Increased Level of α2,6-Sialylated Glycans on HaCaT Cells Induced by Titanium Dioxide Nanoparticles under UV Radiation

Abstract

As one of the most widely used nanomaterials, the safety of nano-TiO2 for human beings has raised concern in recent years. Sialylation is an important glycosylation modification that plays a critical role in signal transduction, apoptosis, and tumor metastasis. The aim of this work was to investigate the cytotoxicity and phototoxicity of nano-TiO2 with different crystalline phases for human skin keratinocytes (HaCaT cells) under ultraviolet (UV) irradiation and detect sialic acid alterations. The results showed that the mixture of crystalline P25 had the highest cytotoxicity and phototoxicity, followed by pure anatase A25, whereas pure rutile R25 had the lowest cytotoxicity and phototoxicity. A25 and R25 had no effects on the expression of sialic acids on HaCaT cells. However, HaCaT cells treated with P25 and UV showed an increased level of alterations in α2,6-linked sialic acids, which was related to the level of reactive oxygen species (ROS) generated by nano-TiO2 and UV. The abundance of α2,6-linked sialic acids increased as ROS production increased, and vice versa. Antioxidant vitamin C (VC) reversed the abnormal expression of α2,6-linked sialic acids caused by nano-TiO2 and protected cells by eliminating ROS. These findings indicate that nano-TiO2 can alter the sialylation status of HaCaT cells under UV irradiation in a process mediated by ROS.

Visible-Light Active Titanium Dioxide Nanomaterials with Bactericidal Properties

“…The degree of photocytotoxicity and cell membrane damage depends greatly on the level of ROS generated. More recently, Ren et al also reported a similar finding on the phototoxicity of TiO 2 NPs in HaCaT cells under UV irradiation [329].…”

<p>Involvement of TGF-β and ROS in G1 Cell Cycle Arrest Induced by Titanium Dioxide Nanoparticles Under UVA Irradiation in a 3D Spheroid Model</p>

“…The size of nano-TiO 2 used in the present study was 25 nm, the characterization of which has been described previously. 8 The crystalline composition was a mixture of rutile and anatase. From day 3 to 7, the cells were seeded in fibrin gels and imaged to evaluate 3D spheroid formation ( Figure 1A).…”

“…Nano-TiO 2 with photoreactivity under UVA irradiation induce significant cell damage, lipid peroxidation, and overexpression of glycans, which leads to phototoxic reactions. [6][7][8] Nano-TiO 2 induce normal liver cell apoptosis by triggering the production of a large amount of reactive oxygen species (ROS) under UVA irradiation, resulting in upregulation of the death receptor, Fas, and Bax. 1 Despite the plethora of research regarding the phototoxicity of nano-TiO 2 in vitro and in vivo, the acute toxicity of nano-TiO 2 and the underlying mechanisms remain a major concern in the assessment of nanotoxicity.…”

Combination of bioanalytical approaches and quantitative proteomics for the elucidation of the toxicity mechanisms associated to TiO2 nanoparticles exposure in human keratinocytes

“…In particular, the use of TiO2-NPs in sunscreens and cosmetics makes relevant the study of their potential toxicity and hazardous effects in human skin, since they are in close contact for long periods of time. Previous reports, have evaluated the cytotoxicity (Wright et al 2017), genotoxicity (Jaeger et al 2012) or metabolic effects (Tucci et al 2013;Ren et al 2018) of TiO2-NPs in human keratinocytes. However, a further evaluation to gain a deeper insight into the biomolecular mechanisms related to those observed effects have not yet been accomplished.…”