Fatty liver in dairy cows post partum is associated with decreased concentration of plasma triacylglycerols and decreased activity of lipoprotein lipase in adipocytes

Cholesterol and phospholipid concentrations in serum lipoproteins, plasma activities of lecithin:cholesterol acyltransferase (LCAT) and phospholipid transfer protein (PLTP) and lipoprotein lipase (LPL) activity in adipose tissue biopsies were measured ante and post partum in dairy cows given either free or restricted access to feed during the dry period. After parturition, all cows were fed ad libitum. The purpose of this study was to try to understand the earlier observed marked drop post partum in plasma triacylglycerol (TAG) in terms of lipoprotein metabolism in cows developing fatty liver post partum. As would be expected, free access to feed during the dry period induced a rise of hepatic TAG concentrations post partum associated with a decrease in plasma TAG levels. Total and free cholesterol concentrations in the VLDL, IDL, LDL and HDL2 fractions fell immediately after parturition. VLDL and IDL cholesterol concentrations remained at a constant, low level during the entire sampling period post partum, whereas the drop in LDL and HDL2 cholesterol post partum was followed by a rebound rise. Plasma LCAT and PLTP activities decreased by on average 19% and 33%, respectively, after parturition and then rose to values seen before parturition, but there was no effect of feeding regimen during the dry period. Activities of LCAT and PLTP were significantly correlated with cholesterol and phospholipid concentrations in LDL and HDL2. Plasma LCAT activity, as measured with exogenous substrate, and PLTP activity were both positively correlated with HDL3 phospholipid levels. LPL activity in adipose tissue dropped after parturition, the drop being smaller after feeding ad libitum during the dry period. It is concluded that the drop in adipose tissue LPL activity post partum is at variance with the simultaneous fall in plasma TAG. Possibly, the decrease in adipose tissue LPL activity helps to channel fatty acids away from adipose tissue into the udder. The post-partum changes in lipid transfer proteins in the blood are in line with the changes observed in the levels of the lipoproteins.     

Amelioration of cadmium-induced oxidative stress, impairment in lipids and plasma lipoproteins by the combined treatment with quercetin and α-tocopherol in rats

Cadmium (Cd) exposure results in numerous pathological consequences including oxidative stress and dyslipidemia. The present study was designed to investigate the efficacy of combined treatment with quercetin (QE) and α-tocopherol (AT) against Cd-induced oxidative stress and alterations in lipids and lipoproteins in the plasma and liver of rats. Oral administration of Cd (5 mg/kg bw/d) for 4 wk has shown a significant (P < 0.05) increase in thiobarbituric acid reactive substances (TBARS), lipid hydro peroxides (LOOH), total cholesterol, low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C), free fatty acids (FFA), phospholipids (PL), triglycerides (TGs), and the activity of hydroxyl-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase) in plasma with a significant (P > 0.05) reduction in the levels of reduced glutathione (GSH), high density lipoprotein cholesterol (HDL-C), and the activity of lecithin cholesterol acyl transferase (LCAT) in plasma. In addition, the levels of hepatic thiobarbituric acid reactive substances (TBARS), LOOH, conjugated dienes (CD), protein carbonyls (PC), and the activity of HMG-CoA reductase, levels of cholesterol, FFA, and TGs were significantly (P > 0.05) increased and the level of PL is significantly (P > 0.05) decreased along with the decreased activity of LCAT in the liver of Cd-treated rats. Oral supplementation with QE (50 mg/kg bw/d) and AT (50 mg/kg bw/d) for 4 wk in Cd intoxicated rats significantly (P > 0.05) has reduced the plasma levels of TBARS, LOOH, GSH, cholesterol, FFA, TGs, VLDL-C, LDL-C, and the activity of HMG-CoA and significantly (P > 0.05) has increased the activity of LCAT and the plasma levels of HDL-C. The oral supplementation also significantly (P > 0.05) has reduced the hepatic oxidative stress markers, cholesterol, TGs, FFA, and significantly (P > 0.05) has increased the LCAT activity and the PL in liver. Our results indicate that the combined treatment with QE and AT has normalized all the previously mentioned biochemical parameters in Cd-intoxicated rats than the individual treatments. The combined treatment has provided remarkable protection against Cd-induced oxidative stress and alterations in lipid metabolism and, thereby, reduced the Cd-mediated cardiovascular diseases.     

