Hypocholesterolemic effects of phenolic-rich extracts of Chemlali olive cultivar in rats fed a cholesterol-rich diet

This study was designed to test the lipid-lowering and the antioxidative activities of green and black olive phenolic extracts. Wistar rats fed a standard laboratory diet or a cholesterol-rich diet for 16 weeks were used. The serum lipid levels, the malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) as well as that of catalase (CAT) were examined. The cholesterol-rich diet induced hypercholesterolemia that was manifested in the elevation of total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C). Administration of aqueous methanol and ethyl acetate extracts of green olives and ethyl acetate extract of black olives significantly lowered the serum levels of TC and LDL-C, while increasing the serum level of high density lipoprotein cholesterol (HDL-C). Furthermore, the content of MDA in liver, heart and kidney decreased significantly after oral administration of green and black olive extracts compared with those of rats fed a cholesterol-rich diet. In addition, olive extracts increased CAT and SOD activities in liver. These results suggested that the hypocholesterolemic effect of green and black olive extracts might be due to their abilities to lower serum cholesterol level as well as to slow down the lipid peroxidation process and to enhance the antioxidant enzyme activity.     

Effect of dietary substitution of groundnut oil on blood glucose, lipid profile, and redox status in streptozotocin-diabetic rats

The effect of groundnut oil on blood glucose, lipid profile, lipid peroxidation, and antioxidant status in streptozotocin-diabetic rats was investigated and compared with diabetic and drug-treated rats. Diabetes was induced in adult female Wistar rats by intraperitoneal administration of streptozotocin (40 mg/kg b-wt). Normal and diabetic rats were fed an oil-free diet containing 2 percent oil supplemented with groundnut oil (6g per 94g diet), to give 8 percent oil content, for 42 days. Diabetic rats had elevated levels of glucose (322.61 ± 9.49), glycosylated hemoglobin (HbA_1c), vitamin E, thiobarbituric acid reactive substances (TBARS), and lipid hydroperoxides (HP) and decreased levels of hemoglobin (Hb), vitamin C, and reduced glutathione (GSH). An increase in the activities of glucose-6-phosphatase and fructose-1,6-bisphosphatase and a decrease in hexokinase activity also were observed in the liver and kidney. When diabetic rats were fed groundnut oil, a significant reduction in glucose (244.04 ± 11.66), HbA_1c, TBARS, HP levels, and glucose-6-phosphatase and fructose-1,6-bisphosphatase activities and an elevation in Hb, vitamin E, GSH levels, and hexokinase activity were observed. Diabetic rats had elevated total cholesterol (TC), VLDL-cholesterol, LDL-cholesterol, and triglycerides (TG) and decreased HDL-cholesterol. Diabetic rats fed groundnut oil showed a small but significant reduction in TC, VLDL-C, LDL-C, and TG and an elevation in HDL-C. Groundnut oil consumption slightly but significantly decreases the blood glucose, HbA_1c, lipid peroxidation, and lipid profile and increases antioxidant levels in diabetic rats.     

参麦注射液对高脂血症大鼠血脂的调节作用

目的：通过观察参麦注射液对高脂血症模型大鼠的血脂水平和一系列相关生化指标的影响,探讨其对高脂血症模型大鼠血脂的调节作用。方法：30只SPF级雄性SD大鼠用基础饲料适应性喂养1周,随机分为3组（n=10）：对照组,模型对照组,参麦注射液组。对照组用基础饲料喂养,模型对照组和参麦注射液组用高脂饲料喂养,每周测定动物体重一次。参麦注射液组每天给予2次参麦注射液10 ml/kg,连续灌胃45 d。之后测定大鼠血清总胆固醇（TC）、甘油三酯（TG）、高密度脂蛋白（HDL-C）、低密度脂蛋白（LDL-C）、超氧化物歧化酶（SOD）、谷胱甘肽过氧物酶（GSH-Px）、丙二醛（MDA）、脂蛋白酯酶（LPL）和肝酯酶（HL）活性。结果：模型对照组大鼠体重、血清中TC、TG、LDL-C和MDA水平较对照组明显升高（P<0.01）,而HDL-C、SOD、GSH-Px、LPL和HL水平明显降低（P<0.01）。参麦注射液组大鼠体重、血清中TC、TG、LDL-C和MDA水平较模型对照组明显降低（P<0.01）,而HDL-C、SOD、GSH-Px、LPL和HL水平明显升高（P<0.05,P<0.01）。结论：参麦注射液对高脂模型大鼠的血脂具有较明显的调节作用,并具有抗脂质过氧化的作用。     

