Morifuji Masashi, Kitade Masami, Oba Chisato, Fukasawa Tomoyuki, Kawahata Keiko, Yamaji Taketo, Manabe Yuki, Sugawara Tatsuya
Food Science Research Labs, Meiji Co. Ltd., 540 Naruda, Odawara-shi, Kanagawa, 250-0862, Japan.
Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kitashirakawaoiwakecho, Sakyo-ku, Kyoto-shi, Kyoto, 606-8502, Japan.
Lipids. 2017 May;52(5):423-431. doi: 10.1007/s11745-017-4247-0. Epub 2017 Mar 29.
Supplementation with sphingomyelin has been reported to prevent disease and maintain good health. However, intact sphingomyelin and ceramides are poorly absorbed compared with glycerolipids. Therefore, if the bioavailability of dietary sphingomyelin can be increased, supplementation would be more effective at lower doses. The aim of this study in rats was to evaluate the effect of fermented milk on the bioavailability of dietary sphingomyelin in rats. After the rats had fasted for 15 h, test solutions were administrated orally. Blood samples were collected from the tail vein before and 90, 180, 270, and 360 min after administration. Compared with sphingomyelin/milk phospholipids concentrate (MPL) alone, co-ingestion of sphingomyelin/MPL with fermented milk caused an approximate twofold significant increase in serum ceramides containing d16:1 sphingosine with 16:0, 22:0, 23:0 and 24:0 fatty acids, which was derived from the ingested sphingomyelin. While nonfat milk also increased the serum levels of these ceramides, fermented milk was more effective. Co-ingestion of the upper layer of fermented milk or exopolysaccharide concentrate prepared from fermented milk significantly increased serum ceramide levels. X-ray diffraction analysis also showed addition of fermented milk or EPS concentrate to sphingomyelin eliminated the characteristic peak of sphingomyelin. This study demonstrated for the first time that co-ingestion of dietary sphingomyelin and fermented milk, compared with ingestion of dietary sphingomyelin alone, caused a significant increase in the absorption of sphingomyelin. Our results indicate exopolysaccharides in fermented milk may contribute to inhibition of sphingomyelin crystallization, resulting in enhanced absorption of dietary sphingomyelin in rats.
据报道，补充鞘磷脂可预防疾病并维持身体健康。然而，与甘油脂质相比，完整的鞘磷脂和神经酰胺的吸收较差。因此，如果能提高膳食鞘磷脂的生物利用度，那么在较低剂量下进行补充会更有效。本研究以大鼠为对象，旨在评估发酵乳对大鼠膳食鞘磷脂生物利用度的影响。大鼠禁食15小时后，经口给予测试溶液。在给药前以及给药后90、180、270和360分钟从尾静脉采集血样。与单独摄入鞘磷脂/乳磷脂浓缩物（MPL）相比，鞘磷脂/MPL与发酵乳共同摄入可使含有d16:1鞘氨醇以及16:0、22:0、23:0和24:0脂肪酸的血清神经酰胺显著增加约两倍，这些神经酰胺源自摄入的鞘磷脂。虽然脱脂乳也能提高这些神经酰胺的血清水平，但发酵乳的效果更佳。共同摄入发酵乳上层或由发酵乳制备的胞外多糖浓缩物可显著提高血清神经酰胺水平。X射线衍射分析还表明，向鞘磷脂中添加发酵乳或EPS浓缩物可消除鞘磷脂的特征峰。本研究首次证明，与单独摄入膳食鞘磷脂相比，膳食鞘磷脂与发酵乳共同摄入可显著提高鞘磷脂的吸收。我们的结果表明，发酵乳中的胞外多糖可能有助于抑制鞘磷脂结晶，从而增强大鼠对膳食鞘磷脂的吸收。
