Favism-like effects of divicine and isouramil in the rat: Acute and chronic effects on animal health,mortalities, blood parameters and ability to exchange respiratory gases

In vivo and in vitro experiments were carried out to establish the effects of divicine (DV) and isouramil (IU) on the rat when administered intra-peritoneally (IP). The LD₅₀for DV and IU was 148 and 183 mg kg^?1 body weight, respectively. There was a high negative correlation between the amount of DV added in vitro to blood and the blood glutathione (GSH) concentration, the hemoglobin absorbance ratio (576 nm/630 nm) and the erythrocyte sedimentation rate. The same relationships occurred in vivo, with mortalities also being highly correlated with these factors. Intravenously injected DV completely disappeared from the blood within a few minutes, indicating a very short half-life. The concentration of glutathione (GSH) in the red blood cells (RBC) was much higher and affected to a much greater degree in vivo by D V compared with GSH in the plasma. In the fourth experiment successive sub acute injections of DV and IU increased spleen weight and adrenal weights (IU only) and reduced kidney weights. Packed cell volume, hemoglobin concentration, leucocytes, lymphocytes, monocytes, and urea-N were also affected. Blood gas analyses in the fifth study showed that both DV and IU markedly reduced the partial pressure of oxygen in the blood, the per cent oxygen saturation, the pH and the bicarbonate concentration. This suggests that these compounds impaired the functional capacity of the RBC. The concentration of GSH was lower in RBC from young rats, and young rats, as compared with more mature rats, were considerably more sensitive to the toxic effects of DV. This work provides direct evidence, for the first time, on many of the adverse effects of these compounds.     

Effects of intraperitoneally injected vicine and convicine on the rat: Induction of favism-like signs

Rats were injected intraperitoneally with single or several successive doses of vicine or convicine. Single injections of these compounds at different concentrations caused increased respiration rates, generalised cyanosis, abdominal convolutions and, after several hours, death which appeared to be caused by asphyxiation. The tissues of the dead animals were engorged with dark brown blood and the large intestine and caecum contained entrapped gases and watery digesta and faecal matter. A second study demonstrated that injected vicine and convicine were cleared from the intraperitoneal cavity over several hours via the kidney and large intestine and that they were cleaved in the digesta of the large intestine and colon to divicine and isouramil. In a third study, rats were injected daily for 10 days with vicine or convicine. There were increases in spleen weight and blood monocytes and neutrophil counts and decreases in liver weight, blood glutathione and glucose concentrations, and lymphocyte counts. Blood from rats pretreated in vivo with convicine was shown to have an altered ultraviolet absorbance pattern. A similar pattern developed in vitro only in the presence of the aglycones of vicine (divicine) or convicine (isouramil) but not in the presence of the compounds themselves. The results of these studies demonstrate that vicine and convicine when injected intraperitoneally into the rat are converted to their aglycones which cause signs similar in many respects to those observed in the human metabolic disease, favism.     

Protection against the toxic effects of the favism factor (divicine) in rats by vitamins E,A and C and iron chelating agents

