Tissue Inhibitor Metalloproteinase-2 Research Articles

Tissue Inhibitor Metalloproteinase-2·IGF-Binding Protein 7 for the Prediction of Acute Kidney Injury following Cardiac Surgery

Introduction: Cardiac surgery-associated acute kidney injury (CSA-AKI) is a common complication associated with increased morbidity and mortality. Tissue inhibitor metalloproteinase-2·insulin-like growth factor-binding protein 7 (TIMP-2·IGFBP7) determines tubular stress markers, which may occur prior to tubular damage. Previous studies on the use of TIMP-2·IGFBP7 for the prediction of CSA-AKI showed divergent results. Therefore, this study aimed to explore the predictive value of TIMP-2·IGFBP7 measurements for the early detection of acute kidney injury (AKI) and short-term adverse outcomes after cardiac surgery. Methods: In the prospective cohort study, blood and urine samples were collected 6–12 h after cardiac surgery. Blood samples to monitor serum creatinine levels were additionally extracted from days 1 to 7. AKI was defined based on the KDIGO consensus guidelines. AKI within 7 days following surgery was the primary outcome. The initiation of renal replacement therapy, in intensive care unit mortality, and the combination of both were secondary outcomes. Results: A total of 557 patients were enrolled; 134 (24.06%) of them developed AKI and 33 (5.9%) had moderate or severe AKI. AKI developed more frequently in elderly patients with diabetes or with higher baseline serum creatinine levels. Patients with AKI had higher EuroSCORE II, Cleveland Clinic Score, and simplified renal index (SRI) than those without AKI. Urinary TIMP-2·IGFBP7 was significantly higher in patients with AKI. The area under the curve was 0.66 in predicting all AKI and 0.70 in predicting stages 2 and 3 AKI. The resulting sensitivity and specificity were 44.0% and 83.9%, respectively, for a calculated threshold TIMP-2·IGFBP7 value of 0.265 (ng/mL)2/1,000. The TIMP-2·IGFBP7 values, SRI score, and age were significantly associated with AKI within 7 days postoperatively. A total of 33 patients reached the composite endpoint; the percentage of patients who reached the composite endpoint in the TIMP-2·IGFBP7 of >0.265 (ng/ml)2/1,000 group was significantly higher than that of ≤0.265 (ng/mL)2/1,000 group. Conclusions: Postoperative implementation of TIMP-2·IGFBP7 improved the prediction of CSA-AKI and may aid in identifying patients at risk of short-term adverse outcomes. We identified an ideal calculated cutoff value of 0.265 (ng/mL)2/1,000 for the prediction of CSA-AKI among all AKI patients.

Acute Kidney Injury and Sepsis after Cardiac Surgery: The Roles of Tissue Inhibitor Metalloproteinase-2, Insulin-like Growth Factor Binding Protein-7, and Mid-Regional Pro-Adrenomedullin.

Identifying a panel of markers detecting kidney injury before the glomerular filtration rate reduction is a challenge to improving the diagnosis and management of acute kidney injury (AKI) in septic patients. This study evaluated the roles of tissue inhibitor metal proteinase-2, insulin growth factor binding protein-7 (TIMP2*IGFBP7), and mid-regional pro-adrenomedullin (MR-proADM) in patients with AKI. This study was prospectively conducted in an intensive care unit (ICU) enrolling 230 patients who underwent cardiac surgery. Biomarkers were evaluated before and after 4 h of the cardiac surgery. Whereas urine and creatinine alterations appeared at 23.2 (12.7-36.5) hours after cardiac surgery, urinary TIMP2*IGBP7 levels were higher at 4 h in AKI patients (1.1 ± 0.4 mg/L vs. 0.08 ± 0.02 mg/L; p < 0.001). Its concentration > 2 mg/L increases AKI risk within the following 24 h, clearly identifying the population at high risk of renal replacement therapy (RRT). In patients with sepsis, MR-proADM levels were 2.3 nmol/L (0.7-7.8 nmol/L), with the highest values observed in septic shock patients (5.6 nmol/L (3.2-18 nmol/L)) and a better diagnostic profile than procalcitonin and C-reactive protein to identify septic patients. MR-proADM values > 5.1 nmol/L and urine TIMP2*IGBP7 levels > 2 mg/L showed a significantly faster progression to RRT, with a mean follow-up time of 1.1 days. TIMP2*IGBP7 and MR-proADM precociously diagnose AKI in septic patients after cardiac surgery, giving prognostic information for RRT requirement.

