Effects of dietary l-carnitine supplementation on growth and lipid metabolism in European seabass (Dicentrarchus labrax)   总被引：1，自引：0，他引：1  

J Dias  J Arzel  G Corraze  & J Kaushik 《Aquaculture Research》2001,32(S1):206-215

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Adipose tissue gene expression in obese dogs after weight loss   总被引：1，自引：0，他引：1  

Leray V  Serisier S  Khosniat S  Martin L  Dumon H  Nguyen P 《Journal of animal physiology and animal nutrition》2008,92(3):390-398

Body weight (BW) mainly depends on a balance between fat storage (lipogenesis) and fat mobilization (lipolysis) in adipocytes. BW changes play a role in insulin resistance (IR), the inability of insulin target tissue to respond to physiological levels of insulin. This results in inhibition of lipogenesis and stimulation of lipolysis. Weight gain leads to IR whereas, weight loss improves insulin sensitivity (IS). The aim of this study was to evaluate the effect of weight loss and recovery of IS on the expression of genes involved in lipogenesis and lipolysis in weight losing dogs. Gene expression was studied in both subcutaneous and visceral adipose tissue. Obese dogs received a hypoenergetic low fat high protein diet (0.6 x NRC recommendation). Before and after weight loss, IS was assessed using the euglycaemic hyperinsulinaemic clamp. Gene expression of IRS-2, SREBP, intracellular insulin effectors, ACC, FAS, FABP, ADRP, PEPCK, lipogenesis key proteins, perilipin and HSL, lipolysis key proteins were quantified using real-time RT-PCR in subcutaneous and visceral fat. BW decreased from 15.2 +/- 0.5 to 11.4 +/- 0.4 kg (p < 0.05) over 78 +/- 8 days. When obese, dogs were insulin resistant. After weight loss, IS was improved. In the subcutaneous adipose tissue, the expression of only the IRS-2 was increased. In the visceral adipose tissue, the expression of the genes involved in the lipogenesis was decreased whereas one of the genes implied in the lipolysis did not change. The expression profile of genes involved in lipid metabolism, as measured after weight loss, is indicative for a lower lipogenesis after weight loss than in obese dogs. Our results also confirm dramatic differences in the lipid metabolism of visceral and subcutaneous fat. They should be completed by comparing gene expression during weight losing and normal weight steady state.  相似文献   

Influence of dietary lipid on growth performance and some lipogenesis‐related gene expression of tongue sole (Cynoglossus semilaevis) larvae          下载免费PDF全文

Yuhui Yuan  Songlin Li  Lu Zhang  Kangsen Mai  Wei Xu  Qinghui Ai 《Aquaculture Research》2017,48(3):767-779

A 30‐day feeding trial was conducted to investigate the effects of dietary lipid levels on growth performance, activities of digestive enzymes, fatty acid composition and some lipogenesis‐related gene expression of half‐smooth tongue sole (Cynoglossus semilaevis) larvae. Five isoproteic diets were formulated with graded lipid levels (6.68%, 9.84%, 13.47%, 17.89% and 21.88% dry weight) using fish oil as the main lipid source. Each diet was randomly allocated to triplicate groups of 150 larval tongue sole (35 DAH, 54 ± 1 mg). Fish were fed five times daily to apparent satiation during the feeding experiment. Results showed that, the survival rate (SR) of larvae increased significantly firstly, and thereafter decreased significantly. The specific growth rates (SGR) of larvae fed the diet with 13.47% lipid were significantly higher than other treatments. Larvae fed 9.84% or 13.47% dietary lipid showed higher trypsin, lipase, leucine aminopeptidase and alkaline phosphatase (AP) activities than other treatments, whereas amylase activity nearly showed reverse trend with them. The fatty acid composition of the tongue sole larvae was well correlated with dietary fatty acid profile. Expression of acetyl‐CoA carboxylase alpha (ACC1) was found to be slightly negatively correlated with dietary lipid level, and high dietary lipid level depressed the expressions of acetyl‐CoA carboxylase beta (ACC2) and fatty acid synthase (FAS) mRNA expression significantly, implying that larvae may cope with high dietary lipid mainly through down‐regulating lipogenesis‐related gene expression of FAS and ACC2. Besides, on the basis of SGR, the optimal dietary lipid level for larval tongue sole was estimated to be 13.56% using second‐order polynomial curve.  相似文献   

