The discovery of protein biomarkers in pre-eclampsia: the promising role of mass spectrometry

Abstract

Context: Pre-eclampsia (PE) is a common hypertensive disorder of pregnancy that substantially affects maternal and neonatal morbidity and mortality worldwide. The aetiology of the disease remains poorly understood with lack of reliable diagnostic tests. PE is a multisystem disorder so it is very unlikely that a single or a small group of biomarkers will accurately predict the disease. Mass spectrometry (MS) is indispensable analytical tool in protein analysis studies. MS-based proteomics have the ability to detect the entire protein complement to provide a useful window into a range of biological processes and allow the identification of differentially expressed proteins between samples.

Objective: The aim of this review is to summarise, discuss and evaluate the current predominant MS-based approaches applied for protein biomarker discovery. The paper also seeks to evaluate the current potential PE biomarkers described in the literature and identify issues that can guide future research.

Conclusion: MS-based proteomics studies are promising alternatives to classical hypothesis-driven approaches to discover novel biomarkers and provide new insights into the underlying phathophysiological mechanisms of PE. This should aid in the early diagnosis of PE and the understanding of the aetiology of the disease.     

The adipokine preadipocyte factor-1 is downregulated in preeclampsia and expressed in placenta

BackgroundAdipokines contribute to the development of preeclampsia (PE), a severe pregnancy complication which increases the future risk for cardiovascular and metabolic disease in both mother and newborn. Pre-adipocyte factor-1 (Pref-1) was recently introduced as a novel antiangiogenic and antiadipogenic adipokine.Material and methodsPref-1 was quantified in patients with PE (n = 51) and healthy pregnant controls (n = 51) during pregnancy, as well as 6 months after delivery (study population 1). Furthermore, Pref-1 was investigated in the immediate peripartal period and the placenta in 40 healthy pregnant women undergoing elective cesarean section (study population 2).ResultsIn study population 1, median Pref-1 serum concentrations during pregnancy were significantly lower in women with PE (0.5 μg/l) as compared to healthy pregnant controls (0.7 μg/l) (p < 0.001). Furthermore, Pref-1 serum concentrations were independently predicted by PE, leptin levels, and gestational age in this population. In both study populations, Pref-1 serum levels significantly decreased after delivery as compared to prepartal levels. Moreover, significant expression of Pref-1 was detected in placental tissue.ConclusionMaternal Pref-1 serum concentrations are significantly decreased in PE. The pathophysiological significance of this regulation needs to be studied in more detail in future experiments.     

Increasing of LDH Specific Activity and PEPCK Level Play a Role on Activation of Gluconeogenesis Pathway in Early Onset Pre-Eeclampsia Placenta

Background:Recent advancement on experiment concluded that etiology of pre-eclampsia (PE) could be explained by the "two-stage" theory. The theory of which explained that pre-eclampsia occurs due to abnormalities in spiral arteries development and release of inflammatory response. Failure of spiral arteries development, the lesion of damage could be due to ischemia-reperfusion or hypoxia-reoxygenation. Hypoxia in pre-eclamptic placenta leads to metabolic change to anaerobic in glycolysis. Lactate dehydrogenase (LDH) has important role in anaerobic glycolysis that catalyzes the conversion of lactate to pyruvate during hypoxia. On the other hand, phosphoenolpyruvate carboxy kinase (PEPCK) is merely an enzyme of gluconeogenesis. This research conduct to reveal that in early onset pre-eclampsia the placenta still hypoxic and undergoes gluconeogenesis even after delivery, through metabolic enzyme of LDH and PEPCK level.Methods:This cross-sectional study compared early onset PE (< 34 weeks) with normal term placenta. We measured LDH enzyme activity using colorimetric assay and PEPCK protein using ELISA method.Results:Result show that placental LDH specific activity was increased significantly in PE with median 2.750 (0.030 - 5.680) U/mg compared to normal term placenta 0.255 (0.032 – 1.194) U/mg (Mann-Whitney, p< 0.001). PEPCK level was significantly increased in PE 8.998 (1.737-44.914) ng/mg compared to normal term placenta 1.552 (0.741-8.832) ng/mg (Mann-Whitney, p< 0.001).Conclusion:We conclude that anaerobic glycolysis and gluconeogenesis pathway are increased in early onset PE placenta as adaptation mechanism to hypoxic condition.Key Words: Early onset preeclampsia, LDH, PEPCK, Placenta     

