The long-term effects of progesterone-only contraceptives on endometrium and ovary in rats

The effects of progesterone on the healing of obstetric anal sphincter damage in female rats

We aimed to evaluate the effects of postpartum progesterone on obstetric anal sphincter injury (OASI) healing in female rats using an experimental OASI model. Twenty-eight female rats were divided into four groups after birth: sham-30, sham-90, progesterone (P4)-30, and P4-90. Moreover, OASI model was established in all groups. Subsequently, except for the sham groups, medroxyprogesterone acetate (0.15 mg) was intramuscularly injected into the P4 groups. After 30 and 90 days, the rats were euthanized under general anesthesia after recording the data. The anal sphincter region was collected for histopathological examination. Progesterone and thiol/disulfide homeostasis studies were performed on blood samples. No significant differences were observed between the groups regarding the external anal sphincter (EAS), internal anal sphincter (IAS), or connective tissue thickness (p = 0.714, p = 0.135, and p = 0.314, respectively). No statistically significant differences in the total thiol, native thiol, disulfide, and progesterone levels were found between the groups (p = 0.917, p = 0.503, p = 0.361, and p = 0.294, respectively). The endometrial thickness was lower in the P4 groups than in the sham groups (p = 0.031). Postpartum progesterone administration did not affect IAS and EAS or connective tissue thickness or disrupt the thiol-disulfide balance. However, this administration led to endometrial thinning.

A rodent model of human dose-equivalent progestin-only implantable contraception

BACKGROUND

Long-acting, reversible contraceptives (LARC; progestin only) are an increasingly common hormonal contraceptive choice in reproductive aged women looking to suppress ovarian function and menstrual cyclicity. The overall objective was to develop and validate a rodent model of implanted etonogestrel (ENG) LARC, at body size equivalent doses to the average dose received by women during each of the first 3 years of ENG subdermal rod LARC use.

METHODS

Intact, virgin, female Sprague-Dawley rats (16-wk-old) were randomized to 1 of 4 groups (n = 8/group) of ENG LARC (high-0.30μg/d, medium-0.17μg/d, low-0.09μg/d, placebo-0.00μg/d) via a slow-release pellet implanted subcutaneously. Animals were monitored for 21 days before and 29 days following pellet implantation using vaginal smears, ultrasound biomicroscopy (UBM), saphenous blood draws, food consumption, and body weights. Data were analyzed by chi-square, non-parametric, univariate, and repeated measures 2-way ANOVA.

RESULTS

Prior to pellet implantation there was no difference in time spent in estrus cycle phases among the treatment groups (p > 0.30). Following pellet implantation there was a dose-dependent impact on the time spent in diestrus and estrus (p < 0.05), with the high dose group spending more days in diestrus and fewer days in estrus. Prior to pellet insertion there was not an association between treatment group and estrus cycle classification (p = 0.57) but following pellet implantation there was a dose-dependent association with cycle classification (p < 0.02). Measurements from the UBM (ovarian volume, follicle count, corpora lutea count) indicate an alteration of ovarian function following pellet implantation.

CONCLUSION

Assessment of estrus cyclicity indicated a dose-response relationship in the shift to a larger number of acyclic rats and longer in duration spent in the diestrus phase. Therefore, each dose in this model mimics some of the changes observed in the ovaries of women using ENG LARC and provides an opportunity for investigating the impacts on non-reproductive tissues in the future.

Dissecting the mechanism of Yuzhi Zhixue granule on ovulatory dysfunctional uterine bleeding by network pharmacology and molecular docking

Background

Yuzhi Zhixue Granule (YZG) is a traditional Chinese patent medicine for treating excessive menstrual flow caused by ovulatory dysfunctional uterine bleeding (ODUB) accompanied by heat syndrome. However, the underlying molecular mechanisms, potential targets, and active ingredients of this prescription are still unknown. Therefore, it is imperative to explore the molecular mechanism of YZG.

