Sciatica: Biomarker Demonstrates Inflammation, Not Just Compression of Nerve Roots

MedicalResearch.com Interview with:

“osteopathic treatment for sciatica” by betterhealthosteopathy is licensed under PDM 3.0Daniel Albrecht, PhD
Research Fellow in Radiology, Harvard Medical School
Research Fellow, Massachusetts General Hospital

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: A great deal of preclinical work in animal models of pain has established that activation of peripheral immune cells or, in the central nervous system (brain and spinal cord), immune cells called “glia” (microglia and astrocytes) play a key role in the establishment and/or maintenance of persistent pain. For instance, if you pharmacologically block activation of these cells in the nervous system, you are able to reduce/inhibit/prevent pain behaviors, e.g. in animals who have received a nerve injury.

This observation is very exciting, because it suggests that blocking neuroinflammation may be a viable way of treating pain. However, the evidence linking human chronic pain with neuroinflammation has so far been limited.

In this study we show, for the first time, that patients with chronic sciatica (that is, back pain that shoots down the leg) demonstrate elevations in the levels of a protein called the translocator protein (TSPO) in the spinal cord and in the nerve roots.

Because TSPO is a marker of neuroinflammation, our results suggest that sciatica is associated with neuroinflammation.

While on average patients do show elevations in the levels of the TSPO, we also saw significant variability across individuals. Importantly, patients that show stronger elevations (in the nerve roots) were those who benefit the most from receiving a local anti-inflammatory treatment (epidural spinal injection). This makes sense: patients whose nerve roots are inflamed benefit from an anti-inflammatory treatment. Those whose nerve roots aren’t inflamed, don’t receive the same benefit. In the latter case, the source of the inflammation and pain may not be the nerve roots, but may be the spinal cord, or, as we showed in a previous paper (Loggia et al., Brain 2015), the brain.  Continue reading

Lampreys Can Regenerate Severed Spinal Cord – Maybe Humans Can Too

MedicalResearch.com Interview with:
Ona Bloom PhD
“Duluth Boat Show - Sea Lamprey Booth” by USFWSmidwest is licensed under CC BY 2.0Associate Professor, Center for Autoimmune, Musculoskeletal and Hematopoietic Diseases,
The Feinstein Institute for Medical Research
Associate Professor, Department of Molecular Medicine,
Donald and Barbara Zucker School of Medicine at Hofstra/Northwell

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Scientists have known for years that an ancient species of fish called the lamprey has a remarkable ability to rebuild their spinal cord after it’s been severed. After the lamprey spinal cord is cut, they recover from paralysis to fully swimming again in about twelve weeks, without taking any medicines or other treatments. We are studying the lamprey because we want to know the recipe of molecular ingredients that supports successful recovery after spinal cord injury.

The genome of this animal was reported about 5 years ago, in a publication led by my colleagues Dr. Jeramiah Smith at the University of Kentucky and Dr. Weiming Li at Michigan State University.  It turns out that many aspects of the lamprey genome are similar to ours, particularly in the central nervous system. Therefore, we think it is a reasonable expectation that what we learn from lamprey could give us some relevant clues about what might be different about the responses in mammals and other animals that are not good at regenerating their spinal cord.

In this study, we found that the expression of many genes in the spinal cord and brain of lampreys change during their recovery from spinal cord injury. Some of the genes that get activated are similar to what happens when our peripheral nervous system is injured, which is better at regenerating than the central nervous system. We also identified that a pathway called the Wnt pathway plays an important role in the regeneration and recovery process. This is a large, complex network of genes that are important in many biological processes, from embryological development in fruit flies to cancer in humans. Continue reading