Efekti oralnog unosa kadmijuma na imunski sistem kože pacova
Effects of oral cadmium intake in skin reactivity in rats
Abstract:
Harmful effects of environmental Cd exposure, which affect different organs, are being increasingly recognized. Although it is known that topical Cd administration may affect skin cell viability, there is a paucity of data concerning Cd effect on the homeostatic processes of this tissue, including effects on the skin's immune system, especially after oral intake. The effects of prolonged exposure (30 days) to the two environmentally relevant Cd doses (5 and 50 ppm) were examined in Dark Agouti (DA) and Albino Oxford (AO) rats, which differ in the immune responses to different stimuli. In addition to the Cd effects on the oxidative and immune/inflammatory skin activity, the reactivity of skin after additional dinitrochlorobenzene (DNCB) stimulus during contact hypersensitivity reaction (CHS), was examined. Despite similar Cd deposition in skin/skin cells, tissue damage and a higher intensity/different pattern of oxidative and immune responses were observed in DA strain already at 5 ppm Cd, indicating a higher sensitivity of this strain to the dermatotoxic Cd effects. Although epidermal cells (ECs) of both strains developed stress response to the Cd presence, a more intensive antioxidative response (an increase of GSH, a higher level of gene expression for MT-1 and MT-2, proteins for Nrf2, as well as the genes of AHR pathway) with the presence of apoptosis only in AO strain, indicates a better protection capability of this strain from deleterious Cd effect. The proinflammatory response was observed only in the ECs of DA strain (an increase in IL-1β, TNF and IL-6), as well as IL-10 increase in AO strain as a potential protection mechanism. Nevertheless, after topical administration of DNCB, an inflammatory response develops in both strains, indicating the breakthrough of protective mechanisms that persisted in AO rats after oral Cd intake (at least at 50 ppm Cd). This study may be useful for examining the relationship between oral Cd intake and different skin sensitivity to the development of inflammatory responses and pathological conditions.
Keywords:
Oral cadmium intakem DA and AO rats; Skin immune system; Epidermal cells; Dermatotoxicity; Contact hypersensitivitySource:
University of Belgrade, Faculty of Biology, 2020, 1-137Funding / projects:
- Immunomodulatory effects of environmental xenobiotics and biotic factors on the populations of mouse-like rodents (RS-MESTD-Basic Research (BR or ON)-173039)