This transformation was discovered by Sanford Burnham Prebys Medical Discovery Institute in mouse models of amyotrophic lateral sclerosis, spinal atrophy and spinal cord injury; a discovery which may inspire new methods of treatments for those conditions and other neurological conditions.
The muscle repairing cells identified are fibro-adipogenic progenitors. While studying mice and muscle from ALS patients researchers found that the fibro-adipogenic progenitors activate IL-6-STAT3 signalling pathway which alerts the immune system to go into overdrive causing muscle wasting; when the pathway was blocked muscles stopped wasting.
Characterization of fibro-adipogenic progenitors is considered to be a key step forward in the understanding of motor neuron diseases. Researchers can use the discovery to begin working on designing medicines to target these cells or use them as markers of disease progression.
The discovery was made while tracking process involved in muscle repair including stem cells and macrophages; when it was found that when muscle sustain acute injury FAPs show up after macrophages before stem cell leaving within a week when the muscle is on way to recovery. When there is muscle denervation FAPs gather in increased numbers inside muscles and never leave, no signs of macrophages or muscle stem cells could be found in denervation models. Investigating the odd FAPs more closely it was found that elevated levels of IL-6 which is an inflammatory protein promoting muscle atrophy.
Next phase for the team is to better characterize the IL-6-STAT3 pathway to help promote development of medicines which target it. Differences discovered in these FAP cells provides opportunity to selectively remove bad disease causing cells, or convert the cells so they can repair nerves explains Pier Lorenzo Puri, M.D.
Researchers are continuing efforts to gain better understandings of the underpinnings of ALS and other brain disorders despite history of failed attempts at drug development in neurological disorders. Stanford scientists earlier have used CRISPR-Cas9 gene editing systems to discover a gene that can be blocked to shield neurons from cell death.