Copeptin associates with major adverse cardiovascular events in patients on maintenance hemodialysis.

BACKGROUND: End-stage renal disease (ESRD) necessitating hemodialysis pose substantial cardiovascular risks, with cardiovascular disease (CVD) as a leading cause of mortality. Biomarkers like copeptin have emerged as potential indicators of cardiovascular stress and prognosis in CKD populations. OBJECTIVE: This study aimed to assess the prognostic value of copeptin in predicting major adverse cardiovascular events (MACEs) among hemodialysis patients, alongside traditional cardiac biomarkers. METHODS: ESRD patients undergoing maintenance hemodialysis were enrolled. Copeptin levels were measured, and patients were followed for MACEs, defined as cardiovascular deaths, myocardial infarction, stroke, or heart failure-related hospitalizations. Cox proportional-hazards models were used to evaluate the association between copeptin and outcomes, adjusting for relevant covariates. RESULTS: Among 351 patients followed for a median of 22.7 months, elevated copeptin levels were significantly associated with an increased risk of MACEs (HR 1.519, 95 % CI 1.140 to 2.023; p = 0.00425). Copeptin demonstrated predictive capability across multiple statistical tests (Log-rank p = 0.024; Gehan p < 0.001; Tarone-Ware p < 0.001; Peto-Peto p = 0.027), although significance was attenuated in pairwise comparisons post-adjustment for multiple testing. Combining copeptin with NT-proBNP or hs-cTnT further enhanced risk stratification for MACEs. CONCLUSION: Elevated copeptin levels independently predict adverse cardiovascular outcomes in hemodialysis patients. Integrating copeptin with traditional cardiac biomarkers may refine risk stratification and guide personalized therapeutic strategies in this high-risk population.

Diagnostic Utility of Copeptin in Pediatric Patients with Polyuria-Polydipsia Syndrome: A Systematic Review and Meta-Analysis.

Pediatric patients with polyuria polydipsia syndrome (PPS) represent a diagnostic challenge for clinicians because of the technical difficulties in performing the gold standard water deprivation test (WDT). Copeptin, a stable biomarker representing the C-terminal portion of the polypeptide chain of the antidiuretic hormone, is a reliable diagnostic tool. To assess the diagnostic accuracy of baseline copeptin dosing, arginine/hypertonic saline copeptin stimulation tests, and WDT. This study aimed to establish the diagnostic utility of copeptin in pediatric patients by distinguishing between central diabetes insipidus, nephrogenic diabetes insipidus, and primary polydipsia. Comparative and non-comparative primary studies published between January 2018 and August 2024 focusing on children were searched and included in PubMed, Cochrane Library, Web of Science, ScienceDirect, Scopus, and Google Scholar. The QUADAS-2 tool was used to assess the risk of bias and applicability. Meta-analyses used fixed effects models because of low heterogeneity and the HSROC model. Eleven studies were included with an overall low bias and no significant applicability concerns. The mean pooled sensitivity = 0.98 (95% CI: 0.936-1.025), pooled specificity = 0.947 (95% CI: 0.920-0.973), and AUC = 0.972 (95% CI: 0.952-0.992), indicating excellent diagnostic accuracy. Stimulation methods for copeptin dosing represent an effective and less invasive diagnostic test for children with PPS, and future development of standard copeptin testing protocols is needed.

Comprehensive serum glycopeptide spectra analysis to identify early-stage epithelial ovarian cancer.

Epithelial ovarian cancer (EOC) is widely recognized as the most lethal gynecological malignancy; however, its early-stage detection remains a considerable clinical challenge. To address this, we have introduced a new method, named Comprehensive Serum Glycopeptide Spectral Analysis (CSGSA), which detects early-stage cancer by combining glycan alterations in serum glycoproteins with tumor markers. We detected 1712 glycopeptides using liquid chromatography-mass spectrometry from the sera obtained from 564 patients with EOC and 1149 controls across 13 institutions. Furthermore, we used a convolutional neural network to analyze the expression patterns of the glycopeptides and tumor markers. Using this approach, we successfully differentiated early-stage EOC (Stage I) from non-EOC, with an area under the curve (AUC) of 0.924 in receiver operating characteristic (ROC) analysis. This method markedly outperforms conventional tumor markers, including cancer antigen 125 (CA125, 0.842) and human epididymis protein 4 (HE4, 0.717). Notably, our method exhibited remarkable efficacy in differentiating early-stage ovarian clear cell carcinoma from endometrioma, achieving a ROC-AUC of 0.808, outperforming CA125 (0.538) and HE4 (0.557). Our study presents a promising breakthrough in the early detection of EOC through the innovative CSGSA method. The integration of glycan alterations with cancer-related tumor markers has demonstrated exceptional diagnostic potential.

