Rats paralyzed due to loss of blood flow to the spine returned to near normal ambulatory function six weeks after receiving grafts of human spinal stem cells (hSSCs), researchers from the University of California, San Diego (UCSD) School of Medicine report. The study, led by Martin Marsala, M.D., UC San Diego professor of anesthesiology, is published in the June 29, 2007 issue of the journal Neuroscience, which is now online.
“We demonstrated that when damage has occurred due to a loss of blood flow to the spine’s neural cells, by grafting human neural stem cells directly into the spinal cord we can achieve a progressive recovery of motor function,” said Marsala. “This could some day prove to be an effective treatment for patients suffering from the same kind of ischemia-induced paralysis.” Marsala is currently testing the human stem cell therapy for safety and efficacy in other animal models, and hopes to move to clinical trials in humans by next year.
Paraplegia from spinal cord ischemia is a serious complication that occurs in 20 to 40 percent of patients undergoing a surgical process called aortic cross-clamping. When the surgeon works on the aorta, a major blood vessel, to correct a potentially lethal aneurysm, blood flow from the heart must be temporarily blocked with a clamp. After 30 minutes, this lack of blood flow can result in the death of specialized spinal cord neurons called spinal inhibitory neurons, leading to irreversible spasticity and rigidity, or loss of muscle control, in the lower limbs, even though the spinal cord is intact.
“The important difference between spinal cord ischemia and spinal cord trauma, such as might occur in a diving or car accident, is that in the ischemia model, no mechanical damage has occurred to the spinal cord,” said Marsala. “The spinal cord and brain motor centers are still partially connected, but there has been a selective loss of inhibitory neurons in the spinal cord. Since th
Source:University of California - San Diego