Dataset Information

Responses of macrophages to repeated exposures to different forms of amorphous silica

ABSTRACT: Synthetic amorphous silica (SAS) is a nanomaterial used in a wide variety of applications, including the use as a food additive. Two types of SAS are commonly employed as a powder additive, precipitated silica and fumed silica. Numerous studies have investigated the effects of synthetic amorphous silica on mammalian cells. However, most of them have used an exposure scheme based on a single dose of SAS. In this study, we have used instead a repeated 10-days exposure scheme, closer to the occupational exposure encountered in daily life. As a biological model we have used the murine macrophage cell line J774A.1, as macrophages are very important innate immune cells in the response to particulate materials. In order to get a better appraisal of the macrophage responses to this repeated exposure to SAS, we have used proteomics as a wide-scale approach. Furthermore, some of the biological pathways detected as modulated by the exposure to SAS by the proteomic experiments have been validated through targeted experiments. Overall, proteomics showed that precipitated SAS induced a more important macrophage response than fumed SAS at equal dose. Nevertheless, validation experiments showed that most of the responses detected by proteomics are indeed adaptive, as the cellular homeostasis appeared to be maintained at the end of the exposure. For example, the intracellular glutathione levels or the mitochondrial transmembrane potential at the end of the 10 days exposure were similar for SAS-exposed cells and for unexposed cells. Nevertheless, important functions of macrophages such as phagocytosis, TNF and interleukin-6 secretion were up-modulated after exposure, as was the expression of important membrane proteins such as the scavenger receptor or the MAC-1 receptor. These results suggest that repeated exposure to low doses of SAS slightly modulates the immune functions of macrophages, which may alter the homeostasis of the immune system.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Mus Musculus (mouse)

TISSUE(S): Cell Culture, Macrophage

SUBMITTER: Hélène Diemer

LAB HEAD: Sarah Cianferani

PROVIDER: PXD030002 | Pride | 2022-06-09

REPOSITORIES: Pride

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Repeated Exposure of Macrophages to Synthetic Amorphous Silica Induces Adaptive Proteome Changes and a Moderate Cell Activation.

Torres Anaelle A Collin-Faure Véronique V Diemer Hélène H Moriscot Christine C Fenel Daphna D Gallet Benoît B Cianférani Sarah S Sergent Jacques-Aurélien JA Rabilloud Thierry T

Nanomaterials (Basel, Switzerland) 20220422 9

Synthetic amorphous silica (SAS) is a nanomaterial used in a wide variety of applications, including the use as a food additive. Two types of SAS are commonly employed as a powder additive, precipitated silica and fumed silica. Numerous studies have investigated the effects of synthetic amorphous silica on mammalian cells. However, most of them have used an exposure scheme based on a single dose of SAS. In this study, we have used instead a repeated 10-day exposure scheme in an effort to better ...[more]

PMID: 35564134

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