Five experiments were carried out with weanling Sprague-Dawley rats to determine if prior administration of either free-radical scavenging compounds (vitamins A, C and E) or chelating agents (EDTA and desferox- amine) affected the toxicity of divicine (DV). In all experiments, intraperitoneal (IP) injections of 250 mg g^?1 body weight of DV alone resulted in 100% mortalities within 24 h with most of the deaths occurring before 4 h. Death was accompanied by a rapid decrease in the concentration of glutathione (GSH) in the red blood cells (RBC) and the 576 nm/628 nm absorbance ratio of haemoglobin. The first experiment demonstrated that IP injections of different amounts of vitamin E, 1 h prior to DV injection, prevented the decrease in the haemoglobin absorbancy ratio and GSH concentration and greatly reduced mortalities. In rats that received 1000 IU of vitamin E kg^?1 body weight prior to DV injection, mortality was only 20%. The second experiment demonstrated that the optimal time for IP administration of vitamin E was 1 to 4 h prior to DV injection although some protection was obtained after 96 h. In contrast, the optimal time for intramuscular injections was 24 h prior to DV administration. A dosage of 250 or 500 IU of vitamin E kg^?1 body weight provided complete protection (zero mortalities) against the toxic effects of DV. In the third experiment, the addition of varying amounts of vitamin E to the diet resulted in a dose dependent mortality curve with no deaths occurring in rats fed diets containing the highest concentrations of vitamin E. The fourth experiment also demonstrated that vitamin A, vitamin C, EDTA and desferoxamine each protected rats to varying degrees against the toxic effets of DV. In the final experiment it appeared that the combined injections of a free-radical scavenging compound (vitamin E) and a metal chelator (desferoxamine) provide more protection than vitamin E alone. These results demonstrate for the first time in vivo that certain vitamins, especially vitamin E, and metal chelators can provide varying and in some cases 100% protection against the toxic effects DV.     

Removal of favism-inducing factors vicine and convicine and the associated effects on the protein content and digestibility of fababeans (Vicia faba L)†

Ingestion of fababeans is associated with precipitation of the haemolytic disease favism in certain glucose-6-phosphate dehydrogenase-deficient humans. Hence their incorporation into weaning foods has not yet been practised. Few, if any, attempts to detoxify fababeans have so far been made. The present investigation has evaluated the effects of a series of treatments designed for vicine and convicine extraction and hydrolysis followed by oxidation of their pyrimidine moieties (divicine and isouramil). The effects of seed germination and oxidative treatment by hydrogen peroxide have also been examined. Extracts of treated samples were assayed for residual vicine and convicine. Toxicity was monitored by the changes in vitro of reduced glutathione (GSH) of red blood cells (RBCs) from Sprague Dawley rats deliberately made deficient in glutathione reductase activity to mimic favism-susceptible human RBCs. Treatments of whole cotyledons resulted in recovery of 59–93% vicine and 50–70% convicine originally present in the seeds. Treatments of fababean powders, however, were capable of lowering the vicine content by 94–100% and convicine content by 100%. Germinated seeds showed a drop in vicine content of 86% and their hydrogen peroxide treatment 91–93%. Convicine was totally absent in germinated and oxidised seeds. The results of toxicity assays were concomitant with vicine and convicine analyses. Protein content of original fababean powders was well recovered (up to 94.00%) and its digestibility was almost complete (99.34%). © 1999 Society of Chemical Industry     

Hypolipidemic Effect of Bamboo Shoot Oil (P. pubescens) in Sprague–Dawley Rats

Abstract: Atherosclerosis and its related complications are the leading causes of death in the West and in many developed countries. This study aims to investigate the hypolipidemic effect of bamboo shoot oil (BSO) in Sprague–Dawley rats. A group of rats had induced hyperlipidemia, hypercholesterolemia, and fatty liver by being fed with a high-fat, high-cholesterol diet for 4 wk. The control group was administered 10 mL distilled water per kg body weight, while the other groups were, respectively, administered 250 mg beta-sitosterol, 250 mg BSO, 500 mg BSO, and 1000 mg BSO per kg body weight by oral gavage. The results demonstrated that BSO could significantly decrease the levels of total cholesterol, triacylglycerol, low-density lipoprotein-cholesterol, phytosterol, lipoprotein lipase, hepatic lipase, and atherogenic index in serum, and increase the levels of cholesterol in feces. It could also significantly decrease the level of relative liver weight and liver lipids. The pronounced hypolipidemic effects of BSO might be attributed to its ability to inhibit cholesterol absorption and increase cholesterol excretion. These results suggest that consuming BSO may provide benefits in managing hypercholesterolemia. Therefore, BSO may be a good candidate for development as a functional food and nutraceutical.     

