A revised two-stage model of preeclampsia is proposed, centering on an autophagy-dependent requirement for extravillous trophoblast entry into the proximal one-third of the myometrium. The One-Third Myometrium Enigma, introduced here, denotes the unresolved physiological rule that early placentation requires trophoblasts to traverse decidua and reach the proximal one-third of myometrium under hypoxia and nutrient scarcity. The hypothesis posits a timed rise in basal autophagy to sustain trophoblast energy homeostasis and invasion, accompanied by TFEB-driven lysosomal programs that enable villous cytotrophoblast syncytialization. Autophagic dysfunction could contribute to shallow invasion, chronic placental hypoxia, fetal growth restriction, and release of placental injury signals preceding maternal syndrome. Potential failure modes include reduced autophagic flux due to inhibition of autophagosome to lysosome fusion or mistimed persistence of hypoxia signaling, such as prolonged HIF-1α activity. Collectively, this evidence suggests that impaired autophagy is a testable contributor to preeclampsia pathogenesis. Predictions include early risk stratification with circulating autophagy markers and extracellular vesicle microRNAs, and therapeutic benefit from autophagy modulation that targets AMPK or mTOR or activates TFEB with safety constraints. This framework reframes preeclampsia as a disorder of placental quality control and specifies where and when autophagy may be required.

PROBLEM:Preeclampsia (PE) is a severe pregnancy disorder caused by a multitude of dysregulated events, including placental insufficiency, inflammation, anti-angiogenic factors, and cellular stress signals. Inflammatory activation of the complement cascade has also been thought to be a contributory factor to PE pathophysiology. However, the placental and circulating presence of activated complement factors and their precise impact on gestational age-dependent trophoblast health remain inadequately addressed. METHOD OF STUDY:Complement activation was assessed in placental tissue samples from women with normal pregnancy (NP) and PE. Immunofluorescent staining was employed to detect the membrane attack complex (MAC) deposition in placental tissues. This approach was also used in placenta-derived human extravillous trophoblast cells derived from the third trimester (TCL1) and first trimester (HTR-8) and term primary human cytotrophoblasts. Dual staining with Propidium Iodide (PI) and annexin V antibody was conducted to assess cell viability in TCL-1 cells, HTR-8 cells, and freshly isolated term primary human trophoblasts when exposed to serum samples from NP (NPS), PE (PES), and PES after complement inactivation by heating, heparin treatment, or blockade with antibodies. The expression levels of complement regulatory proteins, specifically decay-accelerating factor (CD55), protectin (CD59), and membrane cofactor protein (CD46), on trophoblasts were quantified using Fluorescence-activated cell sorting and immunohistochemistry. RESULTS:Substantial MAC deposition and a notable reduction in CD55 expression in the PE placenta compared to that from NP was observed, indicating heightened complement activation and impaired complement regulation in PE. Exposure to a significant subpopulation of PES (41%, n = 41) induced cell death exclusively in TCL-1 cells, not in HTR-8 cells and primary human trophoblasts. Remarkably, complement inactivation in PES abolished MAC deposition and rescued TCL-1 cells from death, unequivocally implicating complement activity in trophoblast cell demise. Flow cytometry analysis disclosed lower levels of CD55 and CD59 expression in TCL-1 cells in contrast to HTR-8 cells and primary human trophoblasts. Blockade of CD55 and CD59 in HTR-8 cells enhanced their susceptibility to PES-induced cell death. CONCLUSIONS:These findings underscore the significance of amplified complement activation, compromised complement inhibitory regulation, and consequent trophoblast cell death as potential contributors to the pathogenesis of PE. Strategies targeting dysregulated complement activity offer promising avenues for novel therapeutic interventions in PE management.

SARS-CoV-2 infection during pregnancy is associated with an increased risk of pre-eclampsia (PE), a hypertensive disorder, but the molecular mechanisms remain poorly understood. Here, we identify ORF3a, a SARS-CoV-2 accessory protein, as a key factor in placental dysfunction, driving autophagy dysregulation, trophoblast maturation impairment, protein aggregation and placental barrier disruption-processes linked to PE. We detect ORF3a in placentas from women infected with SARS-CoV-2 along with increased protein aggregation and disrupted tight junctions in ORF3a + regions. In placental cell lines, ORF3a impairs syncytiotrophoblast maturation and induces protein aggregation. Mechanistically, ORF3a binds to ZO-1 via its PDZ-binding motif (SVPL), and deletion of this domain from ORF3a abrogates its effect on trophoblast barrier integrity. In human trophoblast cells engineered with an LC3-GFP-mCherry reporter, ORF3a induces autophagosome accumulation, and shifts autophagy toward a secretory pathway with elevated levels of CD63 + extracellular vesicles and disrupted ZO-1 localization, all of which are recapitulated by live infection with the SARS-CoV-2 Delta variant. These ORF3a-dependent changes are fully recapitulated in 3D stem-cell-derived trophoblast organoids (SC-TOs). Together, our findings define a molecular mechanism by which SARS-CoV-2 infection compromises placental syncytial integrity. Targeting ORF3a may provide a therapeutic strategy to mitigate PE-like placental dysfunction in SARS-CoV-2-infected pregnancies.

