Influence of eicosapentaenoic acid and vitamin E on hepatic hydroxyproline content in rabbits fed cholesterol-rich diet

The effect of eicosapentaenoic acid (EPA) and vitamin E on hepatic hydroxyproline content, as an index of collagen was examined in rabbits receiving cholesterol rich diets for a period of 45 days. Rabbits were divided as control (A) and cholesterol fed groups (B, C, D). Group C received 80 mg. of EPA and group D received 100 IU of vitamin E daily in addition to the cholesterol rich diet (2% w/w) which was solely given to group B. The maintenance of rabbits on high cholesterol diets resulted in significantly increased liver cholesterol concentrations. This effect was most pronounced in rabbits receiving cholesterol alone. Hepatic triglyceride levels remained unchanged in all cholesterol-fed rabbits, but total phospholipid levels in liver significantly decreased in EPA and vitamin E supplemented rabbits. An interesting finding was the increase in hepatic hydroxyproline content in rabbits following the administration of EPA and vitamin E to cholesterol rich diet.     

2,3,7,8-四氯二苯并二噁英急性染毒对小鼠脑组织中Na+-K+-ATP酶和Ca2+-ATP酶活力的影响

目的 研究2,3,7,8-四氯二苯并二噁英(TCDD)对小鼠脑组织中Na+-K+-ATP酶、Ca2+-ATP酶活力的影响.方法 将48只雌雄各半的昆明种小鼠按性别随机分为高、中、低剂量TCDD染毒组和对照组,每组雌雄各6只,TCDD染毒剂量分别为100、10、1 μg/kg,用腹腔注射的方式一次染毒,48 h后,测定脑组织中Na+-K+-ATP酶、Ca2+-ArrP酶活力.结果 雌性低剂量、中剂量染毒组和雄性高剂量染毒组小鼠脑组织中Na+-K+-ATP酶活力[分别为(17.35±3.07)、(16.13±2.42)、(20.25±2.72)μmolPi·mg pro-1·h-1]明显升高,与对照组[分别为(13.60±1.72)、(15.97±1.90) μmol Pi·mg pro-1·h-1相比,差异均有统计学意义(P<0.05).各染毒组小鼠Ca2+-ATP酶活力有增加的趋势,但与对照组比较,差异无统计学意义(P>0.05).结论 TCDD急性染毒能提高小鼠脑组织中Na+-K+-ATP酶的活力,且存在性别差异.     

2,3,7,8-四氯二苯并二噁英急性染毒对小鼠脑组织中Na+-K+-ATP酶和Ca2+-ATP酶活力的影响

目的 研究2,3,7,8-四氯二苯并二噁英(TCDD)对小鼠脑组织中Na+-K+-ATP酶、Ca2+-ATP酶活力的影响.方法 将48只雌雄各半的昆明种小鼠按性别随机分为高、中、低剂量TCDD染毒组和对照组,每组雌雄各6只,TCDD染毒剂量分别为100、10、1 μg/kg,用腹腔注射的方式一次染毒,48 h后,测定脑组织中Na+-K+-ATP酶、Ca2+-ArrP酶活力.结果 雌性低剂量、中剂量染毒组和雄性高剂量染毒组小鼠脑组织中Na+-K+-ATP酶活力[分别为(17.35±3.07)、(16.13±2.42)、(20.25±2.72)μmolPi·mg pro-1·h-1]明显升高,与对照组[分别为(13.60±1.72)、(15.97±1.90) μmol Pi·mg pro-1·h-1相比,差异均有统计学意义(P<0.05).各染毒组小鼠Ca2+-ATP酶活力有增加的趋势,但与对照组比较,差异无统计学意义(P>0.05).结论 TCDD急性染毒能提高小鼠脑组织中Na+-K+-ATP酶的活力,且存在性别差异.     

