的变化。结果表明，ELF-PEF对PEG胁迫下萌发的绿豆鲜重、自发发光和延迟发光积分强度促进作用分别达到了28.58%、78.35%和40.6%，说明ELF-PEF可以有效促进绿豆种子萌发过程中的生理代谢，缓解干旱胁迫对细胞的伤害作用。ELF-PEF通过提高PEG胁迫下萌发绿豆中SOD活性，降低MDA含量，缓解干旱胁迫对萌发绿豆的氧化损伤，ELF-PEF对细胞毛细吸水和代谢吸水的促进可能是其缓解干旱伤害的原因。     

Decrease in Antioxidant Status of Plasma and Erythrocytes from Geriatric Population

Background: Ageing is associated with an accumulation of free radical damage, which leads to physiological and clinical modifications. The study aims to find out the status of lipid profile, antioxidant enzymes, malondialdehyde in geriatric population. Patients/methods: The study was conducted on 150 subjects (75 healthy control between the ages of 20–30 years and 75 elderly subjects between ages of 50–70 years as cases). The following parameters were analyzed using the standard reference methods: lipid profile, reduced glutathione, glutathione peroxidase, glutathione reductase, catalase, superoxide dismutase and malondialdehyde. Results: The present study was conducted to estimate the oxidative stress parameters in geriatric population. Highly significant increase in total cholesterol (TC), triglyceride (TG), LDL-cholesterol (LDL-C), VLDL-cholesterol (VLDL-C), malondialdehyde, catalase and decrease in high density lipoprotein cholesterol (HDL-C), reduced glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase was observed in geriatrics when compared with their younger counterparts. Conclusion: This study concluded that there is enhanced oxidative stress and decreased antioxidant defence in geriatrics as compared to younger subjects which could play an important role in ageing. Dyslipidemia has become one of the important risk factors for the increasing prevalence of cardiovascular diseases. There is lack of awareness on the relationship between blood lipids and the risk of cardiovascular diseases in geriatric population. The strategy of early prevention should be adopted against dyslipidemia.     

Correlations between Oxidative DNA Damage, Oxidative Stress and Coenzyme Q10 in Patients with Coronary Artery Disease

The correlation of coronary artery disease (CAD) with pro-oxidant/antioxidant balance and oxidative DNA damage was investigated.Seventy-seven patients with CAD and 44 healthy individuals as control were included in this study. The comparative ratios of ubiquinol-10/ubiquinone-10, 8-hydroxy-2^''-deoxyguanosine/deoxyguanosine and the level of MDA measured by HPLC and the activities of GPX and SOD by colorimetric approach in blood samples obtained from patients with CAD were unraveled.8-OHdG/dG ratios, serum MDA level and GPX activity were found significantly elevated level in serum of CAD patients compared to control group. The SOD activity was observed in stable levels in CAD patients. Ubiquinol-10/ubiquinone-10 ratio was significantly lower in patients with CAD than the controls.The positive correlation was observed between 8-OHdG/dG ratios in both MDA levels and GPX activity, while the significant negative correlation was seemed between the ratio of 8-OHdG/dG and ubiquinol-10/ ubiquinone-10 as well as MDA levels and ubiquinol-10/ ubiquinone-10 ratio.We conclude that, both the disruption of pro-oxidant/antioxidant balance and oxidative stress in DNA may play an important role in the pathogenesis of coronary artery disease.     

Orexin A decreases lipid peroxidation and apoptosis in a novel hypothalamic cell model

Current data support the idea that hypothalamic neuropeptide orexin A (OxA; hypocretin 1) mediates resistance to high fat diet-induced obesity. We previously demonstrated that OxA elevates spontaneous physical activity (SPA), that rodents with high SPA have higher endogenous orexin sensitivity, and that OxA-induced SPA contributes to obesity resistance in rodents. Recent reports show that OxA can confer neuroprotection against ischemic damage, and may decrease lipid peroxidation. This is noteworthy as independent lines of evidence indicate that diets high in saturated fats can decrease SPA, increase hypothalamic apoptosis, and lead to obesity. Together data suggest OxA may protect against obesity both by inducing SPA and by modulation of anti-apoptotic mechanisms. While OxA effects on SPA are well characterized, little is known about the short- and long-term effects of hypothalamic OxA signaling on intracellular neuronal metabolic status, or the physiological relevance of such signaling to SPA. To address this issue, we evaluated the neuroprotective effects of OxA in a novel immortalized primary embryonic rat hypothalamic cell line. We demonstrate for the first time that OxA increases cell viability during hydrogen peroxide challenge, decreases hydrogen peroxide-induced lipid peroxidative stress, and decreases caspase 3/7 induced apoptosis in an in vitro hypothalamic model. Our data support the hypothesis that OxA may promote obesity resistance both by increasing SPA, and by influencing survival of OxA-responsive hypothalamic neurons. Further identification of the individual mediators of the anti-apoptotic and peroxidative effects of OxA on target neurons could lead to therapies designed to maintain elevated SPA and increase obesity resistance.     

