Reproductive Sciences

The aim of the current study was to examine the effects of gonadotropin-releasing hormone agonist (GnRH-a) and antagonist (GnRH-ant) on the expression of GnRH receptor-I (GnRHR-I) in pituitary and ovaries in cyclophosphamide (CTX) chemotherapeutic rats and to investigate the possible mechanism of interventions of GnRH-a and GnRH-ant in CTX-induced ovarian damage. In total, 36 female rats were distributed into 6 groups at random: normal saline (NS) group, CTX group, GnRH-a + NS group, GnRH-a + CTX group, GnRH-ant + NS group, and GnRH-ant + CTX group. After the rats were killed, the expression of GnRHR-I messenger RNAs (mRNAs) and proteins in pituitary and ovaries were examined by reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot, respectively. The distribution of GnRHR-I in various compartments of the ovaries was observed by immunohistochemistry. Significant downregulation of GnRHR-I mRNA and protein expression in the pituitary were observed after treatment with GnRH-a or GnRH-ant. Moreover, GnRH-ant was more potent for this direct and fast inhibition. In ovary, GnRHR-I expression was significantly downregulated by GnRH-a. Although GnRH-ant slightly decreased the ovarian expression of GnRHR-I mRNA, the protein level was only weakly changed. In the ovarian compartment, GnRHR-ant groups had markedly GnRHR-I expression in early and late growing follicles compared to GnRHR-a groups that exhibited decreased expression of GnRHR-I, especially in late growing follicles. In summary, this study presents evidence for the different regulating effects of GnRH-a and GnRH-ant on the expression of GnRHR-I in pituitary and ovaries, which may provide insight into the mechanism of GnRH-a and GnRH-ant interventions on chemotoxic ovarian damage.

We seek to characterize the effect of progesterone metabolites on spontaneous and oxytocin-induced uterine contractility. Spontaneous contractility was studied in mouse uterine horns after treatment with progesterone, 2α-hydroxyprogesterone, 6β-hydroxyprogesterone (6β-OHP), 16α-hydroxyprogesterone (16α-OHP), or 17-hydroxyprogesterone caproate (17-OHPC) at 10−9 to 10−6 mol/L. Uterine horns were exposed to progestins (10−6 mol/L), followed by increasing concentrations of oxytocin (1-100 nmol/L) to study oxytocin-induced contractility. Contraction parameters were compared for each progestin and matched vehicle control using repeated measures 2-way analysis of variance. In vitro metabolism of progesterone by recombinant cytochrome P450 3A (CYP3A) microsomes (3A5, 3A5, and 3A7) identified major metabolites. Oxytocin-induced contractile frequency was decreased by 16α-OHP (P = .03) and increased by 6β-OHP (P = .05). Progesterone and 17-OHPC decreased oxytocin-induced contractile force (P = .02 and P = .04, respectively) and frequency (P = .02 and P = .03, respectively). Only progesterone decreased spontaneous contractile force (P = .02). Production of 16α-OHP and 6β-OHP metabolites were confirmed in all CYP3A isoforms tested. Progesterone metabolites produced by maternal or fetal CYP3A enzymes influence uterine contractility.

To characterize the impariment of endothelium-dependent relaxation induced by administration of the nitric oxide synthase (NOS) inhibitor Nω-L-arginine methyl ester (L-NAME) to gravid rats and to determine whether L-NAME affects nongravid rats in a similar manner. Acetylcholine (ACh; 0.01–10 μM) relaxation was studied in aortic segments (contracted with 10 nM norepinephrine) from Wistar rats that were hypertensive after receiving L-NAME (0.5 mg/mL in drinking wateR) before gravidity (hypertensive virgin rats [HVR]), during gravidity (hypertensive gravid rats [HGR]), or during the last 10 days of gravidity to 24 hours postpartum (hypertensive puerperal rats [HPR]). We also studied aortic segments from corresponding groups of untreated normotensive rats (normotensive gravid rats [NGR], normotensive puerperal rats [NPR], and normotensive virgin rats [NVR]). The approximate participations of NO and the hyperpolarizing mechanisms in ACh relaxation were calculated from the reduction of relaxation observed, respectively, after incubation with the NOS inhibitor NG-monomethyl-L-arginine (L-NMMA, 0.1 mM) or after contraction with 50 mM of potassium chloride. Expression of endothelial NOS protein was studied by Western blot in segments of HGR and NGR. Acetylcholine relaxation was reduced in HGR compared with NGR, and this reduction correlated with the severity of hypertension. In contrast, ACh relaxation in HVR was similar to that in NVR, and that of HPR was similar to that in NPR. The NO component of relaxation was reduced in HGR but preserved in the other groups. Nevertheless, there were no differences in endothelial NOS protein expression between NGR and HGR. The hyperpolarizing component in relaxation was enhanced in HVR and HPR but not HGR. Administration of L-NAME induced an impairment of endothelium-dependent relaxation, involving both nitric oxide- and hyperpolarizing-dependent mechanisms in gravid but not virgin rats; this impairment resolved with delivery.

