The Use of NASA Light-Emitting Diode Near-Infrared Technology for Biostimulation

Abstract

Studies on cells exposed to microgravity and hypergravity indicate that human cells need gravity to stimulate 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 spaceflight. The application of light therapy with the use of NASA LEDs will significantly improve the medical care that is available to astronauts on long-term space missions. NASA LEDs 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 and our laboratory has improved the healing of wounds in laboratory animals by using both 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. An LED blanket device may be used for the prevention of bone and muscle atrophy in astronauts. The depth of near-infrared light penetration into human tissue has been measured spectroscopically.

Full text

Harry T. Whelan, M.D.
NASA Technical Reports Server (NTRS)
Providing Access to NASA's Technology, Research, and Science
"The Use of NASA Light-Emitting Diode Near-Infrared (IR) Technology for Biostimulation"
Harry T. Whelan, M.D.
Medical College of Wisconsin, Milwaukee, WI
NASA-Marshall Space Flight Center, AL
INTRODUCTION:
This work is supported and managed through the NASA Marshall Space Flight Center -
SBIR Program.
Th e Use o f NASA Light-E mitting Diode Near- Infrare d Techn ology f or
Bi os timulation
Author and Affiliation: Whelan, Harry T. (Medical Coll. of Wisconsin, Milwaukee, WI United States)
Abstract: Studies on cells exposed to microgravity and hypergravity indicate that
human cells need gravity to stimulate 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 spaceflight. The
application of light therapy with the use of NASA LEDs will significantly
improve the medical care that is available to astronauts on long-term
space missions. NASA LEDs 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 and our laboratory has improved the healing
of wounds in laboratory animals by using both 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. An LED blanket device may be
used for the prevention of bone and muscle atrophy in astronauts. The
depth of near-infrared light penetration into human tissue has been
measured spectroscopically.
Publication Date: Oct 01, 2002
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Harry T. Whelan, M.D.
Document ID: 20030001599
(Acquired Jan 03, 2003)
Subject Category: LIFE SCIENCES (GENERAL)
Document Type: Conference Paper
Publication Information: Second International Conference on Near-Field Optical Analysis:
Photodynamic Therapy and Photobiology Effects; 32-39; (NASA/CP-2002-
210786); (SEE 20030001592)
Contract/Grant/Task Num: NAS8-01166; NAS8-99015
Financial Sponsor: NASA Marshall Space Flight Center; Huntsville, AL United States
Organization Source: Medical Coll. of Wisconsin; Milwaukee, WI United States
NASA Marshall Space Flight Center; Huntsville, AL United States
Description: 8p; In English
Distribution Limits: Unclassified; Publicly available; Unlimited
Rights: No Copyright
NASA Terms: LIGHT EMITTING DIODES; SENSORY STIMULATION; NASA SPACE
PROGRAMS; NEAR INFRARED RADIATION; TECHNOLOGY
UTILIZATION; LONG DURATION SPACE FLIGHT; ASTRONAUTS;
WOUND HEALING; BONES; MITOCHONDRIA; HIGH GRAVITY
ENVIRONMENTS; OXYGEN
Studies on cells exposed to microgravity and hypergravity indicate that human cells need gravity
to stimulate 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. The
application of light therapy with the use of NASA LEDs will significantly improve the medical
care that is available to astronauts on long-term space missions. NASA LEDs 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 and our laboratory has
improved the healing of wounds in laboratory animals by using both 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. An LED blanket device may be used for the prevention of bone and muscle
atrophy in astronauts. The depth of near-infrared light penetration into human tissue has been
measured spectroscopically. 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. The light is absorbed by mitochondria where it stimulates energy metabolism in
muscle and bone, as well as skin and subcutaneous tissue. 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 and the U.S. Food and Drug
Administration (FDA) has approved human trials. The use of light therapy with LEDs can help
prevent bone and muscle atrophy as well as increase the rate of wound healing in a microgravity
environment, thus reducing the risk of treatable injuries becoming mission catastrophes.
Space flight has provided a laboratory for studying wound healing problems due to
microgravity, which mimic traumatic wound healing problems here on earth. Improved wound
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Harry T. Whelan, M.D.
healing may have multiple applications that benefit civilian medical care, military situations and
long-term space flight. Enhancing the soldier's tissue responses to injury may lead to battlefield
resilience and medical independence. Counter-measures to chemical, biological and radioactive
weapons exposures, which are based on biostimulation of natural tissue regeneration mechanisms
could be more universally safe and effective than conventional drugs and surgical modalities.
