Department of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA.
Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, 60612, USA.
Mol Nutr Food Res. 2020 Jun;64(12):e2000059. doi: 10.1002/mnfr.202000059. Epub 2020 May 4.
Currently available omega-3 fatty acid supplements do not enrich the docosahexaenoic acid (DHA) of the adult brain because they are absorbed as triacylglycerol, whereas the transporter at the blood brain barrier requires lysophosphatidylcholine (LPC)-DHA. The hypothesis that treatment of krill oil (KO), which contains DHA/eicosapentaenoic acid (EPA) at the SN2 position of phosphatidylcholine, with SN1-specific lipase will generate LPC-DHA/EPA and which can be absorbed intact and transported into the brain, is tested.
KO and fish oil (FO) are treated with Mucor meihei lipase, incorporated into AIN 93G diet, and fed to 2-month-old mice for 30 days. Fatty acid composition is analyzed by gas chromatography/mass spectroscopy. Brain derived neurotrophic factor (BDNF) is measured by ELISA.
Lipase-treated (LT) KO increases brain DHA and EPA, respectively, 5-and 70-fold better than untreated (UT) KO. FO, whether lipase-treated or not, has no effect on brain DHA/EPA. LTKO is also more efficient in enriching liver DHA/EPA, but less efficient than UTKO and FO in enriching adipose tissue and heart. Brain BDNF is significantly increased by LTKO, but only marginally by other preparations.
Pretreatment of dietary KO with lipase enables it to efficiently increase brain DHA/EPA because of the generation of LPC-DHA/EPA.
目前可获得的ω-3 脂肪酸补充剂不会增加成人大脑中的二十二碳六烯酸 (DHA)，因为它们被吸收为三酰基甘油，而血脑屏障的转运体需要溶血磷脂酰胆碱 (LPC)-DHA。假设用 SN1 特异性脂肪酶处理富含 DHA/二十碳五烯酸 (EPA) 的磷酯酰胆碱 SN2 位的磷虾油 (KO)，会生成 LPC-DHA/EPA，且这些物质可以完整吸收并转运到大脑中，本研究对此进行了检验。
用米根霉脂肪酶处理 KO 和鱼油 (FO)，并将其掺入 AIN 93G 饮食中，然后喂给 2 月龄的小鼠 30 天。用气相色谱/质谱法分析脂肪酸组成。用 ELISA 法测量脑源性神经营养因子 (BDNF)。
经脂肪酶处理 (LT) 的 KO 分别使大脑 DHA 和 EPA 增加了 5 倍和 70 倍，而未经处理 (UT) 的 KO 则没有效果。未经处理或经脂肪酶处理的 FO 对大脑 DHA/EPA 均无影响。LTKO 还能更有效地增加肝脏 DHA/EPA，但在增加脂肪组织和心脏中的 DHA/EPA 方面不如 UTKO 和 FO 有效。LTKO 还显著增加了大脑 BDNF，但其他制剂仅略有增加。
用脂肪酶预处理膳食 KO 可有效地增加大脑 DHA/EPA，因为生成了 LPC-DHA/EPA。
