Feature: Research leads to new insights on spinal disc degeneration

By Emily Leighton, MA’13

Does your back hurt? If so, you’re not alone. Eighty per cent of people will experience back pain in their lifetime.

According to the Global Burden of Disease study, back pain is the largest cause of years lived with disability. It’s also one of the most common reasons people go to the doctor or miss work.

But for such a widespread clinical problem, there are few effective treatments.

Scientist Cheryle Séguin, PhD, is hoping to change this. 

She is studying the cell types and pathways regulating intervertebral disc development and disease to find ways to slow or prevent degeneration. “Our idea is that if we understand the biology of the intervertebral tissue, we may be able to identify therapeutic targets,” she said.

Intervertebral discs act as cushions between the vertebrae, or bones, in the spine, carrying and absorbing load and allowing for flexibility and movement. But given that role, the discs are very prone to wear and tear, as well as age-related disease.

Obesity can also play a part, something Séguin and her research team explored in a recent collaborative study.

“Obesity isn’t just more weight on the skeleton, it’s a state of chronic inflammation in the body” she explained. “We wanted to examine the association between obesity, back pain and disc degeneration.”

The study, published in Arthritis Research and Therapy earlier this year, looked at mouse models of obesity to better understand the biological changes to the knee and spine, as well as behavioural changes caused by pain. 

Mice were fed a high-fat or Western diet (high fat and high sugar) and assessed over time. The earliest change observed by the researchers was inflammation in the knee, considered an early sign of osteoarthritis. At later stages, when the mice were on the diets for longer, biological changes and inflammation occurred in the spine, indicating an onset of disc degeneration.

These results demonstrate the domino effect of obesity, with diet accelerating degeneration that is typically associated with age. “The study shows us that these high-fat and high-sugar diets do systematically affect us, and we see inflammation all the way down to the joints,” said Séguin. “Seeing this in the spine, it shows how deep the problem goes.”

With these findings, the research team can now start asking more specific questions about how and when degenerative changes occur, as well as comparing diet-induced degeneration to age-related degeneration.

The study’s first author, recent graduate Geoff Kerr, PhD’20, spearheaded this work while completing his training with Western’s Collaborative Specialization in Musculoskeletal Health Research (CMHR). The CMHR program brings MSK researchers from different disciplines across campus together, providing an integrated training environment and opportunities to apply research to real-world, clinical contexts.  

“This research project is a direct result of students working together and interacting as part of the CMHR program,” said Séguin. “It’s this type of grassroots initiative for collaboration and interdisciplinary research that really sets Western apart from other universities with MSK research strength.”