![]() |
|
|
Food and Biodynamic Chemistry Laboratory, Graduate School of Life Science and Agriculture, Tohoku University, Sendai, 981-8555, Japan
1To whom correspondence should be addressed. E-mail: miyazawa{at}biochem.tohoku.ac.jp.
Both conjugated linoleic acid (CLA) and eicosapentaenoic acid (EPA) have an antitumor effect. Hence, we hypothesized that a combination of conjugated double bonds and an (n-3) highly unsaturated fatty acid would produce stronger bioactivity. To verify the antitumor effect of conjugated EPA (CEPA), we transplanted DLD-1 human colon tumor cells into nude mice, and compared the tumor growth between CEPA-fed mice and CLA- and EPA-fed mice. After tumor cell inoculation, mice were assigned to 1 of 4 groups (control, CLA, EPA, and CEPA) consisting of 10 mice each. The control group received only safflower oil fatty acids, whereas the remaining groups received a mixture of safflower oil fatty acids and 20 g/100 g of total fatty acids as CLA, EPA, or CEPA. Mice were fed once every 2 d for 4 wk at a dose of 50 mg/mouse at each feeding. After 4 wk, tumor growth in CEPA-fed mice was significantly suppressed, compared with that in CLA- (P < 0.005) and EPA-fed mice (P < 0.001). DNA fragmentation in the tumor tissues of the CEPA-fed mice occurred more frequently than in the CLA- (P < 0.001) and EPA-fed mice (P < 0.001), suggesting that CEPA induced apoptosis in the tumor tissues. To further investigate the mechanism, the level of oxidative stress in the tumor tissues was determined. The CEPA-fed mice showed significant lipid peroxidation, compared with the CLA- (P < 0.001) and EPA-fed mice (P < 0.001). Therefore, we verified that CEPA has a stronger in vivo antitumor effect than EPA and CLA, and that CEPA acts through induction of apoptosis via lipid peroxidation.
KEY WORDS: conjugated linoleic acid conjugated eicosapentaenoic acid nude mice lipid peroxidation conjugated fatty acid
This article has been cited by other articles:
![]() |
M. E. Grossmann, N. K. Mizuno, M. L. Dammen, T. Schuster, A. Ray, and M. P. Cleary Eleostearic Acid Inhibits Breast Cancer Proliferation by Means of an Oxidation-Dependent Mechanism Cancer Prevention Research, October 1, 2009; 2(10): 879 - 886. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Tsuzuki and Y. Kawakami Tumor angiogenesis suppression by {alpha}-eleostearic acid, a linolenic acid isomer with a conjugated triene system, via peroxisome proliferator-activated receptor {gamma} Carcinogenesis, April 1, 2008; 29(4): 797 - 806. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Tsuzuki, A. Shibata, Y. Kawakami, K. Nakagawa, and T. Miyazawa Conjugated Eicosapentaenoic Acid Inhibits Vascular Endothelial Growth Factor-Induced Angiogenesis by Suppressing the Migration of Human Umbilical Vein Endothelial Cells J. Nutr., March 1, 2007; 137(3): 641 - 646. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Tsuzuki, Y. Kawakami, R. Abe, K. Nakagawa, K. Koba, J. Imamura, T. Iwata, I. Ikeda, and T. Miyazawa Conjugated Linolenic Acid Is Slowly Absorbed in Rat Intestine, but Quickly Converted to Conjugated Linoleic Acid J. Nutr., August 1, 2006; 136(8): 2153 - 2159. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Tsuzuki, Y. Tokuyama, M. Igarashi, K. Nakagawa, Y. Ohsaki, M. Komai, and T. Miyazawa {alpha}-Eleostearic Acid (9Z11E13E-18:3) Is Quickly Converted to Conjugated Linoleic Acid (9Z11E-18:2) in Rats J. Nutr., October 1, 2004; 134(10): 2634 - 2639. [Abstract] [Full Text] [PDF] |
||||