Department of Biochemistry, Memorial University, St. John's, NL A1B3X9, Canada.
Food Funct. 2014 Dec;5(12):3287-95. doi: 10.1039/c4fo00330f.
Omega (n)-3 polyunsaturated fatty acids (PUFA), namely docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), are known to reduce the risk of insulin resistance and ameliorate obesity-associated disorders. DHA and EPA structured in the phospholipid form possess superior biological effects compared to the triglyceride form available in fish oil. In this study, we have found that sea cucumber (SC) and blue mussel (BM) from Newfoundland and Labrador are rich sources of n-3 PUFA structured in the phospholipid form. Treatment with SC and BM methanolic extracts (250 and 100 μg mL(-1), respectively) significantly (p < 0.01) increased triglyceride accumulation in 3T3-L1 adipocytes, along with an increase in the mRNA expression of the peroxisome proliferator-activated receptor-γ (37 and 39%, respectively) and adiponectin (57 and 56%, respectively) compared with control cells (p < 0.05). Only SC extracts (250 μg mL(-1)) increased the mRNA expression of sterol regulatory element-binding protein-1 (SREBP-1). Treatment with higher concentrations of SC and BM extracts (500 and 750 μg mL(-1), respectively) significantly (p < 0.01) decreased triglyceride accumulation in 3T3-L1 cells as opposed to an increase in triglyceride accumulation at lower concentrations. This was due to inhibition of acetyl-CoA carboxylase-1 and SREBP-1 mRNA expression compared to control cells (p < 0.05). There was no effect of the extracts on the mRNA expression of hormone sensitive lipase or lipolysis, suggesting that the decrease in triglyceride accumulation at higher concentrations is not due to breakdown and release of fat. This is the first report to show that SC and BM are new sources of phospholipid bonded n-3 PUFA, with the potential to target insulin resistance and obesity.
ω-3 多不饱和脂肪酸（PUFA），即二十二碳六烯酸（DHA）和二十碳五烯酸（EPA），已知可降低胰岛素抵抗的风险并改善与肥胖相关的疾病。DHA 和 EPA 以磷脂形式存在，其具有比鱼油中可用的甘油三酯形式更优越的生物学效应。在这项研究中，我们发现来自纽芬兰和拉布拉多的海参（SC）和贻贝（BM）是富含 n-3 PUFA 以磷脂形式存在的丰富来源。SC 和 BM 甲醇提取物（分别为 250 和 100μg/mL）处理可显著（p<0.01）增加 3T3-L1 脂肪细胞中的甘油三酯积累，同时与对照细胞相比，过氧化物酶体增殖物激活受体-γ（分别增加 37%和 39%）和脂联素（分别增加 57%和 56%）的 mRNA 表达增加（p<0.05）。只有 SC 提取物（250μg/mL）增加了固醇调节元件结合蛋白-1（SREBP-1）的 mRNA 表达。与低浓度相比，用较高浓度的 SC 和 BM 提取物（分别为 500 和 750μg/mL）处理会显著（p<0.01）减少 3T3-L1 细胞中的甘油三酯积累，而不是增加甘油三酯积累。这是由于与对照细胞相比，乙酰辅酶 A 羧化酶-1 和 SREBP-1 mRNA 表达的抑制（p<0.05）。提取物对激素敏感脂肪酶或脂肪分解的 mRNA 表达没有影响，这表明在较高浓度下甘油三酯积累的减少不是由于脂肪的分解和释放。这是首次报道海参和贻贝是新的磷脂结合 n-3 PUFA 来源，具有靶向胰岛素抵抗和肥胖的潜力。
