Pathophysiological Biomarkers Research Articles

Pharmacodynamic effects of semorinemab on plasma and CSF biomarkers of Alzheimer's disease pathophysiology.

Semorinemab, an anti-tau monoclonal antibody, was assessed in two Phase II trials for Alzheimer's disease (AD). Plasma and cerebrospinal fluid (CSF) biomarkers provided insights into the drug's potential mechanism of action. Qualified assays were used to measure biomarkers of tau, amyloidosis, glial activity, neuroinflammation, synaptic function, and neurodegeneration from participant samples in Tauriel (NCT03289143) and Lauriet (NCT03828747) Phase II trials. Plasma phosphorylated Tau 181 (pTau181) and CSF chitinase-3-like protein 1 (YKL-40) increased following semorinemab treatment in both studies. In Lauriet, increasing plasma glial fibrillary protein (GFAP) concentrations stabilized with semorinemab, while this was not observed in Tauriel. Other AD pathophysiology biomarkers showed no consistent response to semorinemab. Increases in CSF YKL-40 suggest that semorinemab may stimulate microglia activation in the presence of AD-associated Tau pathology, but not in healthy controls. Stabilization of plasma GFAP in Lauriet indicates a possible impact on reactive gliosis in mild-to-moderate AD. Tauriel ClinicalTrials.gov Identifier: NCT03289143. Lauriet ClinicalTrials.gov Identifier: NCT03828747. Phase 1 ClinicalTrials.gov Identifier: NCT02820896. AD pathophysiology biomarkers were measured to assess the mechanism of action. Semorinemab increased CSF YKL-40 in participants with AD but not in healthy controls. Semorinemab possibly stabilized plasma GFAP in the Lauriet trial. Semorinemab treatment may activate microglia and moderate reactive gliosis.

MicroRNA-Targeted Gene Regulation in Salivary Gland Tissue of De Novo Parkinson's Disease Patients.

Although α-synucleinopathy has been confirmed in the submandibular gland (SMG) tissue of Parkinson's disease (PD) patients, in-depth disease-related molecular research, such as tissue-specific transcriptional signals, has not been performed. In the present study, disease-relevant tissue-specific transcriptional signals in SMG tissue from PD patients were investigated to identify potential diagnostic, prognostic, and pathophysiologic biomarkers. Here, seven de novo drug-naïve PD patients and six age- and sex-matched individuals without neurological or psychological diseases were enrolled. Total RNA sequencing (RNA-seq) and total small RNA-seq (smRNA-seq) were performed on SMG tissue and blood samples, with 26 RNA-seq and 26 smRNA-seq samples used for the final analysis. Differentially expressed genes (DEGs) and microRNAs in SMG tissue and blood from PD patients were obtained and their functional integration and interaction network were analyzed. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that the DEGs interacted with cytokine-, inflammation-, and immune-related pathways. Synphilin-1 expression was significantly downregulated in SMG tissue of PD patients, and α-synuclein expression did not significantly differ between PD patients and controls in either SMG tissue or blood. Fifteen tissue-specific miRNA signals in SMG tissue were identified that showed better diagnostic ability compared with those in blood samples. The correlation between DEGs and environmental factors appeared altered in PD patients. The results indicated the DEGs and microRNA signatures identified in SMG tissue may be promising diagnostic and prognostic biomarkers. These molecular insights offer potential avenues for the development of novel therapeutic strategies targeting the underlying disease mechanisms in PD patients.

Neuronal plasma biomarkers in acute ischemic stroke.

Early imaging-based detection of acute ischemic stroke (AIS) has improved in the era of reperfusion therapy. Despite of this, prognosis of outcome after AIS remains a challenge. Therefore, parameters that support clinical decision making are sought. Blood-based biomarkers have the potential to provide valuable information in addition to the established prognostic factors. Neuronal biomarkers of acute or degenerative neuronal injury have shown to be reliably detected in plasma. These biomarkers are well-established in neurodegenerative pathology, such as Alzheimer's disease. In this study, we explored the association between stroke diameter and plasma biomarkers for neuronal injury and tau pathophysiology (brain-derived tau [BD-tau], phosphorylated-tau-217 [p-tau21] and neurofilament light [NfL]) in patients (n = 193) admitted to the acute ward, Akershus University Hospital. All patients received a final diagnosis of AIS, transient ischemic attack or stroke mimics. Blood samples were obtained the day after admission. We find that levels of BD-tau (p = .004) and NfL (p = .011) were higher after AIS than in patients with stroke mimics. The cortical stroke diameter correlated with BD-tau (tau-b = 0.64, p < .001) and p-tau217 (tau-b = 0.36, p = .003). Linear regression confirmed BD-tau to be the strongest variable associated with stroke diameter, pointing to the potential clinical value of plasma BD-tau in outcome prediction after AIS.

