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Background: The leaves of Alchornea laxiflora are traditionally used in the south of Nigeria to prevent preterm births. Aim: This study was designed to investigate the activity of A. laxiflora on uterine contractility. Setting: The leaves of the plant were collected from forests in Egor, Benin City, Nigeria. Methods: The leaves were cleaned and extracted in methanol. The extract (0.005 mg/mL–3.5 mg/mL) was tested on spontaneous uterine contraction and on oxytocin-induced contraction in normal and Ca2+-free media. The plant extract (0.0035 mg/mL, 0.035 mg/mL, 0.35 mg/mL and 3.5 mg/mL) was tested on high KCl-induced uterine contractions (80 mM). The plant extract (3.5 mg/mL) was also studied in the presence of amiodarone and glibenclamide in separate experiments. Mass spectrometric analysis was additionally performed on the plant extract in order to identify significant secondary metabolites that may have contributed to the activity of the plant. Results: The plant extract inhibited spontaneous, oxytocin and high KCl-induced uterine contractions and also significantly inhibited (p < 0.01) oxytocin-induced uterine contraction in Ca2+-free medium. The plant extract significantly inhibited (p < 0.01 and p < 0.05) oxytocin’s amplitude in the presence of amiodarone and glibenclamide, respectively. Secondary metabolites belonging to classes of fatty acids, glycols, terpenes, flavonoid glycosides and porphyrins were identified. Conclusion: Alchornea laxiflora inhibited mouse uterine contractility possibly through interaction with potassium and calcium channels. Of the known metabolites identified, 3-deoxy-arabino-hept-2-ulosonic acid, 17-hydroxyingenol and phaeophorbide-a methyl inhibit uterine contractility and may contribute to the activity of A. laxiflora in utero.

Background: The plant Dryopteris filix-mas has been used traditionally for its uterine-stimulant effects.Aim: The current study is therefore aimed at investigating and determining the effect of the leaves of D. filix-mas on uterine contractility in vitro.Setting: Fresh leaves of D. filix-mas were collected from a river bank in the south-western part of Nigeria.Methods: The leaves of D. filix-mas were cleaned, dried and extracted in methanol. The extract (0.07 µg/mL–21.0 µg/mL) was tested on the isolated mouse uteri in order to determine activity on spontaneous-induced uterine contractions. Subsequently the extract (0.005 mg/mL and 0.05 mg/mL) was tested on oxytocin-induced contraction (0.00017 ng/mL–4.98 ng/mL) in calcium-containing media, submaximal oxytocin-induced contraction (0.116 ng/mL) in calcium-free media and in the presence of high KCl-induced uterine contractions (80 mM). The extract was also subjected to mass spectrometric determination of secondary metabolites.Results: The plant extract inhibited spontaneous-induced contractions with IC50 amplitude = 658.41 ng/mL ± 0.11 ng/mL and IC50 frequency = 175.32 ng/mL ± 0.53 ng/mL. The plant extract inhibited oxytocin-induced and high KCl-induced uterine contractions (p < 0.01 at 0.5 mg/mL). The plant extract had no effect on oxytocin-induced contractions under calcium-free conditions. Secondary metabolites belonging to classes of fatty acids, alkaloids, saponin glycosides, amino acids, limonoids, terpenes and porphyrins were identified.Conclusion: The current study reports an inhibitory effect of the plant on uterine contractility in this study, suggesting possible application as a tocolytic or as a contraceptive, as most contraceptive plants have shown uterine-relaxing effect.

Alpha-tocopherol and phylloquinone have been shown to directly modulate uterine contractility and reproductive function and may contribute to the management and treatment of reproductive disorders.

In Southern Nigeria, the leaves of Emilia coccinea (Sims) G Dons are used traditionally for birth control. This study was therefore aimed at evaluating the activities of the methanolic leaf extract of Emilia coccinea (EM) on parameters that affect reproduction as well as the acute toxic effects of the plant using nonpregnant female mice models. Leaves of EM were extracted by maceration with 99.8% methanol. Oral acute toxicity profiles were examined. The effects of EM on female reproductive cycle were determined after oral treatment with EM at 1000 and 100 mg/kg/day daily for 6 days using stilbesterol (1 mg/kg/day) and normal saline as controls. The activities of EM (1000 mg/kg/day and 100 mg/kg/day p.o) on reproductive hormones and organs were also studied using estradiol valerat (100 mg/kg/day p.o), progesterone (10 mg/kg/day s.c.), and normal saline as controls. The extract did not induce any observable toxic effect after 24 h. At 1000 mg/kg, the extract significantly shortened the estrus cycle (P < 0.05) while prolonging the estrus phase which were comparable to that observed with stilbesterol. The extract also increased uterine weight and altered the histology of uterine and ovarian tissues. The female reproductive hormones were additionally altered at 1000 mg/kg and the effects were comparable to that of estradiol valerat such as to indicate possible antifertility effects. LC‐HRFTMS analysis showed 9 putatively identified compounds with pyrrolizidine alkaloid occurring at the highest intensity among the identified compounds. In conclusion, the leaf extracts of EM has been shown in this study to exhibit antiovulatory and estrogenic activities which would support the traditional use of the plant in Nigeria.

