Acute toxicity of manganese in goldfish Carassius auratus is associated with oxidative stress and organ specific antioxidant responses

Effect of polychlorinated biphenyls on oxidation stress in the liver of juvenile GIFT, Oreochromis niloticus

“…CAT and GPx can act cooperatively as scavengers of H 2 O 2 and other hydroperoxides. Vieira et al (2012) reported that the decreased CAT activity was concomitant with stimulated SOD and GPx activity in goldfish under acute toxicity following manganese exposure. GPx showed significant changes in the current study (1.16-and 1.17-fold for 0.5 and 5 mg/L PCB-exposure groups, respectively).…”

Effects of manganese on fat snook Centropomus parallelus (Carangaria: Centropomidae) exposed to different temperatures

“…Impacts on hematology (Agrawal, Srivastava, 1980;Wepener et al, 1992), immunomodulation (Cossarini-Dunier et al, 1988;Hernroth et al, 2004), and hormonal interference (Hoseini et al, 2004) can also occur. Other damages on the metabolic system were also observed, such as impacts on carbohydrate metabolism (Nath, Kumar, 1987;Barnhoorn et al, 1999;Partridge, Lymbery, 2009) and alterations to the antioxidant system (Falfushynska et al, 2011;Vieira et al, 2012;Dolci et al, 2013;Gabriel et al, 2013). However, the use of biochemical and genotoxic endpoints to understand the interaction between water temperature and manganese exposure in fish has not yet been investigated.…”

“…These facts can also lead to increases in the bioavailability of pollutants in the environment and, consequently, the metal uptake rates and their toxicity (Bervoets et al, 1996;Vergauwen et al, 2013;Lee et al, 2014). Manganese (Mn 2+ ) is a constitutive element of a series of essential enzymes and cofactors that are fundamental to brain function, such as glutamine synthetase, superoxide dismutase and others (Yokel, 2009), but it can be very toxic at concentrations above the optimal threshold level (Vieira et al, 2012). In natural waters, dissolved manganese from anthropogenic sources/influences associated with metal mining and other industrial activities may reach very high concentrations (McNeely et al, 1979;Morillo, Usero, 2008).…”

Avaliação da toxicidade de metais no metabolismo de fêmeas vitelogênicas de Astyanax bimaculatus (Teleostei: Characidae)

“…Pouco se sabe sobre os reais efeitos do Mn em peixes, mas alguns estudos demonstraram que sua entrada no organismo se dá como qualquer outro metal, através das brânquias promovendo, alterações funcionais (Nyberg et al, 1995;Vieira, 2012 -capítulo 2). Na sequência o metal é transportado via corrente sanguínea e distribuído para vários órgãos, acumulando-se principalmente em tecidos ricos em mitocôndrias como o fígado, pâncreas e rins (Rouleau et al, 1995 (Jaben et al, 2012;Oberholster et al, 2012).…”

“…Além disso, já foi demonstrado que o Mn altera várias funções fisiológicas tais como redução de potássio e glicogênio no fígado (Barnhoon et al, 1999;Partridge e Lymbery, 2012), hiperglicemia e inibição da liberação de insulina (Nath and Kumar, 1987), estresse oxidativo e peroxidação lipídica (Vieira et al, 2012) o que torna outros órgãos mais susceptíveis ao agente estressor comprometendo suas funções.…”