Regeneration of wounded organs and limbs may also be possible if biostimulation could re-
awaken molecular events leading to re-growth of tissue.
Central nervous system regeneration would be of particular benefit. Thus far, we have
demonstrated that the best results for wound healing occur at wavelengths of 670 nm and 880 nm
using energy densities 4-8J/cm2, applied at power intensities of approximately 50mW/cm2.
However, studies to determine molecular mechanisms could lead to the optimization for current
uses, as well as open up new applications.
Despite numerous reports on the benefits of near-IR on wound healing and rehabilitation
over the last decade, the basic mechanisms of its action remain poorly understood. Britton
Chance's group has reported that about 50% of near-IR light is absorbed by mitochondrial
chromophores, such as cytochrome oxidase. However, the underlying cellular and molecular
events are still unknown (Karu 1999, Sommer et al 2001, Whelan et al 1999,2000,2001).
METHODS:
In order to better understand the effects of LEDs on cell growth and proliferation, we
have measured radiolabeled thymidine incorporation in vitro in several cell lines and animals
treated with LED light at various wavelengths and energy levels, including 670, 730, 880nm,
50mW/cm2, 4-8J/cm2. These data are important demonstrations of cell-to-cell contact inhibition,
which occurs in vitro once cell cultures approach confluence. This is analogous, in vivo, to a
healthy organism, which will regenerate healing tissue, but stop further growth when healing is
complete. It is important to note that LED treatment accelerates normal healing and tissue
regeneration without producing overgrowth or neoplastic transformation. In addition, we have
recently begun using NASA LEDs to promote healing of acute oral lesions in pediatric leukemia
patients. A 4J/cm2, 50mW/cm2 dose of 670nm light from LEDs was applied daily to the outside of
each of 15 patients at the left cheek beginning on the day of bone marrow transplantation. The
status of their oral mucosa, mouth, and throat pain were assessed three times a week by two
calibrated dental clinicians. Throat pain was consistently higher than mouth pain, and because our
light does not extend into this region, we have used this pain as our control. Although mouth and
throat pain were initially similar, mouth pain peaked at 86% of throat pain on day 5 after
transplant and subsequently fell to only 53% of reported throat pain by day seven. The greatest
difference between throat and mouth pain was reported on day seven, when, surprisingly, oral
mucosal ulceration is believed to be worst in untreated patients.
Military Special Operations are characterized by lightly equipped, highly mobile troops
entering situations requiring optimal physical conditioning at all times. Wounds are an obvious
physical risk during combat operations. Any simple and lightweight equipment that promotes
wound healing and musculoskeletal rehabilitation and conditioning has potential merit. An LED
array with 3 wavelengths combined in a single unit (670, 720, and 880 nm) was delivered to
Naval Special Warfare Group-2 (SEALS) in Norfolk, VA. Treatment was 4J/cm2, 10mW/cm2.
RESULTS & DISCUSSION:
Figure A. The difference between LED-treated (mouth) and untreated control (throat) becomes
more dramatic over time, with daily treatment using NASA LED at 670nm, 50mW/cm2, 4J/cm2.
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Harry T. Whelan, M.D.
Figure B. Cumulative results of data from 11 patients (SEALS) showing improvement in range
of motion, pain, and girth reported as % change from chronic, unimproving injured baseline after
LED treatment at 4J/cm2, 10mW/cm2
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DIFFERENCE BETWEEN MOUTH & THROAT
0
10
20
30
40
50
Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8 Day 9
Series 1
Naval Special Warfare Group II Injury Healing
Data After NASA LED Treatment
0
20
40
60
80
100
120
140
160
1
BASEL INE
ROM
PAIN
GIRTH

Harry T. Whelan, M.D.
Fig. 1. Percent of original wound area in
experimental controls and LED treated rats.
0
20
40
60
80
100
120
140
160
180
24 hr 48hr
cont r ol
670nm
728nm
880nm
Fig. 3. 3T3 Fibroblast DNA Synthesis 8J/cm2, 50mW/cm2,
individual wavelengths. 24 and 48 hour 3H
thymidine incorporation.
0
50
100
150
200
2 Days 3 Days 4 Days
% of Contr ol
Control
4J/cm2
8J/cm2
Fig. 5a. Growth phase specificity of 3T3 fibroblasts;
combined wavelengths; 50mW/cm2; 4J/cm2 vs.
8J/cm2.
