Serum and urinary biomarkers of vancomycin-induced acute kidney injury: A prospective, observational analysis.

Vancomycin, a first-line drug for treating methicillin-resistant Staphylococcus aureus infections, is associated with acute kidney injury (AKI). This study involved an evaluation of biomarkers for AKI detection and their comparison with traditional serum creatinine (SCr). We prospectively enrolled patients scheduled to receive intravenous vancomycin for methicillin-resistant S aureus infection. Blood samples for pharmacokinetic assessment and SCr and cystatin C (CysC) measurements were collected at baseline and on days 3, 7, and 10 from the initiation of vancomycin administration (day 1). Urinary biomarkers, including kidney injury molecule 1 (KIM-1), neutrophil gelatinase-associated lipocalin, and clusterin, were collected from days 1 to 7 and adjusted for urinary creatinine levels. The estimated glomerular filtration rate (eGFR) was calculated using the Chronic Kidney Disease Epidemiology Collaboration equation. Of the 42 patients, 6 experienced vancomycin-induced AKI. On day 7, the change from baseline eGFR using CysC (ΔeGFRCysC) showed a stronger correlation with vancomycin area under the curve (r = -0.634, P < .001) than that using SCr (ΔeGFRSCr; r = -0.437, P = .020). ΔeGFRSCr showed no significant correlation with vancomycin pharmacokinetic in patients with body mass index ≥23. The median (interquartile range) level of KIM-1 (µg/mg) was significantly higher in the AKI group (0.006 [0.005-0.008]) than in the non-AKI group (0.004 [0.001-0.005]) (P = .039, Mann-Whitney U test), with area under the receiver operating characteristic curve (95% confidence interval) of 0.788 (0.587-0.990). Serum CysC, particularly in overweight individuals or those with obesity, along with urinary KIM-1 are important predictors of vancomycin-induced AKI. These results may aid in selecting better biomarkers than traditional SCr for detecting vancomycin-induced AKI.

Unraveling the molecular complexity: Wtap/Ythdf1 and Lcn2 in novel traumatic brain injury secondary injury mechanisms.

The primary aim of this research was to explore the functions of Wtap and Ythdf1 in regulating neuronal Lipocalin-2 (Lcn2) through m6A modification in traumatic brain injury (TBI). By employing transcriptome sequencing and enrichment analysis, we identified the Wtap/Ythdf1-mediated Lcn2 m6A modification pathway as crucial in TBI. In our in vitro experiments using primary cortical neurons, knockout of Wtap and Ythdf1 led to the inhibition of Lcn2 m6A modification, resulting in reduced neuronal death and inflammation. Furthermore, overexpression of Lcn2 in cortical neurons induced the activation of reactive astrocytes and M1-like microglial cells, causing neuronal apoptosis. In vivo experiments confirmed the activation of reactive astrocytes and microglial cells in TBI and importantly demonstrated that Wtap knockdown improved neuroinflammation and functional impairment. These findings underscore the significance of Wtap/Ythdf1-mediated Lcn2 regulation in TBI secondary injury and suggest potential therapeutic implications for combating TBI-induced neuroinflammation and neuronal damage.

Mesenchymal Stem Cells Alleviate Mouse Sepsis-Induced Cardiomyopathy by Inhibiting the NR1D2/LCN2 Pathway.

ABSTRACT: Sepsis is characterized as a systemic inflammatory response syndrome resulting from infection, leading to the development of multiple organ dysfunction syndrome. Sepsis-induced cardiomyopathy (SICM) is a frequently encountered condition in clinical settings. Mesenchymal stem cells (MSCs) possess inherent immunomodulatory and anti-inflammatory attributes, rendering them a promising therapeutic approach to reestablish the equilibrium between anti-inflammatory and proinflammatory systems in septic patients. Consequently, MSCs are frequently employed in clinical investigations. In this study, the author established a mouse SICM model through cecal ligation and puncture and administered MSCs through the tail vein. Following successful modeling, the myocardial function and histopathological changes were detected by echocardiography, hematoxylin-eosin staining, terminal deoxynucleotidyl transferase dUTP nick end labeling staining, enzyme-linked immunosorbent assay,, and other experiments. As a result, MSCs demonstrated the ability to enhance myocardial function, promote cardiac tissue repair, suppress inflammatory response, reduce levels of myocardial injury markers, and mitigate oxidative stress. In addition, transcriptome and proteome analyses were conducted. Through differential expression analysis, functional enrichment analysis, and multiomics association analysis, it was revealed that the transcriptional factors nuclear receptor subfamily 1 (NR1D2) and target gene lipocalin 2 (LCN2) played key roles in mediating the effects of MSCs on SICM. JASPAR website and ChIP-qPCR experiment were used to predict and confirm the targeting relationship between them. Subsequent cell coculture experiments and a series of experiments confirmed that MSCs attenuated cardiomyocyte injury by downregulating the expression of NR1D2 and its downstream target gene LCN2. In conclusion, MSCs alleviate mice SICM through inhibiting NR1D2/LCN2 pathway.

