Close association of intestinal autofluorescence with the formation of severe oxidative damage in intestine of nematodes chronically exposed to Al2O3-nanoparticle

In nematodes, acute exposure (24-h) to 8.1–30.6 mg/L Al2O3-nanoparticles (NPs) or Al2O3 did not influence intestinal autofluorescence, whereas chronic exposure (10-d) to Al2O3-NPs at concentrations of 8.1–30.6 mg/L or Al2O3 at concentrations of 23.1–30.6 mg/L induced significant increases of intestinal lipofuscin accumulation, and formation of severe stress response and oxidative damage in intestines. Moreover, significant differences of intestinal autofluorescence, stress response and oxidative damage in intestines of Al2O3-NPs exposed nematodes from those in Al2O3 exposed nematodes were detected at examined concentrations. Oxidative damage in intestine was significantly correlated with intestinal autofluorescence in exposed nematodes, and oxidative damage in intestine was more closely associated with intestinal autofluorescence in nematodes exposed to Al2O3-NPs than exposed to Al2O3. Thus, chronic exposure to Al2O3-NPs may cause adverse effects on intestinal lipofuscin accumulation by inducing the formation of more severe oxidative stress in intestines than exposure to Al2O3 in nematodes.

► We examined chronic toxicity of Al2O3-nanoparticles (NPs). ► Al2O3-NPs exposure induced intestinal lipofuscin accumulation. ► Al2O3-NPs exposure caused forming stress response and oxidative damage in intestines. ► Oxidative stress may induce chronic Al2O3-NPs toxicity in intestine of nematodes.