Single intravenous injection of plasmid DNA encoding human paraoxonase-1 inhibits hyperlipidemia in rats

Paraoxonase-1 (PON1, EC 3.1.8.1) is a high-density lipoprotein (HDL)-associated antioxidant enzyme, and its activity correlates negatively with the level of plasma low-density lipoprotein cholesterol (LDL-C) and triglyceridemia (TG). In this study, we examined the therapeutic effect of plasmid DNA containing the human PON1 gene (pcDNA/PON1) in hyperlipidemic model rats. The rats were fed a high-fat and high-cholesterol diet for 25 days to produce a hyperlipidemic animal model. Single intravenous injection of pcDNA/PON1 into model rats prevented dyslipidemia and hepatic lipid accumulation. The mechanisms of pcDNA/PON1 in treating hyperlipidemia were associated with increases of serum antioxidant PON1 and SOD activities, and with reduction of the levels of total cholesterol (TC), LDL-C and TG. The results suggest the potential therapeutic effect of pcDNA/PON1 on hyperlipidemia.     

Comparison of regulative functions between dietary soy isoflavones aglycone and glucoside on lipid metabolism in rats fed cholesterol

The effects of dietary soy isoflavones aglycone and glucoside on lipid metabolism were compared in male Sprague-Dawley rats (4 weeks old) given purified diets containing 0.3% cholesterol. The rats were fed a diet supplemented with either isoflavone aglycone-rich powder (IF-A group) or isoflavone glucoside-rich powder (IF-G group) or isoflavone-free diet (control group) for 40 days. The additional level of isoflavone aglycone moiety in the diet was prepared to the same level (approximately 0.096 g/100 g: approximately 0.1% in diet). The activity of hepatic cholesterol 7alpha-hydroxylase tended to be slightly higher in the rats fed isoflavones than in those fed the isoflavone-free diet. On the other hand, the activity of hepatic Delta6 desaturase in the IF-A group was lower than that of the control group. Reflecting this effect, the Delta6 desaturation indices [(20:3n-6+20:4n-6)/18:2n-6] in liver phospholipids of the IF-A group were lower than those in the control group. Liver and serum total cholesterol levels and liver TG level were also reduced by consumption of isoflavone aglycone. Moreover, serum TG level was lowered by consumption of both isoflavones aglycone and glucoside. The level of serum total isoflavones in the IF-A group was significantly higher than that in the IF-G group. Therefore, we speculate that the absorption speed of isoflavone aglycones might be faster than that of isoflavone glucosides in rats. This study suggests that dietary soy isoflavones, particularly their aglycone form, may exert a beneficial effect on lipid metabolism in rats fed cholesterol.     

Oleuropein supplementation increases urinary noradrenaline and testicular testosterone levels and decreases plasma corticosterone level in rats fed high-protein diet

