April 3, 2017Neurology
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease in which motor neurons, cells that control muscle activity such as walking, talking and breathing, gradually die off, resulting in paralysis. There is no cure for ALS.
A study in Neurology (22 February 2017) suggests that analyzing levels of the protein p75ECD in urine samples from people with ALS) may help monitor disease progression as well as determine the effectiveness of therapies. The authors discovered that levels of urinary p75 ECD increased gradually in patients with ALS as their disease progressed over a 2-year study period. The study was supported by National Institute of Neurological Disorders and Stroke (NINDS) and National Center for Advancing Translational Sciences (NCATS), both part of the National Institutes of Health.
Analysis of the samples from 54 patients revealed that those who began the study with lower levels of urinary p75ECD survived longer than did patients who had higher levels of the protein initially, suggesting that it could be a prognostic marker of the disease and may inform patients about their illness. The authors noted that this may be useful in selecting participants for clinical trials and in improving study design. The protein p75 is important early in life, but does not appear in adults unless motor neurons are injured. Previous studies in mouse models of ALS reported that p75 was re-expressed in motor neurons as the animals became sick and p75ECD was found in the urine of the mice even before they exhibited muscle weakness. p75 has also been seen on motor neurons in post-mortem tissue from ALS patients.
According to the authors, more research is needed to validate the use of urinary p75ECD as a biomarker of ALS and to further investigate the role of the protein in the disease.