Activation of a TLR9 mediated innate immune response in preeclampsia

Placental mitochondrial impairment and its association with maternal metabolic dysfunction

The placenta plays an essential role in pregnancy, leading to proper fetal development and growth. As an organ with multiple physiological functions for both mother and fetus, it is a highly energetic and metabolically demanding tissue. Mitochondrial physiology plays a crucial role in the metabolism of this organ and thus any alteration leading to mitochondrial dysfunction has a severe outcome in the development of the fetus. Pregnancy-related pathological states with a mitochondrial dysfunction outcome include preeclampsia and gestational diabetes mellitus. In this review, we address the role of mitochondrial morphology, metabolism and physiology of the placenta during pregnancy, highlighting the roles of the cytotrophoblast and syncytiotrophoblast. We also describe the relationship between preeclampsia, gestational diabetes, gestational diabesity and pre-pregnancy maternal obesity with mitochondrial dysfunction.

An integral role of mitochondrial function in the pathophysiology of preeclampsia

Preeclampsia (PE) is associated with high maternal and perinatal morbidity and mortality. The development of effective treatment strategies remains a major challenge due to the limited understanding of the pathogenesis. In this review, we summarize the current understanding of PE research, focusing on the molecular basis of mitochondrial function in normal and PE placentas, and discuss perspectives on future research directions. Mitochondria integrate numerous physiological processes such as energy production, cellular redox homeostasis, mitochondrial dynamics, and mitophagy, a selective autophagic clearance of damaged or dysfunctional mitochondria. Normal placental mitochondria have evolved innovative survival strategies to cope with uncertain environments (e.g., hypoxia and nutrient starvation). Cytotrophoblasts, extravillous trophoblast cells, and syncytiotrophoblasts all have distinct mitochondrial morphology and function. Recent advances in molecular studies on the spatial and temporal changes in normal mitochondrial function are providing valuable insight into PE pathogenesis. In PE placentas, hypoxia-mediated mitochondrial fission may induce activation of mitophagy machinery, leading to increased mitochondrial fragmentation and placental tissue damage over time. Repair mechanisms in mitochondrial function restore placental function, but disruption of compensatory mechanisms can induce apoptotic death of trophoblast cells. Additionally, molecular markers associated with repair or compensatory mechanisms that may influence the development and progression of PE are beginning to be identified. However, contradictory results have been obtained regarding some of the molecules that control mitochondrial biogenesis, dynamics, and mitophagy in PE placentas. In conclusion, understanding how the mitochondrial morphology and function influence cell fate decisions of trophoblast cells is an important issue in normal as well as pathological placentation biology. Research focusing on mitochondrial function will become increasingly important for elucidating the pathogenesis and effective treatment strategies of PE.

Circulating cell-free DNA and its association with cardiovascular disease: what we know and future perspectives

PURPOSE OF REVIEW

The aim of this review is to explore a possible link between cell-free DNA (cfDNA) and cardiovascular disease (CVD), which may hold valuable potential for future diagnostics.

RECENT FINDINGS

cfDNA has become topic of high interest across several medical fields. cfDNA is used as a diagnostic biomarker in cancer, prenatal care, and transplantation. In addition, cfDNA may play an unrecognized role in biological processes that are involved in or underlying various disease states, for example, inflammation. Elevated levels of cfDNA are associated with various elements of CVD, cardio-metabolic risk factors, and autoimmune diseases. Mitochondrial cfDNA and neutrophil extracellular traps may play distinct roles. Total circulating cfDNA may reflect the unspecific accumulation of stressors and the organism's susceptibility and resilience to such stressors. As such, cfDNA, in a stressful situation, may provide predictive value for future development of CVD. We suggest exploring such possibility through a large-scale prospective cohort study of pregnant women.

SUMMARY

There is no doubt that cfDNA is a valuable biomarker. For CVD, its potential is indicated but less explored. New studies may identify cfDNA as a valuable circulating cardiovascular risk marker to help improve risk stratification.

L-ergothioneine reduces mitochondrial-driven NLRP3 activation in gestational diabetes mellitus

BACKGROUND

Maternal hyperglycaemia has a significant impact on placental metabolism and mitochondrial function. The NLRP3 inflammasome is responsive to endogenous signals of mitochondrial dysfunction. We tested our hypothesis that mitochondrial dysfunction orchestrates activation of the NLRP3 inflammasome and contributes to inflammation in gestational diabetes mellitus (GDM).

METHODS

Fasting blood, omental and placental tissue were collected on the day of caesarean section from nulliparous women with normal glucose tolerant (NGT) (n = 30) and GDM (n = 27) pregnancies. Cell-free mitochondrial DNA (cf-mtDNA) copy number was quantified by real-time PCR. M1-like (CD14+CD86+CD206-) and M2-like (CD14+CD86+CD206+) macrophage populations were characterized by flow cytometry. Immunoblotting for protein expression of NLRP3, ASC and caspase-1 was performed in maternal BMI and age-matched tissue samples. IL-1β and IL-18 were measured by multiplex ELISA. Placental explants from GDM participants were cultured for 24 h with 1 mM L-ergothioneine (antioxidant) and 1 µM MCC950 (NLRP3 inhibitor).

