Mitochondrial dysfunction caused by SIRT3 inhibition drives proinflammatory macrophage polarization in obesity.
Obesity (Silver Spring)
; 31(4): 1050-1063, 2023 04.
Article
em En
| MEDLINE
| ID: mdl-36894333
ABSTRACT
OBJECTIVE:
Metabolic reprogramming is a main feature of proinflammatory macrophage polarization, a process that leads to inflammation in dysfunctional adipose tissue. Therefore, the study aim was to explore whether sirtuin 3 (SIRT3), a mitochondrial deacetylase, participates in this pathophysiological process.METHODS:
Macrophage-specific Sirt3 knockout (Sirt3-MKO) mice and wild-type littermates were treated with a high-fat diet. Body weight, glucose tolerance, and inflammation were evaluated. Bone marrow-derived macrophages and RAW264.7 cells were treated with palmitic acid to explore the mechanism of SIRT3 on inflammation.RESULTS:
The expression of SIRT3 was significantly repressed in both bone marrow-derived macrophages and adipose tissue macrophages in mice fed with a high-fat diet. Sirt3-MKO mice exhibited accelerated body weight and severe inflammation, accompanied with reduced energy expenditure and worsened glucose metabolism. In vitro experiments showed that SIRT3 inhibition or knockdown exacerbated palmitic acid-induced proinflammatory macrophage polarization, whereas SIRT3 restoration displayed opposite effects. Mechanistically, SIRT3 deficiency resulted in hyperacetylation of succinate dehydrogenase that led to succinate accumulation, which suppressed the transcription of Kruppel-like factor 4 via increasing histone methylation on its promoter, thus evoking proinflammatory macrophages.CONCLUSIONS:
This study emphasizes an important preventive role of SIRT3 in macrophage polarization and implies that SIRT3 is a promising therapeutic target for obesity.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Resistência à Insulina
/
Sirtuína 3
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article