IRTA, Genètica i Millora Animal, 191 Rovira Roure, 25198 Lleida, Spain.
J Anim Sci. 2009 Dec;87(12):3905-14. doi: 10.2527/jas.2009-2091. Epub 2009 Aug 14.
The objectives of this study were 1) to determine whether selection toward less subcutaneous fat thickness at constant intramuscular fat content in pigs is related to tissue-specific changes in the expression of lipogenic enzymes acetyl-CoA carboxylase (ACC), stearoyl-CoA desaturase (SCD), and Delta(6)-desaturase (Delta6d); and 2) to investigate tissue specific distribution of the porcine ACC, SCD, and Delta6d. The study was conducted on 20 purebred Duroc barrows. Ten animals were from a group selected for decreased subcutaneous fat thickness at constant intramuscular fat content (experimental group). The other 10 animals were from the unselected (control) group. Distribution of ACC, SCD, and Delta6d was investigated in semimembranosus muscle (SM), subcutaneous adipose tissue (SA), liver (L), kidney (K), heart (H), diaphragm (D), rectus capitis muscle (RCM), and abdominal fat (AF). The enzyme expression was studied in 10 animals in the case of SM and SA and in 4 animals in the case of other tissues. The following expression pattern was established for ACC: SM <or= H = K <or= D < RCM < L < AF = SA, whereas the expression patterns for SCD and Delta6d proteins were SM < H < RCM < D < L < K < AF = SA and RCM = SM = D < L <or= H < SA < K < AF, respectively. Expression of ACC and SCD proteins was less in subcutaneous adipose tissue of the experimental animals when compared with the control group (P < 0.001). However, no difference (P > 0.1) in ACC and SCD protein expression between the control and experimental groups was observed in SM. Expression of Delta6d protein did not differ between the control and experimental groups for SA (P = 0.47) or SM (P = 0.31). There was a positive relationship between muscle SCD protein expression and intramuscular fat content (r = 0.48, P < 0.05). Intramuscular fat content did not correlate with ACC or Delta6d protein expression (P = 0.23 and P = 0.80, respectively). We conclude that SCD might be an effective potential biomarker for intramuscular fat deposition.
1）确定在猪肌肉内脂肪含量不变的情况下，皮下脂肪厚度选择减少是否与脂肪生成酶乙酰辅酶 A 羧化酶（ACC）、硬脂酰辅酶 A 去饱和酶（SCD）和 Delta(6)-去饱和酶（Delta6d）的组织特异性表达变化有关；2）研究猪 ACC、SCD 和 Delta6d 的组织特异性分布。该研究在 20 头纯种杜洛克公猪上进行。10 头动物来自皮下脂肪厚度选择减少而肌肉内脂肪含量不变的实验组（实验组）。其余 10 头动物来自未选择组（对照组）。在半腱肌（SM）、皮下脂肪组织（SA）、肝脏（L）、肾脏（K）、心脏（H）、膈肌（D）、头直肌（RCM）和腹部脂肪（AF）中研究了 ACC、SCD 和 Delta6d 的分布。在 SM 和 SA 的情况下，对 10 头动物的酶表达进行了研究，而在其他组织的情况下，对 4 头动物的酶表达进行了研究。建立了以下 ACC 表达模式：SM <= H = K <= D <= RCM < L < AF = SA，而 SCD 和 Delta6d 蛋白的表达模式分别为 SM < H < RCM < D < L < K < AF = SA 和 RCM = SM = D < L <= H < SA < K < AF。与对照组相比，实验组动物皮下脂肪组织中的 ACC 和 SCD 蛋白表达较低（P < 0.001）。然而，在 SM 中，实验组和对照组之间的 ACC 和 SCD 蛋白表达没有差异（P > 0.1）。在 SA（P = 0.47）或 SM（P = 0.31）中，Delta6d 蛋白的表达在对照组和实验组之间没有差异。肌肉 SCD 蛋白表达与肌肉内脂肪含量呈正相关（r = 0.48，P < 0.05）。肌肉内脂肪含量与 ACC 或 Delta6d 蛋白表达无关（P = 0.23 和 P = 0.80）。我们得出结论，SCD 可能是肌肉内脂肪沉积的有效潜在生物标志物。
