MiR-141-3p promotes hypoxia-induced autophagy in human placental trophoblast cells

Preeclampsia (PE) is a pregnancy-specific disorder and a significant contributor to maternal, fetal and neonatal morbidity and mortality worldwide. Its pathogenesis is generally accepted as insufficient trophoblast invasion of the maternal endometrium and inadequate remodeling of the maternal spiral arteries. These impairments lead to elevated levels of hypoxia and oxidative stress. Autophagy has become a highly researched field in obstetrics, and this process may be essential for preimplantation development beyond the four- and eight-cell stages, and for blastocyst survival, extra-villous trophoblast functions, invasion and vascular remodeling. Several studies have shown that autophagy activation, shown by an increase in autophagy vacuoles or microtubule-associated protein 1 A/1B-light chain 3 (LC3) dots, was more common in PE than in normal pregnancy. Thus, changes in autophagic status are seen in preeclamptic placentas. MicroRNA-141-3p (miR-141-3p), a multifunctional miRNA, is involved in a variety of physiological and pathological processes, including PE and autophagy. However, the influence of miR-141-3p on autophagy regulation in trophoblast cells has yet to be described. Therefore, the objective of our study was to investigate the role of miR-141-3p in autophagy induced by hypoxia in human placental trophoblast cells. Our results found that hypoxia induced autophagy in trophoblast cells and dramatically elevated the expression of miR-141-3p. Overexpression of miR-141-3p improved autophagic activity, whereas low expression of miR-141-3p inhibited autophagic activity. Therefore, our data demonstrated that miR-141-3p promoted hypoxia-induced autophagy in placental trophoblast cells, which may be related to the development of preeclampsia.

Epigenetics and Pregnancy: Conditional Snapshot or Rolling Event

Epigenetics modification such as DNA methylation can affect maternal health during the gestation period. Furthermore, pregnancy can drive a range of physiological and molecular changes that have the potential to contribute to pathological conditions. Pregnancy-related risk factors include multiple environmental, behavioral, and hereditary factors that can impact maternal DNA methylation with long-lasting consequences. Identification of the epigenetic patterns linked to poor pregnancy outcomes is crucial since changes in DNA methylation patterns can have long-term effects. In this review, we provide an overview of the epigenetic changes that influence pregnancy-related molecular programming such as gestational diabetes, immune response, and pre-eclampsia, in an effort to close the gap in current understanding regarding interactions between the environment, the genetics of the fetus, and the pregnant woman.

Triglyceride Induced Metabolic Inflammation: Potential Connection of Insulin Resistance and Recurrent Pregnancy Loss

The underlying correlative mechanisms between Insulin resistance (IR) and recurrent pregnancy loss (RPL) in patients without polycystic ovarian syndrome (PCOS) remain inconclusive. To investigate the association between triglyceride (TG) levels, lymphocyte subsets, and IR in RPL patients without PCOS and obesity. Eighty-nine subjects with an unexplained RPL, independent of PCOS/obesity were enrolled in this study. A 75-g oral glucose tolerance test was performed on each subject with plasma tested for glucose and insulin. The fasting venous blood of all subjects was collected for routine clinical chemistry analysis. Lymphocyte subsets were analyzed by four-color flow cytometry. As a result, TG levels were significantly elevated in RPL patients with IR compared to those without IR. Pearson linear correlation model and receiver operating characteristic (ROC) curve analyses revealed a significant positive association between TG and HOMA-IR index value. In multiple logistic regression analysis, TG was significantly associated with the risk of hyperinsulinemia and increased CD3⁺CD4⁺/CD3⁺CD8⁺ ratio which was significantly negatively correlated with disposition index (DI30) and DI120, indicators for insulin sensitivity. In addition, DI30 and DI120 were significantly decreased in the higher CD3⁺CD4⁺/CD3⁺CD8⁺ group. Our findings showed that the elevated TG and altered immune responses in RPL patients with IR are independent of PCOS and obesity, and could be used as an indicator of IR in RPL patients. These results contribute to the understanding of the pathophysiology of IR in RPL for potential prevention and therapeutic targets.

