Progestins Upregulate FKBP51 Expression in Human Endometrial Stromal Cells to Induce Functional Progesterone and Glucocorticoid Withdrawal: Implications for Contraceptive- Associated Abnormal Uterine Bleeding

Abstract

Use of long-acting progestin only contraceptives (LAPCs) offers a discrete and highly effective family planning method. Abnormal uterine bleeding (AUB) is the major side effect of, and cause for, discontinuation of LAPCs. The endometria of LAPC-treated women display abnormally enlarged, fragile blood vessels, decreased endometrial blood flow and oxidative stress. To understanding to mechanisms underlying AUB, we propose to identify LAPC-modulated unique gene cluster(s) in human endometrial stromal cells (HESCs). Protein and RNA isolated from cultured HESCs treated 7 days with estradiol (E2) or E2+ medroxyprogesterone acetate (MPA) or E2+ etonogestrel (ETO) or E2+ progesterone (P4) were analyzed by quantitative Real-time (q)-PCR and immunoblotting. HSCORES were determined for immunostained-paired endometria of pre-and 3 months post-Depot MPA (DMPA) treated women and ovariectomized guinea pigs (GPs) treated with placebo or E2 or MPA or E2+MPA for 21 days. In HESCs, whole genome analysis identified a 67 gene group regulated by all three progestins, whereas a 235 gene group was regulated by E2+ETO and E2+MPA, but not E2+P4. Ingenuity pathway analysis identified glucocorticoid receptor (GR) activation as one of upstream regulators of the 235 MPA and ETO-specific genes. Among these, microarray results demonstrated significant enhancement of FKBP51, a repressor of PR/GR transcriptional activity, by both MPA and ETO. q-PCR and immunoblot analysis confirmed the microarray results. In endometria of post-DMPA versus pre-DMPA administered women, FKBP51 expression was significantly increased in endometrial stromal and glandular cells. In GPs, E2+MPA or MPA significantly increased FKBP51 immunoreactivity in endometrial stromal and glandular cells versus placebo- and E2-administered groups. MPA or ETO administration activates GR signaling and increases endometrial FKBP51 expression, which could be one of the mechanisms causing AUB by inhibiting PR and GR-mediated transcription. The resultant PR and/or GR-mediated functional withdrawal may contribute to associated endometrial inflammation, aberrant angiogenesis, and bleeding.

FKBP51 regulates decidualization through Ser473 dephosphorylation of AKT

“…These results agree with the finding that FKBP51 can be strongly upregulated by androgen, glucocorticoid, mineralocorticoid and progesterone signalling (Jaaskelainen et al 2011). In previous studies investigating the functions of ESCs, FKBP51 mRNA sharply increased after treatment with MPA, as confirmed by a whole genome microarray analysis (Guzeloglu Kayisli et al 2015). Studies in T-47D and HepG2 cells indicate FKBP51 gene expression is directly regulated by progesterone (Hubler et al 2003).…”

Hormonal Contraception and HIV-1 Acquisition: Biological Mechanisms

“…However, what is known from microarray and RNA sequencing and chromatin immunoprecipitation sequencing analysis of all the genes affected by progestins in a single cell type is that progestins regulate hundreds of genes involved in multiple cellular functions in target cells ( 93 – 96 ). Furthermore, gene expression profiles in response to progestins vary for different cells, can be modulated by the presence of other hormones and transcription factors, and vary between progesterone and other progestins ( 93 , 96 – 99 ). Given that progestins have progestogenic actions via the PR similar to progesterone, why might they exhibit different biological effects compared with progesterone, and to each other?…”

Solving the Puzzle: What Is the Role of Progestogens in Neovascularization?

“…Furthermore, the pharmacological effect of PR modulators and P4 antagonists has been reported to work in a cell-specific manner [ 149 ]. A study confirmed that P4 and progestins activate or repress unique genomic and proteomic profiles [ 168 ], which explains some puzzling findings in previous studies, such as that P4 uniquely affects angiogenesis while MPA affects cell migration [ 86 ]. Therefore, some conflicting outcomes are likely due to the use of different progestogen types.…”