We still have more to learn about the pituitary cells regulating puberty and reproduction.
Karine Rizzoti, research scientist in the stem cell biology and developmental genetics lab at the Francis Crick Institute, examines.
Karine Rizzoti completed her Ph.D. at the University Paul Sabatier in Toulouse, France, where she studied cell movements during early embryonic development. She then moved to London to join the laboratory of Robin Lovell-Badge, initially at the National Institute for Medical Research, which later became part of the Francis Crick Institute. Her research gradually focused on the development and function of the neuroendocrine hypothalamo-pituitary axis. She contributed to the discovery of pituitary stem cells and investigated aspects of their biology, examining mechanisms underlying cell fate acquisition in both embryonic and postnatal contexts.
Origins of Pituitary Glands Regulating Puberty and Reproduction
The pituitary is a small gland located in the middle of the head and controlled by the brain. It acts on other endocrine glands like the gonads through hormones released into circulation. Different cell types produce these hormones; for example, gonadotrophs produce LH and FSH, which act on the gonads to regulate germ cell and steroid hormone production.
During embryonic development, all pituitary hormonal cell types form. After birth, the gland grows, increasing hormone-producing cell numbers. It also contains stem cells able to self-renew and differentiate into any hormonal cell type. However, in mice, where we study them, their role remains unclear because they do not appear to give to new hormonal cells, at least in normal adults.
We have now found that starting just after birth, pituitary stem cells give rise almost exclusively to gonadotrophs during a period encompassing minipuberty, a preparatory phase of reproductive system development. These new gonadotrophs constitute most of the adult population. However, embryonically formed gonadotrophs persist, confined to a small domain in the adult gland.
We still do not know what prompts pituitary stem cells to differentiate into gonadotrophs. Neither signals from the brain, nor from the gonads, which are known to act on gonadotrophs, seem to be involved.
Whether the two populations perform different roles, or if this dual origin helps to better understand diseases affecting puberty remain to be investigated. Minipuberty has been defined as a window of opportunity for these diseases. We have now shown that this is the period during which most gonadotrophs are formed, confirming its relevance for diagnosis and intervention.
Read More:
[Nature] – Gonadotrophs have a dual origin, with most derived from early postnatal pituitary stem cells
