Maternal and fetal Leptin and interleukin 33 concentrations in pregnancy complicated by obesity and preeclampsia

Periconceptional biomarkers for maternal obesity: a systematic review

Periconceptional maternal obesity is linked to adverse maternal and neonatal outcomes. Identifying periconceptional biomarkers of pathways affected by maternal obesity can unravel pathophysiologic mechanisms and identify individuals at risk of adverse clinical outcomes. The literature was systematically reviewed to identify periconceptional biomarkers of the endocrine, inflammatory and one-carbon metabolic pathways influenced by maternal obesity. A search was conducted in Embase, Ovid Medline All, Web of Science Core Collection and Cochrane Central Register of Controlled Trials databases, complemented by manual search in PubMed until December 31^st, 2020. Eligible studies were those that measured biomarker(s) in relation to maternal obesity, overweight/obesity or body mass index (BMI) during the periconceptional period (14 weeks preconception until 14 weeks post conception). The ErasmusAGE score was used to assess the quality of included studies. Fifty-one articles were included that evaluated over 40 biomarkers. Endocrine biomarkers associated with maternal obesity included leptin, insulin, thyroid stimulating hormone, adiponectin, progesterone, free T4 and human chorionic gonadotropin. C-reactive protein was associated with obesity as part of the inflammatory pathway, while the associated one-carbon metabolism biomarkers were folate and vitamin B12. BMI was positively associated with leptin, C-reactive protein and insulin resistance, and negatively associated with Free T4, progesterone and human chorionic gonadotropin. Concerning the remaining studied biomarkers, strong conclusions could not be established due to limited or contradictory data. Future research should focus on determining the predictive value of the optimal set of biomarkers for their use in clinical settings. The most promising biomarkers include leptin, adiponectin, human chorionic gonadotropin, insulin, progesterone and CRP.

Association of LEPTIN and other inflammatory markers with preeclampsia: A systematic review

Background: Preeclampsia is a serious pregnancy complication that affects 5%–10% of the obstetric population.

Objective: To study inflammatory markers associated with preeclampsia.

Search Strategy: Searches of articles on the topic published over a 10-year period (2009–2019) were performed in three databases (PubMed, Cochrane, and Embase) using the keywords preeclampsia and inflammatory markers. The PubMed search using 10 years and humans as filters retrieved 124 articles. Using an advanced search strategy, 0 articles were identified in Embase and 10 articles in Cochrane. After screening and eligibility assessment, 13 articles were included in the systematic review and meta-analysis. Meta-analysis and quality assessment of the studies were performed using the Review Manager 5.3 program.

Results: For meta-analysis, women with preeclampsia were compared to control women, i.e., pregnancies without arterial hypertension. Leptin levels were significantly higher (p < 0.0002) in women with preeclampsia compared to controls. Total cholesterol was also significantly elevated in women with preeclampsia (p < 0.0001). There was no significant difference in HDL between groups, but women with preeclampsia had significantly increased LDL (p < 0.01). The same was observed for triglycerides, which were significantly increased in women with preeclampsia (p < 0.04) compared to controls. Analysis of TNF-alpha, an important inflammatory marker, showed higher levels in women with preeclampsia (p < 0.03) compared to controls. The same was observed for another important inflammatory marker, interleukin 6, which was significantly increased in women with preeclampsia (p < 0.0002). There was a significant increase of C-reactive protein in women with preeclampsia (p < 0.003) compared to controls.

Conclusion: Women with preeclampsia have increased levels of inflammatory markers compared to control women.

Increased levels of serum IL-33 is associated with adverse maternal outcomes in placenta previa accreta

PURPOSE

IL-33 is associated with invasion, proliferation, and metastasis of various cancers. The trophoblastic cells of placenta previa accreta (PPA) invade into the myometrium in a similar way to the invasion of cancers. We studied the role of IL-33 in PPA and also aimed to investigate its relation with adverse maternal outcome in this placental disorder.

METHODS

A total of 87 pregnant patients were enrolled in this prospective case-control study [27 with PPA, 30 with placenta previa totalis (PPT; nonadherent placenta previa), and 30 controls]. IL-33 and IL-6 levels were studied in maternal serum at late preterm gestation weeks. Multiple logistic regression analyses analyzed the risk factors which are associated with PPA and adverse maternal outcomes. Adjusted odds ratios and 95% confidence intervals were also calculated. Enzyme-linked immunosorbent assay (ELISA) method was used to determine maternal serum IL-33 and IL-6 levels.

RESULTS

Serum IL-33 levels were significantly higher in PPA patients when compared with both nonadherent PPT and the control groups (p = .011, p = .010). Serum IL-6 and neutrophil/lymphocyte ratio levels were significantly higher than the control group's (p = .045, p = .028). IL-33 levels and history of previous cesarean section were found to be significantly associated with PPA (OR: 1.039, 95% CI: 1.004-1.075; p = .030 and OR: 0.067, 95% CI: 0.014-0.309, p = .001, respectively). Serum IL-33 levels were positively correlated with previous cesarean section history in PPA. Increased maternal serum IL-33 levels were found to be independently associated with a cesarean hysterectomy and massive transfusion in PPA patients (OR: 1.098, 95% CI: 0.998-1.207; p = .049 and OR: 1.162 95% CI: 1.010-1.337; p = .036).

CONCLUSION

Increased levels of maternal serum IL-33 and history of previous cesarean section were found to be significantly associated with PPA, and also increased maternal serum IL-33 levels were related to cesarean hysterectomy and massive blood transfusion in PPA. We suggest that IL-33 may have a role in abnormal placental invasion.