Reperfusion injury takes place when an animal or an organ is starved of oxygen,
then exposed to oxygen again.
This occurs in strokes and organ transplants and causes many deaths per year.
Now scientists at UNLV, Sable Systems International and UCSD have discovered
that reperfusion injury can be induced in fruit-flies, a convenient, cheap,
well-characterized model animal. The research paper describing their results
will be published in PLoS ONE.
"With this new model, researchers can explore the mechanisms of reperfusion
injury with a classic animal model that's much cheaper and easier to use than
vertebrates such as mammals", said Dr. John Lighton, an adjunct professor at
UNLV, president of Sable Systems International (a Nevada based company that
manufactures precision respirometry systems) and lead scientist. Dr. Pablo
Schilman, a physiologist at UCSD, co-authored the research. "Use of this method
creates a window into the cells' mitochondria. Using Drosophila as a model may
mean faster progress in mitigating the human toll of reperfusion injury, which
we still don't fully understand. And what we don't fully understand, we can't
treat effectively."
The study, which was funded by Sable Systems International's Basic Research
Initiative and took place in Sable Systems' respirometry laboratory in Las
Vegas, started out with the first detailed metabolic examination of the
fruit-fly's ability to survive a complete lack of oxygen for an hour or more.
"By accident," explains Dr. Lighton, "we discovered that exposing fruit-flies to
one or more brief bursts of oxygen while they were otherwise oxygen-starved,
injured their respiratory systems irreversibly - classic reperfusion injury."
Dr. Lighton and Dr. Schilman tracked damage to the flies' respiratory systems by
measuring the water vapor and carbon dioxide lost by individual flies weighing
less than a thousandth of a gram. The carbon dioxide output provided an index of
mitochondrial activity, while respiratory water loss tracked the functional
state of the fly's neuromuscular system. When asked how such tiny signals were
measured, Dr. Lighton said "Carefully. For more details, see the paper. But in
any event, we now have ways of measuring reperfusion injury in Drosophila. So,
it's possible both to improve our understanding of the process and to test
strategies for mitigating it - using," continued Dr. Lighton, "an animal most
people don't have an emotional reaction to, other than a desire to swat it. We
hope that biomedical researchers will pick up on this opportunity."