牛磺酸对大鼠的减重降脂作用

目的:探讨牛磺酸饮水对高脂血症大鼠减重降脂的作用。方法:根据血清总胆固醇(TC)和体重将SD大鼠随机分为对照组、高脂模型组和牛磺酸(低、高)剂量组。对照组摄食普通饲料,其余三组摄食高脂饲料,牛磺酸组饮用牛磺酸水溶液。饲养12周后处死动物,检测血清TC、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、甘油三酯(TG)水平,血清谷胱甘肽过氧化物酶(GSH-PX)和超氧化物歧化酶(SOD)活力;粪便中总胆汁酸(TBA)含量;肝脏TC、TG、游离脂肪酸(FFA)、还原型谷胱甘肽(GSH)、肝糖原的含量和GSH-PX酶活力。结果:高剂量牛磺酸显著降低高脂饮食大鼠的体重,两个剂量牛磺酸都可以显著降低大鼠附睾脂肪垫指数;高剂量牛磺酸显著降低大鼠血清TC、LDL-C、肝脏FFA和肝糖原水平,两个剂量牛磺酸对肝脏TC和TG均无显著影响,但都可显著增加粪便TBA含量;两个剂量牛磺酸都可以显著升高大鼠血清GSH-PX和肝脏GSH-PX、还原型GSH。结论:牛磺酸主要通过促进胆固醇转化为胆汁酸,并随粪便排出、加强脂质代谢减少肝脏FFA堆积、提高机体抗氧化能力等途径发挥减重降脂功效,但其减重降脂机制还需深入研究。     

Bioavailability of Copper Bound to Dietary Fiber in Mice and Rats

The bioavailability of copper (Cu) was compared in mice or rats fed diets containing wheat bran-bound Cu and adequate Cu (unbound) or deficient Cu with cellulose or wheat bran. Cardiac and hepatic Cu content were comparable in mice fed bran-bound or adequate Cu and greater than mice fed deficient Cu. Cardiac Cu content was comparable in rats fed bran-bound Cu and adequate Cu and greater than rats fed deficient Cu. Hepatic Cu content, however, was less in rats fed bran-bound Cu than adequate Cu and greater in both than deficient Cu. Both rats and mice utilized dietary Cu bound to wheat bran, suggesting that mineral-fiber interactions may not decrease bioavailability when dietary mineral is adequate. Tissue Cu content in Cudeficiency was lower in animals fed wheat bran compared to cellulose, suggesting that the type of fiber may exacerbate effects of mineral deficiency.     

Consumption of an infant formula supplemented with long chain polyunsaturated fatty acids and iron metabolism in rats

This study examined the effects of an infant formula supplemented with long-chain polyunsaturated fatty acids (LCPUFA) on iron metabolism in rats. Three isocaloric diets were given to weaning rats during 28 days (150 g/kg fat): control diet (C), unsupplemented (F) and supplemented (FS) infant formula (as the only fat source) diets. Food intake and body weight evolution showed no significant differences between F and FS, but in both groups resulted lower compared to C. LCPUFA supplementation did not affect apparent iron absorption and retention nor the absorption and retention efficiencies, haemoglobin, serum iron, total iron binding capacity, haematocrit, liver and spleen iron. However, erythrocytic iron showed significant differences: FS>F>C. The results indicate that consumption of a diet containing an infant formula supplemented with LCPUFA does not affect iron metabolism in growing rats. Further studies based on the relationship between iron and lipid composition of erythrocytic membranes are required.     