Assessment of dietary lipid sources in tropical gar,Atractosteus tropicus larvae: Growth parameters and intermediary lipogenic gene expression     

Luis Daniel Jimnez‐Martínez  Dariel Tovar‐Ramírez  Carlos Alfonso lvarez‐Gonzlez  Emyr Pea‐Marín  Susana Camarillo‐Coop  Rafael Martínez‐García  Elena Palacios‐Mechetnov  Rosario Martínez‐Yaez  Bartolo Concha‐Frías 《Aquaculture Research》2020,51(7):2629-2640

Five experimental diets containing different lipid sources, fish oil (D1), soybean lecithin (D2), corn oil (D3), canola oil (D4) and olive oil (D5), were evaluated in Atractosteus tropicus larvae for the relative gene expression of the enzymes fatty acid synthase (fas), acetyl‐CoA carboxylase 1 (acc1) and carnitine palmitoyltransferase 1C (cpt1c), in addition to their effects on larval growth, survival and cannibalism during a 30‐day feeding trial. Higher growth and survival were obtained in treatments D1 and D2, and lower performance in diets D3, D4 and D5. The highest levels of expression of fas and acc1 occurred in larvae fed with D1, which contained high amounts of n‐3 long‐chain polyunsaturated fatty acids (LC‐PUFA), mainly DHA and EPA FA are regulators of lipogenesis. The higher cpt1c expression in plant‐based diets is attributed to the fact that these diets are rich in α‐linolenic acid (ALA) and low DHA, EPA and ARA levels that favour ß‐oxidation. In conclusion, the diets with fish oil (D1) and soybean lecithin (D2) were the best treatments for larval growth, survival and cannibalism and thus appear to meet both lipid and energy requirements of A. tropicus larvae, meanwhile the use of vegetable oils influences the expression of intermediary lipogenic genes.  相似文献   

Effect of short‐chain fatty acids on triacylglycerol accumulation,lipid droplet formation and lipogenic gene expression in goat mammary epithelial cells          下载免费PDF全文

Yuting Sun  Jun Luo  Jiangjiang Zhu  Hengbo Shi  Jun Li  Siyuan Qiu  Ping Wang  Juan J. Loor 《Animal Science Journal》2016,87(2):242-249

Short‐chain fatty acids (SCFAs) are the major energy sources for ruminants and are known to regulate various physiological functions in other species. However, their roles in ruminant milk fat metabolism are still unclear. In this study, goat mammary gland epithelial cells (GMECs) were treated with 3 mmol/L acetate, propionate or butyrate for 24 h to assess their effects on lipogenesis. Data revealed that the content of triacylglycerol (TAG) and lipid droplet formation were significantly stimulated by propionate and butyrate. The expression of FABP3, SCD1, PPARG, SREBP1, DGAT1, AGPAT6 and ADRP were upregulated by propionate and butyrate treatment. In contrast, the messenger RNA (mRNA) expression of FASN and LXRα was not affected by propionate, but reduced by butyrate. Acetate had no obvious effect on the content of TAG and lipid droplets but increased the mRNA expression of SCD1 and FABP3 in GMECs. Additionally, it was observed that propionate significantly increased the relative content of mono‐unsaturated fatty acids (C18:1 and C16:1) at the expense of decreased saturated fatty acids (C16:0 and C18:0). Butyrate and acetate had no significant effect on fatty acid composition. Overall, the results from this work help enhance our understanding of the regulatory role of SCFAs on goat mammary cell lipid metabolism.  相似文献   

