Dietary phenolic acids act as effective antioxidants in membrane models and in cultured cells, exhibiting proapoptotic effects in leukaemia cells.
Caffeic, syringic, and protocatechuic acids are phenolic acids derived directly from food intake or come from the gut metabolism of polyphenols. In this study, the antioxidant activity of these compounds was at first evaluated in membrane models, where caffeic acid behaved as a very effective chain-breaking antioxidant, whereas syringic and protocatechuic acids were only retardants of lipid peroxidation. However, all three compounds acted as good scavengers of reactive species in cultured cells subjected to exogenous oxidative stress produced by low level of H(2)O(2). Many tumour cells are characterised by increased ROS levels compared with their noncancerous counterparts. Therefore, we investigated whether phenolic acids, at low concentrations, comparable to those present in human plasma, were able to decrease basal reactive species. Results show that phenolic acids reduced ROS in a leukaemia cell line (HEL), whereas no effect was observed in normal cells, such as HUVEC. The compounds exhibited no toxicity to normal cells while they decreased proliferation in leukaemia cells, inducing apoptosis. In the debate on optimal ROS-manipulating strategies in cancer therapy, our work in leukaemia cells supports the antioxidant ROS-depleting approach.
Department of Biochemistry G. Moruzzi, Alma Mater Studiorum, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy. laura.zambonin@unibo.it
Laura
L
Zambonin
Cristiana
C
Caliceti
Francesco
F
Vieceli Dalla Sega
Diana
D
Fiorentini
Silvana
S
Hrelia
Laura
L
Landi
Cecilia
C
Prata
D000578:Amidines / Q000378:metabolism; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004032:Diet; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D006801:Humans; D062385:Hydroxybenzoates / Q000737:chemistry / Q000494:pharmacology*; D007938:Leukemia / Q000201:enzymology / Q000473:pathology*; D015227:Lipid Peroxidation / Q000187:drug effects; D008567:Membranes, Artificial; D008954:Models, Biological; D018384:Oxidative Stress / Q000187:drug effects; D010100:Oxygen / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism
D000578:Amidines; D000975:Antioxidants; D062385:Hydroxybenzoates; D008567:Membranes, Artificial; D017382:Reactive Oxygen Species; C046728:2,2'-azobis(2-amidinopropane); D020169:Caspases; C017616:phenolic acid; D010100:Oxygen