Hypolipidemic effect of proteoglycans isolated from sweet potato (Ipomoea batatas LAM) in hyperlipidemia rats

Effects of sweet potato proteoglycans (SPG) in rats fed high lipid diets were investigated. Serum lipid indices for SPG were evaluated. SPG had hypolipidemic effects that were correlated with dosage. There were no significant (p>0.05) differences in hypolipidemic effects between SPG varieties of different molecular weights. SPG-1 (Mw value: 508.3 kDa) significantly (p<0.05) reduced serum total cholesterol (TC), triacylglyceride (TAG), low density lipoprotein cholesterol (LDL-C), and apolipoprotein (Apo) B levels, and the arteriosclerosis index (AI), and induced serum high density lipoprotein cholesterol (HDL-C), ApoA-I, lecithin cholesterol acyltransferase (LCAT), and liver lipoprotein lipase (LPL) activities, compared with controls. The whole blood viscosity and red blood cell (RBC) membrane microviscosity were also decreased. Hypolipidemic effects were mediated via elevation of the serum HDL-C concentration by induction of LACT activity, an increased ApoA-I concentration, and a reduction in the serum lipid concentration due to regulation of LPL activity.     

Effects of cocoa extract containing polyphenols and methylxanthines on biochemical parameters of obese‐diabetic rats

BACKGROUND: Previous studies have indicated that cocoa extract possesses hypoglycaemic and hypocholesterolaemic properties in streptozotocin‐induced diabetic rats. However, there has been limited research on the effects of cocoa extract on obese‐diabetic (Ob‐db) rats that mimic human diabetes syndrome. Hence this study was initiated to determine the effect of cocoa extract containing polyphenols and methylxanthines on several biochemical parameters, namely glucose level, insulin sensitivity and lipid profiles of Ob‐db rats. RESULTS: Intake of cocoa extract supplemented with polyphenols (2.17 mg epicatechin, 1.52 mg catechin, 0.25 mg dimer and 0.13 mg trimer g^?1 cocoa extract) and methylxanthines (3.55 mg caffeine and 2.22 mg theobromine g^?1 cocoa extract) for 4 weeks significantly (P < 0.05) reduced the plasma total cholesterol, triglycerides and low‐density lipoprotein cholesterol of obese‐diabetic rats (Ob‐db + cocoa) compared with non‐supplemented animals (Ob‐db). Short‐term (acute) supplementation of cocoa extract significantly (P < 0.05) reduced the plasma glucose level at 60 and 90 min compared with untreated rats as assessed by the oral glucose tolerance test. However, no significant differences were observed in plasma glucose level, insulin level and insulin sensitivity after chronic (4 weeks) cocoa extract supplementation. CONCLUSION: The results of this study suggest that cocoa extract possesses hypocholesterolaemic properties and can exert a transient glucose‐lowering effect but not long‐term glucose control. Copyright © 2008 Society of Chemical Industry     

Antihyperlipidemic effect of diosmin: A citrus flavonoid on lipid metabolism in experimental diabetic rats

The present study was hypothesized to evaluated the antihyperlipidemic effect of diosmin (DS) on lipid metabolism in experimental diabetic rats. Diabetes was induced male albino Wistar rats by intraperitoneal administration of streptozotocin (STZ) (45 mg/kg b.w.) 15 min after the ip administration of nicotinamide (NA) (110 mg/kg b.w.). DS were administered to diabetic rats intragastrically at 100 mg/kg b.w. for 45 days. The levels of plasma and tissue lipids (cholesterol, triglycerides) (TGs), free fatty acids (FFAs) and phospholipids (PLs), low density, very low-density lipoproteins (LDL and VLDL), and high-density-cholesterol (HDL-C) were measured. The activities of 3-hydroxy 3-methylglutaryl coenzyme A (HMG-CoA) reductase, lipoprotein lipase (LPL) and lecithin cholesterol acyl transferase (LCAT) were assayed. The levels of plasma and tissue lipids decreased with significant increase in HDL-C levels. The altered activities of lipid metabolic enzymes were restored to near normal. The present findings suggest that DS can potentially ameliorate lipid abnormalities in experimental diabetes.     

