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Novel psychoactive substances (NPS) may have unsuspected addiction potential through possessing stimulant properties. Stimulants normally act at the dopamine transporter (DAT) and thus increase dopamine (DA) availability in the brain, including nucleus accumbens, within the reward and addiction pathway. This paper aims to assess DAT responses to dissociative diarylethylamine NPS by means of in vitro and in silico approaches. We compared diphenidine (DPH) and 2-methoxydiphenidine (methoxphenidine, 2-MXP/MXP) for their binding to rat DAT, using autoradiography assessment of [125I]RTI-121 displacement in rat striatal sections. The drugs’ effects on electrically-evoked DA efflux were measured by means of fast cyclic voltammetry in rat accumbens slices. Computational modeling, molecular dynamics and alchemical free energy simulations were used to analyse the atomistic changes within DAT in response to each of the five dissociatives: DPH, 2-MXP, 3-MXP, 4-MXP and 2-Cl-DPH, and to calculate their relative binding free energy. DPH increased DA efflux as a result of its binding to DAT, whereas MXP had no significant effect on either DAT binding or evoked DA efflux. Our computational findings corroborate the above and explain the conformational responses and atomistic processes within DAT during its interactions with the dissociative NPS. We suggest DPH can have addictive liability, unlike MXP, despite the chemical similarities of these two NPS.

than normal cells. Here, we use two different microrheology techniques allowing us to probe the mechanical properties of cells at two different scales: the scale of the whole cell using a single cell uniaxial rheometer, and the intracellular scale using a combination of micropatterning and optical tweezers. These two techniques enable us to compare and correlate the internal visco-elastic properties with the mechanics of the entire cell. We focus our study on the mechanics of astrocytes, the major glial cell type in the brain, and gliomas, brain tumors derived from astrocytes. We first discriminate astrocytes and gliomas of different grades based on their mechanical properties. We show that rat primary astrocytes are stiffer than glioma cells from both human and rat grade III and grade IV cell lines, and that mechanical differences exist between glioma cells grades. Next, since intermediate filaments (IFs) have been involved in the migration of glial cells and since the expression of IF proteins is modified in gliomas, we evaluate the contribution of IFs to the mechanics of gliomas and astrocytes. We show that the level of IF proteins correlate with the mechanical properties of the cells and that downregulation of IF proteins lowers cell rigidity. Finally, using our intracellular technique, we are able to measure the force-deflection curve and the bending rigidity of IF bundles in cellulo.