Association of oxidative stress and inflammatory metabolites with Alzheimer’s disease cerebrospinal fluid biomarkers in mild cognitive impairment

BackgroundIsoprostanes and prostaglandins are biomarkers for oxidative stress and inflammation. Their role in Alzheimer's disease (AD) pathophysiology is yet unknown. In the current study, we aim to identify the association of isoprostanes and prostaglandins with the Amyloid, Tau, Neurodegeneration (ATN) biomarkers (Aβ-42, p-tau, and t-tau) of AD pathophysiology in mild cognitive impairment (MCI) subjects.MethodsTargeted metabolomics profiling was performed using liquid chromatography-mass spectrometry (LCMS) in 147 paired plasma-CSF samples from the Ace Alzheimer Center Barcelona and 58 CSF samples of MCI patients from the Mannheim/Heidelberg cohort. Linear regression was used to evaluate the association of metabolites with CSF levels of ATN biomarkers in the overall sample and stratified by Aβ-42 pathology and APOE genotype. We further evaluated the role of metabolites in MCI to AD dementia progression.ResultsIncreased CSF levels of PGF2α, 8,12-iso-iPF2α VI, and 5-iPF2α VI were significantly associated (False discovery rate (FDR) < 0.05) with higher p-tau levels. Additionally, 8,12-iso-iPF2α VI was associated with increased total tau levels in CSF. In MCI due to AD, PGF2α was associated with both p-tau and total tau, whereases 8,12-iso-iPF2α VI was specifically associated with p-tau levels. In APOE stratified analysis, association of PGF2α with p-tau and t-tau was observed in only APOE ε4 carriers while 5-iPF2α VI showed association with both p-tau and t-tau in APOE ε33 carriers. CSF levels of 8,12- iso-iPF2α VI showed association with p-tau and t-tau in APOE ε33/APOE ε4 carriers and with t-tau in APOE ε3 carriers. None of the metabolites showed evidence of association with MCI to AD progression.ConclusionsOxidative stress (8,12-iso-iPF2α VI) and inflammatory (PGF2α) biomarkers are correlated with biomarkers of AD pathology during the prodromal stage of AD and relation of PGF2α with tau pathology markers may be influenced by APOE genotype.

Prefrontal Oscillatory Slowing in Early-Course Schizophrenia Is Associated With Worse Cognitive Performance and Negative Symptoms: A Transcranial Magnetic Stimulation-Electroencephalography Study

BackgroundAbnormalities in dorsolateral prefrontal cortex (DLPFC) oscillations are neurophysiological signatures of schizophrenia thought to underlie its cognitive deficits. Transcranial magnetic stimulation with electroencephalography (TMS-EEG) provides a measure of cortical oscillations unaffected by sensory relay functionality and/or patients’ level of engagement, which are important confounding factors in schizophrenia. Previous TMS–EEG work showed reduced fast, gamma-range oscillations and a slowing of the main DLPFC oscillatory frequency, or natural frequency, in chronic schizophrenia. However, it is unclear whether this DLPFC natural frequency slowing is present in early-course schizophrenia (EC-SCZ) and is associated with symptom severity and cognitive dysfunction. MethodsWe applied TMS–EEG to the left DLPFC in 30 individuals with EC-SCZ and 28 healthy control participants. Goal-directed working memory performance was assessed using the AX–Continuous Performance Task. The EEG frequency with the highest cumulative power at the stimulation site, or natural frequency, was extracted. We also calculated the local relative spectral power as the average power in each frequency band divided by the broadband power. ResultsCompared with the healthy control group, the EC-SCZ group had reduced DLPFC natural frequency (p = .0000002, Cohen’s d = −2.32) and higher DLPFC beta-range relative spectral power (p = .0003, Cohen’s d = 0.77). In the EC-SCZ group, the DLPFC natural frequency was inversely associated with negative symptoms. Across all participants, the beta band relative spectral power negatively correlated with AX–Continuous Performance Task performance. ConclusionsDLPFC oscillatory slowing is an early pathophysiological biomarker of schizophrenia that is associated with its symptom severity and cognitive impairments. Future work should assess whether noninvasive neurostimulation, including repetitive TMS, can ameliorate prefrontal oscillatory deficits and related clinical functions in patients with EC-SCZ.