The effects of oleuropein, a phenolic compound in extra virgin olive oil, on protein metabolism were investigated by measuring testicular testosterone and plasma corticosterone levels in rats fed diets with different protein levels. In Experiment 1, rats were fed experimental diets with different protein levels (40, 25 and 10 g/100 g casein) with or without 0.1 g/100 g oleuropein. After 28 days of feeding, the testosterone level in the testis was significantly higher and the plasma corticosterone level was significantly lower in rats fed the 40% casein diet with oleuropein than in those fed the same diet without oleuropein. The urinary noradrenaline level, nitrogen balance and hepatic arginase activity were significantly higher in rats fed the 40% casein diet with oleuropein supplementation than in those fed the 40% casein diet without oleuropein supplementation. In Experiment 2, the effects of oleuropein aglycone (a major phenolic compound in extra virgin olive oil and the absorbed form of oleuropein ingested in the gastrointestinal tracts) on the secretion of luteinizing hormone (LH) from the pituitary gland, which regulates testosterone production in the testis, were investigated in anesthetized rats. Plasma LH level increased dose dependently after the administration of oleuropein aglycone (P<.001, r= 0.691). These findings suggest that dietary supplementation with 0.1 g/100 g oleuropein alters the levels of hormones associated with protein anabolism by increasing urinary noradrenaline and testicular testosterone levels and decreasing plasma corticosterone level in rats fed a high-protein diet.     

Antioxidant and hypolipidaemic properties of red seaweed,Gracilaria changii

The edible red seaweed, Gracilaria changii, was collected from the coastal area of Sarawak, Malaysia, and evaluated for its hypolipidaemic properties using high cholesterol/high fat (HF) induced male Sprague–Dawley rats. In the in vivo study, the HF diet group showed significantly higher total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), atherogenic index (AI) and body weight gain as compared to other treatment groups. At the end of treatment period, rats fed with a HF diet supplemented with 5 % freeze-dried G. changii powder had significantly reduced plasma TC (?39.19 %), LDL-C (?36.36 %), and triglycerides (TG) content (? 25.45 %). Meanwhile, 10 % seaweed powder significantly lowered the plasma TC, LDL-C and TG content by ?40.34, ?35.95 and ?30.91 % respectively, compared to the HF group. The AI of rats supplemented with 10 % seaweed powder was the lowest among the treatment groups and indicates a lowered risk for cardiovascular diseases. The plasma lipid peroxidation of the seaweed powder-fed groups was also significantly lower than the HF group, while the erythrocyte enzyme antioxidant activities of superoxide dismutase, catalase and glutathione peroxidase of the treatment groups were also improved. Diets supplemented with seaweed powder also decreased plasma aspartate aminotransferase and the alanine aminotransferase levels.     

Effect of Curcuma kwangsiensis polysaccharides on blood lipid profiles and oxidative stress in high-fat rats

We have investigated the protective effect of polysaccharides from Curcuma kwangsiensis (CKP) against oxidative injury in rats fed high-fat diet. The protective effect of CKP was compared with Lovastatin, a well-known antioxidant. Sixty SD rats were used for the experimental study. Oxidative injury was induced by feeding high-fat diet for 3 weeks. The blood profiles, total cholesterol (TC), triacylglycerol (TG), low-density lipoprotein cholesterol (LDL-c) levels during experimental period were significantly increased in untreated model control group, whereas high-density lipoprotein cholesterol (HDL-c) levels and antioxidant enzymes activities significantly decreased in untreated model control group. The levels of TC, TG, LDL-c levels in CKP-treated rats were decreased significantly when compared to the untreated model control group, which were brought down to near normal in CKP-treated group. HDL-c level and antioxidant enzymes activities were found to be significantly increased in serum of CKP-treated group compared to the untreated model control group. The protective effect of CKP against oxidative injury was comparable to that of Lovastatin. Our data suggest that CKP exerts its protective effect by modulating the extent of lipid peroxidation and augmenting antioxidant defense system and thus protects the experimental animals against oxidative injury induced by high-fat diet treatment.     

