Toxicity of PAMAM dendrimers to Chlamydomonas reinhardtii

Petit, Anne-Noëlle; Eullaffroy, Philippe; Debenest, Timothée; Gagné, François

doi:10.1016/j.aquatox.2010.01.019

Cited by 51 publications

(18 citation statements)

References 60 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Highest growth stimulation was recorded at 5 lg cypermethrin l -1 , coincident with the highest soluble protein and SOD activity detected. The simulative effects on microalgae growth under low concentrations of organic compounds were also observed by many other authors (Prado et al 2009;Sahinkaya and Dilek 2009;Gustafsson et al 2010;Petit et al 2010) and in our previous study in single-species exposure (Wang et al 2010a).…”

Section: Mechanistic Response For Low-dose Effectssupporting

confidence: 71%

Toxicological effects of cypermethrin to marine phytoplankton in a co-culture system under laboratory conditions

2011

View full text Add to dashboard Cite

The growth of three marine phytoplankton species Skeletonema costatum, Scrippsiella trochoidea and Chattonella marina and the response of the antioxidant defense system have been investigated on exposure to commercial cypermethrin for 96 h and 32 days in a co-culture system. Growth of the three species was generally comparable over 96 h with an inoculation of 1:3:6.5 (C. marina:S. trochoidea:S. costatum), with stimulation at 5 μg l(-1) and inhibition under higher concentrations (50, 100 μg l(-1)). However, when inoculating at ratios of 1:1:1 during a 32 day test, S. costatum became the most sensitive species and was significantly inhibited in all test groups under the dual stresses of cypermethrin and interspecies competition. The growth of C. marina was significantly inhibited at the concentrations higher than 5 μg l(-1), while the growth of S. trochoidea was significantly promoted at low concentrations. Superoxide dismutase (SOD) activities significantly increased during 6-12 h exposure periods in test treatments at low concentrations, and enhanced in the control as well due to interspecies competition. The lipid peroxidation product malondialdehyde was enhanced at high concentrations, but did not increase in control and low concentration cultures with high SOD activities, indicating that algal cells activated the antioxidant enzymes promptly to protect the cells from lipid membrane damage. Results from this study suggested that cypermethrin pollution in maricultural sea waters might lead to a shift in phytoplankton community structure from diatom to harmful dinoflagellate species, and thus potentially stimulatory for harmful algal blooms.

show abstract

Section: Mechanistic Response For Low-dose Effectssupporting

confidence: 71%

Toxicological effects of cypermethrin to marine phytoplankton in a co-culture system under laboratory conditions

2011

View full text Add to dashboard Cite

show abstract

“…However, V. fischeri sensitivity to AuG0 NPs was in the same range as previously found for PAMAM dendrimers (EC50 values of 0.04-0.18 mg mL 21 ; Mortimer et al, 2008;Naha et al, 2009). Lower EC50 values (0.003-0.005 mg mL 21 ) were found for G4 and G5 PAMAM dendrimers in C. reinhardtii after 72 h of treatment (Petit et al, 2010); however, this lower EC50 value for PAMAM may be explained by the longer exposure time, as in our study, the increase in the exposure time from 30 min to 24 h resulted in a 27% decrease of EC50 value (see Table I). Therefore, the difference of toxicity between AuG0 NPs and PAMAM dendrimers appears to be more important in mammalian cells.…”

Section: Discussionsupporting

confidence: 82%

Toxicity of pamam-coated gold nanoparticles in different unicellular models

et al. 2012

View full text Add to dashboard Cite

Polyamidoamine (PAMAM) dendrimers are used for many pharmaceutical and biomedical applications. However, the toxicological risks of several PAMAM-based compounds are still not fully evaluated, despite evidences of PAMAM deleterious effects on biological membranes, leading to toxicity. In this report, we investigated the toxicity of generation 0 PAMAM-coated gold nanoparticles (AuG0 NPs) in four different models to determine how different cellular systems are affected by PAMAM-coated NPs. Toxicity was evaluated in two mammalian cell lines, Neuro 2A and Vero, in the green alga Chlamydomonas reinhardtii and the bacteria Vibrio fischeri. AuG0 NP treatments reduced cell metabolic activity in algal and bacterial cells, measured by esterase enzymatic activity (C. reinhardtii) and luminescence emission (V. fischeri). EC50 value after 30 min of treatment was similar in both organisms, with 0.114 and 0.167 mg mL(-1) for C. reinhardtii and V. fischeri, respectively. On the other hand, AuG0 NPs induced no change of mitochondrial activity in mammalian cells after 24 h of treatment to up to 0.4 mg mL(-1) AuG0 NPs. Change in the absorption spectra of AuG0 NP in the mammalian cell culture media may indicate an alteration of NP properties that contributed to the low toxicity of AuG0 NPs in mammalian cells. For a safe development of PAMAM-based nanomaterials, the difference of sensitivity between mammalian and microbial cells, as well as the modulation of NPs toxicity by medium properties, should be taken into account when designing PAMAM NPs for applications that may lead to their introduction in the environment.

show abstract

“…Another factor that indirectly inhibition of NMs effects is the production of reactive oxygen species (ROS) by nanoparticles, which can cause chemically-induced toxicity (Petit et al, 2010). The generation of ROS is a consequence of the physical structure and reactive surface chemistry of very small particles.…”

Section: Discussionmentioning

confidence: 99%