Preventing Preterm Birth: Exploring Innovative Solutions

This review examines the complexities of preterm birth (PTB), emphasizes the pivotal role of inflammation in the pathogenesis of preterm labor, and assesses current available interventions. Antibiotics, progesterone analogs, mechanical approaches, nonsteroidal anti-inflammatory drugs, and nutritional supplementation demonstrate a limited efficacy. Tocolytic agents, targeting uterine activity and contractility, inadequately prevent PTB by neglecting to act on uteroplacental inflammation. Emerging therapies targeting toll-like receptors, chemokines, and interleukin receptors exhibit promise in mitigating inflammation and preventing PTB.

Mechanism of action of Taohong Siwu decoction in the alleviation of primary dysmenorrhea

Background

As one of the most common gynecological disorders, PD significantly impacts the quality of life for women. TSD, a well-known traditional Chinese medical prescription, has gained popularity for its use in treating gynecological cold coagulation and blood stasis syndromes such as PD. However, the lack of comprehensive data hinders our understanding of its molecular mechanism.

Purpose

The objective of the present study is to investigate the therapeutic effects of TSD on PD and elucidate its plausible mechanism.

Methods

HPLC was employed to confirm the presence of the principal metabolites of TSD. The rat model of PD was induced by OT exposure following IWM and EB pretreatment, and subsequently treated with TSD via gastric gavage. The effects and potential mechanisms of TSD on PD rats were explored, encompassing general behavior, morphological alterations in the uterus and ovaries, biochemical indicators in the uterus and serum, and levels of proteins related to the PI3K/AKT signaling pathway.

Results

Gallic acid, hydroxysafflower yellow A, albiflorin, paeoniflorin, and ferulic acid were determined to be the primary active metabolites of TSD. The pharmacological studies yielded results indicating the successful establishment of the PD model in rats. Additionally, TSD demonstrated its ability to protect PD rats by ameliorating general behavior, mitigating pathological damage to uterine and ovarian tissues, and modulating the expression levels of correlated factors (PGE2, PGF2α, Ca2+, TXB2, IL-6, TNF-α, NO, and COX-2) as well as p-PI3K/PI3K and p-AKT/AKT proteins.

Conclusion

TSD exhibited protective effects against PD in rats through its interaction with multiple targets including P13K/AKT signaling pathway, indicating that TSD holds therapeutic potential for PD treatment and providing evidence supporting the rational utilization of TSD.

Synthesis of 5- and 7-hydroxy indolizidin-2-one prostaglandin-F2α modulators and activity on myometrial contractility towards development of agents for delaying preterm birth

In pursuit of more effective-labor delaying tocolytic agents, the prostaglandin F2α (PGF2α) receptor (FP) modulator PDC113.824 [(6S)-2] represents a potent lead for developing therapy to treat preterm birth. Derivatives of FP modulator (6S)-2 were synthesized, possessing respectively 5- and 7-hydroxyl groups on the indolizidin-2-one amino acid (I² aa) residue. The effects of the alcohol substituents were examined in a PGF2α-induced myometrial contraction assay. Based on knowledge of dihedral angle values of model I² aa peptides from X-ray analyses, the results of the study indicate respectively encouraging and limited potential for creating improved tocolytic agents by modifications at the 5- and 7-positions.

Effects of Modified Wenjing Decoction Combined with Online Publicity and Education on the Treatment of Primary Dysmenorrhea of Cold Coagulation and Blood Stasis

OBJECTIVE

To explore the effects of modified Wenjing decoction combined with online publicity and education on the treatment of primary dysmenorrhea of cold coagulation and blood stasis.

METHODS

The materials of 111 patients with primary dysmenorrhea of cold coagulation and blood stasis in the outpatient department (January 2019-June 2021) were collected to conduct the retrospective study. The 111 patients were randomized into treatment group (n = 59) and control group (n = 52). The control group received online publicity and education and conventional treatment, and the treatment group received online publicity and education and modified Wenjing decoction. The patients in the two groups were continuously treated for three menstrual cycles. The treatment effects, the dosage of analgesics, the scores of associated symptoms before and after treatment, and other indexes were compared between the two groups.

