Blocking Gene Decreases Further Damage in Spinal Cord Injuries

Researchers at the University of Maryland School of Medicine have found that by blocking a gene called Abcc8, that neurological damage from spinal cord injuries can be significantly reduced in mice and rats. This research may one day provide treatment to individuals who suffer spinal cord injuries so paralysis can be prevented.

All cell membranes have an electrical charge to them. This charge is especially important for neurons as they use electrical signals to process the information they receive and send. For the cell membrane to maintain its charge there has to be a balance of ions coming in and coming out. Charged ions such as sodium, potassium, chloride and calcium with charges of +1, +1, -1, and +2, respectively, move through channels that allow one specific ion in or out of the cell (i.e., potassium channel, sodium channel). So when one ion is moving out of the cell, an ion or ions of equal charge have to enter the cell to keep the charge of the cell membrane the same and vice versa. An imbalance can be detrimental to the cell.

When an area of the body is badly injured, calcium rushes into cells. To prevent too much calcium from going in, the Abcc8 gene activates the Sulfonylurea receptor-1 protein (Sur1) to allow sodium to come in so too much calcium does not. Although this prevents too much calcium from coming into the cells, what happens is that too much sodium goes in and can cause cell death. So the mechanism that was initially meant to be protective can become the source of further damage.

By using a short strand of DNA called an oligodeoxynucleotide that binds to the gene and blocks it, researchers prevented the Sur1 gene from being activated. Researchers showed that neurological lesions present in animals that had Abcc8 blocked were one-third to one-fourth the size compared to animals in which the gene was not blocked, which means that blocking the Sur1 gene had a protective effect.

Activation of this Sur1 protein has been shown to be linked to this process of nerve cell death in mice, rats, and humans making this research highly relevant in understanding human spinal cord injuries.

With approximately 50% of people becoming paraplegic after a spinal cord injury and about 262,000 individuals in the United States living with a spinal cord injury as of 2009 according to the National Spinal Cord Injury Statistic Center, this research is very exciting. Although it takes a long time for drugs to be developed, tested and approved, this study offers hope that a drug that blocks Abcc8 could be developed and given to individuals right after suffering a spinal cord injury to prevent any further damage. [Yahoo! AFP]