Arrest of mouse preterm labor until term delivery by combination therapy with atosiban and mundulone, a natural product with tocolytic efficacy.

There is a lack of FDA-approved tocolytics for the management of preterm labor (PL). In prior drug discovery efforts, we identified mundulone and mundulone acetate (MA) as inhibitors of in vitro intracellular Ca2+-regulated myometrial contractility. In this study, we probed the tocolytic potential of these compounds using human myometrial samples and a mouse model of preterm birth. In a phenotypic assay, mundulone displayed greater efficacy, while MA showed greater potency and uterine-selectivity in the inhibition of intracellular-Ca2+ mobilization. Cell viability assays revealed that MA was significantly less cytotoxic. Organ bath and vessel myography studies showed that only mundulone exerted inhibition of myometrial contractions and that neither compounds affected vasoreactivity of ductus arteriosus. A high-throughput combination screen identified that mundulone exhibits synergism with two clinical-tocolytics (atosiban and nifedipine), and MA displayed synergistic efficacy with nifedipine. Of these combinations, mundulone+atosiban demonstrated a significant improvement in the in vitro therapeutic index compared to mundulone alone. The ex vivo and in vivo synergism of mundulone+atosiban was substantiated, yielding greater tocolytic efficacy and potency on myometrial tissue and reduced preterm birth rates in a mouse model of PL compared to each single agent. Treatment with mundulone after mifepristone administration dose-dependently delayed the timing of delivery. Importantly, mundulone+atosiban permitted long-term management of PL, allowing 71% dams to deliver viable pups at term (>day 19, 4-5 days post-mifepristone exposure) without visible maternal and fetal consequences. Collectively, these studies provide a strong foundation for the development of mundulone as a single or combination tocolytic for management of PL.

Corrigendum: Pregnancy-related stress among pregnant women receiving tocolytic and non-tocolytic treatments where both used complementary medicine.

[This corrects the article DOI: 10.3389/fphar.2022.870659.].

Pregnancy-Related Stress Among Pregnant Women Receiving Tocolytic and Non-Tocolytic Treatments Where Both Used Complementary Medicine.

Objective: This study aimed to compare the pregnancy stress among pregnant women in receiving tocolytic and non-tocolytic treatments where both used complementary medicine. Methods: A cross-sectional survey was conducted among 35 pregnant women receiving tocolytic treatment and 35 receiving non-tocolytic treatment, where both used complementary medicine in a medical center in central Taiwan. A basic information questionnaire that contained demographic variables and types of complementary medicine used and the Pregnancy Stress Rating Scale were used for the analysis. Results: The types of complementary medicines were surveyed using the multiple-choice questionnaire. Natural products (77.5%) were most commonly used by pregnant women receiving tocolytic treatment, followed by alternative medicine (13.75%), manipulative and body-based practices (5%), and mind and body medicine (3.75%). In pregnant women who were receiving non-tocolytic treatment, natural products (59.1%) were most commonly used, followed by manipulative and body-based practices (16.4%), alternative medicine (15.4%), mind and body medicine (7.3%), and energy therapy (1.8%). According to the analysis of covariance test results, while both used complementary medicine in groups, pregnant women receiving tocolytic treatment were less stressed than those who were receiving non-tocolytic treatment (Pregnancy Stress Rating Scale score, p = 0.038), especially in dimension 2 (stress caused by infant care and changes in family relationships) (p = 0.015) and dimension 5 (stress caused by changes in physical appearance and function) (p = 0.008), which showed statistically significant differences (p < 0.05). Linear regression analysis results showed that the gestational age significantly associated with pregnancy stress (Pregnancy Stress Rating Scale score, p = 0.029; dimension 2, p = 0.016; and dimension 5, p = 0.001). Conclusion: Among both who used complementary medicine, pregnancy stress was significantly lower in pregnant women who were receiving tocolytic treatment than in those who were receiving non-tocolytic treatment. This finding can be used as a reference for future pregnant women's health studies.

Chinese Herbal Medicines Have Potentially Beneficial Effects on the Perinatal Outcomes of Pregnant Women.