2,3,7,8-四氯二苯并二噁英急性染毒对小鼠脑组织中Na+-K+-ATP酶和Ca2+-ATP酶活力的影响

目的 研究2,3,7,8-四氯二苯并二噁英(TCDD)对小鼠脑组织中Na+-K+-ATP酶、Ca2+-ATP酶活力的影响.方法 将48只雌雄各半的昆明种小鼠按性别随机分为高、中、低剂量TCDD染毒组和对照组,每组雌雄各6只,TCDD染毒剂量分别为100、10、1 μg/kg,用腹腔注射的方式一次染毒,48 h后,测定脑组织中Na+-K+-ATP酶、Ca2+-ArrP酶活力.结果 雌性低剂量、中剂量染毒组和雄性高剂量染毒组小鼠脑组织中Na+-K+-ATP酶活力[分别为(17.35±3.07)、(16.13±2.42)、(20.25±2.72)μmolPi·mg pro-1·h-1]明显升高,与对照组[分别为(13.60±1.72)、(15.97±1.90) μmol Pi·mg pro-1·h-1相比,差异均有统计学意义(P<0.05).各染毒组小鼠Ca2+-ATP酶活力有增加的趋势,但与对照组比较,差异无统计学意义(P>0.05).结论 TCDD急性染毒能提高小鼠脑组织中Na+-K+-ATP酶的活力,且存在性别差异.     

Effect of simultaneous administration of vitamin E and pyridoxine on erythrocyte membrane Na+K+ ATPase activity

Vitamin E is known to have an interaction with pyridoxine. To understand the functional significance of this interaction a study was carried out on the effect of simultaneous administration of vitamin E and pyridoxine on erythrocyte membrane Na+K+ ATPase activity. Adult male volunteers belonging to low socio-economic class with prior consent were used as subjects for the study. The results of the study have shown that administration of vitamin E alone brings about a transient increase in the total and ouabain insensitive Na+K+ ATPase. Administration of B6 along with vitamin E brought about an increase in the total and true Na+K+ ATPase activity. B6 administration alone showed a statistically insignificant increase in true ATPase activity. The results of the study are interpreted to show that administration of vitamin E along with B6 is beneficial to membrane function.     

Hypocholesterolemic effect of vitamin E on cholesterol-fed rabbit

Serum cholesterol level increased sharply in rabbits fed an atherosclerosis-promoting diet containing 0.25% or 0.5% cholesterol. Oral supplementation with 2100 IU of vitamin E per week manifested a hypocholesterolemic effect only after four weeks, with 50% reduction attained on the 8th week. Changes in low density and very low density lipoprotein cholesterol levels paralleled those in the serum. Liver total cholesterol level and the ratio of free to ester forms were not different between vitamin E-supplemented and nonsupplemented rabbits, whereas a 4-5 fold increase in hepatic cholesterol-7 alpha-hydroxylase activity, elevation of bile salt concentration and improvement in bile lithogenic index were observed in the vitamin E-supplemented groups.     

Enhancement of Ca2+-sensitive myosin ATPase activity by cadmium

The effects of Cd²⁺ on Ca²⁺-sensitive myosin ATPase activity were examined. In the absence of Ca²⁺, the Ca²⁺-dependent myosin ATPase activity was enhanced by Cd²⁺ to the same extent as with Ca²⁺ at concentrations ranging from 10⁻⁶ to 10⁻³ M. At 10⁻² M, however, no activation was observed. Zn²⁺, Co²⁺, and Sr²⁺ also activated the myosin ATPase. Sr²⁺ and Co²⁺ were less effective. Hg²⁺, Cr³⁺, and Cu²⁺ were essentially inactive. In the presence of below 10⁻³ M Ca²⁺, the increase in the enzyme activity observed on the addition of Cd²⁺ was in addition to that caused by Ca²⁺ alone. The ability of metal ions to activate myosin ATPase was compared with that to activate calmodulin-dependent cAMP phosphodiesterase. The activating effects of the metal ions tested were in the order of Ca²⁺ > Cd²⁺ > Zn²⁺ > Co²⁺ > Sr²⁺ for Ca²⁺-sensitive myosin ATPase and Ca²⁺ > Cd²⁺ > Sr²⁺ > Zn²⁺ > Hg²⁺ > Co²⁺ for cAMP phosphodiesterase. Cd²⁺ activated both enzyme activities most efficiently among the metal ions tested except Ca²⁺. These results indicate that Cd²⁺ is able to substitute for Ca²⁺ in the case of Ca²⁺ dependent enzymes, regardless of whether or not calmodulin participates in the activating process.     