Predictive value of urinary cell cycle arrest biomarkers for all cause-acute kidney injury: a meta-analysis

The cell cycle arrest markers tissue inhibitor metalloproteinases-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7) have been identified as potential biomarkers of acute kidney injury (AKI) in critically ill adults in intensive care units and cardiac surgery-associated AKI (CSA-AKI). However, the clinical impact on all-cause AKI remains unclear. Here, we report a meta-analysis performed to evaluate the predictive value of this biomarker for all-cause AKI. The PubMed, Cochrane, and EMBASE databases were systematically searched up to April 1, 2022. We used the Quality Assessment Tool for Diagnosis Accuracy Studies (QUADAS-2) to assess the quality. We extracted useful information from these studies and calculated the sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC). Twenty studies with 3625 patients were included in the meta-analysis. The estimated sensitivity of urinary [TIMP-2] × [IGFBP7] in the diagnosis of all-cause AKI was 0.79 (95% CI 0.72, 0.84), and the specificity was 0.70 (95% CI 0.62, 0.76). The value of urine [TIMP-2] × [IGFBP7] in the early diagnosis of AKI was assessed using a random effects model. The pooled positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were 2.6 (95% CI 2.1, 3.3), 0.31 (95% CI 0.23, 0.40), and 8 (95% CI 6, 13), respectively. The AUROC was 0.81 (95% CI 0.78–0.84). No significant publication bias was observed in eligible studies. Subgroup analysis indicated that the diagnostic value was related to the severity of AKI, time measurement, and clinical setting. This study shows that urinary [TIMP-2] × [IGFBP7] is a reliable effective predictive test for all cause-AKI. However, whether and how urinary [TIMP-2] × [IGFBP7] can be used in clinical diagnosis still requires further research and clinical trials.

Tissue Inhibitor Metalloproteinase-2 and Insulin-Like Growth Factor Binding Protein-7 Kinetics Following Exposure to High-Dose Methotrexate.

Key Points Urinary TIMP2×IGFBP7 (uTIMP2×IGFBP7) concentrations experienced a rapid and sustained decline after high-dose methotrexate (MTX) exposure.uTIMP2×IGFBP7 kinetics and concentrations after high-dose MTX exposure demonstrated no utility in predicting AKI.

Urine Biomarkers in the Management of Adult Neurogenic Lower Urinary Tract Dysfunction: A Systematic Review.

Neurogenic lower urinary tract dysfunction requires lifelong surveillance and management for the perseveration of patients' quality of life and the prevention of significant morbidity and mortality. Urine biomarkers are an attractive noninvasive method of surveillance for these patients. The aim of this systematic review is to search for and critically appraise studies that investigate the clinical usefulness of urine biomarkers in the management of neurogenic lower urinary tract dysfunction (NLUTD) in adults. This review was conducted according to PRISMA and MOOSE guidelines. Search strategy included PubMed, CENTRAL, and Scopus (until October 2022). Studies investigating potential urine biomarkers for the management of adults with NLUTD were included. Fifteen studies fulfilled the criteria. To date, a variety of different urine molecules have been investigated for the diagnosis and management of neurogenic overactive bladder and detrusor overactivity (nerve growth factor, brain-derived neurotrophic factor, prostaglandin E2, prostaglandin F2α, transformation growth factor β-1, tissue inhibitor metalloproteinase-2, matrix metalloproteinase-2, substance P, microRNA), diagnosis of vesicoureteral reflux (exosomal vitronectin), urinary tract infection (neutrophil gelatinase-associated lipocalin, interleukin 6) and bladder cancer screening (cytology, BTA stat, survivin) in neurological patients. Further studies are needed to specify the utility of each molecule in the management algorithm of adult NLUTD.

