Copper and sodium concentration in rat hair as related to dietary intake

The use of hair as an index of mineral status has received some criticism despite its wide use in research and its wider use as a diagnostic tool. This study evaluated the effect of dietary copper and sodium intake upon the concentration of these minerals in hair. Forty-eight Long-Evans rats were divided into 3 groups of 16 at weaning and fed one of three levels of copper; 1) low copper (LC), 2) marginal copper (MC) or 3 mg Cu/Kg feed, and 3) adequate copper (AC) or 8 mg/Kg feed. Rats were fed these diets ad libitum for 6 months. At day 100, half of the rats received 5% NaCl for 1 week followed by 1% NaCl for 11 weeks as drinking water. The other half received deionized-distilled water as drinking water. Results revealed that rats fed the AC diet had higher (p≤0.001) hair copper concentrations than rats fed the MC and LC diets. Rats fed the MC diet had higher (p≤0.001) hair copper concentrations than rats fed the LC diet. Higher hair sodium concentrations were found in rats consuming saline compared to rats consuming deionized-distilled water (p≤0.05). These results support the use of hair as a measure of mineral intake for populations.     

锌、铜对大鼠血脂水平影响的研究

用雄性断乳ｗｉｓｔａｒ大鼠研究了不同水平锌、铜对大鼠血脂水平的影响。结果显示：绝对或相对铜缺乏均引起血清胆固醇、甘油三酯浓度升高；而绝对或相对锌缺乏则主要引起高密度脂蛋白胆固醇（ＨＤＬ－Ｃ）和ＨＤＬ＿２－Ｃ浓度下降。相关分析表明：血清锌与ＨＤＬ－Ｃ、ＨＤＬ＿２－Ｃ呈明显正相关；血清铜与血清胆固醇、甘油三酯呈显著负相关。病理检查显示：除对照组外，其它各组主动脉组织形态均发生不同程度的病理改变，尤以高锌低铜、高铜低锌及低锌低铜组为著。提示在保持适宜铜水平的前提下，补充适量的锌以提高血清ＨＤＬ－Ｃ水平，可预防或延缓高脂血症的发生。     

AORTAL ABNORMALITIES IN MARGINAL COPPER DEFICIT

A diet containing 2 ppm of copper, fed to female rats through gestation/lactation and to male offspring to the age of 117 days, produced aortal abnormalities in the offspring.     

Dietary supplementation with t-butylhydroquinone reduces cardiac hypertrophy and anemia associated with copper deficiency in rats

The effect of dietary supplementation with the antioxidant, t-butylhydroquinone (TBHQ), on some of the cardiovascular consequences of copper deficiency was investigated. Rats were fed copper-deficient (CuD) diet containing 0.3 μg Cu/g of diet that were either nonsupplemented or supplemented with TBHQ (supplied in the dietary safflower oil at a concentration of 0.02%). Control rats were fed copper adequate (CuA) diet containing >5.0 μg Cu/g (CuA) that also were either nonsupplemented or supplemented with TBHQ. After five weeks, rats consuming CuD diet supplemented with TBHQ exihibited plasma copper concentrations, ceruloplasmin activities, and liver and heart copper concentrations that were significantly (P<0.05) lower than those of rats consuming either nonsupplemented or TBHQ supplemented CuA diet, but no different from those of rats consiming nonsupplemented CuD diet. However, rats consuming CuD diet supplemented with TBHQ had significantly (P<0.05) higher growth, hemoglobin concentrations, hematocrits, and red blood cell qistribution widths but lower heart weights than rats consuming nonsupplemented CuD diet. TBHQ supplementation had no effect on these variables in rats fed CuA diet. Thus, while TBHQ did not improve copper status, it did ameliorate the growth reduction, anemia, and cardiac hypertrophy associated with copper deficiency. These findings indirectly support the contention that oxidative damage contributes to the pathophysiological consequences of copper deficiency.     

镉对机体铜,锌含量的影响

作者研究了螺蛳对镉的生物富集,镉进入生物体后,体内铜水平明显下降。40只成年雌鼠分成5组,1组对照,4组染毒,所有染毒组给以40ppm(以Cd计)氯化镉溶液,其中三组分别再加铜、锌和铁。研究进行了共六个月。结果表明:对照组无异常发现,染毒组出现骨质疏松和皮质变薄,骨中铜水平明显下降。48只成年大鼠分成三组(雌雄各半),A组为对照组,B组喂以采自镉污染区的镉米,C组同样喂镉米再给10ppm(以Cd计)氯化镉溶液。实验共进行了两个月。染毒组骨锌明显下降。上述结果表明,镉所致缺铜或缺锌,在痛痛病发病机理中,可能是一个重要的因素。     