RESULTS

Cf-mtDNA copy numbers were significantly higher in GDM compared to NGT participants (p = 0.002). Placental populations of CD14+ (p = 0.02) and CD14+CD86+CD206- (p = 0.03) macrophages produced significantly increased levels of mitochondrial superoxide in GDM compared to NGT participants. Placental production of IL-18 (p = 0.04) was significantly increased in GDM. This increase in placental IL-18 was attenuated by treatment with 1 µM MCC950 (p = 0.0005), and 1 mM L-ergothioneine (p = 0.007).

CONCLUSION

Placental inflammation is significantly increased in women with GDM. Furthermore, this increase may be initiated by elevated production of mitochondrial superoxide by macrophage subpopulations and orchestrated by the NLRP3 inflammasome. The mitochondrial antioxidant, L-ergothioneine, ameliorates NLRP3-induced placental inflammation in GDM, identifying a potential therapeutic role.

Identification and verification of diagnostic biomarkers based on mitochondria-related genes related to immune microenvironment for preeclampsia using machine learning algorithms

Preeclampsia is one of the leading causes of maternal and fetal morbidity and mortality worldwide. Preeclampsia is linked to mitochondrial dysfunction as a contributing factor in its progression. This study aimed to develop a novel diagnostic model based on mitochondria-related genes(MRGs) for preeclampsia using machine learning and further investigate the association of the MRGs and immune infiltration landscape in preeclampsia. In this research, we analyzed GSE75010 database and screened 552 DE-MRGs between preeclampsia samples and normal samples. Enrichment assays indicated that 552 DE-MRGs were mainly related to energy metabolism pathway and several different diseases. Then, we performed LASSO and SVM-RFE and identified three critical diagnostic genes for preeclampsia, including CPOX, DEGS1 and SH3BP5. In addition, we developed a novel diagnostic model using the above three genes and its diagnostic value was confirmed in GSE44711, GSE75010 datasets and our cohorts. Importantly, the results of RT-PCR confirmed the expressions of CPOX, DEGS1 and SH3BP5 were distinctly increased in preeclampsia samples compared with normal samples. The results of the CIBERSORT algorithm revealed a striking dissimilarity between the immune cells found in preeclampsia samples and those found in normal samples. In addition, we found that the levels of SH3BP5 were closely associated with several immune cells, highlighting its potential involved in immune microenvironment of preeclampsia. Overall, this study has provided a novel diagnostic model and diagnostic genes for preeclampsia while also revealing the association between MRGs and immune infiltration. These findings offer valuable insights for further research and treatment of preeclampsia.

Mitochondrial might: powering the peripartum for risk and resilience

The peripartum period, characterized by dynamic hormonal shifts and physiological adaptations, has been recognized as a potentially vulnerable period for the development of mood disorders such as postpartum depression (PPD). Stress is a well-established risk factor for developing PPD and is known to modulate mitochondrial function. While primarily known for their role in energy production, mitochondria also influence processes such as stress regulation, steroid hormone synthesis, glucocorticoid response, GABA metabolism, and immune modulation - all of which are crucial for healthy pregnancy and relevant to PPD pathology. While mitochondrial function has been implicated in other psychiatric illnesses, its role in peripartum stress and mental health remains largely unexplored, especially in relation to the brain. In this review, we first provide an overview of mitochondrial involvement in processes implicated in peripartum mood disorders, underscoring their potential role in mediating pathology. We then discuss clinical and preclinical studies of mitochondria in the context of peripartum stress and mental health, emphasizing the need for better understanding of this relationship. Finally, we propose mitochondria as biological mediators of resilience to peripartum mood disorders.

The Gut Microbiota of Pregnant Rats Alleviates Fetal Growth Restriction by Inhibiting the TLR9/MyD88 Pathway

Fetal growth restriction (FGR) is a prevalent obstetric condition. This study aimed to investigate the role of Toll-like receptor 9 (TLR9) in regulating the inflammatory response and gut microbiota structure in FGR. An FGR animal model was established in rats, and ODN1668 and hydroxychloroquine (HCQ) were administered. Changes in gut microbiota structure were assessed using 16S rRNA sequencing, and fecal microbiota transplantation (FMT) was conducted. HTR-8/Svneo cells were treated with ODN1668 and HCQ to evaluate cell growth. Histopathological analysis was performed, and relative factor levels were measured. The results showed that FGR rats exhibited elevated levels of TLR9 and myeloid differentiating primary response gene 88 (MyD88). In vitro experiments demonstrated that TLR9 inhibited trophoblast cell proliferation and invasion. TLR9 upregulated lipopolysaccharide (LPS), LPS-binding protein (LBP), interleukin (IL)-1β and tumor necrosis factor (TNF)-α while downregulating IL-10. TLR9 activated the TARF3-TBK1-IRF3 signaling pathway. In vivo experiments showed HCQ reduced inflammation in FGR rats, and the relative cytokine expression followed a similar trend to that observed in vitro. TLR9 stimulated neutrophil activation. HCQ in FGR rats resulted in changes in the abundance of Eubacterium_coprostanoligenes_group at the family level and the abundance of Eubacterium_coprostanoligenes_group and Bacteroides at the genus level. TLR9 and associated inflammatory factors were correlated with Bacteroides, Prevotella, Streptococcus, and Prevotellaceae_Ga6A1_group. FMT from FGR rats interfered with the therapeutic effects of HCQ. In conclusion, our findings suggest that TLR9 regulates the inflammatory response and gut microbiota structure in FGR, providing new insights into the pathogenesis of FGR and suggesting potential therapeutic interventions.

