The effect of high dose antioxidant treatments on redox homeostasis in rats

Diet related antioxidant bioactive compounds and metal elements could modulate the signal transduction routes in vitro, although their modes of actions in vivo are not yet known in detail. Antioxidant overflow could mean serious problems in several signal transduction pathways, therefore the multifactorial actions of natural products must be analyzed in vivo studies on redox homeostasis. Our aim was to present the effect of „Fruit and vegetable color concentration“ (FVCC) in short term studies on normo- and hyperlipidemic rats, treated with FVCC (1g/bwkg/day for 10 days). Plasma, erythrocyte and liver homogenate were examined. The redox balance did not change significantly, when the healthy animals were treated with the FVCC neither in the plasma nor in the erythrocyte opposite to the liver homogenate, where the parameters became worse. In hyperlipidemy, the treatment caused a significant elevation in H-donating ability, reducing power, free SH-group concentration and decrease in free radical level of plasma. In the liver all measured parameters (H-donating ability, reducing power, free SH-groups, diene conjugates, and free radical level) changed unfavorably. The data of routine laboratory parameters (GLUC, CREA, ALP, TG) were pathological in sick animals after treatment, opposite to healthy animals. We concluded from these results that bioactive compounds of FVCC take part in redox homeostasis in healthy and hyperlipidemic animals differently. Antioxidants as well as metal elements influence the signal transduction pathways, can help to restore normal functions of organism, but a high dose consumption of bioactive agents is contraindicated. The changes in hyperlipidemy were more considerable, than in normolipidemy

Support: 1B/047 Széchenyi and ETT 002/2003 Projects.