松花粉对前列腺增生大鼠体内微量元素锌、铜代谢的影响

目的观察马尾松花粉（松花粉）对前列腺增生大鼠体内微量元素代谢的影响。方法24只雄性Sprague-Dawley大鼠分为对照组、安慰剂组和松花粉组，每组8只。始终给对照组大鼠饲喂普通饲料；每日投料前分别给安慰剂组和松花粉组大鼠饲喂安慰剂（淀粉片）和松花粉片，3组大鼠的进食量完全相同。适应2周后开始给对照组大鼠肌肉注射橄榄油1ml·kg^-1·d^-1，给其余两组大鼠肌肉注射橄榄油配制的丙酸睾酮注射液4mg·kg^-1·d^-1，持续2周后停止注射。继续饲喂4周后将大鼠全部处死。取全血、肝脏和前列腺组织，称重前列腺组织，计算前列腺指数，用苏木精．伊红染色检测前列腺腺体增生情况，测定微量元素铜、锌的含量。结果松花粉组大鼠的前列腺重量[（1062．3±91．9）mg vs ．（1127．3±111．2）mg]及前列腺指数[（3．18±0．31）mg／g vs．（3．26±0．31）mg／g]均低于安慰剂组。安慰剂组前列腺腺体的乳头状增生比率（60．0％±10．0％）显著高于松花粉组（20．0％±10．0％）（P〈0．05）。两组的血清铜、锌含量均显著低于对照组（P〈0．05）。松花粉组大鼠的肝脏锌含量显著低于安慰剂组（P〈0．05），与对照组比较无显著差异；前列腺锌、铜含量均显著高于其他两组（P〈0．05）。结论松花粉对大鼠前列腺增生有明显抑制作用，调节体内微量元素锌、铜的代谢可能是其作用机理之一。     

Total body content of copper and other essential metals in rats fed fructose or starch

The effects of dietary carbohydrate and copper on whole body levels of copper and other essential minerals were investigated. Weaned male rats were pair-fed diets containing 62% fructose or cornstarch with either adequate (6–7 mg/kg) or deficient (0.5–0.7 mg/kg) copper (Cu) for 32–33 days. Recommended levels of other minerals were present in all diets. Total copper in whole body was approximately 2-fold higher in rats fed copper-supplemented diets than copper-deficient diets and was independent of the type of dietary carbohydrate. Whole body levels of zinc, iron, manganese and magnesium were independent of dietary copper and carbohydrate. Selenium content of rats fed copper-deficient diet with fructose was 35% higher than in those fed copper-adequate diet with fructose. Rats fed the copper-deficient diet containing starch had a whole body calcium level 17–23% lower than that of the other dietary groups. These results demonstrate that the copper-carbohydrate interaction is not a result of carbohydrate-dependent effects on the retention of dietary copper and other essential minerals.     

缺铜致大鼠高脂血症的研究

雄性断奶大鼠,随机分为两组,喂合铜饲料和缺铜饲料,饲养一个月。缺铜组大鼠体重增加少,血浆总蛋白和血红蛋白含量降低,血浆铜和动脉壁铜含量下降,同时出现血脂增高和单胺氧化酶活力降低。实验结果表明,食物缺铜可引起高胆固醇血症和含铜酶活力降低。     

饲料蛋白质水平对大鼠蛋白质、锌、铁和铜吸收利用的影响

Ｗｉｓｔａｒ纯品系断奶雄性大鼠３２只，随机分成４组，喂纯合成饲料。第１、２、３、４组饲料含蛋白质分别为５％、１０％、２０％和１０％，其它成份相同，第５０天只有第４组改喂以无氮饲科并与其它三组同样收集５天粪、尿，测定氮及锌、铁、铜的代谢量，第５６天处死大鼠，测毛和肝、肾、脑、睾丸、胫骨中锌、铁、铜的含量。结果表明：低蛋白质水平组影响大鼠体重增长和蛋白质代谢，机体组织锌、铁，铜含量降低，经粪便排出锌、铁量增加，锌和铁的吸收与存留显著降低。本文还对蛋白质营养水平不同所致的锌、铁、铜营养状况缺乏时毛中锌、铁、铜含量作为诊断指标的意义进行了探讨。     