Differential immunophenotype of circulating monocytes from pregnant women in response to viral ligands

BACKGROUND

Viral infections during pregnancy can have deleterious effects on mothers and their offspring. Monocytes participate in the maternal host defense against invading viruses; however, whether pregnancy alters monocyte responses is still under investigation. Herein, we undertook a comprehensive in vitro study of peripheral monocytes to characterize the differences in phenotype and interferon release driven by viral ligands between pregnant and non-pregnant women.

METHODS

Peripheral blood was collected from third-trimester pregnant (n = 20) or non-pregnant (n = 20, controls) women. Peripheral blood mononuclear cells were isolated and exposed to R848 (TLR7/TLR8 agonist), Gardiquimod (TLR7 agonist), Poly(I:C) (HMW) VacciGrade™ (TLR3 agonist), Poly(I:C) (HMW) LyoVec™ (RIG-I/MDA-5 agonist), or ODN2216 (TLR9 agonist) for 24 h. Cells and supernatants were collected for monocyte phenotyping and immunoassays to detect specific interferons, respectively.

RESULTS

The proportions of classical (CD14^hiCD16^-), intermediate (CD14^hiCD16⁺), non-classical (CD14^loCD16⁺), and CD14^loCD16^- monocytes were differentially affected between pregnant and non-pregnant women in response to TLR3 stimulation. The proportions of pregnancy-derived monocytes expressing adhesion molecules (Basigin and PSGL-1) or the chemokine receptors CCR5 and CCR2 were diminished in response to TLR7/TLR8 stimulation, while the proportions of CCR5^- monocytes were increased. Such differences were found to be primarily driven by TLR8 signaling, rather than TLR7. Moreover, the proportions of monocytes expressing the chemokine receptor CXCR1 were increased during pregnancy in response to poly(I:C) stimulation through TLR3, but not RIG-I/MDA-5. By contrast, pregnancy-specific changes in the monocyte response to TLR9 stimulation were not observed. Notably, the soluble interferon response to viral stimulation by mononuclear cells was not diminished in pregnancy.

CONCLUSIONS

Our data provide insight into the differential responsiveness of pregnancy-derived monocytes to ssRNA and dsRNA, mainly driven by TLR8 and membrane-bound TLR3, which may help to explain the increased susceptibility of pregnant women to adverse outcomes resulting from viral infection as observed during recent and historic pandemics.

Gestational exposure to unmethylated CpG oligonucleotides dysregulates placental molecular clock network and fetoplacental growth dynamics, and disrupts maternal blood pressure circadian rhythms in rats

Bacterial infections and impaired mitochondrial DNA dynamics are associated with adverse pregnancy outcomes. Unmethylated cytosine-guanine dinucleotide (CpG) motifs are common in bacterial and mitochondrial DNA and act as potent immunostimulators. Here, we tested the hypothesis that exposure to CpG oligonucleotides (ODN) during pregnancy would disrupt blood pressure circadian rhythms and the placental molecular clock machinery, mediating aberrant fetoplacental growth dynamics. Rats were repeatedly treated with CpG ODN in the 3 ^rd trimester (gestational day, GD, 14, 16, 18) and euthanized on GD20 (near term) or with a single dose of CpG ODN and euthanized 4 hours after treatment on GD14. Hemodynamic circadian rhythms were analyzed via Lomb-Scargle periodogram analysis on 24-h raw data collected continuously via radiotelemetry. A p -value ≥ 0.05 indicates the absence of a circadian rhythm. Following the first treatment with CpG ODN, maternal systolic and diastolic blood pressure circadian rhythms were lost ( p ≥ 0.05). Blood pressure circadian rhythm was restored by GD16 and remained unaffected after the second treatment with CpG ODN ( p < 0.0001). Diastolic blood pressure circadian rhythm was again lost after the last treatment on GD18 ( p ≥ 0.05). CpG ODN increased placental expression of Per2 and Per3 and Tnfα ( p ≤ 0.05) and affected fetoplacental growth dynamics, such as reduced fetal and placental weights were disproportionately associated with increases in the number of resorptions in ODN-treated dams compared to controls. In conclusion, gestational exposure to unmethylated CpG DNA dysregulates placental molecular clock network and fetoplacental growth dynamics and disrupts blood pressure circadian rhythms.

Identification of underlying mechanisms and hub gene-miRNA networks of the genomic subgroups in preeclampsia development

Preeclampsia is a hypertensive disorder of pregnancy that can lead to multiorgan complications in the mother and fetus. Our study aims to uncover the underlying mechanisms and hub genes between genomic subgroups of preeclampsia. A total of 180 preeclampsia cases from 4 gene profiles were classified into 3 subgroups. Weighted gene coexpression analysis was performed to uncover the genomic characteristics associated with different clinical features. Functional annotation was executed within the significant modules and hub genes were predicted using Cytoscape software. Subsequently, miRNet analysis was performed to identify potential miRNA-mRNA networks. Three key subgroup-specific modules were identified. Patients in subgroup II were found to develop more severe preeclampsia symptoms. Subgroup II, characterized by classical markers, was considered representative of typical preeclampsia patients. Subgroup I was considered as an early stage of preeclampsia with normal-like gene expression patterns. Moreover, subgroup III was a proinflammatory subgroup, which presented immune-related genomic characteristics. Subsequently, miR-34a-5p and miR-106a-5p were found to be correlated with all 3 significant gene modules. This study revealed the transcriptome classification of preeclampsia cases with unique gene expression patterns. Potential hub genes and miRNAs may facilitate the identification of therapeutic targets for preeclampsia in future.