RESULTS

The differences in the efficacy on abdominal pain were statistically significant between the two groups (P < 0.05). Compared with the control group, the treatment group had lower scores of associated symptoms after treatment (p < 0.5). After the treatment of three menstrual cycles, 54 patients in the treatment group stopped taking ibuprofen, and the average ibuprofen dosage of the other 5 patients was (0.24 ± 0.16)g. The 52 patients in the control group still needed to take ibuprofen, and the mean dosage was (0.51 ± 0.05)g. The differences in the ibuprofen dosage between the two groups had remarkable difference (P < 0.001).

CONCLUSION

Modified Wenjing decoction combined with online publicity and education can obviously improve the clinical symptoms of the patients with primary dysmenorrhea of cold coagulation and blood stasis and reduce the dosage of analgesics. It is worth promoting and applying in practice.

Wandering beyond small molecules: peptides as allosteric protein modulators

Recent years have seen the rise of allosteric modulation as an innovative approach for drug design and discovery, efforts which culminated in the development of several clinical candidates. Allosteric modulation of many drug targets, including mainly membrane-embedded receptors, have been vastly explored through small molecule screening campaigns, but much less attention has been paid to peptide-based allosteric modulators. However, peptides have a significant impact on the pharmaceutical industry due to the typically higher potency and selectivity for their targets, as compared with small molecule therapeutics. Therefore, peptides represent one of the most promising classes of molecules that can modulate key biological pathways. Here, we report on the allosteric modulation of proteins (ranging from G protein-coupled receptors to specific protein-protein interactions) by peptides for applications in drug discovery.

The effectiveness of acupoint application of traditional Chinese medicine in treating primary dysmenorrhea: A protocol for meta-analysis and data mining

BACKGROUND

Primary dysmenorrhea (PD) is a functional disease of the female reproductive system, which has adverse effects on patients' physical and mental health and quality of life. At present, acupoint application of traditional Chinese medicine (TCM) as adjuvant therapy is undergoing clinical trials in different medical centers. However, there is no systematic review or meta-analysis to evaluate the efficacy of acupoint application of TCM in the treatment of PD. There is also a lack of systematic evaluation and analysis of acupoints and herbs.

METHODS

All randomized controlled trials related to acupoint catgut embedding therapy on PD will be searched in the following electronic databases: Cochrane Central Registry of controlled trials, PubMed, Wed of Science, EMBASE, Science Net, China Biomedical Literature Database, China Science Journal Database, China National Knowledge Infrastructure and Wan-Fang Database, from inception to May, 2021 were searched without language restrictions. The primary outcomes contain visual analog score, The Cox Menstrual Symptom Scale, while the secondary outcomes consist of adverse events and the recurrence rate. Two reviewers will independently perform data selection, data synthesis, and quality assessment. Data meeting the inclusion criteria will be extracted and analyzed by Revman v.5.3 software. Two reviewers will evaluate the study using the Cochrane collaborative bias risk tool. We will use the scoring method to assess the overall quality of the evidence supporting the main results. We will also use Spass software (version 19.0) for complex network analysis to explore the potential core prescription of acupoint application of traditional Chinese medicine in the treatment of PD.

RESULTS

This study will analyze the clinical effective rate, functional outcomes, quality of life, improvement of clinical symptoms of PD, and effective prescriptions of acupoint application for patients with PD.

CONCLUSION

Our findings will provide evidence for the effectiveness and potential treatment prescriptions of acupoint application for patients with PD.PROSPERO registration number: CRD 42021244357.

