Renal dysfunction and podocyturia in pre-eclampsia may be explained by increased urinary VEGF

Preeclampsia: A comprehensive review

Preeclampsia (PE) is a life-threatening disease of pregnancy and a prominent cause of neonatal and maternal mortality and morbidity. PE affects approximately 5-10% of pregnancies worldwide, posing significant risks to perinatal and maternal health. It is characterized by a variety of interconnected pathological cascades contributing to the stimulation of intravascular inflammation, oxidative stress (OS), endothelial cell activation, and syncytiotrophoblast stress that converge on a common pathway, ultimately resulting in disease progression. The present study was designed and executed to review the existing scientific literature, specifically focusing on the etiology (gestational diabetes mellitus and maternal obesity, insulin resistance, metabolic syndrome, maternal infection, periodontal disease, altered microbiome, and genetics), clinical presentations (hypertension, blood disorders, proteinuria, hepatic dysfunction, renal dysfunction, pulmonary edema, cardiac dysfunction, fetal growth restrictions, and eclampsia), therapeutic clinical biomarkers (creatinine, albuminuria, and cystatin C) along with their associations and mechanisms in PE. In addition, this study provides insights into the potential of nanomedicines for targeting these mechanisms for PE management and treatment. Inflammation, OS, proteinuria, and an altered microbiome are prominent biomarkers associated with progression and PE-related pathogenesis. Understanding the molecular mechanisms, exploring suitable markers, targeted interventions, comprehensive screening, and holistic strategies are critical to decreasing the incidence of PE and promoting maternal-fetal well-being. The present study comprehensively reviewed the etiology, clinical presentations, therapeutic biomarkers, and preventive potential of nanomedicines in the treatment and management of PE.

Preeclampsia at term: evidence of disease heterogeneity based on the profile of circulating cytokines and angiogenic factors

BACKGROUND

Intravascular inflammation and an antiangiogenic state have been implicated in the pathophysiology of preeclampsia. On the basis of the profiles of their angiogenic/antiangiogenic factors, women with preeclampsia at term may be classified into 2 subgroups with different characteristics and prevalence of adverse outcomes. This study was undertaken to examine whether these 2 subgroups of preeclampsia at term also show differences in their profiles of intravascular inflammation.

OBJECTIVE

This study aimed to determine the plasma profiles of cytokines and chemokines in women with preeclampsia at term who had a normal or an abnormal angiogenic profile.

STUDY DESIGN

A nested case-control study was conducted to include women classified into 3 groups: women with an uncomplicated pregnancy (n=213) and women with preeclampsia at term with a normal (n=55) or an abnormal (n=41) angiogenic profile. An abnormal angiogenic profile was defined as a plasma ratio of placental growth factor and soluble fms-like tyrosine kinase-1 multiple of the median <10th percentile for gestational age. Concentrations of cytokines were measured by multiplex immunoassays.

RESULTS

Women with preeclampsia at term and an abnormal angiogenic profile showed evidence of the greatest intravascular inflammation among the study groups. These women had higher plasma concentrations of 5 cytokines (interleukin-6, interleukin-8, interleukin-12/interleukin-23p40, interleukin-15, and interleukin-16) and 7 chemokines (eotaxin, eotaxin-3, interferon-γ inducible protein-10, monocyte chemotactic protein-4, macrophage inflammatory protein-1β, macrophage-derived chemokine, and thymus and activation-regulated chemokine compared to women with an uncomplicated pregnancy. By contrast, women with preeclampsia at term and a normal angiogenic profile, compared to women with an uncomplicated pregnancy, had only a higher plasma concentration of monocyte chemotactic protein-4. A correlation between severity of the antiangiogenic state, blood pressure, and plasma concentrations of a subset of cytokines was observed.

CONCLUSION

Term preeclampsia can be classified into 2 clusters. One is characterized by an antiangiogenic state coupled with an excessive inflammatory process, whereas the other has neither of these features. These findings further support the heterogeneity of preeclampsia at term and may explain the distinct clinical outcomes.

Potential urinary biomarkers in preeclampsia: a narrative review

INTRODUCTION

Preeclampsia (PE) is a highly relevant pregnancy-related disorder. An early and accurate diagnosis is crucial to prevent major maternal and neonatal complications and mortality. Due to the association of kidney dysfunction with the pathophysiology of the disease, urine samples have the potential to provide biomarkers for PE prediction, being minimally invasive and easy to perform. Therefore, searching for novel biomarkers may improve outcomes. This narrative review aimed to summarize the scientific literature about the traditional and potential urinary biomarkers in PE and to investigate their applicability to screen and diagnose the disorder.

METHODS

A non-systematic search was performed in PubMed/MEDLINE, Scopus, and SciELO databases.

