title: The presence of carbon nanostructures in bakery products induces metabolic stress in human mesenchymal stem cells through CYP1A and p53 gene expression.
abstract: Ingredients commonly present in processed foods are excellent substrates for chemical reactions during modern thermal cooking or processing, which could possibly result in deteriorative carbonization changes mediated by a variety of thermal reactions. Spontaneous self-assembling complexation or polymerization of partially combusted lipids, proteins, and other food macromolecules with synthetic food additives during high temperature food processing or baking (200-250 °C) would result in the formation of carbon nanostructures (CNs). These unknown nanostructures may produce adverse physiological effects or potential health risks. The present work aimed to identify and characterize the nanostructures from the crusts of bread. Furthermore, a toxicological risk assessment of these nanostructures was conducted using human mesenchymal stem cells (hMSCs) as a model for cellular uptake and metabolic oxidative stress, with special reference to induced adipogenesis. CNs isolated from bread crusts were characterized using transmission electron microscopy. The in vitro risk assessment of the CNs was carried out in hMSCs using an MTT assay, cell morphological assessment, a reactive oxygen species assay, a mitochondrial trans-membrane potential assay, cell cycle progression assessment and gene expression analysis. Our results revealed that bread crusts contain CNs, which may form during the bread-making process. The in vitro results indicate that carbon nanostructures have moderately toxic effects in the hMSCs at a high dose (400 μg/mL). The mitochondrial trans-membrane potentials and intracellular ROS levels of the hMSCs were altered at this dose. The levels of the mRNA transcripts of metabolic stress-responsive genes such as CAT, GSR, GSTA4, CYP1A and p53 were significantly altered in response to CNs.
authors.affiliation: Nanobiotechnology and Molecular Biology Research Lab, Department of Food Science and Nutrition, College of Food and Agriculture Science, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Al-Hadi
authors.affiliation: Nanobiotechnology and Molecular Biology Research Lab, Department of Food Science and Nutrition, College of Food and Agriculture Science, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Vaiyapuri Subbarayan
authors.initials: VS
authors.lastname: Periasamy
authors.affiliation: Nanobiotechnology and Molecular Biology Research Lab, Department of Food Science and Nutrition, College of Food and Agriculture Science, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Jegan
authors.initials: J
authors.lastname: Athinarayanan
authors.affiliation: Nanobiotechnology and Molecular Biology Research Lab, Department of Food Science and Nutrition, College of Food and Agriculture Science, King Saud University, Riyadh, Saudi Arabia. Electronic address: nano.alshatwi@gmail.com.
authors.forename: Ali A
authors.initials: AA
authors.lastname: Alshatwi
mesh_terms: D050156:Adipogenesis / Q000187:drug effects*; D001939:Bread / Q000032:analysis; D002244:Carbon / Q000633:toxicity*; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D019363:Cytochrome P-450 CYP1A1 / Q000235:genetics*; D005503:Food Additives / Q000737:chemistry; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D049329:Nanostructures / Q000737:chemistry*; D013312:Stress, Physiological; D018675:Toxicity Tests; D016159:Tumor Suppressor Protein p53 / Q000235:genetics*
chemical_list: D005503:Food Additives; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D002244:Carbon; C569463:CYP1A1 protein, human; D019363:Cytochrome P-450 CYP1A1
keywords: Antioxidant gene; CNs; Food additives; Human mesenchymal stem cells; Nanoparticles; Oxidative stress