Hydrophilic materials based on hydrogel polymers for enrichment of glycopeptides from serum of colorectal cancer patients.

In this work, a composite hydrogel material consisting of chitosan-based composite hydrogel was prepared by a simple and rapid synthetic method and will be named three-dimensional (3D)-IL-COF-1@CS hydrogel. Possessing a stable 3D network structure and outstanding hydrophilicity, the novel hydrogel is capable of capturing glycopeptides. The 3D-IL-COF-1@CS hydrogel showed good sensitivity (0.1 fmol/µL) and selectivity (1:2000). In addition, 19 glycopeptides were captured in standard samples. In the analysis of human serum, 148 glycopeptides assigned to 72 glycoproteins were assayed in the serum of normal individuals, and 245 glycopeptides corresponding to 100 glycoproteins were found in the serum of colorectal cancer (CRC) patients. More importantly, several functional programs based on Gene Ontology analysis supported molecular biological processes that may be relevant to the pathogenesis of CRC, including aging, fibrinogen complex, and arylesterase activity. The low cost, simplicity, rapid synthesis, and good enrichment performance have a great future in glycoproteomics analysis and related diseases.

Copeptin's role in traumatic brain injury: The promising quest for a new biomarker.

OBJECTIVE: Traumatic brain injury (TBI) necessitates reliable biomarkers to improve patient care. This study explored copeptin as a potential biomarker in TBI and its relation to vasopressin (ADH) in such patients. METHODS: A cross-sectional study was conducted on 50 TBI patients. Exclusion criteria included specific medical conditions and recent traumatic events. Copeptin and ADH testing were performed within 30 days post-trauma. Patient data, Glasgow Coma Scale (GCS) scores, imaging results, and the need for surgical intervention were obtained from medical charts. RESULTS: Copeptin levels negatively correlated with GCS scores (ρ = - 0.313, p = 0.027), indicating a potential association with trauma severity. Copeptin levels (mean: 3.22 pmol/L, median 2.027 pmol/L, SD = 3.15) tended to be lower than those found in the normal population, suggesting possible neuroendocrine dysfunction post-TBI. ADH levels (mean: 67.93 pmol/L, median 56.474 pmol/L SD = 47.67) were higher than the normal range and associated with the need for surgery (p = 0.048). Surprisingly, copeptin and ADH levels negatively correlated (r = - 0.491; p < 0.001), potentially due to differences in degradation processes and physiological variations in TBI patients. CONCLUSION: Copeptin shows potential as a predictive biomarker for assessing TBI severity and predicting patient outcome. However, its complex relationship with ADH in TBI requires further investigation. Careful interpretation is needed due to potential variations in excretion dynamics and metabolism. Larger studies on TBI patient cohorts are essential to validate copeptin as a reliable biomarker and improve patient care in TBI.

Novel Plasma Biomarkers Associated with Future Peripheral Atherosclerotic Disease and Abdominal Aortic Aneurysm-Insights from Contemporary Prospective Studies from the Malmö Diet and Cancer Study.