In recent years, targeted protein degradation (TPD) strategies leveraging the autophagy-lysosomal pathway (ALP) have transcended the limitations of conventional drug molecules, emerging as a highly promising approach for selectively eliminating disease-related proteins via the cell's intrinsic degradation machinery. These TPD methods, such as autophagosome-tethering compounds (ATTEC), autophagy-targeting chimera (AUTAC), AUTOphagy-TArgeting chimera (AUTOTAC), and chaperone-mediated autophagy (CMA) targeting chimera, exhibit efficacy in degrading misfolded protein aggregates associated with neurodegenerative disorders. Moreover, the excessive accumulation of misfolded proteins or protein complexes in the placenta has been identified as a significant contributor to preeclampsia (PE). Given the lack of effective treatments for PE, the application of autophagy-mediated TPD technology presents a novel therapeutic avenue. This review draws parallels between misfolded protein aggregates in neurodegenerative diseases and placenta-derived PE, integrating a substantial number of full-text studies. By harnessing TPD technologies grounded in the ALP, these autophagic degraders offer a pioneering approach for targeted therapy in PE by dismantling potential targets. Presently, there is limited exploration of ALP technology for identifying target proteins in the placenta. Nonetheless, we have proposed several potential target proteins, laying the groundwork for future therapeutic endeavors.

Bacterial vaginosis (BV) is the most commonly diagnosed vaginal infection in women of reproductive age, with most patients unaware that they have BV due to its asymptomatic nature. BV is a dysbiotic condition defined by a deviation from the healthy Lactobacillus dominance to a polymicrobial anaerobic bacterial community that increases the risk of sexually transmitted infections and adverse reproductive outcomes, including spontaneous preterm birth. The increasing number of infectious agents in BV, biofilm persistence and antibiotic resistance in the vaginal canal hinder effective treatments with antibiotics leading to consistent recurrence of BV in many women (30–70

Preeclampsia (preE) is a severe multisystem hypertensive syndrome of pregnancy associated with ischemia/hypoxia, angiogenic imbalance, apolipoprotein E (ApoE)-mediated dyslipidemia, placental insufficiency, and inflammation at the maternal–fetal interface. Our recent data further suggest that preE is associated with impaired autophagy, vascular dysfunction, and proteinopathy/tauopathy disorder, similar to neurodegenerative diseases such as Alzheimer’s disease (AD), including the presence of the cis stereo-isoform of phosphorylated tau (cis P-tau), amyloid-β, and transthyretin in the placenta and circulation. This review provides an overview of the factors that may lead to the induction and accumulation of cis P-tau-like proteins by focusing on the inactivation of peptidyl-prolyl cis–trans isomerase (Pin1) that catalyzes the cis to trans isomerization of P-tau. We also highlighted the novel role of the Pin1-cis P-tau-ApoE axis in the development of preE, and propagation of cis P-tau-mediated abnormal protein aggregation (tauopathy) from the placenta to cerebral tissues later in life, leading to neurodegenerative conditions. In the case of preE, proteinopathy/tauopathy may interrupt trophoblast differentiation and induce cell death, similar to the events occurring in neurons. These events may eventually damage the endothelium and cause systemic features of disorders such as preE. Despite impressive research and therapeutic advances in both fields of preE and neurodegenerative diseases, further investigation of Pin1-cis P-tau and ApoE-related mechanistic underpinnings may unravel novel therapeutic options, and new transcriptional and proteomic markers. This review will also cover genetic polymorphisms in the ApoE alleles leading to dyslipidemia induction that may regulate the pathways causing preE or dementia-like features in the reproductive age or later in life, respectively.

