Low dose DMSO treatment induces oligomerization and accelerates aggregation of α-synuclein

Abstract

Dimethyl sulfoxide (DMSO) is a highly utilized small molecule that serves many purposes in scientific research. DMSO offers unique polar, aprotic and amphiphilic features, which makes it an ideal solvent for a wide variety of both polar and nonpolar molecules. Furthermore, DMSO is often used as a cryoprotectant in cell-based research. However, recent reports suggest that DMSO, even at low concentration, might interfere with important cellular processes, and cause macromolecular changes to proteins where a shift from α-helical to β-sheet structure can be observed. To investigate how DMSO might influence current research, we assessed biochemical and cellular impacts of DMSO treatment on the structure of the aggregation-prone protein α-synuclein, which plays a central role in the etiology of Parkinson’s disease, and other brain-related disorders, collectively termed the synucleinopathies. Here, we found that addition of DMSO increased the particle-size of α-synuclein, and accelerated the formation of seeding-potent fibrils in a dose-dependent manner. These fibrils made in the presence of DMSO were indistinguishable from fibrils made in pure PBS, when assessed by proteolytic digestion, cytotoxic profile and their ability to seed cellular aggregation of α-synuclein. Moreover, as evident through binding to the MJFR-14-6-4-2 antibody, which preferentially recognizes aggregated forms of α-synuclein, and a bimolecular fluorescence complementation assay, cells exposed to DMSO experienced increased aggregation of α-synuclein. However, no observable α-synuclein abnormalities nor differences in neuronal survival were detected after oral DMSO-treatment in either C57BL/6- or α-synuclein transgenic F28 mice. In summary, we demonstrate that low concentrations of DMSO makes α-synuclein susceptible to undergo aggregation both in vitro and in cells. This may affect experimental outcomes when studying α-synuclein in the presence of DMSO, and should call for careful consideration when such experiments are planned.

Identification of α-Synuclein Proaggregator: Rapid Synthesis and Streamlining RT-QuIC Assays in Parkinson’s Disease

“…The control run that only contained DMSO and the aSN monomer had also formed aSN fibril, due to the self-aggregation property of aSN monomers under shaking conditions. 31 Taken together with the RT-QuIC assay results, the obtained TEM images corroborates the role of benzoxazole compounds as proaggregator for aSN monomer into aSN fibril.…”

ER stress in mouse serotonin neurons triggers a depressive phenotype alleviated by ketamine targeting eIF2α signaling

“…Other control groups of mice received locally 1 μL of aCSF or DMSO (4% in aCSF) in DR, and no observable behavioral changes such as drinking, eating, or differences in TST immobility time or neuronal survival assessed using NeuN marker were detected in both experimental groups ( Figure S1 ), as previously reported. 47 , 48 , 49 Tm-treated mice showed an increased immobility time in the TST at 1 and 3 days after infusion ( Figure 2 B), and evoked anxious-like behavior in the dark-light box (DLB, 3 days later) compared to vehicle-treated mice ( Figure 2 C). None of these behaviors were associated with abnormal locomotor activity in the open field test (OFT) ( Figure 2 D).…”

Thein vitrodynamics of pseudo-vascular network formation

“…We noted in initial testing that 0.1% DMSO affects the pseudo-vascular network evolution of all cell lines tested (Supplementary Figure 3), likely due to its effect on cell-to-cell and cell-to-matrix adhesion as DMSO can trigger cell aggregation [28]. Pseudo-vascular network inhibition has been reported before in endothelial cells for DMSO concentrations above 1% [29], however, the descriptive spatiotemporal analysis of this study shows that DMSO impacts cells even in lower concentrations and therefore, the tube assay protocol was optimized for 0.01% DMSO, that served as the control condition.…”