The true extent of eosinophil involvement in disease is unrecognized: the secret life of dead eosinophils.

Eosinophil-mediated pathophysiology is tissue destructive and tissue altering with proinflammatory, prothrombotic, and profibrotic effects. The distinctive morphology of an eosinophil reveals a cytoplasm chockfull of unique granules, and the granule proteins have numerous toxic effects on cells, tissues, and organs. Eosinophils are not found in most human tissues, and eosinophil involvement in diseased tissues generally is identified by cell infiltration on histopathologic examination. However, eosinophils characteristically lose their structural integrity and deposit granules and granule proteins at sites of inflammation. Hence, their participation in tissue damage may be underrecognized or entirely overlooked. The eosinophil major basic protein 1 is a toxic granule protein and, when deposited, persists in tissues. Major basic protein 1 deposition can be regarded as a footprint of eosinophil activity. Analyses of numerous eosinophil-related diseases have demonstrated clear-cut evidence of major basic protein 1 deposition in affected tissues where eosinophils were not recognized by hematoxylin and eosin tissue staining and light microscopy. Eosinophil granule protein deposition, as exemplified by localization of major basic protein 1, especially when disproportionately greater than cellular infiltration, emerges as a biomarker of hidden eosinophil-related pathophysiology. Consequently, current assessments of recognized eosinophils may vastly underestimate their role in disease.

Epigenetic and biological age acceleration in children with atopic dermatitis

BackgroundAtopic dermatitis is a chronic inflammatory skin disease resulting from the complex interplay of genetic and environmental factors, meriting exploration using temporally-dynamic biomarkers. DNA methylation-based algorithms have been trained to accurately estimate biological age, and deviation of predicted age from true age (epigenetic age acceleration) has been implicated in several inflammatory diseases, including asthma. ObjectiveTo determine the role of epigenetic and biological aging, telomere length, and epigenetically-inferred abundance of seven inflammatory biomarkers in atopic dermatitis. MethodsWe performed DNA methylation-based analyses in a pediatric atopic dermatitis cohort (n=24, mean age 2.56±0.28y) and age-matched healthy subjects (n=24, mean age 2.09±0.15y) derived from blood, using five validated algorithms that assess epigenetic (Horvath, Skin&Blood) and biological age (PhenoAge, GrimAge), telomere length (TelomereLength), and inflammatory biomarker levels. ResultsEpigenetic and biological age, but not telomere length, were accelerated in atopic dermatitis patients for four algorithms: Horvath (+0.88 years; 95%CI 0.33-1.4; p=2.3x10-3), Skin&Blood (+0.95 years; 95%CI 0.67-1.2; p=1.8x10-8), PhenoAge (+8.2 years; 95%CI 3.4-13.0; p=1.3x10-3), and GrimAge (+1.8 years 95%CI 0.22-3.3; p=0.026). Moreover, patients had increased levels of beta-2-microglobulin (+47,584.4 ng/ml; p=0.029), plasminogen activation inhibitor 1 (+3,432.9 ng/ml; p=1.1x10-5) and cystatin C (+31,691 ng/ml; p=4.0x10-5), while levels of tissue inhibitor metalloproteinase 1 (-370.7 ng/ml; p=7.5x10-4) were decreased versus healthy subjects. ConclusionDNA methylation changes associated with epigenetic and biological aging, and inflammatory proteins appear early in life in pediatric atopic dermatitis and may be relevant clinical biomarkers of pathophysiology.