Deficiency of the oxidative stress-responsive kinase p70S6K1 restores autophagy and ameliorates neural tube defects in diabetic embryopathy

BACKGROUND

Autophagy is highly active in neuroepithelial cells of the developing neuroepithelium, and impairment of autophagy leads to neural tube defects. In this study, we have found that maternal diabetes suppresses autophagy that leads to neural tube defects and consequent cellular imbalance in the endoplasmic reticulum where critical events occur, leading to the induction of diabetic embryopathy. Because the mammalian target of rapamycin pathway suppresses autophagy, we hypothesized that 70 kDa ribosomal protein S6 kinase 1 (p70S6K1), a major downstream effector of mammalian target of rapamycin, mediates the inhibitory effect of maternal diabetes on autophagy in the developing neuroepithelium.

OBJECTIVE

We investigated whether p70S6K1 mediates the inhibitory effect of maternal diabetes on autophagy during neurulation. We also examined whether p70S6K1 deficiency restores autophagy and therefore relieves endoplasmic reticulum stress and inhibits maternal diabetes-induced apoptosis, which leads to reduction in neural tube defect incidence in diabetic embryopathy.

STUDY DESIGN

Female p70S6K1 heterogeneous knockout (p70S6K1+/-) mice were bred with male p70S6K1 heterogeneous knockout (p70S6K1+/-) mice to generate wild-type (WT), p70S6K1+/- and p70S6K1 knockout (p70S6K1-/-) embryos. Embryos at embryonic day 8.5 were harvested for the assessment of indices of autophagy, endoplasmic reticulum stress, and apoptosis. Neural tube defect incidence in embryos was determined at embryonic day 10.5. For in vitro studies, small interfering RNA knockdown of p70S6K1 in C17.2 mouse neural stem cells was used to determine the effect of p70S6K1 deficiency on autophagy impairment and endoplasmic reticulum stress under high glucose conditions.

RESULTS

Knockout of the Rps6kb1 gene, which encodes for p70S6K1, ameliorated maternal diabetes-induced NTDs and restored autophagosome formation in neuroepithelial cells suppressed by maternal diabetes. Maternal diabetes-suppressed conversion of LC3-I (microtubule-associated protein 1A/1B-light chain 3) to LC3-II, an index of autophagic activity, in neurulation stage embryos was abrogated in the absence of p70S6K1. p70S6K1 knockdown in neural stem cells also restored autophagosome formation and the conversion of LC3-I to LC3-II. The activation of the major unfolded protein response, indicated by phosphorylation of inositol-requiring enzyme 1 alpha, and protein kinase R-like endoplasmic reticulum kinase, and eukaryotic translation initiation factor 2α, and the increase of the endoplasmic reticulum stress marker, C/EBP homologous protein, were induced by maternal diabetes in vivo and high glucose in vitro. Unfolded protein response and endoplasmic reticulum stress induced by maternal diabetes or high glucose were reduced by Rps6kb1 deletion or p70S6K1 knockdown, respectively. Rps6kb1 knockout blocked maternal diabetes-induced caspase cleavage and neuroepithelial cell apoptosis. The superoxide dismutase mimetic Tempol abolished high glucose-induced p70S6K1 activation.

CONCLUSION

The study revealed the critical involvement of p70S6K1 in the pathogenesis of diabetic embryopathy.

Physiological and pathological regulation of autophagy in pregnancy

Autophagy exists widely in eukaryotic cells and is regulated by a variety of molecular mechanisms. Its physiological functions include providing energy, maintaining cell homeostasis, and promoting apoptosis of abnormal cells. At present, the regulation of autophagy in tumor, degenerative disease, and cardiovascular disease has attracted much attention. Gradually, the role of autophagy in pregnancy tends to be valued. The previous literature has shown that autophagy can influence the occurrence and maintenance of pregnancy from three aspects: embryo (affecting the process of fertilization and embryonic development and the function of trophoblast cells), maternal (decidualization), and maternal-to-fetal immune crosstalk. Undoubtedly, abnormalities in autophagy levels are associated with a variety of pregnancy complications, such as preeclampsia, fetal growth restriction, and preterm delivery which have been proven by human, animal, and in vitro experiments. The regulation of autophagy is expected to be a target for the treatment of these pregnancy complications. This article reviews the research on autophagy, especially about its physiological and pathological regulation during pregnancy.