The Multiple Endocrine Neoplasia I (MEN1) locus encodes the protein MENIN, which functions as a tumor suppressor protein in neuroendocrine tissues.Gastrinomas are neuroendocrine neoplasms that overproduce the hormone gastrin and can arise sporadically or as part of the MEN1 syndrome, in which mutations in the MEN1 gene lead to loss or inactivation of MENIN protein. Gastrin is a peptide hormone that is primarily synthesized in the gastric antrum and stimulates the secretion of histamine from enterochromaffin-like (ECL) cells and subsequently acid from parietal cells in the gastric corpus. In addition, gastrin exerts a mitogenic function primarily on ECL cells and progenitor cells in the gastric isthmus. Current studies seek to understand how MEN1 mutations generate a mutant MENIN protein that abrogates its tumor suppressor function. Mutations in the MEN1 gene are broadly distributed throughout its nine protein-coding exons, making it difficult to correlate protein structure with its function. Although disruption of the Men1 locus in mice causes functional neuroendocrine tumors in the pituitary and pancreas, gastrinomas do not develop in these transgenic animal models. Prior studies of human gastrinomas suggest that tissue-specific microenvironmental cues in the submucosal foregut may contribute to tumorigenesis by reprogramming of epithelial cells toward the neuroendocrine phenotype. Accordingly, recent studies suggest that neural crest-derived cells are also sensitive to reprogramming when MEN1 is deleted or mutated. Thus, the goal of this report is to review our current understanding of how MENIN modulates gastrin gene expression while highlighting its role in the prevention/suppression of neuroendocrine cell transformation.

Green tea is widely known for its beneficial biologic effect and there have been some reports on the beneficial effect on the reproductive system. There have however been no reports on green tea effects on uterine contractility. This study is therefore aimed at the investigation of green tea extract on the amplitude and frequency of uterine contractility. Green tea bags were macerated in boiling water for 5 min and concentrated to dryness. The extract (0.33 -1333.21 µg/mL) was tested on the isolated mouse uterus. The contractility parameters investigated included spontaneous contraction, oxytocin (60 pg/mL) induced contraction and high KCl (80 mM)-induced contraction. High resolution mass spectrometric (HRMS) determination of secondary metabolites was also performed on the extract. The extract inhibited both the amplitude and frequency of uterine contractility studied, however minimal inhibitory effect was observed with KCl-induced contraction. The HRMS analysis revealed the presence of twenty-five (25) significant compounds, 23 of which were identified and 2 were unknown. Compounds were observed to belong to a diverse range of phytochemical classes including pteridine, flavonoids, cyclitols, and coumarins, with the majority of detected compounds belonging to the flavonoid class. The results obtained in this study have shown that green tea extract inhibits uterine contractility possibly due to the presence of the flavonoids, and through interaction with calcium and/or prostaglandins.

In most research involving female reproductive function, female animals particularly mice and rats are usually employed. This may perhaps be due to their well-defined reproductive cycle (estrous cycle) as well as the ability to breed and handle them easily. The short and precise length of estrus cycle usually 4–5 days make mice models the choicest mammal when it comes to human related research. Also, they possess very short reproductive age typically 7–8 months reaching sexual maturity at weeks 4–7 following their birth. Although many similarities exist between this model and humans, however, there also exist obvious distinctions between the human female reproductive system and that of mice. Humans have average length of their reproductive or menstrual cycle of about 28–29 days with their reproductive ages between 10–40 years. These relevant differences between mice and human reproductive system constitute the limitations to the use of this models. Therefore, the scope of this chapter will be to explore the basic knowledge of laboratory mice by examining their reproductive system anatomy and physiology, the fertilization process, estrous cycle and genetic make-up. We hope that this will provide many insights to the use of animal models in female reproductive research.