Abstract: A composition for preventing or treating synucleinopathies, which includes efavirenz or a salt or solvate thereof and a pharmaceutically acceptable carrier, is provided. The composition is useful in preventing or treating synucleinopathies, such as Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy, because the composition serves to hinder cell-to-cell transmission of alpha-synuclein, prevent intracellular aggregation of ?-synuclein, and inhibit transmission of aggregated ?-synuclein.

Abstract: A composition for preventing or treating synucleinopathies, which includes nevirapine or a salt or solvate thereof and a pharmaceutically acceptable carrier, is provided. The composition is useful in preventing or treating synucleinopathies, such as Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy, because the composition serves to hinder cell-to-cell transmission of ?-synuclein, prevent intracellular aggregation of ?-synuclein, and inhibit transmission of aggregated ?-synuclein.

Abstract: A composition including a substance that inhibits an expression or activity of c-src and its use in inhibiting aggregation and/or migration of ?-syn are disclosed. The composition may be a pharmaceutical composition and can be used for preventing or treating synucleinopathy. The substance can inhibit the signal transduction induced by ?-syn migrating to adjacent cells, thus mitigating the cytotoxic influence of ?-syn on the adjacent cells; and can inhibit the denaturation of monomeric ?-syn into aggregated ?-syn, which may be a major cause of synucleinopathy, and thus, can be beneficially used as a therapeutic agent for synucleinopathy.

Abstract: This invention provides a method of treating a neurodegenerative disease selected from the group consisting of Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy, comprising administering a pharmaceutically effective amount of an agent capable of suppressing expression or activity of SHP-1/-2 (Src homology region 2 domain-containing phosphatase-1/-2) or Fc?RIIB (IgG Fc receptor II-B) to a subject having the neurodegenerative disease, wherein the agent capable of suppressing expression of SHP-1/-2 or Fc?RIIB is selected from the group consisting of miRNA, siRNA, shRNA, antisense oligonucleotide, and a combination thereof capable of specifically binding to mRNA of SHP-1/-2 or Fc?RIIB, and the agent capable of suppressing activity of SHP-1/-2 or Fc?RIIB is selected from the group consisting of an antibody, an aptamer, an antagonist, and a combination thereof capable of specifically binding to a protein of SHP-1/-2 or Fc?RIIB.

Abstract: Provided are a pharmaceutical composition for preventing or treating neurodegenerative diseases including an agent capable of suppressing expression or activity of SHP-1/-2 or Fc?RIIB, a method of preventing or treating neurodegenerative diseases by administering the pharmaceutical composition, a method of screening for a therapeutic agent for neurodegenerative diseases, a diagnostic composition for neurodegenerative diseases, a diagnostic kit for neurodegenerative diseases including the diagnostic composition, and a method of providing information for the diagnosis of neurodegenerative diseases by using the diagnostic composition or kit. The agent capable of suppressing expression or activity of SHP-1/-2 or Fc?RIIB according to the present invention inhibits signal transduction caused by propagation of ?-synuclein to neighboring cells, thereby reducing cytotoxicity of ?-synuclein to neighboring cells and thus being usefully applied to a therapeutic agent for neurodegenerative diseases.