Lipid conjugates animals

The accumulation of different CLA isomers in various tissues was also reported. When diets containing 1% of either cis, trans or trans, trans CLA isomers were fed to rats, conjugated dienes did not accumulate in testis or brain lipid. By contrast, CLA was incorporated into adipose tissue (26). Substantial deposition of conjugated dienes occurred in heart lipid when animals were fed cis, trans isomers, but no increase was observed when animals were fed trans, trans CLA isomers. 

This group of sugar-lipid conjugates is not limited to organs of animals. For example, similar compounds are found in mushrooms and plant seeds.7... 

Aharoni, Y., Orlov, A., Brosh, A. (2004). Effects of high-forage content and oilseed supplementation of fattening diets on conjugated linoleic acid (CLA) and trans fatty acids profiles of beef lipid fractions. Animal Feed Science and Technology, 117, 43-60. 

There is some support for a role for free radicals in the pathogenesis of ischaemic colitis from animal studies. Murthy and Qi (1992) used a spin trap to demonstrate increased production of free radicals up to 60 min after reperfusion, whereas Douglas etal. (1989) demonstrated increases in malondialdehyde and conjugated dienes (presumptive measures of lipid peroxidation) in a rat model of ischaemic colitis. There is no data relating to human ischaemic colitis. 

DEHP effects on the peroxisomal system of the liver appeared to be increased in rats kept on a choline deficient diet (Perera et al. 1986). This conclusion was based on an increase in the conjugated dienes in the microsomes of choline-deficient animals exposed to 500 mg/kg DEHP for 4 weeks. Conjugated dienes are indicators of free radical oxygen modification of cellular lipids. 

Although the marine animals have been exploited thoroughly for food and other byproducts, their plant counter parts have not been exploited for food to the same extent, barring some seaweeds like Porphyra (nori) and Laminaria (konbu). Unlike terrestrial counter parts, marine plants have not been looked upon as important substrates for further processing of their lipids. In this section, seaweed lipids have been classified for convenience into different categories, viz., general fatty acids, conjugated fatty acids, carotenoids (fuco-xanthin), and sterols (fucosterol). 

There are few reports on the inhibitory effect of conjugated polyenes on the growth of cancer cell lines. Begin et al. (1988) reported the toxic effect of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on several kinds of tumor cells other polyunsaturated fatty acids, i.e., arachidonic acid (22 4n-6), a-linolenic acid (18 3n-3), and y-linolenic acid (18 3n-6) have cytotoxic action on several tumor cell lines at concentrations above 50 pM. Further, Tsuzuki et al. (2004) demonstrated that the anticarcinogenic effect of CLN are directly associated with lipid peroxidation. They transplanted human colon cancer cells (DLD-1) into nude mice, and CLA (9c, lit and lOt, 12c-18 2) and CLN (9c, lit, 13t-18 3) were administered to animals. Tumor growth was suppressed by the supplementation of CLA and CLN, and the extent of suppression was CLN >9c, llt-CLA.>10t, 12c-CLA, in that order. Furthermore, DNA fragmentation was enhanced and lipid peroxidation increased in tumor cells of the CLN-fed mouse. Thus this study indicates the possibility of seaweeds as potential sources of anticancer substances. 

Kelley, D.S. and Erickson, K.L. 2003. Modulation of body composition and immune cell functions by conjugated linoleic acid in humans and animal models Benefits vs. risks. Lipids 38, 377-386. 

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