• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.4
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• pp.401-407
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• 1991

Anticarcinogenic conjugated dienoic derivatives of linoleic acid (CLA) is present in grilled beef, cheese, and related foods, CLA is generated via isomerization of linoleic acid in the cow's rumen by anaerobic bacteria and food proceessing as well. Another source of CLA is its endogenous generation via the carbon centered free radical oxdation of linoleic acid. We propose that the formation and generation of CLA in vivo represents a previously unrecognized in situ "defense mechanism" against membrane attack by oxygen free radicals. The cis, 9-trans, 11 CLS isomer is selectively incorporated into cellular phospholipid, which exhibits a potent antioxidant, reduces the activation of 2-amino-3-methylimidazo, [4,5-f] quinoline (IQ) for baxterial mutagenesis, and inhibits ornithine decarboxylase(ODC) activity induced by 12-0-tetradecanoylphorbol-13-acetate (TPA). We believe that at least these biological activities of CLA explain the anticarcinogenic activity of CLA.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.972-977
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• 1997

Conjugated dienoic derivatives of linoleic acid(CLA) are a series of positional and gemotric isomers of linoleic acid which are found naturally in food, mainly dietary products and breef. We studied the effects of CLA on the growth of tumor cells and the production of interleukin-1(IL-1) and interleukin-2(IL-2). CLA treatment markedly inhibited the growth of Yac-1 cells and sarcoma-180 cells by 99 and 82% to that of control, respectively, after four days of incubation at 37$^{\circ}C$. To elucidate the immunological mechanism of antitumor activity of CLA, spleen cells of Balb/c mouse were exposed to 31, 63, 125, 250 $\mu\textrm{g}$ of CLA per ml for 24 hrs at 37$^{\circ}C$. The culture supernatants of CLA-exposed spleen cells reduced the production of IL-1 and IL-2 in all of the test conditions. These results indicate that the anticarcino-genic effect of CLA was mediated by the other actions rather than the production of the Il-1 or IL-2. We suggest that CLA might have an antiinflammatory effect in part due to its inhibitory action on the production of IL-1.

• Journal of Nutrition and Health
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• v.30 no.4
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• pp.442-450
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• 1997

Conjugated dienoic derivatives of linoleic acid(CLA) are a mixture of positional and geometric isomers of linoleic acid(LA). We previously found that CLA changes the fatty acid profile in chicken eggs and serum by decreasing monounsaturated fatty acids. Studies were conducted to explore the effects of CLA on fatty acid composition. Rabbits were fed a semisynthetic diet with or without CLA(0.5g CLA/rabbit/day) for 22 weeks. Compared to the control, rabbits fed CLA had significantly lower monounsaturated fatty acid levels(palmitoleic acid Cl6 : 1 by 50% and oleic acid Cl8 : 1, by 20%) in plasma lipids. We found similar differences in fatty acid composition in the liver and the aorta. The inhibitory effect of CLA on $\Delta$9 desaturation was confirmed in a human hepatoma cell line, Hep G2. CLA significantly decreased $\Delta$9 desaturation in 4-5 hours as shown by an increase in the ratio of Cl6 : 0 to C 16 1, This is apparently due to a decrease in $\Delta$9 desaturase(stearoyl-CoA desaturase, SCD) activity ; it was decreased more than 50%. These results, along with our previous findings, indicate that CLA is an inhibitor of $\Delta$9 desaturase in the liver.

• Food Science of Animal Resources
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• v.36 no.2
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• pp.170-177
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• 2016

Conjugated linoleic acid (CLA) is a group of positional and geometric isomers of conjugated dienoic derivatives of linoleic acid. CLA has been reported to be able to reduce body fat. In this study, we investigated the antidiabetic effect of fermented milk (FM) containing CLA on type II diabetes db/db mice. Mice were treated with 0.2% low FM, 0.6% high FM, or Glimepiride (GLM) for 6 wk. Our results revealed that the body weight and the levels of fasting blood glucose, serum insulin, and leptin were significantly decreased in FM fed mice compared to db/db mice. Oral glucose tolerance and insulin tolerance were significantly ameliorated in FM fed mice compared to db/db mice. Consistent with these results, the concentrations of serum total cholesterol, triglycerides, and LDL cholesterol were also significantly decreased in FM fed mice compared to db/db mice. However, the concentration of HDL cholesterol was significantly higher in FM fed mice compared to db/db mice. These results were similar to those of GLM, a commercial anti-diabetic drug. Therefore, our results suggest that FM has anti-diabetic effect as a functional food to treat type II diabetes mellitus.