Expression Patterns of miRNAs in Egyptian Children with ADHD: Clinical Study with Correlation Analysis

ADHD has huge knowledge gaps concerning its etiology. MicroRNAs (miRNAs) provide promising diagnostic biomarkers of human pathophysiology and may be a novel therapeutic option. The aim was to investigate the levels of miR-34c-3p, miR-155, miR-138-1, miR-296-5p, and plasma brain-derived neurotrophic factor (BDNF) in a group of children with ADHD compared to neurotypicals and to explore correlations between these measures and some clinical data. The participants were children with ADHD in Group I (N = 41; age: 8.2 ± 2) and neurotypical ones in Group II (N = 40; age: 8.6 ± 2.5). Group I was subjected to clinical examination, the Stanford Binet intelligence scale-5, the preschool language scale, and Conner’s parent rating scale-R. Measuring the expression levels of the miRNAs was performed by qRT-PCR for all participants. The BDNF level was measured by ELISA. The lowest scores on the IQ subtest were knowledge and working memory. No discrepancies were noticed between the receptive and expressive language ages. The highest scores on the Conner’s scale were those for cognitive problems. Participants with ADHD exhibited higher plasma BDNF levels compared to controls (p = 0.0003). Expression patterns of only miR-34c-3p and miR-138-1 were downregulated with significant statistical differences (p˂0.01). However, expression levels of miR-296-5p showed negative correlation with the total scores of IQ (p = 0.03). MiR-34c-3p, miR-138-1, while BDNF showed good diagnostic potential. The downregulated levels of miR-34c-3p and miR-138-1, together with high BDNF levels, are suggested to be involved in the etiology of ADHD in Egyptian children. Gender differences influenced the expression patterns of miRNAs only in children with ADHD.

Plasma p-tau212 antemortem diagnostic performance and prediction of autopsy verification of Alzheimer’s disease neuropathology

Blood phosphorylated tau (p-tau) biomarkers, including p-tau217, show high associations with Alzheimer’s disease (AD) neuropathologic change and clinical stage. Certain plasma p-tau217 assays recognize tau forms phosphorylated additionally at threonine-212, but the contribution of p-tau212 alone to AD is unknown. We developed a blood-based immunoassay that is specific to p-tau212 without cross-reactivity to p-tau217. Here, we examined the diagnostic utility of plasma p-tau212. In five cohorts (n = 388 participants), plasma p-tau212 showed high performances for AD diagnosis and for the detection of both amyloid and tau pathology, including at autopsy as well as in memory clinic populations. The diagnostic accuracy and fold changes of plasma p-tau212 were similar to those for p-tau217 but higher than p-tau181 and p-tau231. Immunofluorescent staining of brain tissue slices showed prominent p-tau212 reactivity in neurofibrillary tangles that co-localized with p-tau217 and p-tau202/205. These findings support plasma p-tau212 as a peripherally accessible biomarker of AD pathophysiology.

Depressive Symptoms and Plasma Markers of Alzheimer's Disease and Neurodegeneration: A Coordinated Meta-Analysis of 8 Cohort Studies

Depressive symptoms are associated with an increased risk of Alzheimer's disease (AD). There has been a recent emergence in plasma biomarkers for AD pathophysiology, such as amyloid-beta (Aβ) and phosphorylated tau (p-tau), as well as for axonal damage (neurofilament light, NfL) and astrocytic activation (glial fibrillary acidic protein, GFAP). Hypothesizing that depressive symptoms may occur along the AD process, we investigated associations between plasma biomarkers of AD with depressive symptoms in individuals without dementia. A two-stage meta-analysis was performed on 2 clinic-based and 6 population-based cohorts (N = 7210) as part of the Netherlands Consortium of Dementia Cohorts. Plasma markers (Aβ42/40, p-tau181, NfL, and GFAP) were measured using Single Molecular Array (Simoa; Quanterix) assays. Depressive symptoms were measured with validated questionnaires. We estimated the cross-sectional association of each standardized plasma marker (determinants) with standardized depressive symptoms (outcome) using linear regressions, correcting for age, sex, education, and APOE ε4 allele presence, as well as subgrouping by sex and APOE ε4 allele. Effect estimates were entered into a random-effects meta-analysis. Mean age of participants was 71 years. The prevalence of clinically relevant depressive symptoms ranged from 1% to 22%. None of the plasma markers were associated with depressive symptoms in the meta-analyses. However, NfL was associated with depressive symptoms only in APOE ε4 carriers (β 0.11; 95% CI: 0.05-0.17). Late-life depressive symptoms did not show an association to plasma biomarkers of AD pathology. However, in APOE ε4 allele carriers, a more profound role of neurodegeneration was suggested with depressive symptoms.

