DeClercq Vanessa, Zahradka Peter, Taylor Carla G
Department of Human Nutritional Sciences, University of Manitoba, Winnipeg, MB, R2H 2A6, Canada.
Lipids. 2010 Nov;45(11):1025-33. doi: 10.1007/s11745-010-3469-1. Epub 2010 Sep 16.
In obesity, increased activity of the local renin-angiotensin system (RAS) and enlarged adipocytes with altered adipokine production are linked to the development of obesity-related health problems and cardiovascular disease. Mixtures of conjugated linoleic acid (CLA) isomers have been shown to reduce adipocyte size and alter the production of adipokines. The objective of this study was to investigate the effects of feeding individual CLA isomers on adipocyte size and adipokines associated with the local adipose RAS. Male fa/fa Zucker rats received either (a) control, (b) cis(c)9,trans(t)11-CLA, or (c) t10,c12-CLA diet for 8 weeks. The t10,c12-CLA isomer reduced adipocyte size and increased cell number in epididymal adipose tissue. RT-PCR and Western blot analysis revealed that neither CLA isomer altered mRNA or protein levels of angiotensinogen or AngII receptors in adipose tissue. Likewise, levels of the pro-inflammatory cytokines TNF-α and IL-6 or the anti-inflammatory cytokine IL-10 were unchanged in adipose tissue. Similarly, neither CLA isomer had any effect on phosphorylation nor DNA binding of NF-κB. Our results suggest that although the t10,c12-CLA isomer had beneficial effects on reducing adipocyte size in obese rats, this did not translate into changes in the local adipose RAS or associated adipokines.
在肥胖症中，局部肾素-血管紧张素系统（RAS）活性增加以及脂肪细胞增大且脂肪因子产生改变，与肥胖相关健康问题和心血管疾病的发生有关。共轭亚油酸（CLA）异构体混合物已被证明可减小脂肪细胞大小并改变脂肪因子的产生。本研究的目的是调查喂食单个CLA异构体对脂肪细胞大小以及与局部脂肪RAS相关的脂肪因子的影响。雄性fa/fa Zucker大鼠接受以下饮食8周：（a）对照饮食，（b）顺式（c）9，反式（t）11-CLA饮食，或（c）反式（t）10，顺式（c）12-CLA饮食。反式（t）10，顺式（c）12-CLA异构体减小了附睾脂肪组织中的脂肪细胞大小并增加了细胞数量。逆转录聚合酶链反应（RT-PCR）和蛋白质免疫印迹分析显示，两种CLA异构体均未改变脂肪组织中血管紧张素原或血管紧张素II受体的mRNA或蛋白质水平。同样，脂肪组织中促炎细胞因子肿瘤坏死因子-α（TNF-α）和白细胞介素-6（IL-6）或抗炎细胞因子白细胞介素-10（IL-10）的水平未发生变化。同样，两种CLA异构体对核因子κB（NF-κB）的磷酸化或DNA结合均无影响。我们的结果表明，尽管反式（t）10，顺式（c）12-CLA异构体对降低肥胖大鼠的脂肪细胞大小有有益作用，但这并未转化为局部脂肪RAS或相关脂肪因子的变化。
