The Dieni Research Group attends and presents at the CSZ 2013 Annual Meeting

Chris and Neal Callaghan have both attended and presented at the Canadian Society of Zoologists (CSZ) 2013 Annual Meeting hosted at the University of Guelph. The CSZ is a national-level society of scientists working on animal-related research in the fields of 1) comparative biochemistry and physiology, 2) parasitology, immunity and environment, 3) comparative morphology and development, and 4) ecology, ethology and evolution. Their annual meeting is a highly-attended conference with people from across Canada (and around the world) congregating for a week-long exchange of ideas and fun.

Chris had the opportunity to deliver an oral presentation entitled “In vitro approaches to understanding the basis of gold nanoparticle toxicity in animals.” Neal presented a poster entitled “Markers of Oxidative Stress in Livers of Zinc Oxide Nanoparticle-Treated White Sucker Fish.” This poster had previously been selected as a finalist for both the Battle Award and the Holeton Award. Neal had also received several student travel awards to attend this meeting including: 1) a departmental travel award, 2) a students’ union travel award, and 3) an EPCOR Water Ltd student travel award.

Tyson MacCormack also delivered an oral presentation entitled “Getting to the heart (and gills) of  nanotoxicology: cardiorespiratory toxicity of commercially relevant nanoparticles” which listed Chris and Neal among its contributors.

Below are abstracts taken from the CSZ Bulletin for Chris, Neal, and Tyson’s presentations, respectively. Well done everyone!

In vitro approaches to understanding the biochemical basis of gold nanoparticle toxicity in animals
Approches in vitro pour comprendre les bases biochimiques de la toxicité des nanoparticules d’or chez les animaux
1Christopher A. Dieni, 1Christopher J.L. Stone, 1M. Luke Armstrong, 1Neal I. Callaghan, 1Tyson J. MacCormack
1Mount Allison University
The increase in industrial and commercial uses of nanoparticles (NPs) has led to a rise in their release into the environment, resulting in the exposure of native species to NPs and their associated bioactivities. While numerous whole-organism studies have revealed that NPs induce a toxic response on a systemic level, the exact mechanisms by which they exert their effects on a biochemical level is largely yet to be determined. The purpose of this study was to characterize the effects of gold NPs on animal proteins in vitro, in an effort to elucidate the biochemical mechanisms of toxicity on a simpler scale. Bovine serum albumin (BSA) was used as model protein for assays involving NP-protein interactions. Albumin is a serum protein chiefly responsible for transporting lipids and fatty substances through blood plasma, and thus any deleterious albumin-NP interactions seen in this model could potentially disrupt global lipid metabolism in vivo.

Markers of oxidative stress in zinc oxide nanoparticle-treated white sucker fish (Catostomus commersonii)
Marqueurs du stress oxydatif chez des meuniers noirs (Catostomus commersonii) exposés aux nanoparticules d’oxyde de zinc
1Neal Callaghan, 1Christopher Dieni, 1Kathryn Butler, 1Tyson MacCormack
1Mount Allison University
Nanoparticles, an increasingly-prevalent product of industrial and consumer processes, are commonly introduced to the environment where they interact with local species. A common mechanism of nanoparticle-induced toxicity is the creation of reactive oxygen species (ROS), which cause oxidative stress-associated damage in organisms by nonspecific oxidation of cellular components. This is especially prominent in fish, which use gills to uptake oxygen, thereby concentrating nanoparticles in filament tissue before distributing them systemically. The levels of common markers of oxidative stress, including TBARS, glutathione, and oxidation-dependent enzymes were assessed in zinc oxide nanoparticle (nZnO)-exposed and control white sucker fish. The findings of this survey allow us to better define a model of nanoparticle-induced toxicity in aquatic organisms.

Getting to the heart (and gills) of nanotoxicology: cardiorespiratory toxicity of commercially relevant nanoparticles
Le coeur (et les branchies) de la nanotoxicologie: Toxicité cardiorespiratoire de nanoparticules utilisées commercialement
1Tyson MacCormack, 1Kathryn Butler, 1Alexandra Blay, 1Neal Callaghan, 1Christopher Dieni
1Mount Allison University
Mammals exhibit a stereotyped cardiorespiratory response to air pollution. Inhalation of nanoparticulate contaminants leads to the development of systemic oxidative stress and long-term cardiovascular morbidity. Water breathing animals are now being exposed to detectable levels of engineered nanoparticles but it is not known whether
particulate contaminants exert such effects in aqueous systems. To address this question, white sucker, Catostomus commersonii, were fitted with electrocardiography electrodes and exposed to commercially relevant ZnO nanoparticles (~30 nm diameter, 1 mg/L) for 24 h. Both Na+/K+-ATPase activity and markers of oxidative stress were significantly elevated in gill tissue, suggesting that ZnO nanoparticles compromise the integrity of the epithelium. Cardiovascular parameters were also altered in nanoparticle-treated fish, likely as a result of systemic oxidative stress. The results indicate that nanoparticles may cause chronic, sub-lethal toxicity in fish and the
mechanisms linking inhalation to cardiac morbidity appear similar to those observed in air-breathing vertebrates.