<I>In Vitro</I> Effects of Quercetin on Oxidative Stress Mediated in Human Erythrocytes by Benzoic Acid and Citric Acid

Abstract

Benzoic acid (BA) and citric acid (CA) are food additives commonly used in many food products. Food additives play an important role in food supply but they can cause various harmful effects. The in vitro adverse effects of BA and CA and the protective effect of quercetin on human erythrocytes were investigated by measuring malondialdehyde (MDA) levels and superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) activities. Erythrocytes were incubated with BA and CA, at three doses of 50, 100 and 200 microg/ml, and quercetin, at a concentration of 10 microM. After BA and CA application, a dose-dependent increase in MDA level and decreases in SOD, CAT, GST and GPx activities were found in erythrocytes. Among the two food additives, BA exerted a more harmful influence on human erythrocytes than CA. The protective effects of quercetin against oxidative stress--induction in the human erythrocytes by CA and BA, were found when these two food additives were applied at each of three doses of 50, 100 and 200 microg/ml. However, complete protection of quercetin against CA toxicity was only observed when this agent was applied at a lower dose of 50 microg/ml. Quercetin did not completely protect erythrocytes even at the lowest concentration of BA.

Nephrotoxic effects of lead nitrate exposure in diabetic and nondiabetic rats: Involvement of oxidative stress and the protective role of sodium selenite

“…Antioxidant enzymes are important cell protectors against oxidative stress induced injuries. The principal endogenous antioxidants that show effects on ROS are SOD, GPx, GST, and CAT (Baş et al, ). The activities of these enzymes have been used to evaluate oxidative stress in cells.…”

“…The GPx protects cell membranes from oxidative damage via catalyses H 2 O 2 conversion to H 2 O. SOD and CAT catalyze the dismutation of superoxide anions to the oxygen and H 2 O 2 , H 2 O 2 conversion to the water like as GPx respectively (Messarah et al, ). GST catalyzes the conjugation of several electrophilic substrates to the thiol group of GSH so it produces less toxic forms (Baş et al, ). Heavy metals have adverse effects on antioxidant enzymes.…”

“…Previous studies have reported also that Pb increased the LPO level (Dewanjee et al, ). Malondialdehyde (MDA) is main product of LPO so enhanced MDA level is a principal determinant of LPO (Demir et al, ; Baş et al, ). Pb induces increasing production of MDA (Lakshmi et al, ).…”

Antioxidant Status, Lipid Peroxidation and Testis-histoarchitecture Induced by Lead Nitrate and Mercury Chloride in Male Rats

“…SOD catalyzes the dismutation of superoxide radicals to hydrogen peroxide and molecular oxygen [ 10 ].CAT catalyzes the reduction of H 2 O 2 to water and oxygen and protects the cell against H 2 O 2 induced oxidative damage [ 11 ]. The GPx and GST catalyse the reduction of H 2 O 2 to H 2 O and the conjugation of electrophilic substrates to the thiol group of GSH so it produces less toxic forms, respectively [ 12,13 ]. Male germ cells are more susceptible to oxidative stress than other cells, because they have higher polyunsaturated fatty acids in their membranes than somatic cells.…”

Excess of dietary benzoic acid supplementation leads to growth retardation, hematological abnormality and organ injury of piglets

“…GSH-Px is a peroxide decomposition enzyme, using glutathione (GSH) as a substrate to transformH et al, 2013). GST is provided with antioxidation and detoxification, transforming toxic materials into less toxic forms(Mansour and Mossa.2010) Baş et al (2014). have reported that 50, 100 and 200 μg/mL benzoic acid may induce oxidative stress in the human erythrocytes.…”