The novel biomarker circ_0020339 drives septic acute kidney injury by targeting miR-17-5p/IPMK axis.

Sepsis is a systemic life-threatening inflammatory disease, which leads to septic acute kidney injury (AKI). Circular RNAs (circRNAs) are involved in septic AKI. Herein, we aimed to expound the action of circ_0020339 in septic AKI. The dysregulation of plasma circRNAs between patients with septic non-AKI and patients with septic AKI were screened by circRNA chip. The dysregulation of circ_0020339, microRNA (miR)-17-5p, and inositol polyphosphate multi kinase (IPMK) mRNA was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability and apoptosis were measured by cell counting kit-8 (CCK-8) and flow cytometry, respectively. The release of serum creatinine (SCr), tissue inhibitor metalloproteinase-2 (TIMP-2), insulin-like growth factor binding protein-7 (IGFBP7),tumor necrosis factor (TNF)α and interleukin (IL)-1β was evaluated by enzyme-linked immunosorbent assay (ELISA). Bioinformatic analysis, dual-luciferase reporter assay and miRNA pull down assay were used to confirm the interaction between miR-17-5p and circ_0020339 or IPMK 3'untranslated region (UTR). Protein level of IPMK, TNF receptor-associated factor 6 (TRAF6), phosphorylated AKT (p-AKT)/total (t)-AKT, p-nuclear factor kappa-B (NF-κB) kinase (p-IKK)/t-IKK, p-inhibitor ofNF-κB (p-IκB)α/t-IκBα, and p-p65/t-p65 were conducted by western blot. Circ_0020339 was upregulated in the plasma of patients with septic AKI as well as LPS-treated HK2 cells and C57BL/6 mice relative to the corresponding counterparts. Functionally, circ_0020339 was positively correlated with markers of renal functional injury and inflammation in patients with septic AKI; si-circ_0020339 facilitated cell proliferation, while restrained cell apoptosis and inflammation in LPS-triggered HK2 cells; meanwhile, si-circ_0020339 restrained survival rate, renal functional injury and inflammation in LPS-triggered C57BL/6 mice. Furthermore, circ_0020339 and IPMK 3'UTR shared the same complementary sites with miR-17-5p. si-circ_0020339 attenuated LPS-induced cell damage by targeting miR-17-5p/IPMK axis and inactivation of TRAF6/p-AKT/p-IKK/p-IκBα/p-p65. Altogether, plasma circ_0020339 serves as a novel diagnostic marker of patients with septic AKI.

Evaluating TIMP-2 and IGFBP-7 as a predictive tool for kidney injury in ureteropelvic junction obstruction.

ABSTRACTA major challenge in the management of ureteropelvic junction obstruction (UPJO) is the selection of patients who would benefit from surgical treatment. Tissue inhibitor metalloproteinase-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7) indicate renal cell stress and are associated with cell cycle arrest. The [TIMP-2] [IGFBP7] ratio (Nephrocheck®) has been recently applied in patients in intensive care units patients to predict the development of acute kidney injury. In this study, we evaluated the performance of these biomarkers performance to distinguishing obstructive hydronephrosis (HN) from non-obstructive HN.Materials and Methods:Consecutive patients with UPJO were enrolled in this study. Urinary [TIMP-2] [IGFBP7] and clinical characteristics (hydronephrosis grade, differential renal function, and drainage half-time) were measured in the following groups: 26 children with obstructive HN at initial diagnosis (group 1A) and after six months of dismembered pyeloplasty (group 1B); 22 children with non-obstructive HN (group 2), and 26 children without any urinary tract condition, as the control group (group 3).Results:Comparing the initial samples, [TIMP-2] [IGFBP7] had higher levels in the HN groups and lower levels in the control group; however, no difference was observed between the HN groups (obstructive vs. non-obstructive). After six months of follow-up, patients who underwent dismembered pyeloplasty showed stability in the urinary concentration of [TIMP-2] [IGFBP7]. All patients with [TIMP-2] [IGFBP7] higher than 1.0 (ng/mL)2/1000 had diffuse cortical atrophy on ultrasonography.Conclusions:We showed that urinary levels of urinary [TIMP-2] [IGFBP7] are higher in children with HN than controls. Nephrocheck® is not reliable in predicting the need for surgical intervention for pediatric patients with UPJO.