INTRODUCTION: The potential utility of inflammatory and hemodynamic plasma biomarkers for the prediction of incident lower extremity arterial disease (LEAD), carotid artery stenosis (CAS), isolated atherosclerotic disease without concomitant abdominal aortic aneurysm (AAA), and isolated AAA without concomitant atherosclerotic disease has not yet been integrated in clinical practice. The main objective of this prospective study was to find predictive plasma biomarkers for cardiovascular disease and to evaluate differences in plasma biomarker profiles between asymptomatic and symptomatic CAS, as well as between isolated atherosclerotic disease and isolated AAA. METHODS: Blood samples collected at baseline from participants in the prospective Malmö Diet and Cancer study (MDCS) cardiovascular cohort (n = 5550 middle-aged individuals; baseline 1991-1994) were used for plasma biomarker analysis. Validation of each incident cardiovascular diagnosis was performed by random sampling. Cox regression analysis was used to calculate hazard ratios (HRs) per one standard deviation increment of each respective log-transformed plasma biomarker with 95% confidence intervals (CI). RESULTS: Adjusted lipoprotein-associated phospholipase A2 (Lp-PLA2) activity (HR 1.33; CI 1.17-1.52) and mass (HR 1.20; CI 1.05-1.37), C-reactive protein (CRP) (HR 1.55; CI 1.36-1.76), copeptin (HR 1.46; CI 1.19-1.80), N-terminal pro-B-type natriuretic peptide (N-BNP) (HR 1.28; 1.11-1.48), and cystatin C (HR 1.19; 95% 1.10-1.29) were associated with incident symptomatic LEAD. Adjusted N-BNP (HR 1.59; CI 1.20-2.11), mid-regional proadrenomedullin (HR 1.40; CI 1.13-1.73), cystatin C (HR 1.21; CI 1.02-1.43), and CRP (HR 1.53; CI 1.13-1.73) were associated with incident symptomatic but not asymptomatic CAS. Adjusted HR was higher for Lp-PLA2 (mass) for incident isolated AAA compared to for isolated atherosclerotic disease. CONCLUSIONS: Plasma biomarker profile data support that subclinical vascular inflammation and cardiovascular stress seem to be relevant for the development of atherosclerotic disease and AAA.

One-step fabrication of dipeptide-based bifunctional polymer for individual enrichment of glycopeptides and phosphopeptides from serum.

A dipeptide-based bifunctional material immobilized with Ti4+ (denoted as APE-MBA-VPA-Ti4+) was developed using precipitation polymerization. This polymer combines hydrophilic interaction liquid chromatography (HILIC) and immobilized metal affinity chromatography (IMAC) enrichment strategies, allowing for the individual and simultaneous enrichment of glycopeptides and phosphopeptides. It demonstrated high sensitivity (0.1 fmol µL-1 for glycopeptides, 0.005 fmol µL-1 for phosphopeptides), strong selectivity (molar ratio HRP: BSA = 1:1000, ß-casein: BSA = 1:2500), consistent reusability (10 cycles) and satisfactory recovery rate (93.5 ± 1.8 % for glycopeptides, 91.6 ± 0.6 % for phosphopeptides) in the individual enrichment. Utilizing nano LC-MS/MS technology, the serum of liver cancer patients was analyzed after enrichment individually, resulting in the successful capture of 333 glycopeptides covering 262 glycosylation sites, corresponding to 131 glycoproteins, as well as 67 phosphopeptides covering 57 phosphorylation sites, related to 48 phosphoproteins. In comparison, the serum of normal healthy individuals yielded a total of 283 glycopeptides covering 244 glycosylation sites corresponding to 126 glycoproteins, as well as 66 phosphopeptides covering 56 phosphorylation sites related to 37 phosphoproteins. Label-free quantification identified 10 differentially expressed glycoproteins and 8 differentially expressed phosphoproteins in the serum of liver cancer patients. Among them, glycoproteins (HP, BCHE, AGT, C3, and PROC) and phosphoproteins (ZYX, GOLM1, GP1BB, CLU, and TNXB) showed upregulation and displayed potential as biomarkers for liver cancer.

Data Independent Acquisition Mass Spectrometry Enhanced Personalized Glycosylation Profiling of Haptoglobin in Hepatocellular Carcinoma.

Aberrant glycosylation has gained significant interest for biomarker discovery. However, low detectability, complex glycan structures, and heterogeneity present challenges in glycoprotein assay development. Using haptoglobin (Hp) as a model, we developed an integrated platform combining functionalized magnetic nanoparticles and zwitterionic hydrophilic interaction liquid chromatography (ZIC-HILIC) for highly specific glycopeptide enrichment, followed by a data-independent acquisition (DIA) strategy to establish a deep cancer-specific Hp-glycosylation profile in hepatitis B virus (HBV, n = 5) and hepatocellular carcinoma (HCC, n = 5) patients. The DIA strategy established one of the deepest Hp-glycosylation landscapes (1029 glycopeptides, 130 glycans) across serum samples, including 54 glycopeptides exclusively detected in HCC patients. Additionally, single-shot DIA searches against a DIA-based spectral library outperformed the DDA approach by 2-3-fold glycopeptide coverage across patients. Among the four N-glycan sites on Hp (N-184, N-207, N-211, N-241), the total glycan type distribution revealed significantly enhanced detection of combined fucosylated-sialylated glycans, which were the most dominant glycoforms identified in HCC patients. Quantitation analysis revealed 48 glycopeptides significantly enriched in HCC (p < 0.05), including a hybrid monosialylated triantennary glycopeptide on the N-184 site with nearly none-to-all elevation to differentiate HCC from the HBV group (HCC/HBV ratio: 2462 ± 766, p < 0.05). In summary, DIA-MS presents an unbiased and comprehensive alternative for targeted glycoproteomics to guide discovery and validation of glyco-biomarkers.