熟化发芽糙米粉对高脂血症大鼠的作用研究

该文主要研究瞬时熟化(双螺杆挤压)后的发芽糙米粉对高血脂模型SD大鼠的影响。将高血脂SD大鼠模型随机分为5组,分别为高脂组(high fat diet group,HFD)、高、中、低剂量组(饲料中分别含有12.5%、25%、50%的熟化发芽糙米粉),每组12只;药物组[HFL:HFD+立普妥,10 mg/(kg·d)],并设立正常空白组。饲喂7周后,腹主动脉采血测定生化指标。剂量组与高脂组相比,肝脏/体重的脏体比有不同程度的降低,低剂量组较高脂组显著降低0.58(P<0.05),同药物组相比差异不显著。剂量组与高脂组相比可显著降低大鼠的血清总胆固醇(total cholesterol,TC)、甘油三酯(triglyceride,TG)、低密度脂蛋白胆固醇(low-density lipoprotein cholesterol,LDL-C)水平,与药物组之间差异不显著。熟化发芽糙米粉对高血脂模型的SD大鼠具有一定的降血脂作用。同时熟化发芽糙米能显著增强超氧化物歧化酶(superoxide dismutase,SOD)活性,低剂量组较高脂组SOD浓度增高23.72 U/mL(P<0.05),从而增强机体自由基清除能力,显著增强过氧化氢酶(catalase,CAT)(P<0.05)与SOD协同作用而清除氧自由基,增强机体谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活性,减少过氧化对机体的伤害。     

Lipid-lowering action of pectin from Cucumis sativus

The oral administration of the pectin extracted from the fruit of Cucumis sativus at a dose of 5 g kg⁻¹ body weight day⁻¹ showed significant hypolipidemic action in normal as well as cholesterol-fed experimental animals. Concentrations of cholesterol, triglycerides, phospholipids and free fatty acids were found to be significantly reduced in the serum and tissues of experimental animals. Activity of HMG CoA reductase was found to be enhanced. Pectin administration decreased the activities of glucose-6-phosphate dehydrogenase and malate dehydrogenase while it increased the activities of lipoprotein lipase and plasma LCAT. Incorporation of labelled ¹⁴C acetate into free cholesterol was significantly higher in the liver of pectin-treated rats. Concentrations of bile acids (hepatic and fecal) and fecal neutral sterols showed significant increases in the pectin-administered groups.     

The probiotic role of Lactobacillus plantarum in reducing risks associated with cardiovascular disease

A novel strain of Lactobacillus plantarum DMDL 9010 (CGMCC No. 5172) was isolated from naturally fermented mustard. The potential cholesterol reduction effects of this strain were investigated using an in vivo model. The results showed that L. plantarum DMDL 9010 at a dose of 10⁹ cells per day significantly reduced (P ≤ 0.05) serum total cholesterol (TC), low‐density lipoprotein cholesterol content (LDL‐C) levels and atherosclerosis index (AI) by 23.03%, 28.00% and 34.03%, respectively, while L. plantarum DMDL 9010 did not exhibit a significant effect on reducing serum triglycerides (TG) and increasing the serum high‐density lipoprotein cholesterol content (HDL‐C) in experimental rats (P > 0.05). The morphological and pathological changes in the liver illustrated that L. plantarum DMDL 9010 protected the rats against hepatocyte steatosis. Additionally, a high dose of L. plantarum DMDL 9010 was shown to exhibit a positive cholesterol‐lowering effect through decreasing the liver cholesterol (?33.20%) and triglyceride (?40.86%) levels, and increasing significantly (P ≤ 0.05) faecal cholesterol (+31.07%) and bile acid excretion (+70.18%). The results demonstrated that L. plantarum DMDL 9010 acted in a dose‐dependent way to decrease serum and total hepatic cholesterol and triglyceride and enhance faecal excretion of bile acids. In conclusion, these findings suggest that L. plantarum DMDL 9010 has potential to be explored as a probiotic for hypercholesterolaemic preventive and therapeutic.     