IL-17 Mildly Rescued the Impaired Proliferation of Alveolar Epithelial Cells Induced by LCN2 Overexpression.

Introduction: The impaired proliferative capacity of alveolar epithelial cells after injury is an important factor causing epithelial repair dysfunction, leading to the occurrence of idiopathic pulmonary fibrosis (IPF). Alveolar type 2 (AT2) cells as the stem cells of alveolar epithelium participate in the repair process after alveolar injury. Lipocalin-2 (LCN2) participates in multiple processes regulating the pathological process of alveolar epithelial cells, but the mechanisms involved are still unclear. Method: We used a BLM-treated mouse model to characterize the expression of LCN2 in lung fibrosis regions and analyzed the location of LCN2 in alveolar epithelial cells. Moreover, human pulmonary alveolar epithelial cells (HPAEpiCs) were transfected with the LCN2 overexpression plasmid vector in vitro. Recombinant human interleukin-17 (IL-17) protein (rhIL-17) at different concentrations was administered to intervene in HPAEpiCs, observing cell viability and analyzing the concentration-dependent effect of IL-17. Results: LCN2 was increased in the alveolar epithelium post-BLM injury, and highly expressed LCN2 was mainly concentrated on AT2 cells in BLM-injured lungs. Meanwhile, LCN2-overexpressing HPAEpiCs showed impaired cell viability and cell growth. HPAEpiC intervention with rhIL-17 mildly rescued the impaired cell proliferation induced by LCN2 overexpression, and the effect of IL-17 intervention was partially concentration-dependent. Conclusions: The results revealed the reversed effect of IL-17 on the impaired proliferative capacity of the alveolar epithelium induced by LCN2 overexpression. The target alveolar epithelial cells regulated by this process were AT2 cells, providing new clues for alveolar epithelium repair after injury and the treatment of lung injury diseases.

Identification and multimodal characterization of a specialized epithelial cell type associated with Crohn's disease.

Crohn's disease (CD) is a complex chronic inflammatory disorder with both gastrointestinal and extra-intestinal manifestations associated immune dysregulation. Analyzing 202,359 cells from 170 specimens across 83 patients, we identify a distinct epithelial cell type in both terminal ileum and ascending colon (hereon as 'LND') with high expression of LCN2, NOS2, and DUOX2 and genes related to antimicrobial response and immunoregulation. LND cells, confirmed by in-situ RNA and protein imaging, are rare in non-IBD controls but expand in active CD, and actively interact with immune cells and specifically express IBD/CD susceptibility genes, suggesting a possible function in CD immunopathogenesis. Furthermore, we discover early and late LND subpopulations with different origins and developmental potential. A higher ratio of late-to-early LND cells correlates with better response to anti-TNF treatment. Our findings thus suggest a potential pathogenic role for LND cells in both Crohn's ileitis and colitis.

Acyl-CoA binding protein for the experimental treatment of anorexia.