Triazine-structured covalent organic framework nanosheets with inherent hydrophilicity for the highly efficient and selective enrichment of glycosylated peptides.

Protein glycosylation plays a crucial role in various biological processes and is related to various diseases. Highly specific enrichment of glycopeptides before mass spectrometry detection is crucial for comprehensive glycoproteomic analysis. However, it still remains a great challenge due to the absence of affinity materials with excellent enrichment efficiency. In this work, a triazine structure linked by a -NH- bond of two-dimensional (2-D) covalent organic framework (COF) nanosheets was synthesized as an affinity adsorbent for the selective capture of glycopeptides. In particular, by introducing hydrophilic monomers via a bottom-up approach, the 2-D COF (denoted as NENP-1) nanosheets were provided with abundant amino groups and inherent hydrophilicity. Owing to the specific surface area and excessive accessible sites for hydrophilicity, the resulting NENP-1 nanosheets exhibited an outstanding glycopeptide enrichment efficiency from standard samples with a superior detection sensitivity (1 × 10-10 M), good enrichment selectivity (1 : 800, HRP tryptic digest to BSA protein), excellent binding capacity (100 mg g-1), great reusability, and recovery (60.2%). Furthermore, using the NENP-1 nanosheet adsorbent, twenty-four endogenous glycopeptides in the serum of patients with gastric cancer were successfully identified by LC-MS/MS technology, which illustrates a promising prospective of hydrophilic COF nanosheets in glycoproteomics research.

Association of Preoperative Copeptin Levels with Risk of All-Cause Mortality in a Prospective Cohort of Adult Cardiac Surgery Patients.

We aimed to investigate the association of preoperative copeptin, a new cardiovascular biomarker, with short- and long-term mortality in a cohort of adult patients undergoing cardiac surgery, including its potential as a prognostic marker for clinical outcome. Preoperative blood samples of the Bern Perioperative Biobank, a prospective cohort of adults undergoing cardiac surgery during 2019, were analyzed. The primary and secondary outcome measures were 30-day and 1-year all-cause mortality. Optimal copeptin thresholds were calculated with the Youden Index. Associations of copeptin levels with the two outcomes were examined with multivariable logistic regression models; their discriminatory capacity was assessed with the area under the receiver operating characteristic (AUROC). A total of 519 patients (78.4% male, median age 67 y (IQR: 60-73 y)) were included, with a median preoperative copeptin level of 7.6 pmol/L (IQR: 4.7-13.2 pmol/L). We identified an optimal threshold of 15.9 pmol/l (95%-CI: 7.7 to 46.5 pmol/L) for 30-day mortality and 15.9 pmol/L (95%-CI: 9.0 to 21.3 pmol/L) for 1-year all-cause mortality. Regression models featured an AUROC of 0.79 (95%-CI: 0.56 to 0.95) for adjusted log-transformed preoperative copeptin for 30-day mortality and an AUROC of 0.76 (95%-CI: 0.64 to 0.88) for 1-year mortality. In patients undergoing cardiac surgery, the baseline levels of copeptin emerged as a strong marker for 1-year all-cause death. Preoperative copeptin levels might possibly identify patients at risk for a complicated, long-term postoperative course, and therefore requiring a more rigorous postoperative observation and follow-up.

Anion Exchange Chromatography-Mass Spectrometry to Characterize Proteoforms of Alpha-1-Acid Glycoprotein during and after Pregnancy.