Hypocholesterolemic Effects of Capsaicinoids and Lactobacillus plantarum Swun5815 Combined by Inhibiting Cholesterol Synthesis and Increasing Bile Acid and Sterols Excretion on Ovariectomized Rats

This study evaluated the hypocholesterolemic effects and potential metabolism of single and combined administrations of capsaicinoids and Lactobacillus plantarum SWUN5815 in ovariectomized rats. Forty female Sprague–Dawley rats were divided into 5 treatment groups. One group was sham‐operated (with 1 mL/100 g BW physiological saline), and the 4 other groups were double‐ovariectomized: OVX–CON (with 1 mL/100 g BW physiological saline), OVX–CAP (with 1 mL/100 g BW physiological saline and fed with food containing 0.08 g/kg capsaicinoids), OVX–L. P. (with 1 mL 2 × 10⁹ cfu/mL/100 g BW L. plantarum SWUN5815), and OVX–CAP + L. P. (with 1 mL 2 × 10⁹ cfu/mL/100 g BW L. plantarum SWUN5815 and fed with food containing 0.08 g/kg capsaicinoids). Rats were sacrificed after 6 weeks of feeding. Results showed that the combination of capsaicinoids and L. plantarum significantly decreased the total cholesterol, triglyceride and low‐density lipoprotein cholesterol of plasma, total cholesterol and lipid accumulation of liver in ovariectomized rats without affecting food intake. Bile acid contents in the fecal excrement and small intestines were significantly increased by the combination compared with the individual effects. However, the mRNA levels of 3‐hydroxy‐3‐methylglutaryl coenzyme A reductase (HMG‐CoA R), farnesoid X receptor (FXR), ileum bile acid binding protein (IBABP), and apical sodium‐dependent bile acids transporter (ASBT) significantly decreased. Liver X receptor also remarkably increased. Therefore, these genes potentially affect cholesterol metabolism by inhibiting cholesterol synthesis and promoting excretion of bile acid. The protective effects of the combination of capsaicinoids and L. plantarum SWUN5815 on the intestines were significant in ovariectomized rats.     

Effect of various dietary fats and proteins on serum cholesterol level in rats

A 60 day experiment on growing rats was performed to evaluate the effect of two protein sources (casein and soybean protein isolate) and four fats (olive oil, OO; evening primrose oil, EO; linseed oil, LO; and butter, B) on plasma lipoprotein fractions: total cholesterol (TC), high‐density lipoprotein cholesterol (HDL‐C), low‐density lipoprotein cholesterol (LDL‐C) and triacylglycerol (TAG) levels. The different protein and fat sources had no influence on body weight gain of rats. Fats had no significant effect on TC and LDL‐C. Significant differences were found only in HDL‐C. OO gave the lowest (43.3 mg dl^?1) and EO the highest (54.4 mg dl^?1) value. Proteins had a significant influence on all lipids analysed. Soybean protein caused higher TC (78.5 vs 67.9 mg dl^?1), HDL‐C and TAG levels but significantly lowered LDL‐C in the plasma of rats. These results suggest that protein has a stronger effect on cholesterol level than fat. © 2002 Society of Chemical Industry     

Effects of highly purified sardine proteins on lipid peroxidation and reverse cholesterol transport in rats fed a cholesterol-rich diet

