Laboratory of Anatomy and Cell Biology, Department of Health Sciences, Kyorin University, Tokyo 181-8612, Japan.
Department of Clinical Laboratory, St. Marianna University Yokohama Seibu Hospital, Kanagawa 241-0811, Japan.
J Reprod Dev. 2023 Dec 8;69(6):308-316. doi: 10.1262/jrd.2023-023. Epub 2023 Sep 30.
The adenohypophysis is comprised of the anterior and intermediate lobes (AL and IL, respectively). Cluster of differentiation 9 (CD9)- and sex-determining region Y-box 2 (SOX2)-positive cells are stem/progenitor hormone-producing cells in the AL. They are located in the marginal cell layer (MCL) facing Rathke's cleft between the AL and IL (primary niche) and the parenchyma of the AL (secondary niche). We previously showed that, in rats, CD9/SOX2-positive cells in the IL side of the MCL (IL-side MCL) migrate to the AL side (AL-side MCL) and differentiate into prolactin-producing cells (PRL cells) in the AL parenchyma during pregnancy, lactation, and diethylstilbestrol treatment, all of which increase PRL cell turnover. This study examined the changes in CD9/SOX2-positive stem/progenitor cell niches and their proportions by manipulating the turnover of growth hormone (GH)- and thyroid-stimulating hormone (TSH)-producing cells (GH and TSH cells, respectively), which are Pit1 lineage cells, as well as PRL cells. After induction, the isolated CD9/SOX2-positive cells from the IL-side MCL formed spheres and differentiated into GH and TSH cells. We also observed an increased GH cell proportion upon treatment with GH-releasing hormone and recovery from continuous stress and an increased TSH cell proportion upon propylthiouracil treatment, concomitant with alterations in the proportion of CD9/SOX2-positive cells in the primary and secondary niches. These findings suggest that CD9/SOX2-positive cells have the potential to supply GH and TSH when an increase in GH and TSH cell populations is required in the adult pituitary gland.
腺垂体由前叶和中叶（分别为 AL 和 IL）组成。CD9 和性别决定区 Y 框 2（SOX2）阳性细胞是 AL 中产生激素的干细胞/祖细胞。它们位于 AL 和 IL 之间的 Rathke 裂隙（初级壁龛）的 AL 边缘细胞层（MCL）和 AL 实质中（次级壁龛）。我们之前表明，在大鼠中，MCL 中 IL 侧的 CD9/SOX2 阳性细胞（IL 侧 MCL）会迁移到 AL 侧（AL 侧 MCL），并在怀孕期间、哺乳期和己烯雌酚处理下分化为 AL 实质中的催乳素产生细胞（PRL 细胞），所有这些都会增加 PRL 细胞的周转率。这项研究通过操纵生长激素（GH）和促甲状腺激素（TSH）产生细胞（分别为 GH 和 TSH 细胞，它们是 Pit1 谱系细胞）以及 PRL 细胞的周转率，检查了 CD9/SOX2 阳性干细胞/祖细胞壁龛及其比例的变化。诱导后，从 IL 侧 MCL 分离的 CD9/SOX2 阳性细胞形成球体并分化为 GH 和 TSH 细胞。我们还观察到，用生长激素释放激素处理后 GH 细胞比例增加，连续应激恢复后 GH 细胞比例增加，促甲状腺素细胞比例增加，同时初级和次级壁龛中 CD9/SOX2 阳性细胞的比例也发生变化。这些发现表明，当成年垂体中需要增加 GH 和 TSH 细胞群体时，CD9/SOX2 阳性细胞有可能供应 GH 和 TSH。