Recent advances in cancer immunotherapy: Modulation of tumor microenvironment by Toll-like receptor ligands

Immunotherapy is considered a promising approach for cancer treatment. An important strategy for cancer immunotherapy is the use of cancer vaccines, which have been widely used for cancer treatment. Despite the great potential of cancer vaccines for cancer treatment, their therapeutic effects in clinical settings have been limited. The main reason behind the lack of significant therapeutic outcomes for cancer vaccines is believed to be the immunosuppressive tumor microenvironment (TME). The TME counteracts the therapeutic effects of immunotherapy and provides a favorable environment for tumor growth and progression. Therefore, overcoming the immunosuppressive TME can potentially augment the therapeutic effects of cancer immunotherapy in general and therapeutic cancer vaccines in particular. Among the strategies developed for overcoming immunosuppression in TME, the use of toll-like receptor (TLR) agonists has been suggested as a promising approach to reverse immunosuppression. In this paper, we will review the application of the four most widely studied TLR agonists including agonists of TLR3, 4, 7, and 9 in cancer immunotherapy.

Phosphoglycerate mutase 5 promotes necroptosis in trophoblast cells through activation of dynamin-related protein 1 in early-onset preeclampsia

OBJECTIVES

Placentae from patients with preeclampsia have increased susceptibility to necroptosis and phosphoglycerate mutase 5 (PGAM5) plays a role in many necrosis pathways. We determined whether PGAM5 promotes necroptosis of trophoblast cells and the underlying mechanisms in this study.

METHODS

The injury model was established by treating JEG3 cells with hypoxia for 24 h. The functional measurements were assessed by the cell counting kit-8, propidium iodide (PI)/Annexin V staining, JC-1 staining and firefly luciferase ATP assay. The expression of proteins in human placentae and JEG3 cells was measured Western blot. PGAM5 was knocked down to study its role in hypoxia-induced necroptosis.

RESULTS

The placentae from patients with preeclampsia showed up-regulation of PGAM5 and decreased levels of p-Drp1-S637, accompanied by increased necroptosis-relevant proteins expression. The expression of PGAM5 in JEG3 cells was up-regulated under hypoxia, which promoted dephosphorylation of Drp1 at Serine 637 residue, mitochondrial dysfunction (elevated ROS level and reduced mitochondrial membrane potential and ATP content) and cellular necroptosis (increased PI⁺ /Annexin V⁺ cells and decreased cell viability), accompanied by increased expression of necroptosis-relevant proteins; knockdown of PGAM5 attenuated these phenomena.

CONCLUSIONS

Our results indicate that PGAM5 can promote necroptosis in trophoblast cells through, at least in part, activation of Drp1. It may be used as a new therapeutic target to prevent trophoblast dysfunction in preeclampsia.

Mitochondrial Dysfunction in the Pathogenesis of Preeclampsia

PURPOSE OF REVIEW

Preeclampsia complicates 5-10% of all pregnancies and is a leading cause of maternal and perinatal mortality and morbidity. The placenta plays a pivotal role in determining pregnancy outcome by supplying the fetus with oxygen and nutrients and by synthesizing hormones. Placental function is highly dependent on energy supplied by mitochondria. It is well-known that preeclampsia is originated from placental dysfunction, although the etiology of it remains elusive.

RECENT FINDINGS

During the last three decades, substantial evidence suggests that mitochondrial abnormality is a major contributor to placental dysfunction. In addition, mitochondrial damage caused by circulating bioactive factors released from the placenta may cause endothelial dysfunction and subsequent elevation in maternal blood pressure. In this review, we summarize the current knowledge of mitochondrial abnormality in the pathogenesis of preeclampsia and discuss therapeutic approaches targeting mitochondria for treatment of preeclampsia.

Neutrophil count is a useful marker to predict the severity of preeclampsia

BACKGROUND

At present, pre-eclampsia is a growing concern and still a diagnostic challenge for obstetricians.

AIMS

This study aimed to evaluate whether the relationship of second trimester of pregnancy neutrophil count differed among pregnancies with mild preeclampsia, severe preeclampsia, and healthy status and explore whether or not neutrophil count in the second trimester of pregnancy would be useful as new predictors of subsequent preeclampsia.

PATIENTS AND METHODS

This study involved 933 pregnancies from 1 January 2018 to 30 January 2021, comprising 396 healthy pregnancies, 222 pregnancies with mild preeclampsia, and 315 pregnancies with severe preeclampsia. The relationship between preeclampsia and neutrophil count was analyzed by multiple logistic regression. In addition, maternal placental tissues of three groups were immunohistochemically stained for myeloperoxidase (MPO).

RESULTS

Neutrophil count was significantly higher in pregnancies with preeclampsia (including pregnancies with mild and severe preeclampsia) than that in healthy pregnancies. The neutrophil count level was prominently higher in patients with severe preeclampsia compared with those with mild preeclampsia (p < .001). The neutrophil count level was significantly positively associated with preeclampsia after adjusting for gestational week at time of blood sampling, BMI, and age (β:1.23; 95%CI:1.09-1.36; p < .0001). In addition, MPO expressions of placental tissues in preeclamptic groups were significantly increased than these in healthy pregnant controls (p < .05).

