Ascorbic acid maintenance in HaCaT cells prevents radical formation and apoptosis by UV-B

Isabella Savini, Ida D'Angelo, Marco Ranalli, Gerry Melino, Luciana Avigliano

Research output: Contribution to journalArticle

Abstract

We have investigated the enzymatic reduction and accumulation of vitamin C in HaCaT epithelial cells. The subcellular localization and the activities of ascorbyl free radical reductase and dehydroascorbate reductase showed that mitochondrial, microsomal and plasma membranes fractions express high levels of ascorbyl free radical reductase activity, whereas dehydroascorbate reductase activity was found at low levels only in the post microsomal supernatant. We have also investigated cell proliferation and vitamin C accumulation induced by ascorbic acid 2-phosphate. This derivative caused no inhibition of cell growth, was uptaken from the extracellular medium and accumulated as ascorbic acid in mM concentrations. These results show that HaCaT cells possess very efficient systems to maintain high levels of both intracellular and extracellular ascorbic acid. The regeneration and uptake of ascorbic acid from extracellular medium contributes to the intracellular antioxidant capacity, as evaluated by 2',7'-dihydrodichlorofluorescein staining. Consequently, cells became more resistant to free radical generation and cell death induced by UV-B irradiation.

Original languageEnglish
Pages (from-to)1172-1180
Number of pages9
JournalFree Radical Biology and Medicine
Volume26
Issue number9-10
DOIs
Publication statusPublished - May 1999

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Keywords

  • Apoptosis
  • Ascorbic acid 2-phosphate
  • Ascorbyl free radical reductase
  • Dehydroascorbate reductase
  • Free radicals
  • HaCaT cells
  • Keratinocytes

ASJC Scopus subject areas

  • Medicine(all)
  • Toxicology
  • Clinical Biochemistry

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