Back pain, a hallmark of degenerative disc disease, sends millions of people to their doctor. In fact, more than 80 percent of patients who undergo spine surgery do so because of disc degeneration.
And part of the answer may be as close as a patient's medicine cabinet.
In their quest to discover ways to stop or reverse degenerative disc disease, orthopaedic researchers have been removing disc tissue from patients who are having spine surgery and extracting cells from that tissue for cultivation in vitro (a controlled environment outside of a living organism). They then transfer the cells back into the patient. Shu-Hua Yang, MD, PhD, is part of a Taiwanese research team that has discovered that Lovastatin, a cholesterol-lowering medication, helps the differentiation of disc cells in vitro.
Dr. Yang, who is chief of the department of orthopedics at National Taiwan University Hospital, Yun-Lin-Branch, is presenting the group's findings in the poster "Lovastatin Helps Re-Differentiation of Human Nucleus Pulposus Cells During Monolayer Expansion" during the 55th Annual Meeting of the Orthopaedic Research Society, Feb. 22-25, 2009, in Las Vegas. Dr. Yang is also presenting the results of a related study, "Influences of Age-Related Degeneration on Regenerative Potential of Human Nucleus Pulposus Cells," at the same meeting. The two studies reveal the findings of a team of researchers from National Taiwan University Hospital.
In one study, the researchers removed nucleus pulposus tissues from six human patients. (Nucleus pulposus is the jelly-like substance in the middle of the spinal disc.) The patients, ages 23 to 29, were undergoing surgery for herniated lumbar discs. Researchers then isolated the nucleus pulposus cells and eventually added Lovastatin, hoping to optimize the properties of the regenerative tissues. They hoped to maximize the expression of collagen II and minimize the expression of collagen I, two proteins involved in facilitating bone formation.
They reported the following results:
• After 72 hours, researchers found that the number of nucleus pulposus cells had increased.
• Lovastatin increased the synthesis of collagen II, a protein that makes up moveable joints, and decreased the synthesis of collagen I, a protein that is related to fibrosis (the formation or development of excess fibrous connective tissue).
• Lovastatin had no cytotoxicity (the quality of being toxic) on nucleus pulposus cells.
"Regeneration of the nucleus pulposus tissue in the early stage of intervertebral disc degeneration can theoretically retard or even reverse the degenerative process and possibly regain a healthy intervertebral disc," says Dr. Yang. "Further studies are needed to determine the potentials of statins for regeneration and repair of degenerative disc disorders."