The neotropical fish Prochilodus lineatus has been

The neotropical fish Prochilodus lineatus has been widely used in experimental designs for being sensitive to variations in water quality and tolerant to laboratory conditions (Camargo and Martinez, 2006, Cazenave et al., 2014, da Silva and Martinez, 2014, Vieira et al., 2016). Concern and reports about toxicity mechanism related to AgNP exposures have risen through the years; however assays that include aquatic organisms exposed to chronic conditions remain scarce. Massarsky et al. (2014) considered essential to predict environmental concentrations and thus the risk associated with AgNP. In order to contribute to the understanding of their potential toxicity, the aim of this study was to analyze multiple responses in gills of a neotropical fish (Prochilodus lineatus) exposed to sublethal AgNP concentrations.
Materials and methods
Results
Discussion
Conclusions As result of the wide AgNP benefits, principally due to their antibacterial proprieties, their production, use, and deposition in environment are exponentially increasing. Thus, in vivo assays that contribute to a better understanding of the impact generated by nanoparticles are valuable. According to our results, native species such as Prochilodus lineatus and subchronic exposure conditions to low concentrations of AgNP provided relevant information about the toxic effects generated by AgNP. This study also corroborated the importance of using fish as test species for their sensitivity to xenobiotics, and focused on the gill as a target organ for evaluating toxicity mechanisms. AgNP resulted widely biocumulative, disruptive for the antioxidant defense system, and caused damage to cox-2 and histophatologies, as well as led to the proliferation of mucus cells. Different harmful effects have been analyzed at both short and subchronic times of exposures, so we highlight the importance of using a large amount of biomarkers and relevant AgNP concentrations while toxicity approach is attempted. Additional studies that include chronic and sublethal conditions of AgNP exposure, and the evaluation of other relevant biomarkers such as glutathione levels (among other non enzymatic parameters), mucus cells Ag uptake, and ionic disruption should be develop in further studies. We consider this report as relevant in order to contribute to a better understanding about how this emerging pollutant is affecting environments.
Introduction Gentamicin, an aminoglycoside antibiotic is used as an effective agent against gram negative infections. Its chemical stability, rapid bactericidal action has made it a first-line drug in a variety of clinical situations (Ali, 2003). However, nephrotoxicity is the major side effect of aminoglycosides accounting for 10–15% of all cases of acute renal failure (Shifow et al., 2000). Studies have also shown that 30% of the patients treated with gentamicin for more than 7 days show signs of nephrotoxicity (Mattew, 1992). It has been shown that the specificity of gentamicin renal toxicity is related to its preferential accumulation in the renal convoluted tubules and lysosomes (Nagai and Takano, 2004). The mechanism of gentamicin-induced nephrotoxicity is not completely known. However, studies have implicated reactive oxygen species particularly superoxide anion radical in the pathophysiology of gentamicin nephropathy (Cuzzocrea et al., 2002). It has been demonstrated that gentamicin administration increases renal cortical lipoperoxidation, renal nitric oxide generation and mitochondria H2O2 generation (Yang et al., 1995, Parlakpinar et al., 2005). The value and utility of gentamicin in clinical practice would be greatly increased if some means could be found to protect the kidney from undesirable side effects. Thus, a potential therapeutic approach to protect or reverse renal gentamicin damage would have very important clinical consequences (Pedraza-Chaverri et al., 2000, Nagai and Takano, 2004).