高浓度花生四烯酸诱导小鼠成纤维细胞L929凋亡的研究

目的：探讨花生四烯酸是否能诱导小鼠成纤维细胞L929凋亡及其可能机制。方法：噻唑蓝（MTT）法检测细胞存活率,比色法测定乳酸脱氢酶（LDH）释放率,硫代巴比妥酸法测定细胞脂质过氧化产物丙二醛（MDA）含量,Hoechst 33258染色观察凋亡细胞核形态变化,DNA琼脂糖凝胶电泳检测DNA降解。结果：L929细胞在40-160 μmol/L花生四烯酸作用24 h后,细胞存活率明显下降,LDH释放率和细胞MDA含量显著增加（P<0.01）。经160 μmol/L花生四烯酸处理后的L929细胞呈现典型的凋亡核固缩表现。琼脂糖凝胶电泳显示DNA凋亡梯带。结论：高浓度花生四烯酸（80-160 μmol/L）能诱导小鼠成纤维细胞L929凋亡,可能与其促脂质过氧化作用有关。     

Absence of lipid peroxidation as determined by ethane exhalation in rats treated with 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD)

The exhalation of ethane is widely used as an indicator of in vivo lipid peroxidation. To test the hypothesis that lipid peroxidative events are involved in the toxicity of 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD), we administered a lethal dose of TCDD (60 g/kg), IP to male Sprague Dawley rats (160–180 g) and measured by gas chromatography the exhalation of ethane into the atmosphere of a closed all-glass exposure chamber. TCDD-treated rats exhaled only slightly more ethane than control rats at a single time point 7 days following TCDD administration. Since the exhalation of ethane is the net result of the endogenous production of the gas and its metabolic degradation, the latter was quantified by measuring the clearance of exogenous ethane (initial concentration = 100 ppm) introduced to the atmosphere of the exposure chamber. The clearance of ethane in TCDD-treated rats was markedly decreased, reaching a minimum 7 days following TCDD treatment. Apparently, the slight increase in exhaled ethane was due to an inhibition of ethane metabolism caused by TCDD. However, rats obviously intoxicated and having lost considerable body weight might be impaired in their ability to transport ethane. To bypass this problem we injected ethane (0.2 ml) directly into the rats IP. Here also the metabolic clearance in TCDD-treated rats was diminished. In a further experiment, rats treated with dithiocarb at a dose where ethane metabolism was totally inhibited exhaled more ethane than did TCDD-treated rats. It is therefore concluded that the slight increase in ethane exhalation following a lethal dose of TCDD is due to a partial inhibition of ethane metabolism and that there is no net increase in ethane production due to lipid peroxidation. Indeed when TCDD-treated rats were administered Fe⁺⁺, a well-known initiator of lipid peroxidation, they were less competent to carry out lipid peroxidation than rats treated with Fe⁺⁺ alone.A preliminary report of this study was presented at the 68th annual meeting of the Federation of American Societies for experimental Biology, St. Louis, MO, USA, April, 1984This work is part of the M.D. thesis of U. Regel     

Effects of cadmium treatment on selenium-dependent and selenium independent glutathione peroxidase activities and lipid peroxidation in the kidney and liver of rats maintained on various levels of dietary selenium

Rats fed a basal, low-selenium diet, or this diet supplemented with 0.1 ppm and 1.0 ppm selenium and treated with cadmium, showed significant reductions in the activity of the selenoenzyme glutathione peroxidase in kidney and liver. Cadmium treatment resulted in a significant increase in the activity of selenium-independent glutathione peroxidase activity in the liver of selenium-supplemented rats. Selenium-independent glutathion peroxidase activity was significantly reduced in the kidney of rats fed the basal low-selenium diet. There was no significant increase in lipid peroxidation in any of the groups studied. Cadmium concentrations in the kidney and liver of these animals ranged from about 250 to 700 g Cd/g tissue, dry weight.Supported by NIEHS Center Grant ES-00159 and a Grant from the Selenium-Tellurium Development Association     

Mitoxantrone: Propensity for free radical formation and lipid peroxidation — implications for cardiotoxicity

