Trivalent arsenicals induce skin toxicity through thiol depletion

Toxicol Appl Pharmacol. 2024 Nov:492:117115. doi: 10.1016/j.taap.2024.117115. Epub 2024 Sep 30.

Abstract

Arsenic, a widespread environmental contaminant, is highly toxic to human health. Arsenic exposure is associated with the occurrence of skin lesions and diseases. This study investigated the dermal toxicity of trivalent arsenicals (AsIII and MMAIII) and its underlying mechanism using human keratinocyte cell line and ex vivo porcine skin. AsIII and MMAIII induced concentration-dependent cell apoptosis and necrosis in HaCaT cells, which was confirmed in ex vivo porcine skin. AsIII and MMAIII increased reactive oxygen species generation and GSH depletion. Interestingly, radical scavenger antioxidants such as Vitamin C failed to mitigate arsenic-induced cytotoxicity, while thiol-containing compounds effectively alleviated it, suggesting a key role of thiol depletion in the trivalent arsenical-induced dermal toxicity. DMSA showed the strongest protective effects against AsIII and MMAIII-induced cytotoxicity in HaCaT cells. Of note, DMSA restored arsenical-induced tissue damage, and reduced the apoptosis in ex vivo porcine skin, highlighting its potential use to alleviate arsenic-induced skin lesions and diseases.

Keywords: Arsenic; Cytotoxicity; Ex vivo porcine skin; Keratinocyte; Monomethylarsonous acid; Thiol.

MeSH terms

  • Animals
  • Antioxidants / pharmacology
  • Apoptosis* / drug effects
  • Arsenicals*
  • Arsenites / toxicity
  • Cacodylic Acid / analogs & derivatives
  • Cell Line
  • Glutathione / metabolism
  • HaCaT Cells
  • Humans
  • Keratinocytes* / drug effects
  • Keratinocytes* / metabolism
  • Oxidative Stress / drug effects
  • Reactive Oxygen Species / metabolism
  • Skin* / drug effects
  • Skin* / metabolism
  • Skin* / pathology
  • Sulfhydryl Compounds* / metabolism
  • Swine

Substances

  • Sulfhydryl Compounds
  • Arsenicals
  • Reactive Oxygen Species
  • Glutathione
  • Arsenites
  • dimethylarsinous acid
  • Antioxidants
  • Cacodylic Acid