The influence of triphenylantimony(V) catecholate and its spiroendoperoxide on lipid peroxidation

The effects of triphenylantimony(V) catecholate Ph3Sb(Cat) (1) and its spiroendoperoxide Ph3Sb(L-O2) (2) (Cat = 3,6-di-tert-butyl-4,5-dimethoxycatecholate) on lipid peroxidation (LP) in vitro and in vivo were examined in BALB/c line mice. A comparative study of the impact of compounds 1 and 2 on LP under similar conditions was made by measuring the formation of thiobarbituric acid reactive substances (TBARS). The anti- or pro-oxidant action of complexes 1 and 2 may be caused by the different redox level of the ligand acting as radical scavenger and/or by the bound molecular oxygen promoting the oxidation process. Biological experiments (in vitro and in vivo) were performed using mouse tissue homogenates. Decreasing TBARS concentration was observed in all examined tissues and blood serum (in vitro as well as in vivo) for catecholate 1. These results indicate inhibition of LP in the presence of complex 1. In contrast to 1, spiroendoperoxide 2 increases the level of TBARS in tissue homogenates. Minor fluctuations of TBARS concentration in erythrocytes and in blood serum indicate the absence of an obvious anti/pro-oxidant influence of 2 on the LP process in vivo. The role of catecholate fragment was found to be essential in explaining antioxidant properties. Copyright © 2014 John Wiley & Sons, Ltd.