No abstract

To know whether isoflavones are responsible for the hypocholesterolemic effect of soy protein, the effect on plasma cholesterol of isoflavone-free soy protein prepared by column chromatography was examined in rats. Five-week-old male Sprague-Dawley rats were fed cholesterol-enriched AIN-93G diets containing either 20% casein (CAS), 20% soy protein isolate (SPI), 20% isoflavone-free SPI (IF-SPI), 19.7% IF-SPI + 0.3% isoflavone-rich fraction (isoflavone concentrate, IC), or 20% CAS + 0.3% IC for 2 weeks. Plasma total cholesterol concentrations of rats fed SPI and IF-SPI were comparable and were significantly lower than that of rats fed CAS. The addition of IC to the CAS and IF-SPI did not influence plasma cholesterol level. Fecal steroid excretion of the three SPI groups was higher than that of the two CAS groups, whereas the addition of IC showed no effect. Thus, a significant fraction of the cholesterol-lowering effect of SPI in rats can be attributed to the protein content, but the isoflavones and other minor constituents may also play a role.

No abstract

No abstract

Background: Mung bean is well known as a starch source, but the physiological effects of mung bean protein have received little attention. In this study, we isolated mung bean protein from de-starched mung bean solutions, and investigated its influence on lipid metabolism. Objective: The aim of this study is to clarify the influence of the lipid metabolism by consumption of mung bean protein isolate (MPI)Methods: Diets containing either mung bean protein isolate (MPI) or casein were fed to normal rats for 28 days.Results: Both groups ate the same amount of food, but the plasma triglyceride level, relative liver weight and liver lipid contents (cholesterol and triglyceride pool) in the MPI group were significantly lower than in the casein group. In the MPI group, the expression of sterol regulatory-element binding factor 1 (SREBF1) mRNA in the liver was significantly different when compared with the casein group. The significantly lower levels of insulin and free fatty acids in the MPI-fed rats may be due to the regulation of genes related to lipid metabolism in the liver.Conclusions: These results suggest that MPI may improve the plasma lipid profile by normalizing insulin sensitivity.Keywords: mung bean, Vigna radiata L., 8S globulin, triglyceride, β-conglycinin, 7S globulin, insulin sensitivity, SREBF1

IntroductionThe metabolic syndrome is known to increase cardiovascular morbidity and mortality, and central obesity is the key component of its development 1 3 . Although the pathogenesis of metabolic syndrome is complicated, lipid abnormality is proposed as a feature of metabolic syndrome 1 3 . Many studies suggested that plant proteins could be important modulators of the risks associated with this syndrome 4, 5 . For example, several studies have shown that dietary soy protein reduces cholesterol and triglyceride TG levels in animals and humans 4 8 . Moreover soy β-conglycinin βCG , a soybean storage protein, has been reported to exert physiological effects such as promoting lipid lowering effects and preventing obesity in several animal models 9 13 . However, physiological functions of βCG in non-high-fat or non-high-cholesterol diet-fed rodents have not been fully evalutated, and almost all of previous studies have been conducted with diets in which all dietary protein was replaced by βCG even though its es-

No abstract

IntroductionWith recent lifestyle changes, an increase in the prevalence of metabolic syndromes, such as obesity, hyperlipidemia, and diabetes, has become a societal issue. Obesity is a risk factor for the onset of various metabolic diseases 1,2) . The International Diabetes Federation reported that the number of diabetes cases has increased to 536.6 million by 2021 3) . Therefore, the World Health Organization (WHO) recommends a healthy diet to prevent type II diabetes mellitus 4) .