OBJECTIVE: To explore the contribution of ferroptosis to myocardial injury in mouse models of sepsis and the role lipocalin-2 (Lcn2) in ferroptosis. METHODS: Adult male C57BL/6 mice were randomized equally into sham-operated group, cecal ligation and puncture (CLP)-induced sepsis group, and CLP + Fer-1 group where the mice received intraperitoneal injection of 5 mg/mL Fer-1 (5 mg/kg) 1 h before CLP. The left ventricular functions (including LVEF%, LVFS%, LVIDd and LVIDs) of the mice were assessed by echocardiography at 24 h after CLP. Myocardial injury in the mice was observed with HE staining, and the changes of myocardial ultrastructure and mitochondria were observed using transmission electron microscopy (TEM). Serum TNF-α level was measured with ELISA, and the changes of myocardial iron content were detected using tissue iron kit. The protein expressions of myocardial Lcn2, glutathione peroxidase 4 (GPX4) and ferroptosis suppressor protein 1 (FSP1) were determined with Western blotting. RESULTS: The septic mice showed significantly decreased LVEF%, LVFS% and LVIDd and increased LVIDs at 24 h after CLP (P < 0.05), and these changes were significantly improved by Fer-1 treatment. Sepsis caused obvious myocardial pathologies and changes in myocardial ultrastructure and mitochondria, which were significantly improved by Fer-1 treatment. Fer-1 treatment also significantly ameliorated sepsis-induced elevations of serum TNF-α level, myocardial tissue iron content, and Lcn2 protein expression and the reduction of GPX4 and FSP1 protein expression levels (P < 0.05). CONCLUSION GPX4- and FSP1-mediated ferroptosis are involved in myocardial injury in mice with CLP-induced sepsis, and inhibition of ferroptosis can attenuate septic myocardial injury, in which Lcn2 may play a role.
Animals ; Ferroptosis ; Heart Injuries ; Lipocalin-2 ; Male ; Mice ; Mice, Inbred C57BL ; Sepsis/metabolism*

OBJECTIVES: The excretion of urinary vitamin D-binding protein (uVDBP) is related to the occurrence and development of early-stage renal damage in patients with Type 2 diabetes (T2DM). This study aims to explore the significance of detecting uVDBP in T2DM patients and its relationship with renal tubules, and to provide a new direction for the early diagnosis of T2DM renal damage. METHODS: A total of 105 patients with T2DM, who met the inclusion criteria, were included as a patient group, and recruited 30 individuals as a normal control group. The general information and blood and urine biochemical indicators of all subjects were collected; the levels of uVDBP, and a marker of tubular injury [urine kidney injury molecule 1 (uKIM-1), urine neutrophil gelatinase-associated lipocalin (uNGAL) and urine retinol-binding protein (uRBP)] were detected by enzyme-linked immunosorbent assay. The results were corrected by urinary creatinine (Cr) to uVDBP/Cr, uKIM-1/Cr, uNGAL/Cr and uRBP/Cr. The Pearson's and Spearman's correlation tests were used to analyze the correlation between uVDBP/Cr and urine albumin-to-creatinine ratio (UACR), estimated glomerular filtration rate (eGFR) and markers of tubular injury, and multivariate linear regression and receiver operating characteristic curve were used to analyze the correlation between uVDBP/Cr and UACR or eGFR. RESULTS: Compared with the normal control group, the uVDBP/Cr level in the patient group was increased (P<0.05), and which was positively correlated with UACR (r=0.774, P<0.01), and negatively correlated with eGFR (r=-0.397, P<0.01). There were differences in the levels of uKIM-1/Cr, uNGAL/Cr, and uRBP/Cr between the 2 groups (all P<0.01). The uVDBP/Cr was positively correlated with uKIM-1/Cr (r=0.752, P<0.01), uNGAL/Cr (r=0.644, P<0.01) and uRBP/Cr (r=0.812, P<0.01). The sensitivity was 90.0% and the specificity was 82.9% (UACR>30 mg/g) for evaluation of uVDBP/Cr on T2DM patients with early-stage renal damage, while the sensitivity was 75.0% and the specificity was 72.6% for evaluation of eGFR on T2DM patients with early-stage renal damage. CONCLUSIONS The uVDBP/Cr can be used as a biomarker in early-stage renal damage in T2DM patients.
Humans ; Diabetes Mellitus, Type 2/complications* ; Creatinine ; Vitamin D-Binding Protein/urine* ; Lipocalin-2/urine* ; Kidney/metabolism* ; Glomerular Filtration Rate ; Biomarkers

OBJECTIVETo investigate the expression and clinical significance of matrix metalloproteinase-9 and its complex in the urine of the patient with breast cancer.