Methods

The active compounds in YZG were screened by the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). The putative targets of YZG were collected via TCMSP and Search Tool for Interacting Chemicals (STITCH) databases. The Therapeutic Target Database (TTD) and Pharmacogenomics Knowledgebase (PharmGKB) databases were used to identify the therapeutic targets of ODUB. A protein–protein interaction (PPI) network containing both the putative targets of YZG and known therapeutic targets of ODUB was built. Furthermore, bioinformatics resources from the database for annotation, visualization and integrated discovery (DAVID) were utilized for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Finally, molecular docking was performed to verify the binding effect between the YZG screened compounds and potential therapeutic target molecules.

Results

The study employed a network pharmacology method, mainly containing target prediction, network construction, functional enrichment analysis, and molecular docking to systematically research the mechanisms of YZG in treating ODUB. The putative targets of YZG that treat ODUB mainly involved PTGS1, PTGS2, ALOX5, CASP3, LTA4H, F7 and F10. The functional enrichment analysis suggested that the produced therapeutic effect of YZG against ODUB is mediated by synergistical regulation of several biological pathways, including apoptosis arachidonic acid (AA) metabolism, serotonergic synapse, complement and coagulation cascades and C-type lectin receptor signaling pathways. Molecular docking simulation revealed good binding affinity of the seven putative targets with the corresponding compounds.

Conclusion

This novel and scientific network pharmacology-based study holistically elucidated the basic pharmacological effects and the underlying mechanisms of YZG in the treatment of ODUB.

Nexplanon: the new implant for long-term contraception. A comprehensive descriptive review

Nexplanon(®) is a new long-term reversible contraception method. The current review is aimed to analyze the published data concerning the contraceptive effectiveness of Nexplanon(®) and its effects on reproductive function. Pharmacological properties and technical procedures of insertion and removal, as well as the efficacy and safety data available, were discussed. Possible strategies for treating Nexplanon(®)-related bleeding were also described. With regard to the future research and the future scientific developments of contraceptive implants, the possible use of Nexplanon(®) wide-ranging for the symptomatic treatment of endometriosis and premenstrual syndrome (PMS) were considered. Finally, it was defined in which women the use of Nexplanon(®) is indicated and in which it is contra-indicated.

Apoptosis induction and inhibition of hyperplasia formation by 2-[piperidinoethoxyphenyl]-3-[4-hydroxyphenyl]-2H-benzo(b)pyran in rat uterus

OBJECTIVE

The study was undertaken to explore the antiproliferative mechanism of action of 2-[piperidinoethoxyphenyl]-3-[4-hydroxyphenyl]-2H-benzo(b)pyran (K-1) in estradiol-induced rat uterine hyperplasia.

STUDY DESIGN

Adult ovariectomized rats received vehicle or estradiol alone (20 μg/kg) or estradiol along with K-1 (100 or 200 μg/kg) for 14 days. Uterine histomorphometric analysis and immunoblotting were performed. Caspase-3 activity and terminal deoxynucleotidyl transferase-mediated nick end-labeling staining were performed to analyze the apoptotic potential of compound.

RESULTS

Compound inhibited estradiol-induced uterine weight and histomorphometric changes pertaining to endometrial growth and down-regulated the expression of estrogen response element and activator protein-1 regulated genes and transcription factors. The compound significantly induced apoptosis, interfered with Akt activation, decreased X-linked inhibitor of apoptosis protein expression leading to an increased cleavage of caspase-9, caspase-3, poly(adenosine diphosphate-ribose) polymerase, increased Bax/Bcl2 ratio, and caspase-3 activity.

CONCLUSION

K-1 inhibits endometrial proliferation via nonclassical estrogen receptor signaling mechanisms. It interfered with Akt activation and induced apoptosis via the intrinsic pathway and inhibited estradiol-induced hyperplasia formation in rat uterus.