The Therapeutic Effect of Ge-Gen Decoction on a Rat Model of Primary Dysmenorrhea: Label-Free Quantitative Proteomics and Bioinformatic Analyses

Ge-Gen decoction (GGD) is widely used for the treatment of primary dysmenorrhea (PD) in China. However, the mechanisms that underlie this effect are unclear. We investigated the protective mechanism of GGD in a rat model of PD using label-free quantitative proteomics. The model was established by the administration of estradiol benzoate and oxytocin. Thirty rats were divided into three groups (ten rats/group): a control group (normal rats), a model group (PD rats), and a treatment group (PD rats treated with GGD). The serum levels of prostaglandin E2 (PGE2) and prostaglandin F2α (PGF2α) were measured by ELISA. Nanohigh-performance liquid chromatography-tandem mass spectrometry (nano-HPLC-MS/MS) was used to identify differentially expressed proteins (DEPs), and bioinformatics was used to investigate the protein function. Proteomic data were validated by western blot analysis. Oxytocin-induced writhing responses and abnormal serum levels of PGE2 and PGF2α were reversed following the administration of GGD. A total of 379 DEPs were identified; 276 were identified between the control group and the model group, 144 were identified between the model group and the treatment group, and 41 were identified as DEPs that were common to all groups. Bioinformatics revealed that the DEPs between the control group and the model group were mainly associated with cellular component biogenesis and binding processes. The DEPs between the model group and the treatment group were mainly involved in the protein binding and metabolic process. The expression levels of HSP90AB1 and the phosphorylation levels of ERK, JNK, and P-p38 in the uteri of rats in the three groups were consistent with the proteomic findings; MAP kinases (ERK, JNK, and p38) are known to be involved in the production of inflammatory cytokines and oxytocin signaling while HSP90AB1 is known to be associated with estrogen signaling. Collectively, these data indicate that GGD may exert its protective function on PD by regulating the inflammatory response and signaling pathways associated with oxytocin and estrogen.

Potent and Selective Human Prostaglandin F (FP) Receptor Antagonist (BAY-6672) for the Treatment of Idiopathic Pulmonary Fibrosis (IPF)

Idiopathic pulmonary fibrosis (IPF) is a rare and devastating chronic lung disease of unknown etiology. Despite the approved treatment options nintedanib and pirfenidone, the medical need for a safe and well-tolerated antifibrotic treatment of IPF remains high. The human prostaglandin F receptor (hFP-R) is widely expressed in the lung tissue and constitutes an attractive target for the treatment of fibrotic lung diseases. Herein, we present our research toward novel quinoline-based hFP-R antagonists, including synthesis and detailed structure-activity relationship (SAR). Starting from a high-throughput screening (HTS) hit of our corporate compound library, multiple parameter improvements-including increase of the relative oral bioavailability F_rel from 3 to ≥100%-led to a highly potent and selective hFP-R antagonist with complete oral absorption from suspension. BAY-6672 (46) represents-to the best of our knowledge-the first reported FP-R antagonist to demonstrate in vivo efficacy in a preclinical animal model of lung fibrosis, thus paving the way for a new treatment option in IPF.

Thyme (Thymus vulgaris [Lamiaceae]) Leaves Inhibit Contraction of the Nonpregnant Mouse Uterus

Dysmenorrhea is painful menstrual periods, which affects 25% of women within reproductive age and has a prevalence of 67.2-90.0%. Current treatment has several adverse effects and can be ineffective once the pain is initiated. Thymus vulgaris traditionally used for pain management was investigated in this study for its activity on uterine contraction in the nonpregnant uterus, as a parameter for dysmenorrhea. The dried leaves of T. vulgaris were macerated in water, and the resulting aqueous extract was investigated on the isolated mouse uterus. Parameters investigated included spontaneous contractions, oxytocin-induced contractions, and high potassium chloride (KCl; 80 mM)-induced tonic contractions. Mass spectrometric analysis of the thyme extract was also performed using liquid chromatography-high-resolution Fourier Transform mass spectrometry. Thyme extract inhibited the amplitude and frequency of spontaneous and oxytocin-induced uterine contractions. It also inhibited KCl-induced tonic contractions. The activities observed suggest that T. vulgaris inhibits uterine contractions through blockade of extracellular voltage-gated calcium channels. Secondary metabolites detected included compounds belonging to chlorogenic phytochemical class and flavonoids, which are known to have activities on extracellular calcium blockade. This study has shown that aqueous T. vulgaris extract, also known as thyme, inhibits contractions of the nonpregnant uterus and can be a lead plant in the drug discovery process for the management of dysmenorrhea.

