Metal-chelating properties, electrochemical behavior, scavenging and cytoprotective activities of six natural phenolics

Abstract

Chelation, electrochemical, antioxidant and cytoprotective properties of six phenolics - cynarin and caffeic, chlorogenic, ferulic, protocatechuic and rosmarinic acids were studied on the following models: (i) chelation of transition metals, (ii) quenching of the diphenylpicrylhydrazyl radical (DPPH), (iii) determination of half-wave potential, (iv) erythrocytes or mitochondrial membranes damaged by tert-butyl hydroperoxide (tBH) and (v) a primary culture of rat hepatocytes intoxicated by Cu(II) and Fe(III) or tBH. All phenolics suppressed cell membrane damage induced by transition metals or tBH. The protectivity correlated with their capacity to bind transition metals, to scavenge DPPH radical and with the value of half-wave potentials. In in vitro assays, the most promising was rosmarinic acid.

Ameliorative Effects of Caffeic Acid on Lead Accumulation and Oxidative Stress in Lead-Exposed Mice

“…Despite known property of CA as an antioxidant [7,8], its administration in the present work had no significant effect on increased values of MDA in erythrocyte haemolysate of mice in group 3 as compared to lead-exposed animals in group 2. Despite the present findings, Psotova et al [32] reported that CA was able to decrease the augmented levels of lipid peroxidation and to eliminate intracellular GSH decline of hepatocytes intoxicated by Fe (III), Cu (II) and tertbutyl hydroperoxide. In addition, CA significantly reduced lipid peroxidation and restored the levels of antioxidant defense in the liver of rats intoxicated with nickel [8].…”

“…The results of an in vitro study showed that some natural phenolics including caffeic, chlorogenic, ferulic, protocatechuic and rosmarinic acids behaved as antioxidants with chemoprotective effects in some low concentration ranges [32]. On the other hand, protocatechuic acid at concentrations above 2.5 mM showed in vitro pro-oxidation activity linked to the decrease in reduced glutathione and increase in cellular TBARS [33].…”

Caffeic acid protects rat heart mitochondria against isoproterenol-induced oxidative damage

“…The intake of CA from foods mainly from tomatoes and potatoes was estimated to be about 0.2 mg/kg body weight per day (National Research Council 1996). Furthermore, CA exhibits multipharmacological effects such as antioxidant (Kono et al 1997), free radical scavenging (Gulcin 2006), and chelator of metal ions (Psotova et al 2003). A previous scientific report has revealed that CA inhibits oxidation of lowdensity lipoprotein in vitro and might therefore protect against CVD (Nardini et al 1995).…”

Antioxidant Activity of Caffeic Acid and Its Derivatives

“…W badaniach in vitro wykazano, że chelatowanie jonów metali przez fenolokwasy chroni błonę komórkową przed uszkodzeniami indukowanymi przez jony metali przejściowych. Kwas kawowy może tworzyć kompleksy z jonami Cu 2+ , Fe 2+ oraz Fe 3+ [28]. Wiązanie jonów żelaza in vitro przez kwas kawowy badano, m.in.…”