Hypoxia causes pancreatic ß-cell dysfunction and impairs insulin secretion by activating the transcriptional repressor BHLHE40.
EMBO Rep
; 24(8): e56227, 2023 08 03.
Article
em En
| MEDLINE
| ID: mdl-37341148
ABSTRACT
Hypoxia can occur in pancreatic ß-cells in type 2 diabetes. Although hypoxia exerts deleterious effects on ß-cell function, the associated mechanisms are largely unknown. Here, we show that the transcriptional repressor basic helix-loop-helix family member e40 (BHLHE40) is highly induced in hypoxic mouse and human ß-cells and suppresses insulin secretion. Conversely, BHLHE40 deficiency in hypoxic MIN6 cells or ß-cells of ob/ob mice reverses defects in insulin secretion. Mechanistically, BHLHE40 represses the expression of Mafa, encoding the transcription factor musculoaponeurotic fibrosarcoma oncogene family A (MAFA), by attenuating the binding of pancreas/duodenum homeobox protein 1 (PDX1) to its enhancer region. Impaired insulin secretion in hypoxic ß-cells was recovered by MAFA re-expression. Collectively, our work identifies BHLHE40 as a key hypoxia-induced transcriptional repressor in ß-cells that inhibit insulin secretion by suppressing MAFA expression.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Diabetes Mellitus Tipo 2
/
Células Secretoras de Insulina
Tipo de estudo:
Etiology_studies
/
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Revista:
EMBO Rep
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Japão