Methionine restriction up‐regulates the expression of the pi class of glutathione S‐transferase partially via the extracellular signal‐regulated kinase‐activator protein‐1 signaling pathway initiated by glutathione depletion

Understanding the molecular events underlying gene regulation by amino acids has attracted increasing attention. Here, we explored whether the mechanism by which methionine restriction affects the expression of the π class of glutathione S‐transferase (GSTP) is related to oxidative stress initiated by glutathione (GSH) depletion. Rat primary hepatocytes were cultured in an L‐15‐based medium in the absence or presence of 200 μM L ‐buthionine sulfoximine (BSO) or in a methionine‐restricted L‐15 medium supplemented with 20 μM L ‐methionine up to 72 h. BSO and methionine restriction time‐dependently induced GSTP mRNA and protein expression in a similar pattern accompanied by a decrease in the cellular GSH level. The phosphorylation of extracellular signal‐regulated kinase (ERK), but not of c‐Jun NH₂‐terminal kinase and p38, was stimulated by methionine restriction and BSO. Electromobility gel shift assay showed that the DNA‐binding activity of nuclear activator protein‐1 (AP‐1) increased in cells exposed to methionine restriction or BSO. With the ERK inhibitor FR180204, AP‐1 activation and GSTP expression were abolished. Moreover, the induction of GSTP by methionine restriction and BSO was reversed by GSH monoethyl ester and N‐acetylcysteine. Our results suggest that methionine restriction up‐regulates GSTP gene expression, which appears to be initiated by the ERK‐AP‐1 signaling pathway through GSH depletion in rat hepatocytes.     

沙棘粉对大鼠肝脏脂质代谢及氧化应激的影响

本文研究了沙棘粉对高脂膳食大鼠肝脏脂质代谢及氧化应激的影响。将50只成年雄性Wistar大鼠按体重随机分为对照组、高脂模型组、沙棘低剂量、中剂量和高剂量组5个组。对照组给予基础饲料,其余各组给予高脂饲料饲养,同时每日分别用0.5 mg/g bw、2.5 mg/g bw和5 mg/g bw的沙棘粉匀浆液灌胃大鼠。4 W后处死动物,采集肝脏,分别测定肝脏脂质含量、脂代谢相关酶活性和氧化应激水平。结果表明,与高脂模型组比较,一定剂量的沙棘粉可降低肝脏总胆固醇(TC)和甘油三脂(TG)水平,提高高密度脂蛋白(HDL-C)水平;使肝脏组织肝脂酶(HL)和脂蛋白脂酶(LPL)活性增强;还原型谷胱甘肽(GSH)含量和总超氧化物歧化酶(T-SOD)活力提高,丙二醛(MDA)含量下降。说明沙棘粉可降低高脂膳食大鼠肝脏脂质水平,提高肝脏脂代谢酶活性,增强抗氧化能力,减缓肝细胞的脂质过氧化。     

Metabolism of vicine and convicine in rat tissues: absorption and excretion patterns and sites of hydrolysis

The objectives of this study were to determine whether dietary vicine and convicine were absorbed by rat tissue, and to determine their excretion patterns and/or sites of degradation. Orally administered vicine and convicine were excreted in relatively low amounts via the kidney and faeces. However, no vicine or convicine was detected in the blood, liver, kidney or muscle tissue of rats which had been fed these compounds. In-vitro studies demonstrated that vicine and convicine were not hydrolysed in liver, kidney, muscle, caecal wall or intestinal wall homogenates. In contrast, digesta samples from the large intestine and caeca were able to rapidly hydrolyse these compounds, with the concomitant formation of new compounds. Digesta from the stomach and small intestine promoted the slow hydrolysis of these compounds, as did fresh faecal samples. These results would suggest that vicine and convicine are absorbed by the rat in only limited amounts, are not hydrolysed by rat tissues, and are rapidly cleared from tissue via the kidney. The bulk of the dietary vicine and convicine are hydrolysed in the large intestine and caecum.     

