SOYBEAN AND HEALTH - University of Macau Library

136Soybean and HealthCarta et al. (2002) concluded that a regular intake of CLA and or TVA as its precursor shouldwork as an excellent preventive agent that would modulates lipid metabolism. Kathirvelan(2007) found that feeding CLA ghee (20 % in the diet) to male wistar rats doesn’t increasethe body weight as compared to the control group (Table 14)weekSoybean oil diet(Control)Average weekly body weight (gram)Low CLA gheedietHigh CLA gheediet0 131.13 4.70 125.00 2.85 128.57 3.452 169.29 5.09 165.01 4.03 163.14 4.684 187.86 6.04 185.08 6.22 185.71 7.026 203.57 3.45 198.52 5.59 195.29 4.178 215.00 5.34 214.29 7.58 212.86 4.9310 231.69 8.55 228.33 7.42 227.51 6.9512 243.33 7.42 240.00 6.35 239.17 4.4714 254.00 5.88 257.50 8.14 252.51 6.3216 263.33 4.81 265.00 6.67 262.12 4.21Over all mean 211.02 13.51 208.8114.23 207.43 13.73Values are Mean SE for n=8Table 14. Average weekly body weight of rats fed on CLA enriched ghee dietStudies in rats and mice have shown that feeding CLA at the level of 0.5% in total dietproduced small reduction in body fat gain in growing animals (Pariza et al., 1997; Park et al.,1997). Whilst the actions of CLA in inhibiting body fat accumulation have receivedconsiderable attention because of increasing concern for marked increases in obesity inwestern societies, care should be taken in extrapolating these findings to man until moreinformation is available. The specific mechanism by which dietary CLA reduces body fatcontent is likely to vary from one animal species to another. The results of animal studies arealso not conclusive. The mechanism by which CLA alters lipid metabolism and bodycomposition in animals is not fully elucidated. It may be tissue and species-specific. Inrodents, CLA-induced alteration of lipid metabolism appears to involve increase in rates oflipolysis and fatty acid oxidation. Support for this mechanism comes from the observationof increased hormone sensitive lipase activity and enhanced carnitine palmitoyl transferaseactivity in several tissues of mice fed CLA (Pariza et al., 2003).Peroxisome proliferators activated receptor alpha (PPAR), one of the nuclear receptorsrelated to the modulation of environmental and dietary stimuli (Schoonjan et al., 1996), islikely to be involved in the regulation of the gene expression of fatty acid beta oxidationenzymes by dietary CLA. It has been demonstrated that CLA is a potent legend andactivator of PPAR (Belury et al., 1997) but Peterson et al. (2003) observed that a mixture ofCLA isomers increased the gene expression of hepatic fatty acid beta oxidation enzymesthrough both PPAR dependent and independent mechanisms. The activity of fatty acid