CONCLUSIONS

Increased neutrophil count in the second trimester of pregnancy was significantly positively associated with preeclampsia. Hence, neutrophil count plays a role in predicting the severity of preeclampsia. At the same time, it may be an independent predictor of subsequent preeclampsia.Abbreviations: BMI: body mass index; MPO: myeloperoxidase.

Reduced Maternal Circulating Cell-Free Mitochondrial DNA Is Associated With the Development of Preeclampsia

Background Circulating cell-free mitochondrial DNA (ccf-mtDNA) is a damage-associated molecular pattern that reflects cell stress responses and tissue damage, but little is known about ccf-mtDNA in preeclampsia. The main objectives of this study were to determine (1) absolute concentrations of ccf-mtDNA in plasma and mitochondrial DNA content in peripheral blood mononuclear cells and (2) forms of ccf-mtDNA transport in blood from women with preeclampsia and healthy controls. In addition, we sought to establish the association between aberrance in circulating DNA-related metrics, including ccf-mtDNA and DNA clearance mechanisms, and the clinical diagnosis of preeclampsia using bootstrapped penalized logistic regression. Methods and Results Absolute concentrations of ccf-mtDNA were reduced in plasma from women with preeclampsia compared with healthy controls (P≤0.02), while mtDNA copy number in peripheral blood mononuclear cells did not differ between groups (P>0.05). While the pattern of reduced ccf-mtDNA in patients with preeclampsia remained, DNA isolation from plasma using membrane lysis buffer resulted in 1000-fold higher ccf-mtDNA concentrations in the preeclampsia group (P=0.0014) and 430-fold higher ccf-mtDNA concentrations in the control group (P<0.0001). Plasma from women with preeclampsia did not induce greater Toll-like receptor-9-induced nuclear factor kappa-light-chain enhancer of activated B cells-dependent responses in human embryonic kidney 293 cells overexpressing the human TLR-9 gene (P>0.05). Penalized regression analysis showed that women with preeclampsia were more likely to have lower concentrations of ccf-mtDNA as well as higher concentrations of nuclear DNA and DNase I compared with their matched controls. Conclusions Women with preeclampsia have aberrant circulating DNA dynamics, including reduced ccf-mtDNA concentrations and DNA clearance mechanisms, compared with gestational age-matched healthy pregnant women.

Circulating cell-free mitochondrial DNA in pregnancy

Circulating cell-free mitochondrial DNA (ccf-mtDNA) released upon cell injury or death stimulates diverse pattern recognition receptors to activate innate immune responses and initiate systemic inflammation. In this review, we discuss the temporal changes of ccf-mtDNA during pregnancy and its potential contribution to adverse pregnancy outcomes in pregnancy complications.

Vascular Dysfunction in Preeclampsia

Preeclampsia is a life-threatening pregnancy-associated cardiovascular disorder characterized by hypertension and proteinuria at 20 weeks of gestation. Though its exact underlying cause is not precisely defined and likely heterogenous, a plethora of research indicates that in some women with preeclampsia, both maternal and placental vascular dysfunction plays a role in the pathogenesis and can persist into the postpartum period. Potential abnormalities include impaired placentation, incomplete spiral artery remodeling, and endothelial damage, which are further propagated by immune factors, mitochondrial stress, and an imbalance of pro- and antiangiogenic substances. While the field has progressed, current gaps in knowledge include detailed initial molecular mechanisms and effective treatment options. Newfound evidence indicates that vasopressin is an early mediator and biomarker of the disorder, and promising future therapeutic avenues include mitigating mitochondrial dysfunction, excess oxidative stress, and the resulting inflammatory state. In this review, we provide a detailed overview of vascular defects present during preeclampsia and connect well-established notions to newer discoveries at the molecular, cellular, and whole-organism levels.

Systematic proteomics analysis of lysine acetylation reveals critical features of placental proteins in pregnant women with preeclampsia

Preeclampsia (PE) is a dangerous hypertensive disorder that occurs during pregnancy. The specific aetiology and pathogenesis of PE have yet to be clarified. To better reveal the specific pathogenesis of PE, we characterized the proteome and acetyl proteome (acetylome) profile of placental tissue from PE and normal-term pregnancy by label-free quantification proteomics technology and PRM analysis. In this research, 373 differentially expressed proteins (DEPs) were identified by proteome analysis. Functional enrichment analysis revealed significant enrichment of DEPs related to angiogenesis and the immune system. COL12A1, C4BPA and F13A1 may be potential biomarkers for PE diagnosis and new therapeutic targets. Additionally, 700 Kac sites were identified on 585 differentially acetylated proteins (DAPs) by acetylome analyses. These DAPs may participate in the occurrence and development of PE by affecting the complement and coagulation cascades pathway, which may have important implications for better understand the pathogenesis of PE. In conclusion, this study systematically analysed the reveals critical features of placental proteins in pregnant women with PE, providing a resource for exploring the contribution of lysine acetylation modification to PE.

CpG Oligodeoxynucleotide Developed to Activate Primate Immune Responses Promotes Antitumoral Effects in Combination with a Neoantigen-Based mRNA Cancer Vaccine

PURPOSE

The purpose of our research was to identify and evaluate synthetic phosphorothioate-modified CPG oligodeoxynucleotides (CPG-ODNs) activating innate and adaptive immune responses. Furthermore, combined treatment with CpG and an mRNA cancer vaccine was evaluated in melanoma models as a therapeutic approach.