Peripheral Levels of the Brain-Derived Neurotrophic Factor in Coronary Artery Disease: A Systematic Review and Meta-Analysis.

Among its functions, brain-derived neurotrophic factor (BDNF) regulates endothelial and macrophage activation, possibly playing a role in atherosclerotic plaque pathophysiology. Given contradicting reports, this study sought to investigate whether blood levels of BDNF differed between patients with coronary heart disease (CHD) and controls. We explored PubMed, Embase, Web of Science, and Cochrane Library for studies comparing BDNF blood levels in patients with CHD and controls. Random-effect meta-analysis was conducted to calculate the standardized mean differences (SMD) and 95% confidence intervals (CI). The Newcastle-Ottawa scale was used to evaluate the quality of included articles, and statistical analyses were conducted using R version 4.0.4. The final analysis comprised 12 investigations covering 1422 CHD cases and 929 controls with mean ages of 59.66±13.56 and 53.78±13.61 years, respectively. The initial analyses revealed a tendency toward low levels of BDNF in the CHD group compared with the control group (SMD= -0.41; 95% CI, -1.12 to 0.30; P=0.26). After the removal of outliers, the difference achieved statistical difference (SMD= -0.56; 95% CI, -0.93 to -0.19; P<0.01). Subgroup analysis demonstrated no significant difference between serum and plasma BDNF levels (P=0.54); however, subgroup analyses of studies investigating plasma BDNF showed that patients with CHD had significantly lower BDNF levels. Serum and plasma BDNF concentrations were considerably lower in patients with CHD than in healthy controls. Further studies of higher quality are required on the potential role of BDNF as a biomarker of CHD pathophysiology and severity.

Neuroimaging Methods for MRI Analysis in CSF Biomarkers Studies.

Among others, the existence of pathophysiological biomarkers such as cerebrospinal fluid (CSF) Aβ-42, t-tau, and p-tau preceding the onset of Alzheimer's disease (AD) symptomatology has shifted the conceptualization of AD as a continuum. In addition, magnetic resonance imaging (MRI) enables the study of structural and functional cross-sectional correlates and longitudinal changes in vivo, and therefore, the combination of CSF data and imaging analyses emerges as a synergistic approach to understand the structural correlates related with specific AD-related biomarkers. In this chapter, we describe the methods used in neuroimaging that will allow researchers to combine data on CSF metabolites with imaging analyses.

Neurovascular Hypoxia Trajectories Assessed by Photoacoustic Imaging in a Murine Model of Cardiac Arrest and Resuscitation.

Cardiac arrest is a common cause of death annually mainly due to postcardiac arrest syndrome that leads to multiple organ global hypoxia and dysfunction after resuscitation. The ability to quantify vasculature changes and tissue oxygenation is crucial to adapt patient treatment in order to minimize major outcomes after resuscitation. For the first time, we applied high-resolution ultrasound associated with photoacoustic imaging (PAI) to track neurovascular oxygenation and cardiac function trajectories in a murine model of cardiac arrest and resuscitation. We report the preservation of brain oxygenation is greater compared to that in peripheral tissues during the arrest. Furthermore, distinct patterns of cerebral oxygen decay may relate to the support of vital brain functions. In addition, we followed trajectories of cerebral perfusion and cardiac function longitudinally after induced cardiac arrest and resuscitation. Volumetric cerebral oxygen saturation (sO2) decreased 24 h postarrest, but these levels rebounded at one week. However, systolic and diastolic cardiac dysfunction persisted throughout and correlated with cerebral hypoxia. Pathophysiologic biomarker trends, identified via cerebral PAI in preclinical models, could provide new insights into understanding the pathophysiology of cardiac arrest and resuscitation.