0
50
100
150
200
250
2 Days 3 Days 4 Days
Contr ol
670nm
728nm
880nm
Fig. 5c. Growth phase specificity of osteoblasts;
individual wavelengths; 50mW/cm2, 8J/cm2.
0
0.2
0.4
0.6
0.8
1
1.2
Control LED
MEAN (Wound_Area cm2) MEAN (SqrtArea)
Fig. 2. Type II Diabetic Mice with excisional skin
wounds treated with 3 LED wavelengths, 50mW/cm2,
4J/cm2. The square root of wound area is used in the
dependent variable in the analysis. This trans-
formation was needed to correct for non-constant
error in the General Linear Model. SqrtArea could be
interpreted as being proportional to the radius of a
circular wound.
0
100
200
300
400
500
600
1
3 Hou rs Inc ub at i on A f t er LED
Cont rol
4J
8J
12J
Fig. 4. 3T3 Fibroblast DNA synthesis 3 hour
incubation; LED 50mW/cm2; 4, 8, 12J/cm2.
Fig. 5b. Growth phase specificity of L-6 cells
treated at 50mW/cm2; 8J/cm2.
0
20
40
60
80
100
120
140
160
180
4HR 24HR 48HR
Cont rol
670nm
728nm
880nm
Fig. 5d. Growth phase specificity of HaCAT
epithelial cells treated with individual
wavelengths at 50mW/cm2, 8J/cm2.
Group Day 1 Day 3 Day 7 Day 12 Day 17
Control 100 73.5 ± 7.9 41.4 ± 8.4 20.4 ± 3.8 12.4 ± 2.9
LED only 100 69.2 ± 5.7 33.2 ± 6.2 14.1 ± 3.7 8.1 ± 2.0
50
75
100
125
150
175
4Hr 24Hr 48Hr
Cont ro l
670nm
728nm
880nm
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Harry T. Whelan, M.D.
0
50
100
150
200
250
Control LED
% Change from Control
Fig. 6. HaCAT epithelial cell collagen
synthesis 50mW/cm2, 8J/cm2, 670nm. 24 hour 3H proline
incorporation.
VEGF Concent ration vs. Tim e
0.0000
0.0005
0.0010
0.0015
0.0020
0.0025
0 2 4 6 8 1 0 12 14
T i me (D ay )
Cont ro l
HBO Only
HBO & LED
LED Only
Fig. 8. Change in vascular endothelial growth
factor(VEGF) concentration (µg/mg protein) vs.
time (days) in rat ischemic wound model.
P er ce nt of C han ge i n W ound Si ze vs . Ti me
0. 0 %
20 . 0 %
40 . 0 %
60 . 0 %
80 . 0 %
10 0 . 0 %
12 0 . 0 %
14 0 . 0 %
0 2 4 6 8 1 0 12 14 16
T ime ( D a y s)
Cont r ol
HB O & LED
LED Only
Fig. 7. Change in wound size in rat ischemic wound
model vs. time (days).
FGF-2 Concentration vs. Tim e
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0 2 4 6 8 10 1 2 14
T i me ( Da y)
Cont rol
HBO Only
HBO & LED
LED Only
Fig. 9. Change in basic fibroblast growth factor
(FGF-2) concentration (µg/mg protein) vs. time
(days) in rat ischemic wound model.
Near infrared (IR) light has documented benefits promoting wound healing in human
and animal studies. Our preliminary results have also demonstrated two to five-fold increases in
growth-phase-specific DNA synthesis in normal fibroblasts, muscle cells, osteoblasts, and
mucosal epithelial cells in tissue cultures treated with near-IR light. Our animal models treated
with near-IR have included wound healing in diabetic mice and ischemic bipedical skin flap in
rats. Near-IR induced a thirty percent increase in the rate of wound closure in these animal
models. Dose- and time-dependent increases in vascular endothelial growth factor (VEGF) and
fibroblast growth factor (FGF-2) occurred in animals treated with near-IR. Human studies have
included the use of near-IR to prevent ulcerative mucositis resulting from high doses of
chemotherapy and radiation. Widely published reports, including those from our laboratory,
described accelerated recovery from musculoskeletal injuries, hypoxic-ischemic wounds, burns,
lacerations, radiation necrosis, and diabetic ulcers with the use of near-IR. Lasers have some
inherent characteristics, which make their use in a clinical setting problematic, including
limitations in wavelength capabilities 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 (LEDs) developed for NASA manned space
flight experiments offer an effective alternative to lasers. These diodes can be made to produce
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Harry T. Whelan, M.D.
multiple wavelengths, and can be arranged in large, flat arrays allowing treatment of large
wounds.
CONCLUSION:
We are now investigating new collaborations with the Defense Advanced Research
Projects Agency (DARPA) for military applications of LED wound healing technology in
military medicine. Several uniquely military situations and indications could be addressed,
optimizing near-IR parameters for wound healing via LEDs during extended missions under
conditions separated from medical personnel. These include burns, chemical agents, radiation,
biological agents and highly infected flesh-eating wounds (with and without extended burns)
typical for the hygienic conditions occurring in battle fields, also infectious diseases and
external wounds occurring in environments with no solar irradiation, low oxygen and high
carbon dioxide (submarines). The dramatic results with use of near-IR LED light to prevent
digestive mucosal lesions (mucositis) and pain in cancer patients, after high-dose chemotherapy
and radiation, suggest the potential for military use of near-IR light to treat U.S. troops exposed
to chemical and radioactive warfare agents in the field. These examples illustrate the many
possible military uses for this technology. These life-saving applications require especially
accelerated wound healing, rapid reduction of infections and pain modulation. Regeneration of
muscles in amphibians has also been produced by near-IR therapy. The potential for
regeneration of human tissue also deserves study.
Lasers have some inherent characteristics, which make their use in a clinical setting
problematic, including heat, limitations in wavelength capabilities and beam width. The
combined wavelengths of the light for optimal wound healing cannot be efficiently produced. The
size of wounds which may be treated is limited (due to laser production of a narrow beam of
light; a fact inconsistent with treating large areas), heat production from the laser light itself can
actually damage tissue, and the pin-point beam of laser light can damage the eye. NASA
developed LED’s offer an effective alternative to lasers. NASA's interest is dependent on chronic
care due to tissue breakdown in microgravity for space flight. Military research with these LED’s,
in contrast, will be directed to new LED-technology aimed at rapid battlefield wound repair.
These diodes can be configured to produce multiple wavelengths, can be arranged in large, flat
arrays (allowing treatment of large wounds), and produce no heat. It is also of importance to note
that LED light therapy has been deemed to be a non-significant risk (NSR) by the FDA.
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Harry T. Whelan, M.D.
REFERENCES:
•Karu T., “Primary and secondary mechanisms of action of visible to near-IR radiation on
cells.” J. Photochem. Photobiol. B. Biol. 49,1-7 (1999).
•Sommer A.P., Pinheiro A.L., Mester A.R., Franke R.P., Whelan H.T. "Biostimulatory
windows in low intensity laser activation: Lasers, scanners and NASA's light emitting diode array
system." Journal of Clinical Laser Medicine & Surgery 19, 27-33 (2001).
•Whelan H.T., Houle J.M., Donohoe D.L., Bajic D.M., Schmidt M.H., Reichert K.W.,
Weyenberg G.T., Larson D.L., Meyer G.A., Caviness J.A., “Medical Applications of Space
Light-Emitting Diode Technology-Space Station and Beyond.” Space Tech. & App. Int’l. Forum
458, 3-15 (1999).
•Whelan H.T., Houle J.M., Whelan, N. T., Donahue, D. L., Cwiklinski, J., Schmidt, M.
H., Gould, L., Larson, D. L., Meyer, G. A., Cevenini, V., and Stinson, H."The NASA Light-
Emitting Diode Medical Program- Progress in Space Flight and Terrestrial Applications.” Space
Tech. & App. Int’l. Forum 504, 37-43 (2000).
•Whelan H.T., Buchmann E.V., Whelan N.T., Turner S.G., Cevenini V., Stinson H.,
Ignatius R., Martin T., Cwiklinski J., Meyer G.A., Hodgson B., Gould L., Kane M., Chen G.,
Caviness J. "NASA light emitting diode medical applications: From deep space to deep sea."
Space Tech. & App. Int'l Forum 552, 35-45 (2001).
•Whelan HT, Smits RL, Buchmann EV, Whelan NT, Turner SG, Margolis DA, Cevenini
V, Stinson H, Ignatius R, Martin T, Cwiklinski J, Philippi AF, Graf WR, Hodgson B, Gould L,
Kane M, Chen G, Caviness J: Effect of NASA Light-Emitting Diode (LED) Irradiation on
Wound Healing. Journal of Clinical Laser Medicine and Surgery. 2001; in press.
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