METHODS

A molecular assay was used to screen new CpG molecules; mouse modeling and pathological analysis were used to confirm the antitumor effect of CpG alone or in combination with an mRNA vaccine. Finally, safety was assessed by monitoring blood biochemistry.

RESULTS

We first screened and identified a new CpG-B class ODN (CpG2018B) that effectively stimulated type II interferons in both mouse plasmacytoid dendritic cells (pDCs) and human peripheral blood mononuclear cells (PBMCs). In addition, CpG2018B promoted cytokine production mainly via toll-like receptor 9 (TLR9) pathways. We further demonstrated that intratumoral (IT) injection of CpG2018B inhibited melanoma growth in syngeneic models and could turn "cold" tumors into "hot" tumors. Then, CpG2018B and an mRNA-based neoantigen cancer vaccine were encapsulated in lipid nanoparticles (LNPs) and intratumorally injected into melanoma mouse models. Interestingly, vaccination with CpG or the mRNA vaccine alone could inhibit tumor growth, while combination of CpG with the mRNA vaccine enhanced the antitumor effect. Finally, we described the long-term safety and tolerability of CpG2018B and mRNA therapy in mice model.

CONCLUSION

We identified a novel CpG-B class ODN to promote the immune response, and CpG combined with mRNA cancer vaccines is an attractive candidate approach for immunostimulatory sequence (ISS)-based therapeutic strategies.

Toll-like receptor signaling is changed in ovine lymph node during early pregnancy

Toll-like receptors (TLRs) participate in regulation of adaptive immune responses, and lymph nodes play key roles in the initiation of immune responses. There is a tolerance to the allogenic fetus during pregnancy, but it is unclear that expression of TLR signaling is in ovine lymph node during early pregnancy. In this study, lymph nodes were sampled from day 16 of nonpregnant ewes and days 13, 16, and 25 of pregnant ewes, and the expressions of TLR family (TLR2, TLR3, TLR4, TLR5 and TLR9), adaptor proteins, including myeloid differentiation primary-response protein 88 (MyD88), tumor necrosis factor receptor associated factor 6 (TRAF6), and interleukin-1-receptor-associated kinase 1 (IRAK1), were analyzed through real-time quantitative polymerase chain reaction, Western blot, and immunohistochemistry analysis. The results showed that mRNA and protein levels of TLR2, TLR3, TLR4, TRAF6, and MyD88 were upregulated in the maternal lymph node, but TLR5, TLR9, and IRAK1 were downregulated during early pregnancy. In addition, MyD88 protein was located in the subcapsular sinus and lymph sinuses. Therefore, it is suggested that early pregnancy induces changes in TLR signaling in maternal lymph node, which may be involved in regulation of maternal immune responses in sheep.

Clinical characteristics, gestational weight gain and pregnancy outcomes in women with a history of gestational diabetes mellitus

BACKGROUND

Pregnant women with a history of gestational diabetes mellitus (GDM) are at high risk of GDM. It is unclear whether this population has pregnancy characteristics different from the general population. Whether these features affect the perinatal outcome has not yet been elucidated.

METHODS

A retrospective study was conducted, including baseline characteristics, laboratory data, gestational weight gain (GWG), and pregnancy outcomes of 441 pregnant women with prior GDM. Besides, 1637 women without a history of GDM treated in the same period were randomly selected as the control group. The above indicators of the two groups were compared. Multivariable logistic regression analysis was performed to investigate how GWG was associated with perinatal outcomes for previous GDM women.

RESULTS

Among women with GDM history, triglycerides (TG) and fasting plasma glucose (FPG) in the 1st trimester were higher than those without GDM history. GWG was lower in women with prior GDM relative to the control group at various pregnancy stages. However, women with GDM history had a higher risk of developing GDM (OR 3.25, 95% CI 2.26-4.68) and pregnancy-induced hypertension (OR 1.50, 95% CI 1.05-2.45). In women with previous GDM, excessive GWG before OGTT exhibited a positive correlation with pregnancy-induced hypertension (OR 1.47, 95% CI 1.05-3.32), while inadequate GWG was not a protective factor for GDM and pregnancy-induced hypertension.

CONCLUSION

Women with prior GDM have glucose and lipid metabolism disorders in the 1st trimester. Limited reduction of GWG before oral glucose tolerance test (OGTT) was insufficient to offset the adverse effects of glucose and lipid metabolism disorders in women with previous GDM. Relevant interventions may be required at early stage or even before pregnancy.

Gestational Diabetes Mellitus and Maternal Immune Dysregulation: What We Know So Far

Gestational diabetes mellitus (GDM) is an obstetric complication that affects approximately 5-10% of all pregnancies worldwide. GDM is defined as any degree of glucose intolerance with onset or first recognition during pregnancy, and is characterized by exaggerated insulin resistance, a condition which is already pronounced in healthy pregnancies. Maternal hyperglycaemia ensues, instigating a 'glucose stress' response and concurrent systemic inflammation. Previous findings have proposed that both placental and visceral adipose tissue play a part in instigating and mediating this low-grade inflammatory response which involves altered infiltration, differentiation and activation of maternal innate and adaptive immune cells. The resulting maternal immune dysregulation is responsible for exacerbation of the condition and a further reduction in maternal insulin sensitivity. GDM pathology results in maternal and foetal adverse outcomes such as increased susceptibility to diabetes mellitus development and foetal neurological conditions. A clearer understanding of how these pathways originate and evolve will improve therapeutic targeting. In this review, we will explore the existing findings describing maternal immunological adaption in GDM in an attempt to highlight our current understanding of GDM-mediated immune dysregulation and identify areas where further research is required.

