Characterization of Nuclear Progesterone Receptor Isoforms in the Term Equine Placenta

Abstract

In equine parturition, the role of progestins along with the nuclear progesterone receptor (nPR) signaling pathway in the placenta is not completely clarified. The progestins play an integral role in maintaining myometrial quiescence during the late stage of pregnancy via acting on nPR isoforms (PRA and PRB; PRB is more active than PRA). The current study aimed to determine the PRA and PRB expressions in the term equine placenta at the gene and protein levels. Six term equine placentas were used in this study. Reverse transcription polymerase chain reaction (RT-PCR) was used to quantify the mRNA expression for PRA and PRB. The protein expression was detected using the Western Blot technique. The results revealed that the mRNA and protein expressions for PRA were significantly higher (P < 0.0001) in the term equine placental tissue compared to the mRNA and protein expressions of PRB. These results demonstrated that nPRs are detectable in the term placenta of mares and PRA is the dominant isoform expressed. The present findings raised the possibility that the PRA plays an important role in the parturition process and expulsion of the placenta in mares.

Enhancement of Female Rat Fertility via Ethanolic Extract from Nigella sativa L. (Black Cumin) Seeds Assessed via HPLC-ESI-MS/MS and Molecular Docking

“…LC-MS spectral interpretation allowed for the identification of four alkaloids, magnoflorine, nigellidine, dihydronigellidine, and nigelanoid; four saponins, hederagenin, hederageninpentoside, tauroside E, and hederagenin methyl ester; three monoterpenes, thymoquinolglucoside, thymoquinone, and thymoquinolglucuronic acid; one flavonoid, kaempferol; four phenolic acids, vanillic acid, methoxy cinnamic acid, caffeic acid 3-O-glucuronide, and (E)-p-coumaric acid; and three fatty acids, marked by their MS/MS and in negative ionization mode. [M-H-Rha-Pent (308)] − due to loss of rhamnose and pentose sugar, which were suggested as hederageninpentoside (7) and tauroside E (8) (Figure S5), respectively [30][31][32] [29,30]. For compound 4, the ions were observed in the MS/MS spectra with fragment ions at m/z 310.07 [M-H-CH 3 ] − , 282.09 [M-H-CH 3 -CH-CH 3 ] − , and 163.00 [M-H-glucose (162)] − , corresponding to thymoquinolglucoside (Figure S7) [28,32].…”

“…LH triggers ovulation and the formation of corpora lutea, leading to Progesterone production [4]. P4 is crucial for maintaining pregnancy, releasing mature oocytes, and facilitating implantation [5][6][7]. E2 is essential for the growth and activation of the female reproductive system, as well Molecules 2024, 29, 735 2 of 20 as the development of secondary sex characteristics [8].…”