Dietary Behaviors and Social Determinants of Health Among Adults Living with Sickle Cell Disease

Background: Social determinants of health (SDoH) may impact outcomes in sickle cell disease (SCD), and recent literature reports that particular SDoH, such as food insecurity and housing insecurity, may impact diet choices for individuals with SCD. Notably, health outcomes in SCD are linked to diet choices through increased protein and caloric needs, and through nutrients, such as polyphenols, omega fatty acids and micronutrients, which are involved in SCD pathophysiology. The connection between SDoH and diet quality may occur through multiple pathways including access to food, affordability, chronic pain and psychosocial factors at the individual and family level. Importantly, the impact of this connection may relate to outcomes such as pain frequency, hospitalizations, and SCD pathophysiologic biomarkers, such as inflammation. Study Design and Methods: The Diet and SCD Study (NCT: 05170412) is an observational mixed-methods study initiated in 2021 at the National Institutes of Health Clinical Center (NIH CC) in Bethesda MD with a target sample of 75 adults living with SCD in the United States. The purpose of the study is to evaluate associations between SDoH (food insecurity, neighborhood food access, education, employment, healthcare access), dietary intake, and population health related outcomes among adults living with SCD. Study inclusion criteria consists of adults (≥18 years of age) residing within the United States at the time of screening who have a confirmed diagnosis of sickle cell disease with any genotype, and are not hospitalized at the time of enrollment. To ensure participation from adults in diverse regions of the United States, the study has a hybrid design of in-person and telehealth procedures. In-person protocol visits are conducted at the NIH CC. The CC clinical visit includes a clinical assessment, anthropometric measurements, phlebotomy, as well as monitored/proctored electronic surveys that collect SDoH and disease severity variables. The telehealth protocol visit includes a virtual clinical assessment, phlebotomy at a local laboratory center, as well as the same monitored/proctored electronic surveys completed by CC clinical visit participants. A dietary behavior semi-structured interview is conducted at both the CC clinical visit and telehealth protocol visit to garner participants' personal stories related to food choices and diet. Laboratory variables include SCD disease specific markers, amino acid levels, and measurement of inflammatory cytokine markers. All participants undergo two unannounced phone-administered 24-hour dietary recall interviews with trained NIH nutrition staff to measure recent dietary intake. Data from 24-hour recall interviews are used to determine fluid, caloric, macro and micronutrient, and polyphenol intake. Usual dietary intake of foods of potentially related to SCD pathophysiology (cruciferous vegetables and thiocyanate-rich foods) is measured through self-administered electronic 12-month food frequency questionnaires. Primary objectives are to evaluate social determinants of health related to food security and access relevant to disease severity among adults living with sickle cell disease in the U.S. Secondary outcomes are to evaluate the association of dietary quality, specific dietary nutrient intake and serum levels, including amino acids and polyphenols, with disease severity. Tertiary outcomes include evaluating inflammatory and glucometabolic biomarkers with measures of social determinants of health. When completed, the Diet and SCD study will provide important information on the associations between SDoH, dietary quality, inflammatory biomarkers and disease severity for adults living with SCD and provide initial data for future cohort and intervention studies.

Outlier Analysis for Acute Blood Biomarkers of Moderate and Severe Traumatic Brain Injury.

