Quercetin inhibits lymphocyte activation and proliferation without inducing apoptosis in peripheral mononuclear cells.
Toxicity of chemotherapeutic drugs towards normal cells is a serious side effect of cancer treatment. Thus, finding of molecules with low toxicity for normal cells is crucial. Several natural compounds, such as flavonoid quercertin, are receiving a growing attention as "chemopreventers". Quercetin kills tumour-derived cell lines, but little is known about its effects on normal cells. Here we show that although quercetin exerts a higher apoptotic potential on leukemic cell lines than on peripheral blood mononuclear cells (PBMCs) and does not sensitize PBMCs to CD95-induced apoptosis, it is able to inhibit normal immune functions such as T cell proliferation and activation. Quercetin sensitivity is independent on cell cycle progression since it was not abrogated in serum-starved U937 cells, nor proliferating PBMCs underwent apoptosis after quercetin treatment. However, quercetin prevented PHA-induced PBMC proliferation and SEB-induced upregulation of activation markers. Our data suggest that quercetin, while incapable of inducing apoptosis in normal cells under several conditions, could interfere with effector T cell function.
Lugli
Enrico
E
Department of Biomedical Sciences, Chair of Immunology, University of Modena and Reggio Emilia, via Campi 287, 41100 Modena, Italy.
Ferraresi
Roberta
R
Roat
Erika
E
Troiano
Leonarda
L
Pinti
Marcello
M
Nasi
Milena
M
Nemes
Elisa
E
Bertoncelli
Linda
L
Gibellini
Lara
L
Salomoni
Paolo
P
Cooper
Edwin L
EL
Cossarizza
Andrea
A
D017209:Apoptosis / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects*; D005434:Flow Cytometry; D006801:Humans; D016130:Immunophenotyping; D008213:Lymphocyte Activation / Q000187:drug effects*; D011794:Quercetin / Q000494:pharmacology*; D020298:U937 Cells
D011794:Quercetin