Soy proteins reduce progression of a focal lesion and lipoprotein oxidiability in rabbits fed a cholesterol-rich diet.
The effects of different dietary proteins on the progression of a focal atheromatous lesion and on lipoprotein oxidiability were studied in male New Zealand rabbits. Focal lesions were induced on common carotid arteries by applying an electric current, using a bipolar microcoagulator. After surgery, animals were fed for 90 days two different diets, both with 1% cholesterol, 15% saturated fatty acids and 20% protein: the protein source was constituted in one group (SOY) by 16% soy protein isolate plus 4% milk whey proteins, in the other (CASEIN) by 16% casein plus 4% milk whey proteins. Lower levels of plasma cholesterol and triglycerides (-47 and -65%, respectively) (P < 0.05) were detected in the SOY versus the CASEIN group at the end of treatment. Cryosection analyses of the carotids, indicated a highly significant reduction (-39%; P < 0.05) in the focal lesion progression in the SOY versus the CASEIN group. Copper-mediated oxidation of low-density lipoprotein (LDL) from rabbits fed the two different diets, performed in vitro by analysis of conjugated diene formation, showed a significantly longer lag phase in the SOY (150 +/- 5 min) versus the CASEIN animals (20 +/- 3 min) (P < 0.05). These data, while confirming the well-known lipid lowering properties of soy proteins, indicate, in this animal model, a remarkable activity on a focal atheromatous lesion, possibly also linked to a powerful antioxidant activity.
Castiglioni
Silvia
S
Department of Pharmacological Sciences, University of Milano, Via Balzaretti 9, 20133, Milan, Italy.
Manzoni
Cristina
C
D'Uva
Antonio
A
Spiezie
Rossella
R
Monteggia
Elena
E
Chiesa
Giulia
G
Sirtori
Cesare R
CR
Lovati
Maria R
MR
D000704:Analysis of Variance; D000818:Animals; D001161:Arteriosclerosis / Q000178:diet therapy* / Q000517:prevention & control; D001707:Biopsy, Needle; D001835:Body Weight; D002339:Carotid Arteries / Q000473:pathology*; D002784:Cholesterol / Q000032:analysis; D002791:Cholesterol, Dietary; D004044:Dietary Proteins / Q000008:administration & dosage*; D004195:Disease Models, Animal; D018450:Disease Progression; D004730:Endothelium, Vascular / Q000473:pathology; D007150:Immunohistochemistry; D015227:Lipid Peroxidation; D008297:Male; D014674:Plant Proteins, Dietary / Q000494:pharmacology*; D011336:Probability; D011817:Rabbits; D012680:Sensitivity and Specificity; D030262:Soybean Proteins / Q000494:pharmacology*; D014280:Triglycerides / Q000032:analysis
D002791:Cholesterol, Dietary; D004044:Dietary Proteins; D014674:Plant Proteins, Dietary; D030262:Soybean Proteins; D014280:Triglycerides; D002784:Cholesterol