Acute cadmium administration to rats exerts both immunosuppressive and proinflammatory effects in spleen
2014
Authors:
Demenesku, JelenaMirkov, Ivana
Ninkov, Marina
Popov Aleksandrov, Aleksandra
Zolotarevski, Lidija
Kataranovski, Dragan S.
Kataranovski, Milena
Document Type:
Article (Published version)
Metadata
Show full item recordAbstract:
Conflicting data (both suppression and augmentation as well as lack of
the effect) exist in respect to cadmium (Cd) and splenic T cell-based
immune cell activity. Spleen is also the site of innate immune responses
but impact of Cd on this type of immunity has been less explored. In the
present study the effects of acute Cd administration on basic aspects of
both T cell-based and innate immune spleen cell activity were examined
in rats. Intraperitoneal injection of 1 mg of Cd/kg resulted in decrease
in concanavalin A (ConA) induced proliferation which seems to be more
related to altered spleen cells responsiveness to IL-2 than to
apoptosis. Differential effects on proinflammatory T cell derived
cytokines were observed (decreases of IFN-gamma gene expression and
ConA-stimulated production, but increases in IL-17 mRNA levels with no
effect on concentrations of protein product). Reduction of IFN-gamma
production seemed not to rely on IL-4 and IL-10, but at least partly on
nitric oxide (NO). Increased activity relevant for innate immunity
(granulocyte and CD11b(+) cell accumulation in the spleen, inducible
nitric oxide synthase/iNOS expression and NO production by spleen cells)
was observed, but there was a decrease in respiratory burst
(dihydrorhodamine/DHR oxidation and nitroblue tetrazolium/NBT
reduction). Increases of TNF-alpha and IL-1 beta gene expression and
IL-1 beta protein product were noted as well. Administration of 0.5 mg
Cd/kg resulted in less pronounced (ConA-induced proliferation) or lack
of the effect (IFN-gamma production) on spleen T cell activities and on
innate activities (granulocyte accumulation, NO production) as well.
However, increases of spleen cell respiratory burst activity and IL-1
beta production were observed. Effects of lower cadmium doses (5 ppm and
50 ppm) on several aspects of spleen cell immune activity were observed
in intermediate period of exposure (30 days, oral intake) as well.
Differential effects of Cd on immune activities of spleen cells might
contribute to our understanding of the complexity of immunomodulatory
effects of this metal. (C) 2014 Elsevier Ireland Ltd. All rights
reserved.
Keywords:
Cadmium; Rats; Spleen; Inflammatory cytokines; T cell activity; Innate immunitySource:
Toxicology, 2014, 326, 96-108
DOI: 10.1016/j.tox.2014.10.012
ISSN: 0300-483X