Soluble T cell immunoglobulin mucin domain 3 (sTim-3) in maternal sera: a potential contributor to immune regulation during pregnancy

Objective: The immune checkpoint inhibitor, membrane-bound T cell immunoglobulin mucin domain 3 (Tim-3), binds to galectin-9 (gal-9) and promotes immune tolerance during pregnancy. Soluble Tim-3 (sTim-3) competes with Tim-3 for binding to gal-9 and modulates its activity. Our objective was to evaluate the influence of sTim-3 on immune responses and outcome in pregnant women.Study design: Peripheral blood from 71 pregnant women was separated into mononuclear cell (PBMC) and plasma fractions. The PBMCs were lysed and tested for Tim-3 by ELISA. Plasma was assayed for sTim-3, gal-9, tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10) and the stress-inducible 70 kDa heat shock protein (hsp70) by enzyme-linked immunosorbent assay (ELISA). Correlations were analyzed by the Spearman rank correlation test.Results: The higher the sTim-3 level in plasma the lower was the PBMC Tim-3 concentration (p = .0135), suggesting that sTim-3 results from the release of membrane-bound Tim-3. Plasma sTim3 levels were positively correlated with levels of gal-9 (p < .0001), TNF-α (p = .0071) and hsp70 (p = .0144), but not with IL-10. The sTim-3 level was positively associated (p = .0276) with gestational age at delivery. There was no association between sTim-3 and gestational age at sample collection, maternal age, gravidity, parity or body mass index.Conclusion: The release of Tim-3 from membranes and sTim-3 reacting with gal-9 may increase proinflammatory immunity and the stress response. The release of sTim-3 from lymphoid cells into the circulation and its binding to gal-9 may modulate Tim-3-mediated activity and help optimize immune regulation during pregnancy.

Unique Associations between Insulin-Like Growth Factor Binding Protein-1, Insulin-Like Growth Factor-1 and T Cell Immunoglobulin Mucin 3 in Successful Twin Pregnancies Conceived with Donor Oocytes

Background and Objectives: To investigate if pregnancies conceived using an oocyte donor necessitate an alteration in immune regulation, we compared concentrations of insulin-like growth factor binding protein (IGFBP)-1, insulin-like growth factor (IGF)-1 and T cell immunoglobulin mucin-3 (Tim-3) in women with ongoing successful twin pregnancies conceived spontaneously, using assisted reproductive technologies that utilized homologous oocytes or with donor oocytes. Differences in levels of these immune modulatory proteins may be magnified and easier to detect in twin as compared to singleton pregnancies. Methods: In this prospective study IGFBP-1 and IGF-1 were measured in sera and Tim-3 in lysates of peripheral blood mononuclear cells (PBMCs) by ELISA. Results: Median IGFBP-1 levels were lower in women with donor oocytes (41.4 ng/ml) as compared to those with a spontaneous conception (51.2 ng/mL) or who conceived with various assisted reproduction protocols using homologous oocytes (52.4 ng/mL) (p < 0.001). IGF-1 and Tim-3 levels were comparable in each group. The IGFBP-1 level was inversely correlated to the IGF-1 concentration only in women with donor oocytes (p = 0.032). IGFBP-1 and Tim-3 levels were similarly negatively correlated in the donor oocyte group (p = 0. 012). Women in the assisted reproduction group who conceived following intracytoplasmic sperm injection were the only other group in which IGFBP-1 and Tim-3 were negatively correlated (p = 0.018). Conclusions: Down-regulation of IGFBP-1 production in pregnancies conceived with donor oocytes may reduce the extent of pro-inflammatory immunity and contribute to successful outcome in totally allogeneic pregnancies.