缺铜对大鼠自由基防御系统酶组分和血清溶血素的影响

初断孔Wistar大鼠分别饲以缺铜(Cu0.49mg/kg)和含铜(Cu 6.44mg/kg)饲料52至57天。测定大鼠组织中自由基防御系統酶组分[超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GSIHPx)]活性、脂质过氧化物(LPO)含量和血清溶血素含量等。与对照组相比,缺铜大鼠红细胞及各脏器CuZoSOD活性显著降低,CAT和GSHPx活性无明显变化,亦未观察到自由基引起组织损伤的产物LDO的升高。提示,缺铜时机体自由基防御系统酶组分确实受到了一定程度的影响,但机体对自由基损伤的防御能力,总体上没有明显受损。缺铜大鼠血清溶血素显著下降,说明块铜影响了机体的体液免疫功能。实验结果还提示,作为反映机体铜营养状况的指标,CuZnSOD比血红蛋白更敏感。     

Effect of Copper and Selenium Supplementation on the Level of Elements in Rats’ Femurs under Neoplastic Conditions

A study was conducted to determine the effect of long-term supplementation with selenium and copper, administered at twice the level used in the standard diet of rats, on the content of selected elements in the femoral bones of healthy rats and rats with implanted LNCaP cancer cells. After an adaptation period, the animals were randomly divided into two experimental groups. The rats in the experimental group were implanted with prostate cancer cells. The rats in the control group were kept in the same conditions as those in the experimental group and fed the same diet, but without implanted cancer cells. The cancer cells (LNCaP) were intraperitoneally implanted in the amount of 1 × 10⁶ (in PBS 0.4 mL) at the age of 90 days. The content of elements in the samples was determined by a quadrupole mass spectrometer with inductively coupled plasma ionization (ICP-MS). In the femoral bones of rats with implanted LNCaP cells, in the case of the standard diet and the copper-enriched diet, there was a marked decreasing trend in the content of the analysed elements relative to the control rats. This may indicate slow osteolysis taking place in the bone tissue. Contrasting results were obtained for the diet enriched with selenium; there was no significant reduction in the level of these elements, and there was even an increase in the concentrations of Fe and K in the bones of rats with implanted LNCaP cells. Particularly, numerous changes in the mineral composition of the bones were generated by enriching the diet with copper. The elements that most often underwent changes (losses) in the bones were cobalt, iron, manganese and molybdenum. The changes observed, most likely induced by the implantation of LNCaP cells, may indicate a disturbance of mineral homeostasis.     

铜摄入量对大鼠动脉粥样硬化炎症因子影响

目的 探讨铜摄入量对大鼠动脉粥样硬化(arteriosclerosis,AS)相关炎症因子的影响。方法 选择Wistar大鼠饲以缺铜饲料并给予不同剂量葡萄糖酸铜30 d,以大鼠血中铜蓝蛋白(CP)为铜摄入量评价指标,分析其对大鼠AS相关炎症因子的影响。结果 大鼠血中CP活力为20.442～37.569 U/L时,C反应蛋白(CRP)可对铜摄入量过高或过低引发的AS作出预警;铜摄入量低于或高于日常摄入量时,同型半胱氨酸(HCY)水平均高于对照组(P<0.05);CP活力超出30.279～37.569 U/L时,各组细胞间粘附因子-1(ICAM-1)水平均明显高于正常对照组(P<0.05);CP活力超出20.442～37.569 U/L时,各组单核细胞趋化因子-1(MCP-1)水平均高于正常对照组(P<0.05)。结论 铜摄入量过高或过低均可不同程度激活AS相关各炎症因子,有引起AS的潜在风险。     

缺锌和补锌对大鼠血清锌、铜及血脂水平影响的研究

健康雄性Ｗｉｓｔａｒ大鼠４５只，先进行２５天锌缺乏实验，继之２１只大鼠再进行１５天锌补充实验。结果显示，缺锌可致大鼠血清总胆固醇（ＴＣ）及低密度脂蛋白胆固醇（ＬＤＬ－Ｃ）含量增高，而血清锌（Ｚｎ）、高密度脂蛋白胆固醇（ＨＤＬ－Ｃ）及其亚组分ＨＤＬ２－Ｃ含量明显下降，并且血清Ｚｎ含量与上述各指标均呈很好的剂量反应关系。适量补锌（１２ｍｇ／ｋｇ和３０ｍｇ／ｋｇ）均可使大鼠的各项指标完全恢复，而大剂量补锌（２５０ｍｇ／ｋｇ）则使ＨＤＬ－Ｃ及ＨＤＬ２－Ｃ有延迟恢复的趋向。血清铜（Ｃｕ）含量始终无明显改变。提示，膳食锌含量缺乏可致血脂代谢紊乱，而大剂量补锌又可使血脂恢复延迟，因此，膳食中Ｚｎ含量应有适当的剂量范围。     

