不同剂量鹅油对小鼠血脂代谢及抗氧化能力的影响

以昆明种小鼠为研究对象,研究了不同剂量的鹅油对小鼠血脂代谢及抗氧化能力的影响。结果表明:①与猪油组相比,低剂量鹅油组小鼠体重极显著性降低(P<0.01),中剂量鹅油组显著性降低(P<0.05),而高剂量鹅油组无显著性变化(P>0.05)。②与猪油组相比,低、中剂量鹅油组血浆总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)均有极显著性差异,低剂量鹅油组低密度脂蛋白胆固醇(LDL-C)的含量极显著性降低,中剂量鹅油组LDL-C的含量显著性降低,高剂量鹅油组TC、TG、HDL-C均有显著性差异,LDL-C有极显著性差异。③与猪油组相比,低、中剂量鹅油组血浆和肝脏中总抗氧化力(T-AOC)、超氧化物歧化酶(SOD)、谷胱甘肽氧化物酶(GSH-Px)极显著性升高,丙二醛(MDA)含量极显著性降低;高剂量鹅油组T-AOC、SOD、GSH-Px显著性升高,MDA显著性降低;低剂量鹅油组血浆和肝脏中过氧化氢酶(CAT)极显著性升高,中剂量鹅油组血浆和肝脏中CAT显著性升高;高剂量鹅油组血浆中CAT显著性升高,而肝脏中无显著性变化。④与猪油组相比,低、中、高剂量鹅油组血浆中肝脂酶(HL)显著性升高,脂蛋白脂肪酶(LPL)无显著性变化,中、低剂量鹅油组总脂酶显著性升高,而在高剂量鹅油组无显著性变化;中、低剂量鹅油组肝脏中HL、LPL和总脂酶极显著性升高;高剂量鹅油组HL、LPL和总脂酶显著性升高。⑤与猪油组相比,中、低剂量鹅油组动脉粥样硬化指数(AI)极显著性降低,高剂量鹅油组显著性降低。表明富含单不饱和脂肪酸鹅油能够调节小鼠血脂代谢,具有提高小鼠体内抗氧化和抗动脉粥样硬化功能。     

Effects of albusin B (a bacteriocin) of Ruminococcus albus 7 expressed by yeast on growth performance and intestinal absorption of broiler chickens--its potential role as an alternative to feed antibiotics

BACKGROUND: Bacteriocins with antimicrobial activity are considered as potential alternatives to antibiotics. The aim of this study was to investigate the effect of albusin B (bacteriocin) of Ruminococcus albus 7 expressed by yeast on the growth performance of broiler chickens. Ninety 1‐day‐old healthy broiler chickens were randomly divided into three groups: control, albusin B (2.5 g kg^?1) and nosiheptide (2.5 mg kg^?1, antibiotic control). Growth performance and intestinal functions were measured at 5 weeks of age. RESULTS: Albusin B‐supplemented broilers showed increased body weight gain compared with control broilers (54.7 ± 5.3 vs 48.5 ± 6.1 g day^?1 per bird, P < 0.05). Broilers supplemented with nosiheptide had a less developed mucosal layer than broilers in the other two groups. Compared with the control group, broilers supplemented with albusin B or nosiheptide showed increased mRNA expression of sGLT1, GLUT2 and PEPT1 in the jejunum (P < 0.05). The faecal Lactobacillus count was higher in the albusin B group than in the other two groups (P < 0.05). CONCLUSION: Albusin B supplementation increased intestinal absorption and elevated the faecal Lactobacillus count, thereby promoting the growth performance of broiler chickens. These improvements resulting from albusin B supplementation provide evidence of potential alternatives to antibiotics in broiler chicken feed. Copyright © 2011 Society of Chemical Industry     

