Lauren Petrick, Mira Rosenblat, Mickey Aviram
Nanoparticle research has focused on their toxicity in general, while increasing evidence points to additional specific adverse effects on atherosclerosis development. This research looks at the atherogenic effects of amorphous SiO2 nanoparticles on lipoproteins and a cultured macrophages system (J774.1 murine cell line) as models for foam cell formation, the hallmark of early atherogenesis. Following incubation with SiO2 nanoparticle (SP, d=12 nm, 0-20 µg/mL), increased cytotoxicity (via increased apoptosis) and oxidative stress was observed compared to control cells. Furthermore, SiO2 exposure resulted in increased TG accumulation in macrophages (compared to control cells). The TG accumulation didn’t result from a decrease in TG cell secretion or due to an increased TG biosynthesis rate, but from attenuated TG hydrolysis, secondary to decreased lipase activity and hormone sensitive lipase (HSL) and the expression of adipose triglyceride lipase (ATGL) protein. A manuscript reporting these results has been recently accepted for publication in Toxicology and Industrial Health.