The role of inflammatory biomarkers in the development and progression of pre-eclampsia: a systematic review and meta-analysis

Raised levels of chemerin in women with preeclampsia: A meta-analysis

Chemerin is a multifunctional adipokine associated with systemic inflammation, angiogenesis, and oxidative stress. Emerging evidence suggests a potential link between chemerin and the pathogenesis of preeclampsia (PE). In this systematic review and meta-analysis, we aimed to evaluate the serum chemerin levels in women with PE. A systematic search was conducted across Medline, Web of Science, and Embase databases from inception until April 15, 2023, to identify studies comparing serum chemerin levels in pregnant women with and without PE. A random-effects model was employed to pool the results, accounting for heterogeneity. Thirteen datasets from 10 observational studies, encompassing 832 women with PE and 1298 healthy pregnant women, were analyzed. The pooled findings indicated a statistically significant elevation in serum chemerin levels in women with PE compared to controls (mean difference [MD] = 89.56 ng/mL, 95% confidence interval [CI] 62.14 - 116.98; P < 0.001; I2 = 87%). The subgroup analysis revealed consistent findings across studies that measured chemerin levels before or after the diagnosis of PE, studies that did or did not match the body mass index (BMI), and studies with varying quality scores (P values for subgroup differences were all > 0.05). Compared to controls, women with severe PE exhibited a significantly greater increase in serum chemerin levels than those with mild PE (P value for subgroup difference = 0.007). Additionally, meta-regression analysis results suggested that the mean BMI of the included pregnant women might positively modify the difference in circulating chemerin levels between women with and without PE (coefficient = 8.92; P = 0.045). In conclusion, this meta-analysis suggests a positive correlation between elevated serum chemerin levels and PE diagnosis in comparison to pregnant women without the condition.

Systemic inflammatory regulators and preeclampsia: a two-sample bidirectional Mendelian randomization study

Background

Systemic inflammatory regulators have been associated with preeclampsia (PE) during pregnancy; however, there is inconsistent evidence from animal models and observational results.

Methods

Using summary data from genome-wide association studies (GWASs), we performed a bidirectional Mendelian randomization (MR) analysis of two samples of systemic inflammatory regulators (n = 8,186) and PE (n = 267,242) individuals of European ancestry. As our primary analysis, we used the random-effects inverse-variance weighted (IVW) approach. Sensitivity and pleiotropy analyses were conducted using the MR-Egger method, weighted median, MR Pleiotropy RESidual Sum and Outlier (MR-PRESSO), and Cochran's Q test.

Results

The results indicate that there is a correlation between a higher circulating level of tumor necrosis factor alpha (TNF-α) and interleukin-9 (IL-9) and an increased risk of PE (odds ratio [OR] = 1.32, 95% confidence interval [CI] = 1.09-1.60, p = 0.004 and OR = 1.28, 95% CI: 1.02-1.62, p = 0.033, respectively). Conversely, lower levels of stem cell growth factor beta (SCGF-β) (OR = 0.89, 95% CI: 0.80-0.99, p = 0.027) and interleukin-5 (IL-5) (OR = 0.80, 95% CI: 0.65-0.98, p = 0.030) are linked to an increased risk of PE. The macrophage migration inhibitory factor (MIF) is the downstream inflammatory regulator of PE, according to reverse magnetic resonance imaging studies.

Conclusion

Our study suggests that SCGF-β, IL-5, IL-9, and TNF-α causally affect the PE risk, while PE is causally associated with MIF. Further studies are needed to validate these biomarkers in managing PE.

Phthalate exposure increases interferon-γ during pregnancy: The Atlanta African American Maternal-Child Cohort

BACKGROUND

The immune system undergoes unique adaptations during pregnancy and is particularly sensitive to environmental chemicals, such as phthalates, which are associated with acute and chronic inflammatory medical conditions. However, current knowledge of how phthalate exposures are associated with systemic inflammation in pregnant people is limited by cross-sectional study designs and single chemical models. Our objective was to estimate the association between repeated measures of prenatal phthalate exposures, examined individually and collectively, and a panel of clinical inflammatory biomarkers.

METHODS

In the Atlanta African American Maternal-Child Cohort, biospecimens were collected at mean 11 and 26 weeks gestation (N = 126). Concentrations of eight urinary phthalate metabolites and five serum inflammatory biomarkers, including CRP, IFN-γ, IL-6, IL-10, and TNF-α, were measured. Linear mixed effect regression and quantile g-computation models were used to estimate the associations for single phthalates and their exposure mixture, respectively.

RESULTS

Participants who self-reported any use of alcohol, tobacco, or marijuana in the month prior to pregnancy had increased MEP, MBP, MiBP, and CRP, relative to those with no substance use. IFN-γ was elevated in response to MECPP (% change = 17.35, 95 % confidence interval [CI] = 0.32, 32.27), MEHHP (% change = 12.75, 95 % CI = 2.22, 24.36), MEOHP (% change = 11.63, 95 % CI = 1.21, 23.12), and their parent phthalate, ΣDEHP (% change = 15.03, 95 % CI = 0.28, 31.94). The phthalate mixture was also associated with an increase in IFN-γ (% change = 15.03, 95 % CI = 6.18, 24.61).

CONCLUSIONS

Our findings suggest DEHP metabolites induce systemic inflammation during pregnancy. The pro-inflammatory cytokine IFN-γ may play an important role in the relationship between prenatal phthalate exposures and adverse pregnancy outcomes.