血清25（OH）D、IGFBP-1、STAT4与重度子痫前期患者自发性流产的关系分析

摘要 目的：探讨血清25-羟基维生素D[25（OH）D]、胰岛素生长因子结合蛋白1（IGFBP-1）、信号转导和转录激活因子4（STAT4）与重度子痫前期（PE）患者自发性流产的关系。方法：选取2020年1月到2022年12月于徐州医科大学附属医院治疗的重度PE患者150例。根据妊娠28周内是否发生自发性流产分为发生组（n=41）和未发生组（n=109）。对比两组血清25（OH）D、IGFBP-1、STAT4水平。收集两组患者的临床资料,多因素Logistic回归分析重度PE患者自发性流产的影响因素。受试者工作特征（ROC）曲线分析血清25（OH）D、IGFBP-1、STAT4水平对重度PE患者自发性流产的预测价值。结果：发生组的25（OH）D、IGFBP-1水平低于未发生组,STAT4水平高于未发生组（P<0.05）。重度PE患者自发性流产与年龄、PE发病孕周、孕前体质量指数（BMI）、分娩史、收缩压（SBP）、舒张压（DBP）、血小板计数（PLT）、肌酐（Scr）无关（P>0.05）,而与流产史、D-二聚体（D-D）、白蛋白（ALB）、同型半胱氨酸（Hcy）、纤维蛋白原有关（P<0.05）。多因素Logistic回归分析结果显示, 25（OH）D下降、IGFBP-1下降、STAT4升高、有流产史、D-D升高、ALB下降、Hcy升高均是重度PE患者自发性流产的危险因素,而纤维蛋白原升高则是重度PE患者自发性流产的保护因素（P<0.05）。血清25（OH）D、IGFBP-1、STAT4联合检测预测自发性流产的曲线下面积（AUC）为0.960,高于单独指标预测。结论：重度PE患者血清25（OH）D、IGFBP-1下降,STAT4水平升高易导致自发性流产,自发性流产的发生还与流产史、D-D、ALB、Hcy、纤维蛋白原水平等因素有关。     

Intra-individual variation of miRNA expression levels in human plasma samples

Background: Circulating miRNAs as potential non-invasive biomarkers for disease risk assessment and cancer early diagnosis have attracted increasing interest. Little information, however, is available regarding the intra-individual variation of circulating miRNA levels.

Methods: We measured expression levels of a panel of 800 miRNAs in repeated plasma samples from 51 healthy individuals that were collected 6 to 12?months apart and evaluated the intra-individual variation by the intra-class correlation coefficient (ICC).

Results: After background correction, a total of 185 miRNAs were detected in at least 10% of the plasma samples, with 69 and 28 miRNAs being detected in 50% and 90% of samples, respectively. The median ICC was 0.46 for these 185 miRNAs. Among them, 41% (75 miRNAs) had an ICC?≥?0.5, and 23% (42 miRNAs) had an ICC?≥?0.6. The ICC is higher for miRNAs with higher expression levels or higher detection rates, when compared to those with lower expression levels or lower detection rates.

Conclusions: These results suggest that common circulating miRNAs are stable over a relatively long period and can serve as reliable biomarkers for epidemiological and clinical research.     

Progress in the search for circulating biomarkers of nonalcoholic fatty liver disease

Abstract

Context: The definitive standard for the diagnosis of nonalcoholic fatty liver disease (NAFLD) is clinico-pathological correlation, but frequently the only laboratory abnormality is an elevation of serum aminotransferases.

Objective: This has resulted in the search for more specific laboratory biomarkers.

Methods: The literature was searched for novel plasma/serum markers of NAFLD.

Results: Studies reviewed here included histologically-confirmed patients presenting some stage of NAFLD and monitored one or more novel serum/plasma biomarkers.

