不同ω-6/ω-3多不饱和脂肪酸比例的大豆和鱼油混合物对右旋糖酐硫酸钠所致小鼠小肠上皮内淋巴细胞γδT-细胞表达变化的调节

　　为了调查不同ω-6/ω-3多不饱和脂肪酸（PUFA）比例对右旋糖酐硫酸钠（DSS）所致小肠上皮内淋巴细胞（IEL）γδT-细胞表达变化的影响，台北医学大学、国立台湾大学医院、中国文化大学开展了一项研究。

　　该研究将小鼠分为3个对照组和3个DSS治疗组，以低脂半纯化饮食喂养。一组对照（S）和一组DSS（DS）给予大豆油，其余两组对照（Hω-3和Lω-3）和两组DSS（DHω-3和DLω-3）给予ω-6/ω-3为2∶1或4∶1的大豆油和鱼油混合物。各自喂养2周后，分别给予DSS组含2%DSS的无菌水、对照组无菌水5天。给予所有组无菌水5天使其恢复，同时对小肠IELγδT-细胞进行分离并分析。

　　结果发现，DSS治疗引起小肠IELγδT-细胞百分比降低，RegIIIγmRNA表达、角质细胞生长因子（KGF）和IELγδT-细胞C5a受体（C5aR）升高。鱼油可以增加小肠IELγδT-细胞的比例。与DLω-3组相比，DHω-3组RegIIIγ、KGF以及C5aR的mRNA表达下降，而小肠IELγδT-细胞的过氧化物酶体增殖物激活受体（PPAR）-γ基因表达升高。

　　因此，鱼油饮食ω-6/ω-3 PUFA比例4∶1与2∶1相比，改善DSS所致小肠损伤更有效，并且肠道炎症缓解可能与IELγδT-细胞PPAR-γ激活有相关性。

JPEN J Parenter Enteral Nutr. 2016;40(3):383-91.

Soybean and Fish Oil Mixture With Different ω-6/ω-3 Polyunsaturated Fatty Acid Ratios Modulates Dextran Sulfate Sodium-Induced Changes in Small Intestinal Intraepithelial γδT-Lymphocyte Expression in Mice.

Pai MH, Liu JJ, Hou YC, Yeh CL.

Taipei Medical University, Taipei, Taiwan; National Taiwan University Hospital, Taipei, Taiwan; Chinese Culture University, Taipei, Taiwan.

BACKGROUND: This study investigated the effect of different ω-6/ω-3 polyunsaturated fatty acid (PUFA) ratios on dextran sulfate sodium (DSS)-induced changes to small intestinal intraepithelial lymphocyte (IEL) γδT-cell expression.

METHODS: Mice were assigned to 3 control and 3 DSS-treated groups and were maintained on a low-fat semipurified diet. One of the control (S) groups and a DSS (DS) group were provided with soybean oil; the other 2 control (Hω-3 and Lω-3) groups and 2 other DSS (DHω-3 and DLω-3) groups were fed either a soybean and fish oil mixture with a ω-6/ω-3 ratio of 2:1 or 4:1. After feeding the respective diets for 2 weeks, the DSS groups were given distilled water containing 2% DSS, and the control groups were given distilled water for 5 days. All groups were further provided distilled water 5 days for recovery, and the small intestinal IEL γδT-cell subset was isolated for analysis.

RESULTS: DSS treatment resulted in a lower small intestinal IEL γδT-cell percentage and higher messenger RNA (mRNA) expressions of Reg IIIγ, keratinocyte growth factor (KGF), and complement 5a receptor (C5aR) by IEL γδT cells. Fish oil administration enhanced the proportion of small intestinal IEL γδT cells. Compared with the DLω-3 group, the DHω-3 group had lower Reg IIIγ, KGF, and C5aR mRNA expressions and higher expression of peroxisome proliferator-activated receptor (PPAR)-γ gene by small intestinal IEL γδT cells.

CONCLUSIONS: Fish oil diets with a ω-6/ω-3 PUFA ratio of 2:1 were more effective than those with a ratio of 4:1 in improving DSS-induced small intestinal injury, and activation of PPAR-γ in IEL γδT cells may be associated with resolution of small intestinal inflammation.

KEYWORDS: dextran sulfate sodium; fish oil; peroxisome proliferator-activated receptor–γ; small intestinal intraepithelial lymphocyte; γδT cell; ω-6/ω-3 ratio

PMID: 25384382

DOI: 10.1177/0148607114559429