Ovarian steroids regulate 24p3 expression in mouse uterus during the natural estrous cycle and the preimplantation period

Abstract

We examined 24p3 expression in the mouse uterus at various stages of the natural estrous cycle and during the preimplantation period. The level of 24p3 mRNA appeared intensively in proestrus and estrus, then declined sharply from metestrus to diestrus. Consistent with this observation, 24p3 protein was abundant in proestrus, decreased from estrus to metestrus and declined to a very low level in diestrus. The uterine 24p3 expression closely overlapped with the estradiol (E 2 ) surge in proestrus and estrus but it was suppressed when progesterone (P 4 ) rose to a high level during the reproductive cycle. Neither the protein nor its message was detected in the uteri of immature mice or ovariectomized adult animals. While an injection of P 4 to these animals was unable to initiate uterine 24p3 expression, administration of estrogenic steroids to these animals markedly stimulated the gene expression. Treatment of these animals with E 2 together with P 4 , on the other hand, did not stimulate the gene expression. In pregnant animals (day 1 (D1)=day of vaginal plug), 24p3 mRNA remained at a high level on D1 and D2 but dropped to an almost undetectable level on D3 and D4. This was accompanied by a decrease in 24p3 protein from D1 to D2 and a decline in the protein to undetectable levels from D3 to D4. The staining patterns of both the immunohistochemical localization of 24p3 protein and in situ hybridization for the detection of 24p3 mRNA in the uterine sections showed that 24p3 expression took place mainly in the luminal and glandular epithelial cells of the endometrium. This together with our previous observation that 24p3 protein is found in uterine luminal fluid indicates that the protein is secreted primarily from these cells to their respective luminal surfaces during proestrus and estrus.

Early diagnosis of pancreatic cancer: neutrophil gelatinase-associated lipocalin as a marker of pancreatic intraepithelial neoplasia

“…The observation that induction of NGAL correlates with apoptosis led to the hypothesis that NGAL is a pro-apoptotic factor (Huang et al, 1999;Ryon et al, 2002). This hypothesis was furthered strengthened by the observation that NGAL induced the apoptosis of neutrophils through an autocrine pathway (Devireddy et al, 2001).…”

The relationship between circulating neutrophil gelatinase-associated lipocalin and early alteration of metabolic parameters is associated with dietary saturated fat intake in non-diabetic Korean women

“…NGAL was reported to participate in various functions, including apoptosis and innate immunity, but primarily in the response to bacterial infection [19,20]. NGAL is also expressed in multiple tissues such as kidney, liver, uterus, and bone marrow [21][22][23]. Several reports have suggested that NGAL is a sensitive biomarker for various forms of kidney injuries [24][25][26].…”

Lipocalin 2 induces the epithelial–mesenchymal transition in stressed endometrial epithelial cells: possible correlation with endometriosis development in a mouse model

“…We previously showed that LCN2 mediates autocrine signaling within the endometrial epithelium (Huang et al 1999, Lee et al 2012. As LCN2 is a stress protein (Lin et al 2007), we used a 1% FBS culture medium, which causes nutrient-deprivation stress, to induce LCN2 production.…”