From: Doug Skrecky (oberon@vcn.bc.ca)
Date: Tue Jan 19 1999 - 01:39:34 MST
Authors
Grossman N. Schneid N. Reuveni H. Halevy S. Lubart R.
Institution
Skin Bank and Investigative Dermatology Laboratory, Soroka Medical Center and
Faculty of Health Science, Ben-Gurion University of the Negev, Beer Sheva,
Israel. grossman:bgumail.bgu.ac.il
Title
780 nm low power
diode laser irradiation stimulates proliferation of
keratinocyte cultures: involvement of reactive oxygen species.
Source
Lasers in Surgery & Medicine. 22(4):212-8, 1998.
Abstract
BACKGROUND AND OBJECTIVE: The purpose of this study was to determine
irradiation parameters of a 780 nm low
power CW diode laser (6.5 mW) leading to
enhanced proliferation of cultured normal human keratinocytes (NHK). The
possible role of reactive oxygen species (ROS) in this response was
evaluated. STUDY DESIGN/MATERIALS AND METHODS: NHK were exposed to a single
dose of 0 to 3.6 J/cm2 (0-180 sec) of irradiation. Proliferation parameters
studied were: incorporation of 3H-thymidine during 6-24 hr
following irradiation; percentage of dividing cells and
number of cells, 24 hr and 48 hr following irradiation,
respectively. RESULTS: Proliferation of NHK exposed to 0.45-0.95 J/cm2 was
significantly enhanced by 1.3-1.9-folds relative to sham-irradiated controls,
as inferred from parameters studied. Exposure to other energy densities was
considerably less effective in enhancing proliferation parameters. Added
enzymatic antioxidants, superoxide dismutase or catalase, scavenging
superoxide anions and H2O2, suppressed this enhanced proliferation. Added
scavengers (alpha-tocopherol acetate, scavenging lipid peroxidation, or
sodium azide, histidine, mannitol, scavenging singlet oxygen, superoxide
anions, and hydroxyl radicals, respectively), or N-acetyl cysteine, the
thiol-reducing agent, suppressed the response, but to different extents.
CONCLUSIONS: The results indicate that 780 nm
low power diode laser
irradiation enhanced keratinocytes proliferation in vitro, with an apparent
involvement of ROS in this response, and comparably, might be used to promote
their proliferation in vivo to enhance wound healing.
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