de Almeida Mariana Macedo, Luquetti Sheila Cristina Potente Dutra, Sabarense Céphora Maria, do Amaral Corrêa José Otávio, dos Reis Larissa Gomes, Santos da Conceição Ellen Paula, Lisboa Patrícia Cristina, de Moura Egberto Gaspar, Gameiro Jacy, da Gama Marco Antônio Sundfeld, Lopes Fernando César Ferraz, Garcia Raúl Marcel González
Department of Biology, Federal University of Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil.
Lipids Health Dis. 2014 Dec 22;13:200. doi: 10.1186/1476-511X-13-200.
Evidence from in vitro and animal studies indicates that conjugated linoleic acid (CLA) possesses anti-diabetic properties, which appear to be attributed to cis-9, trans-11 CLA, the major CLA isomer in ruminant fat. However, there is a shortage of studies addressing CLA from natural source. The present study aimed to evaluate the effects of butter naturally enriched in cis-9, trans-11 CLA on parameters related to glucose tolerance, insulin sensitivity and dyslipidemia in rats.
Forty male Wistar rats were randomly assigned to the following dietary treatments (n=10/group), for 60 days: 1) Normal fat-Soybean oil (NF-So): diet containing 4.0% soybean oil (SO); 2) High Fat-Control Butter (HF-Cb): diet containing 21.7% control butter and 2.3% SO; 3) High Fat-CLA enriched Butter (HF-CLAb): diet containing 21.7% cis-9, trans-11 CLA-enriched butter and 2.3% SO; and 4) High fat-Soybean oil (HF-So): diet containing 24.0% SO. HF-Cb and HF-CLAb diets contained 0.075% and 0.235% of cis-9, trans-11 CLA, respectively.
HF-CLAb-fed rats had lower serum insulin levels at fasting than those fed with the HF-Cb diet, while the PPARγ protein levels in adipose tissue was increased in HF-CLAb-fed rats compared to HF-Cb-fed rats. Furthermore, R-QUICK was lower in HF-Cb than in NF-So group, while no differences in R-QUICK were observed among NF-So, HF-CLAb and HF-So groups. Serum HDL cholesterol levels were higher in HF-CLAb-fed rats than in those fed NF-So, HF-Cb and HF-So diets, as well as higher in NF-So-fed rats than in HF-Cb and HF-So-fed rats. HF-CLAb, HF-Cb and HF-So diets reduced serum LDL cholesterol levels when compared to NF-So, whereas serum triacylglycerol levels were increased in HF-CLAb.
Feeding rats on a high-fat diet containing butter naturally enriched in cis-9, trans-11 CLA prevented hyperinsulinemia and increased HDL cholesterol, which could be associated with higher levels of cis-9, trans-11 CLA, vaccenic acid, oleic acid and lower levels of short and medium-chain saturated fatty acids from butter naturally modified compared to control butter. On the other hand CLA-enriched butter also increased serum triacylglycerol levels, which could be associated with concomitant increases in the content of trans-9 and trans-10 C18:1 isomers in the CLA-enriched butter.
体外和动物研究的证据表明，共轭亚油酸（CLA）具有抗糖尿病特性，这似乎归因于顺-9，反-11 CLA，它是反刍动物脂肪中的主要CLA异构体。然而，针对天然来源CLA的研究较少。本研究旨在评估天然富含顺-9，反-11 CLA的黄油对大鼠葡萄糖耐量、胰岛素敏感性和血脂异常相关参数的影响。
40只雄性Wistar大鼠被随机分配到以下饮食处理组（每组n = 10），持续60天：1）正常脂肪-大豆油（NF-So）：含有4.0%大豆油（SO）的饮食；2）高脂肪-对照黄油（HF-Cb）：含有21.7%对照黄油和2.3% SO的饮食；3）高脂肪-CLA富集黄油（HF-CLAb）：含有21.7%顺-9，反-11 CLA富集黄油和2.3% SO的饮食；4）高脂肪-大豆油（HF-So）：含有24.0% SO的饮食。HF-Cb和HF-CLAb饮食分别含有0.075%和0.235%的顺-9，反-11 CLA。
与喂食HF-Cb饮食的大鼠相比，喂食HF-CLAb的大鼠空腹血清胰岛素水平较低，而与HF-Cb喂养的大鼠相比，HF-CLAb喂养的大鼠脂肪组织中PPARγ蛋白水平升高。此外，HF-Cb组的R-QUICK低于NF-So组，而NF-So、HF-CLAb和HF-So组之间未观察到R-QUICK的差异。与喂食NF-So、HF-Cb和HF-So饮食的大鼠相比，喂食HF-CLAb的大鼠血清高密度脂蛋白胆固醇水平更高，与喂食HF-Cb和HF-So饮食的大鼠相比，NF-So喂养的大鼠血清高密度脂蛋白胆固醇水平也更高。与NF-So相比，HF-CLAb、HF-Cb和HF-So饮食降低了血清低密度脂蛋白胆固醇水平，而HF-CLAb组血清三酰甘油水平升高。
给大鼠喂食天然富含顺-9，反-11 CLA的高脂肪黄油饮食可预防高胰岛素血症并增加高密度脂蛋白胆固醇，这可能与顺-9，反-11 CLA、反式vaccenic酸、油酸水平较高以及与对照黄油相比天然改性黄油中短链和中链饱和脂肪酸水平较低有关。另一方面，富含CLA的黄油也增加了血清三酰甘油水平，这可能与富含CLA的黄油中反式-9和反式-10 C18:1异构体含量的同时增加有关。