Extracellular acyl-coenzyme A binding protein [ACBP encoded by diazepam binding inhibitor (DBI)] is a phylogenetically ancient appetite stimulator that is secreted in a nonconventional, autophagy-dependent fashion. Here, we show that low ACBP/DBI plasma concentrations are associated with poor prognosis in patients with anorexia nervosa, a frequent and often intractable eating disorder. In mice, anorexia induced by chronic restraint stress (CRS) is accompanied by a reduction in circulating ACBP/DBI concentrations. We engineered a chemical-genetic system for the secretion of ACBP/DBI through a biotin-activatable, autophagy-independent pathway. In transgenic mice expressing this system in hepatocytes, biotin-induced elevations in plasma ACBP/DBI concentrations prevented anorexia induced by CRS or chemotherapeutic agents including cisplatin, doxorubicin, and paclitaxel. ACBP/DBI reversed the CRS or cisplatin-induced increase in plasma lipocalin-2 concentrations and the hypothalamic activation of anorexigenic melanocortin 4 receptors, for which lipocalin-2 is an agonist. Daily intravenous injections of recombinant ACBP/DBI protein or subcutaneous implantation of osmotic pumps releasing recombinant ACBP/DBI mimicked the orexigenic effects of the chemical-genetic system. In conclusion, the supplementation of extracellular and peripheral ACBP/DBI might constitute a viable strategy for treating anorexia.

Repetitive Administration of Low-Dose Lipopolysaccharide Improves Repeated Social Defeat Stress-Induced Behavioral Abnormalities and Aberrant Immune Response.

Repetitive exposure of innate immune cells to a subthreshold dosage of endotoxin components may modulate inflammatory responses. However, the regulatory mechanisms in the interactions between the central nervous system (CNS) and the immune system remain unclear. This study aimed to investigate the effects of lipopolysaccharide (LPS) preconditioning in repeated social defeat stress (RSDS)-induced abnormal immune responses and behavioral impairments. This study aimed to elucidate the mechanisms that underlie the protective effects of repeated administration of a subthreshold dose LPS on behavioral impairments using the RSDS paradigm. LPS preconditioning improved abnormal behaviors in RSDS-defeated mice, accompanied by decreased monoamine oxidases and increased glucocorticoid receptor expression in the hippocampus. In addition, pre-treated with LPS significantly decreased the recruited peripheral myeloid cells (CD11b+CD45hi), mainly circulating inflammatory monocytes (CD11b+CD45hiLy6ChiCCR2+) into the brain in response to RSDS challenge. Importantly, we found that LPS preconditioning exerts its protective properties by regulating lipocalin-2 (LCN2) expression in microglia, which subsequently induces expressions of chemokine CCL2 and pro-inflammatory cytokine. Subsequently, LPS-preconditioning lessened the resident microglia population (CD11b+CD45intCCL2+) in the brains of the RSDS-defeated mice. Moreover, RSDS-associated expressions of leukocytes (CD11b+CD45+CCR2+) and neutrophils (CD11b+CD45+Ly6G+) in the bone marrow, spleen, and blood were also attenuated by LPS-preconditioning. In particular, LPS preconditioning also promoted the expression of endogenous antioxidants and anti-inflammatory proteins in the hippocampus. Our results demonstrate that LPS preconditioning ameliorates lipocalin 2-associated microglial activation and aberrant immune response and promotes the expression of endogenous antioxidants and anti-inflammatory protein, thereby maintaining the homeostasis of pro-inflammation/anti-inflammation in both the brain and immune system, ultimately protecting the mice from RSDS-induced aberrant immune response and behavioral changes.

Upconverting Nanoparticle-based Enhanced Luminescence Lateral-Flow Assay for Urinary Biomarker Monitoring.

Development of efficient portable sensors for accurately detecting biomarkers is crucial for early disease diagnosis, yet remains a significant challenge. To address this need, we introduce the enhanced luminescence lateral-flow assay, which leverages highly luminescent upconverting nanoparticles (UCNPs) alongside a portable reader and a smartphone app. The sensor's efficiency and versatility were shown for kidney health monitoring as a proof of concept. We engineered Er3+- and Tm3+-doped UCNPs coated with multiple layers, including an undoped inert matrix shell, a mesoporous silica shell, and an outer layer of gold (UCNP@mSiO2@Au). These coatings synergistically enhance emission by over 40-fold and facilitate biomolecule conjugation, rendering UCNP@mSiO2@Au easy to use and suitable for a broad range of bioapplications. Employing these optimized nanoparticles in lateral-flow assays, we successfully detected two acute kidney injury-related biomarkers─kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL)─in urine samples. Using our sensor platform, KIM-1 and NGAL can be accurately detected and quantified within the range of 0.1 to 20 ng/mL, boasting impressively low limits of detection at 0.28 and 0.23 ng/mL, respectively. Validating our approach, we analyzed clinical urine samples, achieving biomarker concentrations that closely correlated with results obtained via ELISA. Importantly, our system enables biomarker quantification in less than 15 min, underscoring the performance of our novel UCNP-based approach and its potential as reliable, rapid, and user-friendly diagnostics.