Introduction: Tocolytic treatment is beneficial to pregnant women with a risk of premature labor or miscarriage. However, previous reports have shown that progestogen might not be effective and ritodrine may increase the risk of maternal vascular-related diseases. Chinese herbal products (CHP) are used as alternative therapies for pregnant women. The goal was to evaluate the efficacy of combined tocolytic therapy and CHP therapy in pregnancy outcomes for pregnant women in Taiwan. Materials and Methods: We conducted a retrospective cohort study based on the National Health Insurance Research Database. A total of 47,153 pregnant women treated with tocolytics aged 18-50 years from 2001 to 2015 were selected from two million random samples. According to the medical use of tocolytics and CHP, we divided the users into two groups: western medicine (WM) only (n = 40,961) and WM/CHP (n = 6,192) groups. A propensity score (PS)-matched cohort (6,192 pairs) was established based on baseline confounders. All participants were followed up to perinatal outcomes. Conditional logistic regression analysis was used to examine the effects of CHP use on the odds of miscarriage and preterm birth. Results: The adjusted odds ratio (OR) for premature birth in the WM/CHP group (n = 411, 6.64%) was significantly lower than in the WM group (n = 471, 7,61%) (0,86, 95% confidence interval [CI], 0.74-0.99). Further subgroup analysis based on the usage of formulae that activate blood and remove stasis or purgative formulae, the adjusted OR of preterm birth of those using these formulae was significantly lower in the WM/CHP group (n = 215, 6.32%) than that in the WM group (n = 265, 7.77%) (OR: 0.79, 95% CI: 0.65-0.96). Conclusion: We found that the combination of CHP and tocolytics can be beneficial to pregnant women in the prevention of premature birth. Further research is required to investigate causal relationships.

In vitro effects of citral on the human myometrium: Potential adjunct therapy to prevent preterm births.

BACKGROUND: Premature infants contribute to infant morbidity and mortality especially in low resource settings. Information on tocolytic and/or anti-inflammatory effects of several plant extracts, such as citral, could help prevent preterm birth cases and reduce the number of preterm infants. The aim of this study was to evaluate the in vitro tocolytic and anti-inflammatory effect of citral on myometrial tissues of the human uterus. METHODS: Myometrial samples from uteri obtained after hysterectomy were used in functional tests to evaluate the inhibitory effect of citral on PGF-2α induced contractions. The intracellular cyclic adenosine monophosphate (cAMP) levels generated in response to citral in human myometrial homogenates were measured by ELISAs. Forskolin was used as a positive control. The anti-inflammatory effect of citral was determined through the measurement of two pro-inflammatory cytokines, tumor necrosis factor-α (TNFα) and interleukin (IL)-1ß, and the anti-inflammatory cytokine IL-10, in human myometrial explants stimulated with lipopolysaccharide (LPS). RESULTS: Citral was able to induce a significant inhibition of PGF-2α induced contractions at the highest concentration level (p < .05). Citral caused a concentration-dependent increase in myometrial cAMP levels (p < .05) and a concentration-dependent decrease in LPS-induced TNFα and IL-1ß production, while IL-10 production increased significantly (p < .05). The anti-inflammatory and tocolytic effects induced by citral could be associated with an increase in cAMP levels in human myometrial samples. CONCLUSION: These properties place citral as a potentially safe and effective adjuvant agent in preterm birth cases, an obstetric and gynecological problem that requires urgent attention.

Justicia flava leaf extract potently relaxes pregnant human myometrial contractility: a lead plant for drug discovery of new tocolytic drugs.

NEW FINDINGS: What is the central question of this study? Can Justicia flava leaf extract (JF) inhibit human myometrial contractility as was previously shown in mouse myometrium? What is the main finding and its importance? JF abolished human myometrial contractions and therefore presents as a lead plant in drug discovery studies involving drugs for preterm birth. ABSTRACT: In the search for new potent therapies for preterm labour, Justicia flava leaf extract (JF) was previously shown to potently inhibit uterine contractility in both pregnant and non-pregnant mouse uterus. This study took the investigation a step further and investigated the activity of JF on pregnant human myometrial contractility. JF potently inhibited human myometrial contractility in a concentration-dependent manner. This pilot study provides evidence that JF should be further investigated as a lead plant in the drug discovery of new uterine relaxants.

Tocolytic effect of the monoterpenic phenol isomer, carvacrol, on the pregnant rat uterus.

Despite the wide application of carvacrol (CAR) in different biological and medical areas, there is still insufficient electrophysiological data on the mechanisms of action of CAR, particularly in the pregnant uterine function. The aim of this study was to evaluate the in vitro tocolytic effect of CAR on the contractility of isolated pregnant rat uterus in the presence of a calcium channel antagonist (nifedipine) and a cyclooxygenase inhibitor (indomethacin). The uteri were isolated from pregnant Wistar rats at 16-18 days of pregnancy and suspended in an isolated organ bath chamber containing a Ringer's physiological solution and aerated with 95% O2and 5% CO2. Samples were used in functional tests to evaluate the inhibitory effect of CAR at increasing concentrations on the rhythmic spontaneous, oxytocin-induced phasic, K+-induced tonic, and Ca2+-induced contractions. The differences in inhibitory concentration-50 and Emaxamong the compounds were determined using the one-way ANOVA followed by a post hoc Student-Newman-Keuls or Bonferroni test, in all casesP < 0.05 was considered statistically significant. Nifedipine was used as positive controls where required. CAR caused a significant concentration-dependent inhibition of the uterine contractions induced by the pharmaco- and electro-mechanic stimuli. We showed that the inhibitory effects of CAR depends on the type of muscle contraction stimuli, and that it acts stronger in spontaneous rhythmic activity and in contractions of isolated rat uterus induced by Ca2+. Nifedipine was more potent than CAR and indomethacin on the uterine contractility (P < 0.05), but none of them was more effective than nifedipine. Therefore, the tocolytic effect induced by CAR was associated with the blockade of the calcium channels in the pregnant rat uterus. This property placed CAR as a potentially safe and effective adjuvant agent in cases of preterm labor, an area of pharmacological treatment that requires urgent improvement.

