Aroclor 1254 exposure reduces disease resistance and innate immune responses in fasted Arctic charr

Abstract

To examine the immunological impacts of polychlorinated biphenyls (PCBs) in an environmentally relevant way, we orally contaminated Arctic charr (Salvelinus alpinus) with Aroclor 1254. After contamination, fish were either fed (0 and 100 mg Aroclor 1254 kg(-1) fish wt) or fasted (0, 1, 10, and 100 mg kg(-1)) to mimic cycles of feeding-fasting experienced by Arctic animals. After four months, PCB concentrations in muscle were the same in fasted and fed fish; however, PCBs in kidneys of fed fish were 33 to 50% of those in fasted fish. Arctic charr were exposed to Aeromonas salmonicida, the bacteria responsible for furunculosis, by cohabitation with infected conspecifics. Fasted fish had a significant trend toward lower survival with higher dose of PCBs--from 68% in controls to 48% in treatment involving 100 mg kg(-1). Independent of PCB contamination, fed fish had the lowest survival; we attribute this to stress associated with establishing and maintaining feeding hierarchies. A significant decrease in the activity of lysozyme was observed in skin mucus, as was hemagglutination ability of a putative rhamnose lectin in fasted, but not in fed, PCB-treated fish. These results demonstrate the immunosuppressive effects of PCBs on Arctic charr, and they illustrate the importance of considering environmentally relevant nutritional status in ecotoxicological studies.

Tissue-specific molecular immune response to lipopolysaccharide challenge in emaciated anadromous Arctic charr

“…This supports our previous finding that resistence toward furunculosis was not compromised by extended fasting in Arctic charr (Maule et al, 2005). This is a unique adaptation as even short-term fasting in animals, including mammals and fish, reduced the capacity for immune response activation (Wing et al, 1988;Pires et al, 2007;Caruso et al, 2011;Martin et al, 2010).We propose that maintenance of immune competence in Arctic charr despite extended fasting as an adaptive trait that arose along with their anadromous life-strategy, preparing the emaciated animals to defend against pathogenic challenges when they migrate from fresh water to seawater.…”

The effects of estrogenic and androgenic endocrine disruptors on the immune system of fish: a review

“…bacteria. Exposure to PCB via the diet caused a decrease in lysozyme enzymatic activity in the mucus of Arctic charr, Salvelinus alpinus (Maule et al 2005). Taken together, these studies suggest that estrogen-like EDCs depress immune proteins.…”

Immunotoxic and cytotoxic effects of atrazine, permethrin and piperonyl butoxide to rainbow trout following in vitro exposure

“…Immunotoxicity in fish has been demonstrated for a wide range of chemical classes including polycyclic aromatic hydrocarbons (PAHs) [2], polychlorinated biphenyls (PCBs) [3] and some pesticides [4]. However, for many pesticides, the potential for immunotoxicity in exposed fish has been largely unexplored or data is very limited.…”