Enhanced drug delivery to the reproductive tract using nanomedicine reveals therapeutic options for prevention of preterm birth

New therapeutic target NCF1-directed multi-bioactive conjugate therapies prevent preterm birth and adverse pregnancy outcomes

Preterm birth (PTB) is a leading cause of neonatal morbidity and mortality worldwide, yet the cellular and molecular mechanisms driving this condition remain undeciphered, thus limiting discovery of new therapies. In-depth analyses of human and mouse tissues associated with PTB, in combination with cellular studies, indicated that aberrantly high-expressed neutrophil cytoplasmic factor (NCF) 1 leads to oxidative distress, recruitment, and pro-inflammatory activation of neutrophils and macrophages, while sequentially overexpressed pro-inflammatory mediators induce contractions of uterine smooth muscle cells (USMCs) as well as apoptosis of USMCs and amniotic epithelial cells, thereby causing PTB. According to these new findings, we rationally engineered an amphiphilic macromolecular conjugate LPA by covalently integrating low-molecular-weight heparin, a reactive oxygen species-responsive/scavenging component, and an anti-inflammatory peptide. This bioengineered macromolecular conjugate can self-assemble into multi-bioactive nanoparticles (LPA NP). In a mouse model of PTB, LPA NP effectively delayed PTB and inhibited adverse pregnancy outcomes, by regulating NCF1-mediated oxidative-inflammatory cascades, i.e., attenuating oxidative stress, inhibiting inflammatory cell activation, reducing local inflammation, and decreasing contraction/apoptosis of myometrial cells. Packaging LPA NP into temperature-responsive, self-healing, and bioadhesive hydrogel further potentiated its in vivo efficacies after intravaginal delivery, by prolonging retention time, sustaining nanotherapy release, and increasing bioavailability in the placenta/uterus. Importantly, both the conjugate/nanotherapy and hydrogel formulations exhibited excellent safety profiles in pregnant mice, with negligible side effects on the mother and offspring.

Hypotonic, gel-forming delivery system for vaginal drug administration

Vaginal drug delivery is often preferred over systemic delivery to reduce side effects and increase efficacy in treating diseases and conditions of the female reproductive tract (FRT). Current vaginal products have drawbacks, including spontaneous ejection of drug-eluting rings and unpleasant discharge from vaginal creams. Here, we describe the development and characterization of a hypotonic, gel-forming, Pluronic-based delivery system for vaginal drug administration. The rheological properties were characterized with and without common hydrogel polymers to demonstrate the versatility. Both qualitative and quantitative approaches were used to determine the Pluronic F127 concentration below the critical gel concentration (CGC) that was sufficient to achieve gelation when formulated to be hypotonic to the mouse vagina. The hypotonic, gel-forming formulation was found to form a thin, uniform gel layer along the vaginal epithelium in mice, in contrast to the rapidly forming conventional gelling formulation containing polymer above the CGC. When the hypotonic, gel-forming vehicle was formulated in combination with a progesterone nanosuspension (ProGel), equivalent efficacy was observed in the prevention of chemically-induced preterm birth (PTB) compared to commercial Crinone® vaginal cream. Further, ProGel showed marked benefits in reducing unpleasant discharge, reducing product-related toxicity, and improving compatibility with vaginal bacteria in vitro. A hypotonic, gel-forming delivery system may be a viable option for therapeutic delivery to the FRT.

Rethinking the application of nanoparticles in women's reproductive health and assisted reproduction

Nanoparticles and nanotechnology may present opportunities to revolutionize the prevention, treatment and diagnosis of a range of reproductive health conditions in women. These technologies are also used to improve outcomes of assisted reproductive technology. We highlight a range of these potential clinical uses of nanoparticles for polycystic ovary syndrome, endometriosis, uterine fibroids and sexually transmitted infections, considering in vitro and in vivo studies along with clinical trials. In addition, we discuss applications of nanoparticles in assisted reproductive technology, including sperm loading, gamete and embryo preservation and preventing preterm birth. Finally, we present some of the concerns associated with the medical use of nanoparticles, identifying routes for further exploration before nanoparticles can be applied to women's reproductive health in the clinic.

Microorganism-derived extracellular vesicles: emerging contributors to female reproductive health

Extracellular vesicles (EVs) are cell-derived nanoparticles that carry small molecules, nucleic acids, and proteins long distances in the body facilitating cell-cell communication. Microorganism-derived EVs mediate communication between parent cells and host cells, with recent evidence supporting their role in biofilm formation, horizontal gene transfer, and suppression of the host immune system. As lipid-bound bacterial byproducts, EVs demonstrate improved cellular uptake and distribution in vivo compared to cell-free nucleic acids, proteins, or small molecules, allowing these biological nanoparticles to recapitulate the effects of parent cells and contribute to a range of human health outcomes. Here, we focus on how EVs derived from vaginal microorganisms contribute to gynecologic and obstetric outcomes. As the composition of the vaginal microbiome significantly impacts women's health, we discuss bacterial EVs from both healthy and dysbiotic vaginal microbiota. We also examine recent work done to evaluate the role of EVs from common vaginal bacterial, fungal, and parasitic pathogens in pathogenesis of female reproductive tract disease. We highlight evidence for the role of EVs in women's health, gaps in current knowledge, and opportunities for future work. Finally, we discuss how leveraging the innate interactions between microorganisms and mammalian cells may establish EVs as a novel therapeutic modality for gynecologic and obstetric indications.