METHODSUsing substract gel electrophoresis and western-blot analysis, expressions of MMP-9 and MMP-9/NGAL complex in breast cancer (n = 97), breast benign (n = 41) and normal (n = 60) were observed.

RESULTSThere MMP-9 and MMP-9/NGAL complex expressions were 76.29% and 64.95% in breast cancer, 46.34% and 43.90% in breast benign, and 23.33% in normal respectively. The MMP-9 and MMP-9/NGAL complex expressions were higher in breast cancer than those in breast benign and in normal (chi(2) = 7.456, P < 0.01). MMP-9 and MMP-9/NGAL complex expressions in urine of breast cancer had not any relationship with tumor size, TNM stage, patient age, menopause status as well as ER status, but was correlated to lymphatic node status (chi(2) = 5.206, P < 0.05).

CONCLUSIONSMMP-9 and MMP-9/NGAL complex expressions in urine are significant in estimating lymphatic node metastasis in breast cancer and a valuable early prognostic factors and screening in breast cancer.

Acute-Phase Proteins ; Blotting, Western ; Breast Neoplasms ; pathology ; urine ; Carrier Proteins ; urine ; Female ; Humans ; Lipocalin-2 ; Lipocalins ; Lymphatic Metastasis ; Matrix Metalloproteinase 9 ; urine ; Oncogene Proteins ; Proto-Oncogene Proteins

Acute-Phase Proteins ; metabolism ; Animals ; Female ; Hepatitis, Autoimmune ; immunology ; metabolism ; pathology ; Interleukin-17 ; metabolism ; Lipocalin-2 ; Lipocalins ; metabolism ; Liver ; pathology ; Mice ; Mice, Inbred BALB C ; Oncogene Proteins ; metabolism

PURPOSE: To investigate the clinical value of urine interleukin-18 (IL-8), neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) for the early diagnosis of acute kidney injury (AKI) in patients with ureteroscopic lithotripsy (URL) related urosepsis. METHODS: A retrospective study was carried out in 157 patients with urosepsis after URL. The patients were divided into AKI group and non-AKI group according to the Kidigo guideline and urine IL-8, NGAL and KIM-1 levels were detected by enzyme-linked immunosorbent assay at 0, 4, 12, 24 and 48 h after the surgery. Receiver operating characteristic curve (ROC) was used to evaluate the diagnostic value of these three biomarkers for postoperative AKI. RESULTS: The level of urine IL-8, NGAL and KIM-1 in AKI group was significantly higher than that in non-AKI group at 4, 12, 24 and 48 h (p < 0.01). The ROC analysis showed the combined detection of urine IL-8, NGAL and KIM-1 at 12 h had a larger area under curve (AUC) than a single marker (0.997, 95% CI: 0.991-0.998), and the sensitivity and specificity were 98.2% and 96.7%, respectively. Pearson correlation analysis showed that the levels of urine NGAL at 4, 12, 24 and 48 h in AKI patients were positively correlated with the levels of urine KIM-1 and IL-18 (p < 0.01). CONCLUSION AKI could be quickly recognized by the elevated level of urine IL-8, NGAL and KIM-1 in patients with URL-related urosepsis. Combined detection of the three urine biomarkers at 12 h after surgery had a better diagnostic performance, which may be an important reference for the early diagnosis of AKI.
Acute Kidney Injury/etiology* ; Biomarkers ; Early Diagnosis ; Hepatitis A Virus Cellular Receptor 1 ; Humans ; Interleukin-18 ; Interleukin-8 ; Lipocalin-2 ; Lithotripsy ; Retrospective Studies ; Ureteroscopy