Evaluation of acute kidney injury by urinary tissue inhibitor metalloproteinases-2 and insulin-like growth factor-binding protein 7 after pediatric cardiac surgery.

With adult patients, the measurement of [TIMP-2]*[IGFBP7] can predict the risk of moderate to severe AKI within 12h of testing. In pediatrics, however, the performance of [TIMP-2]*[IGFBP7] as a predictor of AKI was less studied and yet to be widely utilized in clinical practice. This study was conducted to validate the utility of [TIMP-2]*[IGFBP7] as an earlier biomarker for AKI prediction in Chinese infants and small children. We measured urinary [TIMP-2]*[IGFBP7] using NEPHROCHECK® at eight perioperative time points in 230 patients undergoing complex cardiac surgery and evaluated the performance of [TIMP-2]*[IGFBP7] for predicting severe AKI within 72h of surgery. A total of 50 (22%) of 230 developed AKI stages 2-3 within 72h after CPB initiation. In the AKI stage 2-3 patients, two patterns of serum creatinine (SCr) elevations were observed. The patients with only a transient increase in SCr within 24h (&lt; 24h, early AKI 2-3) did not experience a worse outcome than patients in AKI stage 0-1. AKI stage 2-3 patients with SCr elevation after 24h (24-72h, late AKI 2-3), as well as AKI dialysis patients (together designated severe AKI), did experience worse outcomes. Compared to AKI stages 0-1, significant elevations of [TIMP-2]*[IGFBP7] values were observed in severe AKI patients at hours T2, T4, T12, and T24 following CPB initiation. The AUC for predicting severe AKI with [TIMP-2]*[IGFBP7] at T2 (AUC = 0.76) and maximum T2/T24 (AUC = 0.80) are higher than other time points. The addition of the NEPHROCHECK® test to the postoperative parameters improved the risk assessment of severe AKI. Multiple AKI phenotypes (early versus late AKI) were identified after pediatric complex cardiac surgery according to SCr-based AKI definition. Urinary [TIMP-2]*[IGFBP7] predicts late severe AKI (but not early AKI) as early as 2h following CPB initiation. A higher resolution version of the Graphical abstract is available as Supplementary information.

TIMP-2 regulates 5-Fu resistance via the ERK/MAPK signaling pathway in colorectal cancer.

5-Fluorouracil (5-Fu) is the first-line chemotherapeutic option for colorectal cancer. However, its efficacy is inhibited by drug resistance. Cytokines play an important role in tumor drug resistance, even though their mechanisms are largely unknown. Using a cytokine array, we established that tissue inhibitor metalloproteinase 2 (TIMP-2) is highly expressed in 5-Fu resistant colorectal cancer patients. Analysis of samples from 84 patients showed that elevated TIMP-2 expression levels in colorectal patients were correlated with poor prognostic outcomes. In a 5-Fu-resistant patient-derived xenograft (PDX) model, TIMP-2 was also found to be highly expressed. We established an autocrine mechanism through which elevated TIMP-2 protein levels sustained colorectal cancer cell resistance to 5-Fu by constitutively activating the ERK/MAPK signaling pathway. Inhibition of TIMP-2 using an anti-TIMP-2 antibody or ERK/MAPK inhibition by U0126 suppressed TIMP-2 mediated 5-Fu-resistance in CRC patients. In conclusion, a novel TIMP-2-ERK/MAPK mediated 5-Fu resistance mechanism is involved in colorectal cancer. Therefore, targeting TIMP-2 or ERK/MAPK may provide a new strategy to overcome 5-Fu resistance in colorectal cancer chemotherapy.