低聚壳聚糖对生长育肥猪抗氧化性能、脂类代谢和肌肉品质的影响

研究低聚壳聚糖对生长育肥猪抗氧化性能、脂类代谢和肌肉品质的影响。结果表明:与对照组相比,低聚壳聚糖组可显著提高血清总抗氧化能力,其中40mg/kg低聚壳聚糖组达到极显著水平(P<0.01);对血清过氧化氢酶活性、丙二醛浓度和谷胱甘肽过氧化物酶活性无显著影响(P>0.05);可降低血清中总胆固醇、高密度脂蛋白胆固醇和低密度脂蛋白胆固醇的含量,但差异均不显著(P>0.05);20mg/kg低聚壳聚糖能显著提高宰后眼肌L*45min(P<0.05),显著降低眼肌a*45min和a*24h(P<0.05),40mg/kg低聚壳聚糖也能显著降低眼肌a*24h(P<0.05),但两者对眼肌熟肉率、蒸煮损失、失水率、滴水损失和pH值无显著影响(P>0.05)。低聚壳聚糖以40mg/kg添加量较好。     

Oyster hydrolysate ameliorates ethanol diet-induced alcoholic fatty liver by regulating lipid metabolism in rats

We evaluated the effect of oyster hydrolysate, which was prepared using transglutaminase, protamex and neutrase (TGPN), on alcoholic fatty liver. Sprague–Dawley rats were fed a diet containing 5% (v/v) ethanol or an isocaloric amount of dextrin–maltose for 6 weeks and orally administered TGPN or silymarin for another 4 weeks. TGPN significantly decreased the liver index (liver weight/body weight), serum and hepatic lipid levels and increased the serum adiponectin level. Based on histological analysis, TGPN reduced the number of lipid droplets and lipid accumulation in liver tissue. TGPN enhanced the expression of AMP-activated protein kinase and activated its downstream pathway which controls lipid metabolism. Additionally, TGPN decreased the levels of liver function markers (aspartate aminotransferase and alanine aminotransferase) and tumour necrosis factor alpha. Consequently, TGPN ameliorated alcoholic fatty liver by inhibiting fatty acid and cholesterol synthesis, promoting fatty acid oxidation and decreasing liver cell damage.     

Cannabinoid-1 receptor activation modulates lipid mobilization and adipogenesis in the adipose tissue of dairy cows

Amplified adipose tissue (AT) lipolysis and suppressed lipogenesis characterize the periparturient period of dairy cows. The intensity of lipolysis recedes with the progression of lactation; however, when lipolysis is excessive and prolonged, disease risk is exacerbated and productivity compromised. Interventions that minimize lipolysis while maintaining adequate supply of energy and enhancing lipogenesis may improve periparturient cows' health and lactation performance. Cannabinoid-1 receptor (CB1R) activation in rodent AT enhances the lipogenic and adipogenic capacity of adipocytes, yet the effects in dairy cow AT remain unknown. Using a synthetic CB1R agonist and an antagonist, we determined the effects of CB1R stimulation on lipolysis, lipogenesis, and adipogenesis in the AT of dairy cows. Adipose tissue explants were collected from healthy, nonlactating and nongestating (NLNG; n = 6) or periparturient (n = 12) cows at 1 wk before parturition and at 2 and 3 wk postpartum (PP1 and PP2, respectively). Explants were treated with the β-adrenergic agonist isoproterenol (1 μM) in the presence of the CB1R agonist arachidonyl-2′-chloroethylamide (ACEA) ± the CB1R antagonist rimonabant (RIM). Lipolysis was quantified based on glycerol release. We found that ACEA reduced lipolysis in NLNG cows; however, it did not exhibit a direct effect on AT lipolysis in periparturient cows. Inhibition of CB1R with RIM in postpartum cow AT did not alter lipolysis. To evaluate adipogenesis and lipogenesis, preadipocytes isolated from NLNG cows' AT were induced to differentiate in the presence or absence of ACEA ± RIM for 4 and 12 d. Live cell imaging, lipid accumulation, and expressions of key adipogenic and lipogenic markers were assessed. Preadipocytes treated with ACEA had higher adipogenesis, whereas ACEA+RIM reduced it. Adipocytes treated with ACEA and RIM for 12 d exhibited enhanced lipogenesis compared with untreated cells (control). Lipid content was reduced in ACEA+RIM but not with RIM alone. Collectively, our results support that lipolysis may be reduced by CB1R stimulation in NLNG cows but not in periparturient cows. In addition, our findings demonstrate that adipogenesis and lipogenesis are enhanced by activation of CB1R in the AT of NLNG dairy cows. In summary, we provide initial evidence which supports that the sensitivity of the AT endocannabinoid system to endocannabinoids, and its ability to modulate AT lipolysis, adipogenesis, and lipogenesis, vary based on dairy cows' lactation stage.     