Summary Results of comparative studies on stimulation of the rates of cofactor consumption, superoxide generation and hydrogen peroxide production by mitoxantrone (Novantrone®; dihydroxyanthracenedione; MXN), ametantrone (AM), doxorubicin (DOX) and daunorubicin (DNR) in the presence of NADPH-cytochrome P-450 reductase, NADH dehydrogenase, or rabbit hepatic microsomes have been reported. MXN and AM were substantially less effective in stimulating the rate of cofactor oxidation, superoxide formation or hydrogen peroxide production relative to the anthracyclines. In the presence of P-450 reductase, the rate of NADPH oxidation or superoxide generation produced by 100 M MXN or AM was only 15% and 2% respectively of that produced by 100 M anthracycline.The effects of MXN and AM on lipid peroxidation in hepatic microsomes, cardiac sarcosomes and cardiac mitochondria were determined and compared with those produced by ADM. MXN and AM at 50 M inhibited the basal rate of NADPH-dependent rabbit liver microsomal lipid peroxidation by 50%; in contrast, DOX enhanced the rate of hepatic microsomal lipid peroxidation by 2-and 2.5-fold at 100 and 200 M, respectively. Rabbit cardiac sarcosomal NADPH-dependent lipid peroxidation was inhibited completely at 100 M anthracenedione. NADH-dependent lipid peroxidation in cardiac mitochondria was diminished by 50 M MXN and AM, whereas 50 M DOX produced a 2-fold stimulation in lipid peroxidation. The anthracenediones also effectively inhibited DOX-stimulated lipid peroxidation with 50% inhibition occurring at 4 M (MXN) and 6 M (AM). Moreover, both MXN and AM potently inhibited iron (100 M)-stimulated lipid peroxidation in rabbit hepatic microsomes with 80% inhibition produced by 15 M anthracenedione.These results are consistent with the diminished cardiotoxicity of mitoxantrone and ametantrone relative to DOX or DNR and may require a reassessment of the role of lipid peroxidation in the mechanism(s) of quinone antineoplastic agent-mediated cardiotoxicity.     

Are the metabolic characteristics of congenital intraspinal lipoma cells identical to,or different from normal adipocytes?

Congenital intraspinal lipomas are frequently responsible for progressive neurological deficits caused by distortion or compression of the nervous system. Since fat metabolism in these lesions has not been previously studied, the aim of this study was to determine whether intraspinal lipoma cells behave like lipomas or like normal adipocytes. In 11 patients, intraspinal lipoma cells were compared with normal adipocytes isolated from adjacent subcutaneous adipose tissue for the following parameters: lipoprotein lipase (LPL), lipogenesis from U¹⁴C glucose, ß-receptor number, adenylate cyclase activity, cyclic AMP production, and lipolysis in response to ß- and ₂-adrenergic agonists. No significant difference between these two cell populations was found, suggesting that intraspinal lipomas are not lipomatous tumors, but hamartomatous lesions capable of growth and regression along with the changes in the rest of the fatty pool. This emphasizes the danger of an abnormal weight gain, as well as the possible usefulness of an hypocaloric diet in patients who worsen in spite of previous surgery.Research supported by INSERM (CRL 824005 and CRE 854010) and the D.G.R.     

Nutritional Importance of Selected Fresh Fishes,Shrimps and Mollusks to Meet Compliance with Nutritional Guidelines of n-3 LC-PUFA Intake in Spain

Fishery products are the main source of dietary n-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA). Following the European Commission’s request to address the risks and benefits of seafood consumption, and taking into account the great variability of nutrient and contaminant levels in fishery products, the present work aims to estimate the n-3 LC-PUFA provided per serving of selected fishes, shrimps and mollusks that are commonly consumed in Spain. This would enable the establishment of a risk–benefit analysis of fish consumption and provide recommendations for fish intake to comply with nutritional guidelines of n-3 LC-PUFA intake. We confirmed high variation in the pattern and contents of fatty acids for different species. n-6 PUFA were minor fatty acids, whereas palmitic (C16:0), oleic (C18:1 n-9), and mainly eicosapentaenoic (C20:5 n-3) and docosahexaenoic (C22:6 n-3) acids were the major fatty acids in the sample. Therefore, consumption of 2–3 servings per week of a variety of fishery products may contribute to compliance with the recommended daily n-3 LC-PUFA intake while maintaining an adequate balance to avoid contaminant-derived potential risks (metals and others). Taking the fatty acid content of fishery products described in this study into consideration, it is advisable to include one serving of fatty fish per week in order to meet recommended n-3 LC-PUFA levels.     