Posidonia oceanica (L.) Delile Is a Promising Marine Source Able to Alleviate Imiquimod-Induced Psoriatic Skin Inflammation.

Psoriasis is a chronic immune-mediated inflammatory cutaneous disease characterized by elevated levels of inflammatory cytokines and adipokine Lipocalin-2 (LCN-2). Recently, natural plant-based products have been studied as new antipsoriatic compounds. We investigate the ability of a leaf extract of the marine plant Posidonia oceanica (POE) to inhibit psoriatic dermatitis in C57BL/6 mice treated with Imiquimod (IMQ). One group of mice was topically treated with IMQ (IMQ mice) for 5 days, and a second group received POE orally before each topical IMQ treatment (IMQ-POE mice). Psoriasis Area Severity Index (PASI) score, thickness, and temperature of the skin area treated with IMQ were measured in both groups. Upon sacrifice, the organs were weighed, and skin biopsies and blood samples were collected. Plasma and lesional skin protein expression of IL-17, IL-23, IFN-γ, IL-2, and TNF-α and plasma LCN-2 concentration were evaluated by ELISA. PASI score, thickness, and temperature of lesional skin were reduced in IMQ-POE mice, as were histological features of psoriatic dermatitis and expression of inflammatory cytokines and LCN-2 levels. This preliminary study aims to propose P. oceanica as a promising naturopathic anti-inflammatory treatment that could be introduced in Complementary Medicine for psoriasis.

Associations between Microglia and Astrocytic Proteins and Tau Biomarkers across the Continuum of Alzheimer's Disease.

Recent investigations implicate neuroinflammatory changes, including astrocyte and microglia activation, as crucial in the progression of Alzheimer's disease (AD) Thus, we compared selected proteins reflecting neuroinflammatory processes to establish their connection to AD pathologies. Our study, encompassing 80 subjects with (n = 42) AD, (n = 18) mild cognitive impairment (MCI) and (n = 20) non-demented controls compares the clinical potential of tested molecules. Using antibody-based methods, we assessed concentrations of NGAL, CXCL-11, sTREM1, and sTREM2 in cerebrospinal fluid (CSF). Proinflammatory proteins, NGAL, and CXCL-11 reached a peak in the early stage of the disease and allowed for the identification of patients with MCI. Furthermore, the concentration of the anti-inflammatory molecule sTREM2 was highest in the more advanced stage of the disease and permitted differentiation between AD and non-demented controls. Additionally, sTREM2 was biochemically linked to tau and pTau in the AD group. Notably, NGAL demonstrated superior diagnostic performance compared to classical AD biomarkers in discriminating MCI patients from controls. These findings suggest that proteins secreted mainly through microglia dysfunction might play not only a detrimental but also a protective role in the development of AD pathology.

Mechanistic insights into Lipocalin-2 in ischemic stroke and hemorrhagic brain injury: Integrating animal and clinical studies.

Brain injuries, including strokes and traumatic brain injuries (TBI), are a major global health concern, contributing significantly to both mortality and long-term disability. Recent research has identified lipocalin-2 (LCN2), a glycoprotein secreted by various brain cells, as a key factor in influencing brain injury outcomes. Evidence from animal and clinical studies firmly establishes the pivotal role of LCN2 in driving the inflammatory responses triggered by damage to brain tissue. Furthermore, increased LCN2 promotes cellular differentiation, blood-brain barrier breakdown, and decreases cell viability. Interventions with LCN2 inhibitors attenuated brain injury through a reduction in the inflammation process and enhanced cellular viability. Potential mechanisms of LCN2 involve several pathways including the Janus kinase-2 (JAK2)-signal transducers and the transcription-3 (STAT3) signaling, hypoxia-inducible factor 1-alpha (HIF-1α)-LCN2-vascular endothelial growth factor alpha (VEGFα), and the PKR-like ER kinase (PERK) pathways. LCN2 itself interacts with diverse inflammatory cytokines in TBI and intracranial hemorrhage (ICH), resulting in disruption of the blood-brain barrier, increased programmed cell death, and an imbalance in iron homeostasis. Clinical studies have also shown that increased LCN2 level can act as a prognostic biomarker of outcomes following brain injuries. Therefore, this review aims to comprehensively evaluate the role and underlying mechanisms of LCN2 in brain injuries, including stroke and TBI, and explore potential therapeutic interventions targeting LCN2 in these conditions.

