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Abstract: Mussel‐inspired polydopamine (PD) coating represents a promising route for constructing functional materials and finely tuning or completely changing their surface properties. In this work, a mild and effective method to realize the deposition of PD on keratin‐based films is reported. Reactive oxygen species (ROS), generated by keratin films doped with a photosensitizer, e.g., Azure A (AzA), upon UV–vis and vis‐near IR irradiation, are exploited to obtain the PD coating. Interestingly, the use of vis‐near IR irradiation leads to an increased production of ROS by AzA resulting in a greater PD deposition. Compared to uncoated keratin films, the PD‐keratin coated materials show a granular but homogeneous surface and an increased hydrophilicity, maintaining the ROS generation ability of AzA. This work demonstrates a useful method to effectively and rapidly functionalize with PD materials that are sensitive to temperature, pH and UV light, such as keratin. The proposed strategy allows obtaining new multifunctional biomaterials of potential interest in tissue engineering and drug delivery; in particular, the use of PD‐keratin films for near IR laser bonding of ophthalmic tissue, which is a representative case in wound healing purpose, is shown. [ABSTRACT FROM AUTHOR]

Altered dopamine homeostasis is an accepted mechanism in the pathogenesis of Parkinson's disease. α-Synuclein overexpression and impaired disposal contribute to this mechanism. However, biochemical alterations associated with the interplay of cytosolic dopamine and increased α-synuclein are still unclear. Catecholaminergic SH-SY5Y human neuroblastoma cells are a suitable model for investigating dopamine toxicity. In the present study, we report the proteomic pattern of SH-SY5Y cells overexpressing α-synuclein (1.6-fold induction) after dopamine exposure. Dopamine itself is able to upregulate α-synuclein expression. However, the effect is not observed in cells that already overexpress α-synuclein as a consequence of transfection. The proteomic analysis highlights significant changes in 23 proteins linked to specific cellular processes, such as cytoskeleton structure and regulation, mitochondrial function, energetic metabolism, protein synthesis, and neuronal plasticity. A bioinformatic network enrichment procedure generates a significant model encompassing all proteins and allows us to enrich functional categories associated with the combination of factors analyzed in the present study (i.e. dopamine together with α-synuclein). In particular, the model suggests a potential involvement of the nuclear factor kappa B pathway that is experimentally confirmed. Indeed, α-synuclein significantly reduces nuclear factor kappa B activation, which is completely quenched by dopamine treatment. [ABSTRACT FROM AUTHOR]