Contribution of apoptosis to the phenotypic changes of adrenocortical cells in primary culture.
The aim of this study was to evaluate the occurrence and physiological consequences of apoptosis in primary cultures of bovine adrenocortical cells (of fasciculata-reticularis origin). Under ACTH-free culture conditions, we observed apoptotic cells in the cell layer and the accumulation of apoptotic bodies in the culture medium. These were hardly detectable in ACTH-supplemented cultures. Under ACTH-free conditions, the DNA content of apoptotic bodies collected over 48 h represented up to 10-15% of that of the cell layer at the onset of the culture (as compared to 3% in ACTH-supplemented cultures). Past the fourth day of culture in the absence of ACTh, most cells lacked several markers of their originating fasciculata-reticularis phenotype and progressively evolved to an undifferentiated phenotype. The vast majority of the apoptotic bodies released during the first 4 days of culture were immunoreactive for P450 17 alpha. Inversely, during the same period of time, the proliferating cells (PCNA-positive) did not appear to express P450 17 alpha. Therefore, apoptosis could contribute, together with dedifferentiation, to the phenotype shift observed in ACTH-depleted cultures of adrenal fasciculata-reticularis cells. These observations also characterize this endocrine cell system as an in vitro model for the study of hormone-repressed apoptosis.
Negoescu
A
A
INSERM Unité 244, CEA, DBMS/BRCE, Centre d'Etudes Nucléaires, Grenoble, France.
Labat-Moleur
F
F
Defaye
G
G
Mezin
P
P
Drouet
C
C
Brambilla
E
E
Chambaz
E M
EM
Feige
J J
JJ
D000302:Adrenal Cortex / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D000324:Adrenocorticotropic Hormone / Q000008:administration & dosage / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis; D002417:Cattle; D002452:Cell Count; D002454:Cell Differentiation; D002478:Cells, Cultured; D002843:Chromatin / Q000648:ultrastructure; D019405:Cytochrome P-450 CYP11B2; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D008854:Microscopy, Electron; D010641:Phenotype; D013252:Steroid 11-beta-Hydroxylase / Q000378:metabolism
D002843:Chromatin; D000324:Adrenocorticotropic Hormone; D004247:DNA; D003577:Cytochrome P-450 Enzyme System; D019405:Cytochrome P-450 CYP11B2; D013252:Steroid 11-beta-Hydroxylase