The effect of two different doses comprising the simultaneous administration of intravenous B-complex vitamins and oral folic acid on serum homocysteine levels in hemodialysis patients

Background: Several regimens using different doses of folic acid (FA) alone or supplemented with B-complex vitamins (BCVs) have been tested for their ability to reduce total homocysteine (tHcy) serum levels in hemodialysis (HD) patients. In the present study, we assessed the effect of two different doses comprising the simultaneous administration of intravenous (IV) BCVs and an oral FA supplementation on serum tHCy levels in HD patients. Patients–methods: In a cohort of 49 patients (31 male, 18 female) undergoing chronic HD treatment for a mean of 40.0±40.7 months, serum concentrations of tHcy, folate and vitamin-B12 (vB12) were determined at the end of three sequential periods as follows: 20 weeks without any BCV and/or FA supplementation (period A), 20 weeks with a dose comprising the simultaneous administration of IV BCVs and an oral supplementation of 5 mg of FA once a week (period B), and 20 weeks with a dose comprising the simultaneous administration of IV BCVs and an oral supplementation of 5 mg of FA thrice a week (period C). An IV dose of BCVs consisting of a 5 mL solution containing vitamin B₁ (250 mg), vitamin B₆ (250 mg) and vitamin B₁₂ (1.5 mg) was administered at the end of hemodialysis. Results: Mean serum tHcy levels were significantly higher at the end of period A relative to levels at the end of periods B and C (35.8±23 μmol/L vs. 22.0±17.6 and 15.0±4.5 μmol/L, respectively; p < 0.000001). Mean serum folate levels and mean serum vB12 levels were significantly lower at the end of period A relative to levels at the end of periods B and C (p < 0.000001). Mean serum tHcy levels were lowest at the end of period C (p < 0.000001 in comparison to periods A and B), and 26 of the 49 HD patients (67.3%) possessed tHcy levels below 16 μmol/L. Conclusions: In HD patients, high doses consisting of the simultaneous administration of IV BCVs and an oral FA supplementation resulted in the efficient reduction of serum tHcy levels.     

Therapeutic effect of tamoxifen and energy-modulating vitamins on carbohydrate-metabolizing enzymes in breast cancer

Background Cancer cells have an abnormal energetic metabolism. One of the earliest discovered hallmarks of cancer had its roots in bioenergetics, as many tumours were found in the 1920s to exhibit a high glycolytic phenotype. An animal with cancer shows significant and progressive energy loss from the host (i.e. noncancerous) tissues, which could occur by the establishment of a systemic energy-depriving cycle involving the interaction of tumour glycolysis and host gluconeogenesis. Tamoxifen (TAM) is a nonsteroidal antioestrogen that is widely used in adjuvant therapy for all stages of breast carcinoma. To improve the therapeutic efficacy of TAM and to expand its usage in the treatment of breast cancer, it is necessary to establish an energy-enhancing programme. In order to provide sufficient energy and to prevent cancer cachexia, TAM can be supplemented with energy-modulating vitamins (EMV). In this investigation the augmentation of the efficacy of TAM by the effects of EMV supplementation on carbohydrate-metabolizing enzymes, the mitochondrial Krebs cycle and respiratory enzymes was evaluated in the mammary gland of carcinoma-bearing rats.Methods Female albino Sprague-Dawley rats were selected for the investigation. The experimental set-up included one control and four experimental groups. Mammary carcinoma was induced with 7,12- dimethyl benz(a)anthracene (25 mg), and TAM was administered orally (10 mg/kg body weight per day) along with EMV which comprised riboflavin (45 mg/kg per day), niacin (100 mg/kg per day) and coenzyme Q₁₀ (40 mg/kg per day).Results Measurements were made on tumour tissue and surrounding normal tissue in all experimental groups. Tumour tissue showed significant (P<0.05) increases in the glycolytic enzymes hexokinase, phosphoglucoisomerase and aldolase, and significant decreases in the gluconeogenic enzymes glucose-6-phosphatase and fructose-1,6-biphosphatase. In contrast, the surrounding tissue showed significant decreases in glycolytic enzymes and significant increases in gluconeogenic enzymes. The activities of the mitochondrial Krebs cycle enzymes isocitrate dehydrogenase, -ketoglutarate dehydrogenase, succinate dehydrogenase and malate dehydrogenase, and respiratory chain enzymes NADH dehydrogenase and cytochrome c oxidase were significantly reduced in both tumour and surrounding tissue of the mammary carcinoma-bearing rats. These biochemical disturbances were effectively counteracted by supplementation with EMV, which restored the activities of all these enzyme to their respective control levels.Conclusion Combination therapy of TAM with EMV not only alters carbohydrate metabolism but can also prevent body weight loss by enhancing the host energy metabolism.     