In recent years, the matrisome, a set of proteins that make up the extracellular matrix (ECM) or are closely involved in ECM behavior, has been shown to have great importance for characterizing and understanding disease pathogenesis and progression. The matrisome is especially critical for examining diseases characterized by extensive tissue remodeling. Endometriosis is characterized by the extrauterine growth of endometrial tissue, making it an ideal condition to study through the lens of matrisome gene expression. While large gene expression datasets have become more available and gene dysregulation in endometriosis has been the target of several studies, the gene expression profile of the matrisome specifically in endometriosis has not been well characterized. In our study, we explored four Gene Expression Omnibus (GEO) DNA microarray datasets containing eutopic endometrium of people with and without endometriosis. After batch correction, menstrual cycle phase accounted for 53% of variance and disease accounted for 23%; thus, the data were separated by menstrual cycle phase before performing differential expression analysis, statistical and machine learning modeling, and enrichment analysis. We established that matrisome gene expression alone can effectively differentiate endometriosis samples from healthy ones, demonstrating the potential of matrisome gene expression for diagnostic applications. Furthermore, we identified specific matrisome genes and gene networks whose expression can distinguish endometriosis stages I/II from III/IV. Taken together, these findings may aid in developing future in vitro models of disease, offer insights into novel treatment strategies, and advance diagnostic tools for this underserved patient population.

Endometriosis is a common multifactorial disease caused by an interaction between multiple gene loci and environment. Four genome-wide association studies (GWASs) of endometriosis have identified several single-nucleotide polymorphisms (SNPs) associated with endometriosis. However, results from independent replication studies with different populations are inconsistent. The present study aims to evaluate whether the GWAS-derived susceptibility loci are correlated with the risk of the development of ovarian endometriosis in North Chinese women. This case-control study comprised 580 patients with ovarian endometriosis and 606 matched control women. Three SNPs were selected for this association study including rs10965235 in CDKN2BAS, rs2235529 located in LI NC00339-WNT4, and rs 12700667 in an intergenic region on 7p 15.2. The results show that the G/A genotype of rs 12700667 can significantly increase the risk of developing ovarian endometriosis when compared with the G/G genotype (odds ratio [OR] = 1.57, 95% confidence interval [CI] = 1.23–2.00). Similarly, the carriers with A allele showed a higher risk of ovarian endometriosis than those with G allele (OR = 1.23, 95% CI = 1.12–1.68). The study suggests that the endometriosis-associated genetic polymorphisms (rs 12700667) from GWAS be associated with the risk of developing ovarian endometriosis in North Chinese women.

Endometriosis is a benign gynecologic disorder causing dysmenorrhea, pelvic pain, and subfertility. Receptors for the growth hormone-releasing hormone (GHRH) were found in endometriotic tissues. Antagonists of GHRH have been used to inhibit the growth of endometriotic endometrial stromal cells. In this study, the GHRH receptor splice variant (SV) 1 was detected in human endometrial tissue samples by Western blots and quantitative reverse transcription polymerase chain reaction (qRT-PCR). The highest messenger RNA (mRNA) and protein levels of SV1 were found in eutopic endometrium from patients with endometriosis compared to ectopic endometriotic tissues and endometrium from normal patients. The highest expression for GHRH mRNA was found by qRT-PCR in ectopic endometriosis lesions. In an in vivo mouse model with human endometrial explants from patients with endometriosis, 10 μg MIA-602 per day resulted in significantly smaller human endometrial xenotransplants after 4 weeks compared to mice treated with vehicle. The endometrial tissues expressed SV1 before and after xenotransplantation. The proliferation of endometrial stromal cells as well as the endometriosis cell lines 12-Z and 49-Z was decreased by exposure to 1 μM MIA-602 after 72 hours. The protein levels of epithelial growth factor receptors in 12-Z and 49-Z cell lines were reduced 48 and 72 hours after the administration of 1 μM MIA-602. MIA-602 decreased the activation of the MAP-kinases ERK-1/2. Our study demonstrates the presence of SV1 receptor as a target for treatment with GHRH antagonist in endometriosis. Endometrial tissues respond to MIA-602 with inhibition of proliferation in vitro and in vivo. The use of MIA-602 could be an effective supplement to the treatment strategies in endometriosis.

Gestational diabetes, obesity, and excessive weight gain are known independent risk factors for the birth of a large for gestational age (LGA) infant. However, only 1 of the 10 infants born LGA is born by mothers with diabetes or obesity. Thus, the aim of the present study was to compare placental gene expression between healthy, nondiabetic mothers (n = 22) giving birth to LGA infants and body mass index-matched mothers (n = 24) giving birth to appropriate for gestational age infants. In the whole gene expression analysis, only 29 genes were found to be differently expressed in LGA placentas. Top upregulated genes included insulin-like growth factor binding protein 1, aminolevulinate δ synthase 2, and prolactin, whereas top downregulated genes comprised leptin, gametocyte-specific factor 1, and collagen type XVII α 1. Two enriched gene networks were identified, namely, (1) lipid metabolism, small molecule biochemistry, and organismal development and (2) cellular development, cellular growth, proliferation, and tumor morphology.