The effect of highly purified sardine proteins was compared with that of casein on serum and lipoproteins lipid peroxidation and reverse cholesterol transport. Lecithin:cholesterol acyltransferase (LCAT) activity, high density lipoproteins (HDL₂ and HDL₃) composition and serum lipid and lipoproteins peroxidation were determined in rats fed a cholesterol-rich diet. Hypercholesterolemic rats were divided into two groups fed diets enriched with cholesterol and containing 20% of highly purified sardine proteins (SPc) or casein (CASc) for 28 days. A control group was fed a standard diet (CAS). Compared with CAS and CASc, the thiobarbituric acid reactive substances (TBARS) concentrations of low density lipoprotein (LDL)–HDL₁ in SPc were 3.5- and 1.7-fold higher compared with casein diets. TBARS in HDL₂ and HDL₃ were, respectively, 2.3- and 1.6-fold lower in SPc compared with CASc. In SPc group, LCAT activity was higher compared to CASc and CAS (P < 0.05). Purified sardine proteins had no beneficial effects on LDL-cholesterol and lipid peroxidation. However, they reduced HDL oxidation and improved reverse cholesterol transport, in the hypercholesterolemic rat.     

Hypolipidaemic and hypoglycaemic effects of total flavonoids from seed residues of Hippophae rhamnoides L. in mice fed a high-fat diet

BACKGROUND: The present study was designed to investigate the hypolipidaemic and hypoglycaemic effects of total flavonoids from seed residues of Hippophae rhamnoides L. (FSH) in a high‐fat diet fed mouse model. Consumption of a high‐fat diet (HFD) for 4 weeks caused a significant rise of serum total cholesterol in mice. These hypercholesterolaemic mice then were orally administrated with different doses of FSH (50, 100 and 150 mg kg^?1 body weight) and simvastatin (20 mg kg^?1 body weight) for another 12 weeks under continuous HFD feeding. RESULTS: FSH administration markedly reduced total mouse body, liver, and epididymal fat pad weights. Serum total cholesterol and low density of lipoprotein‐cholesterol levels were also significantly decreased by FSH treatment. Additionally, FSH significantly lowered total cholesterol and triglyceride concentrations in liver, and the results were corroborated by transmission electron microscope findings. The rise in serum glucose was significantly suppressed by FSH treatment while improving impaired glucose tolerance. CONCLUSION: These results suggest that FSH possesses hypolipidaemic and hypoglycaemic properties in mice fed a high‐fat diet and could be developed as a supplement in healthcare foods and drugs. Copyright © 2011 Society of Chemical Industry     

THE EFFECTS OF SOYBEAN PROTEIN-DERIVED HYDROLYSATE ON LIPID METABOLISM IN RATS FED A HIGH CHOLESTEROL DIET

This study was performed to investigate the effects of the peptic undigested fraction derived from soybean protein hydrolysate (UDSP) on lipid metabolism in rats fed a cholesterol‐enriched diet (1%). Eighteen male Wistar rats‐weighing 205–235 g were randomly divided into three groups: the control group (20% casein), U2 (18% casein + 2% UDSP), and U5 group (15% casein + 5% UDSP). After 4 weeks, rats were sacrificed, and the lipid profiles of the plasma, liver, and feces were determined. Body weight gain, daily food intake, and liver weight showed no differences among the groups, but the feeding efficiency ratio in the U5 group was significantly lower than that in the other groups (P < 0.05). There were no changes in plasma cholesterol, LDL‐C, HDL‐C, and liver cholesterol levels in each group. However, the U5 group showed a significantly lower VLDL‐C compared to the control and U2 groups. In addition, the plasma and liver TG content were lower in the U2 and U5 groups than in the control group (P < 0.05). Moreover, the fecal bile acid and total neutral steroid excretions were higher in the U2 and U5 groups (P < 0.05) compared to the control group.     

Inhibitory effects of Hibiscus sabdariffa L extract on low‐density lipoprotein oxidation and anti‐hyperlipidemia in fructose‐fed and cholesterol‐fed rats