Absorption and tissue distribution of dietary quercetin and quercetin glycosides of apple skin in broiler chickens

BACKGROUND: Apple skins are a rich source of flavonols, in particular quercetin (Q) glycosides. The objective of the present study was to investigate the presence of Q metabolites in plasma, various tissues, and excreta when the commercial broiler chicken's diet was supplemented with Q (0, 50, 150, 300, or 600 mg kg^?1 body weight per day), an apple skin extract (ASE; 50, 150 mg total phenolics kg^?1 body weight per day), or a dried apple skin powder (ASP; 50 mg total phenolics kg^?1 body weight per day). RESULTS: When Q was supplemented for 3 days, Q sulfate, Q glucuronide, Q glucoside glucuronide, Q glucoside sulfate, and isorhamnetin glucoside were detected by liquid chromatography–tandem mass spectrometry in the liver and duodenum. Deconjugated Q was also detected in the breast and thigh tissues of ASE‐ and ASP‐supplemented broilers. Regardless of the source or concentration of Q, the antioxidant capacity measured by ferric reducing ability of plasma (FRAP) assay in the plasma and tissues of the broilers did not change significantly. CONCLUSIONS: As far as is known, this is the first report to demonstrate that Q and its glycosides can be absorbed and metabolized by broiler chickens. Copyright © 2010 Society of Chemical Industry     

Effect of flaxseed oil fortified with vitamin e and phytosterols on antioxidant defense capacities and lipids profile in rats

The main proposal of this study was to evaluate in vivo whether flaxseed oils fortified with micronutrients would have beneficial effects on lipid profile and antioxidant status in high-fat fed rats. Male Wistar rats were fed synthetic diets containing 10% of flaxseed oil (FO), phytosterols (PS) fortified FO (PS-FO), vitamin E (V(E) ) fortified FO (V(E) -FO), V(E) , and PS fortified FO (V(E) -PS-FO), respectively, for 4 wk. The results showed that V(E) fortified FO enhanced the enzymatic (SOD and GPX) and nonenzymatic (GSH and V(E)) antioxidant system, lowered the lipid peroxide (TBARS) concentration compared with FO (P < 0.05). And FO fortified with PS significantly reduced the plasma TG, TC and LDL-C levels, and hepatic TG and TC levels of rats compared with FO (P < 0.05), but had no significant effect on antioxidant defense capacities. Combined addition of V(E) and PS in FO had a synergetic effect. These results indicated that flaxseed oils fortified micronutrients V(E) and PS may contribute to reduce the risk factors of cardiovascular disease (CVD) by improving plasma antioxidant defenses and lipids profiles. PRACTICAL APPLICATION: Flaxseed oil usually contains greater than 50% of alpha-linolenic acid (ALA) and is a desire origin for n-3 PUFA. But consuming high dose of n-3 PUFA could lead to oxidative damage through free radical-chain reaction in cellular and subcellular membranes. Our studies showed that a regular intake of V(E) and PS fortified flaxseed oils increased antioxidant defenses and ameliorated lipids profile in high-fat fed rats, and these indicated that the flaxseed oil fortified with these micronutrients might reduce the incidence of CVD.     