高脂饮食诱导高脂血症大鼠及不同器官病理变化

通过高脂饮食建立高脂血症大鼠模型,观察高脂血症大鼠体内程序性死亡受体1(PD-1)的表达变化。将40只雄性SD大鼠分为2组,分别饲喂普通饲料和高脂饲料12周,计算大鼠的肝脏、脾脏和胰腺指数,测定大鼠全血血糖,检测大鼠血清中甘油三酯(TG)、总胆固醇(T-CHO)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)的含量,通过HE染色检测大鼠肝脏的病理变化,同时采用RT-q PCR检测PD-1 mRNA在大鼠肝脏、脾脏和胰腺组织内的表达变化。结果表明:高脂饲料组大鼠的肝脏、脾脏和胰腺指数显著高于普通饲料组;高脂饲料组大鼠的血糖显著升高;高脂饲料组大鼠血清中的TG、T-CHO、LDL-C的含量均显著高于普通饲料组,LDLC/HDL-C的比值也显著高于普通饲料组,高脂血症大鼠造模成功。HE染色显示高脂饲料组大鼠肝脏组织内均出现明显脂肪空泡。与普通饲料组相比,高脂饲料组大鼠肝脏、脾脏和胰腺组织内PD-1 mRNA的表达均显著降低,提示PD-1可能参与了高脂血症的发生和发展。     

8-HYDROXY-2'DEOXYGUANOSINE LEVELS AND ANTIOXIDANT STATUS IN RAT LIVER FED WITH OLIVE AND CORN OIL DIETS: EFFECT OF ASCORBIC ACID SUPPLEMENATION

DNA damage and antioxidants status were determined in liver of rat fed with olive and corn oil diets with and without ascorbic acid supplementation. In order to elucidate the role of fat intake, the study included a control and hyperlipidic diet. Liver antioxidant activities were significantly influenced by dietary fat and intake levels. In general, control groups fed with corn oil diets exhibited reduced liver antioxidant (SOD, catalase, and GSH-PX) and GSH levels compared with rats fed on olive oil diets. These activities were lower in rats consuming hyperlipidic diets relative to the control groups. Ascorbic acid supplementation resulted in a slight decrease of antioxidant activities both in the control and hyperlipidic diets with the exception of GSH that showed high levels in rats fed on an olive oil diet supplemented with ascorbic acid. The results of oxidative DNA damage as measured by the induction of 8-hydroxy deoxyguanosine (8-OHdG) clearly confirmed that corn diet (rich in polyunsaturated fatty acids) induced DNA damage in a dose- dependent manner. No induction of 8-OHdG was detected for the diet containing olive oil (monounsaturated diet). Ascorbic acid had no effect on rat fed on an olive oil diet. In contrast, for corn diets the ascorbic acid showed     

Food Deprivation Promotes Oxidative Imbalance in Rat Brain

ABSTRACT:  The present study was aimed to evaluate the effect of food deprivation in brain oxidative status of Wistar and Goto-Kakizaki (GK) rats. For this purpose, we evaluated several oxidative stress parameters: lipid peroxidation (thiobarbituric acid reactive substances [TBARS]) and protein oxidation markers, hydrogen peroxide (H₂O₂) levels, nonenzymatic (reduced [GSH] and oxidized glutathione [GSSG] and vitamin E) and enzymatic (glutathione peroxidase [GPx], glutathione reductase [GRed], and manganese superoxide dismutase [MnSOD]) antioxidant defenses. Four-mo-old Wistar and GK rats were divided into 2 groups. One group of each rat strain was maintained under normal diet and the other groups were maintained under 50% food deprivation during 2 mo. GK rats under normal diet presented lower levels of vitamin E and higher GRed activity and GSH/GSSG ratio when compared with Wistar control rats. In Wistar rats, food deprivation induced a significant decrease in vitamin E levels and a significant increase in GPx activity, H₂O₂ production, and TBARS formation in the presence of the prooxidant pair ADP/Fe²⁺. However, GK rats under food deprivation presented a significant decrease in vitamin E levels and GRed activity and a significant increase in H₂O₂ production when compared with GK under normal diet. In summary, our results indicate that food deprivation affects brain oxidative status, which could predispose brain cells to degeneration and death.     