An overview of circulating and urinary biomarkers capable of predicting the transition of acute kidney injury to chronic kidney disease.

INTRODUCTION: Acute kidney injury (AKI) defined by a substantial decrease in kidney function within hours to days and is often irreversible with higher risk to chronic kidney disease (CKD) transition. AREAS COVERED: The authors discuss the diagnostic and predictive utilities of serum and urinary biomarkers on AKI and on the risk of AKI-to-CKD progression. The authors focus on the relevant literature covering evidence of circulating and urinary biomarkers' capability to predict the transition of AKI to CKD. EXPERT OPINION: Based on the different modalities of serum and urinary biomarkers, multiple biomarker panel seems to be potentially useful to distinguish between various types of AKI, to detect the severity and the risk of AKI progression, to predict the clinical outcome and evaluate response to the therapy. Serum/urinary neutrophil gelatinase-associated lipocalin (NGAL), serum/urinary uromodulin, serum extracellular high mobility group box-1 (HMGB-1), serum cystatin C and urinary liver-type fatty acid-binding protein (L-FABP) were the most effective in the prediction of AKI-to-CKD transition regardless of etiology and the presence of critical state in patients. The current clinical evidence on the risk assessments of AKI progression is mainly based on the utility of combination of functional, injury and stress biomarkers, mainly NGAL, L-FABP, HMGB-1 and cystatin C.

Empagliflozin's role in early tubular protection for type 2 diabetes patients.

BACKGROUND: Patients with type 2 diabetes often face early tubular injury, necessitating effective treatment strategies. This study aimed to evaluate the impact of the SGLT2 inhibitor empagliflozin on early tubular injury biomarkers in type 2 diabetes patients with normoalbuminuria. METHODS: A randomized controlled clinical study comprising 54 patients selected based on specific criteria was conducted. Patients were divided into an intervention group (empagliflozin, n = 27) and a control group (n = 27) and treated for 6 weeks. Tubular injury biomarkers KIM-1 and NGAL were assessed pre- and post-treatment. RESULTS: Both groups demonstrated comparable baseline characteristics. Post-treatment, fasting and postprandial blood glucose levels decreased similarly in both groups. The intervention group exhibited better improvements in total cholesterol, low-density lipoprotein, and blood uric acid levels. Renal function indicators, including UACR and eGFR, showed greater enhancements in the intervention group. Significant reductions in KIM-1 and NGAL were observed in the intervention group. CONCLUSION: Treatment with empagliflozin in type 2 diabetes patients with normoalbuminuria led to a notable decrease in tubular injury biomarkers KIM-1 and NGAL. These findings highlight the potential of SGLT2 inhibitors in early tubular protection, offering a new therapeutic approach.

Exploration and verification a 13-gene diagnostic framework for ulcerative colitis across multiple platforms via machine learning algorithms.

Ulcerative colitis (UC) is a chronic inflammatory bowel disease with intricate pathogenesis and varied presentation. Accurate diagnostic tools are imperative to detect and manage UC. This study sought to construct a robust diagnostic model using gene expression profiles and to identify key genes that differentiate UC patients from healthy controls. Gene expression profiles from eight cohorts, encompassing a total of 335 UC patients and 129 healthy controls, were analyzed. A total of 7530 gene sets were computed using the GSEA method. Subsequent batch correction, PCA plots, and intersection analysis identified crucial pathways and genes. Machine learning, incorporating 101 algorithm combinations, was employed to develop diagnostic models. Verification was done using four external cohorts, adding depth to the sample repertoire. Evaluation of immune cell infiltration was undertaken through single-sample GSEA. All statistical analyses were conducted using R (Version: 4.2.2), with significance set at a P value below 0.05. Employing the GSEA method, 7530 gene sets were computed. From this, 19 intersecting pathways were discerned to be consistently upregulated across all cohorts, which pertained to cell adhesion, development, metabolism, immune response, and protein regulation. This corresponded to 83 unique genes. Machine learning insights culminated in the LASSO regression model, which outperformed others with an average AUC of 0.942. This model's efficacy was further ratified across four external cohorts, with AUC values ranging from 0.694 to 0.873 and significant Kappa statistics indicating its predictive accuracy. The LASSO logistic regression model highlighted 13 genes, with LCN2, ASS1, and IRAK3 emerging as pivotal. Notably, LCN2 showcased significantly heightened expression in active UC patients compared to both non-active patients and healthy controls (P < 0.05). Investigations into the correlation between these genes and immune cell infiltration in UC highlighted activated dendritic cells, with statistically significant positive correlations noted for LCN2 and IRAK3 across multiple datasets. Through comprehensive gene expression analysis and machine learning, a potent LASSO-based diagnostic model for UC was developed. Genes such as LCN2, ASS1, and IRAK3 hold potential as both diagnostic markers and therapeutic targets, offering a promising direction for future UC research and clinical application.