库存血液在室温及37℃预热时钠钾ATP酶和钙镁ATP酶活性变化

目的:为了解库存血液在室温25℃及37℃水浴预热时Na -K ATP酶和ca2 -Mg2 ATP酶活性的变化,给大量输血病人血液预热提供指导.方法:应用比色法分别检测45例合格的库存血液,在不同温度下红细胞膜Na -K ATP酶和Ca2 -Mg2 ATP酶活性,并对结果进行分析.结果:室温25℃30 min红细胞膜Na -K ATP酶活性为0.0143±0.00328(μmol·Pi/107RBC·h),Ca2 -Mg2 ATP酶活性为0.0129±0.00401(μmol·Pi/107 RBC·h);室温25℃ 2 h红细胞膜Na -K ATP酶活性为0.0142±0.00305(μmol·Pi/107 RBC·h),Ca2 -Mg2 ATP酶活性为0.0132±0.00307(μmol·Pi/107 RBC·h);37℃10 min红细胞膜Na -K ATP酶活性为0.0152±0.00374(μmol·Pi/107 RBC·h),ca2 -Mg2 ATP酶活性为0.0131±0.00515(μmol·Pi/107 RBC·h).结论:库存血液预热能使红细胞膜Na -K ATP酶和ca2 -Mg2 ATP酶活性明显升高.     

维生素E对大鼠肝线粒体酶活性的影响

目的观察维生素E（VE）补充对大鼠肝线粒体ATP酶和抗氧化酶活性的影响。方法Wistar大鼠随机分成4组，对照组、VE1、VE2和VE3干预组；对照组给予普通饲料，3个干预组均喂饲添加维生素E的饲料，剂量分别为335，1340，5025mg／kg饲料，喂养10周后，摘取肝脏提取线粒体，测定Na^＋-K^＋-ATP酶、Ca2^＋-Mg^＋-ATP酶、谷胱甘肽过氧化物酶（GSH—Px）、超氧化物歧化酶（SOD）的活性及丙二醛（MDA）的含量。结果VE1组与对照组相比，SOD、GSH—Px、Na^＋-K^＋-ATP酶、Ca2^＋-Mg2^＋-ATP酶活性显著升高（P〈0．05），MDA水平显著降低（P〈0．05）。VE2、VE3组与对照组相比未见改善。VE2、VE3和VE1组相比，SOD、GSH—Px、Na^＋-K^＋-ATP酶、Ca2^＋-Mg^＋-ATP酶活性显著降低（P〈0．05），MDA水平显著升高（P〈0．05）。结论补充适量VE（335mg／kg）能显著增强大鼠肝线粒体ATP酶活性及氧化能力；较高剂量VE；（1340，5025mg／kg）组未能改善大鼠肝线粒体ATP酶活性及抗氧化能力。     

Hypolipidemic activity of Allium porrum L. in cholesterol-fed rabbits

Allium porrum L. is a herbaceous plant from the Liliaceae family and has been widely used in Persian foods as a flavor component and in Iranian traditional medicine as an anti-atherogenic remedy. The present investigation was undertaken to evaluate the antihypercholesterolemic effect of a hydroalcoholic extract of A. porrum L. bulbs. Rabbits were divided into five groups--control, hypercholesterolemic control, and three treatment groups (hypercholesterolemic diet + 250, 500, or 1,000 mg/kg of body weight of extract, respectively)--and were fed for 12 weeks. Blood samples were obtained to analyze plasma cholesterol, triglycerides, and low-density lipoprotein (LDL), very LDL, and high-density lipoprotein (HDL) cholesterol. Body weight increased in all groups throughout the treatment without significant differences among them. Plasma total cholesterol increased with respect to the control in the positive control group at the end of the treatment. Plasma total cholesterol decreased in all groups treated with A. porrum extract in a dose-dependent fashion. Changes in the distribution of cholesterol in HDL or LDL were found, and LDL cholesterol decreased significantly in all of the groups treated with A. porrum extract with respect to the hypercholesterolemic group. Thus, these findings indicate that this plant may be useful for the treatment of hypercholesterolemia.     

