Cellular Trafficking of Glutathione Transferase M2-2 Between U373MG and SHSY-S7 Cells is Mediated by Exosomes

Extracellular Vesicles
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Valdes, Raúl, Alicia Armijo, Patricia Muñoz, Kjell Hultenby, Andres Hagg, Jose Inzunza, Ivan Nalvarte, Mukesh Varshney, Bengt Mannervik, and Juan Segura-Aguilar. "Cellular Trafficking of Glutathione Transferase M2-2 Between U373MG and SHSY-S7 Cells is Mediated by Exosomes." Neurotoxicity research 39, no. 2 (2021): 182-190.

The enzyme glutathione transferase M2-2, expressed in human astrocytes, increases its expression in the presence of aminochrome and catalyzes the conjugation of aminochrome, preventing its toxic effects. Secretion of the enzyme glutathione transferase M2-2 from U373MG cells, used as a cellular model for astrocytes, has been reported, and the enzyme is taken up by neuroblastoma SYSH-S7 cells and provide protection against aminochrome. The present study provides evidence that glutathione transferase M2-2 is released in exosomes from U373MG cells, thereby providing a means for intercellular transport of the enzyme. With particular relevance to Parkinson disease and other degenerative conditions, we propose a new mechanism by which astrocytes may protect dopaminergic neurons against the endogenous neurotoxin aminochrome.

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2023
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