Meconium Proteins Involved in Iron Metabolism.

The lack of specific biological materials and biomarkers limits our knowledge of the mechanisms underlying intrauterine regulation of iron supply to the fetus. Determining the meconium content of proteins commonly used in the laboratory to assess the transport, storage, and distribution of iron in the body may elucidate their roles in fetal development. Ferritin, transferrin, haptoglobin, ceruloplasmin, lactoferrin, myeloperoxidase (MPO), neutrophil gelatinase-associated lipocalin (NGAL), and calprotectin were determined by ELISA in meconium samples obtained from 122 neonates. There were strong correlations between the meconium concentrations of haptoglobin, transferrin, and NGAL (p < 0.05). Meconium concentrations of ferritin were several-fold higher than the concentrations of the other proteins, with the exception of calprotectin whose concentration was approximately three-fold higher than that of ferritin. Meconium ceruloplasmin concentration significantly correlated with the concentrations of MPO, NGAL, lactoferrin, and calprotectin. Correlations between the meconium concentrations of haptoglobin, transferrin, and NGAL may reflect their collaborative involvement in the storage and transport of iron in the intrauterine environment in line with their recognized biological properties. High meconium concentrations of ferritin may provide information about the demand for iron and its utilization by the fetus. The associations between ceruloplasmin and neutrophil proteins may indicate the involvement of ceruloplasmin in the regulation of neutrophil activity in the intrauterine environment.

Aberrant activation of hippocampal astrocytes causes neuroinflammation and cognitive decline in mice.

Reactive astrocytes are associated with neuroinflammation and cognitive decline in diverse neuropathologies; however, the underlying mechanisms are unclear. We used optogenetic and chemogenetic tools to identify the crucial roles of the hippocampal CA1 astrocytes in cognitive decline. Our results showed that repeated optogenetic stimulation of the hippocampal CA1 astrocytes induced cognitive impairment in mice and decreased synaptic long-term potentiation (LTP), which was accompanied by the appearance of inflammatory astrocytes. Mechanistic studies conducted using knockout animal models and hippocampal neuronal cultures showed that lipocalin-2 (LCN2), derived from reactive astrocytes, mediated neuroinflammation and induced cognitive impairment by decreasing the LTP through the reduction of neuronal NMDA receptors. Sustained chemogenetic stimulation of hippocampal astrocytes provided similar results. Conversely, these phenomena were attenuated by a metabolic inhibitor of astrocytes. Fiber photometry using GCaMP revealed a high level of hippocampal astrocyte activation in the neuroinflammation model. Our findings suggest that reactive astrocytes in the hippocampus are sufficient and required to induce cognitive decline through LCN2 release and synaptic modulation. This abnormal glial-neuron interaction may contribute to the pathogenesis of cognitive disturbances in neuroinflammation-associated brain conditions.

Urine-derived renal epithelial cells isolated after kidney transplant are sensitive to neutrophil gelatinase-associated lipocalin exposure during in vitro culture.

