Seven men and seven women participated in a randomized crossover trial to study the effect of intake of parsley (Petroselinum crispum), containing high levels of the flavone apigenin, on the urinary excretion of flavones and on biomarkers for oxidative stress. The subjects received a strictly controlled diet low in flavones and other naturally occurring antioxidants during the 2 weeks of intervention. This basic diet was supplemented with parsley providing 3⋅73-4⋅49 mg apigenin/MJ in one of the intervention weeks. Urinary excretion of apigenin was 1⋅59-409⋅09 g/MJ per 24 h during intervention with parsley and 0-112⋅27 g/MJ per 24 h on the basic diet (P Ͻ 0⋅05). The fraction of apigenin intake excreted in the urine was 0⋅58 (SE 0⋅16) % during parsley intervention. Erythrocyte glutathione reductase (EC 1.6.4.1; GR) and superoxide dismutase (EC 1.15.1.1; SOD) activities increased during intervention with parsley (P Ͻ 0⋅005) as compared with the levels on the basic diet, whereas erythrocyte catalase (EC 1.11.1.6) and glutathione peroxidase (EC 1.11.1.9) activities did not change. No significant changes were observed in plasma protein 2-adipic semialdehyde residues, a biomarker of plasma protein oxidation. In this short-term investigation, an overall decreasing trend in the activity of antioxidant enzymes was observed during the 2-week study. The decreased activity of SOD was strongly correlated at the individual level with an increased oxidative damage to plasma proteins. However, the intervention with parsley seemed, partly, to overcome this decrease and resulted in increased levels of GR and SOD. Apigenin: Antioxidant status: Urinary excretionApigenin is a flavone found in vegetables, seasonings (Kühnau, 1976) and oranges (Fernandez de Simon et al. 1992), and it possesses antioxidant activity in vitro (Fraga et al. 1987;van Acker et al. 1996). Potent biological effects of this flavonoid have been described in vitro and in vivo. Apigenin has been ascribed anticarcinogenic (Wei et al. 1989;Birt et al. 1997), anti-inflammatory (Lee et al. 1993 and antimutagenic (Kuo et al. 1992) properties. Thus, development of a biomarker for intake of apigenin is important in order to evaluate the potential health effects of this particular dietary component. There has only been one previously published attempt to determine the urinary excretion of apigenin in human subjects after ingestion of an apigenin-containing camomile (Matricaria recutita) extract (Tschiersch & Hölzl, 1993). However, due to lack of specificity and sensitivity the method failed to detect any apigenin in the urine.Parsley (Petroselinum crispum) contains large amounts of the flavone apigenin (Justesen et al. 1998), and the low concentration of other flavonoids in this plant makes it suitable for an intervention study with a natural source of apigenin.In the present study we report on the relationship between daily intake of parsley and urinary excretion of apigenin. The antioxidative effect of the parsley intervention was investigated by measuring the activity ...

Ambient particulate air pollution assessed as outdoor concentrations of particulate matter less than or equal to 2.5 micro m in diameter (PM(2.5)) in urban background has been associated with cardiovascular diseases at the population level. However, the significance of individual exposure and the involved mechanisms remain uncertain. We measured personal PM(2.5) and carbon black exposure in 50 students four times in 1 year and analyzed blood samples for markers of protein and lipid oxidation, for red blood cell (RBC) and platelet counts, and for concentrations of hemoglobin and fibrinogen. We analyzed protein oxidation in terms of gamma-glutamyl semialdehyde in hemoglobin (HBGGS) and 2-aminoadipic semialdehyde in hemoglobin (HBAAS) and plasma proteins (PLAAS), and lipid peroxidation was measured as malondialdehyde (MDA) in plasma. Median exposures were 16.1 micro g/m(3) for personal PM(2.5) exposure, 9.2 micro g/m(3) for background PM(2.5) concentration, and 8.1 X 10(-6)/m for personal carbon black exposure. Personal carbon black exposure and PLAAS concentration were positively associated (p < 0.01), whereas an association between personal PM(2.5) exposure and PLAAS was only of borderline significance (p = 0.061). A 3.7% increase in MDA concentrations per 10 micro g/m(3) increase in personal PM(2.5) exposure was found for women (p < 0.05), whereas there was no significant relationship for the men. Similarly, positive associations between personal PM(2.5)exposure and both RBC and hemoglobin concentrations were found only in women (p < 0.01). There were no significant relationships between background PM(2.5) concentration and any of the biomarkers. This suggests that exposure to particles in moderate concentrations can induce oxidative stress and increase RBCs in peripheral blood. Personal exposure appears more closely related to these biomarkers potentially related to cardiovascular disease than is ambient PM(2.5) background concentrations.

