Background: Preeclampsia is a multifactorial cardiovascular disorder of pregnancy. If left untreated, it can lead to severe maternal and fetal outcomes. Hence, timely diagnosis and management of preeclampsia are extremely important. Biomarkers of oxidative stress are associated with the pathogenesis of preeclampsia and therefore could be indicative of evolving preeclampsia and utilized for timely diagnosis. In this study, we conducted a systematic review and meta-analysis to determine the most reliable oxidative stress biomarkers in preeclampsia, based on their diagnostic sensitivities and specificities as well as their positive and negative predictive values. Methods: A systematic search using PubMed, ScienceDirect, ResearchGate, and PLOS databases (1900 to March 2021) identified nine relevant studies including a total of 343 women with preeclampsia and 354 normotensive controls. Results: Ischemia-modified albumin (IMA), uric acid (UA), and malondialdehyde (MDA) were associated with 3.38 (95% CI 2.23, 4.53), 3.05 (95% CI 2.39, 3.71), and 2.37 (95% CI 1.03, 3.70) odds ratios for preeclampsia diagnosis, respectively. The IMA showed the most promising diagnostic potential with the positive predictive ratio (PPV) of 0.852 (95% CI 0.728, 0.929) and negative predictive ratio (NPV) of 0.811 (95% CI 0.683, 0.890) for preeclampsia. Minor between-study heterogeneity was reported for these biomarkers (Higgins’ I² = 0–15.879%). Conclusions: This systematic review and meta-analysis identified IMA, UA, and MDA as the most promising oxidative stress biomarkers associated with established preeclampsia. IMA as a biomarker of tissue damage exhibited the best diagnostic test accuracy. Thus, these oxidative stress biomarkers should be further explored in larger cohorts for preeclampsia diagnosis. Graphical

Heart failure with preserved ejection fraction (HFpEF) accounts for around 50% of all heart failure cases. It is a heterogeneous condition with poorly understood pathogenesis. Here, we aimed to identify unique pathogenic mechanisms in acute and chronic HFpEF and hypertrophic cardiomyopathy (HCM). We performed unbiased, comprehensive proteomic analyses of plasma samples from gender- and BMI-matched patients with acute HFpEF (n = 8), chronic HFpEF (n = 9) and HCM (n = 14) using liquid chromatography–mass spectrometry. Distinct molecular signatures were observed in different HFpEF forms. Clusters of biomarkers differentially abundant between HFpEF forms were predominantly associated with microvascular inflammation. New candidate protein markers were also identified, including leucine-rich alpha-2-glycoprotein 1 (LRG1), serum amyloid A1 (SAA1) and inter-alpha-trypsin inhibitor heavy chain 3 (ITIH3). Our study is the first to apply systematic, quantitative proteomic screening of plasma samples from patients with different subtypes of HFpEF and identify candidate biomarkers for improved management of acute and chronic HFpEF and HCM.

Heart failure (HF) is the leading cause of hospitalisations worldwide, with only 35% of patients surviving the first 5 years after diagnosis. The pathogenesis of HF with preserved ejection fraction (HFpEF) is still unclear, impeding the implementation of effective treatments. FK506-binding protein like (FKBPL) and its therapeutic peptide mimetic, AD-01, are critical mediators of angiogenesis and inflammation. Thus, in this study, we investigated—for the first time—FKBPL’s role in the pathogenesis and as a biomarker of HFpEF. In vitro models of cardiac hypertrophy following exposure to a hypertensive stimulus, angiotensin-II (Ang-II, 100 nM), and/or AD-01 (100 nM), for 24 and 48 h were employed as well as human plasma samples from people with different forms of HFpEF and controls. Whilst the FKBPL peptide mimetic, AD-01, induced cardiomyocyte hypertrophy in a similar manner to Ang-II (p < 0.0001), when AD-01 and Ang-II were combined together, this process was abrogated (p < 0.01–0.0001). This mechanism appears to involve a negative feedback loop related to FKBPL (p < 0.05). In human plasma samples, FKBPL concentration was increased in HFpEF compared to controls (p < 0.01); however, similar to NT-proBNP and Gal-3, it was unable to stratify between different forms of HFpEF: acute HFpEF, chronic HFpEF and hypertrophic cardiomyopathy (HCM). FKBPL may be explored for its biomarker and therapeutic target potential in HFpEF.

Aims: Circulating biomarkers are commonly used in diagnosis and prognosis of heart failure with preserved ejection fraction (HFpEF) in clinical practice. However, the diagnostic and prognostic potential of current biomarkers in HFpEF remain unclear. Methods and results: We conducted a search of the PubMed, Web of Science, MEDLINE and SCOPUS (1900 to January 2020) databases of all diagnostic (n=1,104) and prognostic (n=53,497) biomarkers investigated in people with HFpEF. B-type natriuretic peptide (BNP) displayed satisfactory sensitivity (0.81, 95% CI: 0.76 to 0.85; I ² =0) and specificity (0.86, 95% CI: 0.82 to 0.89; I ² =16.9%) for the diagnosis of HFpEF. Natriuretic peptides (NPs), including N-terminal pro BNP (NT-proBNP) and BNP, were associated with over two-fold increased risk of mortality (NT-proBNP: HR=2.27, 95% CI: 1.69 to 3.06, I ² =87.6%; BNP: HR=3.01, 95% CI: 1.27 to 7.21, I ² =97.2%), hospitalisation (NT-proBNP: HR=3.54, 95% CI: 2.83 to 4.43, I ² =83.4%), and a composite event of both (NT-proBNP: HR=2.55, 95% CI: 2.13 to 3.05, I ² =78.1%; BNP: HR=2.28, 95% CI: 1.42 to 3.69, I ² =75.8%) in people with HFpEF. Interestingly, Galectin-3 (Gal-3) (sensitivity: 0.70, 95% CI: 0.63 to 0.75, I ² =86.7%; specificity: 0.78, 95% CI: 0.69 to 0.85, I ² =68.6%) and soluble suppression of tumorigenicity 2 (sST2) (sensitivity: 0.58, 95% CI: 0.52 to 0.64, I ² =88.1%; specificity: 0.59, 95% CI: 0.49 to 0.68, I ² =69.5%) showed limited diagnostic potential of HFpEF. Conclusion: Amongst currently available biomarkers, BNP remains the most reliable diagnostic marker of HFpEF. Although there was high heterogeneity between the studies included, BNP or NT-proBNP could also have promising prognostic potential in HFpEF.