著者
Koji Nagao Kazusa Nakamitsu Hiroki Ishida Kazuaki Yoshinaga Toshiharu Nagai Hoyo Mizobe Koichi Kojima Teruyoshi Yanagita Fumiaki Beppu Naohiro Gotoh
出版者
Japan Oil Chemists' Society
雑誌
Journal of Oleo Science (ISSN:13458957)
巻号頁・発行日
vol.63, no.10, pp.979-985, 2014 (Released:2014-10-01)
参考文献数
29
被引用文献数
22 23

The effects on lipid metabolism of four different n-3 highly unsaturated fatty acids (n-3HUFA) including eicosapentaenoic acid (EPA, 20:5n-3), docosapentaenoic acid (DPA, 22:5n-3), docosahexaenoic acid (DHA, 22:6n-3), and tetracosahexaenoic acid (THA, 24:6n-3) were compared in the HepG2 cell model. None of the n-3HUFAs affected the viability of the cells. THA exerted the strongest suppression on the synthesis of triacylglycerol and cholesteryl ester (ChE), and the order of the strength of suppression was found to be THA > DHA > DPA > EPA. The mRNA level of fatty acid synthase was suppressed by the n-3HUFAs and the order of the strength of suppression by n-3HUFAs was the same in both triacylglycerol and ChE synthesis. These findings support previous animal test results using EPA, DPA, and DHA. In conclusion, both the number of carbon atoms and double bonds in an n-3HUFA structure has an effect on lipid metabolism in HepG2 cells.
著者
Naohiro Gotoh Satoshi Kagiono Kazuaki Yoshinaga Hoyo Mizobe Toshiharu Nagai Akihiko Yoshida Fumiaki Beppu Koji Nagao
出版者
Japan Oil Chemists' Society
雑誌
Journal of Oleo Science (ISSN:13458957)
巻号頁・発行日
vol.67, no.3, pp.273-281, 2018 (Released:2018-03-01)
参考文献数
29
被引用文献数
5 19

The intake of trans fatty acids (TFAs) in foods changes the ratio of low density lipoprotein (LDL) to high density lipoprotein (HDL) cholesterol in blood, which causes cardiovascular disease. TFAs are formed by trans isomerization of unsaturated fatty acids (UFAs). The most recognized formation mechanisms of TFAs are hydrogenation of liquid oil to form partially hydrogenated oil (PHO,) and biohydrogenation of UFAs to form TFA in ruminants. Heating oil also forms TFAs; however, the mechanism of formation, and the TFA isomers formed have not been well investigated. In this study, the trans isomerization mechanism of unsaturated fatty acid formation by heating was examined using the model compounds oleic acid, trioleate, linoleic acid, and trilinoleate for liquid plant oil. The formation of TFAs was found to be suppressed by the addition of an antioxidant and argon gas. Furthermore, the quantity of formed TFAs correlated with the quantity of formed polymer in trioleate heated with air and oxygen. These results suggest that radical reactions form TFAs from UFAs by heating. Furthermore, trans isomerization by heating oleic acid and linoleic acid did not change the original double bond positions. Therefore, the distribution of TFA isomers formed was very simple. In contrast, the mixtures of TFA isomers formed from PHO and ruminant UFAs are complicated because migration of double bonds occurs during hydrogenation and biohydrogenation. These findings suggest that trans isomerization by heating is executed by a completely different mechanism than in hydrogenation and biohydrogenation.
著者
Naohiro Gotoh Kazuaki Yoshinaga Satoshi Kagiono Yukiko Katoh Yota Mizuno Fumiaki Beppu Toshiharu Nagai Hoyo Mizobe Akihiko Yoshida Koji Nagao
出版者
Japan Oil Chemists' Society
雑誌
Journal of Oleo Science (ISSN:13458957)
巻号頁・発行日
vol.68, no.2, pp.193-202, 2019 (Released:2019-02-01)
参考文献数
37
被引用文献数
4 11

Trans fatty acids (TFA) are considered risk factors for cardiovascular disease. However, detailed information on total content of TFA and TFA isomers and distribution of trans-octadecenoic acid positional isomers in foods consumed in Japan is not available till date. In this study, 250 foods, 169 processed foods and 81 foods derived from ruminant meat or milk, were analyzed. According to the results, most foods contained less than 1.0 g TFA / 100 g food. However, almost all foods containing butter had more than 1.0 g TFA / 100 g food. TFA isomers in foods were classified into two categories, monoene-rich type and polyenerich type. We hypothesized that these differences were attributed to diverse TFA formation mechanisms. Furthermore, we observed that trans-10-18:1 was also the dominant trans-18:1 positional isomer in foods consumed in Japan. These results are valuable for future analysis of the role of TFA in epidemiological studies in Japan.