Regulation of 20α-Hydroxysteroid Dehydrogenase Expression in Term Pregnant Human Myometrium Ex Vivo

Metabolic inactivation of progesterone within uterine myocytes by 20α-hydroxysteroid dehydrogenase (20α-HSD) has been postulated as a mechanism contributing to functional progesterone withdrawal at term. In humans, 20α-HSD is encoded by the gene AKR1C1. Myometrial AKR1C1 mRNA abundance has been reported to increase significantly during labor at term. In spontaneous preterm labor, however, we previously found no increase in AKR1C1 mRNA level in the myometrium except for preterm labor associated with clinical chorioamnionitis. This suggests that increased 20α-HSD activity is a mechanism through which inflammation drives progesterone withdrawal in preterm labor. In this study, we have determined the effects of various treatments of therapeutic relevance on AKR1C1 expression in pregnant human myometrium in an ex vivo culture system. AKR1C1 expression increased spontaneously during 48 h culture (p < 0.0001), consistent with the myometrium transitioning to a labor-like phenotype ex vivo, as reported previously. Serum supplementation, prostaglandin F2α, phorbol myristate acetate, and mechanical stretch had no effect on the culture-induced increase, whereas progesterone (p = 0.0058) and cAMP (p = 0.0202) further upregulated AKR1C1 expression. In contrast, culture-induced upregulation of AKR1C1 expression was dose-dependently repressed by three histone/protein deacetylase inhibitors: trichostatin A at 5 (p = 0.0172) and 25 µM (p = 0.0115); suberoylanilide hydroxamic acid at 0.5 (p = 0.0070), 1 (p = 0.0045), 2.5 (p = 0.0181), 5 (p = 0.0066) and 25 µM (p = 0.0014); and suberoyl bis-hydroxamic acid at 5 (p = 0.0480) and 25 µM (p = 0.0238). We propose the inhibition of histone/protein deacetylation helps to maintain the anti-inflammatory, pro-quiescence signaling of progesterone in pregnant human myometrium by blocking its metabolic inactivation. Histone deacetylase inhibitors may represent a class of agents that preserve or restore the progesterone sensitivity of the pregnant uterus.

Acetyl-CoA metabolism as a therapeutic target for cancer

Acetyl-coenzyme A (acetyl-CoA), an essential metabolite, not only takes part in numerous intracellular metabolic processes, powers the tricarboxylic acid cycle, serves as a key hub for the biosynthesis of fatty acids and isoprenoids, but also serves as a signaling substrate for acetylation reactions in post-translational modification of proteins, which is crucial for the epigenetic inheritance of cells. Acetyl-CoA links lipid metabolism with histone acetylation to create a more intricate regulatory system that affects the growth, aggressiveness, and drug resistance of malignancies such as glioblastoma, breast cancer, and hepatocellular carcinoma. These fascinating advances in the knowledge of acetyl-CoA metabolism during carcinogenesis and normal physiology have raised interest regarding its modulation in malignancies. In this review, we provide an overview of the regulation and cancer relevance of main metabolic pathways in which acetyl-CoA participates. We also summarize the role of acetyl-CoA in the metabolic reprogramming and stress regulation of cancer cells, as well as medical application of inhibitors targeting its dysregulation in therapeutic intervention of cancers.

Nanotechnological approaches for the treatment of placental dysfunction: recent trends and future perspectives

The transitory placenta develops during pregnancy and mediates the blood flow between the mother and the developing baby. Placental dysfunction, including but not limited to placenta accreta spectrum, fetal growth restriction, preeclampsia and gestational trophoblastic disease, arises from abnormal placental development and can result in significant adverse maternal and fetal health outcomes. Unfortunately, there is a lack of treatment alternatives for these disorders. Nanocarriers offer versatility, including extended circulation, organ-specific targeting and intracellular transport, finely tuning therapeutic placental interactions. This thorough review explores nanotechnological strategies for addressing placental disorders, encompassing dysfunction insights, potential drug-delivery targets and recent strides in placenta-targeted nanoparticle (NP) therapies, instilling hope for effective placental malfunction treatment.

Nanomedicine for Maternal and Fetal Health

Conception, pregnancy, and childbirth are complex processes that affect both mother and fetus. Thus, it is perhaps not surprising that in the United States alone, roughly 11% of women struggle with infertility and 16% of pregnancies involve some sort of complication. This presents a clear need to develop safe and effective treatment options, though the development of therapeutics for use in women's health and particularly in pregnancy is relatively limited. Physiological and biological changes during the menstrual cycle and pregnancy impact biodistribution, pharmacokinetics, and efficacy, further complicating the process of administration and delivery of therapeutics. In addition to the complex pharmacodynamics, there is also the challenge of overcoming physiological barriers that impact various routes of local and systemic administration, including the blood-follicle barrier and the placenta. Nanomedicine presents a unique opportunity to target and sustain drug delivery to the reproductive tract and other relevant organs in the mother and fetus, as well as improve the safety profile and minimize side effects. Nanomedicine-based approaches have the potential to improve the management and treatment of infertility, obstetric complications, and fetal conditions.

