Blue light differentially alters cellular redox properties

Jill B. Lewis, John C. Wataha, Regina L.W. Messer, Gretchen B. Caughman, Tetsuya Yamamoto, Stephen D. Hsu

Research output: Contribution to journalArticlepeer-review

53 Scopus citations


Blue light (λ = 380-500 nm) historically has been used to initiate polymerization of biomaterials and recently has been proposed as a therapeutic agent. New evidence suggests that cell-type-specific responses result from redox changes induced by exposure to blue light. Cultured cells were exposed to defined doses of blue light, equivalent to exposure times of 10 s and 2 min, to achieve energies of 5 J/cm2 and 60 J/cm2, respectively, after which (a) viable cell number, (b) cellular protein profiles, (c) mitochondrial succinate dehydrogenase (SDH) activity, (d) total reactive oxygen species (ROS), and (e) induction of apoptosis were compared to that of nonexposed control cultures. Results showed that blue-light exposure arrested monocyte cell growth and increased levels of peroxiredoxins. SDH activity of normal epidermal keratinocytes (NHEK) was slightly enhanced by blue light, whereas identical treatment of OSC2 oral tumor cells resulted in significant suppression of SDH activity. Blue-light exposure generally induced higher levels of total ROS in OSC2 cells than in NHEK. Finally, only OSC2 cells exhibited signs of apoptosis via Annexin V staining following exposure to blue light. These data support the central hypothesis that blue light induces an oxidative stress response in cultured cells resulting in cell-type-specific survival outcomes. The identification of oxidative stress as a mediator of the effects of blue light is a critical first step in defining its biological risks and therapeutic opportunities.

Original languageEnglish (US)
Pages (from-to)223-229
Number of pages7
JournalJournal of Biomedical Materials Research - Part B Applied Biomaterials
Issue number2
StatePublished - Feb 15 2005


  • Apoptosis
  • Oral tumor cells
  • Oxidative stress
  • Proteomics
  • Visible light

ASJC Scopus subject areas

  • Biomaterials
  • Biomedical Engineering


Dive into the research topics of 'Blue light differentially alters cellular redox properties'. Together they form a unique fingerprint.

Cite this