Functional analysis of HSPA1A and HSPA8 in parturition

Identification of potential differences in salivary proteomic profiles between estrus and diestrus stage of estrous cycle in dairy cows

In the present study, a comparative global high-throughput proteomic analysis strategy was used to identify proteomic differences between estrus and diestrus stage of estrous cycle in dairy cows. Saliva was collected from cows during estrus and diestrus, and subjected to LC-MS/MS-based proteomic analysis. A total of 2842 proteins were detected in the saliva of cows, out of which, 2437 and 1428 non-redundant proteins were identified in estrous and diestrous saliva, respectively. Further, it was found that 1414 and 405 salivary proteins were specific to estrus and diestrus, respectively while 1023 proteins were common to both groups. Among the significantly dysregulated proteins, the expression of 56 proteins was down-regulated (abundance ratio <0.5) while 40 proteins were up-regulated (abundance ratio > 2) in estrous compared to diestrous saliva. The proteins, such as HSD17B12, INHBA, HSP70, ENO1, SRD5A1, MOS, AMH, ECE2, PDGFA, OPRK1, SYN1, CCNC, PLIN5, CETN1, AKR1C4, NMNAT1, CYP2E1, and CYP19A1 were detected only in the saliva samples derived from estrous cows. Considerable number of proteins detected in the saliva of estrous cows were found to be involved in metabolic pathway, PI3K-Akt signaling pathway, toll-like receptor signaling pathway, steroid biosynthesis pathway, insulin signaling pathway, calcium signaling pathway, estrogen signaling pathway, oxytocin signaling pathway, TGF-β signaling pathway and oocyte meiosis. On the other hand, proteins detected in saliva of diestrous cows were involved mainly in metabolic pathway. Collectively, these data provide preliminary evidence of a potential difference in salivary proteins at different stages of estrous cycle in dairy cows.

Effect of oxidative stress induced by 2,3,7,8- tetrachlorodibenzo-p-dioxin on DNA damage

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a highly toxic persistent organic pollutant (POP) that can induce DNA damage within cells. Although oxidative stress is one of the primary mechanisms causing DNA damage, its role in the process of TCDD-induced DNA damage remains unclear. In this study, the TCDD-induced production of reactive oxygen species (ROS) and the occurrence of DNA damage at the AP site were monitored simultaneously. Further investigation revealed that TCDD impaired the activities of superoxide dismutase (SOD) and catalase (CAT), compromising the cellular antioxidant defense system. Consequently, this led to an increase in the production of O2.- and NO, thus inducing DNA damage at the AP site under oxidative stress. Our findings were further substantiated by the upregulation of key genes in the base excision repair (BER) pathway and the absence of DNA AP site damage after inhibiting O2.- and NO. In addition, transcriptome sequencing revealed that TCDD induces DNA damage by upregulating genes associated with oxidative stress in the mitogen-activated protein kinase (MAPK), cyclic adenosine monophosphate (cAMP), and breast cancer pathways. This study provides important insights into the toxicity mechanisms of TCDD.

Elevated human placental heat shock protein 5 is associated with spontaneous preterm birth

BACKGROUND

Specific heat shock proteins are associated with pregnancy complications, including spontaneous preterm birth (SPTB). Placental proteomics and whole exome sequencing recently suggested an association between heat shock protein HSPA5 and uncomplicated SPTB. In the present study, we investigated the localization of and possible roles for HSPA5 in SPTB.

METHODS

Western blot was performed to validate the result from the previously published proteomic analysis. We used qPCR to assess mRNA expression of genes and immunohistochemistry and immunoelectron microscopy to examine localization of HSPA5 in placental tissue. We silenced the HSPA5 gene in the HTR8/SVneo human trophoblast cell line to investigate possible functions of HSPA5.

RESULTS

HSPA5 was upregulated in placentas from SPTBs compared to spontaneous term births. We did not observe upregulation of HSPA5 mRNA in placental samples. The protein was localized in placental trophoblast in both spontaneous preterm and term placentas. Gene silencing of HSPA5 in human trophoblast cell culture affected the inflammatory response and decreased the expression of several proinflammatory genes.

CONCLUSIONS

We suggest that upregulation of HSPA5 in the placenta is associated with spontaneous preterm labor. HSPA5 may promote the inflammatory response and alter the anti-inflammatory state of the placenta which could eventually lead to premature labor.

