Organ-Specific and Size-Dependent Ag Nanoparticle Toxicity in Gills and Intestines of Adult Zebrafish

Abstract

We studied adult zebrafish to determine whether the size of 20 and 110 nm citrate-coated silver nanoparticles (AgC NPs) differentially impact the gills and intestines, known target organs for Ag toxicity in fish. Following exposure for 4 h, 4 days, or 4 days plus a 7 day depuration period, we obtained different toxicokinetic profiles for different particle sizes, as determined by Ag content of the tissues. Ionic AgNO3 served as a positive control. The gills showed a significantly higher Ag content for the 20 nm particles at 4 h and 4 days than the 110 nm particles, while the values were more similar in the intestines. Both particle types were retained in the intestines even after depuration. These toxicokinetics were accompanied by striking size-dependent differences in the ultrastructural features and histopathology in the target organs in response to the particulates. Ag staining of the gills and intestines confirmed prominent Ag deposition in the basolateral membranes for the 20 nm but not for the 110 nm particles. Furthermore, it was possible to link the site of tissue deposition to disruption of the Na(+)/K(+) ion channel, which is also localized to the basolateral membrane. This was confirmed by a reduction in ATPase activity and immunohistochemical detection of the α subunit of this channel in both target organs, with the 20 nm particles causing significantly higher inhibition and disruption than the larger size particles or AgNO3. These results demonstrate the importance of particle size in determining the hazardous impact of AgNPs in the gills and intestines of adult zebrafish.

Low molecular weight chitosan-coated silver nanoparticles are effective for the treatment of MRSA-infected wounds

“…[19][20][21] The cytotoxicity of AgNPs could be influenced by particle size, surface-stabilizing agents, pH, and some other factors. 1,5,7,[22][23][24] The surface-stabilizing coating is one of the most important factors for protecting cell viability from AgNPs. [25][26][27] Previous studies have shown that chitosan has a very good biocompatibility and antibacterial properties.…”

Intrinsic functional and architectonic heterogeneity of tumor-targeted protein nanoparticles

“…Far than chemical composition, size and shape are crucial factors determining the relationships between nanoparticles and increasingly complex biological systems (namely from cells to entire organisms) in critical aspects such as organ specificity and biodistribution [36][37][38][39][40], toxicity [41], and cell uptake and fate [39,[42][43][44][45]. Although previously checked in several types of nanostructures, mainly in crystalline nano-and micromaterials, the present study is the first evaluation of form (geometry) and function (cellular uptake) of protein nanoparticle populations.…”

Aquatic Ecotoxicity Testing of Nanoparticles—The Quest To Disclose Nanoparticle Effects

“…The 20 nm Ag ENPs gained access to the basolateral membrane, whereas both 110 nm Ag ENPs and the ions were confined to the apical membrane 122. Differences were also observed in gill tissue, where Ag ENPs were mainly located on the secondary filaments, whereas Ag was mostly present in the primary filaments of zebrafish exposed to the ionic control 122. This highlights the need to account for differences in the internalization and translocation on the basis of the size of ENPs and also compared to a dissolved control.…”