脂负荷性饵食对家兔脂代谢的影响

目的探讨建立兔饵食性高脂血症模型的方法,观察高脂饮食对兔体重、死亡率及血脂变化情况。方法取普通级雄性新西兰大耳白兔,其中随机抽取10只作为普通饮食组,喂以普通饮食;其他动物给予高脂饮食,4周后,根据血清TC水平分为高脂饮食敏感组和高脂饮食非敏感组,继续喂养9周,观察三组间兔血清总胆固醇（TC）、甘油三脂（TG）、高密度脂蛋白胆固醇（HDL-C）和低密度脂蛋白胆固醇（LDL-C）的变化。结果与普通饮食组相比,高脂饮食敏感组在第4～13周时血清TC、TG、HDL-C、LDL-C水平显著升高（P〈0.01）,高脂饮食非敏感组在第7～13周时,动物血清TC、HDL-C、LDL-C水平显著升高（P〈0.01）,而高脂饮食非敏感组血清TG水平的改变无统计学意义（P〉0.05）。与高脂饮食敏感组相比,高脂饮食非敏感组家兔血清TC、TG、HDL-C和LDL-C水平的上升程度均显著低于高脂饮食敏感组动物（P〈0.01）。结论首次发现兔对高脂饮食敏感性存在差异,高脂饮食非敏感组家兔抗病能力、对环境的适应能力和耐受性均高于高脂饮食敏感组兔。与高脂饮食敏感组家兔相比,高脂饮食非敏感组家兔对高脂饮食耐受性强。     

Effects of different dietary regimes alone or in combination with standardized Aronia melanocarpa extract supplementation on lipid and fatty acids profiles in rats

This study investigated different dietary strategies, high-fat (HFd), or standard diet (Sd) alone or in combination with standardized Aronia melanocarpa extract (SAE), as a polyphenol-rich diet, and their effects on lipids and fatty acids (FA) in rats with metabolic syndrome (MetS). Wistar albino rats were randomly divided into two groups: healthy and rats with MetS, and then depending on dietary patterns on six groups: healthy rats fed with Sd, healthy rats fed with Sd and SAE, rats with MetS fed with HFd, rats with MetS fed with HFd and SAE, rats with MetS fed with Sd, and rats with MetS fed with Sd and SAE. 4 weeks later, after an overnight fast (12–14 h), blood for determination of total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), index of lipid peroxidation (measured as TBARS), and FA was collected. Increased FA and lipid concentration found in MetS rats were reduced when changing dietary habits from HFd to Sd with or without SAE consumption. Consumption of SAE slightly affects the FA profiles, mostly palmitoleic acid in healthy rats and PUFA in MetS?+?HFd rats. Nevertheless, in a high-fat diet, SAE supplementation significantly decreases n-6/n-3 ratio, thereby decreasing systemic inflammation. Further researches are warranted to confirm these effects in humans.

     

Synergistic action of olive oil supplementation and dietary restriction on serum lipids and cardiac antioxidant defences

Caloric intake is higher than recommended in many populations. Therefore, enhancing olive oil intake alone may not be the most effective way to prevent cardiovascular diseases. The purpose of the present study was to analyse the association of olive oil and dietary restriction on lipid profile and myocardial antioxidant defences. Male Wistar rats (180-200 g, n = 6) were divided into 4 groups: control ad libitum diet (C), 50% restricted diet (DR), fed ad libitum and supplemented with olive oil (3 mL/(kg x day)) (OO), and 50% restricted diet and supplemented with olive oil (DROO). After 30 days of treatments, OO, DR, and DROO groups had increased total cholesterol and high-density lipoprotein cholesterol concentrations. DR and DROO animals showed decreased low-density lipoprotein cholesterol. DROO had the lowest low-density lipoprotein cholesterol concentration. Total lipids and triacylglycerols were raised by dietary restriction and diminished by olive oil. OO rats had higher myocardial superoxide dismutase and lower catalase and glutathione peroxidase activities than C rats. DR and DROO showed enhanced cardiac superoxide dismutase, catalase, and glutathione peroxidase activities from the control. Olive oil supplementation alone improved the lipid profile but was more effective when coupled with dietary restriction. There was a synergistic beneficial action of dietary restriction and olive oil on serum lipids and myocardial antioxidant defences.     