Extracellular matrix alterations in the skin of patients affected by psoriasis

BackgroundPsoriasis is a chronic inflammatory disease dependent upon a complex interaction between genetic predisposition and immunological factors. It is characterized by skin lesions throughout the body, causing great morbidity and affecting life quality. The present study aimed to evaluate the protein and mRNA expression of heparanase-1 (HPSE), heparanase-2 (HPSE2), syndecan-1 (SYND1), metalloproteinases (MMP2, MMP9), and tissue inhibitor metalloproteinases 2 (TIMP2) in skin samples.MethodsFrom each psoriasis patient, two samples were collected, one sample from a psoriasis plaque (n = 23) and the other sample from non-affected skin (n = 23), as well as tissue collected by blepharoplasty from control individuals (n = 18). Protein expression was investigated by immunohistochemistry, followed by digital quantification. Quantitative RT-PCR obtained mRNA expression. Statistical analyses were done, and p values < 0.05 were considered significant.ResultsA significant increase in protein and mRNA expression was observed in both heparanases (HPSE and HPSE2), and higher protein levels of MMP9 and TIMP2 were observed in the psoriasis plaque compared to the non-affected skin. The data point to a probable activation of MMP2 by TIMP2. Moreover, there was a significant increase in HPSE2, SYND1, MMP9, and TIMP2 in non-affected skin samples from patients with psoriasis than in the control sample (tissue obtained by individuals who do not have psoriasis).ConclusionsThese results show a possible correlation between the characteristic inflammatory process and alterations in the expression of the extracellular matrix in psoriasis. The increased expression of HPSE2, SYND1, MMP9, and TIMP2, even in the absence of psoriatic plaque, indicates that these molecules may be involved with extracellular matrix changes in the initial alterations the psoriatic process and may be candidates for the development of target treatments.

Tissue inhibitor metalloproteinase 2 (TIMP-2) and insulin-like growth factor binding protein 7 (IGFBP7) best predicts the development of acute kidney injury

BackgroundAcute kidney injury (AKI) is routinely diagnosed by creatinine-based guidelines, which is sub-optimal marker after injury due to renal and non-renal factors. This has necessitated the need for more specific and sensitive biomarkers for early detection of AKI in at risk patients. This prospective cross-sectional study used the biomarkers of cell cycle arrest and Neutrophil Gelatinase Associated Lipocalin (NGAL) to assess AKI among hospitalized patients. MethodsWe conveniently enrolled 151 in-patients at the Trauma and Specialist Hospital, Winneba in Ghana. Socio-demographic and clinical information were collected using structured questionnaires. Blood samples were collected for the estimation of serum creatinine, and AKI diagnosed and staged using the KDIGO guideline. Fresh urine samples were collected and urinary NGAL, TIMP-2 (tissue inhibitor metalloproteinase 2) and IGFBP-7 (insulin-like growth factor binding protein 7) were estimated using ELISA kits. ResultsThe cell cycle arrest biomarkers and NGAL were significantly (P < 0.001) higher among participants with AKI than those without AKI. [TIMP-2]∗[IGFBP-7] showed the best diagnostic performance (AUC = 0.94, CI = 0.90–0.98) followed by [IGFBP-7]∗NGAL] (AUC = 0.93, CI = 0.87–0.99), with NGAL having the least (AUC = 0.62, CI = 0.46–0.78). The cut-off for [TIMP-2]∗[IGFBP-7] showed the best predictive ability (95.8% sensitivity, 77.2% specificity, 44.2% PPV and 99% NPV). The cut-off for NGAL, on the other hand, showed the least predictive ability (62.5% sensitivity, 42.5% specificity, 17.0% PPV and 85.7% NPV). ConclusionTissue inhibitor metalloproteinase 2 (TIMP-2) and insulin-like growth factor binding protein 7 (IGFBP7) best predicts the development of AKI, and can be used in high risk patients for early diagnosis of AKI.

