Functional and molecular characterization of endothelium-dependent and endothelium-independent relaxant pathways in uterine artery of non-pregnant buffaloes

Identification of biomarkers and sex differences in the placenta of fetal growth restriction

AIM

Fetal growth restriction (FGR) can lead to short-term and long-term impairments in the fetus. The placenta functions as an exchanger for substance transport, playing a critical role in fetal growth. However, the mechanism from the placental standpoint is still not fully understood. In this study, we aimed to investigate the pathophysiological mechanisms in the placenta that mediated the development of FGR and sex differences.

METHODS

We analyzed the gene expression profiles of GSE100415 containing specific normotensive FGR placental samples and GSE114691 with canonical samples using three different methods, differentially expressed gene analysis, weighted gene co-expression network analysis, and gene set enrichment analysis. Gene enrichment was performed, including the gene ontology and pathway from the Kyoto Encyclopedia of Genes and Genomes. The important process was then validated in pregnant Wistar rats subcutaneously administered dexamethasone (0.2 mg/kg/d) or saline from gestation Day 9 to 21.

RESULTS

Our results revealed little difference between the comparison of normal and normotensive FGR placental samples but confirmed the sex difference. Further analyses of the canonical samples identified the occurrence of vascular dysfunction, which was validated by the calculation of the vascular lumen area, showing that the vascular lumen in the FGR group was more than in the control. We also discovered 17 significantly expressed genes from the involved eigengenes.

CONCLUSION

Our study provides an important theoretical and experimental basis to reevaluate the development of FGR from the placental standpoint and suggests a series of biomarkers for future clinical use.

Potassium Channels in the Uterine Vasculature: Role in Healthy and Complicated Pregnancies

A progressive increase in maternal uterine and placental blood flow must occur during pregnancy to sustain the development of the fetus. Changes in maternal vasculature enable an increased uterine blood flow, placental nutrient and oxygen exchange, and subsequent fetal development. K⁺ channels are important modulators of vascular function, promoting vasodilation, inducing cell proliferation, and regulating cell signaling. Different types of K⁺ channels, such as Ca²⁺-activated, ATP-sensitive, and voltage-gated, have been implicated in the adaptation of maternal vasculature during pregnancy. Conversely, K⁺ channel dysfunction has been associated with vascular-related complications of pregnancy, including intrauterine growth restriction and pre-eclampsia. In this article, we provide an updated and comprehensive literature review that highlights the relevance of K⁺ channels as regulators of uterine vascular reactivity and their potential as therapeutic targets.