title: Proteins of white lupin seed, a naturally isoflavone-poor legume, reduce cholesterolemia in rats and increase LDL receptor activity in HepG2 cells.
abstract: White lupin (Lupinus albus, L.), a widely cultivated crop that has been consumed for many years in Western Europe, may provide a useful alternative for individuals wishing to substitute animal with plant proteins for cardiovascular disease prevention. Lupin seeds have a very low content of isoflavones, and lupin protein isolates are essentially isoflavone free. In rats fed a casein-based cholesterol + cholic acid diet, a relatively low daily intake (50 mg/d by gavage for 2 wk) of total lupin protein extract reduced plasma total and VLDL + LDL cholesterol concentrations by 21 and 30%, respectively (both P<0.001). In an attempt to elucidate the lipid-lowering mechanism, LDL receptor activity was evaluated in a human hepatoma cell line (HepG2). In this model, the lupin total protein extract was essentially inactive, whereas one purified minor protein component, conglutin gamma, had a remarkable upregulatory effect, with maximal increases of 53 and 21% (both P<0.05) for LDL uptake and degradation, respectively. This initial study indicates that lupin, although isoflavone free, has hypocholesterolemic activity similar to that of other leguminous proteins in an established animal model. Further, the cholesterol reduction appears to be associated with stimulation of LDL receptors by a well-defined protein component of the lupin seeds as demonstrated by in vitro studies.
authors.affiliation: Department of Pharmacological Sciences, University of Milano, 20133 Milan, Italy. cesare.sirtori@unimi.it
authors.forename: Cesare R
authors.initials: CR
authors.lastname: Sirtori
authors.forename: Maria Rosa
authors.initials: MR
authors.lastname: Lovati
authors.forename: Cristina
authors.initials: C
authors.lastname: Manzoni
authors.forename: Silvia
authors.initials: S
authors.lastname: Castiglioni
authors.forename: Marcello
authors.initials: M
authors.lastname: Duranti
authors.forename: Chiara
authors.initials: C
authors.lastname: Magni
authors.forename: Sheila
authors.initials: S
authors.lastname: Morandi
authors.forename: Alessandra
authors.initials: A
authors.lastname: D'Agostina
authors.forename: Anna
authors.initials: A
authors.lastname: Arnoldi
mesh_terms: D000818:Animals; D000924:Anticholesteremic Agents / Q000494:pharmacology*; D006528:Carcinoma, Hepatocellular; D002364:Caseins / Q000008:administration & dosage; D002784:Cholesterol / Q000097:blood*; D002791:Cholesterol, Dietary / Q000008:administration & dosage; D019826:Cholic Acid / Q000008:administration & dosage; D006937:Hypercholesterolemia / Q000209:etiology; D007529:Isoflavones / Q000032:analysis; D008099:Liver / Q000737:chemistry*; D008113:Liver Neoplasms; D031297:Lupinus / Q000737:chemistry*; D008297:Male; D010936:Plant Extracts / Q000008:administration & dosage*; D010940:Plant Proteins / Q000008:administration & dosage*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011973:Receptors, LDL / Q000032:analysis*; D012639:Seeds / Q000737:chemistry*; D014407:Tumor Cells, Cultured
chemical_list: D000924:Anticholesteremic Agents; D002364:Caseins; D002791:Cholesterol, Dietary; D007529:Isoflavones; D010936:Plant Extracts; D010940:Plant Proteins; D011973:Receptors, LDL; D002784:Cholesterol; D019826:Cholic Acid