Sex-specific influence of the vacuolar adenosine triphosphatase a2 isoform on outcome in twin pregnancies

PROBLEM

The influence of fetal sex on immune responses in multifetal pregnancies remains incompletely elucidated. The a2 isoform of vacuolar adenosine triphosphatase (a2V) is expressed on the cell membrane of maternal lymphoid cells and contributes to down-regulation of pro-inflammatory immune responses during gestation. The association between fetal sex and a2V expression on peripheral blood mononuclear cells (PBMCs) from mothers with twin gestations was assessed.

METHOD OF STUDY

Patients in this prospective study were 93 women with twin pregnancies in their mid-second or early third trimester-27 with two male, 30 with two female and 36 with one male and one female fetus. PBMCs were isolated and a2V was measured by ELISA in cell lysates. Demographic and clinical data were subsequently obtained and correlations between a2V and fetal sex, birthweight and pregnancy outcome were assessed by the Mann-Whitney and Spearman rank correlation tests.

RESULTS

The mean a2V level was highest when both fetuses were male (2.0 ng/mL) and lowest when both were female (1.5 ng/mL; P = 0.0184). Only when both fetuses were female did the a2V concentration negatively correlate with birthweight of the 1st (P = 0.0011) and 2nd (P = 0.0044) born fetus and with gestational age at delivery (P = 0.0018). There were no associations between a2V and these outcomes in male only or mixed twin pregnancies.

CONCLUSION

We conclude that the a2V-mediated regulation of maternal immunity during twin pregnancies is influenced by fetal sex.

T-cell immunoglobulin mucin-3 and galectin-9 levels in peripheral blood mononuclear cells predict fetal acidemia in twin pregnancies

Purposes: The pH in the umbilical artery at delivery provides information on the fetal environment and is related to postnatal outcomes. The ability to predict fetal acidemia at delivery would improve clinical management and neonatal well-being. We hypothesized that an alteration in maternal immunity would accompany placental changes that precede a decrease in pH in the fetal circulation in twin gestations.Methods: Peripheral blood mononuclear cells (PBMCs), obtained from 86 women with twin pregnancies, were lysed and assayed for concentrations of T-cell immunoglobulin mucin domain 3 (Tim-3) and galectin-9 (gal-9) by ELISA. Tim-3-gal-9 interaction is a primary mechanism promoting immune suppression. At delivery, the pH of arterial cord blood was determined.Results: In eight women (9.3%), the pH in the placental arteries from both twins was <7.15, indicating fetal acidosis. In the remaining 78 women the arterial pH was ≥7.15 in both twins. The median Tim-3 level was 361 pg/ml when arterial pH was <7.15 and 199 pg/ml when pH was ≥7.15 (p = .003). Similarly, gal-9 was 31.2 versus 12.4 ng/ml when pH was <7.15 or ≥7.15, respectively (p = .001). A Tim-3 concentration >260 pg/ml predicted arterial pH <7.15 with a sensitivity of 87.5%, specificity of 79.5% and negative predictive value of 98.4%. A gal-9 level >18.4 predicted arterial pH <7.15 with a sensitivity of 100%, specificity of 73.8% and a negative predictive value of 100%.Conclusion: We conclude that elevations in Tim-3 and gal-9 in PBMCs during gestation predict the subsequent occurrence of a pH <7.15 in the fetal arteries at delivery in twin gestations.

Insulin resistance in patients with recurrent pregnancy loss is associated with lymphocyte population aberration

This study was designed to investigate the relationship of insulin resistance (IR) and cellular immune abnormalities associated with women with recurrent pregnancy loss (RPL). Women with RPL were divided into two groups according to their homeostasis model assessment for IR (HOMA-IR) scores. The IR group received metformin approximately 3 months before pregnancy. The percentage of lymphocyte subsets and other blood biochemical indices were tested. The HOMA-IR and fasting serum insulin levels were related to the percentage of lymphocyte subsets. The women with RPL had higher CD3⁺ and CD3⁺CD4⁺ cell levels while CD56⁺CD16⁺cell levels were lower. A higher likelihood of cellular immune abnormalities was observed. Women with normal lymphocyte subsets had normal pregnancy outcomes. Metformin significantly downregulated CD3⁺ and CD3⁺CD4⁺ cells and improved pregnancy outcomes. IR was associated with cellular immune abnormalities in RPL. The data suggests that metformin affected the immune/inflammatory response, which may regulate the cellular immune balance and improve pregnancy outcomes. Abbreviations RPL: recurrent pregnancy loss; IR insulin resistance; HOMA-IR: homeostasis model assessment for IR.

