Hypolipidimic and antioxidant activities of virgin olive oil and its fractions in 2,4-diclorophenoxyacetic acid-treated rats

Abstract

Objective: We examined the effects of extra virgin olive oil (EVOO) and its hydrophilic and lipophilic fractions on serum lipids, oxidative stress, and morphologic and functional liver damages induced by 2,4-diclorophenoxyacetic acid (2,4-D).

Methods: Male Wistar rats were divided randomly into eight groups: control; 2,4-D at a dose of 5 mg/kg of body weight (2,4-D); 2,4-D plus EVOO (2,4-D/EVOO); 2,4-D plus the hydrophilic fraction (2,4-D/OOHF); 2,4-D plus the lipophilic fraction (2,4-D/OOLF); only EVOO (EVOO); only the hydrophilic fraction (OOHF); and only the lipophilic fraction (OOLF). These components were administered daily by gavage for 4 wk.

Results: A hepatic architecture aberration, increased activities of aspartate and alanine aminotransferase enzymes, total and low-density lipoprotein cholesterol, and malondialdehyde (MDA) level, and a decreased antioxidant defense system were observed in the 2,4-D group. The administration of EVOO restored the damage caused by 2,4-D by a significant decrease of plasma total and low-density lipoprotein levels and a moderate increase of high-density lipoprotein cholesterol. The 2,4-D/OOHF group exhibited a pronounced enhancement of the antioxidant defense system by an increase of superoxide dismutase, catalase, and glutathione peroxidase levels and a decrease of plasma and liver MDA levels. However, less improvement in the liver histoarchitecture and antioxidant status was observed in rats supplemented with OOLF diet, despite its richness in α-tocopherol.

Conclusion: Extra virgin olive oil may be a potential functional food source of antioxidants than can decrease the frequency of cardiovascular diseases and liver damage.