IMPACT

We validated upregulation of HSPA5 in placentas from spontaneous preterm birth. HSPA5 was not upregulated at transcriptional level which suggests that it may be regulated post-translationally. Silencing HSPA5 in a human trophoblast-derived cell line suggested that HSPA5 promotes expression of proinflammatory cytokines. The emerging inflammation could lead to spontaneous preterm labor. Identifying inflammatory pathways and factors associated with spontaneous preterm birth increases knowledge of the molecular mechanisms of premature labor. This could provide cues to predict imminent premature labor and lead to information about how to safely maintain pregnancies.

Effect of Low-Frequency Electrical Stimulation Combined with Tonifying Kidney and Blood Pills on Uterine Rejuvenation after Abortion

Objective

This study aimed to observe the clinical efficacy of low-frequency electrical stimulation therapy combined with tonifying the kidney and activating blood pills to promote uterine recovery after abortion and its effect on heat-shock protein (HSP)70 and HSP90.

Methods

All cases were women with early pregnancy who underwent an abortion at the Third Affiliated Hospital of Nanchang University from September 2019 to September 2020. They were divided into two groups in accordance with the principle of patient voluntariness: 237 cases in the experimental group and 143 cases in the control group. Patients in both groups were given low-frequency electrical stimulation after surgery. In addition, patients in the experimental group began to take the Dingkun pill orally (one pill per time, two times per day) from the first day of surgery and continued to take it until their menstruation returned to normal. Abdominal pain, the duration of vaginal bleeding, and the amount of bleeding were observed in both groups. Uterine size, endometrial thickness, and urinary human chorionic gonadotropin (HCG) status were also observed at 2 weeks postoperatively to determine preoperative and postoperative HSP70 and HSP90 serum levels. The time of menstrual resumption, menstrual period, and menstrual volume were observed and compared with preoperative menstruation. The occurrence of complications, such as a residual uterine cavity, uterine effusion, menstrual irregularities, and reproductive tract infections, during the follow-up period was also recorded in both groups.

Results

Comparison of the endometrial thickness (mm) and uterine size (sum of the three diameters) on uterine adnexal ultrasound at 2-week postoperative review was better in the experimental group than in the control group (p < 0.05). No statistically significant difference was found between the two groups in terms of residual uterine cavity and blood accumulation in the uterine cavity and the results of the urine pregnancy test (p > 0.05). Serum HSP70 and HSP90 levels were significantly higher in the control group than in the experimental group 2 weeks after surgery (p < 0.05). Postoperative HSP70 and HSP90 levels were significantly higher than preoperative levels in both groups (p < 0.05). The degree of postoperative abdominal pain in the experimental group was less severe than that in the control group, and the duration was shorter (p < 0.05). No statistically significant differences were observed when comparing the duration of postoperative vaginal bleeding and the amount of bleeding (p > 0.05). The time of the first menstrual resumption and menstrual volume were more satisfactory in the experimental group than in the control group (p < 0.05). No adverse reactions occurred in either group of patients receiving treatment.

Conclusion

Low-frequency electrical stimulation combined with tonifying the kidney and invigorating blood pills could effectively promote uterine rejuvenation after abortion, conducive to improving patients' postoperative abdominal pain, promoting menstrual recovery and maintaining menstrual flow.

Maternal respiratory SARS-CoV-2 infection in pregnancy is associated with a robust inflammatory response at the maternal-fetal interface

BACKGROUND

Pregnant women are at increased risk for severe outcomes from coronavirus disease 2019 (COVID-19), but the pathophysiology underlying this increased morbidity and its potential effect on the developing fetus is not well understood.

METHODS

We assessed placental histology, ACE2 expression, and viral and immune dynamics at the term placenta in pregnant women with and without respiratory severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

FINDINGS

The majority (13 of 15) of placentas analyzed had no detectable viral RNA. ACE2 was detected by immunohistochemistry in syncytiotrophoblast cells of the normal placenta during early pregnancy but was rarely seen in healthy placentas at full term, suggesting that low ACE2 expression may protect the term placenta from viral infection. Using immortalized cell lines and primary isolated placental cells, we found that cytotrophoblasts, the trophoblast stem cells and precursors to syncytiotrophoblasts, rather than syncytiotrophoblasts or Hofbauer cells, are most vulnerable to SARS-CoV-2 infection in vitro. To better understand potential immune mechanisms shielding placental cells from infection in vivo, we performed bulk and single-cell transcriptomics analyses and found that the maternal-fetal interface of SARS-CoV-2-infected women exhibited robust immune responses, including increased activation of natural killer (NK) and T cells, increased expression of interferon-related genes, as well as markers associated with pregnancy complications such as preeclampsia.