Assessing a composite end point for new tocolytics in clinical trials: Data from 4 US integrated delivery networks.

PURPOSE: A composite end point (CE) measuring neonatal benefit was created for use in tocolytic randomized controlled trials with rates assessed using data from one referral hospital. The goal of this study was to assess wider generalizability of the CE, using data from multiple integrated delivery networks, creating a cohort of linked mother-neonate pairs to understand neonatal outcomes in a broad population. METHODS: Retrospective data on births (2001-2012) were collected from 4 US integrated delivery networks in the COMparative effectiveness PAtient Safety and Surveillance (COMPASS) Research Network, and linked mother-neonate pairs were identified. The CE was analyzed for all in-hospital singleton neonates at ≥24 weeks of gestational age (GA) born to mothers aged ≤45 years at a referral hospital or hospital with >2000 annual births. RESULTS: The CE analyses included 56 485 eligible mother-neonate pairs; frequency of the CE decreased from 89% to 66% between GA weeks 24 and 29 and further decreased to <14% for infants born >34 weeks of GA. Composite end point rates were 20% to 30% lower at 24 to 30 weeks of GA in COMPASS compared with Medical University of South Carolina but were similar by 31 weeks. CONCLUSIONS: The COMPASS Network enabled evaluation of the CE across a large population demonstrating that the CE findings could be replicated beyond a single hospital and the potential for lower CE frequency. Based on this, an adaptive design was adopted for randomized controlled trials, specifically sample size reestimation to mitigate against the risk of lower outcome rates, highlighting the use of real-world data in drug development.

Tocolytic action and underlying mechanism of galetin 3,6-dimethyl ether on rat uterus.

BACKGROUND: Galetin 3,6-dimethyl ether (FGAL) is a flavonoid isolated from aerial parts of Piptadenia stipulacea. Previously, FGAL was shown to inhibit both carbachol- and oxytocin-induced phasic contractions in the rat uterus, which was more potent with oxytocin. Thus, in this study, we aimed to investigate the tocolytic action mechanism of FGAL on the rat uterus. METHODS: Segments of rat uterus ileum were suspended in organ bath containing modified Locke-Ringer solution at 32 °C, bubbled with carbogen mixture under a resting tension of 1 g. Isotonic contractions were registered using kymographs and isometric contractions using force transducer. RESULTS: FGAL was more potent in relaxing uterus pre-contracted with oxytocin than with KCl. Additionally, FGAL shifted oxytocin-induced cumulative contractions curves to the right in a non-parallel manner, with Emax reduction, indicating a pseudo-irreversible noncompetitive antagonism of oxytocin receptors (OTR) or a downstream pathway target. Moreover, FGAL shifted CaCl2-induced cumulative contraction curves to the right in a non-parallel manner in depolarizing medium, nominally without Ca2+, with Emax reduction, suggesting the inhibition of Ca2+ influx through CaV. The relaxant potency of FGAL was reduced by CsCl, a non-selective K+ channel blocker, suggesting positive modulation of these channels. Furthermore, in presence of apamin, 4-aminopyridine, glibenclamide or 1 mM TEA+, the relaxant potency of FGAL was attenuated, indicating the participation of SKCa, KV, KATP and highlighting BKCa. Aminophylline, a non-selective phosphodiesterase (PDE) blocker, did not affect the FGAL relaxant potency, excluding the modulation of cyclic nucleotide PDEs pathway by FGAL. CONCLUSION: Tocolytic effect of FGAL on rat uterus occurs by pseudo-irreversible noncompetitive antagonism of OTR and activation of K+ channels, primarily BKCa, leading to calcium influx reduction through CaV.

The influence of maternal exposure history to virus and medicine during pregnancy on congenital heart defects of fetus.