Neutrophil gelatinase-associated lipocalin (NGAL) is a member of the lipocalin family. As a novel adipokine, it widely presents in the tissues under the condition of metabolic disorders. More and more studies suggest that NGAL might be a marker for a variety of diseases associated with lipid metabolism. It is likely that NGAL plays an important role in obese-inflammation-induced metabolic syndrome,insulin resistance, glucose and lipid metabolism, endothelial dysfunction and atherosclerosis pathway.
Acute-Phase Proteins ; metabolism ; Atherosclerosis ; Biomarkers ; metabolism ; Humans ; Inflammation ; Insulin Resistance ; Lipocalin-2 ; Lipocalins ; metabolism ; Metabolic Syndrome ; metabolism ; physiopathology ; Obesity ; Proto-Oncogene Proteins ; metabolism

The incidence rate of anxiety and depression is significantly higher in patients with inflammatory bowel diseases (IBD) than in the general population. The mechanisms underlying dextran sulfate sodium (DSS)-induced depressive-like behaviors are still unclear. We clarified that IBD mice induced by repeated administration of DSS presented depressive-like behaviors. The paraventricular thalamic nucleus (PVT) was regarded as the activated brain region by the number of c-fos-labeled neurons. RNA-sequencing analysis showed that lipocalin 2 (Lcn2) was upregulated in the PVT of mice with DSS-induced depressive behaviors. Upregulating Lcn2 from neuronal activity induced dendritic spine loss and the secreted protein induced chemokine expression and subsequently contributed to microglial activation leading to blood-brain barrier permeability. Moreover, Lcn2 silencing in the PVT alleviated the DSS-induced depressive-like behaviors. The present study demonstrated that elevated Lcn2 in the PVT is a critical factor for DSS-induced depressive behaviors.
Mice ; Humans ; Animals ; Lipocalin-2/genetics* ; Midline Thalamic Nuclei ; Brain ; Inflammatory Bowel Diseases ; Proto-Oncogene Proteins c-fos ; Mice, Inbred C57BL

INTRODUCTION: Creatinine has limitations in identifying and predicting acute kidney injury (AKI). Our study examined the utility of neutrophil gelatinase-associated lipocalin (NGAL) in predicting AKI in patients presenting to the emergency department (ED), and in predicting the need for renal replacement therapy (RRT), occurrence of major adverse cardiac events (MACE) and all-cause mortality at three months post visit. METHODS: This is a single-centre prospective cohort study conducted at Singapore General Hospital (SGH). Patients presenting to SGH ED from July 2011 to August 2012 were recruited. They were aged ≥21 years, with an estimated glomerular filtration rate <60 mL/min/1.73 m², and had congestive cardiac failure, systemic inflammatory response syndrome or required hospital admission. AKI was diagnosed by researchers blinded to experimental measurements. Serum NGAL was measured as a point-of-care test. RESULTS: A total of 784 patients were enrolled, of whom 107 (13.6%) had AKI. Mean serum NGAL levels were raised (P < 0.001) in patients with AKI (670.0 ± 431.9 ng/dL) compared with patients without AKI (490.3 ± 391.6 ng/dL). The sensitivity and specificity of NGAL levels >490 ng/dL for AKI were 59% (95% confidence interval [CI] 49%-68%) and 65% (95% CI 61%-68%), respectively. Need for RRT increased 21% per 100 ng/dL increase in NGAL (P < 0.001), whereas odds of death in three months increased 10% per 100 ng/dL increase in NGAL (P = 0.028). No clear relationship was observed between NGAL levels and MACE. CONCLUSION Serum NGAL identifies AKI and predicts three-month mortality.
Humans ; Lipocalin-2 ; Prospective Studies ; Lipocalins ; Proto-Oncogene Proteins ; Acute-Phase Proteins ; Biomarkers ; Acute Kidney Injury/diagnosis* ; Emergency Service, Hospital ; Predictive Value of Tests

OBJECTIVETo investigate the urinary neutrophil gelatinase-associated lipocalin (NGAL) concentration in children with idiopathic nephrotic syndrome (INS) and its clinical significance.

METHODSThirty-four children newly diagnosed with INS received oral prednisone for 4 weeks. Patients whose urinary protein did not become negative were classified as steroid-resistant nephrotic syndrome (SRNS) group, while those whose urinary protein did become negative were classified as steroid-sensitive nephrotic syndrome (SSNS) group. Morning midstream urine specimens were collected from all patients before use of prednisone and after 1, 2, 3, and 4 weeks of treatment with prednisone. Enzyme-linked immunosorbent assay was used to measure the urinary NGAL concentration. Meanwhile, urinary creatinine (Cr) concentration was measured, and urinary NGAL concentration in a single urine collection was adjusted according to the urinary Cr excretion. The two groups were compared in terms of urinary NGAL/Cr ratio.