CONCLUSIONS

SARS-CoV-2 infection in late pregnancy is associated with immune activation at the maternal-fetal interface even in the absence of detectable local viral invasion.

FUNDING

NIH (T32GM007205, F30HD093350, K23MH118999, R01AI157488, U01DA040588) and Fast Grant funding support from Emergent Ventures at the Mercatus Center.

Inducible heat shock protein A1A (HSPA1A) is markedly expressed in rat myometrium by labour and secreted via myometrial cell-derived extracellular vesicles

The myometrium goes through physiological, cellular and molecular alterations during gestation that necessitate effective cellular proteostasis. Inducible heat shock protein A1A (HSPA1A) is a member of the 70-kDa heat shock protein A (HSPA) family, which acts as a chaperone to regulate proteostasis; however, HSPA1A also participates as a cytokine in inflammatory regulation, leading to its designation as a chaperokine. This study examined the spatiotemporal expression of HSPA1A protein in the rat myometrium throughout gestation and assessed whether it is secreted as cargo of myometrial cell-derived extracellular vesicles (EVs). Immunoblot analysis demonstrated that HSPA1A expression was markedly elevated during late pregnancy and labour and increased by uterine distension. Myometrial HSPA1A expression insitu increased in myocytes of longitudinal and circular muscle layers from Day 19 through to postpartum, specifically in the cytoplasm and nuclei of myocytes from both muscle layers, but frequently detectable just outside myocyte membranes. Scanning electron microscopy examination of samples isolated from hTERT-HM cell-conditioned culture medium, using EV isolation spin columns, confirmed the presence of EVs. EV lysates contained HSPA8, HSPA1A and the EV markers apoptosis-linked gene 2-interacting protein X (Alix), the tetraspanin cluster of differentiation 63 (CD63), tumour susceptibility gene 101 (TSG101) and HSP90, but not the endoplasmic reticulum protein calnexin. These results indicate that HSPA1A may act as a chaperokine in the myometrium during pregnancy.

SARS-CoV-2 infection in pregnancy is associated with robust inflammatory response at the maternal-fetal interface

Pregnant women appear to be at increased risk for severe outcomes associated with COVID-19, but the pathophysiology underlying this increased morbidity and its potential impact on the developing fetus is not well understood. In this study of pregnant women with and without COVID-19, we assessed viral and immune dynamics at the placenta during maternal SARS-CoV-2 infection. Amongst uninfected women, ACE2 was detected by immunohistochemistry in syncytiotrophoblast cells of the normal placenta during early pregnancy but was rarely seen in healthy placentas at full term. Term placentas from women infected with SARS-CoV-2, however, displayed a significant increase in ACE2 levels. Using immortalized cell lines and primary isolated placental cells, we determined the vulnerability of various placental cell types to direct infection by SARS-CoV-2 in vitro. Yet, despite the susceptibility of placental cells to SARS-CoV-2 infection, viral RNA was detected in the placentas of only a subset (~13%) of women in this cohort. Through single cell transcriptomic analyses, we found that the maternal-fetal interface of SARS-CoV-2-infected women exhibited markers associated with pregnancy complications, such as preeclampsia, and robust immune responses, including increased activation of placental NK and T cells and increased expression of interferon-related genes. Overall, this study suggests that SARS-CoV-2 is associated with immune activation at the maternal-fetal interface even in the absence of detectable local viral invasion. While this likely represents a protective mechanism shielding the placenta from infection, inflammatory changes in the placenta may also contribute to poor pregnancy outcomes and thus warrant further investigation.

