Hypocholesterolemic activity |
By screening using Caco-2 cells and animal studies, the serum and liver cholesterol levels were significantly lower in rats fed β-lactoglobuline tryptic hydrolysate (LTH) than in those fed casein tryptic hydrolysate (CTH). The peptide VYVEELKPTPEGDLEILLQK was purified from the Fraction 21 and 25, so this peptide was a potential hypocholesterolemic peptide (Synthetic peptide not determined).
The inhibition of micellar solubility of cholesterol which causes the suppression of cholesterol absorption by a direct interaction between cholesterol mixed micelles, and LTH in the jejunal epithelia is part of the mechanism underlying the hypocholesterolemic action of LTH.
Table 1. Effects of Oral Administration of Casein Tryptic Hydrolysate (CTH), β-Lactoglobulin Tryptic Hydrolysate (LTH), β-Sitosterol, or IIAEK on Body and Liver Weights, Food Intake, Serum HDL, and LDL + VLDL-cholesterol in Rats 1
| Group
| CTH
| LTH
| β-sitosterol
| IIAEK
| Body weight gain (g/4 days)
| 10.4 ± 0.4 a
| 10.5 ± 0.7 a
| 9.5 ± 0.8 a
| 8.7 ± 0.4 a
| Liver weight (g/100 g body weight)
| 5.22 ± 0.07 b
| 5.37 ± 0.05 a, b
| 5.17 ± 0.10 b
| 5.54 ± 0.11 a
| Food intake (day 3, g/day)
| 8.5 ± 0.2 a
| 8.7 ± 0.2 a
| 8.3 ± 0.3 a
| 8.4 ± 0.3 a
| Serum (mg/dl)
|
| Total cholesterol (a)
| 529.3 ± 14.4 a
| 441.3 ± 12.0 b
| 435.4 ± 12.8 b
| 328.7 ± 11.3 c
| HDL cholesterol (b)
| 42.6 ± 1.6 b
| 50.5 ± 2.4 a
| 52.1 ± 1.7 a
| 47.5 ± 0.8 a, b
| LDL + VLDL-cholesterol 2 | 486.7 ± 26.7 a
| 390.8 ± 22.9 b
| 383.3 ± 24.2 b
| 281.2 ± 20.6 c
| Atherogenic Index (b)/(a)
| 0.08 ± 0.01 c
| 0.11 ± 0.01 b
| 0.12 ± 0.01 b
| 0.15 ± 0.01 a
| 1 The data are means ± SEM (n = 7). Within a row, means with different superscript letters are significantly different (P < 0.05) by Duncan’s multiple range test. 2 Values were calculated as follows: LDL ± VLDL cholesterol = Total cholesterol — HDL cholesterol.
| | FIG 1. Effects of fractionated peptides derived from β-lactoglobulin on cholesterol absorption in Caco-2 cells in vitro.
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Specific target protein(s) |
N.D |