A comparison of neonatal outcomes after taking progesterone pills and progesterone intramuscular injections in preterm labor: An RCT

Background

Approximately two-thirds of infant mortality within the first year of life are caused by preterm labor (PL).

Objective

This study aimed to investigate the effects of progesterone-based compounds to prevent PL.

Materials and Methods

This randomized clinical trial study was conducted on 146 pregnant women admitted to Department of Obstetrics and Gynecology, Afzalipour hospital in Kerman University of Medical Sciences, Kerman, Iran in June 2019. The participants with PL received Tocolytic and 12 mg Betamethasone in 2 doses over 2 days to mature the fetus's lungs. Stopping PL was considered a 12-hr period without any contractions after finishing the Tocolytic. Following the successful cessation of PL, the participants were monitored for 48 hr. Subsequently, the participants were divided into 2 groups. Participants received 200 mg Lutogel capsules orally per day in group A while group B received a weekly dose of 250 mg Proluton in the form of intramuscular injection, respectively. Treatment in groups continued until the 36th wk of delivery. The participants were followed-up weekly, and if any signs of PL were detected, an obstetrician carried out a vaginal examination.

Results

The incidence of PL was the same in both groups. There was no significant difference in the latent phase, average birth weight, and the neonatal intensive care unit admission frequency (p = 0.07, 0.17, 0.58, respectively) between groups.

Conclusion

No difference in the results obtained from theneonataloutcomes evaluated in groups. Both medications similarly led to recovering pregnancy and neonatal outcomes caused by PL. Applying the oral form with similar beneficial effects were pointed out in this study, which can be a solution to the issues caused by numerous injections that are inevitable in the injected administration of this medicine.

Cervicovaginal mucus barrier properties during pregnancy are impacted by the vaginal microbiome

Introduction

Mucus in the female reproductive tract acts as a barrier that traps and eliminates pathogens and foreign particles via steric and adhesive interactions. During pregnancy, mucus protects the uterine environment from ascension of pathogens and bacteria from the vagina into the uterus, a potential contributor to intrauterine inflammation and preterm birth. As recent work has demonstrated the benefit of vaginal drug delivery in treating women's health indications, we sought to define the barrier properties of human cervicovaginal mucus (CVM) during pregnancy to inform the design of vaginally delivered therapeutics during pregnancy.

Methods

CVM samples were self-collected by pregnant participants over the course of pregnancy, and barrier properties were quantified using multiple particle tracking. 16S rRNA gene sequencing was performed to analyze the composition of the vaginal microbiome.

Results

Participant demographics differed between term delivery and preterm delivery cohorts, with Black or African American participants being significantly more likely to delivery prematurely. We observed that vaginal microbiota is most predictive of CVM barrier properties and of timing of parturition. Lactobacillus crispatus dominated CVM samples showed increased barrier properties compared to polymicrobial CVM samples.

Discussion

This work informs our understanding of how infections occur during pregnancy, and directs the engineering of targeted drug treatments for indications during pregnancy.

Preterm labor with and without chorioamnionitis is associated with activation of myometrial inflammatory networks: a comprehensive transcriptomic analysis

BACKGROUND

The onset of preterm labor is associated with inflammation. Previous studies suggested that this is distinct from the inflammation observed during term labor. Our previous work on 44 genes differentially expressed in myometria in term labor demonstrated a different pattern of gene expression from that observed in preterm laboring and nonlaboring myometria. We found increased expression of inflammatory genes in preterm labor associated with chorioamnionitis, but in the absence of chorioamnionitis observed no difference in gene expression in preterm myometria regardless of laboring status, suggesting that preterm labor is associated with different myometrial genes or signals originating from outside the myometrium. Given that a small subset of genes were assessed, this study aimed to use RNA sequencing and bioinformatics to assess the myometrial transcriptome during preterm labor in the presence and absence of chorioamnionitis.

OBJECTIVE

This study aimed to comprehensively determine protein-coding transcriptomic differences between preterm nonlaboring and preterm laboring myometria with and without chorioamnionitis.

STUDY DESIGN

Myometria were collected at cesarean delivery from preterm patients not in labor (n=16) and preterm patients in labor with chorioamnionitis (n=8) or without chorioamnionitis (n=6). Extracted RNA from myometrial tissue was prepared and sequenced using Illumina NovaSeq. Gene expression was quantified by mapping the sequence reads to the human reference genome (hg38). Differential gene expression analysis, gene set enrichment analysis, and weighted gene coexpression network analysis were used to comprehensively interrogate transcriptomic differences and their associated biology.

RESULTS

Differential gene expression analysis comparing preterm patients in labor with chorioamnionitis with preterm patients not in labor identified 931 differentially expressed genes, whereas comparing preterm patients in labor without chorioamnionitis with preterm patients not in labor identified no statistically significant gene expression changes. In contrast, gene set enrichment analysis and weighted gene coexpression network analysis demonstrated that preterm labor with and without chorioamnionitis was associated with enrichment of pathways involved in activation of the innate immune system and inflammation, and activation of G protein-coupled receptors. Key genes identified included chemotactic CYP4F3, CXCL8, DOCK2, and IRF1 in preterm labor with chorioamnionitis and CYP4F3, FCAR, CHUK, and IL13RA2 in preterm labor without chorioamnionitis. There was marked overlap in the pathways enriched in both preterm labor subtypes.

CONCLUSION

Differential gene expression analysis demonstrated that myometria from preterm patients in labor without chorioamnionitis and preterm patients not in labor were transcriptionally similar, whereas the presence of chorioamnionitis was associated with marked gene changes. In contrast, comprehensive bioinformatic analysis indicated that preterm labor with or without chorioamnionitis was associated with innate immune activation. All causes of preterm labor were associated with activation of the innate immune system, but this was more marked in the presence of chorioamnionitis. These data suggest that anti-inflammatory therapy may be relevant in managing preterm labor of all etiologies.

MYB and ELF3 differentially modulate labor-inducing gene expression in myometrial cells

Spontaneous uterine contractions are initiated when smooth muscle cells (SMCs) within the uterine muscle, or myometrium, transition from a functionally dormant to an actively contractile phenotype at the end of the pregnancy period. We know that this process is accompanied by gestational time point-specific differences in the SMC transcriptome, which can be modulated by the activator protein 1 (AP-1), nuclear factor kappa beta (NF-κβ), estrogen receptor (ER), and progesterone receptor (PR) transcription factors. Less is known, however, about the additional proteins that might assist these factors in conferring the transcriptional changes observed at labor onset. Here, we present functional evidence for the roles of two proteins previously understudied in the SMC context-MYB and ELF3-which can contribute to the regulation of labor-driving gene transcription. We show that the MYB and ELF3 genes exhibit elevated transcript expression levels in mouse and human myometrial tissues during spontaneous term labor. The expression of both genes was also significantly increased in mouse myometrium during preterm labor induced by the progesterone antagonist mifepristone (RU486), but not during infection-simulating preterm labor induced by intrauterine infusion of lipopolysaccharide (LPS). Furthermore, both MYB and ELF3 proteins affect labor-driving gene promoter activity, although in surprisingly opposing ways: Gja1 and Fos promoter activation increases in the presence of MYB and decreases in the presence of ELF3. Collectively, our study adds to the current understanding of the transcription factor network that defines the transcriptomes of SMCs during late gestation and implicates two new players in the control of labor timing.

In vitro and ex vivo models for evaluating vaginal drug delivery systems

Vaginal drug delivery systems are often preferred for treating a variety of diseases and conditions of the female reproductive tract (FRT), as delivery can be more targeted with less systemic side effects. However, there are many anatomical and biological barriers to effective treatment via the vaginal route. Further, biocompatibility with the local tissue and microbial microenvironment is desired. A variety of in vitro and ex vivo models are described herein for evaluating the physicochemical properties and toxicity profile of vaginal drug delivery systems. Deciding whether to utilize organoids in vitro or fresh human cervicovaginal mucus ex vivo requires careful consideration of the intended use and the formulation characteristics. Optimally, in vitro and ex vivo experimentation will inform or predict in vivo performance, and examples are given that describe utilization of a range of methods from in vitro to in vivo. Lastly, we highlight more advanced model systems for other mucosa as inspiration for the future in model development for the FRT.

Progesterone and its receptor signaling in cervical remodeling: Mechanisms of physiological actions and therapeutic implications

The remodeling of the cervix from a closed rigid structure to one that can open sufficiently for passage of a term infant is achieved by a complex series of molecular events that in large part are regulated by the steroid hormones progesterone and estrogen. Among hormonal influences, progesterone exerts a dominant role for most of pregnancy to initiate a loss of tissue strength yet maintain competence in a phase termed softening. Equally important are the molecular events that abrogate progesterone function in late pregnancy to allow a loss of tissue competence and strength during cervical ripening and dilation. In this review, we focus on current understanding by which progesterone receptor signaling for the majority of pregnancy followed by a loss/shift in progesterone receptor action at the end of pregnancy, collectively ensure cervical remodeling as necessary for successful parturition.

