Association of maternal Toll-like receptor-4 alleles with susceptibility to early-onset preeclampsia in central Greece

The relationship between Toll-like receptor-4 genes and preeclampsia outcomes

PURPOSE

The study aimed to analyse the relationship of the rs4986790 locus of the TLR4 gene with the overall risk of preeclampsia, including both its early and late forms.

METHODS

The study used standard genetic analysis methods such as DNA extraction, PCR amplification, and genotyping of the rs4986790 locus of the TLR4 gene to assess the association with the development of preeclampsia and peripartal stroke in 207 pregnant women from the southern regions of Kazakhstan from 2016 to 2022, of whom 103 had peripartal stroke on the background of preeclampsia (the main group) and 104 preeclampsia (comparative group).

RESULTS

The results of the study demonstrate that the AG and AG + GG genotypes at the rs4986790 locus of the TLR4 gene are significantly associated with an increased risk of developing an early form of preeclampsia. This opens up a new perspective in the identification of genetic markers that can serve as indicators of a tendency to develop preeclampsia in earlier periods of pregnancy.

CONCLUSION

It was noted that the rs4986790 locus did not show a statistically significant association with the risk of late preeclampsia. An important aspect of the study revealed the relationship of genotypes with the development of peripartal stroke on the background of preeclampsia. This study offers practical insights for creating targeted genetic screening and personalised treatments for preeclampsia, aiming to improve patient outcomes. To fully understand the molecular mechanisms underlying the identified association, additional research is required to identify deeper molecular pathways and relationships, and to develop new strategies for the prevention and treatment of preeclampsia.

Maternal serum pregnancy-associated plasma protein-A concentration at 11-14 weeks of gestation and preeclampsia risk of women with common congenital anatomic uterine abnormalities

To evaluate maternal serum pregnancy-associated plasma protein-A (PAPP-A) levels at 11-14 weeks of gestation and preeclampsia risk in women with common congenital anatomic uterine abnormalities (AUAs). First trimester screening markers were compared between 12 AUA pregnancies, 60 age matched controls and 12 cases of early preeclampsia. PAPP-A level and birth weight were significantly lower in AUA compared to control and early preeclampsia group (p<.001). Preeclampsia was absent in the AUAs pregnancies group. Birth weight were similar in AUA group when we compared AUA and control group regarding weeks of gestation at delivery and lower but not significantly, when we compared AUA and early preeclampsia group. Our findings suggest that AUA pregnancies are associated with low first trimester maternal serum PAPP-A concentrations not predictive of susceptibility to preeclampsia.Impact statementWhat is already known on this subject? During first trimester screening for preeclampsia based on maternal pregnancy-associated plasma protein A (PAPP-A) levels, various parameters are used, such as the somatometric characteristics of pregnant woman, single or multiple pregnancy, smoking status, family history, diabetes, hypertension and measurement of blood pressure and uterine artery Dopplers.What do the results of this study add? Our pioneer study revealed that there is drastic difference in PAPP-A concentration in women with common anatomic uterine abnormalities (AUAs), in comparison with their age matched control women with normal uterus.What are the implications of these findings for clinical practice and further research? Based on our results, uterine anatomical deviations, is another factor which must be taken in account for preeclampsia risk calculation and further clinical consultation and follow up in those pregnancies. Lower PAPP-A levels in AUA cases is a weak predictor of susceptibility to preeclampsia and could be associated to smaller placental size rather than poor placentation and in future research the calculation of the uterine cavity functional dimension may lead to a more accurate clinical assessment.

Association Between TLR4 Gene Polymorphisms and Risk of Preeclampsia: Systematic Review and Meta-Analysis

BACKGROUND Toll-like receptor 4 (TLR4) plays a pivotal role in the innate immune response and is hyperactivated in preeclampsia (PE). Several researchers have published conflicting evidence for TLR4 rs4986790 and rs4986791 single nucleotide polymorphisms (SNPs) as risk factors for PE. The present meta-analysis was conducted to obtain a more definitive conclusion about the effects of these SNPs on PE susceptibility. MATERIAL AND METHODS To determine the correlation between rs4986790 and rs4986791 polymorphisms in the TLR4 gene and susceptibility to PE, the PubMed, Web of Science, EMBASE, Chinese National Knowledge Infrastructure, and Chinese WANFANG databases were searched for eligible articles. Statistical analysis was performed with STATA software, version 12.0. Pooled odds ratios with corresponding 95% confidence intervals (CIs) were extracted for assessment of correlation strength. RESULTS We identified 5 studies including 578 cases and 631 controls for the rs4986790 SNP and 4 studies including 469 cases and 457 controls for the rs4986791 SNP, mainly from a White population. The pooled analyses showed no statistical relationship between the polymorphisms rs4986790 and rs4986791 and PE susceptibility in 5 genetic models (all P>0.05). Moreover, the allelic and dominant gene models of rs4986790 and the allelic, heterozygous, and dominant gene models of rs4986791 had high heterogeneity. The sensitivity analysis explored potential sources of heterogeneity and confirmed the findings of this meta-analysis. CONCLUSIONS TLR4 rs4986790 and rs4986791 polymorphisms may not be implicated in PE susceptibility, primarily in a White population. More high-quality studies of genetic associations with PE are warranted.

Association of maternal angiotensin II type 1 and type 2 receptor combination genotypes with susceptibility to early-onset preeclampsia

Allelic variations affecting the activity of the maternal renin-angiotensin system may play a role in the development of hypertensive disorders of pregnancy like preeclampsia, its more severe early-onset form, and intrauterine growth restriction. We examined the association of common allelic variants of angiotensin II type 1 and type 2 receptor genes (AT1R and AT2R) sorted in five AT1R/AT2R receptor combination genotype groups with susceptibility to early-onset preeclampsia (EOP). The occurrence of AT1R (A1166C) and A2TR (C3123A) alleles in wild type (AA, CC), heterozygous (A/C, C/A), and homozygous (C/C, A/A) states was recorded in 84 women with a history of EOP and 84 age-matched controls sorted in five AT1R/AT2R receptor combination genotype (wild type: AA/CC, one mutant: AA/CA, AC/CC, two mutant: AC/CA, AA/AA, CC/CC, three mutants: AC/AA, CC/CA and four mutant: CC/AA) groups, by polymerase chain reaction-RFLP analysis. Three mutant receptor combination genotype carriers were more common in women with a history of EOP than in controls (26.18% vs. 4.76%, p = 0.003, OR = 8.25). Receptor combination genotyping may be of clinical value in: (a) maternal prediction of susceptibility to EOP, (b) disease subtyping for directed studies with receptor signaling antagonists, (c) the broader study of hypertension.