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Optimizing the energy status of skin cells during solar radiation

E L Jacobson1, P U Giacomoni, M J Roberts

  • 1College of Pharmacy and Arizona Cancer Center, University of Arizona, 1515 N. Campbell Avenue, Tucson, AZ 85724, USA. elaine.jacobson@pharmacy.arizona.edu

Journal of Photochemistry and Photobiology. B, Biology
|October 31, 2001
PubMed

Insights

Radiation exposure damages cells by altering DNA and proteins, leading to energy depletion. Poly(ADP)-ribose polymerase (PARP-1) plays a key role in this process, impacting cellular fate after DNA damage.

Area of Science:

  • Cellular biology
  • Molecular biology
  • Radiation biology

Background:

  • Ionizing and ultraviolet radiation induce cell damage via DNA/protein alterations and reactive species.
  • These processes disrupt cellular energy metabolism, impacting ATP levels.
  • DNA strand breaks activate pathways consuming NAD, crucial for cellular energy.

Purpose of the Study:

  • To investigate the role of Poly(ADP)-ribose polymerase-1 (PARP-1) in cellular responses to UV-B radiation.
  • To understand how PARP-1 activation affects NAD levels and cellular energy status.
  • To explore PARP-1's function in DNA damage surveillance and protein degradation.

Main Methods:

  • In vivo studies on mouse epidermis.
  • In vitro studies on human cells.
  • Analysis of NAD degradation and ADP-ribose polymer synthesis.

Main Results:

  • UV-B radiation causes transient NAD degradation and PARP-1-mediated ADP-ribose polymer synthesis.
  • PARP-1 activation is linked to nuclear proteasome activation and degradation of damaged proteins.
  • The enzyme acts as a surveillance component in eukaryotic cells following genotoxic stress.

Conclusions:

  • PARP-1 is a critical enzyme in cellular response to UV-B radiation-induced DNA damage.
  • Understanding PARP-1's role is vital for developing strategies to mitigate solar radiation effects on skin.
  • Optimizing cellular energy status during DNA repair is essential for cell survival.

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