Hepatic fatty acid synthesis and triglyceride secretion in rats fed fructose- or glucose-based diets containing corn oil, tallow or marine oil

The effects of three dietary fats, corn oil (CO), tallow (T) and marine oil (MO), on serum triglycerides, hepatic lipogenic enzyme activity and lipogenesis in vivo using 3H2O were measured in fed and fasted rats that had been consuming diets in which the carbohydrate was either glucose or fructose. Hepatic triglyceride secretion was also measured in fasted rats fed the same diets. In both the fed and fasted state, hepatic enzyme activity and lipogenesis in vivo were greater in fructose-fed rats than in glucose-fed rats and less in both CO- and MO-fed rats than in T-fed rats. In rats fed glucose, serum triglycerides were lower in fasted rats fed MO than in fasted rats fed CO. In rats fed glucose or fructose, hepatic triglyceride secretion was lower in rats fed MO than in those fed CO or T.     

Effects of amylomaize starch on mineral metabolism in the adult rat: role of the microflora

The effects of amylomaize starch on rat mineral metabolism were studied. To elucidate the role of bacterial fermentation, the effects of amylomaize starch were compared in germfree (GF) and conventional (CV) rats. A purified diet, sterilized by irradiation and containing either maize starch (M) or amylomaize starch (A), was fed to the rats. Feed intake was similar in all groups of rats except GF rats fed amylomaize starch ad libitum, whose feed intake was higher. One group of GF rats received amylomaize starch in restricted amounts (pair-fed rats). A balance study of energy, nitrogen and minerals (Ca, P, Mg, Na, K, Fe, Mn, Zn and Cu) was performed. Apparent absorption of Mg, P, Na, K and Zn (expressed as a percentage of the amount ingested) was lower in GF rats fed amylomaize starch than in GF rats fed maize starch. Since feed intake was higher in GF rats fed amylomaize starch ad libitum than in rats fed maize starch, mineral absorption (expressed in milligrams per day) was not reduced in rats fed ad libitum, whereas it was reduced in pair-fed rats. Mineral retention was similar in GF rats fed ad libitum, but was reduced in pair-fed rats. In CV rats fed amylomaize starch, cecal weight and cecal volatile fatty acids concentration were higher than those in CV rats fed maize starch. Apparent absorption of N and P was lower and that of Ca, Mg and Fe was higher in CV rats fed amylomaize starch than in rats fed maize starch.(ABSTRACT TRUNCATED AT 250 WORDS)     

Zinc supplementation of optimal and suboptimal protein diets 2. Responses of young rats fed protein combinations

The effect of zinc supplementation on the utilization of combination protein sources by and the bioavailability of trace minerals to young rats was studied. Protein combinations included corn meal/soybean meal (CM/SM) and whole wheat/dried egg white solids (WW/EW) formulated to provide protein levels of 7.5% and 15%. Each diet was fed with and without zinc supplements (0, 50, or 100 ppm). Animals were maintained on the experimental diets for 4 weeks, and criteria used for the evaluation included weight gain, hemoglobin concentration, and liver deposition of copper, iron, and zinc. Zinc supplements did not stimulate growth in young rats fed suboptimal levels of either protein combination, and zinc did not appear to be a limiting nutrient in the utilization of a marginal protein level in this study. In this study zinc supplementation had varying effects on the apparent bioavailability of copper or iron, but no general trends were observed. There is the possibility that the effect of zinc on trace mineral availability was influenced by the presences of other dietary factors, such as type and amount of fiber or the presence of phytates, inherent with the types of protein combinations used in the study. As the level of zinc in the diet increased, the amount of zinc accumulating in the liver tended to increase.     

Influence of dietary fiber on lipid metabolism in meal-fed rats

The effects of the four major components of dietary fiber--cellulose, hemicellulose, pectin and lignin--on lipid metabolism were studied in meal-fed Wistar rats maintained on a cholesterol-free semipurified diet for 21 days. Transit time was decreased and fecal weight increased compared to rats fed a fiber-free diet. Rats fed cellulose or lignin gained significantly less weight than rats fed hemicellulose or pectin. The fibers had no effect on serum cholesterol levels, but serum triacylglycerol levels were significantly higher in rats fed cellulose. Liver cholesterol levels were higher in cellulose-fed rats but liver triacylglycerol levels were highest in rats fed hemicellulose or pectin. Hepatic cholesterol 7 alpha-hydroxylase and HMG-CoA reductase activities were highest in rats fed cellulose and pectin, respectively. Epididymal fat cell size was similar in all groups but fat cell number was highest in pectin-fed rats. Perirenal fat cell size was greatest in rats fed cellulose or lignin and fat cell number in rats fed cellulose or hemicellulose. Lipoprotein lipase activity (per 10(6) cells) was elevated in epididymal fat of rats fed pectin and in perirenal fat of rats fed hemicellulose. Carcass lipid accumulation was highest in rats fed cellulose or lignin. Rats fed cellulose accumulated significantly higher levels of carcass cholesterol and triacylglycerol. Of the fibers fed, cellulose led to an accumulation of serum, liver and carcass lipid. The four fibers fed represent purified and altered forms of cellular components and the observed effects cannot be extrapolated to diets containing foods rich in one or another of these components.     