Hibiscus sabdariffa L extract (HSE) is an aqueous extract of Hibiscus sabdariffa L flowers that is used as a local soft drink and medical herb in Taiwan. Oxidation of low‐density lipoprotein (LDL) has been shown to increase the incidence of atherosclerosis. In this study, we determined the antioxidative activity of HSE on LDL oxidation by examining relative electrophoretic mobilities (REM) and thiobarbituric acid‐reactive substances (TBARS). The data revealed an inhibitory effect of HSE on Cu²⁺‐mediated REM and TBARS. HSE exhibited a remarkable ability to reduce cholesterol degradation and ApoB fragmentation. Overall, HSE showed a high potency to inhibit the production of oxidized LDL induced by copper and, specifically, to reduce serum triglycerides in high‐fructose diet (HFD) fed rats and serum cholesterol in high‐cholesterol diet (HCD) fed animals. The levels of LDL and the ratio of LDL‐cholesterol (LDL‐C) to HDL‐cholesterol (HDL‐C) were reduced by HSE in both hyperlipidaemia models. Based on these findings, we suggest that HSE may be used to inhibit LDL oxidation and to prevent various types of hyperlipidaemia in HFD‐ or HCD‐fed rats. Copyright © 2004 Society of Chemical Industry     

Effects of defatted dried roselle (Hibiscus sabdariffa L.) seed powder on lipid profiles of hypercholesterolemia rats

BACKGROUND: In vivo investigations were made of the effect of defatted dried roselle seed powder (DRS) on the lipid profiles of rats with induced hypercholesterolemia. The two‐batch sample consisted of 23 and 20 Sprague‐Dawley male rats randomly divided into four groups and fed with four different diets. The first batch of rats was fed with normal, hypercholesterol, hypercholesterol + 10 g kg^?1 (w/w) DRS and hypercholesterol + 20 g kg^?1 (w/w) DRS diets. The second batch of rats was fed with normal, hypercholesterol, hypercholesterol + 50 g kg^?1 (w/w) DRS and hypercholesterol + 150 g kg^?1 (w/w) DRS diets. Treatments were given for a total of 5 weeks. RESULTS: Results indicated that the addition of 10 g kg^?1 and 20 g kg^?1 of DRS did not significantly lower the plasma total cholesterol (TC) levels. In contrast, 50 g kg^?1 and 150g kg^?1 DRS significantly lowered (P < 0.05) the TC and low density lipoprotein cholesterol (LDL‐C) levels. CONCLUSION: The addition of 50 g kg^?1 and 150 g kg^?1 DRS showed potential hypocholesterolemic effects. Furthermore, these findings indicated that protein, lipid and dietary fibre were high in the seed powder. Copyright © 2008 Society of Chemical Industry     

Hypocholesterolemic Action of Fermented Brown Rice Supplement in Cholesterol-Fed Rats: Cholesterol-lowering Action of Fermented Brown Rice

Fermented rice products have been implicated in vascular injury and atherosclerosis in recent animal and human studies. In the current study, whether consumption of differently processed brown rice diets may change the cholesterol metabolism was evaluated in male Spraque Dawley (SD) rats after 28 d of treatment with diets containing 1% cholesterol. The experimental diets include corn starch alone as control diet (CO) or a diet containing a 50% substitute of CO; uncooked brown rice (UB), cooked brown rice (CB), lactic acid bacteria (LAB), brown rice mixed with LAB (BLAB), and fermented‐brown rice by LAB (FB), respectively. Among them, FB group elicited significantly lower levels of plasma and hepatic triglycerides, plasma total cholesterol, low‐density lipoprotein cholesterol (LDL‐C), and very low‐density lipoprotein cholesterol (VLDL‐C) by 33% to 50%, whereas higher levels of HDL‐C were elicited by 227% compared with the CO group (P < 0.05). These amelioration action on lipid profile in FB group appeared to correspondent to the higher excretions of fecal weight, triglyceride (TG), total cholesterol (TC), and bile acid (P < 0.05). Furthermore, sensory properties such as flavor liking, taste liking, and overall acceptability of the diet were significantly improved by the addition of fermented brown rice. Conclusively, fermented‐brown rice may have a potent cholesterol‐lowering benefits with sensory quality improvement of the diet.     

