College of Animal Science and Technology, Inner Mongolia University for Nationalities, Tongliao, 028000, China.
Department of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, China.
Sci Rep. 2019 Sep 25;9(1):13846. doi: 10.1038/s41598-019-50243-8.
In this study, juvenile Manchurian trout, Brachymystax lenok (initial weight: 6.43 ± 0.02 g, mean ± SE) were received for nine weeks with five types of diets prepared by gradually replacing the proportion of fish oil (FO) with linseed oil (LO) from 0% (LO0) to 25% (LO25), 50% (LO50), 75% (LO75), and 100% (LO100). The eicosapentaenoic (EPA) and docosahexaenoic (DHA) composition decreased with increasing inclusion level of LO (P < 0.05). With increasing LO inclusion level, triglyceride (TAG) content of serum increased significantly, however, there was a decrease in high-density lipoprotein cholesterol (HDL) (P < 0.05). LO substitution of FO up-regulated the gene expression level of lipid metabolism-related genes Fatty Acid Desaturases 6 (FAD6), Acetyl-Coa Carboxylase (ACCα), Sterol Regulatory Element Binding Protein 1 (SREBP-1), and Sterol O- Acyl Transferase 2 (SOAT2), and down-regulated the gene expression level of Peroxisome Proliferator-Activated Receptor a (PPARα) (P < 0.05). The SOD activities of both serum and liver in LO100 were significantly lower than in LO25 (P < 0.05). The CAT activity of the liver in LO100 was significantly lower than in LO0 and LO25 (P < 0.05). This study indicates that the Manchurian trout may have the ability to synthesize LC-PUFAs from ALA, and an appropriate LO in substitution of FO (<75%) could improve both the lipid metabolism and the oxidation resistance.
在这项研究中，接收了初始体重为 6.43±0.02g（平均值±标准误差）的幼年哲罗鱼（Brachymystax lenok），并在 9 周内用五种不同类型的饲料喂养，这些饲料通过逐渐用亚麻籽油（LO）替代鱼油（FO）来制备，替代比例分别为 0%（LO0）、25%（LO25）、50%（LO50）、75%（LO75）和 100%（LO100）。随着 LO 添加水平的增加，二十碳五烯酸（EPA）和二十二碳六烯酸（DHA）的组成降低（P<0.05）。随着 LO 添加水平的增加，血清甘油三酯（TAG）含量显著增加，而高密度脂蛋白胆固醇（HDL）含量则降低（P<0.05）。用 LO 替代 FO 上调了与脂质代谢相关基因的表达水平，包括脂肪酸去饱和酶 6（FAD6）、乙酰辅酶 A 羧化酶（ACCα）、固醇调节元件结合蛋白 1（SREBP-1）和固醇 O-酰基转移酶 2（SOAT2），下调了过氧化物酶体增殖物激活受体α（PPARα）的基因表达水平（P<0.05）。LO100 组血清和肝脏中的 SOD 活性显著低于 LO25 组（P<0.05）。LO100 组肝脏中的 CAT 活性显著低于 LO0 和 LO25 组（P<0.05）。本研究表明，哲罗鱼可能具有从 ALA 合成 LC-PUFA 的能力，适量的 LO 替代 FO（<75%）可以改善脂质代谢和抗氧化能力。
