In the present study, the biochemical effects of vitamin C, and aqueous extract of
green tea (GTE) on rheumatoid arthritis (RA) of rats were investigated. The
oxidative stress indices and the antioxidant levels were evaluated. Forty albino male
rats were divided into four groups (10 rats each): control group, collagen II -induced
RA group (C II group), CII group treated with vitamin C (C II + Vit. C), and CII
group treated with green tea extract (GTE) (C II + GTE). After 6 weeks of
antioxidants treatment, the plasma levels of lipid peroxides (LPO), nitric oxide (NO),
ceruloplasmin (PC), and glutathione (GSH) were detected using colorimetric
methods. The plasma levels ofcopper (Cu) and zinc (Zn)were determined using
atomic absorption/flame emission spectrometer. In C II treated group, the levels of
LPO, NO, CP and Cu were significantly higher but the levels of; GSH and Zn were
significantly lower than controls. The levels of GSH and Zn were significantly
increased but the levels of NO, Cu and CPwere significantly decreased in the
vitamins C treated groups in comparison with C II –treated group. In the C II + GTE
group, the levels of LPO, NO, CP and Cu were significantly decreased but the levels
of GSH, and Zn were significantly increased in comparison with C II –treated group.
The present study suggests that proper antioxidants intake may reduce free radical
generation and improve antioxidant status in RA. GTE and vitamin C may effectively
normalize in different degrees the impaired oxidant/ antioxidant system and may be
useful in delaying the complication of RA.