Nasturtium officinale reduces oxidative stress and enhances antioxidant capacity in hypercholesterolaemic rats

Nasturtium officinale R. Br. (Brassicaceae) has been used as a home remedy by the people of south eastern (SE) region of Iran as a medicinal plant. This therapeutical application has been attributed to Nasturtium officinale (N. officinale) antioxidant capacity which is mostly tested by means of cell-free assays: 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP). In addition, the antioxidant effect of N. officinale extract has been investigated in hypercholesterolaemic rats in vivo. The results revealed that the extract has notable scavenging activity against DPPH radicals as well as potent reducing power in FRAP assay. Intragastric administration of N. officinale (500 mg/kg body weight per day) to groups of hypercholesterolaemic rats for 30 days lowered their blood total cholesterol (TC), triglyceride (TG), and low density lipoprotein cholesterol (LDL-C) levels by 37, 44 and 48%, respectively. However, the blood high density lipoprotein cholesterol (HDL-C) levels in the same treated rats increased by 16%. To evaluate the mechanism(s) of action, we studied the antioxidative potential of N. officinale extract in terms of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione reductase (GR) activities and also the level of reduced glutathione (GSH) in the liver tissues. In addition, hepatic tissue malondialdehyde level (MDA, an index of lipid peroxidation) was also determined. Under hypercholesterolaemic condition, hepatic MDA was increased. Moreover, our data indicated GSH depletion along with significant reduction in the activities of CAT and SOD in rats fed high-fat diet rats. On the other hand, significant elevation in the activities of GPx and GR were seen in the same group of rats. Treatment of hypercholesterolaemic rats with N. officinale extract significantly increased the GSH level along with enhanced CAT and SOD activities in liver tissues. Furthermore, N. officinale extract significantly decreased hepatic MDA as well as GPx and GR activities in plant-treated rats. Based on our data, it can be concluded that N. officinale has a high hypolipidaemic activity and this may be attributed to its antioxidative potential.     

金耳菌丝体多糖对实验性2型糖尿病大鼠的降血糖作用研究

本文研究了金耳菌丝体多糖(TMP)对实验性2型糖尿病大鼠血糖、血脂、胰岛素敏感性和抗氧化能力的影响。采用烟酰胺,链脲佐菌素和高脂饲料诱导2型糖尿病大鼠模型,以50和100mg/(kg.d)剂量的TMP连续灌胃48d,监测血糖,测定血清胰岛素、体重、脂代谢及抗氧化系统部分相关指标,并进行口服糖耐量实验。结果显示,TMP可明显降低2型糖尿病大鼠的血清葡萄糖、总胆固醇、甘油三酯和丙二醛水平,并极显著提高受试模型鼠的胰岛素敏感指数,血清超氧化物歧化酶活性和肝脏过氧化氢酶活性。此外,TMP能显著降低糖耐量实验中糖负荷后120min时糖尿病大鼠的血糖含量。上述结果表明TMP可有效降低实验性2型糖尿病大鼠的血糖水平,纠正脂代谢紊乱,改善胰岛素抵抗,增强抗氧化能力。     

Supplementation of naringenin and its synthetic derivative alters antioxidant enzyme activities of erythrocyte and liver in high cholesterol-fed rats

The antioxidative effects of naringenin (1) and its synthetic derivative, naringenin 7-O-cetyl ether (2), were tested. Male rats were fed a 1 g/100 g high-cholesterol diet for 6 weeks with supplements of either 1 or 2 (0.073 mmol/100 g diet) to study the effects on the antioxidant enzyme activities in the erythrocyte and liver. The erythrocyte catalase (CAT) and superoxide dismutase (SOD) activities were significantly higher in the compounds 1 or 2 supplemented groups than in the control group, whereas the hepatic SOD and CAT activities were significantly lower in the compound 2 supplemented group. The compounds 1 and 2 supplements to a high cholesterol diet lowered or tended to lower the plasma TBARS levels, that is, lipid peroxide products, while enhancing the plasma paraoxonase activity. These results indicate that the supplementation of 1 and 2 was effective in improving the antioxidant capacity of the erythrocyte and liver, plus the synthetic functional compound 2 appeared to be as potent as 1 in enhancing the antioxidant defense system.     