RESULTS

There is significant divergence in the literature regarding traditionally used serum markers creatinine, cystatin C, and albuminuria, accuracy in PE prediction. As for the potential renal biomarkers investigated, including vascular epithelial growth factor (VEGF), placental growth factor (PlGF), and soluble fms-like tyrosine kinase (sFlt-1), urinary levels of PlGF and sFtl-1/PlGF ratio in urine seem to be the most promising as screening tests. The assessment of the global load of misfolded proteins through urinary congophilia, podocyturia, and nephrinuria has also shown potential for screening and diagnosis. Studies regarding the use of proteomics and metabolomics have shown good accuracy, sensitivity, and specificity for predicting the development and severity of PE.

CONCLUSION

However, there are still many divergences in the literature, which requires future and more conclusive research to confirm the predictive role of urinary biomarkers in pregnant women with PE.

From Molecules to Imaging: Assessment of Placental Hypoxia Biomarkers in Placental Insufficiency Syndromes

Placental hypoxia poses significant risks to both the developing fetus and the mother during pregnancy, underscoring the importance of early detection and monitoring. Effectively identifying placental hypoxia and evaluating the deterioration in placental function requires reliable biomarkers. Molecular biomarkers in placental tissue can only be determined post-delivery and while maternal blood biomarkers can be measured over time, they can merely serve as proxies for placental function. Therefore, there is an increasing demand for non-invasive imaging techniques capable of directly assessing the placental condition over time. Recent advancements in imaging technologies, including photoacoustic and magnetic resonance imaging, offer promising tools for detecting and monitoring placental hypoxia. Integrating molecular and imaging biomarkers may revolutionize the detection and monitoring of placental hypoxia, improving pregnancy outcomes and reducing long-term health complications. This review describes current research on molecular and imaging biomarkers of placental hypoxia both in human and animal studies and aims to explore the benefits of an integrated approach throughout gestation.

Early increase in circulating carbonic anhydrase IX: A potential new predictive biomarker of preeclampsia

Preeclampsia (PE) is a severe complication of pregnancy. The identification of a reliable predictive biomarker could help in setting up a specific preventive strategy. To this aim, we studied carbonic anhydrase IX (CAIX) as a marker of hypoxia (a pathway involved in PE pathogenesis) and compared the diagnostic accuracy of CAIX to that of the validated biomarker sFlt1/PlGF ratio. Fifteen women with overt PE and 38 women at a risk of developing PE, sampled at different time intervals during gestation (a total of 82 plasma samples collected), were enrolled and underwent the CAIX measurement. CAIX levels significantly increased (p < .001) before the onset of the disease in women (25% of the total number) who later on developed PE when compared to women who did not, starting from 28th gestational week. The best CAIX cut-off of 68.268 pg/mL yielded a sensitivity of 100%, a specificity of 81.82%, and an AUC value of .9221. In our pilot study, when compared to the sFlt1/PlGF ratio, CAIX performed better in predicting PE before the clinical onset. Furthermore when implemented as CAIX/PlGF ratio, showed up to be comparable in the identification of women with overt early PE. In conclusion, CAIX could represent an effective predictive biomarker of PE, and larger studies are mandatory to validate this finding.

Enhanced SHP-1 Expression in Podocyturia Is Associated with Kidney Dysfunction in Patients with Diabetes

Background

Diabetic kidney disease (DKD) remains the leading cause of end stage kidney disease worldwide. Despite significant advances in kidney care, there is a need to improve noninvasive techniques to predict the progression of kidney disease better for patients with diabetes. After injury, podocytes are shed in urine and may be used as a biologic tool. We previously reported that SHP-1 is upregulated in the kidney of diabetic mice, leading to podocyte dysfunction and loss. Our objective was to evaluate the expression levels of SHP-1 in urinary podocytes and kidney tissues of patients with diabetes.

Methods

In this prospective study, patients with and without diabetes were recruited for the quantification of SHP-1 in kidney tissues, urinary podocytes, and peripheral blood monocytes. Immunochemistry and mass spectrometry techniques were applied for kidney tissues. Urinary podocytes were counted, and expression of SHP-1 and podocyte markers were measured by quantitative PCR.

Results

A total of 66 participants (diabetic n=48, nondiabetic n=18) were included in the analyses. Diabetes was associated with increased SHP-1 expression in kidney tissues (P=0.03). Nephrin and podocin mRNA was not significantly increased in urinary podocytes from patients with diabetes compared with those without diabetes, whereas levels of SHP-1 mRNA expression significantly correlated with HbA1c and estimated glomerular filtration rate (eGFR). Additionally, follow-up (up to 2 years post recruitment) evaluation indicated that SHP-1 mRNA expression continued to increase with eGFR decline.

Conclusions

Levels of SHP-1 in urinary podocytes may serve as an additional marker of glomerular disease progression in this population.