Thyroid transcription factor-1 in orbital adipose tissues: potential role in orbital thyrotropin receptor expression.
Thyroid
; 15(5): 422-6, 2005 May.
Article
en En
| MEDLINE
| ID: mdl-15929662
Thyroid transcription factor-1 (TTF-1) is required for maximal expression of thyrotropin receptor (TSHR) in the thyroid. Extrathyroidal TSHR expression is detectable in normal orbital adipose tissues, with increased levels found in orbital tissues from patients with Graves' ophthalmopathy (GO), and in orbital preadipocyte cultures following differentiation. In order to determine whether TTF-1 might be involved in orbital TSHR expression, we used quantitative real-time polymerase chain reaction (PCR) to assess relative expression of this and other thyroid-associated transcription factors (TTF-2 and Pax-8) in GO orbital tissue specimens (n = 28) and cultures (n = 3), and in normal orbital tissues (n = 19) and cultures (n = 3). We detected TTF-1 and TTF-2 mRNA in GO and normal orbital tissue samples, with no difference in levels noted between the tissues. In the GO orbital cultures, TTF-1 mRNA was higher in differentiated than in control (undifferentiated) cultures (p < 0.05), while TTF-2 was unchanged. In the normal cultures, neither TTF-1 nor TTF-2 mRNA levels increased in differentiated cultures. Pax8 was undetectable in all orbital tissues and cell cultures. The presence of mRNA encoding TTF-1 in orbital tissues and cultures suggest that this transcription factor may play an important role in extrathyroidal, as it does in thyroidal, TSHR expression.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Órbita
/
Factores de Transcripción
/
Receptores de Tirotropina
/
Proteínas Nucleares
/
Tejido Adiposo
Límite:
Humans
Idioma:
En
Revista:
Thyroid
Asunto de la revista:
ENDOCRINOLOGIA
Año:
2005
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
Estados Unidos