Natural Mating Differentially Triggers Expression of Glucocorticoid Receptor (NR3C1)-Related Genes in the Preovulatory Porcine Female Reproductive Tract

Mating initiates dynamic modifications of gene transcription in the female reproductive tract, preparing the female for fertilization and pregnancy. Glucocorticoid signaling is essential for the homeostasis of mammalian physiological functions. This complex glucocorticoid regulation is mediated through the glucocorticoid receptor, also known as nuclear receptor subfamily 3 group C member 1 (NR3C1/GR) and related genes, like 11β-hydroxysteroid dehydrogenases (HSD11Bs) and the FK506-binding immunophilins, FKBP5 and FKBP4. This study tested the transcriptome changes in NR3C1/GR regulation in response to natural mating and/or cervical deposition of the sperm-peak ejaculate fraction collected using the gloved-hand method (semen or only its seminal plasma), in the preovulatory pig reproductive tract (cervix to infundibulum, 24 h after mating/insemination/infusion treatments). Porcine cDNA microarrays revealed 22 NR3C1-related transcripts, and changes in gene expression were triggered by all treatments, with natural mating showing the largest differences, including NR3C1, FKBP5, FKBP4, hydroxysteroid 11-beta dehydrogenase 1 and 2 (HSD11B1, HSD11B2), and the signal transducer and activator of transcription 5A (STAT5A). Our data suggest that natural mating induces expression changes that might promote a reduction of the cortisol action in the oviductal sperm reservoir. Together with the STAT-mediated downregulation of cytokine immune actions, this reduction may prevent harmful effects by promoting tolerance towards the spermatozoa stored in the oviduct and perhaps elicit spermatozoa activation and detachment after ovulation.

Alarmins at the maternal-fetal interface: involvement of inflammation in placental dysfunction and pregnancy complications 1

Inflammation is known to be associated with placental dysfunction and pregnancy complications. Infections are well known to be a cause of inflammation but they are frequently undetectable in pregnancy complications. More recently, the focus has been extended to inflammation of noninfectious origin, namely caused by endogenous mediators known as "damage-associated molecular patterns (DAMPs)" or alarmins. In this manuscript, we review the mechanism by which inflammation, sterile or infectious, can alter the placenta and its function. We discuss some classical DAMPs, such as uric acid, high mobility group box 1 (HMGB1), cell-free fetal deoxyribonucleic acid (DNA) (cffDNA), S100 proteins, heat shock protein 70 (HSP70), and adenosine triphosphate (ATP) and their impact on the placenta. We focus on the main placental cells (i.e., trophoblast and Hofbauer cells) and describe the placental response to, and release of, DAMPs. We also covered the current state of knowledge about the role of DAMPs in pregnancy complications including preeclampsia, fetal growth restriction, preterm birth, and stillbirth and possible therapeutic strategies to preserve placental function.

Co-expression of RelA/p65 and ACTN4 induces apoptosis in non-small lung carcinoma cells

Alpha-actinin 4 (ACTN4) is an actin-binding protein of the spectrin superfamily. ACTN4 is found both in the cytoplasm and nucleus of eukaryotic cells. The main function of cytoplasmic ACTN4 is stabilization of actin filaments and their binding to focal contacts. Nuclear ACTN4 takes part in the regulation of gene expression following by activation of certain transcription factors, but the mechanisms of regulation are not completely understood. Our previous studies have demonstrated the interaction of ACTN4 with the RelA/p65 subunit of NF-kappaB factor and the effect on its transcriptional activity in A431 and HEK293T cells. In the present work, we investigated changes in the composition of nuclear ACTN4-interacting proteins in non-small cell lung cancer cells H1299 upon stable RELA overexpression. We showed that ACTN4 was present in the nuclei of H1299 cells, regardless of the RELA expression level. The presence of ectopic RelA/p65 in H1299 cells increased the number of proteins interacting with nuclear ACTN4. Stable expression of RELA in these cells suppressed cell proliferation, which was further affected by simultaneous ACTN4 overexpression. We detected no significant effect on cell cycle but the apoptosis rate was increased in cells with a double RELA/ACTN4 overexpression. Interestingly, when expressed individually ACTN4 promoted proliferation of lung cancer cells. Furthermore, the bioinformatics analysis of gene expression in lung cancer patients suggested that overexpression of ACTN4 correlated with poor survival prognosis. We hypothesize that the effect of RELA on proliferation and apoptosis of H1299 cells can be mediated via affecting the interactome of ACTN4.