Combination Strategy for Chronic Pain Following SCI

Chronic pain is a major issue for many people living with spinal cord injury (SCI). This pain, often uncontrollable, can be debilitating, greatly reducing overall quality of life. Neuropathic pain is difficult to manage, and up to two thirds of people with chronic SCI do not have an effective treatment option. Clinically, rehabilitation is recommended following SCI to enhance recovery, prevent secondary health complications, and maximize independence. While some favorable effects of exercise on neuropathic pain following SCI have been observed in small clinical studies, results have been modest and inconsistent.  The Miami Project is researching using combination strategies for chronic pain treatment.

Previous research in the lab of Jacqueline Sagen, Ph.D., M.B.A, Professor, Department of Neurological Surgery and The Miami Project, has shown that exercise through intensive locomotor training (ILT) can reduce the development of new pain and partially reverse existing pain. Separate studies from her lab have shown that neuropathic pain can also be reduced in a preclinical model of SCI by transplanting GABAergic neural progenitor cells (NPCs) into the spinal cord. Encouraged by the positive results from these studies, Dr. Sagen and her colleagues, therefore, decided to combine the two treatment strategies, in the hopes of maximizing potential benefits.

Dr. Sagen and her team found that the combination of cell transplants and exercise resulted in significant reductions of neuropathic pain, beyond what either therapy achieved alone. They observed a reduction in detrimental inflammatory processes and restoration of disrupted inhibitory pathways in the injured spinal cord. These positive outcomes may underlie the functional benefits observed in pain-related behaviors following treatment. Results from this combination study, Mutually Beneficial Effects of Intensive Exercise and GABAergic Neural Progenitor Cell Transplants in Reducing Neuropathic Pain and Spinal Pathology in Rats with Spinal Cord Injury, were recently published in the journal of Experimental Neurology.

Dr. Sagen said, “We were pleased and somewhat surprised to find such a strong positive interaction between the two treatments. The study clearly demonstrated better overall cell transplant function in the spinal cord in conjunction with an exercise regimen.” Added Dr. Elizabeth Dugan, Ph.D., senior author on the paper, “The development of combination therapies such as these hold great potential to help improve the overall quality of life for people with SCI.”

The development of therapies that target multiple underlying pathological mechanisms following injury, such as the combination of exercise and cellular transplantation, has potential for improving the quality of life for the many people who experience uncontrollable pain following SCI. Future studies in Dr. Sagen’s lab will focus on developing and optimizing the components of this promising combination for eventual translation to clinically relevant treatments.