Glucoraphanin does not reduce plasma homocysteine in rats with sufficient Se supply via the induction of liver ARE-regulated glutathione biosynthesis enzymes

Data from human and animal trials have revealed contradictory results regarding the influence of selenium (Se) status on homocysteine (HCys) metabolism. It was hypothesised that sufficient Se reduces the flux of HCys through the transsulphuration pathway by decreasing the expression of glutathione (GSH) synthesising enzymes. Glucoraphanin (GRA) is a potent inducer of genes regulated via an antioxidant response element (ARE), including those of GSH biosynthesis. We tested the hypothesis that GRA supplementation to rat diets lowers plasma HCys levels by increasing GSH synthesis. Therefore 96 weaned albino rats were assigned to 8 groups of 12 and fed diets containing four different Se levels (15, 50, 150 and 450 μg kg(diet)(-1)), either without GRA (groups: C15, C50, C150 and C450) or in combination with 700 μmol GRA kg(diet)(-1) (groups G15, G50, G150 and G450). Rats fed the low Se diets C15 and G15 showed an impressive decrease of plasma HCys. Se supplementation increased plasma HCys and lowered GSH significantly by reducing the expression of GSH biosynthesis enzymes. As new molecular targets explaining these results, we found a significant down-regulation of the hepatic GSH exporter MRP4 and an up-regulation of the HCys exporter Slco1a4. In contrast to our hypothesis, GRA feeding did not reduce plasma HCys levels in Se supplemented rats (G50, G150 and 450) through inducing GSH biosynthesis enzymes and MRP4, but reduced their mRNA in some cases to a higher extent than Se alone. We conclude: 1. That the long-term supplementation of moderate GRA doses reduces ARE-driven gene expression in the liver by increasing the intestinal barrier against oxidative stress. 2. That the up-regulation of ARE-regulated genes in the liver largely depends on GRA cleavage to free sulforaphane and glucose by plant-derived myrosinase or bacterial β-glucosidases. As a consequence, higher dietary GRA concentrations should be used in future experiments to test if GRA or sulforaphane can be established as HCys lowering compounds.     

REPRODUCTIVE POTENTIAL OF MALE RATS FED DIETARY ETHYLENE DIBROMIDE

Ethylene dibromide (EDB), a grain fumigant, has been assessed for its toxic effects when fed to growing albino rats at 50, 100, 250 and 500 ppm in the diet for 90 days. Weekly body weight gain showed no effect on growth. Organ weights were normal and no histopathological lesions were observed in the liver, kidney, lungs, brain, spleen, adrenal gland, and the testis. Activities of the serum enzymes, viz., GOT, GPT, LDH and alkaline phosphatase were not affected. EDB fed male rats when mated with normal female rats showed no impairment in their reproductive performance.     

The requirement of essential fatty acids for maintenance of normal periodontal tissues in the rat

Rats fed a high sugar diet deficient in essential fatty acids develop periodontal changes similar to those of periodontal disease. These changes can be prevented if the rats are injected with sufficient essential fatty acids to maintain normal growth and development of the animals. This evidence indicates that the role of essential fatty acids in maintaining normal periodontal tissue is a systemic one.     

