Differential antioxidative and hypocholesterolemic responses to two fish protein hydrolysates (Sardina pilchardus and Boops boops) in cholesterol-fed rats

Abstract

Purpose

The purpose of this study was to evaluate the antioxidant and hypocholesterolemic activities of sardine and bogue protein hydrolysates in cholesterol-fed rats.

Design/methodology/approach

In total, 18 male Wistar rats (220 ± 10 g) fed 20 per cent casein, 1 per cent cholesterol and 0.5 per cent cholic acid were divided into three groups and received a daily gavage of 250 mg of sardine (SPH) or bogue (BPH) protein hydrolysates for 30 days. The third group, named control group (CG), received in the same conditions water. Lipoproteins were fractionated by size-exclusion fast protein liquid chromatography, and serum lipids, apolipoproteins and lipoproteins were assayed.

Findings

In SPH and BPH groups, serum total cholesterol concentrations were −66 per cent lower than in CG. This corresponded to the decreased very low-density lipoprotein-C in the former groups. Moreover, BPH treatment reduced low-density lipoprotein-C compared with CG and SPH groups. Compared with CG, serum phospholipids were reduced by SPH and BPH. Furthermore, BPH increased significantly APOA4 and sphingomyelin but lowered phosphatidylcholine. In the latter group, serum lecithin cholesterol acyltransferase activity was +23 per cent higher, but with SPH, this activity was −35 per cent reduced compared with CG. Apolipoprotein A-I contents were similar in the three groups. Compared with CG, hydroperoxide and lipid peroxidation contents in serum and lipoprotein fractions were reduced by SPH and BPH. Compared with CG, serum superoxide dismutase and glutathione peroxidase activities were increased in the treated groups, particularly in the BPH group.

Originality/value

These results suggest that sardine protein hydrolysates and particularly those of bogue could be a very useful natural compound to prevent hypercholesterolemia by both improving the lipid profile and modulating oxidative stress in cholesterol-fed rats.

Citation

Benomar, S., Yahia, S., Dehiba, F., Guillen, N., Rodriguez-Yoldi, M.J., Osada, J. and Boualga, A. (2015), "Differential antioxidative and hypocholesterolemic responses to two fish protein hydrolysates (Sardina pilchardus and Boops boops) in cholesterol-fed rats", Nutrition & Food Science, Vol. 45 No. 3, pp. 448-466. https://doi.org/10.1108/NFS-11-2014-0096