首页 | 本学科首页   官方微博 | 高级检索  
     检索      


Dried and Fermented Powders of Edible Algae (Neopyropia yezoensis) Attenuate Hepatic Steatosis in Obese Mice
Authors:Koji Nagao  Nao Inoue  Keisuke Tsuge  Akira Oikawa  Tomoko Kayashima  Teruyoshi Yanagita
Institution:1.Department of Biological Resource Science, Saga University, 1 Honjo-machi, Saga 840-8502, Japan; (N.I.); (T.Y.);2.The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima 890-0065, Japan;3.Saga Regional Industry Support Center, Saga 849-0932, Japan;4.Graduate School of Agriculture, Kyoto University, Uji 611-0011, Japan;5.Faculty of Education, Saga University, 1 Honjo-machi, Saga 840-8502, Japan;
Abstract:Edible algae Neopyropia yezoensis is used as “Nori”, its dried sheet product, in Japanese cuisine. Its lipid components reportedly improve hepatic steatosis in obese db/db mice. In this study, we prepared “Nori powder (NP)” and “fermented Nori powder (FNP)” to utilize the functional lipids contained in “Nori” and examined their nutraceutical effects in vivo. Male db/db mice were fed a basal AIN-76 diet, a 10% NP-supplemented diet, or a 10% FNP-supplemented diet for 4 weeks. We detected eicosapentaenoic acid (EPA) present in both NP and FNP in the serum and liver of db/db mice in a dose-dependent manner. The NP diet reduced hepatic triglyceride accumulation (by 58%) in db/db mice by modulating gene expression, which resulted in the inhibition of lipogenic enzyme activity. Additionally, NP intake significantly suppressed the expression of inflammatory genes in the liver and hepatic injury marker levels in the sera (by 26%) of db/db mice. The FNP diet also led to a marked reduction in hepatic triglyceride accumulation (by 50%) and hepatic injury (by 28%) in db/db mice, and the mechanism of these alleviative actions was similar to that of the NP diet. Although the EPA content of FNP was one-third that of NP, metabolomic analysis revealed that bioactive betaine analogs, such as stachydrine, betaine, and carnitine, were detected only in FNP. In conclusion, we suggest that (1) mechanical processing of “Nori” makes its lipid components readily absorbable by the body to exert their lipid-lowering effects, and (2) fermentation of “Nori” produces anti-inflammatory molecules and lipid-lowering molecules, which together with the lipid components, can exert hepatic steatosis-alleviating effects.
Keywords:Neopyropia yezoensis  Koji fermentation  hepatic steatosis  obese db/db mouse  eicosapentaenoic acid  stachydrine  betaine  carnitine
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号