Nicotine's Effect on the Disc

Nicotine is the major chemical in tobacco. Scientists have found that nicotine speeds up disc degeneration in the spine. They want to know how this happens. Perhaps knowing how nicotine acts on the disc will help researchers find ways to stop it.

We already know how nicotine increases blood pressure by closing down blood vessels and making it harder for the blood to get through. Maybe a lack of blood to the disc is what also causes the damage. Or maybe nicotine has a more direct effect on the discs. This is what the authors of this study are looking at.

The researchers took two groups of rats and harvested cells from their discs. One group had nicotine painted on the cells. The other group had no treatment. The second group was the control group used for comparison.

They found that nicotine stops type II collagen from forming in the center of the disc. This part of the disc is called the nucleus pulposus. Collagen is a protein that makes up the fibers of soft tissues like disc, tendons, ligaments, and cartilage. The nicotine stops collage formation by cutting off a signal to a special growth factor called bone morphogenetic protein-2 (BMP-2).

A major feature of disc degeneration is the loss of normal cells in the nucleus pulposus. The results of this study suggest nicotine’s effect on BMP-2 is the reason for this loss.

The authors of this study think these findings may also apply to nicotine’s effect on inhibiting bone formation. For example, when the spine is fused in surgery, patients who smoke have a much slower healing rate and higher fusion failure rate. This study is just the first of many needed to unravel the mystery of nicotine’s effect on the spine.