Effects of olive oil and its minor phenolic constituents on obesity-induced cardiac metabolic changes.
BACKGROUND
Olive oil and its minor constituents have been recommended as important dietary therapeutic interventions in preventive medicine. However, a question remains to be addressed: what are the effects of olive oil and its phenolic compounds on obesity-induced cardiac metabolic changes?


METHODS
Male Wistar rats were divided into two groups (n = 24/group): (C) receiving standard-chow; (Ob) receiving hypercaloric-chow. After 21 days C and Ob groups were divided into four subgroups (n = 6/group):(C) standard-chow and saline; (C-Olive)standard-chow and olive-oil (3.0 g/kg.day); (C-Oleuropein)standard-chow and oleuropein (0.023 mg/kg/day); (C-Cafeic) standard-chow and cafeic-acid (2.66 mg/kg/day); (Ob)receiving hypercaloric-chow and saline;(Ob-Olive) hypercaloric-chow and olive-oil;(Ob-Oleuropein) hypercaloric-chow and oleuropein;(Ob-Cafeic) hypercaloric-chow and cafeic-acid. Treatments were given twice a week during 21 days.


RESULTS
After 42 days, obesity was evidenced in Ob rats from enhanced body-weight, surface-area, and body-mass-index. Energy-expenditure, oxygen consumption(VO2) and fat-oxidation were lower in Ob-group than in C. Despite no morphometric changes, Ob-Olive, Ob-Oleuropein and Ob-Cafeic groups had higher VO2, fat-oxidation, myocardial beta-hydroxyacyl coenzyme-A dehydrogenase and lower respiratory-quotient than Ob. Citrate-synthase was highest in Ob-Olive group. Myocardial lipid-hydroperoxide(LH) and antioxidant enzymes were unaffected by olive-oil and its compounds in obesity condition, whereas LH was lower and total-antioxidant-substances were higher in C-Olive and C-Oleuropein than in C.


CONCLUSIONS
The present study demonstrated for the first time that olive-oil, oleuropein and cafeic-acid enhanced fat-oxidation and optimized cardiac energy metabolism in obesity conditions. Olive oil and its phenolic compounds improved myocardial oxidative stress in standard-fed conditions.
Department of Chemistry and Biochemistry, Institute of Biological Sciences, São Paulo State University, UNESP, 18618-000 Botucatu, São Paulo, Brazil.
Geovana M X
GM
Ebaid
Fábio R F
FR
Seiva
Katiucha K H R
KK
Rocha
Gisele A
GA
Souza
Ethel L B
EL
Novelli
D015094:3-Hydroxyacyl CoA Dehydrogenases / Q000378:metabolism; D000818:Animals; D002109:Caffeic Acids / Q000494:pharmacology*; D002151:Calorimetry; D002950:Citrate (si)-Synthase / Q000378:metabolism; D057888:Iridoid Glucosides; D039823:Iridoids; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D009765:Obesity / Q000378:metabolism* / Q000503:physiopathology; D000069463:Olive Oil; D010636:Phenols / Q000494:pharmacology; D010938:Plant Oils / Q000494:pharmacology*; D011714:Pyrans / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D002109:Caffeic Acids; D057888:Iridoid Glucosides; D039823:Iridoids; D000069463:Olive Oil; D010636:Phenols; D010938:Plant Oils; D011714:Pyrans; C002769:oleuropein; D015094:3-Hydroxyacyl CoA Dehydrogenases; D002950:Citrate (si)-Synthase; C040048:caffeic acid