Application of N-Dodecyl l-Peptide to Enhance Serum Stability while Maintaining Inhibitory Effects on Myometrial Contractions Ex Vivo

N-Alkylation and N-acylation of the prostaglandin-F_2α allosteric modulator l-PDC31 were performed to install various alkyl, PEG and isoprenoid groups onto the l-enantiomer of the peptide. Among the different bio-conjugates studied, the N-dodecyl analog reduced prostaglandin-F_2α-induced mouse myometrium contractions ex vivo. Furthermore, N-dodecyl-l-PDC31 exhibited improved stability in a mouse serum assay, likely due to protection from protease degradation by the lipid chain.

Confirmation of the Cardiac Safety of PGF2α Receptor Antagonist OBE022 in a First-in-Human Study in Healthy Subjects, Using Intensive ECG Assessments

OBE022, a new orally active prostaglandin F2α  receptor antagonist (OBE022) with myometrial selectivity is being developed to reduce uterine contractions during preterm labor. This first-in-human study evaluated the effect of OBE022 following multiple doses on the QT interval in 23 healthy postmenopausal women, using the effect of a meal on QTc to demonstrate assay sensitivity. We report the cardiac safety outcome performed during the multiple ascending part of this trial. OBE022 was administered after a standardized breakfast on day 1 and in the fasted state from day 3 to day 9 wth a standardized lunch 4 hours after administration. Concentration-effect modeling was used to assess the effect of prodrug OBE022 and parent OBE002 on QTc after a single dose (days 1 and 3) and multiple doses (day 9). The concentration-response analysis showed the absence of QTc prolongation at all doses tested. Two-sided 90% confidence intervals of the geometric mean Cmax  for estimated QTc effects of OBE022 and OBE002 of all dose groups were consistently below the threshold of regulatory concern. The sensitivity of this study to detect small changes in the QTc was confirmed by a significant shortening of the QTc on days 1, 3, and 9 after standardized meals. This study establishes that neither prodrug OBE022 nor parent OBE002 prolong the QTc interval. The observed food effect on the QT interval validated the assay on all assessment days. Both the change from predose, premeal and the change from premeal, postdose demonstrated the specificity of the method.

Extracts of compound Muniziqi granule suppressed uterus contraction and ameliorated oxytocin-induced primary dysmenorrhea

ETHNOPHARMACOLOGICAL RELEVANCE

Compound Muniziqi granule (CMG) is usually used as a traditional Uighur medicine to treat acne, chloasma, skin inflammation, primary dysmenorrhea (PDM), and menopausal syndrome. However, there are no sufficient data to support the clinic uses of CMG in PDM.

AIM OF THE STUDY

This work aims to examine the effect of CMG as a treatment for PDM and reveal its possible therapeutic mechanism.

MATERIALS AND METHODS

In vivo and in vitro mouse PDM models were utilized in this study. The mouse uterine contraction was induced by oxytocin after progynova or estradiol benzoate pretreatment. CMG, alkaloid extracts from seeds of Peganum harmala (AEP), and 10% and 95% ethanol extracts from seeds of Nigella glandulifera (EEN10 and EEN95) were given to mice in three doses by gavage. The writhing times within 30 min after oxytocin treatment were recorded to evaluate the analgesic effect, and the glutathione peroxidase (GSH-Px), malondialdehyde (MDA), 6-keto-prostaglandin F_1α (6-k-PGF_1α), prostaglandin F_2α (PGF_2α), thromboxane B2 (TXB₂), and nitric oxide (NO) levels in uterine tissues and PGF_2α and MDA in serum were determined. The effects (contractile curve) of CMG, AEP, EEN10, and EEN95 on uterus contraction induced by oxytocin in isolated mouse uterus were recorded.