SARS-CoV-2 infection poses a significant risk to placental physiology, but its impact on placental homeostasis is not well understood. We and others have previously shown that SARS-CoV-2 can colonize maternal and fetal placental cells, yet the specific mechanisms remain unclear. In this study, we investigate ORF3a, a key accessory protein of SARS-CoV-2 that exhibits continuous mutations. Our findings reveal that ORF3a is present in placental tissue from pregnant women infected with SARS-CoV-2 and disrupts autophagic flux in placental cell lines and 3D stem-cell-derived trophoblast organoids (SCTOs), impairing syncytiotrophoblast differentiation and trophoblast invasion. This disruption leads to protein aggregation in cytotrophoblasts (CTB) and activates secretory autophagy, increasing CD63+ extracellular vesicle secretion, along with ORF3a itself. ORF3a also compromises CTB barrier integrity by disrupting tight junctions via interaction with ZO-1, mediated by its PDZ-binding motif, SVPL. Colocalization of ORF3a and ZO-1 in SARS-CoV-2-infected human placental tissue supports our in vitro findings. Deleting the PDZ binding motif in the ORF3a protein (ORF3a-noPBM mutant) restored proper ZO-1 localization at the cell junctions in an autophagy-independent manner. Lastly, we demonstrate that constitutive ORF3a expression induces SC-TOs to transition towards a secretory autophagy pathway likely via the PBM motif, as the ORF3a-NoPBM mutants showed a significant lack of CD63 expression. This study demonstrates the functional impact of ORF3a on placental autophagy and reveals a new mechanism for the activation of secretory autophagy, which may lead to increased extracellular vesicle secretion. These findings provide a foundation for exploring therapeutic approaches targeting ORF3a, specifically focusing on its PBM region to block its interactions with host cellular proteins and limiting placental impact.

SARS-CoV-2 infection during pregnancy has severe consequences on maternal and neonatal health. Presently, vaccination stands as a critical preventive measure for mitigating infection-related risks. Although the initial clinical trials for the COVID-19 vaccines excluded pregnant women, subsequent investigations have indicated mRNA vaccinations' effectiveness and short-term safety during pregnancy. However, there is a lack of information regarding the potential biodistribution of the vaccine mRNA during pregnancy and lactation. Recent findings indicate that COVID-19 vaccine mRNA has been detected in breast milk, suggesting that its presence is not confined to the injection site and raises the possibility of similar distribution to the placenta and the fetus. Furthermore, the potential effects and responses of the placenta and fetus to the vaccine mRNA are still unknown. While potential risks might exist with the exposure of the placenta and fetus to the COVID-19 mRNA vaccine, the application of mRNA therapies for maternal and fetal conditions offers a groundbreaking prospect. Future research should leverage the unique opportunity provided by the first-ever application of mRNA vaccines in humans to understand their biodistribution and impact on the placenta and fetus in pregnant women. Such insights could substantially advance the development of safer and more effective future mRNA-based therapies during pregnancy.

BACKGROUND:Maternal-fetal immunology is intricate, and the effects of mRNA-S maternal vaccination on immune regulation at the maternal-fetal interface require further investigation. Our study endeavors to elucidate these immunological changes, enhancing our comprehension of maternal and fetal health outcomes. By analyzing immune profiles and cytokine responses, we aim to provide valuable insights into the impact of mRNA-S vaccination on the delicate balance of immune regulation during pregnancy, addressing critical questions in the field of reproductive pharmacology. OBJECTIVES:This investigation sought to examine the prospective influence of mRNA-S-based vaccines and extracellular vesicles (EVs) containing the Spike (S) protein at the maternal-fetal interface. Our primary emphasis was on evaluating their effects on maternal decidua cells and fetal chorion trophoblast cells (hFM-CTCs). METHODS:We validated the generation of EVs containing the S protein from small human airway epithelial cell lines (HSAECs) following mRNA-S vaccine exposure. We assessed the expression of angiotensin-converting enzyme 2 (ACE2) gene and protein in fetal membranes and the placenta, with specific attention to decidual cells and fetal membrane chorion cells. To assess cellular functionality, these cells were exposed to both recombinant S protein and EVs loaded with S proteins (eSPs). RESULTS:Our findings revealed that cells and EVs subjected to mRNA-S-based vaccination exhibited altered protein expression levels of S proteins. At the feto-maternal interface, both placental and fetal membrane tissues demonstrated similar ACE-2 expression levels. Among individual cellular layers, syncytiotrophoblast cells in the placenta and chorion cells in the fetal membrane exhibited elevated ACE-2 expression. Notably, EVs derived from HSAECs activated the MAPK pathway in decidual cells. Additionally, decidual cells displayed a substantial increase in gene expression of chemokines like CXCL-10 and CXCL-11, as well as proinflammatory cytokines such as IL-6 in response to eSPs. However, the levels of Ccl-2 and IL-1β remained unchanged in decidual cells under the same conditions. Conversely, hFM-CTCs demonstrated significant alterations in the proinflammatory cytokines and chemokines with respect to eSPs. CONCLUSION:In conclusion, our study indicates that mRNA-S-based maternal vaccination during pregnancy may influence the maternal-fetal interface's COVID-19 interaction and immune regulation. Further investigation is warranted to assess safety and implications.

