Combined Treatment with Sardine Proteins and Citrus latifolia Extract Corrects Dyslipidemia, Prevents Lipid Peroxidation and Improves Lecithin: Cholesterol Acyltransferase and Paraoxonase 1 Activities in Hypercholesterolemic Rats

Aim: In this study, we determine the effects of the supplementation of sardine protein, Citrus latifolia extract and the combination of both on lecithin: cholesterol acyltransferase and paraoxonase-1 activities in hypercholesterolemic rats.
Place and Duration of Study: Laboratory of Clinical and Metabolic Nutrition, Department of Biology, Nature and life Sciences Faculty, University of Oran, Algeria, between February and September 2012.
Study Design: Forty male Wistar rats weighing 150-190 g were divided into 4 groups: Hypercholesterolemic (HC) fed a 20% casein diet enriched with cholesterol (1%), HC supplemented with sardine proteins (20%) (HC-Sp), HC supplemented with Citrus latifolia extract (1%) (HC-Ci) and HC supplemented with both Sp and Ci (HC-Sp+Ci), for 4 weeks.
Methodology: Serum and tissues lipid concentrations were estimated. High density lipoproteins (HDL2 and HDL3) were separated and their contents and composition in lipids and apolipoproteins were analyzed. Lecithin: Cholesterol Acyltransferase (LCAT) and paraoxonase 1 (PON 1) activities were determined.
Results: In the HC-Sp, HC-Ci and HC-Sp+Ci groups compared with the HC group, plasma, liver, kidney and aorta TC levels were reduced, whereas HDL-cholesterol was increased. In addition, plasma and HDL-TG concentrations were decreased. However, in tissues, TG contents were lower only in the HC-Sp+Ci group vs HC. HDL2, HDL3 and tissues lipid peroxidation levels were decreased in HC-Sp, HC-Ci and HC-Sp+Ci vs HC. In the hypercholesterolemic rats fed with Sp, Ci extract and Sp+Ci, LCAT activity was increased compared to HC group. Furthermore, PON 1 activity was elevated in HC-Ci and HC-Sp+Ci group vs HC.
Conclusion: In hypercholesterolemic rats, the supplementation with sardine protein, Citrus latifolia extract and the combination of both ameliorates tissues and plasma lipid profile and decreases lipid peroxidation in tissues and lipoproteins. Moreover, it improves reverse cholesterol transport by enhancing LCAT activity leading to anti-atherogenic effects. This effect is partially enhanced in HC-Ci and HC-Sp+Ci groups by a high PON 1 activity which protects lipoproteins from oxidation.