Endocrine Abstracts

The adrenal cortex functions to produce steroid hormones that are essential for life and regulate key biological processes, such as control of blood pressure, metabolism, reproduction, stress, and the immune response. In order to achieve both a rapid and precise response, the adrenal cortex employs hormonal feedforward-feedback systems that function in the context of histologically distinct adrenocortical zones. These layers, the outer zona glomerulosa (zG), intermediate zona fasciculata (zF), and inner zona reticularis (zR), produce mineralocorticoids, glucocorticoids, and androgens, respectively. Functional zonation within the adrenal cortex is established by centripetal differentiation, where multipotent progenitor cells in the mesenchymal capsule and outer zG give rise to concentric layers of differentiated cortex. Previous studies have shown that the Wnt/b-catenin signaling pathway is essential for maintaining adrenal progenitor cells and allowing for proper homeostatic renewal. This presentation will focus on more recent studies examining (1) how varying levels of Wnt/b-catenin signaling are regulated during adrenal homeostasis, (2) premature ageing and cellular senescence that result from Wnt-driven hyperproliferation, and (3) the potential role of cellular senescence in adrenal cancer and its therapeutic implications.