Conclusion: The most promising application of some of these novel biomarkers for the detection and quantification of NAFLD and particularly NASH appears to be in the combination of several into diagnostic panels.     

Variation of butyrate production in the gut microbiome in type 2 diabetes patients

Background

Diabetes mellitus type 2 is a common disease that poses a challenge to the healthcare system. The disease is very often diagnosed late. A better understanding of the relationship between the gut microbiome and type 2 diabetes can support early detection and form an approach for therapies. Microbiome analysis offers a potential opportunity to find markers for this disease. Next-generation sequencing methods can be used to identify the bacteria present in the stool sample and to generate a microbiome profile through an analysis pipeline. Statistical analysis, e.g., using Student’s t-test, allows the identification of significant differences. The investigations are not only focused on single bacteria, but on the determination of a comprehensive profile. Also, the consideration of the functional microbiome is included in the analyses. The dataset is not from a clinical survey, but very extensive.

Results

By examining 946 microbiome profiles of diabetes mellitus type 2 sufferers (272) and healthy control persons (674), a large number of significant genera (25) are revealed. It is possible to identify a large profile for type 2 diabetes disease. Furthermore, it is shown that the diversity of bacteria per taxonomic level in the group of persons with diabetes mellitus type 2 is significantly reduced compared to a healthy control group. In addition, six pathways are determined to be significant for type 2 diabetes describing the fermentation to butyrate. These parameters tend to have high potential for disease detection.

Conclusions

With this investigation of the gut microbiome of persons with diabetes type 2 disease, we present significant bacteria and pathways characteristic of this disease.

     

Serial measurements of high-sensitivity cardiac troponin T after exercise stress test in stable coronary artery disease

Abstract

Objective: The aim was to assess serial measurements of high-sensitivity cardiac troponin T (hs-cTNT) post-exercise in patients with stable coronary artery disease (CAD).

Methods: Twelve patients with positive coronary angiograms (CAD positives) and 12 controls performed an exercise stress test.

Results: CAD positive had higher baseline and peak concentrations of hs-cTNT than controls. Significant increases in hs-cTNT were seen in both groups after exercise. In two-third of patients the peak in hs-cTNT was above the 99th percentile.

Conclusion: hs-cTNT is higher in patients with stable coronary disease than in controls and exceeds the diagnostic cut-off value for myocardial infarction in a majority of patients with CAD after exercise.     

Optimal sampling design to survey riparian bird populations with low detection probability

ABSTRACT

Capsule: Linear censusing and occupancy models based on fixed sampling points are alternative widely used techniques to determine bird densities in riparian ecosystems, although it cannot be always properly executed.

Aims: The aim is to assess the survey efficiency for river birds using occupancy models in contexts of impaired visibility owing to dense vegetation along the banks.

Methods: We tested whether increasing sampling periods within each survey unit (point) at occupancy models would result in increasing detection probability values. We used two approaches in order to identify the ‘best’ design for White-throated Dippers Cinclus cinclus along forested river stretches: minimizing survey effort of standard single-season site occupancy modelling and exploratory power analysis.

Results: With a detection probability of 0.26 (i.e. much lower than in previous studies), a design with 60 sites surveyed 10 min 6 times a year would be the option to survey White-throated Dippers in forested habitats if an acceptable power is required. Simulations further revealed the consistency of the results.

Conclusion: We provide guidelines to establish a cost-effective survey design for any long-term monitoring citizen-based programme of a White-throated Dipper population when detection probabilities are low. A strength and novelty of the method is to take advantage of advanced probabilistic approaches (e.g. GRTS) to select the survey sites providing, among other major interests, a spatially balanced geographic coverage.     

Ocular amphotericin B delivery by chitosan-modified nanostructured lipid carriers for fungal keratitis-targeted therapy

Abstract

Context: Fungal keratitis, a corneal fungal infection of the eye caused mainly by Candida species, has become the leading cause of blindness resulting from corneal disease in China. Present limitations in the management of ophthalmic fungal infections include the inability to provide long-term extraocular drug delivery without compromising intraocular structures and/or systemic drug exposure.