Alpha-1-acid glycoprotein (AGP) is a heterogeneous glycoprotein fulfilling key roles in many biological processes, including transport of drugs and hormones and modulation of inflammatory and immune responses. The glycoform profile of AGP is known to change depending on (patho)physiological states such as inflammatory diseases or pregnancy. Besides complexity originating from five N-glycosylation sites, the heterogeneity of the AGP further expands to genetic variants. To allow in-depth characterization of this intriguing protein, we developed a method using anion exchange chromatography (AEX) coupled to mass spectrometry (MS) revealing the presence of over 400 proteoforms differing in their glycosylation or genetic variants. More precisely, we could determine that AGP mainly consists of highly sialylated higher antennary structures with on average 16 sialic acids and 0 or 1 fucose per protein. Interestingly, a slightly higher level of fucosylation was observed for AGP1 variants compared to that of AGP2. Proteoform assignment was supported by integrating data from complementary MS-based approaches, including AEX-MS of an exoglycosidase-treated sample and glycopeptide analysis after tryptic digestion. The developed analytical method was applied to characterize AGP from plasma of women during and after pregnancy, revealing differences in glycosylation profiles, specifically in the number of antennae, HexHexNAc units, and sialic acids.

Potential role of serum copeptin among smoker T2DM patients with emphasis to ACE I/D gene polymorphism predicting DN.

Diabetic nephropathy represents one of the main long-term complications in T2DM patients. Cigarette smoking represents one of modifiable renal risk factors to kidney damage due to lead (Pb) exposure in these patients. Our goal is to investigate serum copeptin and Kidney injury molecule-1 (KIM-1) and urinary lead (UPb) in type 2 diabetes mellitus (T2DM) patients even smokers and non-smokers groups and compared to corresponding health controls and assess its associations with Angiotensin-Converting enzyme Insertion/Deletion polymorphism [ACE (I/D)] polymorphism in diabetic nephropathy progression in those patients. In present study, 106 T2DM patients and 102 healthy control individuals were enrolled. Serum glucose, copeptin, KIM-1, total cholesterol (TChol), triglycerides (TG), estimated glomerular filtration rate (eGFR) and UPb levels and ACE (I/D) polymorphisms were assessed in both groups. Results mentioned to significant variations in all parameters compared to in T2DM group compared to control group. Serum copeptin and UPb demonstrated significant difference in diabetic smokers (DS) and diabetic non-smokers (DNS) groups while KIM-1 exhibited significant change between DNS and healthy control non-smokers (CNS) groups. Positive relation was recorded between serum glucose and KIM-1 while negative one was found between serum copeptin and TChol. D allele was associated with significant variation in most parameters in T2DM, especially insertion/deletion (ID) polymorphism. ROC curve analysis (AUC) for serum copeptin was 0.8, p < 0.044 and for Kim-1 was 0.54, p = 0.13 while for uPb was 0.71, p < 0.033. Serum copeptin and UPb might be a prognostic biomarker for renal function decline in smoker T2DM patients while KIM-1 was potent marker in non-smoker T2DM with association with D allele of ACE I/D gene polymorphism.

Plasma copeptin and markers of arterial disorder in patients with type 2 diabetes, a cross-sectional study.

OBJECTIVES: There is currently limited understanding of the relationship between copeptin, the midregional portion of proadrenomedullin (MRproADM) and the midregional fragment of the N-terminal of proatrial natriuretic peptide (MRproANP), and arterial disorders. Toe brachial index (TBI) and aortic pulse wave velocity (aPWV) are established parameters for detecting arterial disorders. This study evaluated whether copeptin, MRproADM, and MRproANP were associated with TBI and aPWV in patients with type 2 diabetes with no history of cardiovascular disease (CVD). METHODS: In the CARDIPP study, a cross-sectional analysis of 519 patients with type 2 diabetes aged 55-65 years with no history of CVD at baseline, had complete data on copeptin, MRproADM, MRproANP, TBI, and aPWV was performed. Linear regression analysis was used to investigate the associations between conventional CVD risk factors, copeptin, MRproADM, MRproANP, TBI, and aPWV. RESULTS: Copeptin was associated with TBI (ß-0.0020, CI-0.0035- (-0.0005), p = 0.010) and aPWV (ß 0.023, CI 0.002-0.044, p = 0.035). These associations were independent of age, sex, diabetes duration, mean 24-hour ambulatory systolic blood pressure, glycated hemoglobin A1c, total cholesterol, estimated glomerular filtration rate, body mass index, and active smoking. CONCLUSIONS: Plasma copeptin may be a helpful surrogate for identifying individuals at higher risk for arterial disorders. TRIAL REGISTRATION:  ClinicalTrials.gov identifier NCT010497377.

Maximizing Glycoproteomics Results through an Integrated Parallel Accumulation Serial Fragmentation Workflow.

