Dysfunction of SERCA pumps as novel mechanism of methylglyoxal cytotoxicity.
Cell Calcium
; 74: 112-122, 2018 09.
Article
en En
| MEDLINE
| ID: mdl-30015246
A novel pathway of methylglyoxal (MGX)-induced apoptosis via sarcoplasmic reticulum Ca2+-ATPase (SERCA) is presented. Interaction of SERCA1 with MGX was investigated by molecular docking and experimentally in a cell-free system. MGX concentration- and time-dependently decreased SERCA1 activity. A significant increase of sarcoplasmic reticulum (SR) carbonylation was found in the concentration range of 1-10â¯mM caused by MGX and a decrease of thiol groups at the concentrations of 5 and 40â¯mM. Affinities of SERCA1 to ATP and Ca2+ were not influenced by MGX, however decreases of Vmax related to both binding sites were observed. Molecular docking indicated binding of MGX at the cytosolic region of SERCA1, inducing conformational changes in the cytosolic-transmembrane interface. This interaction resulted in conformational changes in the cytosolic region (FITC fluorescence decrease) as well as in the transmembrane region of SERCA1 (Trp fluorescence decrease) without direct binding to the cytosolic ATP or transmembrane Ca2+ binding sites. Regarding the MGX inhibitory effect in a cell-free system and similarities of SERCA1 to its other isoforms, proapoptotic properties of MGX may be expected in cellular systems. At cellular level, MGX induced a decrease of SERCA2b expression in the pancreatic INS-1E ß-cell line. This was accompanied by cell viability decrease, increase in apoptosis, impaired insulin secretion and elevation of basal intracellular Ca2+ levels. Decreased expression of SERCA2b may contribute to induction of apoptosis of pancreatic ß-cells.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Piruvaldehído
/
Músculo Esquelético
/
Citotoxinas
/
ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico
Límite:
Animals
Idioma:
En
Revista:
Cell Calcium
Año:
2018
Tipo del documento:
Article
Pais de publicación:
Países Bajos