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Background: Epidemiologic studies suggest that foods rich in flavonoids might reduce the risk of cardiovascular disease. Objective: Our objective was to investigate the effect of intake of flavonoid-containing black currant and apple juice on urinary excretion of quercetin and on markers of oxidative status. Design: This was a crossover study with 3 doses of juice (750, 1000, and 1500 mL) consumed for 1 wk by 4 women and 1 man corresponding to an intake of 4.8, 6.4, and 9.6 mg quercetin/d. Results: Urinary excretion of quercetin increased significantly with dose and with time. The fraction excreted in urine was 0.29-0.47%. Plasma quercetin did not change with juice intervention. Plasma ascorbate increased during intervention because of the ascorbate in the juice. Total plasma malondialdehyde decreased with time during the 1500-mL juice intervention, indicating reduced lipid oxidation in plasma. Plasma 2-amino-adipic semialdehyde residues increased with time and dose, indicating a prooxidant effect of the juice, whereas erythrocyte 2-aminoadipic semialdehyde and ␥-glutamyl semialdehyde concentrations, Trolox-equivalent antioxidant capacity, and ferric reducing ability of plasma did not change. Glutathione peroxidase activity increased significantly with juice dose. Conclusions: Urinary excretion of quercetin seemed to be a small but constant function of quercetin intake. Short-term, high intake of black currant and apple juices had a prooxidant effect on plasma proteins and increased glutathione peroxidase activity, whereas lipid oxidation in plasma seemed to decrease. These effects might be related to several components of the juice and cannot be attributed solely to its quercetin content.Am J Clin Nutr 1999;69:87-94. KEY WORDSQuercetin, urinary excretion, biomarker, human intervention, antioxidative status, malondialdehyde, protein oxidation, apple juice, black currant juice, glutathione peroxidase, flavonoids INTRODUCTIONResults from some epidemiologic studies suggest that a high intake of foods rich in flavonols and flavones might reduce the risk of cardiovascular disease (1-3). The potential beneficial mechanism could be the antioxidative properties of these compounds. Of the dietary plant flavonoids, quercetin and other flavonols are quantitatively important. The mean intake of quercetin has been estimated at 12 mg/d in Denmark (4) and 16 mg/d in Netherlands (5).For flavonoids to exert a protective effect on cardiovascular disease it is reasonable to assume that they have to be absorbed. In foods, most flavonoids are present as glycosides, ie, bound to a sugar moiety. Few data are available on absorption of quercetin or quercetin glycosides in humans. The results of a single-dose study by Hollman et al (6), carried out in 9 ileostomy patients, suggested that the absorption of quercetin conjugates from foods may be more efficient than that of the pure aglycone. They observed 52% disappearance in the small intestine after ingestion of 89 mg conjugated quercetin from onions, and a disappearance of only...

Artichoke (Cynara scolymus L.), an edible vegetable from the Mediterranean area, is a good source of natural antioxidants such as vitamin C, hydroxycinnamic acids, and flavones. The antioxidant activity of aqueous−organic extracts of artichoke were determined using three methods:  (a) free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH•) scavenging, (b) ferric-reducing antioxidant power (FRAP), and (c) inhibition of copper(II)-catalyzed in vitro human low-density lipoprotein (LDL) oxidation. In addition, the present study was performed to investigate the ability of the edible portion of artichoke to alter in vivo antioxidative defense in male rats using selected biomarkers of antioxidant status. One gram (dry matter) had a DPPH• activity and a FRAP value in vitro equivalent to those of 29.2 and 62.6 mg of vitamin C and to those of 77.9 and 159 mg of vitamin E, respectively. Artichoke extracts showed good efficiency in the inhibition in vitro of LDL oxidation. Neither ferric-reducing ability nor 2,2‘-azinobis(3-ethylbenzothiazolin-6-sulfonate) radical scavenging activity was modified in the plasma of the artichoke group with respect to the control group. Among different antioxidant enzymes measured (superoxide dismutase, gluthatione peroxidase, gluthatione reductase, and catalase) in erythrocytes, only gluthatione peroxidase activity was elevated in the artichoke group compared to the control group. 2-Aminoadipic semialdehyde, a protein oxidation biomarker, was decreased in plasma proteins and hemoglobin in the artichoke-fed group versus the control group. In conclusion, the in vitro protective activity of artichoke was confirmed in a rat model. Keywords: Artichoke; polyphenols; antioxidant activity; radical scavenging; redox potential; low-density lipoprotein oxidation; biomarkers; protein oxidation; rats