EFFECTS OF GARLIC POWDER AND SOY PROTEIN SUPPLEMENTATION ON BLOOD LIPID PROFILES AND AMINO ACID CONCENTRATIONS IN POSTMENOPAUSAL HYPERLIPIDEMIC MODEL RATS

摘要

High serum lipid levels such as total cholesterol, triglycerides and LDL-cholesterol have long been known as a risk factor for cardiovascular disease in many experimental animals and humans (Almario et al., 2001; Rowley et al., 2001). The major cause for hyperlipidemia has been associated with increasing age, sexual difference, obesity, inappropriate food intake, increased dietary fat intake, high blood pressure, high blood glucose, stress, smoking, and changes in hormonal and environmental factors (Kim et al., 2000; Rowley et al., 2001). Especially, it has been reported that the hyperlipidemia risk factor of postmenopausal women has increased due to changes in blood lipid metabolism and increased insulin resistance due to reduced synthesis of estrogens in the ovary (Kim et al., 2000; Seed, 2002). Numerous studies suggest that garlic and soy protein have antiatherosclerotic effects (Ali et al., 2000; Peleg et al., 2003; Satitvipawee et al, 2003). The use of aqueous garlic extract is known to be effective in reducing thromboxane formation by platelets both in vivo and in vitro (Satitvipawee et al., 2003). The antiatherogenic mechanisms of isoflavones are not known, but many studies suggest that soy protein may reduce the increased formation of atherosclerotic lesions in women after menopause (Isaacsohn et al., 1998). Recently, it has been also reported soy protein has beneficial effects on lipid changes, vascular reactivity and markers of inflammation in postmenopausal women (Lissin et al., 2004; Zhan and Ho, 2005). It is thought that the plasma lipid and free amino acid concentrations in postmenopausal women may be influenced by dietary garlic powder and soy protein supplementation.