Discrimination of multiple sclerosis patients from healthy individuals using a combination of walking ability and blood metallic nanoparticle concentrations

Abstract

BACKGROUND: The concentrations of metallic nanoparticles have been associated with symptoms of multiple sclerosis (MS), which may affect the neuronal excitatory-inhibitory balance by depositing on the myelin sheath. A balanced regulation of the cortical-striatal-thalamic-cortical pathway is necessary for optimal walking performance. Alterations in neuronal excitatory-inhibitory balance have the potential to adversely impact walking ability. AIM: To explore the importance of metallic nanoparticles to walking ability in people with MS (PwMS) and healthy controls (HC). METHODS: The present study involved 30 individuals, including 19 PwMS (EDSS=2.4 +/- 0.3) and 11 HCs. Whole blood samples were collected for the quantification of aluminum, chromium, copper, iron, magnesium, nickel, zinc and total metallic nanoparticles (T-NPs). The participant's walking ability was assessed using the Time Up and Go (TUG) test and the Six-Minute Walk Test (6MWT). RESULTS: The findings showed negative correlations between 6MWT performance and aluminum (r=-0.45,p<0.05) and copper (r=-0.44,p<0.05), and positive correlations with iron (r=0.60,p<0.007) and T-NPs (r=0.53,p<0.02). The correlations were significantly different from the control group using iron, magnesium, and T-NPs concentrations (Z>2.01;p<0.04). TUG performance correlated negatively with iron (r=-0.56,p<0.01) and T-NPs (r=-0.53,p<0.02), with significant differences from the control group using iron and magnesium (Z>2.11,p<0.04). The incorporation of T-NPs concentrations and TUG in the discriminant model yielded perfect classification in-sample, while the integration of 6MWT in the model attained 86.7% to discriminate between PwMS and HCs. INTERPRETATION: The present study demonstrated that the combination of blood metallic nanoparticle concentrations and walking ability can effectively differentiate between PwMS and HCs, and may be suggested as potential biomarkers for MS.