Blood biomarkers have been studied to improve the clinical assessment and prognostication of patients with moderate-severe traumatic brain injury (mo/sTBI). To assess their clinical usability, one needs to know of potential factors that might cause outlier values and affect clinical decision making. In a prospective study, we recruited patients with mo/sTBI (n = 85) and measured the blood levels of eight protein brain pathophysiology biomarkers, including glial fibrillary acidic protein (GFAP), S100 calcium-binding protein B (S100B), neurofilament light (Nf-L), heart-type fatty acid-binding protein (H-FABP), interleukin-10 (IL-10), total tau (T-tau), amyloid β40 (Aβ40) and amyloid β42 (Aβ42), within 24 h of admission. Similar analyses were conducted for controls (n = 40) with an acute orthopedic injury without any head trauma. The patients with TBI were divided into subgroups of normal versus abnormal (n = 9/76) head computed tomography (CT) and favorable (Glasgow Outcome Scale Extended [GOSE] 5-8) versus unfavorable (GOSE <5) (n = 38/42, 5 missing) outcome. Outliers were sought individually from all subgroups from and the whole TBI patient population. Biomarker levels outside Q1 - 1.5 interquartile range (IQR) or Q3 + 1.5 IQR were considered as outliers. The medical records of each outlier patient were reviewed in a team meeting to determine possible reasons for outlier values. A total of 29 patients (34%) combined from all subgroups and 12 patients (30%) among the controls showed outlier values for one or more of the eight biomarkers. Nine patients with TBI and five control patients had outlier values in more than one biomarker (up to 4). All outlier values were > Q3 + 1.5 IQR. A logical explanation was found for almost all cases, except the amyloid proteins. Explanations for outlier values included extremely severe injury, especially for GFAP and S100B. In the case of H-FABP and IL-10, the explanation was extracranial injuries (thoracic injuries for H-FABP and multi-trauma for IL-10), in some cases these also were associated with abnormally high S100B. Timing of sampling and demographic factors such as age and pre-existing neurological conditions (especially for T-tau), explained some of the abnormally high values especially for Nf-L. Similar explanations also emerged in controls, where the outlier values were caused especially by pre-existing neurological diseases. To utilize blood-based biomarkers in clinical assessment of mo/sTBI, very severe or fatal TBIs, various extracranial injuries, timing of sampling, and demographic factors such as age and pre-existing systemic or neurological conditions must be taken into consideration. Very high levels seem to be often associated with poor prognosis and mortality (GFAP and S100B).

Hepatokines as Biomarkers of Obesity-Associated Liver Pathophysiology: Deciphering Advances in Basic and Clinical Aspects

Hepatokines are specialized secretory proteins of the liver that play pivotal role in regulation of metabolic homeostasis as well as ensure crosstalk of liver to other organs. In recent years, the correlation of hepatokines and hepatic diseases has been exhibited, positively. Several stimuli, particularly hepatic steatosis provoke dysregulation in metabolic homeostasis and subsequently, pathogenesis of liver diseases that influence expression and release of hepatokines. In this review, we have interlinked the association of hepatic steatosis, a hallmark of obesity, to liver and liver-derived hepatokines. Furthermore, we summarized briefly the impact of several etiologically and epidemiologically important hepatokines, including Fetuin-A, fibroblast growth factor-21 (FGF-21), selenoprotein P, sexual hormone binding globulin (SHBG), angiopoietin like 4 (ANGPTL4) and leukocyte cell-derived chemotaxin (LECT2), in health and disease. Such hepatokines could serve as non-invasive biomarkers of early stages of liver pathogenesis and might contribute in improving patient safety profile for screening purposes and expediting drug development.

Albumin and Associated Biomarkers in Severe Neuropsychiatric Disorders: Acute-Phase Schizophrenia and Bipolar Disorder.

Inflammation is relevant to the pathophysiology of severe neuropsychiatric disorders, schizophrenia (SCZ) and bipolar disorders (BD). Multiple pathophysiological biomarkers are valuable for the study of inflammatory processes. This study investigated albumin-related biomarkers in SCZ and BD to explore their roles in disease. A total of 5,577 SCZ, 3442 BD-manic (BD-M) and 1405 BD-depression (BD-D) in acute stage and 5000 health controls (HCs) were enrolled. The differences in these biomarker levels among different groups were compared, and the contributing factors for the occurrence of SCZ, BD, and subgroups of BD were analyzed. Both SCZ and BD exhibit lower prognostic nutritional index (PNI), but higher neutrophil percentage-to-albumin ratio (NPAR) and creatinine-albumin ratio (CRA) compared with HC. Compared with BD-D, BD-M had higher NPAR and platelet-to-albumin ratio (PAR) and lower CRA. In logistic regression, lower prognostic nutritional index (PNI) and higher CRA were associated with both SCZ and BD, while higher NPAR was associated with BD. In the subgroup of BD, higher NPAR, CRA and lower PNI were associated with BD-M; lower PAR, PNI and higher CRA were associated with BD-D. Our study reaffirmed the role of inflammation in the pathophysiology of SCZ and BD. Diagnostic value has been demonstrated in NPAR, PAR, PNI and CRA for BD and SCZ.

