急性冷刺激后巴马猪背膘和腹股沟皮下脂肪组织的脂质组比较

本研究旨在获得巴马猪皮下脂肪组织（包括背膘（backfat）和腹股沟皮下脂肪组织（inguinal subcutaneous white adipose tissue，iWAT））在急性冷刺激（4 ℃、4 h）后其脂质组成应答的差异。正常饲喂的6月龄巴马公猪在急性冷刺激处理后进行屠宰，收集背膘和腹股沟皮下脂肪组织，利用液相二级质谱（LC-MS/MS）高通量脂质组学检测技术分析其脂质组成。结果表明，在巴马猪皮下脂肪组织中，中性脂类、游离脂肪酸、磷脂类和鞘脂类4大类脂质含量差异巨大，其中含量最高的为中性脂类，在腹股沟皮下脂肪组织和背膘中分别占4大脂类总和的97.43%和98.53%；含量最低的为鞘脂类，在腹股沟皮下脂肪组织和背膘中所占比例分别为0.10%和0.07%。在16亚类脂质组成中含量最高的脂质为甘油三酯，在腹股沟皮下脂肪组织和背膘分别占16亚类脂质总和的95.97%和97.33%；含量最低的脂质为磷脂酸，在腹股沟皮下脂肪组织和背膘中所占比例分别为3.98E-04%和1.13E-04%。主成分分析表明，背膘和腹股沟皮下脂肪组织在急性冷刺激后脂质组成存在差异。以∣差异倍数∣>1.5和P<0.05为标准筛选，共获得18种差异显著的脂类，其中16种脂类在背膘中含量显著低于腹股沟皮下脂肪组织，其中包括14种甘油三酯、DAG32：1（16：1/16：0）和PE40：6p；只有2种脂质（CL74：8（18：2）和TAG54：3（16：0））在背膘中的含量显著高于腹股沟皮下。巴马猪皮下脂肪主要脂质组成为甘油三酯；急性冷刺激后，背膘和腹股沟皮下脂肪组织对急性冷刺激存在不同的应答。

Comparison of Lipid Profiles of Backfat and Inguinal Subcutaneous White Adipose Tissue from Acute Cold-treated Bama Pigs

This experiment aimed to study the difference of lipid metabolism between backfat and inguinal subcutaneous white adipose tissue (iWAT) after acute cold exposure (4 ℃ for 4 h).The LC-MS/MS based lipidomics of backfat and iWAT from chow diet-fed and cold-treated six-month-old male Bama pigs were profiled.The results showed that the content of 4 lipids classes,including neutral lipids,free fatty acids,phospholipids and sphingolipids were varies greatly in iWAT of Bama pigs.The highest lipid class in both iWAT and backfat was neutral lipids,which accounted for 97.43% and 98.53% respectively;The lowest lipid class was sphingolipids,which accounted for 0.10%and 0.07% in iWAT and backfat,respectively.Among 16 subclass lipids,the highest content in iWAT and backfat was TAG,which accounted for 95.97% and 97.33%,respectively,while the lowest content was PA,which accounted for 3.98E-04% and 1.13E-04% in iWAT and backfat,respectively.PCA analysis showed that backfat and iWAT could be separated clearly,which indicated the distinct changes in lipid composition of both fat tissues.And 18 different lipid species were determined using a criteria of fold change>1.5 and P<0.05,the results showed that 16 lipid species were significantly downregulated in backfat,including 14 TAGs,DAG32:1 (16:1/16:0) and PE40:6p.Two lipid species,including CL74:8(18:2) and TAG54:3 (16:0),were observed to be upregulated in backfat.The above results indicated that TAG was the main content of iWAT in Bama pigs,the backfat and iWAT had different physiological responses for acute cold stimulation.