Accumulation of heme oxygenase niRVV is strongly stimulated by treatment of cultured human skin fibroblasts with ultraviolet radiation, hydrogen peroxide, or the sulfhydryl reagent sodium arsenite (S. M. Keyse and R. M. Tyrrell. Proc. Nati. Acad. Sci. USA, «5:99-103, 1989). Since this will result in a transient reduction in the prooxidant state of cells, the phenomenon may represent an importa...

The mechanisms underlying cardiovascular diseases induced by chronic exposure to arsenic remain unclarified. The objectives of this study were to investigate whether increased vascular leakage is induced by inflammatory mustard oil in mice systemically exposed to various doses of arsenic and whether an increased vascular leakage response is still present in arsenic-fed mice after arsenic discon...

background: sodium arsenite (naaso2) has potent cytotoxic activity in human cancer cells. oxidative stress has been suggested as a mechanism for arsenic-induced carcinogenesis. the purpose of the present study was to evaluate the alteration of mrna levels of catalase ( cat ) and superoxide dismutase 2 ( sod2 ) in mcf-7 and jurkat cells after exposure to naaso 2 . methods: methylthiazol tetrazol...

Although epidemiologic studies have linked arsenic exposure to the development of human cancer, the mechanisms underlying the tumorigenic role of arsenic remain largely undefined. We report here that treatment of cells with sodium arsenite at the concentrations close to environmental exposure is associated with the up-regulation of Hdm2 and the accumulation of p53 in the cytoplasm. Through the ...

Background: Arsenic as an environmental toxicant is able to induced oxidative stress. The present study aimed to evaluate of vitamin C supplementation on the paraoxonase1 (PON1) arylesterase activity (responsible for hydrolysing lipid-peroxides) in rat exposed to arsenic. Methods: The study was conducted in the Faculty of Veterinary Medicine, Tabriz Islamic Azad University, Tabriz, Iran in 2...

The subchronic treatment of mature female Wistar-strain albino rats in diestrous phase with sodium arsenite at a dose of 0.4 ppm/100 g body weight/rat/day via drinking water for period of 28 days (seven estrous cycles) caused a significant reduction in the plasma levels of leutinizing hormone (LH), follicle-stimulating hormone (FSH), and estradiol along with a significant decrease in ovarian ac...

Several epidemiological studies have suggested that exposure to arsenic is strongly correlated with the development of cardiovascular diseases such as hypertension. To determine whether arsenic affects vasomotor tone in blood vessels, we investigated the effect of arsenic on vasorelaxation using isolated rat aortic rings in an organ-bath system. Treatment with arsenite inhibited acetylcholine-i...

Although epidemiological evidence shows an association between arsenic in drinking water and increased risk of skin, lung, and bladder cancers, arsenic compounds are not animal carcinogens. The lack of animal models has hindered mechanistic studies of arsenic carcinogenesis. Previously, this laboratory found that low concentrations of arsenite (the likely environmental carcinogen) which are not...

Aim: The present investigation has been conducted to evaluate the protective activity of Tephrosia purpurea extract (TPE) against arsenic induced toxicity. Materials and Methods: For this study, twenty four wistar albino rats were taken. Control group, group – I rats were given sodium arsenite @ 10 mg/kg and group – II rats were treated with TPE @ 500 mg/kg along with sodium arsenite @ 10 mg/kg...

We investigated the effects of sodium meta-arsenite (NaAsO(2)) on human cancer cells (MDA-MB-231, MCF-7 and U-87 MG), dental papilla tissue stem cells (DPSCs) and somatic cells [MRC-5 fetal fibroblasts and adult muscle cells (MCs)] by examining telomeric properties, endogenous reverse transcriptase (RT) activity and the expression of tumorigenesis-linked genes. Half maximal inhibitory concentra...