HDAC2-mediated proliferation of trophoblast cells requires the miR-183/FOXA1/IL-8 signaling pathway

Pre-eclampsia (PE) is a major cause of maternal and perinatal death. Previous research has indicated the role of histone deacetylase 2 (HDAC2) in the pathogenesis of PE but the relevant molecular mechanisms are unknown. However, there is hitherto little information concerning the molecular mechanism behind HDAC2 in PE. Herein, we hypothesized that HDAC2 promotes trophoblast cell proliferation and this requires the involvement of microRNA-183 (miR-183), forkhead box protein A1 (FOXA1), and interleukin 8 (IL-8). We collected placental specimens from 30 PE affected and 30 normal pregnant women. HDAC2 and FOXA1 were poorly expressed while miR-183 and IL-8 were highly expressed in placental tissues in PE. In vitro, HDAC2 overexpression enhanced the proliferation, migration, and invasion of human trophoblast cells HTR-8/SVNEO. HDAC2 inhibited the expression of miR-183 by diminishing H4 acetylation in the miR-183 promoter region. miR-183 inhibition by its specific inhibitor increased the expression of FOXA1 and thus enhanced HTR-8/SVNEO cell proliferation, migration, and invasion. FOXA1, a transcriptional factor, enhanced HTR-8/SVNEO cell proliferation, migration, and invasion by inhibiting the transcription of IL-8. We also observed HDAC2 knockdown was lost upon FOXA1 overexpression, suggesting that HDAC2 could promote HTR-8/SVNEO proliferation, migration, and invasion through the miR-183/FOXA1/IL-8 pathway. In summary, the results highlighted the role of the HDAC2/miR-183/FOXA1/IL-8 pathway in PE pathogenesis and thus suggest a novel molecular target for PE.

Preeclampsia and Neurodevelopmental Outcomes: Potential Pathogenic Roles for Inflammation and Oxidative Stress?

Preeclampsia (PE) is a common and serious hypertensive disorder of pregnancy that occurs in approximately 3-5% of first-time pregnancies and is a well-known leading cause of maternal and neonatal mortality and morbidity. In recent years, there has been accumulating evidence that in utero exposure to PE acts as an environmental risk factor for various neurodevelopmental disorders, particularly autism spectrum disorder and ADHD. At present, the mechanism(s) mediating this relationship are uncertain. In this review, we outline the most recent evidence implicating a causal role for PE exposure in the aetiology of various neurodevelopmental disorders and provide a novel interpretation of neuroanatomical alterations in PE-exposed offspring and how these relate to their sub-optimal neurodevelopmental trajectory. We then postulate that inflammation and oxidative stress, two prominent features of the pathophysiology of PE, are likely to play a major role in mediating this association. The increased inflammation in the maternal circulation, placenta and fetal circulation in PE expose the offspring to both prenatal maternal immune activation-a risk factor for neurodevelopmental disorders, which has been well-characterised in animal models-and directly higher concentrations of pro-inflammatory cytokines, which adversely affect neuronal development. Similarly, the exaggerated oxidative stress in the mother, placenta and foetus induces the placenta to secrete factors deleterious to neurons, and exposes the fetal brain to directly elevated oxidative stress and thus adversely affects neurodevelopmental processes. Finally, we describe the interplay between inflammation and oxidative stress in PE, and how both systems interact to potentially alter neurodevelopmental trajectory in exposed offspring.

Oxidative stress and mitochondrial dysfunction in early-onset and late-onset preeclampsia

Preeclampsia is a pregnancy-specific syndrome with multisystem involvement which leads to foetal, neonatal, and maternal morbidity and mortality. This syndrome is characterized by the onset of clinical signs and symptoms and delivery before (early-onset preeclampsia, eoPE), or after (late-onset preeclampsia, loPE), the 34 weeks of gestation. Preeclampsia is a mitochondrial disorder where its differential involvement in eoPE and loPE is unclear. Mitochondria regulate cell metabolism and are a significant source of reactive oxygen species (ROS). The syncytiotrophoblast in eoPE and loPE show altered mitochondrial structure and function resulting in ROS overproduction, oxidative stress, and cell damage and death. Mitochondrial dysfunction in eoPE may result from altered expression of several molecules, including dynamin-related protein 1 and mitofusins, compared with loPE where these factors are either reduced or unaltered. Equally, mitochondrial fusion/fission dynamics seem differentially modulated in eoPE and loPE. It is unclear whether the electron transport chain and oxidative phosphorylation are differentially altered in these two subgroups of preeclampsia. However, the activity of complex IV (cytochrome c oxidase) and the expression of essential proteins involved in the electron transport chain are reduced, leading to lower oxidative phosphorylation and mitochondrial respiration in the preeclamptic placenta. Interventional studies in patients with preeclampsia using the coenzyme Q₁₀, a key molecule in the electron transport chain, suggest that agents that increase the antioxidative capacity of the placenta may be protective against preeclampsia development. In this review, the mitochondrial dysfunction in both eoPE and loPE is summarized. Therapeutic approaches are discussed in the context of contributing to the understanding of mitochondrial dysfunction in eoPE and loPE.

