Cholesterol-lowering effects of dietary blue lupin (Lupinus angustifolius L.) in intact and ileorectal anastomosed pigs

Abstract

The present study was undertaken to investigate the effect of cholesterol-enriched casein (CAS) and blue lupin seed (BL) diets on the cholesterol metabolism of intact (INT) and ileorectal anastomosed (IRA) pigs. For 3 weeks, four groups of six pigs were allocated to the treatments (CAS-INT, CAS-IRA, BL-INT, and BL-IRA). Diet-induced hypercholesterolemia was inhibited by the BL through a substantial decrease in plasma LDL-cholesterol. The BL also reduced liver esterified and total cholesterol, increased hepatic LDL receptor synthesis and HMG-CoA reductase activity, and stimulated intestinal bile acid reabsorption. The neutral sterol output was higher in BL-than in CAS-fed pigs. The bile acid output was lower in IRA than in INT pigs. Surgery also prevented steroid microbial transformation, but it did not influence plasma cholesterol levels. These results suggest that the hypocholesterolemic effect of the BL, compared with the CAS, is attributable to impaired intestinal cholesterol absorption, probably involving increased bile acid reabsorption and higher contents of dietary phytosterols, both factors that reduce the micellar solubilization of cholesterol. Furthermore, according to our data, the contribution of the large intestine to cholesterol metabolism is very weak. Hypercholesterolemia and its implications for cardiovascular diseases is a major problem in human health, and much attention has been paid to dietary intervention as a tool for its prevention and treatment (1). Legumes have shown hypocholesterolemic effects in human and animal models (2-4), but these studies have mainly been done with soybean or its components. Therefore, studies involving other legumes, such as lupins, may clarify the mechanism by which plasma cholesterol is reduced and lead to the identification of new functional foods and/or components.Seeds of several species of lupins have been used as food for Ͼ 3,000 years in the Mediterranean area (5). These bitter seeds had to be soaked in water before consumption, to remove most of their alkaloid content (6). From the second half of the 20th century onward, low-alkaloid varieties of white lupin ( Lupinus albus ), yellow lupin ( Lupinus luteus ), and blue lupin ( Lupinus angustifolius ) have been domesticated and selected (7). In 2004, sweet varieties of these three species were mainly cultivated in several parts of Australia, Europe, and South America (8) and used for feed and food applications. Blue lupin seeds have higher nonstarch polysaccharide (6) and protein contents than soybean, with a similar amino acid profile (9). Their use in the food industry is being developed, and lupins are beginning to replace soybean in products such as tempe, miso, fermented sauces, and cooked snack foods (6). Lupin-based fiber supplements, cookies, bread, and spaghetti, with a high sensory quality, are also reported (10).No studies have been undertaken to test the effect of blue lupin seeds on cholesterol metabolism in the pig, an animal model with a plasma lipid profile similar to that of huma...

The health benefits of sweet lupin seed flours and isolated proteins

“…Another model applied to narrow-leaf lupin was the hyperlipidaemic pig, initially in 2005 (Martins, Riottot, de Abreu, Viegas-Crespo, Lança, Almeida, et al, 2005) and then again in 2014 (Radtke, Geissler, Schutkowski, Brandsch, Kluge, Duranti, et al, 2014). In both researches, significant decreases of total and LDL-cholesterol were observed: in the former the changes in total cholesterol and LDL-C were -29.2% and -37.9%, respectively, in the latter the changes were -32.6% and -28.9%, respectively.…”

Effects of increasing dietary protein and fibre intake with lupin on body weight and composition and blood lipids in overweight men and women

“…20,21 In addition, results obtained from several animal studies suggest cholesterol-lowering effects of lupin. Cholesterol lowering has been observed in chickens 22 and pigs 23 fed whole lupin grain. Other data suggest that protein and fibre isolates from lupin may improve serum lipids.…”

Effects of lupin-enriched foods on body composition and cardiovascular disease risk factors: a 12-month randomized controlled weight loss trial

“…[14][15][16]22 Limited data from human and animal studies suggest that a lupin-enriched diet may benefit serum lipids and lipoprotein. 24,49 However, we previously showed that an ad libitum lupin flour-enriched diet over 4 months also had no benefit on the serum lipid profile. 11 The lack of effect on blood lipids in our studies may be because of a number of factors.…”

“…20,21 In a previous 16-week trial, we showed that consumption of lupin flour-enriched bread reduced 24-h systolic blood pressure by 3.0 mm Hg. 22 Lupin-enriched diets have also been shown to reduce blood cholesterol concentrations in animals [23][24][25] and humans. 26 Furthermore, acute reductions in postprandial glucose and insulin have been demonstrated with lupin flour-enriched bread consumption, 12,27 but longer-term effects are not clear.…”