Application of a geographic information system to explore associations between air pollution and micronucleus frequencies in African American children and adults

Exposure to air pollution has been associated with adverse respiratory and cardiovascular health outcomes in both children and adults. In this study, we used geographic information systems (GISs) to explore possible associations between chromosomal damage in 65 African American children and their mothers from Oakland, California, and both proximity to traffic and regional ozone levels. Study participants were interviewed at the Healthy Child Clinic of Children's Hospital, Oakland, and their blood and buccal cells were collected for assessment of chromosomal damage by the micronucleus (MN) assay. Regional ozone levels, which decreased from April to November with a secondary peak in late summer, were highly correlated with season by month (r=-0.84, P=0.02) and strongly associated with MN frequency (frequency ratio (FR): 3.37, 95% confidence interval (CI): 1.30-8.72) in both cell types of children and adults. Additionally, MN frequencies were modestly associated with individual measures of traffic density in children (FR=2.45, 95% CI=0.86-7.10), but not in adults; this suggests a greater vulnerability to traffic-related air pollution in children. Smoking in the household also increased MN frequency in the lymphocytes of children (FR: 1.13, 95%CI: 1.01-1.24) and adults (FR: 1.06, 95%CI: 0.99-1.13), whereas vitamin use in adults decreased MN frequency in both lymphocytes and buccal cells (FR: 0.17, 95%CI: 0.02-1.31; FR: 0.18, 95%CI: 0.03-1.18, respectively). Our data indicate that GIS-generated measures of traffic density for individual households augment regional ozone monitoring data used to assess effects of air pollution. This approach helped to demonstrate elevated cytogenetic damage in exposed minority children.     

Anti-oxidant therapy for the treatment of coronary artery disease

Coronary artery disease is the most common cause of death in developed countries. It may present in many different ways, but most frequently as a myocardial infarction, sudden death, angina or heart failure. Preventive measures in relation to coronary artery disease are particularly important because of its high incidence, high mortality and because most patients die outside hospital. Since the oxidation of low density lipoprotein cholesterol (LDL-C) is a critical early step in the process of atheroma formation, taking anti-oxidants to prevent LDL-C oxidation may prove a very effective means of reducing coronary artery disease mortality. However, the role of anti-oxidants in coronary artery disease prevention needs to be evaluated as part of an overall strategy that includes pharmacological and non-pharmacological measures, which are described in this review. In addition, a more structured and scientific approach to anti-oxidant therapy needs to be adopted. This requires that evidence for oxidative stress in a particular condition is obtained, the nature and severity determined and an appropriate anti-oxidant is administered, in an effective dose, which can be shown to correct the oxidative stress. When this is achieved, meaningful clinical trials should be possible, which will determine the place of anti-oxidant therapy for the specified condition.     

维生素对动脉粥样硬化危险因素损伤血管内皮的保护作用

目的:探讨4种维生素联合应用,对动脉粥样硬化危险因素损伤血管内皮是否具有保护作用。方法:24只雄性家兔被随机分成3组。对照组喂普通饲料,模型组在普通饲料中加入胆固醇、猪油和甲硫氨酸,维生素组饲料同模型组,每天再另外灌胃给予维生素E、C、B6和叶酸,连续8周。第8周末,取血检测相关指标。结果:与对照组相比,模型组血脂(除HDL-C以外)、同型半胱氨酸和内皮素水平均显著升高(t=2.412,P<0.05;t=3.802～5.830,P<0.01),血清一氧化氮虽有降低,但在两组间没有显著差异;HDL-C/LDL-C比值明显减少(t=6.622P<0.01)。与模型组比较,维生素组血清总胆固醇、LDL-C.同型半胱氨酸和血浆内皮素水平均显著降低(t=2.514～2.726,P<0.05),而血清一氧化氮显著升高,HDL-C/LDL-C比值也明显增加(t=4.128～5.076,P<0.01)。结论:维生素E、C、B6和叶酸联合运用,能够降低血中多种危险因子的水平,调节血中内皮素和一氧化氮的平衡,减少或阻断危险因素对内皮功能的损伤,对血管内皮有保护作用。     

维生素D对致敏后佝偻病大鼠免疫漂移影响的研究

【目的】 建立致敏佝偻病动物模型并检测补充维生素D(vitamin D,VD)前后25-(OH)D₃、IgE、IFN-γ及IL-4变化,为儿科临床佝偻病及过敏性疾病防治提供实验依据。 【方法】 选用SD大鼠,建立致敏佝偻病模型,随机分为补D 30万U组(7只)、补D 60万U组(7只)、对照组(6只),实验组采用一次性肌注补D方法,饲养20 d天后采用ELLISA方法及流式细胞仪检测大鼠过敏及免疫指标。 【结果】 补D组较对照组比较,30万U维生素D可使致敏佝偻病SD大鼠外周血过敏指标IgE降低(P＜0.01),而60万U维生素D则使IgE上升(P＜0.01);30万U组IFN-γ的UR值上升(P＜0.05),但仍较正常鼠低,IL-4的UR值有所下降(P＜0.05);60万U组IFN-γ的UR值不但没有上升,反而下降更加明显(P＜0.05), IL-4的UR值则上升明显(P＜0.05)。 【结论】 一次性肌注30万U维生素D可以改善过敏机体的免疫状态,而当剂量达60万U时则加重过敏机体Th1/Th2细胞失衡,进一步加重机体的过敏反应。     

Update on cosmeceuticals

As youth and perception of beauty are considered to be of great importance, an increasing number of new cosmeceuticals have been developed in recent years. This article will briefly present the problems of distinguishing cosmetics, cosmeceuticals or drugs and describe important new developments in raw materials, carrier systems and ingredients from the dermatological point of view. Especially active ingredients against skin‐aging, here in particular antioxidants and cell regulators, are reviewed. Important parameters for the quality of cosmetics and cosmeceuticals are evidence‐based in‐vivo and in‐vitro efficacy as well as scientifically proven wanted and unwanted effects.