Protective role of melatonin given either before ischemia or prior to reperfusion on intestinal ischemia-reperfusion damage

Tissue injury resulting from ischemia-reperfusion is of fundamental importance. Experimental evidence suggests that the generation of reactive oxygen species is significantly responsible for this type of injury. In the present study, besides investigating the protective role of melatonin on tissue damage caused by intestinal ischemia-reperfusion, the protective activity of this compound was also analyzed in both pre- and post ischemia melatonin-treated rats. The activities of the main antioxidative enzymes, catalase, superoxide dismutase and glutathione peroxidase in the intestine showed significant (P < 0.05) increases in melatonin-treated animals that were subjected to ischemia/reperfusion compared with those subjected only to ischemia/reperfusion. Also, results clearly indicate that the level of malondialdeyhde, an index of lipid peroxidation, decreased significantly (P < 0.05) when rats subjected to intestinal/reperfusion were given melatonin either before ischemia or before reperfusion.     

急性脑出血病人血清sICAM-1、MDA变化的临床研究

目的探讨急性脑出血病人血清可溶性细胞间黏附分子(sICAM-1)和丙二醛(MDA)含量变化及临床意义.方法采用双抗体夹心酶联免疫吸附(ELISA)法、硫代巴比妥酸(TBA)法分别测定80例急性脑出血病人和20例健康人血清中sICAM-1、MDA的含量.结果与正常对照组相比,急性脑出血病人血清sICAM-1、MDA含量明显升高(P＜0.01),sICAM-1、MDA在轻、中、重型组之间比较有统计学意义(P＜0.05,P＜0.01);72 h内不同发病时间各组sICAM-1、MDA均有统计学意义(P＜0.01);以25 h～48 h组为最高;急性脑出血病人血清sICAM-1、MDA两指标之间呈高度的正相关.结论急性脑出血白细胞黏附、机体氧化应激增强,病人血清sICAM-1、MDA明显升高,二者关系密切,参与了脑出血后脑损伤的病理过程;急性脑出血sICAM-1、MDA水平的高峰期在25 h～48 h;且随着神经功能缺损的严重程度、病灶体积增加而增高,可作为判定病情严重程度的参考指标.     

The effects of antioxidants on exercise-induced lipid peroxidation in patients with COPD

OBJEctive: The oxidant-antioxidant balance plays an important role in the pathogenesis of COPD. The aim of the present study was to evaluate the effects of exercise, as an oxidative stress factor on the oxidant-antioxidant balance and to investigate whether short-term antioxidant treatment affects lipid peroxidation products. METHODOLOGY: Twenty-one stable COPD patients and 10 control subjects were included in the study. Symptom-limited exercise tests were performed by all subjects. Blood was collected before and 1 h after exercise in control subjects and before, 1 and 3 h after exercise in COPD patients, for analysis of malondialdehyde (MDA), reduced glutathione (GSH) and vitamin E (VE) levels. VE and vitamin C treatments were added to the regular bronchodilator therapy in 10 COPD patients for 1 month. After the treatment period, an exercise test was performed and blood was collected again for MDA, GSH and VE levels. RESULTS: Baseline GSH and VE levels were significantly lower in the COPD group when compared with the control subjects. There was no statistically significant difference in MDA levels between the two groups. In the COPD group, MDA levels 3 h after exercise were significantly higher than at baseline. In contrast there were no significant differences in MDA, VE and GSH levels in the control group after exercise. VE and MDA levels increased significantly after exercise in COPD patients but there was no difference in GSH levels. Baseline exercise time was significantly lower in the COPD group than in the controls. In 10 COPD patients who were given antioxidant therapy, their exercise time increased significantly and there was no increase in MDA and VE levels after the repeated exercise test. CONCLUSIONS: Antioxidant levels were significantly lower in COPD patients than in control subjects. In these patients, exercise results in more significant oxidative stress and lipid peroxidation than in control subjects and antioxidant therapy may decrease lipid peroxidation following exercise and improve exercise capacity.     

沙棘总黄酮防紫外线损伤的实验研究

目的：通过中波紫外线（UVB）辐射皮肤损伤模型来探讨沙棘总黄酮对皮肤的保护修复作用,为寻找新型抗紫外线的药物提供实验依据。方法通过 UVB 反复照射,构建 UVB 辐射小鼠皮肤损伤模型,观察各组实验动物皮肤形态学变化、皮肤中超氧化物歧化酶（SOD）活性、皮肤内脂类受过氧化损伤的程度即丙二醛（MDA）的量和胶原蛋白量的变化程度。结果模型组较正常组皮肤形态学变化明显,表皮层增加,真皮层增厚,UVB 辐射皮肤损伤模型构建成功;模型组较正常组 SOD 活性和 MDA的量分别是极显著降低和升高（P＜0．01）,而阳性对照组和沙棘总黄酮给药组较模型组 SOD 的活性和 MDA 的量分别是极显著升高和降低（P＜0．01）;模型组较正常组胶原蛋白量显著降低（P＜0．05）,阳性对照组和沙棘总黄酮给药组胶原蛋白量较高（P＜0．01）,但阳性对照组出现了增生性瘢痕。结论沙棘总黄酮能有效防止 UVB 反复照射对皮肤造成的损伤,提高皮肤组织中SOD 活性和胶原蛋白量,抑制 MDA 的量升高和瘢痕增生,并对 UVB 导致小鼠皮肤光老化有拮抗作用。