The effect of quercetin on plasma oxidative status, C-reactive protein and blood pressure in women with rheumatoid arthritis.
BACKGROUND
Considering the increased production of free radicals and inflammatory factors in rheumatoid arthritis (RA) and the effects of bioflavonoid quercetin on reducing oxidative stress, inflammation and blood pressure, the present study examined the effects of bioflavonoid quercetin on total antioxidant capacity (TAC) of plasma, lipid peroxidation and blood pressure in women with RA.


METHODS
The current study was a randomized double-blind clinical trial in which 51 women with RA aged 19-70 years, were participated. Patients were assigned into quercetin (500 mg/day) or placebo groups for 8 weeks. Dietary intake was recorded using 24-h dietary recall questionnaire and the physical activity was assessed through an international short questionnaire of physical activity at the beginning and end of the study. Plasma TAC and malondialdehyde (MDA) using colorimetric method, oxidized low density lipoprotein (ox-LDL) and high sensitivity C-reactive protein (hs-CRP) using enzyme-linked immunosorbent assay method and also blood pressure were measured at the beginning and end of intervention.


RESULTS
After 8 weeks there were no significant differences in TAC of plasma, ox-LDL, MDA, hs-CRP, systolic and diastolic blood pressure between quercetin and placebo groups and in each group comparing before and after.


CONCLUSIONS
In this study, quercetin had no effect on oxidative and inflammatory status of plasma and blood pressure in patients with RA. Further studies are needed to ensure the effect of quercetin on oxidative stress and inflammation in human.
Department of Nutrition and Biochemistry, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
Fatemeh
F
Javadi
Department of Nutrition and Biochemistry, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran ; Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Iran.
Shahryar
S
Eghtesadi
Department of Rheumatology, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Arman
A
Ahmadzadeh
Department of Nutrition and Biochemistry, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran ; Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Iran.
Naheed
N
Aryaeian
Department of Rheumatology, Firouzgar Hospital, Tehran University of Medical Sciences, Tehran, Iran.
Mozhdeh
M
Zabihiyeganeh
Department of Epidemiology and Bio statistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
Abbas Rahimi
AR
Foroushani
Department of Nutrition and Biochemistry, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran ; Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Iran.
Shima
S
Jazayeri
Blood pressure; lipid peroxidation; quercetin; rheumatoid arthritis; total antioxidant capacity