N,N-Dimethylformamide Delays LPS-Induced Preterm Birth in a Murine Model by Suppressing the Inflammatory Response

Preterm birth accounts for the majority of perinatal mortality worldwide, and there remains no FDA-approved drug to prevent it. Recently, we discovered that the common drug excipient, N,N-dimethylacetamide (DMA), delays inflammation-induced preterm birth in mice by inhibiting NF-κB. Since we reported this finding, it has come to light that a group of widely used, structurally related aprotic solvents, including DMA, N-methyl-2-pyrrolidone (NMP) and dimethylformamide (DMF), have anti-inflammatory efficacy. We show here that DMF suppresses LPS-induced TNFα secretion from RAW 264.7 cells and IL-6 and IL-8 secretion from HTR-8 cells at concentrations that do not significantly affect cell viability. Like DMA, DMF protects IκBα from degradation and prevents the p65 subunit of NF-κB from translocating to the nucleus. In vivo, DMF decreases LPS-induced inflammatory cell infiltration and expression of TNFα and IL-6 in the placental labyrinth, all to near baseline levels. Finally, DMF decreases the rate of preterm birth in LPS-induced pregnant mice (P<.0001) and the rate at which pups are spontaneously aborted (P<.0001). In summary, DMF, a widely used solvent structurally related to DMA and NMP, delays LPS-induced preterm birth in a murine model without overt toxic effects. Re-purposing the DMA/DMF/NMP family of small molecules as anti-inflammatory drugs is a promising new approach to delaying or reducing the incidence of inflammation-induced preterm birth and potentially attenuating other inflammatory disorders as well.

Vaginal Nanoformulations for the Management of Preterm Birth

Preterm birth (PTB) is a leading cause of infant morbidity and mortality in the world. In 2020, 1 in 10 infants were born prematurely in the United States. The World Health Organization estimates that a total of 15 million infants are born prematurely every year. Current therapeutic interventions for PTB have had limited replicable success. Recent advancements in the field of nanomedicine have made it possible to utilize the vaginal administration route to effectively and locally deliver drugs to the female reproductive tract. Additionally, studies using murine models have provided important insights about the cervix as a gatekeeper for pregnancy and parturition. With these recent developments, the field of reproductive biology is on the cusp of a paradigm shift in the context of treating PTB. The present review focuses on the complexities associated with treating the condition and novel therapeutics that have produced promising results in preclinical studies.

MPTHub: An Open-Source Software for Characterizing the Transport of Particles in Biorelevant Media

The study of particle transport in different environments plays an essential role in understanding interactions with humans and other living organisms. Importantly, obtained data can be directly used for multiple applications in fields such as fundamental biology, toxicology, or medicine. Particle movement in biorelevant media can be readily monitored using microscopy and converted into time-resolved trajectories using freely available tracking software. However, translation into tangible and meaningful parameters is time consuming and not always intuitive. We developed new software—MPTHub—as an open-access, standalone, user-friendly tool for the rapid and reliable analysis of particle trajectories extracted from video microscopy. The software was programmed using Python and allowed to import and analyze trajectory data, as well as to export relevant data such as individual and ensemble time-averaged mean square displacements and effective diffusivity, and anomalous transport exponent. Data processing was reliable, fast (total processing time of less than 10 s), and required minimal memory resources (up to a maximum of around 150 MB in random access memory). Demonstration of software applicability was conducted by studying the transport of different polystyrene nanoparticles (100–200 nm) in mucus surrogates. Overall, MPTHub represents a freely available software tool that can be used even by inexperienced users for studying the transport of particles in biorelevant media.

Association of maternal obesity with preterm birth phenotype and mediation effects of gestational diabetes mellitus and preeclampsia: a prospective cohort study

BACKGROUND

The association between maternal obesity and preterm birth remains controversial and inconclusive, and the effects of gestational diabetes mellitus (GDM) and preeclampsia (PE) on the relationship between obesity and preterm birth have not been studied. We aimed to clarify the relationship between prepregnancy body mass index (BMI) and the phenotypes of preterm birth and evaluate the mediation effects of GDM and PE on the relationship between prepregnancy BMI and preterm birth.

METHODS

We conducted a prospective cohort study of 43,056 women with live singleton births from 2017 through 2019. According to the WHO International Classification, BMI was classified as underweight (BMI < 18.5 kg/m2), normal weight (BMI 18.5-25 kg/m2), overweight (BMI 25-30 kg/m2) and obese (BMI ≥30 kg/m2). Preterm birth was defined as gestational age less than 37 weeks (extremely, < 28 weeks; very, 28-31 weeks; and moderately, 32-36 weeks). The clinical phenotypes of preterm birth included spontaneous preterm birth (spontaneous preterm labor and premature rupture of the membranes) and medically indicated preterm birth. We further analyzed preterm births with GDM or PE. Multivariable logistic regression analysis and causal mediation analysis were performed.

RESULTS

Risks of extremely, very, and moderately preterm birth increased with BMI, and the highest risk was observed for obese women with extremely preterm birth (OR 3.43, 95% CI 1.07-10.97). Maternal obesity was significantly associated with spontaneous preterm labor (OR 1.98; 95% CI 1.13-3.47), premature rupture of the membranes (OR 2.04; 95% CI 1.08-3.86) and medically indicated preterm birth (OR 2.05; 95% CI 1.25-3.37). GDM and PE mediated 13.41 and 36.66% of the effect of obesity on preterm birth, respectively. GDM mediated 32.80% of the effect of obesity on spontaneous preterm labor and PE mediated 64.31% of the effect of obesity on medically indicated preterm birth.