Congenital heart disease (CHD) is the most common birth defect. It is due to dysfunction of the heart and great vessels during embryo development stage, or the channel was not closed after birth. This study focuses on investigating the influence of virus infection and medicine history during pregnancy on the incidence rate of CHD of fetus. We conducted a retrospective birth cohort study of infant born in the maternal and child health hospital of Fanyu district in Guangzhou. Five thousand three hundred eighty one cases with complete medical records, including mothers, fathers, and infants, were enrolled. The exposure history of mothers to virus and medicine from 6 months before pregnancy to prenatal examination was investigated, including mflu, mumps, measles, rubella, chickenpox, and hepatitis and antibiotics, tocolytic agent, anticonvulsants, antipyretic and analgesic, antitumor drug, folic acid supplement, and contraceptive. The relationship between virus infection and medicine history during pregnancy and CHD was analyzed. There was statistical difference between a normal group and a defected group in influenza infection and tocolytic agent and contraceptive pill. The exposure history to influenza and medicines, such as tocolytic agent and contraceptive pill, during pregnancy influenced the incidence rate of CHD of fetus.

Chemical composition and pharmacological properties of the essential oils obtained seasonally from Lippia thymoides.

CONTEXT: Lippia thymoides Mart. & Schauer (Verbenaceae) is used in folk medicine to treat wounds, fever, bronchitis, rheumatism, headaches, and weakness. OBJECTIVE: This study determinates the chemical composition of essential oils from L. thymoides, obtained at during each of the four seasons and correlates with pharmacological properties. MATERIALS AND METHODS: Essential oils were obtained by hydrodistillation and analyzed by gas chromatography coupled to mass spectroscopy (GC-MS). Antioxidant activity was determined by DPPH free radical scavenging and ß-carotene bleaching methods. The antimicrobial assays were performed by minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) methods. Isolated rat aorta and uterus, and guinea-pig trachea were utilized to evaluate relaxant potential in pre-contracted smooth muscle. RESULTS AND DISCUSSION: Essential oils from leaves of L. thymoides had the sesquiterpene ß-caryophyllene (17.22-26.27%) as the major constituent followed by borneol (4.45-7.36%), camphor (3.22-8.61%), camphene (2.64-5.66%), and germacrene D (4.72-6.18%). In vitro assays showed that these essential oils do not have antioxidant activity, have antimicrobial selectivity to Gram-positive bacteria Staphylococcus aureus (MIC = 0.004 mg/mL and MMC = 0.26-10.19 mg/mL) and Micrococcus luteus (MIC = 0.03 mg/mL and MMC = 8.43 mg/mL), relax isolated rat aorta (EC50 = 305-544 µg/mL, with endothelium; and EC50 = 150-283 µg/mL, without endothelium), and uterus (EC50 = 74-257 µg/mL), and minor potency, isolated guinea-pig trachea. CONCLUSIONS: Lippia thymoides is a source of natural products of pharmaceutical interest, being necessary additional studies to determine the substances involved in the biological activities.

Transdermal nitroglycerin for the treatment of preterm labor: a systematic review and metaanalysis.

OBJECTIVE: The purpose of this study was to evaluate the efficacy and safety of transdermal nitroglycerin as a tocolytic agent in women with preterm labor. STUDY DESIGN: We conducted a systematic review and metaanalysis of randomized controlled trials. RESULTS: Thirteen studies were included (1302 women) comparing transdermal nitroglycerin vs placebo (2 studies; n = 186); ß2-adrenergic receptor agonists (9 studies; n = 1024); nifedipine (1 study; n = 50); and magnesium sulfate (1 study; n = 42). There were no significant differences between transdermal nitroglycerin and placebo for delivery within 48 hours of the initiation of treatment or at <28, <34, or <37 weeks of gestation, adverse neonatal outcomes, and neurodevelopmental status at 24 months of life. Nevertheless, 1 study found a marginally significant reduction in the risk of a composite outcome of major neonatal morbidity and perinatal death (3/74 [4.1%] vs 11/79 [13.9%]; relative risk, 0.29; 95% confidence interval, 0.08-1.00). When compared with ß2-adrenergic receptor agonists, transdermal nitroglycerin was associated with a significant reduction in the risk of preterm birth at <34 and <37 weeks of gestation, admission to the neonatal intensive care unit, use of mechanical ventilation, and maternal side effects. There were no significant differences between transdermal nitroglycerin and nifedipine and magnesium sulfate in delivery within 48 hours of treatment and pregnancy prolongation, respectively. Overall, women who received transdermal nitroglycerin had a higher risk of headache. CONCLUSION: Although transdermal nitroglycerin appears to be more effective than ß2-adrenergic receptor agonists, the current evidence does not support its routine use as a tocolytic agent for the treatment of preterm labor. Further double-blind placebo-controlled trials are needed.