Department of Biochemistry, Memorial University, St. John's, NL, Canada.
Department of Biochemistry, Memorial University, St. John's, NL, Canada;
Food Nutr Res. 2015 Mar 20;59:25866. doi: 10.3402/fnr.v59.25866. eCollection 2015.
The effects of long-chain n-3 and n-6 polyunsaturated fatty acids (PUFA) on the regulation of adipocytes metabolism are well known. These fatty acids are generally consumed together in our diets; however, the metabolic regulation of adipocytes in the presence of these fatty acids when given together is not known.
To investigate the effects of n-3 PUFA and arachidonic acid (AA), an n-6 PUFA, on the regulation of adipogenic and lipogenic genes in mature 3T3-L1 adipocytes.
3T3-L1 adipocytes were incubated in the presence or absence of 100 µM of eicosapentaenoic acid, EPA; docosahexaenoic acid, DHA; docosapentaenoic acid, DPA and AA, either alone or AA+n-3 PUFA; control cells received bovine serum albumin alone. The mRNA expression of adipogenic and lipogenic genes was measured. The fatty acid composition of adipocytes was analyzed using gas chromatography.
Individual n-3 PUFA or AA had no effect on the mRNA expression of peroxisome-proliferator-activated receptor-γ; however, AA+EPA and AA+DPA significantly increased (P<0.05) the expression compared to control cells (38 and 42%, respectively). AA and AA+EPA increased the mRNA expression of acetyl-CoA carboxylase 1 (P<0.05). AA treatment decreased the mRNA expression of stearoyl-CoA desaturase (SCD1) (P<0.01), while n-3 PUFA, except EPA, had no effect compared to control cells. AA+DHA and AA+DPA inhibited SCD1 gene expression (P<0.05) suggesting a dominant effect of AA. Fatty acids analysis of adipocytes revealed a higher accretion of AA compared to n-3 PUFA.
Our findings reveal that AA has a dominant effect on the regulation of lipogenic genes in adipocytes.
长链 n-3 和 n-6 多不饱和脂肪酸 (PUFA) 对脂肪细胞代谢的调节作用众所周知。这些脂肪酸通常在我们的饮食中一起摄入；然而，当这些脂肪酸一起给予时，脂肪细胞代谢的调节尚不清楚。
研究 n-3 PUFA 和花生四烯酸 (AA)，一种 n-6 PUFA，对成熟 3T3-L1 脂肪细胞中成脂和脂基因调节的影响。
3T3-L1 脂肪细胞在存在或不存在 100µM 二十碳五烯酸 (EPA)、二十二碳六烯酸 (DHA)、二十二碳五烯酸 (DPA) 和 AA 的情况下孵育，单独或 AA+n-3 PUFA；对照细胞单独接受牛血清白蛋白。测量成脂和脂基因的 mRNA 表达。使用气相色谱法分析脂肪细胞的脂肪酸组成。
单独的 n-3 PUFA 或 AA 对过氧化物酶体增殖物激活受体-γ的 mRNA 表达没有影响；然而，AA+EPA 和 AA+DPA 与对照细胞相比显著增加 (P<0.05) (分别为 38%和 42%)。AA 和 AA+EPA 增加乙酰辅酶 A 羧化酶 1 的 mRNA 表达 (P<0.05)。AA 处理降低硬脂酰辅酶 A 去饱和酶 1 (SCD1) 的 mRNA 表达 (P<0.01)，而 n-3 PUFA 与对照细胞相比没有影响。AA+DHA 和 AA+DPA 抑制 SCD1 基因表达 (P<0.05)，表明 AA 具有主导作用。脂肪细胞脂肪酸分析显示 AA 的积累高于 n-3 PUFA。
我们的研究结果表明，AA 对脂肪细胞中脂基因的调节具有主导作用。