镉对体外培养肾组织中Ca2+-ATPase的影响及尼莫地平的干预作用

目的 探讨镉对肾组织中Ca2+-ATPase的影响及尼莫地平(Nimo)对其的干预作用. 方法 在体外条件下,测定CdCl2对肾组织Ca2+-ATPase及乳酸脱氢酶(LDH)、碱性磷酸酶 (ALP)、尿N-乙酰-D-氨基葡萄苷酶(NAG)等多种肾损伤标志酶活力的作用及N imo干预处理后的影响.结果在低浓度CdCl2组,Ca2+-ATPase的活力明显升高,100 mg/L CdCl2组Ca2+-ATPase的活力为(42.12±3.35)μmol Pi.g-1 .h-1,与对照组[(31.23±2.59)μmol Pi.g-1.h-1]的差异有显著性(P＜0.05);而随CdCl2浓度升高,Ca2+-ATPase活力受到明显抑制, 200 mg/L CdCl2组的Ca2+-ATPase活力为(20.67±2.46)μmol Pi.g-1.h -1,明显低于对照组,差异有显著性(P＜0.05).而染镉前经Nimo预处理后,200 mg/L CdCl2+Nimo组的NAG活力,100、150、200 mg/L CdCl2+Nimo组的LDH活力及150、200 mg/L CdCl2+Nimo组的ALP活力均低于单纯染CdCl2组,差异有显著性( P＜0.05);100 mg/L CdCl2+Nimo组的Ca2+-ATPase活力低于、而200 mg /L CdCl2+Nimo组则高于单纯CdCl2组,差异均有显著性(P＜0.05). 结论 CdCl2对Ca2+-ATPase活力的影响是双相的,Nim o可部分解除CdCl2对Ca2+-ATPase活力的抑制,并具有减轻镉性肾损伤的能力 .     

Erythrocyte lipid peroxidation, glutathione and vitamin E levels in cholesterol-fed rats

Erythrocyte cholesterol and phospholipid levels, the susceptibility of erythrocytes to lipid peroxidation as well as erythrocyte glutathione and vitamin E levels were determined in rats fed a high cholesterol (2%, w/w) and high cholic acid (0.5%, w/w) diet for 3 months. Cholesterol feeding caused an increase in erythrocyte cholesterol levels, but no change was observed in erythrocyte phospholipid levels. Dietary cholesterol did not alter the susceptibility of erythrocytes to lipid peroxidation as well as erythrocyte glutathione and vitamin E levels in rats.     

Interactive effect of hesperidin and vitamin E supplements on cholesterol metabolism in high cholesterol-fed rats

Certain bioflavonoids are potent antioxidants and have pharmacologic effects similar to those of vitamin E. Accordingly, the interactive effect of hesperidin and vitamin E was studied with respect to cholesterol metabolism and the antioxidant status. Hesperidin supplement (0.1%, wt/wt) with comparable levels of vitamin E was provided with a high-cholesterol (1%, wt/wt) diet to rats for 5 weeks. The amount of vitamin E included in the hesperidin-free and hesperidin diets was either a low (low-E) or a normal (normal-E) level. The hesperidin supplement and different levels of dietary vitamin E did not significantly alter the concentrations of plasma triglycerides. However, the inclusion of hesperidin significantly lowered the concentration of plasma cholesterol in both the low-vitamin E group and the normal-vitamin E group compared to the hesperidin-free groups (p < 0.05). The hepatic triglyceride content was significantly lowered by the hesperidin supplement, as opposed to the plasma triglyceride content, regardless of the vitamin E level in the diet. The hepatic HMG-CoA reductase activity was significantly lowered by the hesperidin supplement with both the low-vitamin E and the normal-vitamin E compared to the hesperidin-free groups (p < 0.05). The hepatic HMG-CoA reductase activity was also significantly lowered with an increase in the dietary vitamin E within the hesperidin and hesperidin-free groups. The excretion of fecal neutral sterol and acidic sterols tended to be lower with the hesperidin supplement. Neither dietary hesperidin nor vitamin E significantly changed the hepatic antioxidant enzyme activity. This data indicates that hesperidin lowers the concentration of plasma cholesterol and the hepatic triglyceride content regardless of the dietary vitamin E level. However, the concentration of plasma cholesterol in the hesperidin-free groups was dependent on the dietary vitamin E level. This information may contribute to understanding the interactive effect of hesperidin and vitamin E on cholesterol biosynthesis in high cholesterol-fed rats.     

