Double hit of NEMO gene in preeclampsia

The NFκB Signaling Pathway Is Involved in the Pathophysiological Process of Preeclampsia

The high prevalence of preeclampsia (PE) is a major cause of maternal and fetal mortality and affects the long-term prognosis of both mother and baby. Termination of pregnancy is currently the only effective treatment for PE, so there is an urgent need for research into its pathogenesis and the development of new therapeutic approaches. The NFκB family of transcription factors has an essential role in inflammation and innate immunity. In this review, we summarize the role of NFκB in normal and preeclampsia pregnancies, the role of NFκB in existing treatment strategies, and potential NFκB treatment strategies.

PAD4 silencing inhibits inflammation whilst promoting trophoblast cell invasion and migration by inactivating the NEMO/NF‑κB pathway

Preeclampsia (PE), presenting with onset hypertension and proteinuria, is a pregnancy-specific disorder that can result in maternal and fetal morbidity and mortality. Insufficient trophoblast invasion and migration has been considered to be an important cause of this disease. The present study aimed to investigate the role of peptidyl arginine deiminase 4 (PAD4), whose knockdown has been previously indicated to reduce inflammation and susceptibility to pregnancy loss in mice, in the development of PE in vitro. Lipopolysaccharide (LPS) was used to treat a human trophoblast cell line (HTR8/SVneo). After PAD4 silencing via transfection with short hairpin RNA against PAD4, the concentrations of inflammatory factors IL-6, IL-12 and monocyte chemoattractant protein (MCP)-1 were measured using ELISA. Cell viability was also measured using Cell Counting Kit-8 assay. HTR8/SVneo cell invasion and migration were detected using Transwell and wound healing assays, respectively. Western blotting was used to measure the expression of citrullinated NF-κB essential modulator (NEMO) and nuclear NF-κB p65 protein levels. TNF-α was applied for evaluating the potential regulatory effects of PAD4 on NF-κB in LPS-stimulated HTR8/SVneo cells. LPS increased the levels of IL-6, IL-12 and MCP-1 and reduced the migration and invasion of HTR8/SVneo cells. PAD4-knockdown was found to markedly reduce the levels of IL-6, IL-12 and MCP-1 secretion. HTR8/SVneo cell invasion and migration was also significantly elevated after PAD4 silencing following LPS exposure. In addition, LPS stimulation notably upregulated the protein levels of citrullinated NEMO and nuclear NF-κB p65, which was restored by PAD4 knockdown. Furthermore, TNF-α treatment partially counteracted the effects of PAD4 knockdown on the secretion of IL-6, MCP-1 and IL-12, which are markers of inflammation, and invasion and migration in LPS-induced HTR8/SVneo cells. To conclude, these results suggest that PAD4 silencing can suppress inflammation whilst promoting invasion and migration by trophoblast cells through inhibiting the NEMO/NF-κB pathway. These findings furthered the understanding in the complex molecular mechanism that can trigger PE and provide a promising target for the treatment of this disease.

Expression of lncRNA TINCR in the placenta of patients with pre-eclampsia and its effect on the biological behaviours of trophoblasts

To explore the effect of lncRNA TINCR on the biological behaviours of trophoblasts, we detected and analyzed the expression of terminal differentiation-induced non-protein coding RNA (TINCR) in the placenta tissues of pre-eclamptic and non-pre-eclamptic pregnant women. The gain- and loss-of-function of TINCR was performed to examine the proliferation, migration and invasion abilities of Htr-8/Svneo cells. The levels of epithelial-mesenchymal transition (EMT)-related proteins, cyclin and Wnt/β-catenin pathway were detected. High expression of lncRNA TINCR appeared in placental tissues of patients with pre-eclampsia. The proliferation, invasion and migration of Htr-8/Svneo cells were promoted by TINCR downregulation; the cells were transited from G0/G1 to S phase; and EMT was promoted and the Wnt/β-catenin pathway was activated. In summary, the downregulation of lncRNA TINCR activated the Wnt/β-catenin pathway and promoted the proliferation, invasion and migration of Htr-8/Svneo cells. This study may provide a theoretical basis for treatment of patients with pre-eclampsia.