Identification of gene signature markers in gestational hypertension and early-onset pre-eclampsia

INTRODUCTION

Hypertensive disorders in pregnancy (HDP) are the leading cause of perinatal mortality worldwide. Inflammatory responses induced by insufficient placental perfusion have become a focal point in understanding the pathogenesis and aetiology of HDP and developing reliable and consistent biomarkers. Therefore, this study aims to identify gene signatures linked to the pathophysiology of HDP (gestational hypertension and early and late-onset pre-eclampsia).

METHODS

RNA was extracted from the maternal serum from the blood samples collected from different groups of HDP patients. A multiplex inflammation panel (255 inflammatory and housekeeping genes) and further gene expression analysis using NanoString Digital Direct Detection were done. The prominent expressions of these genes were further validated through qPCR techniques.

RESULTS

NanoString analysis identified nine unique, significantly expressed genes (MAPK1, MAPK3, MAFF, HLA-DRA, IL12B, RHOA, MASP2, MEF2A and NR3C1) between specific group comparisons of different HPD classes and the normotensive groups. The qPCR showed that the HLA-DRA gene was significantly upregulated in the early-onset pre-eclamptic and gestational hypertensive group compared to its respective normotensive group. In contrast, MAFF and MEF2A were significantly downregulated in both HDPs compared to their controls. The MAPK1 gene was significantly higher in the early-onset group compared to the gestational hypertensive and normotensive groups.

DISCUSSION

The upregulation of these distinctive genes in hypertensive groups compared to normotensives confirmed their diagnostic potential. Therefore, HLA-DRA, MAFF and MEF2A could be candidate markers of HDP, while the MAPK1 gene could be a differentiating marker between early-onset pre-eclampsia and gestational hypertension.

Role of neutrophil / lymphocyte ratio, uric acid / albumin ratio and uric acid / creatinine ratio as predictors to severity of preeclampsia

BACKGROUND

Pre-eclampsia (PE) is an intractable obstetric disorder with high mortality and morbidity, affecting 6-8% of pregnancies worldwide. As its etiology and pathogenesis remain unclear, there are no specific prevention or treatment options. This study aimed to determine the association between neutrophil to lymphocyte ratio (NLR), uric acid to albumin ratio (UAR) and uric acid to creatinine ratio (UA/Cr) and severity of pre-eclampsia.

METHODS

A cross-sectional hospital-based study was conducted among pre-eclamptic women in Kosti Maternity Hospital from September to December 2022. Forty-five pre-eclamptic women were enrolled in this study and were classified according to the WHO classification of PE into mild PE (23 PE patients) and severe PE (22 PE patients). Data were collected using a semi-structured questionnaire covering medical history and clinical assessment. A blood sample was taken from each participant for measurements of the complete blood count (CBC), liver functions test (LFT) with enzymes, renal functions test (RFT) with electrolytes, and uric acid by standard techniques.

RESULTS

NLR was found to be statistically significantly higher in mothers with severe PE (6.3-9.9) than in those with mild PE (2.2-1.5) (p-value 0.048). Alanine aminotransferase (ALT) was significantly higher in women with severe PE than in those with mild PE (p-value = 0.02). The total means of platelet-lymphocyte ratio (PLR), UA/Cr, and UAR were insignificantly higher in women with severe PE compared with those with mild PE (p-values 0.666, 0.427, and 0.525, respectively). The means of uric acid and serum creatinine showed insignificant statistical elevation in women with severe PE compared with mild PE (p-values of 0.27 and 0.44, respectively). Serum albumin was found to be insignificantly lower in mothers with severe PE (3.3 ± 0.6 g/dl) than in those with mild PE (3.6 ± 0.6 g/dl); p-value = 0.21.

CONCLUSIONS

PE showed a significant statistical increase in WBC, neutrophils, alanine transaminase (ALT), and NLR in severe PE compared to mild PE and a significant statistical decrease in lymphocyte count in severe PE compared to mild PE. The measurement of NLR may be a useful laboratory marker for predicting the severity of PE.

Potential Inflammatory Biomarkers for Major Depressive Disorder Related to Suicidal Behaviors: A Systematic Review

Major depressive disorder (MDD) is a highly prevalent psychiatric condition affecting an estimated 280 million individuals globally. Despite the occurrence of suicidal behaviors across various psychiatric conditions, MDD is distinctly associated with the highest risk of suicide attempts and death within this population. In this study, we focused on MDD to identify potential inflammatory biomarkers associated with suicidal risk, given the relationship between depressive states and suicidal ideation. Articles published before June 2023 were searched in PubMed, Embase, Web of Science, and the Cochrane Library to identify all relevant studies reporting blood inflammatory biomarkers in patients with MDD with suicide-related behaviors. Of 571 articles, 24 were included in this study. Overall, 43 significant biomarkers associated with MDD and suicide-related behaviors were identified. Our study provided compelling evidence of significant alterations in peripheral inflammatory factors in MDD patients with suicide-related behaviors, demonstrating the potential roles of interleukin (IL)-1β, IL-6, C-reactive protein, C-C motif chemokine ligand 2, and tumor necrosis factor-α as biomarkers. These findings underscore the intricate relationship between the inflammatory processes of these biomarkers and their interactions in MDD with suicidal risk.