Objective: The aim of this study was to construct amphotericin B (AmB) loaded, chitosan-modified, nanostructured lipid carriers (AmB-CH-NLC) for prolonged ocular application and for the improvement of the targeted delivery of AmB to the ocular mucosa.

Materials and methods: The AmB-CH-NLC was produced by the method of emulsion evaporation-solidification at low temperature. The particle size, zeta potential, and encapsulation efficiency, drug-release behavior, and corneal penetration ability were performed in vitro and in vivo.

Results and discussion: The prepared AmB-CH-NLC nanoparticles exhibited a measured size of 185.4?nm, a zeta potential of 27.1?mV, and an entrapment efficiency of 90.9%. Sustained drug release behavior was observed in vitro. The in vivo ocular pharmacokinetic study indicated improved bioavailability of AmB-CH-NLC. The corneal penetration study showed that the AmB-CH-NLC could successfully penetrate into the cornea with no obvious irritation to the rabbits’ eyes.

Conclusion: The results support that this novel nanomedicine could be a promising system for effective ocular delivery of amphotericin B for fungal keratitis-targeted therapy.     

microRNA signatures in peripheral blood fail to detect acute cellular rejection after liver transplantation

Objective: We investigated whether microRNA signatures in whole blood samples are associated with acute cellular rejection (ACR) after liver transplantation.

Materials and methods: Blood samples were collected using Paxgene technology and analyzed by microarrays and quantitative real-time polymerase chain reaction (qRT-PCR).

Results: microRNA signatures failed to distinguish between 19 patients with ACR and 16 controls. Let-7b-5p and let-7c were upregulated in a subgroup of patients with ACR during the 6th and 7th postoperative days but failed in an independent validation of 20 patients.

Conclusion: microRNA signatures in whole blood processed by Paxgene technology are not suited for the detection of ACR after liver transplantation.     

Alterations of lymphocyte count and platelet volume precede cerebrovascular lesions in stroke-prone spontaneously hypertensive rats

Abstract

Background: Cerebral small vessel disease (CSVD) is associated with future stroke. Although pathological alteration in small vessels of patients with CSVD can be detected by neuroimaging, diagnosis of CSVD is delayed because it is an asymptomatic disease. The stroke-prone spontaneously hypertensive rat (SHRSP) show similar pathological features to human CSVD and develop stroke-related symptoms with advancing age.

Objective: We investigated the time course of haematological parameters in Wistar rats and SHRSP.

Material and Methods: Blood cells were analysed using an automated haematological analyser.

Results: SHRSP develop stroke-related symptoms including onset of neurological symptoms, decreased body weight and blood brain barrier leakage between 12 and 14?weeks of age. Lymphocyte counts were gradually decreased at 3?weeks before development of stoke-related symptoms and then were further decreased after the development of stroke-related symptoms. The both mean platelet volume and large platelet ratio gradually increased at 3?weeks before the development of stoke-related symptoms. However, although SHRSP showed more microcytic red cells than Wistar rats, the trajectories of change in erythrocyte-related parameters were similar between Wistar rats and SHRSP.

Conclusion: Our pilot study suggests that alterations of lymphocyte count and platelet volume predictive indicators for asymptomatic CSVD and symptomatic stroke in SHRSP.     

原发性肾病综合征合并血栓栓塞的临床研究

摘要 目的：肺栓塞及下肢深静脉血栓是影响肾病综合征(Nephrotic Syndrome,NS)预后的重要因素,但在其发生率以及治疗方面仍存在争议。本文将通过回顾性的病例研究对NS患者中血栓栓塞事件的发生率、危险因素以及是否需要早期干预等问题进行探讨。方法：收集上海交通大学医学院附属新华医院肾内科2014年1-12月诊断为原发性NS患者,并同时收集患者基本临床信息,血栓检查结果以及NS相关血液及尿液检查结果等在内的临床资料,采用多种统计方法分析血栓发生率及其危险因素,并进一步讨论NS患者的预防性抗凝措施。结果：NS患者下肢静脉血栓或肺栓塞的发生率均为15.4%,两种血栓同时发生的概率为9.6%。NS患者血栓事件的发生率与D-二聚体、血浆白蛋白、病程、病理类型呈明显相关,且具有统计学意义。结论：NS患者血栓栓塞的发生率与D-二聚体、血浆白蛋白、病程、病理类型呈显著相关,膜性肾病患者血栓栓塞发生率最高。如NS患者合并高危因素,建议定期筛查,综合评估后预防性抗凝。     