Mitochondrial function in immune cells in health and disease

One of the main functions of mitochondria is production of ATP for cellular energy needs, however, it becomes more recognized that mitochondria are involved in differentiation and activation processes of immune cells. Upon activation, immune cells have a high need for energy. Immune cells have different strategies to generate this energy. In pro-inflammatory cells, such as activated monocytes and activated T and B cells, the energy is generated by increasing glycolysis, while in regulatory cells, such as regulatory T cells or M2 macrophages, energy is generated by increasing mitochondrial function and beta-oxidation. Except for being important for energy supply during activation, mitochondria also induce immune responses. During an infection, they release mitochondrial danger associated molecules (DAMPs) that resemble structures of bacterial derived pathogen associated molecular patterns (PAMPs). Such mitochondrial DAMPS are for instance mitochondrial DNA with hypomethylated CpG motifs or a specific lipid that is only present in prokaryotic bacteria and mitochondria, i.e. cardiolipin. Via release of such DAMPs, mitochondria guide the immune response towards an inflammatory response against pathogens. This is an important mechanism in early detection of an infection and in stimulating and sustaining immune responses to fight infections. However, mitochondrial DAMPs may also have a negative impact. If mitochondrial DAMPs are released by damaged cells, without the presence of an infection, such as after a trauma, mitochondrial DAMPs may induce an undesired inflammatory response, resulting in tissue damage and organ dysfunction. Thus, immune cells have developed mechanisms to prevent such undesired immune activation by mitochondrial components. In the present narrative review, we will describe the current view of mitochondria in regulation of immune responses. We will also discuss the current knowledge on disturbed mitochondrial function in immune cells in various immunological diseases.

Mechanisms of Endothelial Dysfunction in Pre-eclampsia and Gestational Diabetes Mellitus: Windows Into Future Cardiometabolic Health?

Placental insufficiency and adipose tissue dysregulation are postulated to play key roles in the pathophysiology of both pre-eclampsia (PE) and gestational diabetes mellitus (GDM). A dysfunctional release of deleterious signaling motifs can offset an increase in circulating oxidative stressors, pro-inflammatory factors and various cytokines. It has been previously postulated that endothelial dysfunction, instigated by signaling from endocrine organs such as the placenta and adipose tissue, may be a key mediator of the vasculopathy that is evident in both adverse obstetric complications. These signaling pathways also have significant effects on long term maternal cardiometabolic health outcomes, specifically cardiovascular disease, hypertension, and type II diabetes. Recent studies have noted that both PE and GDM are strongly associated with lower maternal flow-mediated dilation, however the exact pathways which link endothelial dysfunction to clinical outcomes in these complications remains in question. The current diagnostic regimen for both PE and GDM lacks specificity and consistency in relation to clinical guidelines. Furthermore, current therapeutic options rely largely on clinical symptom control such as antihypertensives and insulin therapy, rather than that of early intervention or prophylaxis. A better understanding of the pathogenic origin of these obstetric complications will allow for more targeted therapeutic interventions. In this review we will explore the complex signaling relationship between the placenta and adipose tissue in PE and GDM and investigate how these intricate pathways affect maternal endothelial function and, hence, play a role in acute pathophysiology and the development of future chronic maternal health outcomes.

Associations between pre-pregnancy body mass index and gestational weight gain with pregnancy outcomes in women with polycystic ovary syndrome

BACKGROUND

The influence of pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) on perinatal outcomes of women with polycystic ovary syndrome (PCOS) remains unclear. Therefore, we explored how the above indicators influence pregnancy outcomes in women with PCOS.

METHODS

A retrospective study was conducted involving the baseline characteristics, laboratory data, and pregnancy outcomes of 722 pregnant women with PCOS. Subjects were grouped in a way to find out risks in their pregnancy outcomes. Multivariable logistic regression analysis was performed to investigate how BMI and GWG were associated with perinatal outcomes.

RESULTS

Among women with PCOS, underweight increased the risk of small for gestational age (SGA) (OR 12.35, 95% CI 3.56-42.82), but reduced the risk of large for gestational age (LGA). Overweight but not obese women were more susceptible to developing preeclampsia (PE) than women with normal weight. In PCOS women with BMI < 25 kg/m² before pregnancy, inadequate GWG was a protective factor for gestational hypertension (GH) and postpartum hemorrhage (PPH), excessive GWG exhibited a positive correlation with LGA. But in PCOS women with BMI ≥ 25 kg/m², excessive GWG increased the probability of undergoing a cesarean section. Inadequate GWG did not reduce the likelihood of LGA in women with BMI ≥ 25 kg/m², and excessive GWG did not reduce the probability of SGA in women with BMI < 25 kg/m².

CONCLUSION

The impacts of pre-pregnancy BMI, GWG on maternal and infant outcomes among PCOS women are similar to reported results in general pregnant women. However, some unique trends were also observed in PCOS women. While the underweight factor significantly increased the risk of SGA birth, overweight but not obesity was correlated with the risk of PE. Inadequate GWG was a protective factor for GH and PPH only in women with pregestational BMI < 25 kg/m². Inadequate GWG did not reduce the probability of LGA in women with BMI ≥ 25 kg/m², and similarly, excessive GWG did not reduce the probability of SGA in women with BMI < 25 kg/m². Overall, these findings indicate that women with PCOS should begin weight management before pregnancy.