CONCLUSIONS

Maternal prepregnancy obesity was associated with all phenotypes of preterm birth, and the highest risks were extremely preterm birth and medically indicated preterm birth. GDM and PE partially mediated the association between obesity and preterm birth.

Application of Sol–Gels for Treatment of Gynaecological Conditions—Physiological Perspectives and Emerging Concepts in Intravaginal Drug Delivery

Approaches for effective and sustained drug delivery to the female reproductive tract (FRT) for treating a range of gynaecological conditions remain limited. The development of versatile delivery platforms, such as soluble gels (sol–gels) coupled with applicators/devices, holds considerable therapeutic potential for gynaecological conditions. Sol–gel systems, which undergo solution-to-gel transition, triggered by physiological conditions such as changes in temperature, pH, or ion composition, offer advantages of both solution- and gel-based drug formulations. Furthermore, they have potential to be used as a suitable drug delivery vehicle for other novel drug formulations, including micro- and nano-particulate systems, enabling the delivery of drug molecules of diverse physicochemical character. We provide an anatomical and physiological perspective of the significant challenges and opportunities in attaining optimal drug delivery to the upper and lower FRT. Discussion then focuses on attributes of sol–gels that can vastly improve the treatment of gynaecological conditions. The review concludes by showcasing recent advances in vaginal formulation design, and proposes novel formulation strategies enabling the infusion of a wide range of therapeutics into sol–gels, paving the way for patient-friendly treatment regimens for acute and chronic FRT-related conditions such as bacterial/viral infection control (e.g., STDs), contraception, hormone replacement therapy (HRT), infertility, and cancer.

15-Deoxy-Delta-12,14-prostaglandin J2 modulates pro-labour and pro-inflammatory responses in human myocytes, vaginal and amnion epithelial cells

BACKGROUND

Prematurity is the leading cause of childhood death under the age of five. The aetiology of preterm birth is multifactorial; however, inflammation and infection are the most common causal factors, supporting a potential role for immunomodulation as a therapeutic strategy. 15-Deoxy-Delta-12,14-prostaglandin J2 (15dPGJ2) is an anti-inflammatory prostaglandin and has been shown to delay lipopolysaccharide (LPS) induced preterm labour in mice and improve pup survival. This study explores the immunomodulatory effect of 15dPGJ2 on the transcription factors NF-κB and AP-1, pro-inflammatory cytokines, and contraction associated proteins in human cultured myocytes, vaginal epithelial cell line (VECs) and primary amnion epithelial cells (AECs).

METHODS

Cells were pre-incubated with 32µM of 15dPGJ2 and stimulated with 1ng/mL of IL-1β as an in vitro model of inflammation. Western immunoblotting was used to detect phosphorylated p-65 and phosphorylated c-Jun as markers of NF-κB and AP-1 activation, respectively. mRNA expression of the pro-inflammatory cytokines IL-6, IL-8, and TNF-α was examined, and protein expression of COX-2 and PGE2 were detected by western immunoblotting and ELISA respectively. Myometrial contractility was examined ex-vivo using a myograph.

RESULTS

15dPGJ2 inhibited IL-1β-induced activation of NF-κB and AP-1, and expression of IL-6, IL-8, TNF-α, COX-2 and PGE2 in myocytes, with no effect on myometrial contractility or cell viability. Despite inhibiting IL-1β-induced activation of NF-κB, expression of IL-6, TNF-α, and COX-2, 15dPGJ2 led to activation of AP-1, increased production of PGE2 and increased cell death in VECs and AECs.

CONCLUSION

We conclude that 15dPGJ2 has differential effects on inflammatory modulation depending on cell type and is therefore unlikely to be a useful therapeutic agent for the prevention of preterm birth.

Bioconjugation of Active Ingredients to Plant Viral Nanoparticles Is Enhanced by Preincubation with a Pluronic F127 Polymer Scaffold

Proteinaceous nanoparticles can be used to deliver large payloads of active ingredients, which is advantageous in medicine and agriculture. However, the conjugation of hydrophobic ligands to hydrophilic nanocarriers such as plant viral nanoparticles (plant VNPs) can result in aggregation by reducing overall solubility. Given the benefits of hydrophilic nanocarrier platforms for targeted delivery and multivalent ligand display, coupled with the versatility of hydrophobic drugs, contrast agents, and peptides, this is an issue that must be addressed to realize their full potential. Here, we report two preincubation strategies that use a Pluronic F127 polymer scaffold to prevent the aggregation of conjugated plant VNPs: a plant VNP-polymer precoat (COAT) and an active ingredient formulation combined with a plant VNP-polymer precoat (FORMCOAT). The broad applications of these modified conjugation strategies were highlighted by testing their compatibility with three types of bioconjugation chemistry: N-hydroxysuccinimide ester-amine coupling, maleimide-thiol coupling, and copper(I)-catalyzed azide-alkyne cycloaddition (click chemistry). The COAT and FORMCOAT strategies promoted efficient bioconjugation and prevented the aggregation that accompanies conventional bioconjugation methods, thus improving the stability, homogeneity, and translational potential of plant VNP conjugates in medicine and agriculture.