Dietary effects on growth,liver peroxides,and serum and lipoprotein lipids in rats fed a thermoxidised and polymerised sunflower oil

The effect on food intake, weight gain, liver lipid peroxides, lipemia and lipoprotein composition was determined in rats fed a diet with 15% sunflower oil used repeatedly for frying and containing ∽19% polar material (group 2). These dietary effects were compared over a 4 week study period with those found in rats fed a control diet that contained 15% unused sunflower oil with ∽5% polar material (group 1). Both groups had similar food and nutrient intakes (except for linoleic acid, significantly lower (P<0·01) in group 2), yet the final weight gain and food efficiency and protein efficiency ratios were significantly lower in group 2. As a consequence of thermoxidised oil ingestion, liver homogenates from group 2 presented higher (P<0·02) levels of thiobarbituric acid reactive substances (TBARS) Liver TBARS levels were significantly correlated (P<0·01) with the amount of thermoxidised substances ingested. No treatment effect was found on VLDL lipid composition. However, the LDL fraction of group 2 animals appears enriched (P<0·05) in total and free cholesterol. In group 2 rats, phospholipids, and total and esterified cholesterol were significantly increased (P<0·05) in HDL. As a consequence of the changes in the lipoprotein composition, the amount of all forms of serum cholesterol, and serum phospholipids was significantly higher (at least P<0·05) while the amount of serum triacylglycerols remained unchanged in rats fed the used oil. HDL-phospholipids were significantly correlated (P<0·02) with the amount of thermoxidised compounds ingested. The increase in serum cholesterol and phospholipids, and in HDL-cholesterol and HDL-phospholipid concentration seens in group 2 rats may be a protective mechanism against the peroxidative stress produced by the ingestion of used sunflower oil. © 1998 SCI.     

碱提醇沉黑木耳多糖体外和体内降血脂功能

目的:探讨黑木耳多糖体内和体外降血脂功能。方法:采用离体实验模拟人体胃和肠道的p H值环境,探讨不同溶剂提取黑木耳多糖及其不同醇沉片段对胆酸盐的结合能力,评价其体外降血脂功能。以高脂饲料喂养小鼠建立高血脂模型,通过黑木耳多糖的治疗,比较治疗前后小鼠体质量、血清总胆固醇(total cholesterol,TC)、总甘油三酯(triglyceride,TG)、低密度总胆固醇(low density lipoprotein cholesterol,LDL-C)、高密度总胆固醇(high density lipoprotein cholesterol,HDL-C)含量及其关键酶卵磷脂胆固醇酰基转移酶(lecithin cholesterol acyltransferase,LCAT)、肝脂酶(liver lipase,HL)和脂蛋白脂酶(lipoprotein lipase,LPL)的活性,研究碱提黑木耳多糖对高血脂模型小鼠的降血脂作用。结果:体外降血脂实验结果表明:3种不同的黑木耳多糖样品中,碱提黑木耳多糖的结合效果最好;不同体积分数乙醇醇沉黑木耳多糖片段的结合效果比较显示,70%醇沉片段结合胆酸盐效果最好。体内降血脂实验结果发现,碱提+70%醇沉黑木耳多糖能够缓解小鼠体质量的增长,显著缓解TC、TG和LDL-C含量的下降,显著提升HDL-C水平,控制LCAT含量、HL和LPL活性的降低。结论:碱提+70%醇沉黑木耳多糖具有降血脂功能。     

Dietetic and hypocholesterolaemic action of black soy peptide in dietary obese rats

To investigate the effect of peptides from black soy (rat's eye) bean (Rhynchosia volubilis Lour.) on weight gain and lipid composition, Sprague–Dawley male rats were fed either a black soy peptide (BSP; 2, 6 or 10% of energy)‐containing diet or a casein control diet (20% of energy) enriched with 36% fat and 1% cholesterol for 28 days. Compared with the casein group, the BSP groups showed significant attenuation of body, liver and epididymal adipose tissue weight gains (P < 0.05). Moreover, rats that consumed BSP had a lower total cholesterol concentration and low‐density lipoprotein/high‐density lipoprotein (LDL/HDL) ratio in serum and a lower level of hepatic triglycerides as well as higher excretion of faeces compared with those fed only casein (P < 0.05). Molecular weights of peptides from black soy were mainly below 10 kDa, and Arg/Lys and Gly/Met ratios in BSP were five and three times of those in casein respectively. It is concluded that BSP can be a potent nutraceutical component for anti‐obesity and hypolipidaemic benefits. Copyright © 2007 Society of Chemical Industry