Inhibitory effects of cadmium on peripheral blood mononuclear cell proliferation and cytokine release are reversed by zinc and selenium salts.
Zinc (Zn) and selenium (Se) exert regulatory activities on immune functions, while cadmium (Cd) is an immunotoxic agent. The object of this study was to detect effects of 10(-4), 10(-5), and 10(-6) M Cd sulphate, Zn sulphate, and sodium selenite, and their combinations on human peripheral blood mononuclear cell (PBMC) proliferation and IFN-gamma and TNF-alpha production. Only 10(-5) M Zn sulphate significantly enhanced spontaneous PBMC proliferation, which was unaffected by the other salts. At 10(-4) and 10(-5) M, Cd sulphate exerted a dose-response inhibitory action on phytohemagglutinin- (PHA-) stimulated PBMC proliferation and cytokine release, while 10(-4) M and 10(-5) M Zn sulphate and 10(-5) M sodium selenite induced a stimulatory effect on both proliferation and cytokine release; 10(-4) M sodium selenite enhanced only the PBMC proliferation; at 10(-6) M, none of the salts changed the PHA-stimulated immune activity. Moreover, 10(-4) and 10(-5) M Zn and 10(-5) M Se strongly upregulated IFN-gamma (a Th1 cytokine) release, even in presence of 10(-5) M Cd, and reduced the inhibitory effects of Cd on PBMC proliferation and TNF-alpha release. This study confirms that Zn and Se both strongly enhance cytokine release induced by mitogenic stimulation, showing also that Zn acts with a broader range of concentrations than Se. This suggests that dietary excess of Se may not have beneficial effects.
Boscolo
Paolo
P
Department of Medicine and Sciences of Ageing, University G. D'Annunzio, Chieti, Italy. boscolo@unich.it
Di Giampaolo
Luca
L
Qiao
Niu
N
Reale
Marcella
M
Castellani
Maria Luisa
ML
Lucci
Isabella
I
Travaglini
Paola
P
Kouri
Mary
M
Verna
Nicola
N
Volpe
Anna Rita
AR
Carmignani
Marco
M
Paganelli
Roberto
R
Di Gioacchino
Mario
M
D019187:Cadmium Compounds / Q000633:toxicity*; D049109:Cell Proliferation / Q000187:drug effects; D016207:Cytokines / Q000096:biosynthesis*; D006801:Humans; D066298:In Vitro Techniques; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D018038:Sodium Selenite / Q000494:pharmacology*; D013431:Sulfates / Q000633:toxicity*; D019287:Zinc Sulfate / Q000494:pharmacology*
D019187:Cadmium Compounds; D016207:Cytokines; D013431:Sulfates; D019287:Zinc Sulfate; C037123:cadmium sulfate; D018038:Sodium Selenite