(Circulation. 2000;102:2169.)
© 2000 American Heart Association, Inc.
Brief Rapid Communications |
From the University of Milan, Institute of Pharmacological Sciences, Milan, Italy.
Correspondence to Francesco Visioli, PhD, Institute of Pharmacological Sciences, Via Balzaretti 9, 20133 Milan, Italy. E-mail francesco.visioli{at}unimi.it
| Abstract |
|---|
|
|
|---|
(iPF2
-III).
Methods and ResultsAn OMWW extract (5 mg/kg, providing 414
µg/kg of hydroxytyrosol) was administered to rats daily for 4 days,
during which time the animals were exposed to sidestream smoke for 20
minutes once a day. Daily urines were collected, and the urinary
excretion of 8-iso-PGF2
was evaluated as an index of
oxidative stressinduced in vivo lipid peroxidation. The exposure of
rats to passive smoking increased the urinary excretion of
8-iso-PGF2
by 44±4.2% at 48 hours and by 55±10% at
96 hours. Treatment with the OMWW extract was able to completely
prevent the increase at 48 hours and resulted in lower increments
(34±18% versus 55±10%) of 8-iso-PGF2
excretion at
96 hours.
ConclusionsA low dose of hydroxytyrosol, administered through OMWW, reduces the consequences of sidestream smokeinduced oxidative stress in rats.
Key Words: hydroxytyrosol isoprostanes atherosclerosis smoking lipids
| Introduction |
|---|
|
|
|---|
isomers
that is produced from arachidonic acid via free
radicalcatalyzed mechanisms) are thought to be reflective of enhanced
oxidative stress.3 In the Mediterranean area, where the diet is rich in fruits and vegetables and where olive oil is the principal source of fat, the incidence of coronary heart disease is lowest.4 Olive oil is obtained by pressing of the olive fruit, which contains a variety of "minor constituents," most of which are phenolic in nature, that give extra virgin olive oil its particular taste. Such compounds, eg, hydroxytyrosol, have been shown to possess interesting biological activities in vitro.5 During olive oil production, large volumes of water are generated and subsequently discarded; this "waste water" contains notable amounts of relatively polar phenolic compounds, including hydroxytyrosol, whose antioxidant activities have been thoroughly investigated.5 6
Cigarette smoke induces oxidative stress, as reflected by increased circulating levels and urinary excretion of F2-isoprostanes.7 It is noteworthy that passive smoking also increases the risk of heart disease and that experimental evidence indicates that it significantly impairs endothelial function and accelerates atherosclerosis in animals.8 9 It is conceivable that some of the noxious effects of second-hand smoke are due to an enhanced cellular exposure to reactive oxygen species, leading to the formation of lipid peroxidation products, such as isoprostanes, for which various deleterious biological activities have been proposed.3
The present study sought to investigate the effects of an olive
mill waste water (OMWW) preparation, of which hydroxytyrosol was
the only bioactive component, on the urinary excretion of
8-iso-PGF2
(iPF2
-III) in rats exposed to
sidestream smoke.
| Methods |
|---|
|
|
|---|
OMWW extracts were prepared from freshly picked olives as previously described.6 High-performance liquid chromatographic analysis6 revealed that the OMWW extract used in the present investigation contained 26.7% (wt/wt) phenolic compounds, of which 31% (as evaluated by comparison with an authentic standard) was hydroxytyrosol. The individual components were separated and collected, and their antioxidant capacity was evaluated in a model of copper sulfateoxidized LDL.10 The results demonstrated that only hydroxytyrosol was able to inhibit LDL oxidation (not shown).
The extract was dissolved in ethanol and was administered to the rats by gavage between 9:00 and 9:30 AM (5% ethanol, ie, 50 µL/rat). Control groups were given 5% ethanol in water.
Experimental Protocols
Animals were randomly assigned to 2 experimental groups. The
first group (n=6) was given the OMWW extract (5 mg/kg, once a day, ie,
414 µg ·
kg-1 ·
d-1 of hydroxytyrosol),
and the second (n=6) the vehicle alone. Rats received the treatments
for 2 days, after which they were exposed daily for 4 days to
sidestream smoke as described below, 15 minutes after receiving the
compounds under investigation. Every other day (days 0, 2, and 4 after
beginning of smoking), rats were placed in metabolic cages,
with free access to food and tap water, for the collection of urines.
