Extracellular albumin covalently sequesters selenocompounds and determines cytotoxicity

Selenocompounds (SeCs) are well-known nutrients and promising candidates for cancer therapy; however, treatment efficacy is very heterogeneous and the mechanism of action is not fully understood. Several SeCs have been reported to have albumin-binding ability, which is an important factor in determi...

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Detalles Bibliográficos
Autores: Zheng, Wenyi, Boada, Roberto|||0000-0003-4857-8402, He, Riu, Xiao, Tingting|||0000-0001-9818-8627, Ye, Fei|||0000-0002-1679-1316, Simonelli, Laura|||0000-0001-5331-0633, Valiente, Manuel|||0000-0003-0766-9922, Zhao, Ying, Hassan, Moustapha
Tipo de recurso: artículo
Fecha de publicación:2019
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:216644
Acceso en línea:https://ddd.uab.cat/record/216644
https://dx.doi.org/urn:doi:10.3390/ijms20194734
Access Level:acceso abierto
Palabra clave:Selenium
Albumin
Cytotoxicity
Cellular uptake
X-ray absorption spectroscopy
Descripción
Sumario:Selenocompounds (SeCs) are well-known nutrients and promising candidates for cancer therapy; however, treatment efficacy is very heterogeneous and the mechanism of action is not fully understood. Several SeCs have been reported to have albumin-binding ability, which is an important factor in determining the treatment efficacy of drugs. In the present investigation, we hypothesized that extracellular albumin might orchestrate SeCs efficacy. Four SeCs representing distinct categories were selected to investigate their cytotoxicity, cellular uptake, and species transformation. Concomitant treatment of albumin greatly decreased cytotoxicity and cellular uptake of SeCs. Using both X-ray absorption spectroscopy and hyphenated mass spectrometry, we confirmed the formation of macromolecular conjugates between SeCs and albumin. Although the conjugate was still internalized, possibly via albumin scavenger receptors expressed on the cell surface, the uptake was strongly inhibited by excess albumin. In summary, the present investigation established the importance of extracellular albumin binding in determining SeCs cytotoxicity. Due to the fact that albumin content is higher in humans and animals than in cell cultures, and varies among many patient categories, our results are believed to have high translational impact and clinical implications.