Mucus-producing 3D cell culture models

In vitro cell-based models have been used for a long time since they are normally easily obtained and have an advantageous cost-benefit. Besides, they can serve a variety of ends, from studying drug absorption and metabolism to disease modeling. However, some in vitro models are too simplistic, not accurately representing the living tissues. It has been shown, mainly in the last years, that fully mimicking a tissue composition and architecture can be paramount for cellular behavior and, consequently, for the outcomes of the studies using such models. Because of this, 3D in vitro cell models have been gaining much attention, since they are able to better replicate the in vivo environment. In this review we focus on 3D models that contain mucus-producing cells, as mucus can play a pivotal role in drug absorption. Being frequently overlooked, this viscous fluid can have an impact on drug delivery. Thus, the aim of this review is to understand to which extent can mucus affect mucosal drug delivery and to provide a state-of-the-art report on the existing 3D cell-based mucus models.

Histone Deacetylase Inhibitors: Providing New Insights and Therapeutic Avenues for Unlocking Human Birth

The pregnant uterus remains relaxed throughout fetal gestation before transforming to a contractile phenotype at term to facilitate birth. Despite ongoing progress, the precise mechanisms that regulate this phenotypic transformation are not yet understood. This knowledge gap limits our understanding of how dysregulation of uterine smooth muscle biology contributes to life-threatening obstetric complications, including preterm birth, and hampers our ability to develop effective therapeutic intervention strategies. Protein acetylation plays a vital role in regulating protein structure, function, and subcellular localization, as well as gene transcription availability through regulating chromatin condensation. Histone deacetylase inhibitors (HDACis) are a class of compounds that block the removal of acetyl functional groups from proteins and, as such, have profound effects on important cellular events, including phenotypic transformation. A large body of data now demonstrates that HDACis have profound effects on pregnant human myometrium. Studies to date show that HDACis operate through both genomic and non-genomic mechanisms to affect myometrial function and phenotype. Interestingly, the effects of HDACis on pregnant myometrium are largely "pro-relaxation," including the direct inhibition of contractile machinery as well as repression of pro-labor genes. The "dual action" effects of HDACis make them a powerful tool for unlocking the regulatory processes that underpin myometrial phenotypic transformation and raises prospects of their therapeutic applications. Here, we review the new insights into human myometrial biology that have garnered through the application of HDACis and explore their potential therapeutic application toward the development of novel preterm birth prevention strategies.

Targeted drug delivery for maternal and perinatal health: Challenges and opportunities

Pre-existing conditions at reproductive age, and complications arising during pregnancy can be detrimental to maternal and fetal health. Current therapies to combat obstetric disorders are limited due to the inherent complexity of pregnancy, and can have harmful effects on developing fetus. Emerging research shows intricate signaling between the cells from mother and fetus at maternal-fetal interface, providing unique opportunities for interventions specifically targeted to the mother, fetus, or placenta. Advancements in nanotechnology, stem-cell biology and gene therapy have resulted in target-specific treatments with promising results in pre-clinical maternal and fetal disorder models. Comprehensive understanding of the effect of physicochemical properties of delivery systems on their uptake, retention and accumulation across placenta will help in the better diagnosis and treatment of perinatal disorders. This review describes the factors leading to obstetric complications along with their effect on pregnancy outcomes, and discusses key targeted therapeutic strategies for addressing conditions related to maternal and fetal health.

An ion-paired moxifloxacin nanosuspension eye drop provides improved prevention and treatment of ocular infection

There are numerous barriers to achieving effective intraocular drug administration, including the mucus layer protecting the ocular surface. For this reason, antibiotic eye drops must be used multiple times per day to prevent and treat ocular infections. Frequent eye drop use is inconvenient for patients, and lack of adherence to prescribed dosing regimens limits treatment efficacy and contributes to antibiotic resistance. Here, we describe an ion-pairing approach used to create an insoluble moxifloxacin-pamoate (MOX-PAM) complex for formulation into mucus-penetrating nanosuspension eye drops (MOX-PAM NS). The MOX-PAM NS provided a significant increase in ocular drug absorption, as measured by the area under the curve in cornea tissue and aqueous humor, compared to Vigamox in healthy rats. Prophylactic and treatment efficacy were evaluated in a rat model of ocular Staphylococcus aureus infection. A single drop of MOX-PAM NS was more effective than Vigamox, and completely prevented infection. Once a day dosing with MOX-PAM NS was similar, if not more effective, than three times a day dosing with Vigamox for treating S. aureus infection. The MOX-PAM NS provided increased intraocular antibiotic absorption and improved prevention and treatment of ocular keratitis, and the formulation approach is highly translational and clinically relevant.

