Aberrant retinoic acid production in the decidua: Implications for pre-eclampsia

Insights into preeclampsia: a bioinformatics approach to deciphering genetic and immune contributions

Background

Preeclampsia (PE) is a global pregnancy concern, characterized by hypertension with an unclear etiology. This study employs Mendelian randomization (MR) and single-cell RNA sequencing (scRNA-seq) to clarify its genetic and molecular roots, offering insights into diagnosis and treatment avenues.

Methods

We integrated PE-specific genome-wide association study (GWAS) data, expression and protein quantitative trait loci (eQTL and pQTL) data, and single-cell data from peripheral blood mononuclear cells (PBMCs). We identified highly variable genes using single-cell information and employed MR to determine potential causality. We also combined pQTL and GWAS data, discerned genes positively associated with PE through scRNA-seq, and leveraged the Enrichr platform to unearth drug-gene interactions.

Results

Our scRNA-seq pinpointed notable cell type distribution variances, especially in T helper cells (Th cells), between PE and control groups. We unveiled 591 highly variable genes and 6 directly PE-associated genes. Although MR revealed correlations with PE risk, pQTL analysis was inconclusive due to data constraints. Using DSigDB, 93 potential therapeutic agents, like Retinoic acid targeting core genes (IFITM3, NINJ1, COTL1, CD69, and YWHAZ), emerged as prospective multi-target treatments.

Conclusion

Utilizing MR and scRNA-seq, this study underscores significant cellular disparities, particularly in Th cells, and identifies crucial genes related to PE. Despite some limitations, these genes have been revealed in PE's underlying mechanism. Potential therapeutic agents, such as Retinoic acid, suggest promising treatment pathways.

Inhibitory effect of all-trans retinoic acid on ferroptosis in BeWo cells mediated by the upregulation of heme Oxygenase-1

INTRODUCTION

This study aimed to explore the association between ferroptosis, a newly identified type of cell death, and the role of retinoic acid in developing pregnancy complications. Therefore, the effects of all-trans retinoic acid (ATRA) on ferroptosis susceptibility in BeWo cells were assessed to understand abnormal placental development.

METHODS

BeWo cells were used as surrogates for cytotrophoblasts. The effect of ATRA on ferroptosis sensitivity was assessed on BeWo cells pretreated with ATRA or dimethyl sulfoxide (DMSO; control), following which the LDH-releasing assay was performed. The effects of ATRA pretreatment on the antioxidant defense system (including glutathione [GSH], mitochondrial membrane potential, and heme oxygenase-1 [HMOX1]) in BeWo cells were assessed using assay kits, RT-qPCR, and HMOX1 immunostaining. To evaluate the effect of ATRA on BeWo cells, HMOX1 was silenced in BeWo cells using shRNA.

RESULTS

ATRA pretreatment increased ferroptosis resistance in BeWo cells. Although with pretreatment, qPCR indicated upregulation of HMOX1, no significant change was observed in the GSH levels or mitochondrial membrane potential. This was corroborated by intensified immunostaining for heme oxygenase-1 protein (HO-1). Notably, the protective effect of ATRA against ferroptosis was negated when HO-1 was inhibited. Although HMOX1-silenced BeWo cells exhibited heightened ferroptosis sensitivity compared with controls, ATRA pretreatment counteracted ferroptosis in these cells.

DISCUSSION

ATRA pretreatment promotes BeWo cell viability by suppressing ferroptosis and upregulating HMOX1 and this can be used as a potential therapeutic strategy for addressing placental complications associated with ferroptosis.

Retinoic Acid-PPARα Mediates β-Carotene Resistance to Placental Dysfunction Induced by Deoxynivalenol

Deoxynivalenol (DON), one of the most polluted mycotoxins in the environment and food, has been proven to have strong embryonic and reproductive toxicities. However, the effects of DON on placental impairment and effective interventions are still unclear. This study investigated the effect of β-carotene on placental functional impairment and its underlying molecular mechanism under DON exposure. Adverse pregnancy outcomes were caused by intraperitoneal injection of DON from 13.5 to 15.5 days of gestation in mice, resulting in higher enrichment of DON in placenta than in other tissue samples. Interestingly, 0.1% β-carotene dietary supplementation could significantly alleviate DON-induced pregnancy outcomes. Additionally, in vivo and in vitro placental barrier models demonstrated the association of DON-induced placental function impairment with placental permeability barrier disruption, angiogenesis impairment, and oxidative stress induction. Moreover, β-carotene regulated DON-induced placental toxicity by activating the expressions of claudin 1, zonula occludens-1, and vascular endothelial growth factor-A through retinoic acid-peroxisome proliferator-activated receptor α signaling.

Decidual dendritic cells 10 and CD4+CD25+FOXP3 regulatory T cell in preeclampsia and their correlation with nutritional factors in pathomechanism of immune rejection in pregnancy

BACKGROUND

Immune intolerance is thought to be the underlying cause of immune rejection to fetus in preeclampsia. Decidual dendritic cell-10 (DC-10) and T regulator cell (Treg) play important role to create tolerogenic environment during pregnancy. However, their roles on the specific pathomechanism of preeclampsia along with various nutritional factors have not been widely studied.

AIM

To determine the number of DC-10 and Treg in preeclampsia and their correlations with decidual nutritional factors.

METHOD

This was a cross-sectional study among early onset preeclampsia (EOPE), late onset preeclampsia (LOPE), and normotensive (NT) pregnancies. Decidual specimens were obtained by curettage after caesarean section. The number of DC-10 and Treg cells were counted using flow cytometry. The levels of nutritional factors (zinc, retinol, all-trans retinoic acid, vitamin D) were determined using ICP-MS and LC-MS method.

RESULT

A total of 14 subjects for each group were included in the study. The DC-10 was significantly lower in both EOPE and LOPE compared to NT (p < 0.001). Treg cells were significantly higher in EOPE compare to NT (p = 0.015). There was a moderate correlation between zinc level and DC-10 (p = 0.011) and a strong correlation between retinol level and DC-10 (p = 0.002) in the NT group. A moderate correlation was found between vitamin D level and Treg cells in the NT group (p = 0.026).

CONCLUSION

There was a lower number of DC-10 and higher number of Treg cells in early preeclampsia. There was no correlation between DC-10 and Treg number with decidual nutritional factors in preeclampsia.