The Role of Hsp70 in the Regulation of Autophagy in Gametogenesis, Pregnancy, and Parturition

Induction of the 70 kDa heat shock protein (hsp70) and autophagy are two major mechanisms that promote cell homeostasis during the rapid cell growth and differentiation characteristic of reproduction. Hsp70 insures proper assembly, conformation, and intracellular transport of nascent proteins. Autophagy removes from the cytoplasm proteins, other macromolecules, and organelles that are no longer functional or needed and recycles their components for synthesis of new products under nutritionally limiting conditions. Hsp70 inhibits autophagy and so a proper balance between these two processes is essential for optimal germ cell production and survival and pregnancy progression. A marked inhibition in autophagy and a concomitant increase in hsp70 at term is a trigger for parturition. Excessive external or endogenous stress that induces a high level of hsp70 production can lead to a non-physiological inhibition of autophagy, resulting in altered spermatogenesis, premature ovarian failure, and complications of pregnancy including preeclampsia, intrauterine growth restriction, and preterm birth.

Diagnostic Significance of Phosphoinositide 3-Kinase and Mammalian Target of Rapamycin Complex 1 in Preeclampsia

OBJECTIVE

To examine the association of phosphoinositide 3-kinase (PI3K) and mammalian target of rapamycin complex 1 (m-TORC1) with preeclampsia (PE) and to explore their diagnostic significance in PE.

METHODS

A total of 153 singleton pregnant women were enrolled into our study, among which there were 97 patients with PE (mild PE [MPE]: n = 51; severe PE [SPE]: n = 46) and 56 healthy pregnant women (normal controls, NCs). Enzyme-linked immunosorbent assay (ELISA) and Western blot were used in this study. Moreover, a receiver-operating characteristic (ROC) curve was used to estimate the diagnostic significance.

RESULTS

After adjustment for confounding factors, at 24 to 28 gestational weeks, the serum levels of PI3K and m-TORC1 were both higher in the MPE and the SPE groups compared to those in the NC group (all P < .001). The serum levels of PI3K were positively correlated with the serum levels of m-TORC1 in both the NC and the PE groups at both 15 to 21 and 24 to 28 gestational weeks (both P < .001). Multivariable linear regression indicated that both PI3K and m-TORC1 were positively correlated with the systolic pressure (both P < .001). At 24 to 28 gestational weeks, there remained relatively high sensitivity and specificity when the serum levels of PI3K and m-TORC1 were used to diagnose PE (both P < .001). A Western blot assay found that there were significant differences in the PI3K and m-TORC1 protein expression among the 3 groups (all P < .001).

CONCLUSION

The serum levels of PI3K and m-TORC1 might have the potential to diagnose PE, while PI3K and m-TORC1 fail to predict PE during early pregnancy.

The influence of oxidative stress and autophagy cross regulation on pregnancy outcome

The generation of reactive oxygen species (ROS), a byproduct of aerobic energy metabolism, is maintained at physiological levels by the activity of antioxidant components. Insufficiently opposed ROS results in oxidative stress characterized by altered mitochondrial function, decreased protein activity, damage to nucleic acids, and induction of apoptosis. Elevated levels of inadequately opposed ROS induce autophagy, a major intracellular pathway that sequesters and removes damaged macromolecules and organelles. In early pregnancy, autophagy induction preserves trophoblast function in the low oxygen and nutrient placental environment. Inadequate regulation of the ROS-autophagy axis leads to abnormal autophagy activity and contributes to the development of preeclampsia and intrauterine growth restriction. ROS-autophagy interactions are altered at the end of gestation and participate in the initiation of parturition at term. The induction of high levels of ROS coupled with a failure to induce a corresponding increase in autophagy results in the triggering of preterm labor and delivery.