The Role of NF-κB in Uterine Spiral Arteries Remodeling, Insight into the Cornerstone of Preeclampsia

Preeclampsia is one of the three leading causes of maternal morbidity and mortality worldwide. It afflicts 2-8% of pregnancies and is the most common cause of gestational hypertension. This article is focused on nuclear factor kappa B (NF-κB), its role in normal and pathological spiral arteries remodelling and development of preeclampsia, with evaluation if it is a promising therapeutic target. NF-κB is a key mediator of placentation. Since insemination, it stimulates production of proinflammatory cytokines by the uterine epithelium, which leads to activation of macrophages, uterine natural killer cells (uNKs), and other leukocytes. The trophoblast/uNK/macrophage crosstalk is crucial for implantation and spiral arteries remodeling, and NF-κB regulates that process through modification of cytokine expression, as well as cell phenotype and function. In the course of preeclampsia, the remodeling processes is disturbed by excessive inflammation and increased NF-κB activation. The pathological remodeling leads to uteroplacental dysfunction, release of proinflammatory cytokines into the maternal circulation, endothelial stress, and development of preeclampsia. The analysis of genetic and environmental inductors of NF-κB helps to distinguish preeclampsia risk groups. Furthermore, a selective inhibition of NF-κB or NF-κB activating pathways alleviates symptoms of preeclampsia in rat models; therefore, this could be an efficient therapeutic option.

Analysis of IKBKG/NEMO gene in five Japanese cases of incontinentia pigmenti with retinopathy: fine genomic assay of a rare male case with mosaicism

Incontinentia pigmenti (IP) is an X-linked dominant genodermatosis that is usually lethal in utero in males, though exceptionally they survive very rarely either with Klinefelter syndrome or a somatic mosaicism. We performed genomic analysis of five Japanese IP patients including a rare boy case, all of whom were definite cases with retinopathy. Four patients including the boy revealed the recurrent exon 4-10 deletion in the sole known causative gene IKBKG/NEMO, which was confirmed by various specific PCR techniques. The boy's saliva DNA showed a mosaicism consisting of the deletion and intact alleles, but his blood DNA did not. Relative quantification analysis of the real-time PCR data by ∆∆CT method estimated the mosaicism ratio of the boy's saliva as 45:55 (deletion:intact). A genomic analysis for the recurrent deletion at the nucleotide sequence level has been performed directly using patient's DNA and it has been clarified that the breakpoints are within two MER67B repeats in the intron 3 and downstream of exon 10. This is the first report of the assay for the mosaicism ratio of a male IP case with a recurrent exon 4-10 deletion of IKBKG/NEMO and the sequencing analysis of the breakpoints of the recurrent deletion directly using patient's sample.

Questionnaire survey on association between preeclampsia and incontinentia pigmenti

AIM

In this study, a questionnaire survey was conducted to find the relationship between preeclampsia (PE) and incontinentia pigmenti (IP).

METHODS

Using a questionnaire survey of 147 women whose children were diagnosed with IP, this study first investigated their clinical manifestations and complications during pregnancy. The manifestations included high blood pressure, proteinuria and edema after 20 weeks of gestation. Women with and without IP were separated into two groups, then analyzed accordingly.

RESULTS

There were 45 mothers with IP in the case group and 102 mothers without IP in the control group. IP mothers who were pregnant with an IP fetus were at higher risk for hypertension, proteinuria, and edema during pregnancy as compared with non-IP mothers that carried an IP fetus. Out of these 147 mothers, 8 mothers with IP and 6 mothers without IP presented with new-onset hypertension during pregnancy (P = 0.024)，7 mothers with IP and 4 mothers without IP presented with new-onset proteinuria during pregnancy (P = 0.013)，and 21 IP mothers and 27 non-IP mothers presented with edema during pregnancy (P = 0.016). Although no statistical difference was observed, mothers in the case group were more likely to develop the above three symptoms concurrently (6.7% vs 2.0%; P = 0.168), and were more likely to be diagnosed with PE (8.9% vs 3.9%; P = 0.249).

CONCLUSION

Our study revealed that the simultaneous occurrence of IP in the mother and fetus increased the likelihood of clinical manifestations associated with PE during pregnancy.