Diet composition alters the acceptance of fat by rats

The acceptance of dietary fat by rats is influenced by changes in fat digestion and metabolism. In these experiments, rats were fed diets that differed in fat, carbohydrate and fiber content, and the acceptance of fat was measured. Rats fed a high fat (HF) diet ate more corn oil in 30-min or 6-h tests than did rats fed an isocaloric high carbohydrate (HC) diet. This effect was seen after the diets were switched and rats retested. Differences in dietary fiber between the isocaloric HF and HC diets did not account for this effect because rats fed HF diets, either high or low in fiber content, drank more oil than rats fed the HC diet. Rats fed the HF diet with added carbohydrate drank less oil than rats fed the HF diet, and the same amount of oil as rats fed the HC diet. Compared with rats fed the HC diet, rats fed the HF diet drank more oil in a two-bottle preference test with sucrose or when mixed with sucrose in a single-bottle test. Rats offered a variety of fats, sugars or other test foods, ate more nutritive liquid fats and some solid fats, but did not eat more sugar or other items if they were fed the HF diet rather than the HC diet. These studies taken together strongly suggest that rats fed a high fat diet show a greater acceptance of fat compared with rats fed a high carbohydrate diet.     

The effect of taurine on plasma cholesterol concentration in genetic type 2 diabetic GK rats

The purpose of this study is to investigate the effect of taurine on the plasma cholesterol concentration in genetic type 2 diabetic rats fed cholesterol-free or high-cholesterol diets. Diabetic rats (GK male rats) and normal rats (Wistar male rats) were fed either a cholesterol-free or cholesterol-enriched (1% cholesterol + 0.25% sodium cholate) diet supplemented with or without 3% taurine for 21 or 14 d. Compared to the normal rats, diabetic rats showed a high glucose concentration in their blood and plasma, but it was not affected by taurine feeding. The plasma insulin concentration was higher in the diabetic rats than in the normal rats. At the start of the experiment, the plasma cholesterol concentration was significantly higher in the diabetic rats than in the normal rats. Taurine did not affect the plasma cholesterol level in rats fed the cholesterol-free diet. However, taurine feeding significantly increased the plasma HDL-cholesterol concentration in the diabetic rats fed the cholesterol-free diet. In both the diabetic and normal rats fed the cholesterol diet, the plasma cholesterol concentration was significantly lower in rats fed the diet supplemented with taurine than in the rats fed the control diet. It was concluded that taurine has a hypocholesterolemic effect in both diabetic and normal rats fed diets containing cholesterol. Moreover, these results suggest that taurine seems to affect the HDL-cholesterol metabolism in diabetic rats fed a cholesterol-free diet.     

Dietary amino acid analogues and transport of lysine or valine across the blood-brain barrier in rats

Studies were undertaken to determine if dietary disproportions of amino acids would alter flux into brain of the amino acid present in the diet in a growth-limiting concentration. Rats were adapted to a lysine-limiting diet before receiving a meal of this control diet, alone or with added lysine or homoarginine (a competitor for lysine transport) or both, before intravenous infusion of [14C]lysine. The brain-to-plasma radioactivity ratio was lower in rats fed extra lysine or homoarginine than in rats fed the control diet, whereas lysine flux and brain lysine concentration were high in rats fed extra lysine alone. Flux and concentration were lower in rats fed homoarginine + lysine than in rats fed extra lysine alone. Other rats were fed a valine-limiting diet containing added valine, norleucine (a competitor for valine transport) or both, before [14C]valine was infused. Valine flux and brain valine concentrations were higher in rats fed extra valine than in control rats, whereas flux was lower in the group fed norleucine alone. Valine flux was higher in rats fed norleucine + valine than in the rats fed norleucine alone. Our studies show that dietary disproportions of amino acids can alter the flux of specific amino acids across the blood-brain barrier.