RESULTSCompared with the SRNS group, the SSNS group had significantly decreased urinary NGAL/Cr ratios after 3 and 4 weeks of prednisone treatment (P < 0.05). Compared with the SRNS group, the SSNS group had a significantly decreased urinary β2-MG/Cr ratio after 4 weeks of prednisone treatment (P < 0.05). In both groups, urinary NGAL/Cr ratio was positively correlated with urinary protein/Cr ratio (r = 0.510, P < 0.01). The results of ROC curve analysis showed when diagnostic cut-off point of urinary NGAL/Cr was 0.043 by 3 weeks after treatment, sensitivity and specificity achieved 100% and 79.2% respectively.

CONCLUSIONSUrinary NGAL/Cr ratio remains high in children with SRNS, while this ratio decreases gradually during prednisone treatment in children with SSNS, and it falls ahead of urinary β2-MG/Cr ratio. These results suggest that dynamic monitoring of urinary NGAL/Cr ratio is useful for early judgment of response to prednisone in patients with INS.

Acute-Phase Proteins ; urine ; Child ; Child, Preschool ; Creatinine ; urine ; Female ; Humans ; Lipocalin-2 ; Lipocalins ; urine ; Male ; Nephrotic Syndrome ; drug therapy ; urine ; Prednisone ; therapeutic use ; Proto-Oncogene Proteins ; urine ; beta 2-Microglobulin ; urine

OBJECTIVETo explore whether the amount of lipocalin-2 in the biofluid could reflect the onset of sepsis-induced acute lung injury (ALI) in mice.

METHODSLipopolysaccharide (LPS, 10 mg/kg) injection or cecal ligation and puncture (CLP) was performed to induce severe sepsis and ALI in C57 BL/6 male mice randomly divided into 5 groups (n=10 in each group): group A (intraperitoneal LPS injection), group B (intravenous LPS injection via tail vein), group C (CLP with 25% of the cecum ligated), group D (CLP with 75% of the cecum ligated), and the control group (6 sham-operation controls plus 4 saline controls). All the mice received volume resuscitation. Measurements of pulmonary morphological and functional alterations were used to identify the presence of experimental ALI. The expressions of lipocalin-2 and interleukin (IL)-6 in serum, bronchoalveolar lavage fluid (BALF), and lung tissue were quantified at both protein and mRNA levels. The overall abilities of lipocalin-2 and IL-6 tests to diagnose sepsis-induced ALI were evaluated by generating receiver operator characteristic curves (ROC) and computing area under curve (AUC).

RESULTSIn both group B and group D, most of the main features of experimental ALI were reproduced in mice, while group A and group C showed septic syndrome without definite evidence for the presence of ALI. Compared with septic mice without ALI (group A+group C), lipocalin-2 protein expression in septic mice with ALI (group B+group D) was significantly up-regulated in BALF (P<0.01) and in serum (P<0.01), and mRNA expression boosted in lung tissues (all P<0.05). Lipocalin-2 tests performed better than IL-6 tests in recognizing sepsis-induced ALI cases, evidenced by the larger AUC of the former (BALF tests, 0.8800 versus 0.6625; serum tests, 0.8500 versus 0.7000). Using a dual cutoff system to diagnose sepsis-induced ALI, BALF lipocalin-2 test exhibited the highest positive likelihood ratio (13.000) and the lowest negative likelihood ratio (0.077) among the tests of lipocalin-2 and IL-6 in blood and BALF. A statistically significant correlation was found between lipocalin-2 concentration in BALF and that in serum (Spearman r=0.8803, P<0.0001).

CONCLUSIONSLipocalin-2 expression is significantly up-regulated in septic ALI mice compared with those without ALI. Lipocalin-2 tests with a dual cutoff system could be an effective tool in distinguishing experimental ALI cases.

Acute-Phase Proteins ; metabolism ; Animals ; Base Sequence ; Bronchoalveolar Lavage Fluid ; DNA Primers ; Lipocalin-2 ; Lipocalins ; metabolism ; Lung Injury ; complications ; diagnosis ; Male ; Mice ; Mice, Inbred C57BL ; Oncogene Proteins ; metabolism ; Real-Time Polymerase Chain Reaction ; Sepsis ; complications