Angiogenic Potential of 3-Nitro-4-Hydroxy Benzene Arsonic Acid (Roxarsone)

Abstract

BackgroundRoxarsone (3-nitro-4-hydroxy benzene arsonic acid) is an arsenic compound widely used in the poultry industry as a feed additive to prevent coccidiosis, stimulate growth, and to improve tissue pigmentation. Little is known about the potential human health effects from roxarsone released into the environment from chicken waste or from residual compound in chicken products.ObjectiveThe growth potentiation and enhanced tissue pigmentation suggest that low levels of roxarsone exposure may have an angiogenic potential similar to that of inorganic arsenite (AsIII). The goal of this investigation was to test the hypothesis described above using cultured human aortic and lung microvascular endothelial cells in high-content imaging tube-forming assays and begin developing a molecular level understanding of the process.MethodsWe used a three-dimensional Matrigel assay for probing angiogenesis in cultured human endothelial cells, and a polymerase chain reaction (PCR) array to probe the gene changes as a function of roxarsone or AsIII treatment. In addition, we used Western blot analysis for changes in protein concentration and activation.ResultsRoxarsone was found to exhibit a higher angiogenic index than AsIII at lower concentrations. Increased endothelial nitric oxide synthase (eNOS) activity was observed for roxarsone but not for AsIII-induced angiogenesis. However, AsIII caused more rapid and pronounced phosphorylation of eNOS. Quantitative PCR array on select genes revealed that the two compounds have different and often opposite effects on angiogenic gene expression.ConclusionsThe results demonstrate that roxarsone and AsIII promote angiogenic phenotype in human endothelial cells through distinctly different signaling mechanisms.

Inhibition of Liver X Receptor/Retinoid X Receptor–Mediated Transcription Contributes to the Proatherogenic Effects of Arsenic in Macrophages In Vitro

“…16 In fact, roxarsone, an organic arsenical used extensively in the poultry industry, stimulates growth of endothelial cells at 10 nmol/L concentrations. 41 These data suggest that arsenic has an adverse effect on cardiovascular health, even at doses at which carcinogenic effects may not be seen, 1,42 suggesting that the cardiovascular system may be more sensitive to the toxic effects of arsenic. Finally, the understanding of molecular changes induced by arsenic at low doses may lead to the identification of appropriate biomarkers and potential interventions.…”

Anti-angiogenic activity of methanol extract of Phellinus linteus and its fractions

“…After 16 h of incubation, the medium was removed and rhodaminelabeled phalloidin (Thermo Scientific, Rockford, IL) was added to stain the F-actin. Images of the fluorescently labeled cells were then collected using a Thermo Scientific Cellomics Array Scan High Contents Screening Reader (Cellomics, Pittsburgh, PA) and analyzed by an automated algorithm that identified the tubes formed by the association and clustering of the endothelial cells (Basu et al, 2008).…”

Arsenic Requires Sphingosine-1-Phosphate Type 1 Receptors to Induce Angiogenic Genes and Endothelial Cell Remodeling

“…The first model was human microvascular cells (HMVEC) that produce angiogenic responses to arsenic. 11,13 Arsenic stimulates microvascular angiogenesis in several in vivo models, and low environmental concentrations of arsenic enhance tu-mor growth. 14 -17 The second model was mouse liver sinusoidal endothelial cells (LSECs).…”