Oxidative stress profiles in brain point out a higher susceptibility of fish to waterborne divalent mercury compared to dietary organic mercury

MARINE POLLUTION BULLETIN

卷:122

Article

Cardoso, Olivia^1,2  Puga, Sonia^3,4  Brandao, Fatima^5,6  Canario, Joao⁷  O'Driscoll, Nelson J.⁸  Santos, Maria Ana^1,2  Pacheco, Mario^1,2  Pereira, Patricia^1,2 

[1] Univ Aveiro, Dept Biol, P-3810193 Aveiro, Portugal

[2] Univ Aveiro, CESAM, P-3810193 Aveiro, Portugal

[3] Univ Minho, Life & Hlth Sci Res Inst IGVS, Sch Med EM, Campus Gualtar, P-4750057 Braga, Portugal

[4] ICVS 3Bs PT Govt Associate Lab, Braga, Portugal

[5] Portuguese Natl Inst Hlth, Dept Environm Hlth, Oporto, Portugal

[6] Univ Porto, ISPUP EPI Unit, Rua Taipas 135, P-4050600 Oporto, Portugal

[7] Univ Lisbon, Ctr Quim Estrutural, Inst Super Tecn, Ave Rovisco Pais, P-1049001 Lisbon, Portugal

[8] Acadia Univ, Dept Earth & Environm Sci, Ctr Analyt Res Environm, KC Irving Ctr, Wolfville, NS, Canada

关键词: Inorganic mercury;    Methylmercury;    Neurotoxicity;    Oxidative stress;    Brain;    Fish;   

DOI  :  10.1016/j.marpolbul.2017.06.029

来源: Elsevier

【 摘 要 】

This study examines, for the first time, the neurotoxicity of Hg(II) and MeHg in fish (Diplodus sargus) in a time course comparative perspective and considering realistic exposure levels and routes. Both forms followed an identical time-variation pattern of accumulation in the brain, but dietary MeHg was more efficiently transported to the brain. MeHg was substantially eliminated from the brain in 28 days of depuration, which did not occur for Hg(II). Moreover, Hg(II) displayed a high neurotoxicity potential, as unveiled by the poor activation of brain antioxidant defenses and recurrent oxidative damage (as protein oxidation), while the opposite was recorded upon MeHg exposure. These results highlight the need to include Hg(II) in future environmental health assessment plans, preventing an underestimation of the risk for wild fish populations, which has probably been occurring due to the long-standing idea of the higher toxicity of MeHg in comparison with inorganic Hg forms.

【 授权许可】

Free