Comparative Study of the γH2AX Foci Forming in Human Lung Fibroblasts Incubated in Media Containing Tritium-Labeled Thymidine or Amino Acids

Bull Exp Biol Med. 2021 Dec;172(2):245-249. doi: 10.1007/s10517-021-05370-6. Epub 2021 Dec 2.

Abstract

We compared the formation of γH2AX foci (marker of DNA double-strand breaks) in human lung fibroblasts (MRC-5 line) during their 24-h incubation in a medium containing 3H-labeled thymidine or amino acids (glycine, alanine, and proline) with specific radioactivity from 100 to 400 MBq/liter. A linear dependence of changes in the number of γH2AX foci on the specific radioactivity of the medium was revealed. The quantitative yield of DNA double-strand breaks under the influence of 3H-thymidine was more than 2-fold higher than under the influence of 3H-labeled amino acids. Comparative analysis of the yields of DNA double-strand breaks during cell incubation with 3H-labeled amino acids showed that 3H-alanine produced more pronounced effect that 3H-proline, which is consistent with the data on the content of their non-radioactive analogs in chromatin proteins.

Keywords: 3H-amino acids; 3H-thymidine; MRC-5; tritium; γH2AX.

Publication types

  • Comparative Study

MeSH terms

  • Amino Acids / chemistry
  • Amino Acids / pharmacology
  • Cells, Cultured
  • Culture Media / chemistry
  • Culture Media / pharmacology
  • DNA Breaks, Double-Stranded* / radiation effects
  • Fibroblasts* / drug effects
  • Fibroblasts* / metabolism
  • Fibroblasts* / pathology
  • Fibroblasts* / radiation effects
  • Histones / genetics*
  • Histones / metabolism
  • Humans
  • Lung* / drug effects
  • Lung* / metabolism
  • Lung* / pathology
  • Lung* / radiation effects
  • Neoplastic Stem Cells / drug effects
  • Neoplastic Stem Cells / radiation effects
  • Thymidine / chemistry
  • Thymidine / pharmacology
  • Tritium / chemistry
  • Tritium / pharmacology*

Substances

  • Amino Acids
  • Culture Media
  • H2AX protein, human
  • Histones
  • Tritium
  • Thymidine