Importance of the Serum Biochemical Parameters As Potential Biomarkers for Rapid Diagnosis and Evaluating Preclinical Stage of ALS

Amyotrophic lateral sclerosis (ALS) is a fatal neurological disorder affected by both genetic and environmental factors. Since ALS is a heterogenic disease, symptoms vary among patients and there are no prognostic biomarkers, 18 months of delay occur from the onset of symptoms to confirmation of the diagnosis. Additionally, there are only two FDA-approved drugs, riluzole and edaravone, which are more effective at the early stages of ALS. Therefore, establishing biomarkers for ALS patients are vital for rapid and accurate diagnosis. Several biomarkers including genetic, biochemical, neurophysiological, cerebrospinal fluid (CSF) and imaging data have been reported for the diagnosis and evaluating progression of ALS, however none of them have been studied in the preclinical stage of ALS and superiority of different biomarkers have not been evaluated until now. We hypothesized that serum biochemical parameters can be used as potential biomarkers for diagnosis and evaluation of ALS progression even at the preclinical stages. Because, serum biochemical parameters are widely used, easy to measure, routine and cheaper approach to measure certain serum biochemistry parameters helping diagnosis and progression of several diseases. Moreover ALS causes hypermetabolic state which leads to malnutrion, losing weight and muscle mass in patients. Thus protein, lipid and carbohydrate metabolisms are impaired in the ALS patients. These impairments can be observed via serum biochemical parameters indicating nutrient metabolism and muscle destruction. Additionally, pathological changes in ALS have been started before disease symptoms manifesting. Therefore we hypothesized serum biochemical parameters can be used to prognosis and evaluate preclinical stages of ALS.