Expression and Functional Analysis of CXCL12 and Its Receptors in Human Term Trophoblast Cells

Pathophysiological impact of CXC and CX3CL1 chemokines in preeclampsia and gestational diabetes mellitus

Diabetes-related pathophysiological alterations and various female reproductive difficulties were common in pregnant women with gestational diabetes mellitus (GDM), who had 21.1 million live births. Preeclampsia (PE), which increases maternal and fetal morbidity and mortality, affects approximately 3%-5% of pregnancies worldwide. Nevertheless, it is unclear what triggers PE and GDM to develop. Therefore, the development of novel moderator therapy approaches is a crucial advancement. Chemokines regulate physiological defenses and maternal-fetal interaction during healthy and disturbed pregnancies. Chemokines regulate immunity, stem cell trafficking, anti-angiogenesis, and cell attraction. CXC chemokines are usually inflammatory and contribute to numerous reproductive disorders. Fractalkine (CX3CL1) may be membrane-bound or soluble. CX3CL1 aids cell survival during homeostasis and inflammation. Evidence reveals that CXC and CX3CL1 chemokines and their receptors have been the focus of therapeutic discoveries for clinical intervention due to their considerable participation in numerous biological processes. This review aims to give an overview of the functions of CXC and CX3CL1 chemokines and their receptors in the pathophysiology of PE and GDM. Finally, we examined stimulus specificity for CXC and CX3CL1 chemokine expression and synthesis in PE and GDM and preclinical and clinical trials of CXC-based PE and GDM therapies.

Regulation and Function of Chemokines at the Maternal–Fetal Interface

Successful pregnancy requires the maternal immune system to tolerate the semi-allogeneic embryo. A good trophoblast function is also essential for successful embryo implantation and subsequent placental development. Chemokines are initially described in recruiting leukocytes. There are rich chemokines and chemokine receptor system at the maternal–fetal interface. Numerous studies have reported that they not only regulate trophoblast biological behaviors but also participate in the decidual immune response. At the same time, the chemokine system builds an important communication network between fetally derived trophoblast cells and maternally derived decidual cells. However, abnormal functions of chemokines or chemokine receptors are involved in a series of pregnancy complications. As growing evidence points to the roles of chemokines in pregnancy, there is a great need to summarize the available data on this topic. This review aimed to describe the recent research progress on the regulation and function of the main chemokines in pregnancy at the maternal–fetal interface. In addition, we also discussed the potential relationship between chemokines and pregnancy complications.

Small RNA sequencing reveals placenta-derived exosomal microRNAs associated with preeclampsia

OBJECTIVE

Preeclampsia is one of the most important complications during pregnancy and the leading cause of maternal morbidity and mortality; however, the pathogenesis of preeclampsia remains partially misunderstood. The aim of this study was to identify placenta-derived exosomal microRNAs (miRNAs) involved in the preeclampsia process.

METHODS

Peripheral blood was collected from normal and preeclampsia pregnant women, and placenta-derived exosomes were extracted. Small RNA sequencing was performed to identify the exosomal miRNAs involved in preeclampsia. The function of a differentially expressed exosomal miRNA was verified.

RESULTS

The extracted exosomes presented round or oval-like structures with diameters of approximately 80 nm and could be recognized by antibodies against CD9, CD81, and placental alkaline phosphatase. A total of 1013 exosomal miRNAs were identified by small RNA sequencing, of which 946 were known miRNAs and 67 were novel miRNAs. Twenty-six miRNAs were identified as differentially expressed when comparing the data of the preeclampsia and normal groups. One of the differentially expressed miRNAs, hsa-miR-370-3p, which was upregulated in the preeclampsia group, was shown to bind to the 3' untranslated region of C-X-C motif chemokine 12, a chemokine that plays important role during preeclampsia process. Moreover, functional analysis revealed that hsa-miR-370-3p could inhibit proliferation, migration, and invasion while promoting apoptosis of HTR-8/SVneo cells.

CONCLUSION

A total of 1013 placenta-derived exosomal miRNAs were identified by small RNA sequencing, of which 26 were differentially expressed. The function of one differentially expressed miRNA (hsa-miR-370-3p) was verified. Our results provide new perspectives on the pathogenesis of preeclampsia and potential biomarkers for preeclampsia diagnosis.