Intraperitoneal Exposure to Nano/Microparticles of Fullerene (C60) Increases Acetylcholinesterase Activity and Lipid Peroxidation in Adult Zebrafish (Danio rerio) Brain

Abstract

Even though technologies involving nano/microparticles have great potential, it is crucial to determine possible toxicity of these technological products before extensive use. Fullerenes C60 are nanomaterials with unique physicochemical and biological properties that are important for the development of many technological applications. The aim of this study was to evaluate the consequences of nonphotoexcited fullerene C60 exposure in brain acetylcholinesterase expression and activity, antioxidant responses, and oxidative damage using adult zebrafish as an animal model. None of the doses tested (7.5, 15, and 30 mg/kg) altered AChE activity, antioxidant responses, and oxidative damage when zebrafish were exposed to nonphotoexcited C60 nano/microparticles during 6 and 12 hours. However, adult zebrafish exposed to the 30 mg/kg dose for 24 hours have shown enhanced AChE activity and augmented lipid peroxidation (TBARS assays) in brain. In addition, the up-regulation of brain AChE activity was neither related to the transcriptional control (RT-qPCR analysis) nor to the direct action of nonphotoexcited C60 nano/microparticles on the protein (in vitro results) but probably involved a posttranscriptional or posttranslational modulation of this enzymatic activity. Taken together these findings provided further evidence of toxic effects on brain after C60 exposure.

Preliminary safety assessment of Eudragit® polymers nanoparticles administration in the rat brain

“…Previous studies have provided evidence that nanoparticles have different effects on AchE activity. For example, metal oxide ones induced an inhibition of this activity (Xia et al, 2013), while fullerene C60 increased it (Dal Forno, 2013). The present findings indicated that a single dose of EUD-NPs (50 mg/kg b.w) given either orally or IP increased AChE activity after different time of exposure in either oral or I.P injected rats.…”

“…This was achieved by measuring the oxidative stress parameters in the forebrain, midbrain and hindbrain regions which is recognized as tool to evaluate toxicity mediated by small particles exposure. In addition, the effect of EUD-NPs on the cholinergic activity was estimated by assessing the acetylcholinesterase activity as a biomarker of exposure to neurotoxic compounds (Dal Forno, 2013) as well as the histological changes in the three selected brain regions.…”

Photodynamic therapy with decacationic [60]fullerene monoadducts: Effect of a light absorbing electron-donor antenna and micellar formulation

“…Similarly, there is some concern about the in vivo toxicity of C 60 and other fullerenes. For example, some C 60 derivatives were reported to be highly toxic 52, 53 . Encapsulating these fullerenes may be a good alternative to reduce their in vivo toxicity.…”

Autorregulação e riscos: desafios e possibilidades jurídicos para a gestão dos resíduos nanoparticulados

“…Portanto, um dos pontos que merece destaque, considerando o cenário analisado até o momento, se refere à juridicização dos riscos. Há evidências científicas de que os riscos poderão ser produzidos a partir de múltiplas fontes, como o risco de inalação e permanência profunda nos pulmões, acarretando danos por atravessar membranas biológicas(CHRISTENSEN, 2015); a comprovação de evidências de que os nanotubos de carbono são potencialmente perigosos em ambientes aquáticos, e que o mecanismo de toxicidade é complexo e insuficientemente compreendido até o momento (BRITTO, 2012); outro estudo mostra possíveis efeitos tóxicos no cérebro (neurotoxicidade) dos peixes Zebrafish (Danio rerio) expostos aos nanotubos de carbono (DAL FORNO et al, 2013). Apesar das promessas substanciais da nanotecnologia, se vislumbram várias áreas de preocupação, que motivam os atuais pedidos por regulação.…”