Silica nanoparticles enhance germ cell apoptosis by inducing reactive oxygen species (ROS) formation in <i>Caenorhabditis elegans</i>

Abstract

Silica nanoparticles (SiO 2 NPs) are widely used in daily life and can enter organisms through several pathways, often causing unpredictable toxicity. Although SiO 2 NPs are known to cause damage to the respiratory system, little is known about their oral toxicity, and their potential harm to the reproductive system is unclear. In this study, we used a Caenorhabditis elegans model to clarify SiO 2 NPs oral toxicity in vivo and explore their effect on the reproductive system. We exposed C. elegans to 0.25, 0.5 and 1 mg /mL SiO 2 NPs for 24 hr. Our results showed that SiO 2 NPs exposure for 24 hr did not affect nematode survival rates, but did affect, to varying degrees, the reproduction, development, and movement of nematodes, with nematode fecundity being the most sensitive to SiO 2 NPs toxicity. The NPs exposed group showed enhanced germ cell apoptosis and increased oxidative stress as seen through an increase in ROS and malondialdehyde (MDA), and decrease in reduced glutathione (GSH). N-acetyl-L-cysteine (NAC), an antioxidant, negated SiO 2 NPs effect on germ cells and restored nematodes reproductive ability. We also found that SiO 2 NPs could affect the expression of genes related to metal detoxification, oxidative stress, and apoptosis. The expression of metallothionein coding genes mtl-1 and mtl-2 changed most significantly among the tested genes. We demonstrated that SiO 2 NPs could enhance germ cell apoptosis by inducing oxidative stress, providing a new area for studies of the mechanism of SiO 2 NP toxicity.

Nematode surface functionalization with hydrogel sheaths tailored in situ

“…The viability of C. elegans and A. simplex was investigated by monitoring the viability of the nematodes before and after BAM-HRP coating and post-hydrogel sheath coating. The viability of nematodes was determined based on the movement response following mechanical or touch stimuli [ [39] , [40] , [41] ].…”

Toxicity Assessment of SiO2 and TiO2 in Normal Colon Cells, In Vivo and in Human Colon Organoids

“…SiO 2 and TiO 2 nanoparticles can also induce cytotoxicity and thus may have a negative health impact. These studies have shown that SiO 2 and TiO 2 nanoparticles show toxicity in the human lung, intestinal cells and during in vivo experiments [14][15][16][17][18][19].…”

Polystyrene nanoplastics mediated the toxicity of silver nanoparticles in zebrafish embryos

“…To date, the knowledge regarding the carrier effects of microplastics is mainly focused on persistent organic pollutants, heavy metals, and pharmaceuticals. Study on the interactions between microplastics and engineered nanomaterials is still limited, though both of them are constantly released into the aquatic environment through similar pathways, including wastewater, facility agriculture, and landfill (Gautam and Tiwari, 2020;Zhang et al, 2020).…”