– Progress in Space Flight and Terrestrial Application
Taken from http://www.onyxmedical.com/html/NASA.html
Harry T. Whelan, M.D.1a,2,3, John M Houle, B.S.1a,
Noel T. Whelan1a,3, Deborah L. Donohoe, A.S., L.A.T.G.1a,
Joan Cwiklinski, M.S.N., C.P.N.P.1a, Meic H. Schmidt, M.D.1c,
Lisa Gould, M.D., PhD.1b, David Larson, M.D.1b,
Glenn A. Meyer, M.D.1a, Vita Cevenini3, Helen Stinson, B.S.3
1a Departments of Neurology, 1bPlastic Surgery and 1cNeurosurgery,
Medical College of Wisconsin, Milwaukee, WI 53226, (414) 456-4090
2Naval Special Warfare Group TWO, Norfolk, VA 23521, (757) 462-7759
3NASA-Marshall Space Flight Center, AL 35812, (256) 544-2121
Abstract.
This work is supported and managed through the NASA Marshall Space
Flight Center – SBIR Program. Studies on cells exposed to microgravity
and hypergravity indicate that human cells need gravity to stimulate
cell growth. As the gravitational force increases or decreases, the
cell function responds in a linear fashion. This poses significant
health risks for astronauts in long term space flight. LED-technology
developed for NASA plant grown experiments in space shows promise for
delivering light deep into tissues of the body to promote wound healing
and human tissue growth. This LED-technology is also biologically
optimal for photodynamic therapy of cancer.
LED-ENHANCEMENT OF CELL GROWTH
The
application of light therapy with the use of NASA LED’s will
significantly improve the medical care that is available to astronauts
on long-term space missions. NASA LED’s stimulate the basic energy
processes in the mitochondria (energy compartments) of each cell,
particularly when near-infrared light is used to activate the color
sensitive chemicals (chromophores, cytochrome systems) inside. Optimal LED wavelengths include 680, 730 and 880 nm.
The depth of near-infrared light penetration into human tissue has been
measured spectroscopically (Chance, et al 1988). Spectra taken from the
wrist flexor muscles in the forearm and muscles in the calf of the leg
demonstrate that most of the light photons at wavelengths between
630-800 nm travel 23 cm through the surface tissue and muscle between
input and exit at the photon detector. Our laboratory has improved the
healing of wounds in laboratory animals by using NASA LED light and
hyperbaric oxygen. Furthermore, DNA synthesis in fibroblasts and
muscle cells has been quintupled using NASA LED light alone, in a
single application combining 680, 730, and 880 nm each at 4 Joules per
centimeter squared.
Muscle and bone atrophy are
well documented in astronauts, and various minor injuries occurring in
space have been reported not to heal until landing on Earth. Long term
space flight, with its many inherent risks, also raises the possibility
of astronauts being injured performing their required tasks. The fact
that the normal healing process is negatively affected by microgravity
requires novel approaches to improve wound healing and tissue growth in
space. NASA LED arrays have already flown on Space Shuttle missions for
studies of plant growth. The U.S. Food and Drug Administration (FDA)
has approved human trials. The use of light therapy with LED’s is an
approach to help increase the rate of wound healing in the microgravity
environment, reducing the risk of treatable injuries becoming mission
catastrophes.
Wounds heal less effectively in space
than here on Earth. Improved wound healing may have multiple
applications which benefit civilian medical care, military situations
and long-term space flight. Laser light and hyperbaric oxygen have been
widely acclaimed to speed wound healing in ischemic, hypoxic wounds. An
excellent review of recent human experience with near-infrared light
therapy for wound healing was published by Conlan, et al in 1996.
Lasers provide low energy stimulation of tissues which results in
increased cellular activity during wound healing (Beauvoit, 1989, 1995;
Eggert, 1993; Karu, 1989; Lubart, 1992, 1997; Salansky, 1998; Whelan,
1999; Yu, 1997). Some of these activities include increased
fibroblast proliferation, growth factor syntheses, collagen production
and angiogenesis.
Lasers, however, have some
inherent characteristics, which make their use in a clinical setting
problematic, including limitations in wavelengths and beam width. The
combined wavelengths of light optimal for wound healing cannot be
efficiently produced, and the size of wounds which may be treated by
lasers is limited. Light-emitting diodes (LED’s) offer an effective alternative to lasers.
These diodes can be made to produce multiple wavelengths, and can be
arranged in large, flat arrays allowing treatment of large wounds. Our
experiments suggest potential for using LED light therapy at 680, 730
and 880 nm simultaneously, alone and in combination with hyperbaric
oxygen therapy, both alone and in combination, to accelerate the
healing process in Space Station Missions, where prolonged exposure to
microgravity may otherwise retard healing. NASA LED’s have proven to
stimulate wound healing at near-infrared wavelengths of 680, 730 and
880 nm in laboratory animals, and have been approved by the U.S. Food
and Drug Administration (FDA) for human trials. Furthermore,
near-infrared LED light has quintupled the growth of fibroblasts and
muscle cells in tissue culture. The NASA LED arrays are light enough
and mobile enough to have already flown on the Space Shuttle numerous
times. LED arrays may prove to be useful for improving wound healing
and treating problem wounds, as well as speeding the return of
deconditioned personnel to full duty performance. Potential benefits to
NASA, military, and civilian populations include treatment of serious
burns, crush injuries, non-healing fractures, muscle and bone atrophy,
traumatic ischemic wounds, radiation tissue damage, compromised skin
grafts, and tissue regeneration.
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