Twenty-four-hour urines were collected in the morning and stored at
-80°C.
Exposure of Rats to Passive Smoke
Rats were placed in a sealed Plexiglas box that was filled with
smoke from 1 cigarette (nicotine 1.2 mg, tar 12 mg); the animals were
kept in the smoke-filled chamber for 1 exposure of 20 minutes
duration. The average CO volume in the box during the smoke exposure
was 0.26±0.05%, as measured by a CO detector tube (Auergesellschaft
GmbH).11
At the end of the treatment, the rats were returned either to their cage or to a metabolic cage for the collection of 24-hour urine.
Evaluation of 8-iso-PGF2
Urinary Excretion
Urinary 8-iso-PGF2
was purified by a
double-extraction method according to Wang et al,12 with
modifications,13 followed by quantification by an enzyme
immunoassay. Acetylcholine esterase tracer was obtained from Cayman
Chemical, and the specific antibody was kindly provided by the late Dr
J. Maclouf (Hopital Lariboisiere, Paris). Urinary
creatinine concentrations were measured with a commercial
kit (Sigma Chemical Co). Results were corrected for the recovery of
radiolabeled tracer and expressed as pg/mg creatinine.
Unless stated otherwise, data were expressed as mean±SEM of 6
observations, and comparisons were performed by use of the
Wilcoxon rank sum test.
| Results |
|---|
|
|
|---|
under
basal conditions averaged 264±82 pg/mg creatinine
(mean±SD, n=12) and was not significantly different between controls
and OMWW-treated rats. Levels of 8-iso-PGF2
in
urines of nontreated rats after 2 exposures to sidestream smoke rose
from 237±34 to 319±35 pg/mg creatinine (n=6), ie, an
increase of 82±46 pg/mg creatinine (Figure 1A
was 375±58
pg/mg creatinine, ie, an increase of 145±33 pg/mg
creatinine (Figure 1A
excretion in
this group of 375±51 pg/mg creatinine (n=6).
|
| Discussion |
|---|
|
|
|---|
Passive smoking is known to induce several effects normally associated
with active smoking. For example, we have previously observed an
increase in bronchial reactivity in animals exposed to passive
smoking,11 and we are now reporting that repeated exposure
of rats to sidestream smoke results in a significant elevation of
urinary excretion of 8-iso-PGF2
(iPF2
-III), a reliable marker of oxidative
stress in vivo.3 Furthermore, enhanced urinary excretion
of 8-iso-PGF2
has been reported in smokers as
well as in different pathologies associated with increased levels of
oxidative stress.7 14 In particular, an increase in
8-iso-PGF2
urinary excretion has been reported
in patients suffering from chronic obstructive pulmonary
disease, in whom a significant correlation with inflammation and
respiratory functions was also observed.15 The increase in
the urinary excretion of 8-iso-PGF2
, evaluated
semiquantitatively by immunoassay, after 2 and 4 days of passive
smoking in rats reported here suggests that enhanced oxidative stress
represents an immediate-early feature of the inflammatory
response associated with lung exposure to smoke components, although we
cannot rule out the possibility that other,
cyclooxygenase-derived, compounds might be detected
by this assay and contribute to the high interindividual variability
observed.
It is noteworthy that the OMWW extract used in this study contained
8.3% hydroxytyrosol as the active antioxidant compound and therefore,
the actual dose of hydroxytyrosol administered to the laboratory
animals was only 414 µg ·
kg-1 ·
d-1. In a recent study
using apoE-deficient mice, vitamin E decreased isoprostane, ie,
iPF2
-VI, levels at an estimated dose of
270
mg · kg-1 ·
d-116 ; although
experimental conditions were different in the 2 studies, our results
suggest that the hydroxytyrosol present in OMWW extracts is very
effective in decreasing the oxidative stress associated with passive
cigarette smoke. The amphiphilic nature of this compound, as opposed to
the lipophilic characteristics of vitamin E, might provide an
additional protection against oxidative processes that take place in
biological systems at the water-lipid interface.
