Boulkroun S.,Institute National Of La Sante Et Of La Recherche Medicale Unite 970 |
Boulkroun S.,University of Paris Descartes |
Samson-Couterie B.,Institute National Of La Sante Et Of La Recherche Medicale Unite 970 |
Samson-Couterie B.,University of Paris Descartes |
And 21 more authors.
Endocrinology | Year: 2011
Aldosterone producing adenoma (APA) is the most common form of surgically curable hypertension. To further understand mechanisms involved in APA formation, we investigated the expression of molecules linked to adrenal stem/precursor cells [β-catenin, Sonic hedgehog (Shh), CD56], and nuclear receptors that play key roles in adrenocortical development and function steroidogenic factor 1, dosage-sensitive sex reversal-adrenal hypoplasia congenita critical region on the X chromosome, gene 1) in six control adrenal glands and 14 adrenals with APA and compared their expression with that of specific markers of zona glomerulosa (ZG) [CYP11B2, Disabled 2 (Dab2)]. Both Dab2 and CD56 were expressed in ZG. Although Dab2 associates uniquely with differentiated ZG cells and its expression is lost when cells transdifferentiate to zona fasciculata (ZF) cells, CD56 wasalso expressed in ZFandin aldosterone-producing cell clusters, confirming that these structures possess an intermediate phenotype between ZG and ZF cells. Shh was barely detectable in cells located to the outer part of the ZG in the control adrenal; in contrast, its expression was detected in the entireAPAandwasdramatically increased in the hyperplastic peritumoral ZG. Transcriptome profiling revealed differential expression of components of Shh signaling pathway in a subgroup of APA. Similarly, Wnt/β-catenin signaling was activated in the majority of APA as well as in the entire peritumoral adrenal cortex; however, no mutation was identified in the CTNNB1 gene that could account for β-catenin activation. Our data suggest that both APA and adjacent ZG present characteristics of stem/precursor cells; the reexpression of genes involved in fetal adrenal development could underlie excessive ZG cell proliferation and APA formation. Copyright © 2011 by The Endocrine Society. Source
Lefebvre H.,Institute National Of La Sante Et Of La Recherche Medicale Unite 982 |
Lefebvre H.,University of Rouen |
Prevost G.,Institute National Of La Sante Et Of La Recherche Medicale Unite 982 |
Prevost G.,University of Rouen |
And 2 more authors.
European Journal of Endocrinology | Year: 2013
Awide variety of autocrine/paracrine bioactive signals are able to modulate corticosteroid secretion in the human adrenal gland. These regulatory factors, released in the vicinity of adrenocortical cells by diverse cell types comprising chromaffin cells, nerve terminals, cells of the immune system, endothelial cells, and adipocytes, include neuropeptides, biogenic amines, and cytokines. A growing body of evidence now suggests that paracrine mechanisms may also play an important role in the physiopathology of adrenocortical hyperplasias and tumors responsible for primary adrenal steroid excess. These intra-adrenal regulatory systems, although globally involving the same actors as those observed in the normal gland, display alterations at different levels, which reinforce the capacity of paracrine factors to stimulate the activity of adrenocortical cells. The main modifications in the adrenal local control systems reported by now include hyperplasia of cells producing the paracrine factors and abnormal expression of the latter and their receptors. Because steroid-secreting adrenal neoplasms are independent of the classical endocrine regulatory factors angiotensin II and ACTH, which are respectively suppressed by hyperaldosteronism and hypercortisolism, these lesions have long been considered as autonomous tissues. However, the presence of stimulatory substances within the neoplastic tissues suggests that steroid hypersecretion is driven by autocrine/paracrine loops that should be regarded as promising targets for pharmacological treatments of primary adrenal disorders. This new potential therapeutic approach may constitute an alternative to surgical removal of the lesions that is classically recommended in order to cure steroid excess. © 2013 European Society of Endocrinology. Source