Revealing the Effects of Curcumin on SH-SY5Y Neuronal Cells: A Combined Study from Cellular Viability, Morphology, and Biomechanics

In this work, the effects of curcumin on the viability, morphology, and nanomechanics of SH-SY5Y neuronal cells were investigated using a conventional cell viability test kit (CCK-8) and sophisticated AFM imaging and force measurement techniques. CCK-8 tests show that SH-SY5Y neuronal cells have a dose-response to curcumin in terms of viability that is dependent on the exposure durations. When exposed to a maximum dosage of 32 mu g/mL used in the present study for 4 h, 24 h, and 48 h, the cell viability dropped to 73.4 +/- 4.5%, 9.1 +/- 3.2%, and 2.5 +/- 1.2% of the control, correspondingly. AFM studies show that curcumin can induce the disappearance of synapses of the cells and the change of biomechanics. After exposure for 24 h at the concentration of 16 mu g/mL, the viscous deformation of the cells decreased from 2.15 +/- 0.02 to 1.58 +/- 0.03 (x10(-15) N.m), the elastic deformation increased from 1.26 +/- 0.04 to 1.72 +/- 0.07 (x10(-15) N.m), and adhesion work decreased from 0.56 +/- 0.07 to 0.39 +/- 0.04 (x10(-16) N.m). The morphological and mechanical changes obtained using AFM can be interpreted from optically observed cellular structural changes. The present study provides insights into the effects of curcumin on neuronal cells from both biological and biophysical aspects, which can help more comprehensively understand the interactions between curcumin and SH-SY5Y cells. The demonstrated techniques can be potentially used to assess the efficacy of bioactive constituents on cells or help screen drugs.