RESULTS

In contrast to the control group, CMG, AEP, N10, and N95 could display analgesic activities dose dependently by reducing the writhing response of the PDM model mice. CMG, AEP, EEN10, and EEN95 could also remarkably decrease the level of PGF_2α, 6-k-PGF_1α, TXB₂, NO and MDA in uterine tissues and PGF_2α and MDA in serum, whereas the activity of GSH-Px in uterine tissues was increased. Furthermore, CMG, AEP, EEN10, and EEN95 could significantly inhibit the frequency and amplitude of isolated uterus induced by oxytocin in a concentration-dependent manner.

CONCLUSIONS

CMG exhibited a significant protective effect on experimental PDM. The mechanisms are probably associated with abating lipid peroxidation and over-inflammatory reaction, and alleviating the contraction of isolated mouse uterus. The seeds of P. harmala and N. glandulifera in the CMG may play an important role in exerting protective effects on PDM. This study provides pre-clinic proof to the use of CMG in clinical practice of PDM.

Behavioural and neural responses to aversive visceral stimuli in women with primary dysmenorrhoea

BACKGROUND

Chronic pelvic pain, in particular dysmenorrhoea, is a significant yet unresolved healthcare problem in gynaecology. As interoceptive sensitivity and underlying neural mechanisms remain incompletely understood, this functional magnetic resonance imaging (fMRI) study assessed behavioural and neural responses to visceral stimuli in primary dysmenorrhoea (PMD).

METHODS

Women with PMD (N = 19) without psychological comorbidity and healthy women (N = 20) were compared with respect to visceral sensory and pain thresholds, and to neural responses to individually calibrated mildly painful and painful rectal distensions implemented during scanning. Trial-by-trial ratings of perceived intensity were accomplished with visual analogue scales (VAS).

RESULTS

Although women with dysmenorrhoea reported significantly higher chronic pain intensity and pain interference with daily life activities (p < 0.01, assessed with the West Haven-Yale Multidimensional Pain Inventory), there were no differences between groups in visceral sensitivity and mean trial-by-trial VAS ratings were virtually identical. Analysis of neural responses revealed activation in brain regions previously shown to be involved in the processing of visceral stimuli with differences between painful and mildly painful stimulation, but no group differences were found even when using a liberal statistical threshold.

CONCLUSIONS

Dysmenorrhoea patients show unaltered perceptual and neural responses to experimental interoceptive stimuli. Despite limited sample size, these negative results argue against a generalized sensitization towards interoceptive stimuli in patients without psychological comorbidities. Future studies should clarify the role of psychosocial factors in central sensitization using more pain region-specific models in larger and clinically more heterogeneous samples.

SIGNIFICANCE

Despite higher chronic pain and pain interference with daily life activities, women with primary dysmenorrhoea do not differ from healthy women with respect to visceral sensitivity or neural processing of aversive interoceptive stimuli induced by rectal distensions. Generalized sensitization may be present only in subgroups with pronounced psychosocial or psychiatric disturbances.

Prostaglandin FP receptor antagonists: discovery, pharmacological characterization and therapeutic utility

In contrast to the availability of potent and selective antagonists of several prostaglandin receptor types (including DP₁ , DP₂ , EP and TP receptors), there has been a paucity of well-characterized, selective FP receptor antagonists. The earliest ones included dimethyl amide and dimethyl amine derivatives of PGF_2α , but these have failed to gain prominence. The fluorinated PGF_2α analogues, AL-8810 and AL-3138, were subsequently discovered as competitive and non-competitive FP receptor antagonists respectively. Non-prostanoid structures, such as the thiazolidinone AS604872, the D-amino acid-based oligopeptide PDC31 and its peptidomimic analogue PDC113.824 came next, but the latter two are allosteric inhibitors of FP receptor signalling. AL-8810 has a sub-micromolar in vitro potency and ≥2 log unit selectivity against most other PG receptors when tested in several cell- and tissue-based functional assays. Additionally, AL-8810 has demonstrated therapeutic efficacy as an FP receptor antagonist in animal models of stroke, traumatic brain injury, multiple sclerosis, allodynia and endometriosis. Consequently, it appears that AL-8810 has become the FP receptor antagonist of choice. LINKED ARTICLES: This article is part of a themed section on Eicosanoids 35 years from the 1982 Nobel: where are we now? To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.8/issuetoc.