Hepatic glucose utilization and lipogenesis of hybrid striped bass (Morone chrysops × Morone saxatilis) in response to dietary carbohydrate level and complexity     

S.D. RAWLES  S.B. SMITH  & D.M. GATLIN III 《Aquaculture Nutrition》2008,14(1):40-50

The influence of carbohydrate level and complexity on in vitro hepatic glucose utilization and lipogenesis were determined in hybrid striped bass, Morone chrysops ♀ × Morone saxatilis ♂. Six isocaloric, isonitrogenous diets containing glucose, maltose, or dextrin at two different levels (200 or 400 g kg^?1 diet) were fed to adult fish for 15 weeks. Liver explants were obtained at near‐maximum postprandial glycaemic response and incubated with radioactive labelled substrates. Glycogen synthesis from [¹⁴C]glucose was not different among treatments and was less than ¹⁴CO₂ formation. ¹⁴CO₂ production increased as a function of carbohydrate level but was unrelated to carbohydrate complexity. There was no detectable conversion of [¹⁴C]glucose to lactate for any treatment. Rates of de novo lipogenesis from [1‐¹⁴C]acetate were high in comparison to [U‐¹⁴C]glucose or [9,10‐³H]palmitate incorporation into liver lipids and differed in response to carbohydrate level and complexity. [9,10‐³H]palmitate esterification was an order of magnitude less than glycogen and CO₂ production but 4–10 times greater than [¹⁴C]glucose incorporation into liver lipids. Palmitate incorporation did not differ among treatments. Incorporation of [¹⁴C]glucose into liver lipids was higher in fish fed diets containing 400 g kg^?1 carbohydrate. These data support the idea that glucose is not a major oxidative substrate in hybrid striped bass and indicate that the level of soluble carbohydrate should be limited to 200 g kg^?1 diet or less for hybrid striped bass.  相似文献   

Insulin stimulates hepatic lipogenesis in rainbow trout,Oncorhynchus mykiss     

Darrin J. Cowley  Mark A. Sheridan 《Fish physiology and biochemistry》1993,11(1-6):421-428

The effects of the pancreatic hormones, insulin and glucagon, on rates of lipid biosynthesis in liver removed from rainbow trout, Oncorhynchus mykiss, were evaluated in vitro. Livers were removed from animals fasted for 30–36h, cut into ca. 1 mm³ pieces, and incubated in the presence of various concentrations of salmon insulin (sINS), bovine insulin (bINS), or a combination of BINS and bovine/porcine glucagon (GLU). Lipid synthesis was evaluated by total lipid concentration, ³H₂O incorporation into total lipid, and by fatty acid synthetase activity. Both mammalian and sINS tended to increase tissue total lipid concentration in hepatic tissue incubated for 5h. Insulin also stimulated ³H₂O incorporation into total lipid in a dose-dependent manner. Bovine INS (2 × 10^?6 M) stimulated de novo synthesis nearly 6-fold over control rates; sINS (2 × 10^?6 M) stimulated label incorporation more than 7-fold over control rates. Glucagon inhibited INS-stimulated ³H₂O incorporation; whereas, GLU alone had no effect on lipid synthesis in liver pieces incubated 5h. Lipid class analysis indicated that bINS significantly stimulated ³H₂O incorporation into phospholipids, fatty acids, and triacylglycerols. The greatest accumulation of label was in the triacylglycerol fraction, where incorporation was stimulated 17-fold over control levels. Hepatic enzymatic analysis indicated that bINS also significantly stimulated lipogenic enzyme activity 9-fold above control levels. These results indicate that INS is an important regulator of lipid synthesis in the liver of trout.  相似文献   

脂肪与肥胖相关基因和脂肪形成关系的研究进展     

孙宗扬  王金泉  蒙建菊  王俊丽 《动物医学进展》2017,38(2)