Group B streptococcus alters properties of vaginal epithelial cells in pregnant women

BACKGROUND

Group B streptococcus (GBS) infection in pregnancy is a major cause of maternal and neonatal morbidity. An understanding of the mechanisms responsible for GBS persistence in the genital tract, as well as recognition of host defenses employed to combat its presence, are crucial to our efforts to reduce maternal GBS colonization and prevent the acquisition of neonatal infections. However, alterations in vaginal immunity in response to GBS colonization in pregnant women remain incompletely defined. Whether GBS modulates autophagy, a major host defense mechanism and contributor to the control of intracellular microbial infections, also remains unclear.

OBJECTIVE

We sought to identify differences in the extent of autophagy as well as in the concentration of biomarkers previously shown to be involved in vaginal innate immunity between GBS-positive and GBS-negative pregnant women.

STUDY DESIGN

We performed a prospective cohort study of healthy pregnant women, who had vaginal secretions obtained at 35-37 weeks of gestation, just prior to the standard GBS rectovaginal sample collection. The contents of the swabs were released into tubes containing 1 mL of sterile phosphate-buffered saline. Samples were centrifuged, and supernatant and cell pellet fractions were collected and stored separately at -80°C until used for analysis. Epithelial cells were then lysed, and the extent of autophagy was determined by measuring the residual level of p62 remaining in the cytoplasm. p62 is a protein that is consumed during autophagy, and so its concentration detectable in the cytoplasm is inversely related to the extent of autophagy induction. The intracellular level of the inducible 70-kDa heat shock protein (hsp70), an inhibitor of autophagy, was also measured. The cell-free fraction was assayed for D- and L-lactic acid, neutrophil gelatinase-associated lipocalin, extracellular matrix metalloproteinase inducer (EMMPRIN), matrix metalloproteinase (MMP)-8, alpha amylase, hyaluronan, and total protein. Laboratory personnel were blinded to all clinical data.

RESULTS

There were 145 women included in the study, of which 45 (31%) were culture-positive for GBS. Vaginal cells from GBS-positive women had elevated intracellular levels of p62 (2.1 vs 0.7 pg/mL, P < .01) and hsp70 (16.9 vs 9.6 ng/mL, P = .03) as compared to GBS-negative women. The p62 and hsp70 levels were highly correlated in both groups of subjects (P < .01). In vaginal fluid, concentrations of neutrophil gelatinase-associated lipocalin (1.1 vs 0.7 ng/μg total protein, P = .01), MMP-8 (21.9 vs 11.1 pg/μg total protein, P = .01), and extracellular MMP inducer (8.8 vs 7.2 pg/μg total protein, P = .03) were highest in GBS-positive women. There were no differences in the concentrations of D- and L-lactic acid, alpha amylase, or hyaluronan between the 2 groups of women.

CONCLUSION

The inhibition of autophagy in vaginal epithelial cells by GBS-induced hsp70 production is associated with its persistence. Concurrently, alterations in components known to influence vaginal bacterial colonization or facilitate microbial passage to the upper genital tract also occur in relation to GBS carriage.

Maternal immunity and pregnancy outcome: focus on preconception and autophagy

Modulation of the maternal immune system before conception has a major role in determining subsequent pregnancy outcome. However, this has been a neglected area of investigation. There is a correlation between the length of time a woman is exposed to semen from her male partner and the development of regulatory T cells that limit a maternal antifetal immune response. Similarly, the composition of the vaginal microbiota influences the capacity of microorganisms to bypass the cervical barrier and colonize the uterus before pregnancy. The extent that this preconception colonization influences pre- and post-implantation gestational events depends on the types of microbes present, the genetic make-up of the mother and environmental influences on the magnitude and direction of her immune responses. Prepregnancy uterine and placental colonization with commensal bacteria may be beneficial to the fetus and newborn by generating tolerance to organisms that enhance postnatal well-being. Efforts to prevent or stop the progression of premature myometrial contractions have been limited because of an incomplete understanding of the mechanism(s) that trigger this occurrence. Based on recent studies of autophagy during gestation and parturition, inhibition of autophagy in myometrial cells may be the critical factor leading to a sequence of events culminating in induction of myometrial contractions either prematurely or at term.