Re-investigation of functional gastrointestinal disorders utilizing a machine learning approach

BackgroundFunctional gastrointestinal disorders (FGIDs), as a group of syndromes with no identified structural or pathophysiological biomarkers, are currently classified by Rome criteria based on gastrointestinal symptoms (GI). However, the high overlap among FGIDs in patients makes treatment and identifying underlying mechanisms challenging. Furthermore, disregarding psychological factors in the current classification, despite their approved relationship with GI symptoms, underlines the necessity of more investigation into grouping FGID patients. We aimed to provide more homogenous and well-separated clusters based on both GI and psychological characteristics for patients with FGIDs using an unsupervised machine learning algorithm.MethodsBased on a cross-sectional study, 3765 (79%) patients with at least one FGID were included in the current study. In the first step, the clustering utilizing a machine learning algorithm was merely executed based on GI symptoms. In the second step, considering the previous step's results and focusing on the clusters with a diverse combination of GI symptoms, the clustering was re-conducted based on both GI symptoms and psychological factors.ResultsThe first phase clustering of all participants based on GI symptoms resulted in the formation of pure and non-pure clusters. Pure clusters exactly illustrated the properties of most pure Rome syndromes. Re-clustering the members of the non-pure clusters based on GI and psychological factors (i.e., the second clustering step) resulted in eight new clusters, indicating the dominance of multiple factors but well-discriminated from other clusters. The results of the second step especially highlight the impact of psychological factors in grouping FGIDs.ConclusionsIn the current study, the existence of Rome disorders, which were previously defined by expert opinion-based consensus, was approved, and, eight new clusters with multiple dominant symptoms based on GI and psychological factors were also introduced. The more homogeneous clusters of patients could lead to the design of more precise clinical experiments and further targeted patient care.

Longitudinal MicroRNA Signature of Conversion to Psychosis.

The emergence of psychosis in ultra-high-risk subjects (UHR) is influenced by gene-environment interactions that rely on epigenetic mechanisms such as microRNAs. However, whether they can be relevant pathophysiological biomarkers of psychosis' onset remains unknown. We present a longitudinal study of microRNA expression, measured in plasma by high-throughput sequencing at baseline and follow-up, in a prospective cohort of 81 UHR, 35 of whom developed psychosis at follow-up (converters). We combined supervised machine learning and differential graph analysis to assess the relative weighted contribution of each microRNA variation to the difference in outcome and identify outcome-specific networks. We then applied univariate models to the resulting microRNA variations common to both strategies, to interpret them as a function of demographic and clinical covariates. We identified 207 microRNA variations that significantly contributed to the classification. The differential network analysis found 276 network-specific correlations of microRNA variations. The combination of both strategies identified 25 microRNAs, whose gene targets were overrepresented in cognition and schizophrenia genome-wide association studies findings. Interpretable univariate models further supported the relevance of miR-150-5p and miR-3191-5p variations in psychosis onset, independent of age, sex, cannabis use, and medication. In this first longitudinal study of microRNA variation during conversion to psychosis, we combined 2 methodologically independent data-driven strategies to identify a dynamic epigenetic signature of the emergence of psychosis that is pathophysiologically relevant.

Brugada Syndrome: More than a Monogenic Channelopathy.

Brugada syndrome (BrS) is an inherited cardiac channelopathy first diagnosed in 1992 but still considered a challenging disease in terms of diagnosis, arrhythmia risk prediction, pathophysiology and management. Despite about 20% of individuals carrying pathogenic variants in the SCN5A gene, the identification of a polygenic origin for BrS and the potential role of common genetic variants provide the basis for applying polygenic risk scores for individual risk prediction. The pathophysiological mechanisms are still unclear, and the initial thinking of this syndrome as a primary electrical disease is evolving towards a partly structural disease. This review focuses on the main scientific advancements in the identification of biomarkers for diagnosis, risk stratification, pathophysiology and therapy of BrS. A comprehensive model that integrates clinical and genetic factors, comorbidities, age and gender, and perhaps environmental influences may provide the opportunity to enhance patients' quality of life and improve the therapeutic approach.