Intrahepatic cholestasis of pregnancy can increase the risk of metabolic disorders: A meta-analysis

BackgroundGestational diabetes mellitus (GDM) and preeclampsia (PE) are common complications during pregnancy. Studies indicated that abnormal bile acid metabolism is related to its pathogenesis. Intrahepatic cholestasis of pregnancy (ICP) is the most common pregnancy-specific liver disease, which classic symptoms include generalized pruritus that commonly and biochemical evidence of elevated bile acids. Our study aimed to explore the correlation between the ICP presence and risk of GDM, PE incident in pregnant women.MethodsA meta-analysis, which included 10 eligible studies including 17,688 ICP cases and 1,386,771 controls, was performed to assess the correlation of ICP with preeclampsia (PE) and gestational diabetes mellitus (GDM). There were 7 studies investigating the relationship between ICP and PE, and 9 studies that evaluated the relationship between ICP and GDM. All eligible studies were screened from Pubmed, Web of Science and EBSCO databases.ResultsThe results of this meta-analysis indicate that ICP significantly increase the risk for both PE (pooled odds ratio OR: 2.56 95%CI: 2.27 2.88, I2 heterogeneity = 35%, p heterogeneity = 0.16) and GDM (pooled OR: 2.28 95%CI: 1.69 3.07, I2 heterogeneity = 81%, p heterogeneity < 0.001). In the sensitivity analysis of GDM, excluding the largest heterogeneity study cannot change the result (pooled OR: 2.86 95%CI: 2.59 3.16, I2 heterogeneity = 0%, p heterogeneity = 0.56).ConclusionsThis meta-analysis shows that ICP is closely associated with ICP increased risk of PE and GDM) during pregnancy.     

A predictive microarray-based biomarker for early detection of Alzheimer’s disease intended for clinical diagnostic application

Abstract

Objective: Microarray-based signatures for clinical application are often plagued by processing variability or batch effects that compromise the robustness of the test performance.

Methods: A splice variant array-based signature for early detection of Alzheimer’s disease (AD) was developed using 315 AD or normal subjects processed in three disparate microarray batches.

Results: A modified top scoring pair classifier using the signature, is robust to batch effects and outperforms other common classifiers, with sensitivity and specificity of 88.3% (95% CI:81.2%, 93.4%) and 88.9% (95% CI:65.3%, 98.6%), respectively, on an independent cohort.

Conclusions: This splice-variant array-based signature shows promise for clinical diagnostic use in AD.     

Untargeted metabolomics: an overview of its usefulness and future potential in prenatal diagnosis

ABSTRACT

Introduction: Metabolomics opens up new avenues for biomarker discovery in different branches of medicine, including perinatology. Chromosomal aberration, preterm delivery (PTD), congenital heart defects, spina bifida, chorioamnionitis, and low birth weight are the main perinatal pathologies. Investigations using untargeted metabolomics have found the candidate metabolites for diagnostic biomarkers.

Areas covered: This review describes areas of prenatal diagnosis in which untargeted metabolomics has been used. Data on the disease, type of sample, techniques used, number of samples used in the study, and metabolites obtained including the sign of their regulation are summarized.

Expert commentary: Untargeted metabolomics is a powerful tool which can shed a new light on prenatal diagnostics. It helps to discover affected metabolic pathways what may help to reveal disease pathogenesis and propose potential biomarkers. Among others, glycerol and 2- and 3-hydroxybutyrate were proposed as markers of chromosomal aberration. Serum metabolic signature of PTD was characterized by increased lipids and decreased levels of hypoxanthine, tryptophane, and pyroglutamic acid. Lower level lipids and vitamin D3 metabolites together with increased bilirubin level in maternal serum were associated with macrosomia. However, to give a real value to those assays and allow their clinical application multicenter, large cohort validation studies are necessary.     