Urine-derived renal epithelial cells (URECs) are highly voided after kidney transplant and express typical kidney markers, including markers of kidney epithelial progenitor cells. Recently URECs have shown promising immunomodulatory properties when cultured with Peripheral Blood Mononuclear Cells (PBMCs), promoting an increase in the T regulatory cells. In vivo, kidney cells are highly exposed to damage associated molecules during both acute and chronic kidney injury. Neutrophil gelatinase-associated lipocalin (NGAL) is one of the most -known early marker of acute and chronic kidney damage. However, its role on the evolution of renal damage has not yet been fully described, nor has its impact on the characteristics of renal-derived cells during in vitro culture. The aim of this study is to investigate the effect of NGAL on the characteristics of URECs isolated after kidney transplant, by exposing these cells to the treatment with NGAL during in vitro culture and evaluating its effect on UREC viability, proliferation, and immunomodulatory potential. The exposure of URECs to NGAL reduced their viability and proliferative capacity, promoting the onset of apoptosis. The immunomodulatory properties of URECs were partially inhibited by NGAL, without affecting the increase of Treg cells observed during UREC-PBMCs coculture. These results suggest that the exposure to NGAL may compromise some features of kidney stem and specialized cell types, reducing their viability, increasing apoptosis, and partially altering their immunomodulatory properties. Thus, NGAL could represent a target for approaches acting on its inhibition or reduction to improve functional recovery.

Withaferin A protects against epilepsy by promoting LCN2-mediated astrocyte polarization to stopping neuronal ferroptosis.

BACKGROUND: Epilepsy is among the most frequent severe brain diseases, with few treatment options available. Neuronal ferroptosis is an important pathogenic mechanism in epilepsy. As a result, addressing ferroptosis appears to be a promising treatment approach for epilepsy. Withaferin A (WFA) is a C28 steroidal lactone that has a broad range of neuroprotective properties. Nonetheless, the antiepileptic action of WFA and the intrinsic mechanism by which it inhibits ferroptosis following epilepsy remain unknown. PURPOSE: This study aimed at investigating to the antiepileptic potential of WFA in epilepsy, as well as to propose a potential therapeutic approach for epilepsy therapy. METHODS: We conducted extensive research to examine the impacts of WFA on epilepsy and ferroptosis, using the kainic acid (KA)-treated primary astrocyte as an in vitro model and KA-induced temporal lobe epilepsy mice as an in vivo model. To analyze the neuroprotective effects of WFA on epileptic mice, electroencephalogram (EEG) recording, Nissl staining, and neurological function assessments such as the Morris water maze (MWM) test, Y-maze test, Elevated-plus maze (O-maze) test, and Open field test were used. Furthermore, the mechanism behind the neuroprotective effect of WFA in epilepsy was investigated using the transcriptomics analysis and verified on epileptic patient and epileptic mouse samples using Western blotting (WB) and immunofluorescence (IF) staining. In addition, WB, IF staining and specific antagonists/agonists were used to investigate astrocyte polarization and the regulatory signaling pathways involved. More critically, ferroptosis was assessed utilizing lipocalin-2 (LCN2) overexpression cell lines, siRNA knockdown, JC-1 staining, WB, IF staining, flow cytometry, electron microscopy (TEM), and ferroptosis-related GSH and MDA indicators. RESULTS: In this study, we observed that WFA treatment reduced the number of recurrent seizures and time in seizure, and the loss of neurons in the hippocampal area in in epileptic mice, and even improved cognitive and anxiety impairment after epilepsy in a dose depend. Furthermore, WFA treatment was proven to enhance to the transformation of post-epileptic astrocytes from neurotoxic-type A1 to A2 astrocytes in both in vivo and in vitro experiments by inhibiting the phosphoinositide 3-kinase /AKT signaling pathway. At last, transcriptomics analysis in combination with functional experimental validation, it was discovered that WFA promoted astrocyte polarity transformation and then LCN2 in astrocytes, which inhibited neuronal ferroptosis to exert neuroprotective effects after epilepsy. In addition, we discovered significant astrocytic LCN2 expression in human TLE patient hippocampal samples. CONCLUSIONS: Taken together, for the first, our findings suggest that WFA has neuroprotective benefits in epilepsy by modulating astrocyte polarization, and that LCN2 may be a novel potential target for the prevention and treatment of ferroptosis after epilepsy.

Urine biomarkers in type 2 diabetes mellitus with or without microvascular complications.

