Acute stimulation of glucose influx upon mitoenergetic dysfunction requires LKB1, AMPK, Sirt2 and mTOR-RAPTOR.
J Cell Sci
; 129(23): 4411-4423, 2016 12 01.
Article
en En
| MEDLINE
| ID: mdl-27793977
ABSTRACT
Mitochondria play a central role in cellular energy production, and their dysfunction can trigger a compensatory increase in glycolytic flux to sustain cellular ATP levels. Here, we studied the mechanism of this homeostatic phenomenon in C2C12 myoblasts. Acute (30â
min) mitoenergetic dysfunction induced by the mitochondrial inhibitors piericidin A and antimycin A stimulated Glut1-mediated glucose uptake without altering Glut1 (also known as SLC2A1) mRNA or plasma membrane levels. The serine/threonine liver kinase B1 (LKB1; also known as STK11) and AMP-activated protein kinase (AMPK) played a central role in this stimulation. In contrast, ataxia-telangiectasia mutated (ATM; a potential AMPK kinase) and hydroethidium (HEt)-oxidizing reactive oxygen species (ROS; increased in piericidin-A- and antimycin-A-treated cells) appeared not to be involved in the stimulation of glucose uptake. Treatment with mitochondrial inhibitors increased NAD+ and NADH levels (associated with a lower NAD+NADH ratio) but did not affect the level of Glut1 acetylation. Stimulation of glucose uptake was greatly reduced by chemical inhibition of Sirt2 or mTOR-RAPTOR. We propose that mitochondrial dysfunction triggers LKB1-mediated AMPK activation, which stimulates Sirt2 phosphorylation, leading to activation of mTOR-RAPTOR and Glut1-mediated glucose uptake.
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Bases de datos:
MEDLINE
Asunto principal:
Proteínas Serina-Treonina Quinasas
/
Proteínas Adaptadoras Transductoras de Señales
/
Metabolismo Energético
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Proteínas Quinasas Activadas por AMP
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Sirtuina 2
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Serina-Treonina Quinasas TOR
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Glucosa
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Mitocondrias
Límite:
Animals
Idioma:
En
Revista:
J Cell Sci
Año:
2016
Tipo del documento:
Article
País de afiliación:
Países Bajos