Chronic arsenite and ultraviolet (UV) exposure are associated with skin tumor. To investigate the details by low concentrations of arsenite and UV induced carcinogenesis in skin, hTERT-immortalized human keratinocytes were used as a cellular model with exposure to low concentrations of sodium arsenite and UV. The effect of NaAsO2 on UV treatment-induced apoptosis was measured by flow cytometry ...

Arsenic is atherogenic, carcinogenic, and genotoxic. Because atherosclerotic plaque has been considered a benign smooth muscle cell tumor, we have studied the effects of arsenite on DNA integrity of human vascular smooth muscle cells. By using single-cell alkaline electrophoresis, apparent DNA strand breaks were detected in a 4-hour treatment with arsenite at a concentration above 1 micromol/L....

Both V79 and As/R28A cells (an arsenite-resistant Chinese hamster V79 cell variant) show increased resistance to toxic concentrations of arsenite after pretreatment with a nontoxic concentration. The induced tolerance can be completely inhibited by actinomycin D or cycloheximide. Pretreatment with a nontoxic heat shock (45 degrees C, 10 min) resulted in a clear increased thermotolerance in both...

We evaluated the effects of aqueous and ethanolic leaf extracts of Ocimum basilicum (sweet basil) on sodium arsenite-induced hepatotoxicity in Wistar rats. We observed that treatment of the animals with the extracts before or just after sodium arsenite administration significantly (p < 0.05) reduced mean liver and serum γ-Glutamyl transferase (γGT), and serum alkaline phosphatase (ALP) activiti...

The protein thiol-modifying agent arsenite, a potent activator of stress signaling, was used to examine the involvement of MAPKs in the regulation of cardiac substrate uptake. Arsenite strongly induced p38 MAPK phosphorylation in isolated rat cardiac myocytes but also moderately enhanced phosphorylation of p42/44 ERK and p70 S6K. At the level of cardiomyocytic substrate use, arsenite enhanced g...

Arsenite is a well-known human carcinogen that especially targets skin. The tumor progression locus 2 (Tpl2) gene encodes a serine/threonine protein kinase that is overexpressed in various cancer cells. However, the relevance of Tpl2 in arsenite-induced carcinogenesis and the underlying mechanisms remain to be explored. We show that arsenite increased Tpl2 kinase activity and its phosphorylatio...

BACKGROUND Sodium arsenite can impair male reproductive function by inducing oxidative stress. Silymarin is known as a potent antioxidant. OBJECTIVE This study was performed to investigate if silymarin can prevent the adverse effect of sodium arsenite on ram sperm viability, motility and mitochondrial membrane potential. MATERIALS AND METHODS Epidydimal spermatozoa obtained from ram were di...

Arsenic is a known human carcinogen. These studies were designed to examine the impact of low arsenite concentrations on immediate early gene expression in precision-cut rat lung slices. Precision-cut lung slices are a versatile in-vitro system for toxicity studies, as they preserve the architecture and cellular heterogeneity of the lung. Since 0.1-100 microM arsenite did not compromise slice v...

Chronic exposure to arsenic is well known as the cause of cardiovascular diseases such as hypertension. To investigate the effect of arsenic on blood vessels, we examined whether arsenic affected the contraction of aortic rings in an isolated organ bath system. Treatment with arsenite, a trivalent inorganic species, increased vasoconstriction induced by phenylephrine or serotonin in a concentra...

Chronic arsenic toxicity is a global health problem that affects more than 100 million people worldwide. Long-term health effects of inorganic sodium arsenite in drinking water may result in skin, lung and liver cancers and in severe neurological abnormalities. We investigated in the present study whether sodium arsenite affects signaling pathways that control cell survival, proliferation and n...