Transcriptomics evaluation of hexavalent chromium toxicity in human dermal fibroblasts

ABSTRACT: Significant occupational and environmental exposures to hexavalent chromium, a metal with broad toxicity potential in humans, have been reported. In order to understand the mechanisms of dermal toxicity induced by hexavalent chromium, global gene expression profiling of human dermal fibroblasts exposed to a toxic concentration of potassium dichromate was performed. Microarray analysis of the gene expression profile in the fibroblasts treated with potassium dichromate identified significant differential expression of approximately 1,200 transcripts compared with the control cells. Hierarchical cluster analysis of the gene expression profile demonstrated a clear separation of the treated cells from the control group of cells. Functional categorization of the differentially expressed genes identified the enrichment of genes involved in several cellular processes, including apoptosis and oxidative stress, in the fibroblasts exposed to hexavalent chromium. Induction of apoptosis and generation of hydroxyl radicals indicative of oxidative stress in the dermal fibroblasts in response to their exposure to hexavalent chromium were independently confirmed by TUNEL assay and electron spin resonance (ESR) analysis, respectively. The potassium dichromate-induced cytotoxicity, differential gene expression, apoptosis, and oxidative stress were significantly blocked by the addition of ferrous sulfate, an agent known for its ability to reduce hexavalent chromium to the insoluble and therefore impermeable trivalent form, to the cell culture medium. Taken together, our data provide insights into the potential mechanisms underlying the dermal toxicity of hexavalent chromium and suggest a definite role for apoptosis and oxidative stress in Cr(VI)-induced cytotoxicity in human dermal fibroblasts.

ORGANISM(S): Homo sapiens

PROVIDER: GSE16349 | GEO | 2011/07/31

SECONDARY ACCESSION(S): PRJNA115303

REPOSITORIES: GEO