Soybean protein diet increases low density lipoprotein receptor activity in mononuclear cells from hypercholesterolemic patients.

Abstract

The effect of two diets containing different protein sources (animal vs. soybean) on the low density lipoprotein (LDL) receptor activity was tested in freshly isolated mononuclear cells from 12 individuals with severe type II hyperlipoproteinemia. The two diets, both taken for 4 wk in a crossover design were of otherwise identical composition. During the soybean protein diet period, total cholesterol was reduced by 15.9% and LDLcholesterol by 16.4%. The diet containing animal proteins exerted no significant change in plasma lipid levels vs. the baseline findings. The soybean diet regimen dramatically affected the degradation of LDL by mononuclear cells. Degradation was increased 16-fold vs. the basal activity and 8-fold compared with the standard low lipid diet with animal proteins. There was, however, no clear relationship between the reduction of total and LDL-cholesterolemia and the increased LDL degradation. These findings confirm similar data previously obtained in cholesterol-fed rats and suggest that some factor/s, most likely of a protein nature, may regulate the expression of lipoprotein receptors in peripheral cells, particularly when receptor activity is suppressed by experimental diets and/or spontaneous hypercholesterolemia.

A biochanin-enriched isoflavone from red clover lowers LDL cholesterol in men

“…Indeed, the controversy over the need to have isoflavones retained within soy protein is not resolved. However, there is a suggestion that isoflavones, like oestrogens, may upregulate the LDL receptors (Lovati et al, 1987;Baum et al, 1998) and thereby accelerate clearance of LDL-C from the circulation. If that requires interaction with oestrogen receptors in liver and other tissues, then biochanin/genistein might be expected to exert a greater effect than formononetin/ daidzein.…”

Function of Traditional Foods and Food Culture in China

“…The lower sulfur amino acid content of soy protein may help to reduce calcium excretion in comparison to consuming animal proteins, so it lowers the risk of osteoporosis. Intake of soy protein can decrease cholesterol level of serum, so the soy protein can help to reduce the risk of kidney disease and heart disease in high risk individuals 15 . The contents of vitamin B 12 , which is essential for the nervous system, in Chou sufu (strong smell sufu) and red sufu produced in Beijing were determined.…”

Effect of genistein on cholesterol metabolism-related genes in a colon cancer cell line

“…Genistein has been also shown to decrease cholesterol synthesis in cultured HepG2 [7] and inhibits HMG-CoA reductase activity in MCF-7 human breast cancer cells [17]. It has been suggested that the soy proteins enhance the expression of the LDL receptor in cultured human hepatoma cells [26], animals, and hypercholesterolemic Type 2 diabetic patients [24,25]. A similar effect has been observed with a soy protein polypeptide in cultured HepG2 cells [27].…”