Mechanistic study on the biological effects of silver and gold nanoparticles in Caco-2 cells--induction of the Nrf2/HO-1 pathway by high concentrations of silver nanoparticles.

The most commonly used metal nanoparticles (NPs) across diverse applications, including in agro-food applications, include silver (AgNPs) and gold (AuNPs). In the present study, we aimed to investigate the biological responses and possible toxicological effects of AgNPs and AuNPs in the Caco-2 cells as an in vitro human GI tract model. Both AgNPs and AuNPs were internalized into the cytoplasm of Caco-2 cells, but not within the nucleus and only exposure to high concentrations of AgNPs, but not AuNPs, caused acute cytotoxicity and depolarization of the mitochondrial membrane potential.

Silver nanoparticles induce toxicity in A549 cells via ROS-dependent and ROS-independent pathways.

Silver nanoparticles (AgNPs) are incorporated into a large number of consumer and medical products. Several experiments have demonstrated that AgNPs can be toxic to the vital organs of humans and especially to the lung. The present study evaluated the in vitro mechanisms of AgNP (<100 nm) toxicity in relationship to the generation of reactive oxygen species (ROS) in A549 cells.

Titanium dioxide nanoparticles-mediated in vitro cytotoxicity does not induce Hsp70 and Grp78 expression in human bronchial epithelial A549 cells.

Titanium dioxide nanoparticles (TiO(2)NPs) are increasingly being used in various industrial applications including the production of paper, plastics, cosmetics and paints. With the increasing number of nano-related products, the concern of governments and the general public about the health and environmental risks, especially with regard to occupational and other environmental exposure, are gradually increasing. However, there is insufficient knowledge about the actual affects upon human health and the environment, as well as a lack of suitable biomarkers for assessing TiO(2)NP-induced cytotoxicity.

Canarosine: a new guanidine alkaloid from Canavalia rosea with inhibitory activity on dopamine D1 receptors.

A new acyclic guanidine alkaloid, canarosine (1), together with five known compounds, beta-sitosterol (2), stigmasterol (3), daucosterol (4), epi-inositol 6-O-methyl ether (5), and rutin (6), were isolated from the aerial parts of Canavalia rosea. Their structures were established on the basis of their spectroscopic data. In the radioligand receptor binding assay, canarosine (1), at a concentration of 100 microg/ml, caused 91% inhibition of the dopamine D1 receptor binding with an IC50 value of 39.