Soluble urokinase plasminogen activator receptor informs on the progression course after multiple injuries

Purpose: The purpose of this study is to study the use of soluble urokinase plasminogen activator receptor (suPAR) for the prognosis of multiple organ dysfunction (MOF) after multiple traumas.

Methods: Serum suPAR was measured within the first 24?h after multiple injuries in 85 patients. Measurements were repeated after 4 d or at sepsis onset.

Results: Odds ratio for trauma-associated MOF was 4.09 (p: 0.026) with admission suPAR greater than 8?ng/ml. More than 40% increases of suPAR were associated with odds ratio 9.33 (p: 0.047) for severe sepsis.

Conclusions: suPAR is a useful surrogate biomarker for development of MOF and severe sepsis after multiple traumas.     

The presence of odd-chain fatty acids in Drosophila phospholipids

ABSTRACT

Most fatty acids in phospholipids and other lipid species carry an even number of carbon atoms. Also odd-chain fatty acids (OCFAs), such as C15:0 and C17:0, are widespread throughout the living organism. However, the qualitative and quantitative profiles of OCFAs-containing lipids in living organisms remain unclear. Here, we show that OCFAs are present in Drosophila phosphatidylcholine (PC) and phosphatidylethanolamine (PE) and that their level increases in accordance with progression of growth. Furthermore, we found that food-derived propionic acid/propanoic acid (C3:0) is utilized for production of OCFA-containing PC and PE. This study provides the basis for understanding in vivo function of OCFA-containing phospholipids in development and lipid homeostasis.     

Affinity enrichment for mass spectrometry: improving the yield of low abundance biomarkers

Introduction: Mass spectrometry (MS) is the premier tool for discovering novel disease-associated protein biomarkers. Unfortunately, when applied to complex body fluid samples, MS has poor sensitivity for the detection of low abundance biomarkers (?10 ng/mL), derived directly from the diseased tissue cells or pathogens.

Areas covered: Herein we discuss the strengths and drawbacks of technologies used to concentrate low abundance analytes in body fluids, with the aim to improve the effective sensitivity for MS discovery. Solvent removal by dry-down or dialysis, and immune-depletion of high abundance serum or plasma proteins, is shown to have disadvantages compared to positive selection of the candidate biomarkers by affinity enrichment. A theoretical analysis of affinity enrichment reveals that the yield for low abundance biomarkers is a direct function of the binding affinity (Association/Dissociation rates) used for biomarker capture. In addition, a high affinity capture pre processing step can effectively dissociate the candidate biomarker from partitioning with high abundance proteins such as albumin.

Expert commentary: Properly designed high affinity capture materials can enrich the yield of low abundance (0.1–10 picograms/mL) candidate biomarkers for MS detection. Affinity capture and concentration, as an upfront step in sample preparation for MS, combined with MS advances in software and hardware that improve the resolution of the chromatographic separation can yield a transformative new class of low abundance biomarkers predicting disease risk or disease latency.     

“Filling a gap: knowledge in health related science for middle school students in formal and informal contexts

ABSTRACT

Background: Recent studies shows lack of knowledge concerning health literacy relatively microorganism/disease and the correct use of antibiotics. These facts lead to the spreading of resistant strains bacteria.

Aims: The overarching goals of this study were a) to promote health literacy predominantly in respect to microorganism/disease, diseases transmission, antibiotic target and adequate antibiotic use; b) to show the importance of the transmission of health information in different environments; c) to motivate students for science research.

Methods: Students’ knowledge was evaluated with a survey instrument. Responses were analyzed before and after the implementation of the activity. The activity consists of an interactive lecture, slide show presentation and some practical activities. The sample includes 25 Portuguese students, 13–17 years old who attended the activity in Palácio de Cristal (Porto) and 66 students from D. Maria II School, V.N. Famalicão.

Results: In this study, significant increase in knowledge about all the topics evaluated were observed both in formal and informal environments between the pre and post-test; however the best results were detected in informal contexts.

Conclusion: The findings showed the importance of the implementation of scientific activities to middle-school students. This experience was valuable and helped to improve student knowledge on heath topics.