Akademik Veri Yönetim Sistemi
World Immune Regulation Meeting XVII 2023, Zürich, İsviçre, 5 - 08 Temmuz 2023, cilt.17, sa.48, ss.48
The barrier function of the epithelia is crucial for maintaining homeostasis in the human body. Environmental exposures, such as food additives introduced to our lives with modernization and industrialization may alter the epithelial barrier integrity and influence the development of diseases. In the present study, a microfluidic-titer plate was used to enable the formation of a tubular barrier by Caco-2 cells to examine the effects of commonly used food additives on the gut epithelial barrier. Several commonly used food additives, such as sunflower derived lecithin (SunLec), diacetyl tartaric acid esters of mono- and diglycerides (DATEM), sodium saccharin (NaSa), and carboxymethylcellulose (CMC) were examined at consumer-relevant doses using transepithelial electrical resistance (TER) measurement, FITC-dextran permeability assay, immunofluorescence staining of tight junction proteins, and targeted proteomics using proximity extension assay. Results showed that DATEM, SunLec and NaSa exhibited a dose-dependent cytotoxicity in Caco-2 monolayers with cytotoxicity exceeding 40% when exposed to 0.25 mg/ml of DATEM, 0.39 mg/ml of SunLec and over 20% when exposed to NaSa above 1.56 mg/ml. However, CMC did not have any cytotoxic effect for all used doses. Moreover, DATEM, SunLec and NaSa elicited a dose- and time-dependent decrease of relative TER on a gut-on-a-chip model, with a significant increase in the paracellular flux of FITC-dextran 4kDa. Immunofluorescence staining of occludin and ZO-1 on a gut-on-a chip model indicated irregular and heterogeneous protein localization after exposure to food additives. Although CMC did not exhibit any effects on cytotoxicity and barrier integrity, it did induce the production of pro-inflammatory molecules, similar to DATEM, SunLec, and NaSa, as detected by targeted proteomics using proximity extension assay. SunLec specifically upregulated cytokine-mediated signaling pathways, such as the nucleotide-binding oligomerization domain (NOD)-like receptor and mitogen-activated protein (MAP) kinase pathways. DATEM, on the other hand, upregulated the NF-kB, NOD-like receptor signaling and MAP kinase pathway. Conversely, CMC resulted in the upregulation of proinflammatory and profibrotic mediators. Additionally, NaSa upregulated chemokines associated with granulocyte chemotaxis, response to IL-1β, and MAP kinase pathways. In conclusion, current data shows that the commonly used food additives have a deleterious effect on gut barrier integrity in vitro.