脂肪与肥胖相关(FTO)基因是一个与人类肥胖紧密相关的基因。自该基因被确定后,建立了各种动物模型来探究FTO基因与肥胖之间可能存在的联系机制,早期的许多研究主要集中于FTO基因通过中枢调节食物摄入量的机制方面。然而,新的研究发现脂肪组织的发育及功能与FTO基因和肥胖存在一定的关联,FTO基因在脂肪的形成中发挥一定的作用,研究包括FTO基因对脂肪细胞形成的影响,对脂肪形成过程中的影响,在脂肪形成中的催化作用以及影响脂肪形成机制的影响,主要探讨了FTO基因对脂肪组织和肥胖的影响。随分子生物学技术的不断改进及发展,FTO基因等多个与肥胖、脂肪相关的酶被发现和关注,这些酶的研究将为防治肥胖提供更多的理论依据。  相似文献   

胰岛素对原代培养猪脂肪细胞生脂和脂解相关基因转录表达及脂代谢的影响     

卢建雄  杨公社  陈粉粉 《农业生物技术学报》2006,14(1):11-16

为了研究体外胰岛素对猪脂肪组织脂肪代谢及相关基因表达的影响,对取自于7日龄大白×长白杂种仔猪皮下脂肪组织的脂肪细胞,经原代培养,用0!400nmol/L胰岛素处理48h,采用油红O染色提取、甘油试剂盒和半微量RT-PCR分别测定了脂肪细胞生脂和脂解的累计变化,以及转录因子固醇调控元件结合蛋白(SREBP)-1c和碳水化合物反应元件结合蛋白(ChREBP)、脂肪酸合成酶(FAS)、乙酰辅酶A羧化酶(ACC1)和激素敏感脂酶(HSL)基因mRNA水平的变化。结果表明,低糖条件下(5mmol/L)下,胰岛素不影响原代培养猪脂肪细胞ChREBP和ACC1转录表达;胰岛素(200nmol/L例外)明显促进FAS转录表达,100!300nmol/L也显著增强SREBP-1c表达。但二者表达变化不一致,在原代猪脂肪细胞胰岛素是否是通过SREBP-1c途径调控FAS转录尚待进一步研究;高浓度胰岛素(300!400nmol/L)显著促进脂肪细胞HSL表达和脂解活性。  相似文献   

血清剥夺对原代培养大鼠脂肪细胞脂代谢相关基因转录表达的影响     

卢建雄  杨公社  陈粉粉 《畜牧兽医学报》2007,38(1):46-52

利用血清剥夺／血清培养实验模型，采用油红O染色提取法、甘油试剂盒和RT-PCR，诱导和测定了大鼠附睾脂肪垫分离和培养的脂肪细胞生脂和脂解及其相关酶和转录因子mRNA水平的变化，探讨脂肪细胞脂代谢通路中关键酶和转录因子基因转录表达的规律。结果显示，依血清剥夺时间延长，脂肪细胞激素敏感脂酶（HSL）mRNA表达水平显著提高（P〈0．05），恢复血清培养后，表达水平显著降低（P〈0．05），与脂解活性的变化一致；脂肪生成及生脂相关基因脂肪酸合酶（FAS）、乙酰辅酶A羧化酶（ACC1）和碳水化合物反应元件结合蛋白（ChREBP）mRNA表达水平依血清剥夺持续时间明显下降（P〈0．05），恢复血清培养，随培养时间延长显著提高（P〈0．05）；血清剥夺显著降低固醇调控元件结合蛋白（SREBP）-1cmRNA水平，但血清剥夺72h与36h无明显差异（P〉0．05）；血清剥夺72h后恢复血清培养36h和72h，SREBP-1cmRNA的表达水平没有显著性变化（P〉0．05）。结果表明，生脂及FAS和ACC1表达与ChREBP mRNA水平一致，但与SREBP-1c不一致，提示ChREBP与成熟脂肪细胞生脂基因转录激活可能有更密切的关系，但尚待在蛋白水平进一步证实。  相似文献