Effects of trypsin inhibitor on plasma antioxidant activity and lipid levels in mice from sweet potato roots

BACKGROUND: Several inflammatory diseases are thought to be related to oxidative injury and reactive oxygen species have been proposed as important causative agents of heart disease and ageing. This study was designed to investigate the effects of sweet potato trypsin inhibitor (SPTI) on antioxidant enzymes, lipid peroxidation and lipid profiles in mice. RESULTS: Twenty mice were randomly divided into four groups and fed with TI (10, 50 and 100 mg kg^?1 BW) as treatment and with saline as a control in addition to regular diets. After 35 days, Trolox equivalent antioxidant capacity (TEAC), triglyceride (TG) and cholesterol levels in plasma and superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx), thiobarbituric acid reactive substances (TBARS) in liver were measured. Serum from the group that had received the the highest oral dose of SPTI (100 mg kg^?1 BW) had the highest total antioxidant activity (expressed as 3.59 ± 0.237 mmol L^?1 TEAC). The SOD, catalase and GPx activity of SPTI groups were significantly increased compared with the control group. Malondialdehyde (MDA) was significantly lower in all experimental groups compared with the control one. No significant differences in the concentration of low‐density lipoprotein (LDL)‐cholesterol was found, but high density lipoprotein (HDL)‐cholesterol, triglyceride (TG) and total cholesterol tended to decrease. CONCLUSION: This study showed that the oral intake of SPTI in mice may trigger inflammatory responses which result in an increase in antioxidant enzyme activities, and a decrease in MDA, TG and total cholesterol, which are known risk factors of inflammatory and heart disease. Copyright © 2008 Society of Chemical Industry     

共轭亚油酸对乳腺脂类代谢和乳腺发育的作用及其机理

共轭亚油酸(Conjugated Linoleic Acid,CLA)是亚油酸具有共轭双键的一组同分异构体,由瘤胃细菌在生物氢化过程中合成,具有抗癌、抗炎症、抗动脉粥样硬化等多种生物学功能。CLA在代谢方面也有调节作用,能影响全身代谢,影响肝脏、乳腺以及富含脂肪的相关组织代谢。在此介绍了CLA的来源、结构、对动物乳腺脂类代谢和乳腺发育的作用及其机理。     

茶多酚对apoE-/-小鼠脂类代谢和肠道双歧杆菌的影响

研究茶多酚对小鼠脂类代谢和结肠双歧杆菌的影响,探讨茶多酚采食与脂类代谢和肠道双歧杆菌之间的关系。ApoE-/-小鼠以高脂饲料饲养并在饮水中添加1.6g/L茶多酚,8周后用变性梯度凝胶电泳(DGGE)分析肠道双歧杆菌多样性。结果表明,高脂饮食对照组(HF)和茶多酚组(T)肠道双歧杆菌多样性有显著差异;16周后,T组血清中TC、LDL-C含量分别为19.8,16.1mmol/L,显著低于HF组的36.4,28.4mmol/L(P<0.05)。说明茶多酚采食对apoE-/-小鼠肠道双歧杆菌菌群多样性和脂类代谢均有显著的影响。     

Nutritional and physiological effects of rapeseed meal sinapine in broiler chickens and its metabolism in the digestive tract

Research was completed to investigate the impact of dietary rapeseed meal (RSM) sinapine (SNP) on broiler chickens. The control treatment was based on a corn/soybean meal diet, as were six additional treatments which contained three levels of SNP bisulphate or semi‐purified SNP in the form of an ethanol extract concentrate. The last three treatments were corn‐based but soybean meal was replaced by graded levels of RSM at 15, 22.5 and 30% of the diet and thereby added SNP in its native form. SNP bisulphate and SNP ethanol extract did not affect feed intake and performance of broiler chickens. SNP bisulphate increased diet AME (apparent metabolisable energy) (P < 0.01) while SNP ethanol extract increased diet AME and faecal protein digestibility (P < 0.01 and 0.05 respectively) in comparison with the control diet. Dietary treatment caused minor effects on tissue measurements. All the diets containing SNP reduced the empty weight of caeca (P < 0.05 or 0.01), suggesting that the hind gut might be an important metabolic site for SNP. The ileal digestibility of SNP was 35–42, 27–38 and 30–46% for SNP bisulphate, SNP ethanol extract and RSM SNP respectively, while faecal digestibility values were 68–72, 65–75 and 54–63% for the same treatment groups. A major metabolic pathway of SNP via hydrolysis into sinapic acid and choline in the digestive tract was identified. Copyright © 2003 Society of Chemical Industry     