OBJECTIVE: To investigate the distribution of nine (9) urine biomarkers in people living with type 2 diabetes mellitus (T2DM), with or without microvascular complications. METHODS: In total, 407 people with T2DM were enrolled from 2021 to 2022. According to diabetic retinopathy (DR) and urinary albumin-creatinine ratio (UACR), the 407 people were divided into four (4) groups, DR(-)UACR(-), DR(+)UACR(-), DR(-)UACR(+), and DR( + )UACR(+). In addition, 112 healthy volunteers were enrolled during the same period. The nine (9) urine markers included α1-microglobulin (u-α1MG), immunoglobulin G (u-IgG), neutrophil gelatinase-associated lipid carrier protein (u-NGAL), cystatin C (u-CysC), retinol-binding protein (u-RBP), ß2-microglobulin (u-ß2MG), N-acetyl-ß-D-glucosaminidase (u-NAG), transferrin (u-Trf), and collagen type IV (u-Col). For each marker, the respective level of 97.5 percentile in healthy volunteers was taken as an upper reference limit. RESULTS: Among the 407 people, 248 individuals (61%) were DR(-)UACR(-), 100 (25%) were DR(-)UACR(+), 37 (9%) were DR(+)UACR(-), and 22 (5%) were DR(+)UACR(+). The u-NAG/Cr biomarker level showed a significant difference between healthy participants and people with T2DM. In the DR(-)UACR(-)group, u-Trf/Cr showed the highest positive rate (21.37%), followed by u-IgG/Cr (14.52%); u-NAG/Cr (10.48%); u-ß2MG/Cr (4.44%); u-CysC/Cr (4.03%); u-NGAL/Cr (4.03%); u-RBP/Cr (2.82%); u-α1MG/Cr (2.42%); 17.34% of people with T2DM showed multiple biomarkers positive (≥2 biomarkers). The positive rates of one biomarker (21.33%) and two biomarkers (18.67%) in people who have less than five (5) years of T2DM were almost close to those of the DR(-)UACR(-) group (21.37%, and 12.10%, respectively). CONCLUSION: Renal tubule biomarkers may be used as an indicator in the early detection and monitoring of renal injury in diabetes mellitus. The u-NAG biomarker should be measured for the people with T2DM of the first-time diagnosis.

Astrocyte-secreted lipocalin-2 elicits bioenergetic failure-induced neuronal death that is causally related to high fatality in a mouse model of hepatic encephalopathy.

Hepatic encephalopathy (HE) is a neurological complication arising from acute liver failure with poor prognosis and high mortality; the underlying cellular mechanisms are still wanting. We previously found that neuronal death caused by mitochondrial dysfunction in rostral ventrolateral medulla (RVLM), which leads to baroreflex dysregulation, is related to high fatality in an animal model of HE. Lipocalin-2 (Lcn2) is a secreted glycoprotein mainly released by astrocytes in the brain. We noted the presence of Lcn2 receptor (Lcn2R) in RVLM neurons and a parallel increase of Lcn2 gene in astrocytes purified from RVLM during experimental HE. Therefore, our guiding hypothesis is that Lcn2 secreted by reactive astrocytes in RVLM may underpin high fatality during HE by eliciting bioenergetic failure-induced neuronal death in this neural substrate. In this study, we first established the role of astrocyte-secreted Lcn2 in a liver toxin model of HE induced by azoxymethane (100 µg/g, ip) in C57BL/6 mice, followed by mechanistic studies in primary astrocyte and neuron cultures prepared from postnatal day 1 mouse pups. In animal study, immunoneutralization of Lcn2 reduced apoptotic cell death in RVLM, reversed defunct baroreflex-mediated vasomotor tone and prolonged survival during experimental HE. In our primary cell culture experiments, Lcn2 produced by cultured astrocytes and released into the astrocyte-conditioned medium significantly reduced cell viability of cultured neurons. Recombinant Lcn2 protein reduced cell viability, mitochondrial ATP (mitoATP) production, and pyruvate dehydrogenase (PDH) activity but enhanced the expression of pyruvate dehydrogenase kinase (PDK) 1, PDK3 and phospho-PDHA1 (inactive PDH) through MAPK/ERK pathway in cultured neurons, with all cellular actions reversed by Lcn2R knockdown. Our results suggest that astrocyte-secreted Lcn2 upregulates PDKs through MAPK/ERK pathway, which leads to reduced PDH activity and mitoATP production; the reinforced neuronal death in RVLM is causally related to baroreflex dysregulation that underlies high fatality associated with HE.