The Association between Urinary Tissue Inhibitor Metalloproteinase 2 (TIMP-2) and Insulin-like Growth Factor Binding Protein 7 (IGFBP-7) and Renal Recovery in Acute Kidney Injury

Background. Acute kidney injury (AKI) is a common and serious medical condition associated with significant increases in morbidity, mortality, cost of care and non recovery of kidney function that leads to progression to chronic kidney disease. Cell cycle arrest is implicated in the pathogenesis and repair process following AKI. The urinary cell-cycle arrest markers tissue inhibitor of metalloproteinase-2 (TIMP-2) and insulin-like growth factor binding protein 7 (IGFBP-7) have been utilized to predict the risk of AKI in many studies from specific population with good performance. However, their use in predicting recovery is still lacking. The aim of this study was to determine the association between two novel AKI biomarkers, urinary TIMP2 and IGFBP7 and renal recovery after 7 days of treatment in AKI patients at Dr. Mohammad Hoesin Hospital Palembang.&#x0D; Method. This was a prospective cohort study conducted in dr. Mohammad Hoesin Hospital Palembang from January 2021 until March 2021. Subjects enrolled in this study were patients whom diagnosed AKI based on KDIGO 2012 criteria. Urine samples were collected upon patients’ enrollment within 24 hours of AKI diagnosis. We utilized Sandwich Enzyme Linked Immunosorbant Assay (ELISA) method to detect urinary TIMP-2 and IGFBP-7 levels. The primary outcome is recovery from AKI after 7 days of treatment. Chi square test is used to analyze the association between urinary TIMP-2 and IGFBP-7 levels and renal recovery.&#x0D; Results. There were 70 subjects, only 22 of them were recovered after 7 days (31%). Median of urinary TIMP-2 and IGFBP-7 was 0,0047(0,0001-0,1439) [(ng/ml)2/1000]. There was significant association between urinary TIMP2 and IGFBP7 and renal recovery (p=0,027; OR 3,19; 95% CI 1,116-9,128).&#x0D; Conclusion. There was significant association between urinary TIMP2 and IGFBP7 and renal recovery in AKI patients.

MO341VALUE OF THE CELL CYCLE ARREST BIOMARKERS IN THE DIAGNOSIS OF PREGNANCY RELATED ACUTE KIDNEY INURY

Abstract Background and Aims Pregnancy related acute kidney injury (PRAKI) is still a common serious problem in developing countries. Insulin-like growth factor-binding protein 7 (IGFBP7) and tissue inhibitor metalloproteinases-2 (TIMP-2) can identify critically ill patients at risk for the development of severe AKI. Aims: To identify main causes and timing of PRAKI and to study the G1 cell cycle arrest biomarkers in cases diagnosed with (PRAKI) as a diagnostic tool. Method 80 pregnant women diagnosed with PRAKI were recruited from a single hospital as well as 30 age-matched pregnant women with normal pregnancy participated in this study. A urine specimen was collected from all study participants with established AKI within 24 hours of ICU admission to measure [TIMP-2]*[IGFBP7]. Results The incidence of PRAKI was 1.1%. The most common cause of PRAKI is preeclampsia/eclampsia spectrum (61%). Most of the cases occur in the third trimester (60%) and postpartum period (23%). At a cutoff 0.33 ng/mL, the estimated sensitivity and specificity of urinary [TIMP-2]*[IGFBP7] in predicting PRAKI is 100% (95% CI) with NPV and PPV are 100%. Conclusion Urinary [TIMP-2]*[IGFBP7] serves as a sensitive and specific biomarker in the diagnosis of PRAKI.