Dietary Factors and Prostate Cancer Development,Progression, and Reduction

Due to the constantly increasing number of cases, prostate cancer has become one of the most important health problems of modern societies. This review presents the current knowledge regarding the role of nutrients and foodstuff consumption in the etiology and development of prostate malignancies, including the potential mechanisms of action. The results of several in vivo and in vitro laboratory experiments as well as those reported by the clinical and epidemiological research studies carried out around the world were analyzed. The outcomes of these studies clearly show the influence of both nutrients and food products on the etiology and prevention of prostate cancer. Consumption of certain nutrients (saturated and trans fatty acids) and food products (e.g., processed meat products) leads to the disruption of prostate hormonal regulation, induction of oxidative stress and inflammation, and alteration of growth factor signaling and lipid metabolism, which all contribute to prostate carcinogenesis. On the other hand, a high consumption of vegetables, fruits, fish, and whole grain products exerts protective and/or therapeutic effects. Special bioactive functions are assigned to compounds such as flavonoids, stilbenes, and lycopene. Since the influence of nutrients and dietary pattern is a modifiable risk factor in the development and prevention of prostate cancer, awareness of the beneficial and harmful effects of individual food ingredients is of great importance in the global strategy against prostate cancer.     

Directions of Changes in the Health Values of Dairy Products in the Opinion of Consumers

The aim of our research was to assess whether and to what extent the perceived change in the content of selected ingredients in dairy products is important for Polish consumers in accepting the enhancement of the health benefits of dairy products, including yogurt. The data were collected using a CAPI (Computer Assisted Personal Interview) survey on a sample of 983 consumers. The logistic regression model was used to predict the behavior of consumers associated with their willingness to accept the health aspects of improving dairy products. The results indicated that changes in the level of selected ingredients enhanced the willingness to accept increasing the health value of the product. The socio-demographic characteristics of the participants were not associated with the degree of their willingness to accept the improvement of the perceived health attributes. Practitioners in the dairy industry and policy makers can benefit from these results. When designing food products, it is worth focusing on increasing the nutritional value and enhancing the health value of food that is perceived by consumers as generally possessing positive health benefits, rather than on food that is perceived by them as possessing negative qualities.     

硒补充剂对妊娠期糖尿病患者血糖和血脂代谢及妊娠结局的影响分析

目的探讨硒补充剂对妊娠期糖尿病患者血糖、血脂代谢和妊娠结局的影响。方法将2018年7月-2019年6月盘锦市中心医院收治的45例妊娠期糖尿病患者随机分为对照组21例和硒酵母组24例。两组患者均给予健康教育、饮食指导、运动指导等常规治疗,硒酵母组在常规治疗基础上给予硒酵母片治疗。比较两组治疗前后空腹血糖、胰岛素抵抗指数、总胆固醇、甘油三酯、低密度脂蛋白胆固醇、高密度脂蛋白胆固醇水平及妊娠结局。结果治疗后两组空腹血糖和胰岛素抵抗指数均较治疗前下降,且硒酵母组两项指标均低于对照组,差异均具有统计学意义(P<0.05)。治疗后两组孕妇总胆固醇、甘油三酯、低密度脂蛋白胆固醇水平较治疗前下降,且硒酵母组三项指标水平低于对照组,差异均具有统计学意义(P<0.05)。治疗后硒酵母组高密度脂蛋白胆固醇水平高于治疗前,差异具有统计学意义(P<0.05)。对照组治疗前后以及两组治疗后高密度脂蛋白胆固醇水平差异均无统计学意义(P>0.05)。硒酵母组新生儿高胆红素血症发生率和新生儿住院率均低于对照组,差异均具有统计学意义(P<0.05)。两组其他不良妊娠结局差异均无统计学意义(P>0.05)。结论硒补充剂能够进一步改善妊娠期糖尿病患者的血糖和血脂代谢,同时,也能降低新生儿高胆红素血症发生率和住院率,值得推广使用。