Cyclometalated Iridium(III) Complex-Cationic Peptide Hybrids Trigger Paraptosis in Cancer Cells via an Intracellular Ca2+ Overload from the Endoplasmic Reticulum and a Decrease in Mitochondrial Membrane Potential.
Molecules
; 26(22)2021 Nov 21.
Article
em En
| MEDLINE
| ID: mdl-34834120
ABSTRACT
In our previous paper, we reported that amphiphilic Ir complex-peptide hybrids (IPHs) containing basic peptides such as KK(K)GG (K lysine, G glycine) (e.g., ASb-2) exhibited potent anticancer activity against Jurkat cells, with the dead cells showing a strong green emission. Our initial mechanistic studies of this cell death suggest that IPHs would bind to the calcium (Ca2+)-calmodulin (CaM) complex and induce an overload of intracellular Ca2+, resulting in the induction of non-apoptotic programmed cell death. In this work, we conduct a detailed mechanistic study of cell death induced by ASb-2, a typical example of IPHs, and describe how ASb-2 induces paraptotic programmed cell death in a manner similar to that of celastrol, a naturally occurring triterpenoid that is known to function as a paraptosis inducer in cancer cells. It is suggested that ASb-2 (50 µM) induces ER stress and decreases the mitochondrial membrane potential (ΔΨm), thus triggering intracellular signaling pathways and resulting in cytoplasmic vacuolization in Jurkat cells (which is a typical phenomenon of paraptosis), while the change in ΔΨm values is negligibly induced by celastrol and curcumin. Other experimental data imply that both ASb-2 and celastrol induce paraptotic cell death in Jurkat cells, but this induction occurs via different signaling pathways.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Cálcio
/
Retículo Endoplasmático
/
Potencial da Membrana Mitocondrial
/
Irídio
/
Neoplasias
Limite:
Humans
Idioma:
En
Revista:
Molecules
Assunto da revista:
BIOLOGIA
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Japão