Atomic force microscopy reveals new biomarkers for monitoring subcellular changes in oxidative injury: neuroprotective effects of quercetin at the nanoscale

Abstract

Oxidative stress is a process involved in the pathogenesis of many diseases, including atherosclerosis, hypertension, diabetes, Alzheimer's disease etc. The biomarkers for assessing the degree of oxidative stress have been attracting much interest because of their potential clinical relevance in understanding cellular effects of free radicals and evaluation of the efficacy of drug treatment. Here, an interdisciplinary approach using atomic force microscopy (AFM) and cellular and biological molecular methods were used to obtain new potential biomarkers for monitoring oxidative stress condition. Biological methods confirmed the oxidative damage of investigated P19 neurons and revealed the underlying mechanism of quercetin protective action. AFM was employed to evaluate morphological (roughness) and nanomechanical (elasticity) properties that may be specific biomarkers for oxidative stress-induced cytoskeletal reorganization manifested by changes in the lateral dimension and height of neuronal somas.The morphological and nanomechanical analysis of neurons showed the strong mutual correlation between changes in cell membrane elasticity and neuroprotective effects of quercetin. Our findings indicate that AFM is a highly valuable tool for biomedical applications, detection and clarifying of drug-induced changes at the nanoscale and emphasize the potential of AFM approach in the development of novel therapeutic strategies directed against oxidative stress-induced neurodegeneration.