Autophagy, which is decreased in labouring fetal membranes, regulates IL-1β production via the inflammasome

INTRODUCTION

IL-1β plays a vital role in the terminal processes of human labour and delivery. Inflammasome activation is required to process pro IL-1β to an active, secreted molecule. Recent studies have shown that autophagy regulates IL-1β via the inflammasome. The aims were to determine the effect of (i) human spontaneous term and preterm labour on the expression of autophagy proteins in fetal membranes; and (ii) autophagy inhibition on IL-1β release.

METHODS

Fetal membranes, from term and preterm, were obtained from non-labouring and labouring women. Tissue explants were used to determine the effect of inhibition of autophagy on IL-1β secretion.

RESULTS

Expression of the autophagy proteins Beclin-1, Atg3, Atg5, Atg7, Atg12, Atg16L1 were lower after spontaneous term labour. Beclin-1 and Atg7 expression were lower after spontaneous preterm labour. Beclin-1, Atg3, and Atg7 expression were lower after preterm pre-labour rupture of membranes (PPROM) compared to preterm with intact membranes. LC3B-I expression was higher after spontaneous term and preterm labour and with PPROM; there was no difference in LC3B-II expression between the two groups. The autophagy inhibitor LY290042 increased IL-1β secretion in the presence of bacterial endotoxin LPS; IL-1β secretion was ameliorated in the presence inflammasome inhibitors.

DISCUSSION

Autophagy is decreased in fetal membranes after spontaneous labour and delivery, and PPROM. Inhibition of autophagy regulates the secretion of IL-1β via inflammasome activation. IL-1β is a major contributor to the pathophysiology of spontaneous preterm birth. Therefore activation of autophagy may be a potential therapeutic mechanism to delay or prevent infection-induced preterm birth.

Inhibition of autophagy in peripheral blood mononuclear cells by vaginal fluid from women with a malignant adnexal mass

Inhibition of autophagy is a characteristic of ovarian cancer. We determined whether inhibition of autophagy by vaginal fluid could provide a non-invasive test for cancer risk stratification in women presenting with an adnexal mass. Vaginal fluid supernatants from 90 women undergoing evaluation for a suspicious adnexal mass were incubated with peripheral blood mononuclear cells (PBMCs) obtained from healthy women under conditions that induce autophagy. Rapamycin, an autophagy inducer, was added to some cultures. After 48 hr the cells were collected, lysed and assayed by ELISA for intracellular p62 concentration. p62 is a cytoplasmic protein that is consumed during autophagy induction. Its concentration is inversely proportional to the extent of autophagy induction. Clinical information including pathological diagnoses was obtained after completion of laboratory studies. Mean p62 levels were 9.4 ng/ml in the 21 women with a subsequent malignant diagnosis, 4.5 ng/ml in the eight women with a borderline tumor diagnosis and 3.6 ng/ml in the 61 women with benign disease (p < 0.0001, malignant vs. others). When rapamycin was added to the vaginal fluid-PBMC co-incubation, p62 levels in samples from women with a malignant diagnosis decreased to 3.3 ng/ml, a level comparable to what was observed with the nonmalignant samples. Vaginal fluid inhibition of autophagy can differentiate between women with malignant and benign adnexal masses.

Induction of the 70 kDa heat shock protein stress response inhibits autophagy: possible consequences for pregnancy outcome

AIM

The induction of heat shock protein synthesis and activation of autophagy are intracellular processes stimulated under adverse conditions. We evaluated the relationship between intracellular concentrations of the inducible 70 kDa heat shock protein (hsp70) and autophagy induction in human peripheral blood mononuclear cells (PBMCs) following exposure to sera from pregnant and non-pregnant women.

METHODS

Autophagy was induced in PBMCs by incubation for 48 h with sera from 42 pregnant women at mid-gestation and 45 non-pregnant women. Intracellular concentrations of hsp70 and p62 were measured by ELISA. p62 is a cytoplasmic protein that is consumed during autophagy induction. Its concentration in the cytoplasm is inversely proportional to the extent of autophagy induction (high p62 = low autophagy).