Influence of dietary fat, vitamin E, ethoxyquin and indomethacin on the synthesis of prostaglandin E2 in brain regions of mice

The regional brain synthesis of prostaglandin E2 (PGE2) of rats varies with age and dietary vitamin E. We investigated ex-vivo synthesis of PGE2 in brain regions of 24-mo-old male C57BL/6Nia mice. Mice were fed semipurified diets containing 1) 5% by weight of vitamin E-stripped corn oil, nonhydrogenated coconut oil or fish oil, or 2) 3.8% lard + 1.2% stripped corn oil (control), each supplemented with 30 or 500 mg of vitamin E per kg for 6 wk. In addition, two groups of mice were fed control diets containing 2500 mg of ethoxyquin/kg or 1 mg of indomethacin/(kg.day). Mice fed fish oil had lower (P less than 0.01) plasma alpha-tocopherol than those fed coconut oil. Vitamin E supplementation had no effect on the concentration of alpha-tocopherol in most brain regions. The rank order of PGE2 synthesis among all groups was cerebrum = cerebellum greater than midbrain greater than brainstem. Vitamin E supplementation tended to reduce brain PGE2 synthesis. Fat with 30 mg/kg of vitamin E in their diet. In the brainstem, fish oil significantly reduced PGE2 relative to mice fed corn oil. Ethoxyquin lowered plasma alpha-tocopherol by 42% and reduced the PGE2 synthesis in brain regions, and indomethacin reduced it by 50%. Thus, ethoxyquin and indomethacin significantly reduced the brain's regional capacity for PGE2 synthesis, whereas vitamin E was not effective for the period tested. The reduction of PGE2 synthesis in the brain with fish oil feeding in this study was not as notable as reported for other tissues unless combined with high-dose vitamin E supplementation.     

铝对大鼠大脑皮层和海马神经细胞钙浓度影响

目的探讨染铝大鼠中枢神经系统中大脑皮层和海马神经细胞内游离钙浓度([Ca^2 ]i)的动态变化及可恢复性。方法对wistar大鼠进行亚慢性染毒，分别在染毒第45，75，120d和染毒结束后30d，应用钙离子荧光指示剂Fura-2／AM测定大鼠大脑皮层和海马神经细胞[Ca^2 ]i。结果中剂量组(74．7mg／kg)在染毒的各个时期内均表现为[Ca^2 ]i高于对照组，而高剂量组(248．7mg/kg)在染毒的第120d才表现为[Ca^2 ]i明显增高，低剂量组(37．3mg／kg)在各个染毒时期与对照组相比均无显著性差异。在停止接触铝30d后，各实验组与对照组相比无显著性差异，并且高、中剂量组表现出[Ca^2 ]i有降低的趋势。结论铝可通过逐渐增加大脑皮层和海马神经细胞内游离钙浓度([Ca^2 ]i)而发挥神经毒性作用。     

除虫菊酯类农药对大鼠肝线粒体、微粒体~(45)Ca摄取的影响

为探讨除虫菊酯类农药对钙离子转运的影响，采用体外放射性同位素４５Ｃａ测定技术，观察了溴氰菊酯、氯氰菊酯对雄性ＳＤ大鼠肝线粒体、微粒体４５Ｃａ主动摄取的影响，以及对线粒体、微粒体Ｃａ２＋－ＡＴＰ酶活力的影响。结果表明：溴氰菊酯、氯氰菊酯均能明显降低大鼠肝线粒体、微粒体４５Ｃａ主动摄取的能力，抑制肝线粒体、微粒体Ｃａ２＋－ＡＴＰ酶的活力，与对照组相比，差异均有显著或非常显著意义（Ｐ＜０．０５或Ｐ＜０．０１），且随剂量增加，线粒体、微粒体４５Ｃａ摄取率及Ｃａ２＋－ＡＴＰ酶的活力有显著下降的趋势。提示：溴氰菊酯、氯氰菊酯对肝脏钙稳态影响的作用部位主要是线粒体和内质网钙隔离和调节系统，使其钙封闭作用失调、钙离子转运障碍、细胞正常生理生化功能紊乱。     

