Novel multifunctional nanoliposomes inhibit α-synuclein fibrillization, attenuate microglial activation, and silence the expression of SNCA gene.

Introduction: The aim of this study was to compare the effect of five types of PEGlated nanoliposomes (PNLs) on α-synuclein (α-syn) fibrillization, attenuation of microglial activation, and silence of the SNCA gene, which encodes α-syn.

Methods: To evaluate the inhibition of α-syn fibrillization, we used standard in vitro assay based on Thioflavin T (ThT) fluorescence. Next, to evaluate the attenuation of microglial activation, the concentration of TNF-a and IL-6 was quantified by ELISA assay in BV2 microglia cells treated with 100nM A53T α-syn and PNLs. In order to determine the silencing of the SNCA, real-time PCR and Western blot analysis was used. Finally, the efficacy of PNLs was confirmed in a transgenic mouse model expressing human α-syn.

Results: ThT assay showed both PNL1 and PNL2 significantly inhibited a-syn fibrillization. ELISA test also showed the production of TNF-a and IL-6 was significantly attenuated when microglial cells treated with PNL1 or PNL2. We also found that SNCA gene, at both mRNA and protein levels, was significantly silenced when BV2 microglia cells were treated with PNL1 or PNL2. Importantly, the efficacy of PNL1 and PNL2 was finally confirmed in vivo in a transgenic mouse model.

Conclusions: In conclusion, the novel multifunctional nanoliposomes tested in our study inhibit α-syn fibrillization, attenuate microglial activation, and silence SNCA gene. Our findings suggest the therapeutic potential of PNL1 and PNL2 for treating synucleinopathies.