A comparative study on hypolipidemic activities of high and low molecular weight chitosan in rats

The hypolipidemic activities of high (712.6kDa) and low (39.8kDa) molecular weight chitosan (HMWC and LMWC) were evaluated in rats fed high-fat diets. Thirty-two male Sprague-Dawley rats in four groups were fed on three high-fat diets with each of them containing HMWC, LMWC or cellulose (high-fat control), and a control normal-fat diet for eight weeks. Compared with HMWC group, LMWC group showed decreased body weight gain, serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C), as well as decreased liver triglyceride (TG). Fecal fat and cholesterol of LMWC group was lower than those of HMWC group. However, the activities of liver and serum lipoprotein lipase (LPL) of LMWC group were increased compared with HMWC group. The obtained results suggested that hypolipidemic activity of LMWC was better than HMWC, which might be partially attributed to the increase of serum and liver LPL activities.     

菊苣提取物和菊粉降脂活性研究

以300日龄商品代尼克T粉壳蛋鸡为试验动物,研究了菊苣提取物和菊粉对血清脂质、蛋黄总脂和胆固醇的影响.结果显示,0.1%菊苣提取物组、2.0%菊苣提取物组和0.1%菊粉组血清胆固醇(TC)、甘油三脂(TG)、低密度脂蛋白(LDL-C)均显著低于对照组(P<0.05),其中0.1%菊苣提取物组TC降低36.47%,TG降低40.71%,LDL-C降低36.09%,0.1%菊粉组LDL-C降低16.23%,差异极显著(P<0.01);2.0%菊苣提取物组高密度脂蛋白(HDL-C)比对照组高23.19%,差异极显著(P<0.01);2.0%菊苣提取物组蛋黄总脂和蛋黄胆固醇显著降低(P<0.05).表明菊苣提取物和菊粉均具有降血脂活性,但菊苣提取物比菊粉活性更强;菊苣提取物还具有降低蛋黄总脂和胆固醇的作用.     

Protective effects of diosgenin in the hyperlipidemic rat model and in human vascular endothelial cells against hydrogen peroxide-induced apoptosis

Hyperlipidemia is a major cause of atherosclerosis and atherosclerosis-associated conditions in cardiovascular diseases. Oxidative stress, as a main risk factor causes vascular endothelial cell apoptosis, which is implicated in the pathogenesis of cardiovascular disorders. Diosgenin, an aglycone of steroidal saponins, has been reported to exert anti-proliferative and proapoptotic actions on cancer cells widely. In this study, we propose that diosgenin can protect the hyperlipidemic rats and prevent endothelial apoptosis under oxidative stress. We investigated the hypolipidemic and antioxidative effects of diosgenin on rats fed with high cholesterol and high fat diet for 6 weeks. Serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), glutathione peroxidase (GSH-PX), nitric oxide synthase (NOS), hepatic malondialdehyde (MDA), lipoprotein lipase (LPL), hepaticlipase (HL) and superoxide dismutase (SOD) activities were evaluated. Then we explored the effects and mechanism of diosgenin against hydrogen peroxide-induced apoptosis of human vein endothelium cells (HUVECs). Intracellular reactive oxygen species (ROS), glutathione (GSH), nitric oxide (NO), DNA fragment formation and mitochondrial membrane potentials (ΔΨm) were determined. Diosgenin treatment increased LPL, HL, SOD, GSH-PX and NOS activities, thus attenuated oxygen free radicals, decreased MDA, TC, TG and LDL-C levels in hyperlipidemic rats. Diosgenin pretreatment significantly attenuated H₂O₂-induced apoptosis in HUVECs, intracellular ROS, GSH depletion, DNA fragment formation, and restored NO, ΔΨm. These results suggested that diosgenin is a very useful compound to control hyperlipidemia by both improving the lipid profile and modulating oxidative stress and prevent H₂O₂-induced apoptosis of HUVECs, in partly through regulating mitochondrial dysfunction pathway.     