Glycoproteins play important roles in numerous physiological processes and are often implicated in disease. Analysis of site-specific protein glycobiology through glycoproteomics has evolved rapidly in recent years thanks to hardware and software innovations. Particularly, the introduction of parallel accumulation serial fragmentation (PASEF) on hybrid trapped ion mobility time-of-flight mass spectrometry instruments combined deep proteome sequencing with separation of (near-)isobaric precursor ions or converging isotope envelopes through ion mobility separation. However, the reported use of PASEF in integrated glycoproteomics workflows to comprehensively capture the glycoproteome is still limited. To this end, we developed an integrated methodology using timsTOF Pro 2 to enhance N-glycopeptide identifications in complex mixtures. We systematically optimized the ion optics tuning, collision energies, mobility isolation width, and the use of dopant-enriched nitrogen gas (DEN). Thus, we obtained a marked increase in unique glycopeptide identification rates compared to standard proteomics settings, showcasing our results on a large set of glycopeptides. With short liquid chromatography gradients of 30 min, we increased the number of unique N-glycopeptide identifications in human plasma samples from around 100 identifications under standard proteomics conditions to up to 1500 with our optimized glycoproteomics approach, highlighting the need for tailored optimizations to obtain comprehensive data.

Dynamics of serum levels and reference ranges of copeptin in the 3rd trimester of pregnancy in healthy pregnant women with uncomplicated pregnancy and delivery.

OBJECTIVE: Copeptin is a stable fragment of vasopressin. Copeptin levels have been found to reflect the degree of endothelial stress in various conditions, including acute coronary syndrome. Copeptin may be a bio marker for endothelial stress during pregnancy. However, there is still a lack of understanding of its dynamics and levels throughout pregnancy. This study aims to describe intra-individual and longitudinal changes in copeptin levels at 30th and 36th gestational weeks in healthy pregnant women with uncomplicated pregnancy and delivery and to establish specific reference ranges. METHODS: A total of 125 pregnant women with uncomplicated pregnancy and delivery were included. These women were monitored throughout their pregnancy and gave birth at the Department of Obstetrics and Gynecology Olomouc University Hospital. The blood was taken at ~30 and ~36 gestational weeks. Serum copeptin levels were measured using a Kryptor Compact PLUS analyzer. For statistics, we used R software and the "referenceRanges" package. RESULTS: It was found that serum levels of copeptin were significantly higher in the 36th week group than in the 30th week group (P < 0.05). Cook's distance was used to eliminate outliers. The 30th week median was 3.377 pmol/l, reference range = 1.343-7.829 pmol/l, and the 36 week was median 4.735 pmol/l and reference range = 2.06-13.2 pmol/l. In the 36th week reference range, the median was higher than in healthy, non-pregnant women (P < 0.05). Copeptin values can exceed 10 pmol/l, particularly after the 36th week. In the 3rd trimester, this value may indicate cardiovascular and endothelial overload. CONCLUSION: Copeptin levels were found to vary significantly depending on gestational week. The proposed reference ranges take into account the increased secretion of vasopressin in pregnancy. The existence of specific upper reference limits represents a potential advantage in detecting pregnant women prone to hypertensive disease in the 3rd trimester.

Arginine vasopressin deficiency: diagnosis, management and the relevance of oxytocin deficiency.

Polyuria-polydipsia syndrome can be caused by central diabetes insipidus, nephrogenic diabetes insipidus or primary polydipsia. To avoid confusion with diabetes mellitus, the name 'central diabetes insipidus' was changed in 2022 to arginine vasopressin (AVP) deficiency and 'nephrogenic diabetes insipidus' was renamed as AVP resistance. To differentiate the three entities, various osmotic and non-osmotic copeptin-based stimulation tests have been introduced in the past decade. The hypertonic saline test plus plasma copeptin measurement emerged as the test with highest diagnostic accuracy, replacing the water deprivation test as the gold standard in differential diagnosis of the polyuria-polydipsia syndrome. The mainstay of treatment for AVP deficiency is AVP replacement with desmopressin, a synthetic analogue of AVP specific for AVP receptor 2 (AVPR2), which usually leads to rapid improvements in polyuria and polydipsia. The main adverse effect of desmopressin is dilutional hyponatraemia, which can be reduced by regularly performing the so-called desmopressin escape method. Evidence from the past few years suggests an additional oxytocin deficiency in patients with AVP deficiency. This potential deficiency should be further evaluated in future studies, including feasible provocation tests for clinical practice and interventional trials with oxytocin substitution.