Evidence of a dose-dependent absorption of hydroxytyrosol in humans was recently obtained in our laboratory17 ; the present investigation indicates that hydroxytyrosol retains its antioxidant activity in vivo, and additional work is needed to evaluate its potential activity in humans.
| Acknowledgments |
|---|
Received August 17, 2000; revision received August 31, 2000; accepted August 31, 2000.
| References |
|---|
|
|
|---|
2. Hertog MGL, Feskens EJM, Hollman PCH, et al. Dietary antioxidant flavonoids and risk of coronary heart disease. The Zutphen elderly study. Lancet. 1993;342:10071011.[Medline] [Order article via Infotrieve]
3.
Patrono C, FitzGerald GA. Isoprostanes: potential
markers of oxidation stress in atherothrombotic disease.
Arterioscler Thromb Vasc Biol. 1997;17:23092315.
4. Keys A. Mediterranean diet and public health: personal reflections. Am J Clin Nutr. 1995;61:1321S1323S.[Abstract]
5. Visioli F, Galli C. The effect of minor constituents of olive oil on cardiovascular disease: new findings. Nutr Rev. 1998;56:142147.[Medline] [Order article via Infotrieve]
6. Visioli F, Romani A, Mulinacci N, et al. Antioxidant and other biological activities of olive mill waste waters. J Agric Food Chem. 1999;47:33973401.[Medline] [Order article via Infotrieve]
7.
Morrow J, Frei B, Longmire AW, et al. Increase in
circulating products of lipid peroxidation
(F2-isoprostanes) in smokers. N Engl
J Med. 1995;332:11981203.
8.
Celermajer DS, Adams MR, Clarkson P, et al. Passive
smoking and impaired endothelium-dependent
arterial dilatation in healthy young adults. N
Engl J Med. 1996;334:150155.
9. Zhu B-Q, Sun Y-P, Sievers RE, et al. Passive smoking increases experimental atherosclerosis in cholesterol-fed rabbits. J Am Coll Cardiol. 1993;21:225232.[Abstract]
10. Visioli F, Bellomo G, Montedoro G, et al. Low density lipoprotein oxidation is inhibited in vitro by olive oil constituents. Atherosclerosis. 1995;117:2532.[Medline] [Order article via Infotrieve]
11. Omini C, Hernandez A, Zuccari G, et al. Passive cigarette smoke exposure induces airway hyperreactivity to histamine but not to acetylcholine in guinea-pigs. Pulm Pharmacol. 1990;3:145150.[Medline] [Order article via Infotrieve]
12.
Wang Z, Ciabattoni G, Creminon C, et al. Immunological
characterization of urinary 8-epi-prostaglandin
F2
excretion in man. J Pharmacol
Exp Ther. 1995;275:94100.
13.
Sautebin L, Ianaro A, Rombolà L, et al.
Cyclooxygenase-2-dependent generation of
8-epi-prostaglandin F2
by
lipopolysaccharide-activated J774 macrophages.
Inflamm Res. 1999;48:503508.[Medline]
[Order article via Infotrieve]
14.
Davi G, Alessandrini P, Mezzetti A, et al. In vivo
formation of
8-epi-prostaglandin-F2
is
increased in hypercholesterolemia.
Arterioscler Thromb Vasc Biol. 1997;17:32303235.
15.
Praticó D, Basili S, Vieri M, et al.
Chronic obstructive pulmonary disease is associated with an
increase in urinary levels of isoprostane F2alpha-III, an index of
oxidant stress. Am J Respir Crit Care Med. 1998;158:17091714.
