Copper toxicity of inflection point in human intestinal cell line Caco-2 dissected: influence of temporal expression patterns
- 8 February 2021
- journal article
- research article
- Published by Springer Science and Business Media LLC in In Vitro Cellular & Developmental Biology – Animal
- Vol. 57 (3), 359-371
- https://doi.org/10.1007/s11626-020-00540-8
Abstract
We previously described a non-monotonic dose response curve at low copper concentrations where 3.125 μM CuSO4 (the early inflection point) was more toxic than 25 μM CuSO4 in Caco-2 cells. We employed global proteomics to investigate this observation. The altered expression levels of a small number of proteins displaying a temporal response may provide the best indication of the underlying mechanism; more well-known copper response proteins including the metal binding metallothioneins (MT1X, MT1F, MT2A) and antioxidant response proteins including Heme oxygenase were upregulated to a similar level in both copper concentrations and so are less likely to underpin this phenomenon. The temporal response proteins include Granulins, AN1-type zinc finger protein 2A (ZFAND2A), and the heat shock proteins (HSPA6 and HSPA1B). Granulins were decreased after 4 h only in 25 μM CuSO4 but from 24 h, were decreased in both copper concentrations to a similar level. Induction of ZFAND2A and increases in HSPA6 and HSPA1B were observed at 24 h only in 25 μM CuSO4 but were present at 48 h in both copper conditions. The early expression of ZFAND2A, HSPs, and higher levels of α-crystallin B (CRYAB) correlated with lower levels of misfolded proteins in 25 μM CuSO4 compared to 3.125 μM CuSO4 at 48 h. These results suggest that 3.125 μM CuSO4 at early time points was unable to activate the plethora of stress responses invoked by the higher copper concentration, paradoxically exposing the Caco-2 cells to higher levels of misfolded proteins and greater proteotoxic stress.Keywords
Funding Information
- Enterprise Ireland (IP/2015/0375, IP/2015/0375)
This publication has 38 references indexed in Scilit:
- Human BDH2, an anti-apoptosis factor, is a novel poor prognostic factor for de novo cytogenetically normal acute myeloid leukemiaJournal of Biomedical Science, 2013
- Hormones and Endocrine-Disrupting Chemicals: Low-Dose Effects and Nonmonotonic Dose ResponsesEndocrine Reviews, 2012
- Curcumin Ameliorates Hydrogen Peroxide-Induced Epithelial Barrier Disruption by Upregulating Heme Oxygenase-1 Expression in Human Intestinal Epithelial CellsDigestive Diseases and Sciences, 2012
- Gastric transit and small intestinal transit time and motility assessed by a magnet tracking systemBMC Gastroenterology, 2011
- AIRAP, a New Human Heat Shock Gene Regulated by Heat Shock Factor 1Online Journal of Public Health Informatics, 2010
- Copper Activation of NF-κB Signaling in HepG2 CellsJournal of Molecular Biology, 2009
- Mutations in progranulin cause tau-negative frontotemporal dementia linked to chromosome 17Nature, 2006
- A Novel Role for Human Sulfiredoxin in the Reversal of GlutathionylationCancer Research, 2006
- Mcl-1: a highly regulated cell death and survival controllerJournal of Biomedical Science, 2006
- Ueber HefegiftePflügers Archiv - European Journal of Physiology, 1888