ADVERTISEMENTS
Learn about diversity at ASEE
ASEE would like to acknowledge the generous support of our premier corporate partners.

UP CLOSE - Innovators at work and in the classroom

Foreground: Grégoire Courtine - Images courtesy of EPFL

Shock and Awe

Electrical stimuli, robotics, and drugs get paralyzed rats up and running. Humans could be next.


By Thomas K. Grose


Can damaged spinal columns be reengineered so that some paraplegics regain their ability to walk? That possibility may be a step closer to reality. A team of researchers in Switzerland led by Grégoire Courtine, an associate professor of life sciences at École Polytechnique Fédérale de Lausanne’s Brain Mind Institute, has gotten paralyzed rats walking again by using a combination of tissue growth-enhancing drugs, electrical stimuli, and rigorous training. They’re now planning trials to see if the technology will also work with humans.

The researchers first injected the rats with what Courtine calls “a cocktail of pharmaceutical agents.” They then applied an electrical stimulus at two points along the rats’ spinal column, just below the wound. The rats were rigged into a vest and harness linked to a robotic apparatus that safely supported them but did not facilitate walking. To give the rats an incentive to move, a small chunk of chocolate was dangled just ahead of them. Next came a lot of tough training for the rats, 30 minutes a day. But within two to three weeks, the rats begin to take a few shaky steps on their own. After six weeks, all were walking independently, and some were even sprinting and negotiating stairs.

The drugs mimic neurotransmitters in the brainstem and encourage the brain to sprout neurons, which entices the central nervous system to find new routes around the severed part of the cord and reconnect itself. “I use the analogy of a car,” Courtine says, with the brain acting like an engine, the spinal column like a drivetrain, and the spark like an accelerator. “Without the stimulus, there is no locomotion.” The one caveat is that the treatment works only in those instances where the spinal cord is partly, but not wholly, severed. However, that is the case for roughly a quarter to a third of human paraplegics.

“It is completely an engineering operation,” Courtine says of his experiments. “Half of my lab is engineers,” including roboticists and electrical engineers. The procedure requires constant stimulation, and Courtine is working with Finetech Medical, a British engineering company, and Nick Donaldson, a professor of bioengineering at University College London, to design and develop an implant for use in humans. The team will initially use just stimulation and the robotic apparatus with human subjects, adding the drugs only very slowly afterward because of possible side effects. Human trials should start within three years.

Courtine is building upon work begun by V. Reggie Edgerton, a professor of integrative biology at the University of California, Los Angeles (UCLA). Edgerton’s team, using similar tactics, has enabled Rob Summers, a 23-year-old paraplegic, to stand for a few minutes at a time and take a few assisted steps on a treadmill. French-born Courtine initially studied mathematics and physics but earned his Ph.D. in experimental medicine from the University of Pavia, Italy, and was a postdoc at UCLA. He calls Edgerton “a pioneer” of the field and refers to him as “my mentor.”

Though Courtine admits to spending seven days a week in his lab, the 37-year-old also finds time to play the piano — Chopin, mostly — and sports, particularly tennis and snowboarding.

Asked if the hardworking rats are ever rewarded with the chunks of chocolate, Courtine chuckles, and explains that the sweet treats are necessary only in the early stages of the regimen. Once the rats get the hang of walking, that’s motivation enough. “They love to walk. They love to go and go and go and go.” And the dream that this technology could one day help some paraplegics to walk again is motivation enough for the energetic Courtine.

 

Thomas K. Grose is Prism’s chief correspondent, based in London.

Images courtesy of EPFL

 


ASEE
© Copyright 2012
American Society for Engineering Education
1818 N Street, N.W., Suite 600
Washington, DC 20036-2479
Web: www.asee.org
Telephone: (202) 331-3500