Differential expression of N-glycopeptides derived from serum glycoproteins in mild cognitive impairment (MCI) patients.

Mild cognitive impairment (MCI) is an early stage of memory loss that affects cognitive abilities with the aging of individuals, such as language or visual/spatial comprehension. MCI is considered a prodromal phase of more complicated neurodegenerative diseases such as Alzheimer's. Therefore, accurate diagnosis and better understanding of the disease prognosis will facilitate prevention of neurodegeneration. However, the existing diagnostic methods fail to provide precise and well-timed diagnoses, and the pathophysiology of MCI is not fully understood. Alterations of the serum N-glycoproteome expression could represent an essential contributor to the overall pathophysiology of neurodegenerative diseases and be used as a potential marker to assess MCI diagnosis using less invasive procedures. In this approach, we identified N-glycopeptides with different expressions between healthy and MCI patients from serum glycoproteins. Seven of the N-glycopeptides showed outstanding AUC values, among them the antithrombin-III Asn224 + 4-5-0-2 with an AUC value of 1.00 and a p value of 0.0004. According to proteomics and ingenuity pathway analysis (IPA), our data is in line with recent publications, and the glycoproteins carrying the identified N-sites play an important role in neurodegeneration.

Diagnosing and staging epithelial ovarian cancer by serum glycoproteomic profiling.

BACKGROUND: There is a need for diagnostic tests for screening, triaging and staging of epithelial ovarian cancer (EOC). Glycoproteomics of blood samples has shown promise for biomarker discovery. METHODS: We applied glycoproteomics to serum of people with EOC or benign pelvic masses and healthy controls. A total of 653 analytes were quantified and assessed in multivariable models, which were tested in an independent cohort. Additionally, we analyzed glycosylation patterns in serum markers and in tissues. RESULTS: We identified a biomarker panel that distinguished benign lesions from EOC with sensitivity and specificity of 83.5% and 90.1% in the training set, and of 86.7 and 86.7% in the test set, respectively. ROC analysis demonstrated strong performance across a range of cutoffs. Fucosylated multi-antennary glycopeptide markers were higher in late-stage than in early-stage EOC. A comparable pattern was found in late-stage EOC tissues. CONCLUSIONS: Blood glycopeptide biomarkers have the potential to distinguish benign from malignant pelvic masses, and early- from late-stage EOC. Glycosylation of circulating and tumor tissue proteins may be related. This study supports the hypothesis that blood glycoproteomic profiling can be used for EOC diagnosis and staging and it warrants further clinical evaluation.

Association of copeptin levels with patient prognosis and survival in sepsis syndromes: a meta-analysis.

BACKGROUND: Sepsis syndromes are a major burden in the ICU with very high mortality. Vasopressin and copeptin are released in response to hypovolemia and have shown potential significance in diagnosing sepsis. OBJECTIVE: To investigate the levels of copeptin in patients with sepsis syndromes and evaluate its relation with patient prognosis and mortality. METHODS: Four databases were searched for literature published from inception to the 8th of November 2022. Original research articles where copeptin was measured in sepsis patients and compared with controls were included. Data extraction and synthesis: study characteristics, levels of copeptin in the participants, and copeptin assay description were extracted. Levels of copeptin in patients were pooled and compared with controls in terms of the standard mean difference (SMD) generated using a random-effects model. RESULTS: Fifteen studies met the selection criteria. Copeptin levels were significantly higher in patients with sepsis, severe sepsis, and septic shock as compared to controls [(SMD: 1.49, 95% CI: 0.81-2.16, P<0.0001), (SMD: 1.94, 95% CI: 0.34-3.54, P=0.02), and (SMD: 2.17, 95% CI: 0.68-3.66, P=0.004), respectively]. The highest copeptin levels were noted in septic shock patients. The admission copeptin levels were significantly lower in survivors as compared to nonsurvivors (SMD: -1.73; 95% CI: -2.41 to -1.06, P<0.001). CONCLUSION AND RELEVANCE: Copeptin was significantly elevated in sepsis, severe sepsis, and septic shock. Survivors had a significantly lower copeptin during admission. Copeptin offered an excellent predictability to predict 1-month mortality. Measuring the copeptin in sepsis patients can aid treating physicians to foresee patients' prognosis.