Women-specific routes of administration for drugs: A critical overview

The woman's body presents a number of unique anatomical features that can constitute valuable routes for the administration of drugs, either for local or systemic action. These are associated with genitalia (vaginal, endocervical, intrauterine, intrafallopian and intraovarian routes), changes occurring during pregnancy (extra-amniotic, intra-amniotic and intraplacental routes) and the female breast (breast intraductal route). While the vaginal administration of drug products is common, other routes have limited clinical application and are fairly unknown even for scientists involved in drug delivery science. Understanding the possibilities and limitations of women-specific routes is of key importance for the development of new preventative, diagnostic and therapeutic strategies that will ultimately contribute to the advancement of women's health. This article provides an overview on women-specific routes for the administration of drugs, focusing on aspects such as biological features pertaining to drug delivery, relevance in current clinical practice, available drug dosage forms/delivery systems and administration techniques, as well as recent trends in the field.

The Preventive Effects of Quercetin on Preterm Birth Based on Network Pharmacology and Bioinformatics

Our previous study has shown that quercetin prevented lipopolysaccharide-induced preterm birth. This study aims to clarify the potential targets and biological mechanisms of quercetin in preventing preterm birth. We used bioinformatics databases to collect the candidate targets for quercetin and preterm birth. The biological functions and enriched pathways of the intersecting targets were analyzed by gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses. Then, the hub targets were identified by cytoscape plugin cytoHubba from the protein-protein interaction network. We obtained 105 targets for quercetin in preventing preterm birth. The biological processes of the intersecting targets are mainly involved in steroid metabolic process, drug metabolic process, oxidation-reduction process, omega-hydroxylase P450 pathway, positive regulation of cell migration, negative regulation of apoptotic process, and positive regulation of cell proliferation. The highly enriched pathways were steroid hormone biosynthesis, metabolism of xenobiotics by cytochrome P450, proteoglycans in cancer, focal adhesion, and arachidonic acid metabolism. The ten hub targets for quercetin in preventing preterm birth were AKT serine/threonine kinase 1, mitogen-activated protein kinase 3, epidermal growth factor receptor, prostaglandin-endoperoxide synthase 2, mitogen-activated protein kinase 1, estrogen receptor 1, heat shock protein 90 alpha family class A member 1, mitogen-activated protein kinase 8, androgen receptor, and matrix metallopeptidase 9. Molecular docking analysis showed good bindings between these proteins and quercetin. In conclusion, these findings highlight the key targets and molecular mechanisms of quercetin in preventing preterm birth.

Next generation strategies for preventing preterm birth

Preterm birth (PTB) is defined as delivery before 37 weeks of gestation. Globally, 15 million infants are born prematurely, putting these children at an increased risk of mortality and lifelong health challenges. Currently in the U.S., there is only one FDA approved therapy for the prevention of preterm birth. Makena is an intramuscular progestin injection given to women who have experienced a premature delivery in the past. Recently, however, Makena failed a confirmatory trial, resulting the Center for Drug Evaluation and Research's (CDER) recommendation for the FDA to withdrawal Makena's approval. This recommendation would leave clinicians with no therapeutic options for preventing PTB. Here, we outline recent interdisciplinary efforts involving physicians, pharmacologists, biologists, chemists, and engineers to understand risk factors associated with PTB, to define mechanisms that contribute to PTB, and to develop next generation therapies for preventing PTB. These advances have the potential to better identify women at risk for PTB, prevent the onset of premature labor, and, ultimately, save infant lives.

Landscape of Preterm Birth Therapeutics and a Path Forward

Preterm birth (PTB) remains the leading cause of infant morbidity and mortality. Despite 50 years of research, therapeutic options are limited and many lack clear efficacy. Tocolytic agents are drugs that briefly delay PTB, typically to allow antenatal corticosteroid administration for accelerating fetal lung maturity or to transfer patients to high-level care facilities. Globally, there is an unmet need for better tocolytic agents, particularly in low- and middle-income countries. Although most tocolytics, such as betamimetics and indomethacin, suppress downstream mediators of the parturition pathway, newer therapeutics are being designed to selectively target inflammatory checkpoints with the goal of providing broader and more effective tocolysis. However, the relatively small market for new PTB therapeutics and formidable regulatory hurdles have led to minimal pharmaceutical interest and a stagnant drug pipeline. In this review, we present the current landscape of PTB therapeutics, assessing the history of drug development, mechanisms of action, adverse effects, and the updated literature on drug efficacy. We also review the regulatory hurdles and other obstacles impairing novel tocolytic development. Ultimately, we present possible steps to expedite drug development and meet the growing need for effective preterm birth therapeutics.

Avoiding a Sticky Situation: Bypassing the Mucus Barrier for Improved Local Drug Delivery

The efficacy of drugs administered by traditional routes is limited by numerous biological barriers that preclude reaching the intended site of action. Further, full body systemic exposure leads to dose-limiting, off-target side effects. Topical formulations may provide more efficacious drug and nucleic acid delivery for diseases and conditions affecting mucosal tissues, but the mucus protecting our epithelial surfaces is a formidable barrier. Here, we describe recent advances in mucus-penetrating approaches for drug and nucleic acid delivery to the ocular surface, the female reproductive tract, the gastrointestinal tract, and the airways.