Liver fat content and lipid metabolism in dairy cows during early lactation and during a mid-lactation feed restriction

During the transition period, the lipid metabolism of dairy cows is markedly affected by energy status. Fatty liver is one of the main health disorders after parturition. The aim of this study was to evaluate the effects of a negative energy balance (NEB) at 2 stages in lactation [NEB at the onset of lactation postpartum (p.p.) and a deliberately induced NEB by feed restriction near 100 d in milk] on liver triglyceride content and parameters of lipid metabolism in plasma and liver based on mRNA abundance of associated genes. Fifty multiparous dairy cows were studied from wk 3 antepartum to approximately wk 17 p.p. in 2 periods. According to their energy balance in period 1 (parturition to wk 12 p.p.), cows were allocated to a control (CON; n = 25) or a restriction group (RES; 70% of energy requirements; n = 25) for 3 wk in mid lactation starting at around 100 d in milk (period 2). Liver triglyceride (TG) content, plasma nonesterified fatty acids (NEFA), and β-hydroxybutyrate were highest in wk 1 p.p. and decreased thereafter. During period 2, feed restriction did not affect liver TG and β-hydroxybutyrate concentration, whereas NEFA concentration was increased in RES cows as compared with CON cows. Hepatic mRNA abundances of tumor necrosis factor α, ATP citrate lyase, mitochondrial glycerol-3-phosphate acyltransferase, and glycerol-3-phosphate dehydrogenase 2 were not altered by lactational and energy status during both experimental periods. The expression of fatty acid synthase was higher in period 2 compared with period 1, but did not differ between RES and CON groups. The mRNA abundance of acetyl-coenzyme A-carboxylase showed a tendency toward higher expression during period 2 compared with period 1. The solute carrier family 27 (fatty acid transporter), member 1 (SLC27A1) was upregulated in wk 1 p.p. and also during feed restriction in RES cows. In conclusion, the present study shows that a NEB has different effects on hepatic lipid metabolism and TG concentration in the liver of dairy cows at early and later lactation. Therefore, the homeorhetic adaptations during the periparturient period trigger excessive responses in metabolism, whereas during the homeostatic control of endocrine and metabolic systems after established lactation, as during the period of feed restriction in the present study, organs are well adapted to metabolic and environmental changes.     

Peripartum performance and metabolism of dairy cows in response to prepartum energy and protein intake

Twenty-six multiparous Holstein cows were used to examine the effects of prepartum energy and protein intake on periparturient metabolism and lactation performance. Two levels of energy, 1.65 Mcal/kg of net energy for lactation (NEL) and 1.30 Mcal/kg of NEL, and two levels of protein, 17.0% CP and 12.5% CP, were tested according to a factorial arrangement in a randomized block design. Dietary treatments were fed ad libitum from 21 d before expected calving date to the day of calving. After calving, all cows were fed the same diet. Increased nutrient density did not affect prepartum feed intake, but postpartum intake was higher for cows fed the high-energy diets. Treatment had no effect on cow body weight and body condition score, however, cows fed the high-energy diets were in greater energy balance throughout the study. Milk and milk component yields were unaffected by treatment. Cows fed the high-energy diets had lower plasma nonesterified fatty acid concentrations than cows fed the low energy diets (354.3 vs. 439.9 mumol/L). Hepatic triglyceride concentrations were lower for cows on the high-energy diets than for those on the low-energy diets. Liver glycogen was unaffected by treatment. Acetyl-CoA carboxylase and fatty acid synthase abundance was significantly lower at calving than pretreatment, and higher for cows on the high-energy diets relative to those on the low-energy diets. The activity of acetyl-CoA carboxylase and lipoprotein lipase was greatly decreased with the onset of lactation. Increased protein intake prepartum resulted in elevated plasma beta-hydroxybutyrate concentrations postpartum. Prepartum plasma urea nitrogen was increased and 3-methylhistidine decreased by the high protein treatments. Overall, increased energy density of prepartum diets had beneficial effects on feed intake and lipid metabolism but did not improve lactation performance. Increasing the protein content of the prepartum diet did not appear to confer any advantages to cow productivity.