Single-Dose Toxicity of Individual and Combined Sterigmatocystin and 5-Methoxysterigmatocistin in Rat Lungs

Toxins (Basel). 2020 Nov 23;12(11):734. doi: 10.3390/toxins12110734.

Abstract

Sterigmatocystin (STC) and 5-methoxysterigmatocystin (5-M-STC) are mycotoxins produced by common damp indoor Aspergilli series Versicolores. Since both STC and 5-M-STC were found in the dust of indoor occupational and living areas, their occupants may be exposed to these mycotoxins, primarily by inhalation. Thus, STC and 5-M-STC were intratracheally instilled in male Wistar rats using doses (0.3 mg STC/kg of lung weight (l.w.); 3.6 mg 5-M-STC/kg l.w.; toxin combination 0.3 + 3.6 mg/kg l.w.) that corresponded to concentrations detected in the dust of damp indoor areas in order to explore cytotoxicity, vascular permeability, immunomodulation and genotoxicity. Single mycotoxins and their combinations insignificantly altered lactate-dehydrogenase activity, albumin, interleukin-6, tumor necrosis factor-α and chemokine macrophage inflammatory protein-1α concentrations, as measured by ELISA in bronchioalveolar lavage fluid upon 24 h of treatment. In an alkaline comet assay, both mycotoxins provoked a similar intensity of DNA damage in rat lungs, while in a neutral comet assay, only 5-M-STC evoked significant DNA damage. Hence, naturally occurring concentrations of individual STC may induce DNA damage in rat lungs, in which single DNA strand breaks prevail, while 5-M-STC was more responsible for double-strand breaks. In both versions of the comet assay treatment with STC + 5-M-STC, less DNA damage intensity occurred compared to single mycotoxin treatment, suggesting an antagonistic genotoxic action.

Keywords: 5-methoxysterigmatocystin; Aspergilli series Versicolores; genotoxicity; intratarcheal instillation; pro-inflammatory cytokines; sterigmatocystin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Albumins / metabolism
  • Animals
  • Bronchoalveolar Lavage Fluid / chemistry
  • Comet Assay
  • Cytokines / metabolism
  • DNA Damage
  • Drug Interactions
  • L-Lactate Dehydrogenase / metabolism
  • Lung / drug effects*
  • Lung / metabolism
  • Male
  • Mutagens / toxicity*
  • Rats, Wistar
  • Sterigmatocystin / analogs & derivatives*
  • Sterigmatocystin / toxicity

Substances

  • 5-methoxysterigmatocystin
  • Albumins
  • Cytokines
  • Mutagens
  • Sterigmatocystin
  • L-Lactate Dehydrogenase