Lidocaine: An inhibitor in the free‐radical‐induced hemolysis of erythrocytes

Abstract

Lidocaine was reported to protect erythrocytes from hemolysis induced by 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH). Since AAPH-induced hemolysis was a convenient in vitro experimental system to mimic erythrocytes undergoing peroxyl radicals attack, the aim of this work was to investigate the antioxidant effect of lidocaine on AAPH-induced hemolysis by chemical kinetics. As a result, one molecule of lidocaine can only trap 0.37 radical, much lower than melatonin. Meanwhile, lidocaine cannot protect erythrocytes from hemolysis induced by hemin, which the mechanism of hemolysis was due to the erythrocyte membrane destroyed by hemin. Accordingly, lidocaine protected erythrocytes by scavenging radicals preferentially rather than by stabilizing membrane. Moreover, the interactions of lidocaine with two radical species, including 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) radical cation (ABTS(+*)) and 2,2'-diphenyl-1-picrylhydrazyl (DPPH), indicated that lidocaine can reduce ABTS(+*) with 260 microM as the 50% inhibition concentration (IC(50)) and cannot react with DPPH. Thus, lidocaine served as a reductant rather than a hydrogen donor to interact with radicals. Finally, the quantum calculation proved that, compared with the melatonin radical, the stabilization of N-centered radical of lidocaine was higher than the amide-type N-centered radical but lower than the indole-type N-centered radical in melatonin. These results provided basic information for lidocaine to be an antiradical drug.

Comparison of antioxidant effectiveness of lipoic acid and dihydrolipoic acid

“…AAPH-induced hemolysis of erythrocytes was carried out following the description in the literature [19]. Erythrocytes were washed by phosphate-buffered saline (PBS4: 150 mM NaCl, 8.1 mM Na 2 HPO 4 , 1.9 mM NaH 2 PO 4 , 10 μM EDTA) to remove residue plasma.…”

Topical Application of Lidocaine and Bupivacaine to Disbudding Wounds in Dairy Calves: Safety, Toxicology and Wound Healing

“…Typically, however, this is only in the setting of acute toxicity with other factors predisposing to oxidative stress and methaemoglobinaemia [52]. On the other hand, other reports have documented that lidocaine provides a protective effect against intravascular haemolysis [53]. There was a low grade but statistically significant reduction in red blood cells and haemoglobin in blood in animals in the 5× dose group (Group 4) compared to the placebo (Group 1) group; however, haemoglobin and red blood cell values in both groups remained well within the normal range for calves, and mean corpuscular volume and haemoglobin concentration were also not significantly different between groups.…”