Turnover and hydrolysis of vicine and convicine in avian tissues and digesta

The objectives of this study were to establish factors influencing the absorption, excretion and hydrolysis of vicine and convicine in chicks. Blood vicine, following the oral administration of a single dosage of vicine into the crop of young chicks, reached maximum concentrations within 3 h. It was nearly completely removed from the blood within 12 h and had a half-life of approximately 4.5 h. The accumulation and excretion patterns of vicine in the liver and kidney were similar to those of the blood except that the concentrations were much higher in these tissues, particularly the kidney. Bile also contained a very high concentration of vicine which tended to accumulate following the decline in other tissues. These results together with the appearance of vicine in the urine of colostomised birds suggest that vicine is excreted in the urine and bile. Convicine in contrast to vicine was not absorbed by the chick. In-vitro studies were carried out with tissue and digesta homogenates from the chick in order to establish the site(s) at which vicine and convicine were hydrolysed to their aglycone forms. The results demonstrated that neither vicine nor convicine were hydrolysed in the presence of liver, kidney, intestinal wall or caecal wall homogenates, digesta from the large intestine or by enzymes present in whole or ground fababeans. They were, however, slowly hydrolysed in the presence of 0.1N HCl at 37°C and very rapidly hydrolysed by digesta from the caeca. Antibiotic additions to the diets markedly reduced the in-vitro rate of hydrolysis of these compounds. The latter results suggest that vicine and convicine are hydrolysed by microorganisms in the caeca of the chick but are not hydrolysed by the micro-organisms in the gastrointestinal tract, by endogenous tissue enzymes or by enzymes present in fababeans and only minimally hydrolysed by the low pH of the stomach.     

Biochemical parameters of rats fed dietary fibre preparation from sugar beet

Groups of 15 male rats were fed ad libitum for 4 weeks with a standard diet containing 0, 2.5, 5.0 or 10.0% dietary fibre (DF) prepared from sugar beet. The highest food consumption was found in the group with 10% DF in the diet. Food efficiency was highest in the control group. Average body weight increased continuously in all groups without significant differences. Enrichment of the diet with the DF preparation did not substantially influence urinary parameters [pH, specific gravity, protein or activities of aspartate aminotransferase (ASAT), alanine aminopeptidase and alkaline phosphatase (AP)]. Haemoglobin concentration and haematocrit, mean corpuscular haemoglobin concentration and mean corpuscular volume as well as total numbers of erythrocytes, thrombocytes and leukocytes counts did not significantly differ between the groups. Lower counts of eosinophils and neutrophils were measured in rats fed DF-enriched diets. Serum parameters (urea-N, protein, glucose, triglycerides and activities of ASAT, alanine aminotransferase, AP and leucine aminopeptidase) did not differ between groups. As the amount of DF preparation in the diet increased, serum cholesterol was reduced in trend. Furthermore, no significant differences were found between the groups with respect to the organ weights of rats. In conclusion, important or critical dose-related differences in the determined parameters were not found. This sub-acute feeding study showed that no toxic effects were related to used doses of DF which was prepared from sugar beet.     

普洱茶提取物及其复合配方改善糖尿病大鼠的糖脂代谢紊乱

本文观察了普洱茶提取物、玉米须提取物、低聚果糖及其复合配方对糖尿病模型大鼠糖脂代谢及胰岛素敏感性的影响。80只健康成年雄性SD大鼠随机分为8组:正常对照组给予普通饲料,模型对照组、普洱茶组、低聚果糖组、玉米须组以及低、中、高剂量复合配方组给予高脂饲料,受试物组经口灌胃给予6种受试物4周后,腹腔注射链脲佐菌素造模,继续给予受试物至实验结束。实验前后分别进行葡萄糖耐量试验,实验结束后测定各项指标。与模型对照组比较,普洱茶组大鼠体重、血清甘油三酯、肝脏胆固醇、肝脏甘油三酯、腹壁脂肪含量、脏体比、胰岛素抵抗指数分别降低了14.87%、77.59%、40.18%、39.18%、63.06%、55.81%和79.88%,但血糖和葡萄糖耐量无明显变化;低聚果糖组大鼠腹壁脂肪重量、脏体比、胰岛素抵抗指数分别降低了30.99%、29.46%和57.09%;玉米须组大鼠仅肝脏甘油三酯降低了36.06%;而三者复合配方能够显著降低大鼠的体重、体脂、血脂和肝脂水平,有效改善糖脂代谢紊乱和胰岛素抵抗。