RESULTS

The p62 concentration was highly correlated with the hsp70 level utilizing sera from both pregnant (Spearman r = 0.4731, p = 0.0015) and non-pregnant (Spearman r = 0.6214, p < 0.0001) women. Median p62 (7.4 ng/ml versus 2.7 ng/ml, p < 0.0001) and hsp70 (7.0 ng/ml versus 3.5 ng/ml, p = 0.0022) levels were higher when PBMCS were incubated with sera from pregnant women.

CONCLUSION

The extent of autophagy in PBMCs is inversely proportional to the intracellular hsp70 concentration and sera from pregnant women induces hsp70 and inhibits autophagy to a greater extent than does sera from non-pregnant women. A stress response that induces hsp70 has the potential to interfere with autophagy-related events.

Microorganisms in the female genital tract during pregnancy: tolerance versus pathogenesis

Microorganisms in the pregnant female genital tract are not always associated with pathology. The factors that influence the maternal response to microorganisms remain ill defined. We review the state of knowledge of microbe-host interactions in gestational tissues and highlight mechanisms that promote tolerance or pathogenesis. Tolerance to microorganisms is promoted during pregnancy by several mechanisms including upregulation of anti-inflammatory mediators, induction of endotoxin tolerance, and possibly by regulation of autophagy. Conversely, an altered vaginal microbiota or a pre-existing viral presence may result in induction of excessive inflammation and preterm labor. Although infections play a prevalent role in preterm birth, microbes are present in gestational tissues of women with healthy outcomes and may provide beneficial functions. The complex interactions between different microbial species and the maternal immune system during gestation remain incompletely elucidated.

Altered autophagy induction by sera from pregnant women with pre-eclampsia: a case-control study

OBJECTIVE

Mechanisms leading to pre-eclampsia remain incompletely defined. Autophagy is a conserved process necessary for cell survival under adverse conditions. We hypothesised that sera from women with healthy pregnancies and women with pre-eclampsia differed in autophagy induction.

DESIGN

A case-control study.

SETTING

Weill Cornell Medical College.

POPULATION

Twenty-four normotensive pregnant women and 20 women with pre-eclampsia.

METHODS

Sera were incubated with peripheral blood mononuclear cells (PBMCs) from female donors. After 48 hours the PBMCs were lysed and the intracellular concentration of p62 was determined by enzyme-linked immunosorbent assay (ELISA). Its concentration is inversely proportional to the extent of autophagy induction. Serum endoglin, interleukin 13 (IL-13), insulin-like growth factor 1 (IGF-1), and transforming growth factor β1 (TGF-β1) levels were quantitated by ELISA.

MAIN OUTCOME MEASURES

Differences in autophagy induction and serum mediator levels in the two groups.

RESULTS

Autophagy induction increased with gestational age in sera from normotensive women (P = 0.0045), but not in women with pre-eclampsia. In the presence of an autophagy inducer, the capacity for autophagy induction decreased with gestational age in sera from women with pre-eclampsia (P = 0.0235), but not from controls. Endoglin concentrations were positively associated with the extent of autophagy induction in controls only (P = 0.0141). There was no association between autophagy and serum IL-13, IGF-1, or TGF-β1 levels.

CONCLUSIONS

Sera from women with pre-eclampsia differ from normotensive women by their inability to induce autophagy as a function of gestational age.

The role of autophagy in reproduction from gametogenesis to parturition

Autophagy is an intracellular process responsible for maintaining cellular homeostasis by the removal of cytoplasmic organelles, intracellular bacteria and viruses, and is a critical component of both the innate and acquired immune systems. A failure in physiological activation, assembly and function of the autophagic pathway has been implicated in a broad range of diseases including neurogenerative diseases, cardiopathy, infectious diseases, autoimmunity and cancer. Its involvement in reproduction, however, has not been extensively studied. Its activity is fundamental to many processes across the reproduction spectrum from development of the primordial follicle and spermatozoa to embryogenesis, placental development and maintaining uterine quiescence during pregnancy. Malfunctions in autophagy are associated with deleterious repercussions throughout reproduction. In this review we examine what is known about the involvement of autophagy in gamete formation, early post-fertilization embryogenesis, placental development and parturition, and propose promising areas for future research.