Hypertensive disorders of pregnancy: Strategy to develop clinical peptide biomarkers for more accurate evaluation of the pathophysiological status of this syndrome

The Hidden Relationship between Intestinal Microbiota and Immunological Modifications in Preeclampsia Pathogenesis

Preeclampsia is a multifactorial gestational syndrome characterized by increased blood pressure during pregnancy associated with multiorgan involvement. The impact of this disease on maternal and neonatal health is significant, as it can lead to various fetal comorbidities and contribute to the development of maternal comorbidities later in life. Consistent evidence has shown that the microbiota acts as a regulator of the immune system, and it may, therefore, influence the development of preeclampsia by modulating immune factors. This narrative review aims to investigate the role of the immune system in the pathogenesis of preeclampsia and to summarize the most recent literature on the possible link between preeclampsia and alterations in the intestinal microbiota. To this end, we conducted a literature search, aiming to perform a narrative review, on PubMed and Embase from January 1990 to March 2024, focusing on the latest studies that highlight the main differences in microbial composition between patients with and without preeclampsia, as well as the effects of microbial metabolites on the immune system. From the review of 28 studies assessing the intestinal microbiota in preeclamptic women, preeclampsia could be associated with a state of dysbiosis. Moreover, these patients showed higher plasmatic levels of endotoxin, pro-inflammatory cytokines, and T helper 17 cells; however, the findings on specific microbes and metabolites that could cause immune imbalances in preeclampsia are still preliminary.

Preeclampsia up to date-What's going on?

Preeclampsia is a hypertensive disorder in pregnancy characterized by placental malperfusion and subsequent multi-organ injury. It accounts for approximately 14% of maternal deaths and 10-25% of perinatal deaths globally. In addition, preeclampsia has been attracting attentions for its association with risks for developing chronic diseases in later life for both mother and child. This mini-review discusses on latest knowledge on prediction, prevention, management, and long-term outcomes of preeclampsia and also touches on association between COVID-19 and preeclampsia. HTN hypertension, HDP hypertensive disorders of pregnancy, PE preeclampsia, BP blood pressure, cfDNA cell-free DNA, ST2 human suppression of tumorigenesis 2, sFlt-1 soluble fms-like tyrosine kinase-1, PIGF placental growth factor, VEGF vascular endothelial growth factor, VEGFR VEGF receptor, TGFβ transforming growth factor β, ENG endoglin, sENG soluble ENG, PRES posterior reversible encephalopathy syndrome, AKI acute kidney injury, CVD cardiovascular disease, ESKD end-stage kidney disease, ACE angiotensinogen converting enzyme, Ang angiotensin.

High miR-200a-3p expression has high diagnostic values for hypertensive disorders complicating pregnancy and predicts adverse pregnancy outcomes

BACKGROUND

Hypertensive disorders complicating pregnancy (HDCP) are various heterogeneous conditions. microRNA (miR)-200a-3p is involved in HDCP diagnosis. This study explored the effects of miR-200a-3p on HDCP patients.

METHODS

A total of 126 singleton HDCP patients including 50 cases of gestation hypertension (GH), 42 cases of mild preeclampsia (MP) and 34 cases of severe preeclampsia (SP), were enrolled as study subjects, and 50 normal pregnant women were selected as the control. Serum miR-200a-3p expression was detected and its efficacy in HDCP diagnosis and grading was evaluated. GH, MP and SP patients were allocated to high/low miR-200a-3p expression groups. The correlation between miR-200a-3p expression and general clinical indexes was analyzed. HDCP patients were allocated to high/low miR-200a-3p expression group and maternal and fetal outcomes were followed up. Effects of miR-200a-3p expression on adverse pregnancy outcome incidence were analyzed.