有氧运动联合黑果枸杞对高脂膳食大鼠心肌脂代谢某些指标的影响

目的:研究有氧运动联合黑果枸杞对高脂膳食大鼠心肌脂代谢某些指标的影响。方法:55只雄性Wistar大鼠经过适应性饲养4 d后进行20 min/d的无负重游泳训练,连续3 d,筛选淘汰5只不适应游泳训练的大鼠后,按体重以数字随机分组法分为5组:普通膳食+安静组(RDC组)、高脂膳食+安静组(HDC组)、高脂膳食+黑果枸杞+安静组(HDLC组)、高脂膳食+有氧运动组(HDM组)、高脂膳食+黑果枸杞+有氧运动组(HDLM),每组10只。HDM组和HDLM组进行6周每周6次60 min/d的无负重游泳训练。RDC组大鼠以普通饲料常规喂养;其余各组以高脂饲料喂养; HDLC组和HDLM组大鼠灌胃黑果枸杞,灌胃剂量为4.48 g/(kg·d),灌胃体积为5 ml/kg,其余各组灌胃等量蒸馏水。6周后,测定大鼠Lee’s指数,取血、心肌检测相关生化指标。结果:与RDC组比较,HDC组Lee’s指数,血清FFA、TNF-α、IL-6、TC、TG、LDL-C,心肌FFA、ICAM-1显著升高(P<0.01);血清HDL-C水平显著降低(P<0.01)。与HDC组比较,HDLC、HDM、HDL...     

Efficient Method for the Preparation of Escherichia coli Polynucleotide Phosphorylase Suitable for the Synthesis of Polynucleotides

The effects of astilbin in Kohki tea, which is produced from the leaves of Engelhardtia chrysolepis Hance (Chinese name, huang-qui), and of an aglycone of astilbin, taxifolin, on the serum and liver lipid concentrations, and on the erythrocyte and liver antioxidative enzyme activities were determined with rats fed on a cholesterol-free diet. The total liver cholesterol concentration tended to be decreased by feeding with astilbin, and significantly decreased by feeding with taxifolin. The liver phospholipid concentration was decreased by feeding with both astilbin and taxifolin. In addition, astilbin and taxifolin lowered the serum and liver TBARS concentrations, but did not influence the serum and liver antioxidative enzyme activities, suggesting the possibility that these compounds acted to lower the TBARS concentration by their direct antioxidative action in vivo, almost without influencing the antioxidative enzyme activities.     

Oleuropein prevents ethanol-induced gastric ulcers via elevation of antioxidant enzyme activities in rats

Purified oleuropein from olive leaf extract has been shown to have antioxidant effects in our recent studies. Thus, the aim of this study was to assess the antioxidant abilities of oleuropein in comparison with ranitidine in ethanol-induced gastric damages via evaluation of ulcer index inhibition, antioxidant enzyme activities, and lipid peroxidation level. Fifty-six adult male Sprague?CDawley rats were divided into seven equal groups as follows: control group, ethanol group (absolute ethanol 1?ml/rat), oleuropein group (12?mg/kg), and oleuropein (6, 12, and 18?mg/kg) plus ethanol groups, as well as ranitidine (50?mg/kg) plus ethanol group. Pretreatment with oleuropein (12 and 18?mg/kg) significantly increased the ulcer index inhibition (percent), in comparison with oleuropein (6?mg/kg). Glutathione peroxidase (GPx) activity was significantly lower in the ethanol group when compared with the other groups whereas, treatment of rats with oleuropein (12?mg/kg) significantly increased glutathione content in gastric tissue when compared with the other groups, and lipid peroxidation was significantly reduced in the oleuropein- (12 and 18?mg/kg) and ranitidine-treated animals. Superoxide dismutase (SOD) and catalase (CAT) activities were both much higher in oleuropein-treated rats than the ethanol group, and although there was a moderate increase in SOD and CAT activities in ranitidine-treated rats, the differences were not significant. These findings suggest that oleuropein has beneficial antioxidant properties against ethanol-induced gastric damages in the rat. Therefore, it seems that a combination regimen including both antioxidant and antisecretory drugs may be beneficial in prevention of ethanol-mediated gastric mucosal damages.