Ca2+-Mg2+ ATPase of mouse cardiac sarcoplasmic reticulum is affected by membrane n-6 and n-3 polyunsaturated fatty acid content

White mice, 18-20 g, were fed purified diets containing two weight percent safflower oil plus ten weight percent menhaden, corn, or olive oil for 2 wk. Menhaden oil ingestion resulted in significantly higher levels of 22:6(n-3) and 20:5(n-3), particularly 22:6(n-3), and lower levels of 20:4(n-6) and 18:2(n-6) in cardiac sarcoplasmic reticulum (SR) phospholipids than did corn or olive oil ingestion. These changes in fatty acid composition resulted in a significant decrease in the value of the n-6/n-3 fatty acid ratio of cardiac SR phospholipids. The ratio was 2.8 versus 0.2 in choline phospholipids and 1.9 versus 0.2 in ethanolamine phospholipids in SR of mice fed corn or menhaden oil, respectively. This reduction in the n-6/n-3 fatty acid ratio was associated with a lower relative activity of Ca2+-Mg2+ ATPase, and a lower initial rate of calcium transport and maximum calcium uptake in SR vesicles from mice fed menhaden oil rather than olive or corn oils. The specific activity of NADPH cytochrome C reductase (EC 1.6.2.3) of cardiac SR was not affected by dietary lipids. These data indicate that modification of SR by 22:6(n-3) may change the SR bilayer structure resulting in alteration of the calcium transport properties of SR vesicles. In addition, our results suggest that reduction of calcium flux across cardiac SR following fish oil consumption may also reduce the susceptibility of myocytes to rapid changes in calcium concentrations which may occur during ischemia and reperfusion.     

太极拳运动对中老年人红细胞膜Na+-K+ATP酶和Ca2+-Mg2+ATP酶活性的影响

目的：探讨太极拳运动对中老年人红细胞膜Na^ -K^ ATP酶和Ca^2 -Mg^2 ATP酶活性的影响。方法：选取64名练习太极拳的中老年人为观察组，另选47名很少参加体育锻炼者为对照组，采两组研究对象的静脉血，检测Na^ -K^ ATP酶和Ca^2 -Mg^2 ATP酶的活性。结果：观察组2种ATP酶活性均高于对照组（P＜0．01）；性别间差异无显著性（P＞0．05）；2种酶活性均与练拳时间呈正相关（P＜0．05）。结论：太极拳运动能提高中老年人红细胞膜Na^ -K^ ATP酶和Ca^2 -Mg^2 ATP酶活性，改善细胞代谢功能，练拳时间越长，效果越好，从而促进健康，延缓衰老。     

Influence of vitamin E on physical performance

There are two properties of vitamin E which are leading to its use for better physical performance. On one side it promotes an economical energy metabolism, on the other side it acts as a stabilizing antioxidant in membranes. One group of 6 high altitude mountain climbers was substituted with 2 x 200 mg dl-alpha-tocopheryl acetate and a second of 6 were given placebos during a 10 weeks expedition. The influence on the synthesis of lactic acid and on the exhalation of pentane was investigated. After 2 weeks the anaerobic threshold (AT) was higher in both groups. In the course of the experiment the AT of the treatment group increased further whereas the AT of the control group decreased significantly (p less than 0.01). Pentane exhalation, considered to be a measure for lipid peroxidation, showed no significant change after a 4 weeks substitution with vitamin E in the treatment group, but in the control group the exhaled pentane was more than 100% higher. The difference is significant, too (p less than 0.01). The results of this study show that vitamin E has a beneficial effect on physical performance and on cell protection, at least at high altitude.