RESULTS

miR-200a-3p expression in the serum of HDCP patients was upregulated. The sensitivity and specificity of serum miR-200a-3p level > 1.201 were 87.3% and 96.0%, respectively. Serum miR-200a-3p level in GH, MP and SP patients was increased with the aggravation of the disease. The cut-off value and area under the curve (AUC) of miR-200a-3p for GH, MP and SP diagnosis were 1.145 and 0.9094 (82.0% sensitivity and 88.0% specificity), 1.541 and 0.8126 (73.8% sensitivity and 76.0% specificity), and 1.866 and 0.7367 (64.7% sensitivity and 76.2% specificity), respectively. Serum miR-200a-3p level was correlated with general clinical indexes, fetal birth weight, systolic to diastolic ratio, and fetal growth restriction incidence. High serum miR-200a-3p expression in HDCP patients was associated with increased adverse pregnancy outcomes.

CONCLUSION

High miR-200a-3p expression could help to diagnose HDCP, judge severity and was associated with increased adverse pregnancy outcomes.

Associations of cardiovascular risk with circulating peptides related to hypertensive disorders of pregnancy

We previously identified seven peptides in serum that are associated with hypertensive disorders of pregnancy (HDP). However, the significance of these peptides in the general population is unknown. The aim of this study was to clarify the relationships of HDP-associated peptides with hypertension and other cardiovascular risks in adult men. We investigated the relationships of peptide levels with cardiovascular risk factors, including adiposity, blood pressure, blood lipids and glycemic status, in men (mean age: 46.4 years) who were receiving annual health checkups at their workplace. The concentrations of the abovementioned seven peptides in serum were measured simultaneously using a mass spectrometer. Among the seven peptides, only a peptide with m/z 2091 (P-2091) derived from fibrinogen-α showed a significant correlation with diastolic blood pressure (Spearman's rank correlation coefficient [r], -0.446). Another peptide with m/z 2378 (P-2378) originating from complement component 4 showed a significant positive correlation with body mass index (r, 0.273) and a significant inverse correlation with HDL cholesterol (r, -0.336). In addition, a peptide with m/z 3156 (P-3156) derived from an inter-α-trypsin inhibitor showed significant inverse correlations with body mass index (r, -0.258) and triglycerides (r, -0.334). There was no significant correlation of the levels of any of the seven peptides with hemoglobin A1c. Among the seven peptides related to HDP, P-2091, P-2378 and P-3156 were inversely associated with diastolic blood pressure, HDL cholesterol and triglycerides, respectively. Therefore, these peptides are possible biomarkers for discriminating cardiovascular risk in a general population.

Exploration of novel biomarkers for hypertensive disorders of pregnancy by comprehensive analysis of peptide fragments in blood: their potential and technologies supporting quantification

Among the many complications associated with pregnancy, hypertensive disorders of pregnancy (HDP) constitute one of the most important. Since the pathophysiology of HDP is complex, new disease biomarkers (DBMs) are needed to serve as indicators of disease activity. However, in the current status of laboratory medicine, despite the fact that blood pressure measurement has been used for a long time, not many DBMs contribute adequately to the subsequent diagnosis and treatment. In this article, we discuss studies focusing on peptide fragments in blood identified by comprehensive quantitative methods, among the currently proposed DBM candidates. Furthermore, we describe the basic techniques of peptidomics, especially quantitative proteomics, and outline the current status and challenges of measuring peptides in blood as DBM for HDP.

An overview of sex and reproductive immunity from an evolutionary/anthropological perspective

Mammalian pregnancy is a curious life phenomenon. Immunologically, the mechanism of pregnancy is difficult to explain because it involves the coexistence of an external foreign body (the embryo) and the host (the mother) for a period of time. How did mammals acquire the ability to become pregnant in parallel with altered immunity? Sex in the evolution of life and its impact on anthropology are major topics of discussion. In this paper, we outline (1) sex and evolution in mammals after the advent of our direct ancestors (apes) up to humans (i.e., the Cenozoic Quaternary), including anthropological aspects such as the development of the central nervous system; (2) the development of reproductive immunity during the Paleozoic era, when biodiversity developed explosively (and many sexually reproducing organisms have emerged); and (3) the characteristic reproductive strategies of mammals, including humans with the immunological aspects of viviparity. We present an overview of mammalian reproductive immunity, which is a heretical aspect of immunology.