Premium
Polypeptide from 7S soy globulin alpha' subunit up‐regulates LDL‐receptors in HepG2 cells
Author(s) -
Lovati Maria Rosa,
Manzoni Cristina,
Pizzagalli Anna,
Castiglioni Silvia,
Duranti Marcello Maria
Publication year - 2008
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.22.1_supplement.303.7
Subject(s) - alpha (finance) , receptor , chemistry , ldl receptor , triglyceride , in vitro , protein subunit , in vivo , endocrinology , medicine , cholesterol , biochemistry , microbiology and biotechnology , biology , lipoprotein , construct validity , nursing , gene , patient satisfaction
7S soy globulin and its alpha’ subunit have been shown to positively modulate LDL receptor activity and to decrease triglyceride synthesis both in vitro and in vivo . The aim of the study was to evaluate the effect of a short chain of alpha’ (S‐alpha’) from 7S globulin, on cell cholesterol homeostasis. HepG2 cells were incubated in the presence/absence of alpha’ subunit (3.5.10 −6 M) or the S‐alpha’ at concentration of 10 −5 M and 10 −6 M. A dose‐dependent increase in up‐regulation of LDL‐receptors has been detected in cells exposed to S‐alpha’ vs that found in controls. Moreover, the 125 I‐LDL uptake (+ 192%) and degradation (+ 143%) of cells exposed to the highest dose of S‐alpha’ (8.10 −6 M) were similar to that found in cells incubated with 1 mM simvastatin; these results were confirmed by a dose‐dependent increase in the SREBP2 and LDL‐receptor mRNAs. Hep G2 cells exposed to S‐alpha’ for 24 h showed an increased uptake of fluorescent LDL vs both alpha’ and controls as detected by fluorescence microscopy: the fluorescence intensity was proportional to the amount of LDL uptaked by the cells as confirmed by FACS analysis. These findings open new prospects in the studies aimed at identifying the regulatory peptide/s from soybean proteins and the mechanism/s involved in this biological response, in view of their potential utilization in the management of human lipid disorders. Supported in part by a grant of MIUR of Italy.