Promoting identification of amyotrophic lateral sclerosis based on label-free plasma spectroscopy.

ABSTRACT: OBJECTIVE:Amyotrophic lateral sclerosis (ALS) is an adult-onset fatal neurodegenerative disease which lacks identified biological markers. A label-free plasma surface-enhanced Raman spectroscopy (SERS) method was developed to explore a simple and noninvasive test for ALS. METHODS:ALS patients were enrolled serially and plasma samples were collected at the time of diagnosis prior to the start of ALS treatment. SERS spectra were recorded using a Renishaw micro-Raman system. RESULTS:To exclude the interference by varying disease severity, we enrolled three groups of ALS patients, including ALS-1 (n = 60; ALSFRS-R ? 42 and time interval ? 12 months), ALS-2 (n = 61; ALSFRS-R < 42 and time interval ? 12 months), and ALS-3 (n = 61; ALSFRS-R ? 38 and time interval> 12 months). The SERS spectra were analyzed using principal component analysis (PCA), which showed that ALS-1, ALS-2, ALS-3, and control groups were separated significantly. Then, decision tree (DT) models and receiver operating characteristic curves were employed and identified that bands at 722 and 739 cm-1 , and ratios of 635-722 cm-1 and 635-739 cm-1 were able to distinguish ALS from controls significantly. Finally, we highlighted six metabolism pathways correlated with ALS, including phenylalanine-tyrosine-tryptophan biosynthesis, aminoacyl-tRNA biosynthesis, phenylalanine metabolism, pantothenate and CoA biosynthesis, porphyrin and chlorophyll metabolism, and pyrimidine metabolism. INTERPRETATION:Plasma SERS could be a promising tool for the detection of ALS. The bands at 722 and 739 cm-1 , and the ratios of 635-722 cm-1 and 635-739 cm-1 could serve as potential indicator for ALS.

SUBMITTER: Zhang QJ 

PROVIDER: S-EPMC7545607 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature