Search Results (380)

Background: Chronic kidney disease (CKD) is a progressive global health burden often diagnosed in late stages due to reliance on invasive and centralized blood and urine tests. Saliva, as a non-invasive diagnostic fluid, has emerged as a promising alternative for assessing renal function. This scoping review aims to evaluate the diagnostic accuracy of salivary biomarkers compared to traditional methods, and to explore the potential of emerging biosensing technologies for CKD detection and monitoring. Methods: A comprehensive literature search was conducted in PubMed/MEDLINE, Scopus, Web of Science, and Cochrane Library up to 1 July 2025, following the PRISMA-ScR guidelines. Studies involving adult CKD patients and healthy controls that assessed the diagnostic performance of salivary biomarkers against validated reference standards (e.g., serum creatinine, eGFR) were included. A total of 29 eligible studies were selected after applying predefined inclusion and exclusion criteria. Results: Salivary creatinine and urea were the most frequently assessed biomarkers and demonstrated strong correlations with serum levels (AUCs up to 1.00; sensitivity and specificity frequently >85%). Several studies reported high diagnostic potential for novel salivary markers such as Trimethylamine N-oxide (TMAO), cystatin C, and amino acids. Technological innovations, including electrochemical biosensors and ATR-FTIR spectroscopy, showed promise for enhancing sensitivity and enabling point-of-care testing. However, heterogeneity in sampling protocols and limited data for early-stage CKD were notable limitations. Conclusions: Salivary diagnostics, supported by biosensor technologies, offer a feasible and non-invasive alternative for CKD screening and monitoring. Standardization, broader clinical validation, and integration into dental workflows are key to clinical implementation. Full article

Background: Serum cystatin C is a promising biomarker for vascular risk, yet its nonlinear dose–response relationships and prognostic value in general populations remain unclear, particularly for stroke-specific outcomes. Methods: This study utilized data from the National Health and Nutrition Examination Survey (NHANES) conducted in 1999–2002 cycles. A total of 11,610 participants were included in the primary analysis examining the cross-sectional association between cystatin C and stroke morbidity, using multivariate logistic regression models and odds ratios (ORs). Analyses utilized complete-case data (n = 11,610 for morbidity; n = 11,598 for mortality). Subsequently, 11,598 adults were retained for mortality endpoint analyses, which focused on the longitudinal association between cystatin C and stroke mortality, using cause-specific weighted multivariable Cox models and ratios (HRs). Restricted cubic splines identified nonlinear thresholds, and piecewise regression quantified risk gradients. Models were adjusted for sociodemographic/clinical/behavioral confounders. Results: Serum cystatin C exhibited a nonlinear dose–response relationship with stroke morbidity (p for nonlinear < 0.001), with an inflection point at 1.24 mg/L; below this threshold, each 0.1 mg/L increase conferred 13.84-fold higher odds (95% CI: 7.11–27.03, p < 0.001). For mortality, nonlinear thresholds were identified at 1.24 mg/L for all-cause/cause-specific mortality (HR = 6.73–10.60 per 0.1 mg/L increase, p < 0.001) and 1.81 mg/L for stroke-specific mortality. Conversely, cerebrovascular mortality demonstrated a linear association (HR = 1.43 per 1 mg/L increase, p = 0.008), though cystatin C independently predicted risk (HR = 1.38/continuous, p = 0.034 in fully adjusted models). Conclusions: This study identifies serum cystatin C as an independent predictor after full adjustment of stroke morbidity and all-cause and cardio-cerebrovascular mortality. Consequently, cystatin C emerges as a dual-purpose biomarker for early vascular injury detection in subclinical populations and integrated mortality risk stratification. Future research should validate these thresholds in prospective neuroimaging-confirmed cohorts and investigate interventions targeting cystatin C pathways to optimize preventive strategies. Full article

Cathepsins, a family of lysosomal proteases, play critical roles in maintaining cellular homeostasis through protein degradation and modulation of immune responses. In the central nervous system (CNS), their functions extend beyond classical proteolysis, influencing neuroinflammation, synaptic remodeling, and neurodegeneration. Emerging evidence underscores the crucial role of microglial cathepsins in the pathophysiology of several neurological disorders. This review synthesizes current knowledge on the involvement of cathepsins in a spectrum of CNS diseases, including Parkinson’s disease, Alzheimer’s disease, multiple sclerosis, amyotrophic lateral sclerosis, epilepsy, Huntington’s disease, and ischemic stroke. We highlight how specific cathepsins contribute to disease progression by modulating key pathological processes such as α-synuclein and amyloid-β clearance, tau degradation, lysosomal dysfunction, neuroinflammation, and demyelination. Notably, several cathepsins demonstrate both neuroprotective and pathogenic roles depending on disease context and expression levels. Additionally, the balance between cathepsins and their endogenous inhibitors, such as cystatins, emerges as a critical factor in CNS pathology. While cathepsins represent promising biomarkers and therapeutic targets, significant gaps remain in our understanding of their mechanistic roles across diseases. Future studies focusing on their regulation, substrate specificity, and interplay with genetic and epigenetic factors may yield novel strategies for early diagnosis and disease-modifying treatments in neurology. Full article

Recurrent aphthous stomatitis (RAS) is the most common ulcerative disorder of the oral cavity, although its etiology is still unknown. The present study aimed to identify the proteomic profile associated with the RAS inflammatory process, thereby enhancing our understanding of its etiopathogenesis. We compared salivary protein profiles of RAS patients during an active episode of oral ulceration (30 patients, mean age 36.9) to those from healthy donors without a history of RAS (30 healthy subjects, mean age 37.9). Using 2D-electrophoresis and mass spectrometry (MALDI-TOF) analysis, we identified 17 proteins that were differentially expressed in the two groups. Notably, Cystatin SN (CST1) appeared to be significantly downregulated in RAS patients. These findings were validated by Western blot analysis: CST1 was detected in only 3 of the 30 RAS cases, while it was strongly expressed in all the healthy subjects. Although preliminary, our results suggest a potential role for CST1 in the etiopathogenesis of RAS. Interestingly, the relative absence of CST1 in RAS patients seems to align with some clinical and molecular features of this disease. Full article

Aim: To assess oxidative–inflammatory biomarker prediction of incident CKD after 1-year follow-up in a population with overweight/obesity and metabolic syndrome. Methods: Prospective nested case–control study comprising 117 CKD incident cases and 117 matched controls free of CKD after 1-year follow-up conducted in 55–75-year-old participants. Controls were time-matched 1:1 to cases by intervention group, age (≤65 vs. >65 years), and sex. Serum creatinine (SCr), cystatin C (CyC), and urine albumin-to-creatinine ratio (UACR) were measured at baseline, and CKD Epidemiology Collaboration equations for Caucasians were used to assess SCr, CyC, and CyC-SCr-based estimated Glomerular Filtration Rate (eGFR). Baseline levels of malondialdehyde (MDA), carbonyls, tumour necrosis factor alpha (TNFα), interleukin (IL)-1β, IL-1ra, IL-6, monocyte chemoattractant protein 1 (MCP-1), and leptin were determined from fasting serum samples. An inflammatory-oxidative stress score based on these biomarkers was calculated. Incident CKD was defined by eGFR-SCr <60 mL/min/1.73 m², and/or UACR ≥30 mg/g in the absence of CKD at baseline. Results: UACR positively correlated with pro-inflammatory markers (IL-1β; TNFα) and oxidative damage marker (MDA); eGFR-cyC showed negative correlations with IL-1β and IL-1ra, and eGFR-SCr with leptin. The odds ratios (OR; 95% CI) for incident CKD in the highest vs. the lowest tertile of IL-1ra IL-6 and TNFα were (2.22; 1.22–4.04), (7.03; 2.88–17.14), and (3.79; 1.79–8.02), respectively. The inflammatory–oxidative stress score was associated with incident CKD (OR per 1-SD increment: 2.06; 1.49–2.83). Conclusions: Inflammatory/oxidative stress is associated with CKD incidence in individuals with high cardiovascular risk, underscoring the importance in identify early inflammation to prevent this disease. Full article

Acute kidney injury (AKI) is a serious clinical condition that is linked to markedly higher rates of morbidity and mortality in cirrhosis patients. Its diagnosis is challenging due to overlapping clinical and laboratory features among causes such as hepatorenal syndrome (HRS), acute tubular injury (ATI), and prerenal hypovolemia. In order to address the distinct pathophysiology and clinical context of cirrhosis, the definitions and classification of AKI have changed over time, moving from RIFLE and AKIN to KDIGO and ICA-AKI. Because cirrhosis patients have altered muscle mass and fluid retention, traditional markers like serum creatinine (sCr) and urine output have significant limitations. Neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), interleukin-18 (IL-18), and cystatin C (CysC) are some of the new biomarkers that have shown promise in early AKI detection and in differentiating structural from functional kidney injury. NGAL and KIM-1 are sensitive indicators of tubular damage with potential prognostic implications. IL-18 reflects inflammatory injury, and CysC offers a more reliable measure of glomerular filtration. Incorporating these markers may improve early diagnosis, risk stratification, and treatment decisions, representing a key direction for future research in managing AKI in cirrhosis. Full article

Background and Objectives: This study aimed to explore the risk factors of histopathological crescent formation in pediatric IgA vasculitis nephritis (IgAVN). Materials and Methods: Enrolled patients with biopsy-proven IgAVN from Zhejiang University’s hospital were split into two groups: 377 with no crescents on histopathology (Group 1) and 364 with crescentic nephritis (Group 2). Collected data included clinical features, lab indicators, histopathological grading, and factors causing glomerular sclerosis. Logistic regression was used to assess factors affecting crescent formation in IgAVN. Double-immunofluorescence assay was used to detect TGF-β1, MCP-1, α-SMA, Collagen I, and FN1 in kidney biopsy specimens. The relationship between kidney fibrosis factors and histopathological grade were analyzed using Chi-square and Pearson tests. Results: A total of 741 patients with IgAVN were included in the study. Univariate logistic regression identified potential factors related to crescent formation, including age, gender, clinical classification, hematuria grade, 24 h urine protein level, peripheral white blood cells (WBCs), serum albumin, Cystatin-C, APTT, and PT. Multivariate analysis revealed statistical significance for age, 24 h urine protein, and WBCs across pathological grades (p < 0.05). Mantel–Haenszel Chi-square tests indicated a linear relationship between IgAVN pathological grade and α-SMA, TGF-β1, MCP-1, and FN1. Pearson correlation analysis confirmed a positive correlation between pathological grade and these markers. Conclusions: Age, 24 h urinary protein, and blood WBCs are identified as risk factors for histopathological crescent formation in children with IgAVN. Additionally, a higher pathological grade is associated with more pronounced fibrosis indicators. Full article

Background and Objectives: The long-term renal and cardiovascular effects of neonatal acute kidney injury (AKI) in preterm infants remain unclear. This study investigated whether neonatal AKI leads to persistent subclinical kidney injury and blood pressure changes in school-aged children born preterm. Methods: In this prospective cohort, preterm-born children (≤35 weeks’ gestation) with (n = 19) and without (n = 38) neonatal AKI were evaluated at 7–12 years. A term-born control group (n = 44) was included for biomarker comparison. Assessments included perinatal data, anthropometry, office and ambulatory blood pressure monitoring (ABPM), and renal ultrasonography. Kidney function was evaluated using serum creatinine (sCr), cystatin C, and estimated glomerular filtration rate (eGFR). Tubular injury was assessed using urinary kidney injury molecule-1/Cr (KIM-1/Cr), neutrophil gelatinase-associated lipocalin/Cr (NGAL/Cr), and trefoil factor 3/Cr (TFF3/Cr) ratios, as well as serum TFF3. Results: Conventional kidney function markers were similar among groups. However, the AKI group had higher serum cystatin C, lower cystatin C–based eGFR, and elevated urinary KIM-1/Cr and NGAL/Cr compared to no-AKI and term controls. Serum TFF3 was also higher in the AKI group. ABPM revealed higher nocturnal systolic blood pressure and blood pressure load in the AKI group. Kidney size did not differ between preterm subgroups. Conclusions: Neonatal AKI in preterm infants is associated with subtle alterations and potential renal stress or injury at school age, detectable only with sensitive biomarkers and ABPM. Further prospective studies are needed to validate these biomarkers and determine their role in predicting long-term outcomes in preterm infants with neonatal AKI. Full article

Background: This study presents an innovative approach to cardiovascular disease (CVD) risk prediction based on a comprehensive analysis of clinical, immunological and biochemical markers using mathematical modelling and machine learning methods. Baseline data include indices of humoral and cellular immunity (CD59, CD16, IL-10, CD14, CD19, CD8, CD4, etc.), cytokines and markers of cardiovascular disease, inflammatory markers (TNF, GM-CSF, CRP), growth and angiogenesis factors (VEGF, PGF), proteins involved in apoptosis and cytotoxicity (perforin, CD95), as well as indices of liver function, kidney function, oxidative stress and heart failure (albumin, cystatin C, N-terminal pro B-type natriuretic peptide (NT-proBNP), superoxide dismutase (SOD), C-reactive protein (CRP), cholinesterase (ChE), cholesterol, and glomerular filtration rate (GFR)). Clinical and behavioural risk factors were also considered: arterial hypertension (AH), previous myocardial infarction (PICS), aortocoronary bypass surgery (CABG) and/or stenting, coronary heart disease (CHD), atrial fibrillation (AF), atrioventricular block (AB block), and diabetes mellitus (DM), as well as lifestyle (smoking, alcohol consumption, physical activity level), education, and body mass index (BMI). Methods: The study included 52 patients aged 65 years and older. Based on the clinical, biochemical and immunological data obtained, a model for predicting the risk of premature cardiovascular aging was developed using mathematical modelling and machine learning methods. The aim of the study was to develop a predictive model allowing for the early detection of predisposition to the development of CVDs and their complications. Numerical methods of mathematical modelling, including Runge–Kutta, Adams–Bashforth and backward-directed Euler methods, were used to solve the prediction problem, which made it possible to describe the dynamics of changes in biomarkers and patients’ condition over time with high accuracy. Results: HLA-DR (50%), CD14 (41%) and CD16 (38%) showed the highest association with aging processes. BMI was correlated with placental growth factor (37%). The glomerular filtration rate was positively associated with physical activity (47%), whereas SOD activity was negatively correlated with it (48%), reflecting a decline in antioxidant defence. Conclusions: The obtained results allow for improving the accuracy of cardiovascular risk prediction, and form personalised recommendations for the prevention and correction of its development. Full article

Sepsis-associated acute kidney injury (S-AKI) represents a significant health problem associated with adverse outcomes. Our study aimed to assess the value of serum cystatin-C (sCysC) and TNF-α (rs361525) in combination for diagnosing S-AKI patients and predicting their adverse outcomes. The study included 100 critically ill neonates and 100 controls. Patients were categorized into an S-AKI group and a non-AKI group. TNF-α (−238, rs361525) genotyping was performed using RT-PCR, and sCysC was assessed using ELISA. Our study showed a fundamental difference in the genotype frequencies of TNF-α (−238, rs361525) and SNP between S-AKI and non-AKI patients. Furthermore, there was a significant relationship between cystatin C and TNF-α (−238, rs361525), where cystatin C was higher in patients with AA alleles than in patients with GA and GG alleles. Combining GA + AA genotypes with elevated serum cystatin-C levels can serve as a potential diagnostic and prognostic biomarker for AKI development in this population. The GA/AA genotypes independently predicted S-AKI risk (OR = 6.64, p < 0.001). At the same time, elevated sCysC (>9.4 mg/L) emerged as a sensitive biomarker (AUC = 0.848) and independent predictor of adverse outcomes. Collectively, these findings contribute to the growing field of personalized medicine and represent a strategic advantage, enabling prevention-focused care rather than the treatment of established disease. Full article

Chronic kidney disease (CKD) is associated with heart failure and neurological disorders. Therefore, point-of-care (POC) detection of CKD is essential, allowing disease monitoring from home and alleviating healthcare professionals’ workload. Lateral flow immunoassays (LFIAs) facilitate POC testing for a renal function biomarker, serum Cystatin C (CysC). LF devices were fabricated and optimised by varying the diluted sample volume, the nitrocellulose (NC) membrane, bed volume, AuNPs’ OD value and volume, and assay formats of partial or full LF systems. Notably, 310 samples were analysed to satisfy the minimum sample size for statistical calculations. This allowed for a comparison between the LFIAs’ results and the general Roche standard assay results from the Southern Health and Social Care Trust. Bland–Altman plots indicated the LFIAs measured 0.51 mg/L lower than the Roche assays. With the 95% confidence interval, the Roche method might be 0.24 mg/L below the LFIAs’ results or 1.27 mg/L above the LFIAs’ results. In summary, the developed non-fluorescent LFIAs could detect clinical CysC values in agreement with Roche assays. Even though the developed LFIA had an increased bias in low CysC concentration (below 2 mg/L) detection, the developed LFIA can still alert patients at the early stages of renal function impairment. Full article

Blood bacterial DNA (BB-DNA) has been identified as a novel biomarker for metabolic dysfunction, yet its relationship with epigenetic features in type 2 diabetes mellitus (DM2) patients remains largely unexplored. This study investigated the relationship between BB-DNA and epigenetic, inflammatory, and aging-related markers in 285 elderly both with and without DM2. BB-DNA levels were higher in DM2 patients than in non-diabetic subjects, with the highest levels in those with severe renal impairment. BB-DNA showed a positive association with plasma IL-1β, linking bacterial DNA to systemic inflammation. Epigenetic analysis revealed a negative correlation between BB-DNA and DNA methylation-based leukocyte telomere length, suggesting accelerated aging in DM2. Additionally, BB-DNA was positively associated with DNAm-based biological age estimators, particularly DNAmPhenoAge and DNAmAge Skin Blood Clock. BB-DNA also correlated with DNAmVEGFA and DNAmCystatin C, key markers of diabetic nephropathy and vascular dysfunction. Furthermore, BB-DNA levels were associated with hypomethylation of genes involved in inflammation (e.g., IL1β, TNFα, IFNγ), cellular senescence (p16, p21, TP53), and metabolic regulation (e.g., IGF1, SREBF1, ABCG1, PDK4). These associations suggest that increased BB-DNA may reflect and potentially promote a pro-inflammatory and pro-senescent epigenetic profile in DM2. Importantly, many of these associations remained significant after adjusting for diabetes status, supporting BB-DNA as a robust biomarker across clinical subgroups. These findings provide new insights into the relationship between BB-DNA, inflammation, and epigenetic aging in DM2, highlighting BB-DNA as a potential biomarker for disease progression and complications, particularly in relation to renal dysfunction and systemic inflammation. Full article

Background: Type 2 diabetes mellitus (T2DM) is an epidemic chronic disease that affects millions of people worldwide. This study aims to explore the impact of T2DM on the tear proteome, specifically investigating whether alterations occur before the development of diabetic retinopathy. Methods: Flush tear samples were collected from healthy subjects and subjects with preDM and T2DM. Tear proteins were processed and analyzed by mass spectrometry-based shotgun proteomics using a data-independent acquisition parallel acquisition serial fragmentation (diaPASEF) approach. Machine learning algorithms, including random forest, lasso regression, and support vector machine, and statistical tools were used to identify potential biomarkers. Results: Machine learning models identified 17 proteins with high importance in classification. Among these, five proteins (cystatin-S, S100-A11, submaxillary gland androgen-regulated protein 3B, immunoglobulin lambda variable 3–25, and lambda constant 3) exhibited differential abundance across these three groups. No correlations were identified between proteins and clinical assessments of the ocular surface. Notably, the 17 important proteins showed superior prediction accuracy in distinguishing all three groups (healthy, preDM, and T2DM) compared to the five proteins that were statistically significant. Conclusions: Alterations in the tear proteome profile were observed in adults with preDM and T2DM before the clinical diagnosis of ocular abnormality, including retinopathy. Full article

Exercise training in extreme temperatures concurrent with hypohydration status may potentiate the development of acute kidney injury (AKI) in young, healthy persons. Background/Objectives: It is unknown how repeated training bouts in ambient higher temperatures and humidity may influence measures of AKI. The purpose of this study was to investigate hydration status and renal biomarkers related to AKI in NCAA Division I female soccer athletes during preseason conditioning. Methods: A convenience sample of n = 21 athletes were recruited (mean ± SEM; age: 19.3 ± 0.25 y; height: 169.6 ± 1.36 cm; mass: 68.43 ± 2.46 kg; lean body mass: 45.91 ± 1.13 kg; fat mass: 22.51 ± 1.69 kg; body fat %: 32.22 ± 1.32%). The average temperature was 27.43 ± 0.19 °C, and the humidity was 71.69 ± 1.82%. Body composition, anthropometric, workload, and 14 urine samples were collected throughout the preseason training period for urine specific gravity (USG), creatinine (uCr), cystatin C (uCyst-C), and neutrophil gelatinase-associated lipocalin (uNGAL) analyses. Results: Our investigation showed that, when compared to baseline (D0), the athletes maintained a USG-average euhydrated status (1.019 ± 0.001) and were euhydrated prior to each exhibition game (D5-Pre: p = 0.03; 1.011 ± 0.001; D10-Pre: p = 0.0009; 1.009 ± 0.001); uCr was elevated on D8 (p = 0.001; 6.29 ± 0.44 mg·dL⁻¹·LBM⁻¹) and D10-Post (p = 0.02; 6.61 ± 0.44 mg·dL⁻¹·LBM⁻¹); uCyst-C was elevated on D6 through D10 (p = 0.001; ~0.42 ± 0.01 mg·dL⁻¹); no differences were found in uNGAL concentration. The highest distance (m) displaced was found during exhibition games (D5: p = <0.0001; ~8.6 km and D10: p = <0.0001; ~9.6 km). During the preseason conditioning, the athletes maintained a euhydrated status (~1.019) via USG, an increase in uCr that averaged within a normal range (208 mg·dL⁻¹), and an increase in uCyst-C to near AKI threshold levels (0.42 mg·L⁻¹) for several practice sessions, followed by an adaptive decline. No differences were found in uNGAL, which may be explained by athlete variation, chosen time sample collection, and variation in training and hydration status. Conclusions: The athletes maintained a euhydrated status, and this may help explain why urinary markers did not change or meet the reference threshold for AKI. Full article

About a quarter of COVID-19 patients develop acute kidney injury (AKI), worsening prognosis and increasing mortality. Severe COVID-19 often triggers a hyperactive immune response, influencing disease outcomes. This study examined the correlation between kidney injury biomarkers, inflammatory mediators, and mortality in COVID-19 patients. Blood samples from 390 COVID-19 patients were collected at admission and before the outcome. Serum Cystatin C (CysC), albumin, and plasma NGAL were measured via nephelometry, while inflammatory mediators (IL-4, IL-6, IL-10, IL-15, IFN-γ, TNF-α, and IL-1β) were assessed by ELISA. Most patients were male, with hypertension and diabetes as common comorbidities, and a high ICU admission rate. Lower albumin and elevated CysC and NGAL were linked to mortality. Increased inflammatory mediators correlated with lower albumin and higher CysC and NGAL, reinforcing the connection between systemic inflammation and kidney dysfunction. Elevated cytokines and kidney injury biomarkers, including NGAL, CysC, and low albumin, are strongly associated with higher mortality in COVID-19 patients. These findings highlight the role of inflammation and kidney function markers in identifying high-risk individuals, improving patient management, and mitigating complications. Monitoring these biomarkers remains crucial for managing long-term health impacts and future outbreaks Full article