Protective effects of noradrenaline against tumor necrosis factor-alpha-induced apoptosis in cultured rat brown adipocytes: role of nitric oxide-induced heat shock protein 70 expression.
Int J Obes Relat Metab Disord
; 25(10): 1421-30, 2001 Oct.
Article
en En
| MEDLINE
| ID: mdl-11673761
ABSTRACT
OBJECTIVE:
To elucidate the effects and molecular mechanism(s) by means of which noradrenaline (NA) protects against the tumor necrosis factor (TNF)-alpha-induced apoptosis of brown adipocytes.DESIGN:
Brown fat precursor cells were isolated from young rats; 2.5 million cells were added to each 24-well culture plate and cultured in a defined culture medium. On day 8, the cultured cells were exposed to murine recombinant TNF-alpha and/or cycloheximide (CHX; 10 microg/ml) and/or NA and/or nitric oxide (NO) donors and/or the NO synthase inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) and/or 10 microM heat shock protein 70 (HSP70) antisense or sense oligomers. MEASUREMENTS Analysis of DNA fragmentation on agarose gel as a marker of apoptosis; reverse transcriptase-polymerase chain reaction analysis of mRNA levels; Western blotting analysis of protein levels.RESULTS:
Pretreatment of primary cultures of rat brown fat cells with micromolar concentrations of NA or the NO-donor S-nitroso-N-acetylpenicillamine (SNAP) induced the expression of HSP70 mRNA and protein, which was associated with cytoprotection against TNF-alpha plus CHX-induced apoptosis. The L-NAME inhibitor of NO synthase activity inhibited both NA-stimulated HSP70 expression and cytoprotection. Furthermore, pretreatment of brown adipocytes with an antisense oligonucleotide to HSP70 antagonized both SNAP- and NA-induced cytoprotection.CONCLUSION:
These findings demonstrate that the NO produced by NA stimulation can induce resistance to the TNF-alpha-induced apoptosis of brown adipocytes, possibly by means of the expression of HSP70.
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Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Tejido Adiposo Pardo
/
Norepinefrina
/
Apoptosis
/
Proteínas HSP70 de Choque Térmico
/
Óxido Nítrico
Límite:
Animals
Idioma:
En
Revista:
Int J Obes Relat Metab Disord
Año:
2001
Tipo del documento:
Article
País de afiliación:
Italia