Intermittent Hypoxia Stimulates Lipolysis, But Inhibits Differentiation and De Novo Lipogenesis in 3T3-L1 Cells.
Metab Syndr Relat Disord
; 18(3): 146-153, 2020 04.
Article
en En
| MEDLINE
| ID: mdl-31928504
ABSTRACT
Background:
Exposure to intermittent hypoxia (IH) may play a role in the development of metabolic impairments in the context of obstructive sleep apnea syndrome, probably by elevated plasma levels of free fatty acids. Employing gas-permeable cultureware to grow differentiated human and mouse adipocytes in vitro, we directly studied the effects of pericellular oxygen fluctuations on key adipocyte metabolic functions-spontaneous lipolytic rates, triglyceride accumulation, de novo lipogenesis, and expression of adipocyte-specific marker genes. Materials andMethods:
3T3-L1 fibroblasts and human subcutaneous preadipocytes were differentiated under conditions that induced repetitive pericellular-oxygen cycles IH between 1% O2 (5 min) and 16% O2 (5 min), continuously for 14 days or under control conditions. Chemicals were used to inhibit the flux of acetyl-CoA from glycolysis (alfa-cyano-4-hydroxy cinnamate) or the tricarboxylic acid cycle (SB204990), or to stimulate the flux of acetyl-CoA from pyruvate to the lipogenic pool. Lipolytic rate, intracellular lipids, and expression of adipocyte differentiation markers were assessed and t-test or ANOVA were used to find significant differences.Results:
The rate of lipolysis increased by 211% in 3T3-L1 cells and by 39% in obese human adipocytes. Exposure to IH reduced intracellular lipid stores by 37% and reduced the expression of adipocyte differentiation markers. Pharmacological stimulation or inhibition of de novo lipogenesis did not modify the intracellular lipid content under IH.Conclusions:
Pericellular oxygen fluctuations directly stimulated lipolysis, but did not increase de novo lipogenesis from endogenous substrates. Similarly, IH hampered adipocyte differentiation from precursors.Palabras clave
Texto completo:
1
Base de datos:
MEDLINE
Asunto principal:
Hipoxia de la Célula
/
Diferenciación Celular
/
Lipogénesis
/
Lipólisis
Límite:
Animals
/
Humans
Idioma:
En
Revista:
Metab Syndr Relat Disord
Asunto de la revista:
METABOLISMO
Año:
2020
Tipo del documento:
Article
País de afiliación:
República Checa