16. Praticó D, Tangirala RK, Rader DJ, et al. Vitamin E suppresses isoprostane generation in vivo and reduces atherosclerosis in apoE-deficient mice. Nat Med. 1998;4:11891192.[Medline] [Order article via Infotrieve]
17. Visioli F, Galli C, Bornet F, et al. Olive oil phenolics are dose-dependently absorbed in humans. FEBS Lett. 2000;468:159160.[Medline] [Order article via Infotrieve]
This article has been cited by other articles:
![]() |
H. Schroder, R. de la Torre, R. Estruch, D. Corella, M. A. Martinez-Gonzalez, J. Salas-Salvado, E. Ros, F. Aros, G. Flores, E. Civit, et al. Alcohol consumption is associated with high concentrations of urinary hydroxytyrosol Am. J. Clinical Nutrition, November 1, 2009; 90(5): 1329 - 1335. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. A. Carluccio, M. A. Ancora, M. Massaro, M. Carluccio, E. Scoditti, A. Distante, C. Storelli, and R. De Caterina Homocysteine induces VCAM-1 gene expression through NF-{kappa}B and NAD(P)H oxidase activation: protective role of Mediterranean diet polyphenolic antioxidants Am J Physiol Heart Circ Physiol, October 1, 2007; 293(4): H2344 - H2354. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Basyigit, M. Tugay, M.O. Dilioglugil, F. Yildiz, H. Maral, and S. Sozubir Protective effects of N-acetylcysteine on peroxidative changes of the fetal rat lungs whose mothers were exposed to cigarette smoke Human and Experimental Toxicology, February 1, 2007; 26(2): 99 - 103. [Abstract] [PDF] |
||||
![]() |
M.-I. Covas, K. Nyyssonen, H. E. Poulsen, J. Kaikkonen, H.-J. F. Zunft, H. Kiesewetter, A. Gaddi, R. de la Torre, J. Mursu, H. Baumler, et al. The effect of polyphenols in olive oil on heart disease risk factors: a randomized trial. Ann Intern Med, September 5, 2006; 145(5): 333 - 341. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Acin, M. A. Navarro, J. M. Arbones-Mainar, N. Guillen, A. J. Sarria, R. Carnicer, J. C. Surra, I. Orman, J. C. Segovia, R. d. l. Torre, et al. Hydroxytyrosol Administration Enhances Atherosclerotic Lesion Development in Apo E Deficient Mice J. Biochem., September 1, 2006; 140(3): 383 - 391. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Raupach, K. Schafer, S. Konstantinides, and S. Andreas Secondhand smoke as an acute threat for the cardiovascular system: a change in paradigm Eur. Heart J., February 2, 2006; 27(4): 386 - 392. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. M. Bitler, T. M. Viale, B. Damaj, and R. Crea Hydrolyzed Olive Vegetation Water in Mice Has Anti-Inflammatory Activity J. Nutr., June 1, 2005; 135(6): 1475 - 1479. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Barnoya and S. A. Glantz Cardiovascular Effects of Secondhand Smoke: Nearly as Large as Smoking Circulation, May 24, 2005; 111(20): 2684 - 2698. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Santus, A. Sola, P. Carlucci, F. Fumagalli, A. Di Gennaro, M. Mondoni, C. Carnini, S. Centanni, and A. Sala Lipid Peroxidation and 5-Lipoxygenase Activity in Chronic Obstructive Pulmonary Disease Am. J. Respir. Crit. Care Med., April 15, 2005; 171(8): 838 - 843. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Weinbrenner, M. Fito, R. d. l. Torre, G. T. Saez, P. Rijken, C. Tormos, S. Coolen, M. F. Albaladejo, S. Abanades, H. Schroder, et al. Olive Oils High in Phenolic Compounds Modulate Oxidative/Antioxidative Status in Men J. Nutr., September 1, 2004; 134(9): 2314 - 2321. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Visioli, C. Galli, S. Grande, K. Colonnelli, C. Patelli, G. Galli, and D. Caruso Hydroxytyrosol Excretion Differs between Rats and Humans and Depends on the Vehicle of Administration J. Nutr., August 1, 2003; 133(8): 2612 - 2615. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Miro-Casas, M.-I. Covas, M. Farre, M. Fito, J. Ortuno, T. Weinbrenner, P. Roset, and R. de la Torre Hydroxytyrosol Disposition in Humans Clin. Chem., June 1, 2003; 49(6): 945 - 952. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. A. Carluccio, L. Siculella, M. A. Ancora, M. Massaro, E. Scoditti, C. Storelli, F. Visioli, A. Distante, and R. De Caterina Olive Oil and Red Wine Antioxidant Polyphenols Inhibit Endothelial Activation: Antiatherogenic Properties of Mediterranean Diet Phytochemicals Arterioscler Thromb Vasc Biol, April 1, 2003; 23(4): 622 - 629. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. L. Tuck, M. P. Freeman, P. J. Hayball, G. L. Stretch, and I. Stupans The In Vivo Fate of Hydroxytyrosol and Tyrosol, Antioxidant Phenolic Constituents of Olive Oil, after Intravenous and Oral Dosing of Labeled Compounds to Rats J. Nutr., July 1, 2001; 131(7): 1993 - 1996. [Abstract] [Full Text] [PDF] |
||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Circulation Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2000 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |