Wound Healing In A Microgravity Environment

We have all heard how space technology can benefit us all here on Earth; well, this is no exception when we look at LED therapy. While the researchers in the field were fine-tuning their devices for pain relief, NASA needed a means to 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. They worked, and NASA took the next step.

Could LED’s help in healing injuries to astronauts while in space flight? One of the major dilemmas for NASA regarding long-term space flight is the well-documented effect of muscle and bone atrophy that occurs to astronauts while in space. In addition, it has been shown that injuries that occur while in space tend not to heal until the astronaut is back within the earth’s gravity. The LED’s that produced near-infrared light used in NASA’s research were shown to stimulate the basic energy processes by activating color sensitive chemicals within the cells. DNA synthesis in fibroblasts and muscle cells had been quintupled. The light absorbed by the cells stimulated the metabolism in muscle and bone as well as skin and subcutaneous tissue.

What people and animals had felt through utilizing this technology in real life, NASA was proving to be true in the laboratory. An excellent review of recent human experience with near-infrared light therapy for wound healing was published by Conlan, et al (Conlan, 1996). Lasers provide low energy stimulation of tissues which results in increased cellular activity during wound healing (Beauvoit, 1994, 1995; Eggert, 1993; Karu, 1989; Lubart, 1992, 1997; Salansky, 1998; Whelan, 1999; Yu, 1997) including increased fibroblast proliferation, growth factor synthesis, collagen production and angiogenesis.

Lasers, however, have some inherent characteristics that make their use in a clinical setting problematic, such as 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 that may be treated by lasers is limited. Light-emitting diodes (LEDs) 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.