The etiology of preeclampsia (PE), a severe complication of pregnancy with several clinical manifestations and a high incidence of maternal and fetal morbidity and mortality, remains unclear. This issue is a major hurdle for effective treatment strategies. We recently demonstrated that PE exhibits an Alzheimer-like etiology of impaired autophagy and proteinopathy in the placenta. Targeting of these pathological pathways may be a novel therapeutic strategy for PE. Stimulation of autophagy with the natural disaccharide trehalose and its lacto analog lactotrehalose in hypoxia-exposed primary human trophoblasts restored autophagy, inhibited the accumulation of toxic protein aggregates, and restored the ultrastructural features of autophagosomes and autolysosomes. Importantly, trehalose and lactotrehalose inhibited the onset of PE-like features in a humanized mouse model by normalizing autophagy and inhibiting protein aggregation in the placenta. These disaccharides restored the autophagy-lysosomal biogenesis machinery by increasing nuclear translocation of the master transcriptional regulator TFEB. RNA-seq analysis of the placentas of mice with PE indicated the normalization of the PE-associated transcriptome profile in response to trehalose and lactotrehalose. In summary, our results provide a novel molecular rationale for impaired autophagy and proteinopathy in patients with PE and identify treatment with trehalose and its lacto analog as promising therapeutic options for this severe pregnancy complication. Autophagy, a process in cells that helps maintain organ growth and balance, is important for the immune system and stress response. However, when autophagy doesn't work properly, it can lead to diseases, including preeclampsia, a serious pregnancy issue. Dr. Surendra Sharma and his team at the Women and Infants Hospital of Rhode Island discovered that trehalose, a natural sugar, can fix autophagy and restore the ability of the cell's waste disposal system. They tested this on human cells and a mouse model of preeclampsia. The results showed that trehalose and a similar sugar, lactotrehalose, effectively fixed autophagy, stopped harmful protein buildup, and reduced the production of harmful factors associated with preeclampsia. This suggests that sugars like trehalose could be potential treatments for preeclampsia. "This summary was initially drafted using artificial intelligence, then revised and fact-checked by the author."

Preeclampsia (PE) is a leading cause of maternal and fetal morbidity and mortality and complicates 3-8% of all pregnancies. PE has been linked to high incidence of chronic diseases later in life, including cardiovascular disease, diabetes mellitus, and renal disease. Thus, directed therapy is critically important to improve both maternal and neonatal outcomes. However, to date, no effective therapy for this syndrome is clinically available. The most effective treatment is delivery of the placenta. Our recent novel findings suggest that PE and Alzheimer's disease (AD) share a common etiology of proteinopathy and impaired autophagy and that accumulation of protein aggregates in the PE placenta directly results from dysregulated lysosomal biogenesis. Our work also suggests that impaired autophagy not only enhances protein aggregate accumulation but also induces sterile inflammation and reduces endovascular ability of trophoblasts. This work has led to search for therapeutic interventions that uniquely target impaired autophagy and toxic protein aggregation. Our results suggest that restoration of autophagy and inhibition of protein aggregation in a humanized mouse model of PE as well as in hypoxia-exposed primary human trophoblasts support the hypothesis that impaired autophagy and proteinopathy can be successfully targeted to provide possible therapeutic options for treatment of PE. We propose to expand on these intriguing results and propose novel experiments to assess the efficacy of autophagy promoter small molecules to examine whether they can reverse transcriptome-wide changes and inflammation associated with PE in in vivo and in vitro models.