OBE022, an Oral and Selective Prostaglandin F2α Receptor Antagonist as an Effective and Safe Modality for the Treatment of Preterm Labor

Preterm birth is the major challenge in obstetrics, affecting ∼10% of pregnancies. Pan-prostaglandin synthesis inhibitors [nonsteroidal anti-inflammatory drugs (NSAIDs)] prevent preterm labor and prolong pregnancy but raise concerns about fetal renal and cardiovascular safety. We conducted preclinical studies examining the tocolytic effect and fetal safety of the oral prodrug candidate OBE022 [(S)-2-amino-3-methyl-butyric acid (S)-3-{[(S)-3-(biphenyl-4-sulfonyl)-thiazolidine-2-carbonyl]-amino}-3-(4-fluoro-phenyl)-propyl ester] and its parent OBE002 [(S)-3-(biphenyl-4-sulfonyl)-thiazolidine-2-carboxylic acid [(S)-1-(4-fluoro-phenyl)-3-hydroxy-propyl]-amide], both potent and highly selective antagonist of the contractile prostaglandin F_2α (PGF_2α ) receptor (FP). Efficacy of OBE022 and OBE002, alone and in combination with other tocolytics, was assessed in human tissues and pregnant animal models for inhibition of uterine contraction and delay of parturition. Selective safety of OBE022 and/or OBE002, compared with NSAID indomethacin, was assessed on renal function, closure of the ductus arteriosus, and inhibition of platelet aggregation. In in vitro studies, OBE002 inhibited spontaneous, oxytocin- and PGF_2α -induced human myometrial contractions alone and was more effective in combination with atosiban or nifedipine. In in vivo studies, OBE022 and OBE002 reduced spontaneous contractions in near-term pregnant rats. In pregnant mice, OBE022 delayed RU486 [(8S,11R,13S,14S,17S)-11-[4-(dimethylamino)phenyl]-17-hydroxy-13-methyl-17-prop-1-ynyl-1,2,6,7,8,11,12,14,15,16-decahydrocyclopenta[a]phenanthren-3-one] -induced parturition and exerted synergistic effects in combination with nifedipine. OBE022 and/or OBE002 did not show the fetal side effects of ductus arteriosus constriction, impairment of kidney function, or inhibition of platelet aggregation observed with indomethacin. Orally active OBE022 and OBE002 exhibits potent tocolytic effects on human tissues ex vivo and animal models in vivo without causing the adverse fetal side effects seen with indomethacin. Selectively targeting the FP receptor in combination with existing tocolytics may be an effective strategy for preventing or delaying preterm delivery.

A critical role of interleukin-1 in preterm labor

Preterm birth (PTB) is a leading cause of neonatal mortality and morbidity worldwide, and represents a heavy economic and social burden. Despite its broad etiology, PTB has been firmly linked to inflammatory processes. Pro-inflammatory cytokines are produced in gestational tissues in response to stressors and can prematurely induce uterine activation, which precedes the onset of preterm labor. Of all cytokines implicated, interleukin (IL)-1 has been largely studied, revealing a central role in preterm labor. However, currently approved IL-1-targeting therapies have failed to show expected efficacy in pre-clinical studies of preterm labor. Herein, we (a) summarize animal and human studies in which IL-1 or IL-1-targeting therapeutics are implicated with preterm labor, (b) focus on novel IL-1-targeting therapies and diagnostic tests, and (c) develop the case for commercialization and translation means to hasten their development.