Smith D R, Knabe D A, Smith S B
Department of Animal Science, Texas Agricultural Experiment Station, Texas A&M University, College Station 77843-2471, USA.
J Anim Sci. 1996 May;74(5):975-83. doi: 10.2527/1996.745975x.
The objective of this study was to document the influence of specific dietary fatty acids on rates of lipid synthesis and sensitivity to insulin in porcine adipose tissue. Weanling pigs were assigned to one of six groups, and each group was fed diets containing 10 g/100 g of added cornstarch or 10 g/100 g of added fatty acid. The fatty acid-enriched diets contained either a combination of 14:1 plus 16:1 (14:1/16:1 diet), 16:0, 18:0, 18:1, or 18:2 (n-6). With the exception of the cornstarch diet, all diets contained approximately 35% 14:0. Subcutaneous adipose tissue samples were collected at slaughter from the area overlying the first cranial vertebra. Fresh samples were incubated for 2 h in 20 mM glucose and 0, 10, 100 or 1,000 microU/mL of porcine insulin. The smallest adipocytes were observed in adipose tissue from pigs fed the 16:0 or 18:2 diets. Glucose incorporation into lipids was greater (P < .05) in adipose tissue from cornstarch-fed pigs than in adipose tissue from the other treatment groups. Lipogenesis was 67, 53, 35, 32, and 20% lower (P < .05) in adipose tissue from 16:0-, 14:1/16:1-, 18:0-, 18:2-, and 18:1-fed pigs, respectively, than in adipose tissue from the cornstarch-fed pigs. Insulin increased lipogenesis by 19% (P < .05) in adipose tissue from the cornstarch-fed pigs and by 15 to 40% (P < .05) in adipose tissue from the 14:1/16:1-fed pigs. Insulin did not stimulate lipogenesis (P > .4) in adipose tissue from pigs fed the 16:0, 18:0, or 18:1 diets. The data suggest that fatty acid chain length and unsaturation are determinants in the effects of dietary fat and insulin on de novo lipogenesis.
本研究的目的是记录特定膳食脂肪酸对猪脂肪组织中脂质合成速率和胰岛素敏感性的影响。断奶仔猪被分为六组之一，每组饲喂含有10 g/100 g添加玉米淀粉或10 g/100 g添加脂肪酸的日粮。富含脂肪酸的日粮含有14:1加16:1的组合（14:1/16:1日粮）、16:0、18:0、18:1或18:2（n-6）。除玉米淀粉日粮外，所有日粮均含有约35%的14:0。在屠宰时从第一颈椎上方区域采集皮下脂肪组织样本。新鲜样本在含有20 mM葡萄糖和0、10、100或1000微单位/毫升猪胰岛素的条件下孵育2小时。在饲喂16:0或18:2日粮的猪的脂肪组织中观察到最小的脂肪细胞。与其他处理组的脂肪组织相比，饲喂玉米淀粉日粮的猪的脂肪组织中葡萄糖掺入脂质的量更大（P < 0.05）。与饲喂玉米淀粉日粮的猪的脂肪组织相比，饲喂16:0、14:1/16:1、18:0、18:2和18:1日粮的猪的脂肪组织中脂肪生成分别降低了67%、53%、35%、32%和20%（P < 0.05）。胰岛素使饲喂玉米淀粉日粮的猪的脂肪组织中的脂肪生成增加了19%（P < 0.05），使饲喂14:1/16:1日粮的猪的脂肪组织中的脂肪生成增加了15%至40%（P < 0.05）。胰岛素对饲喂16:0、18:0或18:1日粮的猪的脂肪组织中的脂肪生成没有刺激作用（P > 0.4）。数据表明，脂肪酸链长度和不饱和度是膳食脂肪和胰岛素对从头脂肪生成影响的决定因素。