Inhibition of autophagy contributes to the pathophysiology of preeclampsia. Although chloroquine (CHQ) is an autophagy inhibitor, it can reduce the occurrence of preeclampsia in women with systemic lupus erythematosus. To clarify this important clinical question, this study aimed to address the safety of CHQ in trophoblast cells from the viewpoint of homeostasis, in which the anti-oxidative stress (OS) response and autophagy are involved. We used Western blotting to evaluate the protein levels in the trophoblast cells. The expression levels of heme oxygenase-1 (HO-1), an anti-OS enzyme, mediate resistance to OS induced by hydrogen peroxide (H2O2) in trophoblast cell lines. Among the autophagy modulators, bafilomycin A1 (BAF), an autophagy inhibitor, but not autophagy activators, suppressed HO-1 expression in BeWo cells; CHQ did not suppress HO-1 expression in BeWo cells. To clarify the role of autophagy in HO-1 induction, we observed no difference in HO-1 induction by H2O2 between autophagy-normal and autophagy-deficient cells. As for the mechanism of HO-1 induction by OS, BAF suppressed HO-1 induction by downregulating the expression of neighbor of BRCA1 gene 1 (NBR1) in the selective p62-NBR1-nuclear factor erythroid 2-related factor 2 (Nrf2) autophagy pathway. CHQ did not inhibit HO-1 expression by sustaining NBR1 expression in human villous tissues compared to BAF treatment. In conclusion, CHQ is a safer medicine than BAF for sustaining NBR1, which resist against OS in trophoblasts by connecting selective autophagy and the anti-OS response.

Autophagy is a fundamental process involved in regulating cellular homeostasis. Autophagy has been classically discovered as a cellular process that degrades cytoplasmic components non-selectively to produce energy. Over the past few decades, this process has been shown to work in energy production, as well as in the reduction of excessive proteins, damaged organelles, and membrane trafficking. It contributes to many human diseases, such as neurodegenerative diseases, carcinogenesis, diabetes mellitus, development, longevity, and reproduction. In this review, we provide important information for interpreting results related to autophagic experiments and present the role of autophagy in this field.

Autophagy is a lysosomal degradation pathway that supports metabolic adaptation and energy cycling. It is essential for cell homeostasis, differentiation, development, and survival. Recent studies have shown that autophagy could influence immune responses by regulating immune cell functions. Reciprocally, immune cells strongly influence autophagy. Immune cells at the maternal-fetal interface are thought to play essential roles in pregnancy. Here, we review the induction of autophagy at the maternal-fetal interface and its role in decidualization and placental development. Additionally, we emphasize the role of autophagy in the immune microenvironment at the maternal-fetal interface, including innate immunity, adaptive immunity, and immune tolerance molecules. It also suggests new research directions and prospects.

Abnormal trophoblast function is associated with diseases such as recurrent spontaneous abortion, pre-eclampsia, and preterm birth, and endangers maternal and fetal health. However, the underlying regulatory mechanisms remain unclear. In this study, we found DOCK1 expression is decreased in the placental villi of patients with recurrent spontaneous abortion, and that its expression determined the invasive properties of extravillous trophoblasts (EVTs), highlighting a previously unknown role of DOCK1 in regulating EVT function. Furthermore, DOCK1 deficiency disturbed the ubiquitinated degradation of DUSP4, leading to its accumulation. This caused inactivation of the ERK signaling pathway, resulting in inadequate EVT migration and invasion. DOCK1 was implicated in regulating the ubiquitin levels of DUSP4, possibly by modulating the E3 ligase enzyme HUWE1. The results of our in vivo experiments confirmed that the DOCK1 inhibitor TBOPP caused miscarriage in mice by inactivating the DUSP4/ERK pathway. Collectively, our results revealed the crucial role of DOCK1 in the regulation of EVT function via the DUSP4-ERK pathway and a basis for the development of novel treatments for adverse pregnancy outcomes caused by trophoblast dysfunction.

Our prior studies have shown that protein misfolding and aggregation in the placenta are linked to the development of preeclampsia, a severe pregnancy complication. We identified transthyretin (TTR) as a key component of the aggregated protein complex. However, the regulation of native TTR in normal pregnancy remains unclear. In this study, we found that pregnant mice exhibited a remarkable and progressive decline in serum TTR levels through gestational day (gd) 12-14, followed by an increase in late pregnancy and postpartum. Meanwhile, serum albumin levels showed a modest but statistically significant increase throughout gestation. TTR protein and mRNA levels in the liver, a primary source of circulating TTR, mirrored the changes observed in serum TTR levels during gestation. Intriguingly, a similar pattern of TTR alteration was also observed in the serum of pregnant women and pregnant interleukin-10-knockout (IL-10-/-) mice with high inflammation background. In non-pregnant IL-10-/- mice, serum TTR levels were significantly lower than those in age-matched wild-type mice. Administration of IL-10 to non-pregnant IL-10-/- mice restored their serum TTR levels. Notably, dysregulation of TTR resulted in fewer implantation units, lower fetal weight, and smaller litter sizes in human TTR-overexpressing transgenic mice. Thus, TTR may play a pivotal role as a crucial regulator in normal pregnancy, and inflammation during pregnancy may contribute to the downregulation of serum TTR presence.