Value of the cell cycle arrest biomarkers in the diagnosis of pregnancy-related acute kidney injury.

Background: Pregnancy-related acute kidney injury (PRAKI) is still a common serious problem in developing countries. Insulin-like growth factor-binding protein 7 (IGFBP7) and tissue inhibitor metalloproteinases-2 (TIMP-2) can identify critically ill patients at risk for the development of severe AKI. Aim: To identify main causes and timing of PRAKI and to study the G1 cell cycle arrest biomarkers in cases diagnosed with (PRAKI) as a diagnostic tool. Methods: 80 pregnant women diagnosed with PRAKI were recruited from a single hospital as well as 30 age-matched pregnant women with normal pregnancy participated in the present study. A urine specimen was collected from all study participants with established AKI within 24 h of ICU admission to measure [TIMP-2]*[IGFBP7]. Results: The incidence of PRAKI was 1.1%. The most common cause of PRAKI is pre-eclampsia/eclampsia spectrum (61%). Most of the cases occur in the third trimester (60%) and postpartum period (23%). At a cutoff 0.33 ng/ml, the estimated sensitivity and specificity of urinary [TIMP-2]*[IGFBP7] in predicting PRAKI is 100% (95% CI) with NPV and PPV are 100%. Conclusion: Urinary [TIMP-2]*[IGFBP7] serves as a sensitive and specific biomarker in the diagnosis of PRAKI.

Biomarker-Guided Risk Assessment for Acute Kidney Injury: Time for Clinical Implementation?

Acute kidney injury (AKI) is a common and serious complication in hospitalized patients, which continues to pose a clinical challenge for treating physicians. The most recent Kidney Disease Improving Global Outcomes practice guidelines for AKI have restated the importance of earliest possible detection of AKI and adjusting treatment accordingly. Since the emergence of initial studies examining the use of neutrophil gelatinase-associated lipocalin (NGAL) and cycle arrest biomarkers, tissue inhibitor metalloproteinase-2 (TIMP-2) and insulin-like growth factor-binding protein (IGFBP7), for early diagnosis of AKI, a vast number of studies have investigated the accuracy and additional clinical benefits of these biomarkers. As proposed by the Acute Dialysis Quality Initiative, new AKI diagnostic criteria should equally utilize glomerular function and tubular injury markers for AKI diagnosis. In addition to refining our capabilities in kidney risk prediction with kidney injury biomarkers, structural disorder phenotypes referred to as “preclinical-” and “subclinical AKI” have been described and are increasingly recognized. Additionally, positive biomarker test findings were found to provide prognostic information regardless of an acute decline in renal function (positive serum creatinine criteria). We summarize and discuss the recent findings focusing on two of the most promising and clinically available kidney injury biomarkers, NGAL and cell cycle arrest markers, in the context of AKI phenotypes. Finally, we draw conclusions regarding the clinical implications for kidney risk prediction.

Exosomes of adult human fibroblasts cultured on 3D silk fibroin nonwovens intensely stimulate neoangiogenesis.

Background Bombyx mori silk fibroin is a biomacromolecule that allows the assembly of scaffolds for tissue engineering and regeneration purposes due to its cellular adhesiveness, high biocompatibility and low immunogenicity. Earlier work showed that two types of 3D silk fibroin nonwovens (3D-SFnws) implanted into mouse subcutaneous tissue were promptly vascularized via undefined molecular mechanisms. The present study used nontumorigenic adult human dermal fibroblasts (HDFs) adhering to a third type of 3D-SFnws to assess whether HDFs release exosomes whose contents promote neoangiogenesis.MethodsElectron microscopy imaging and physical tests defined the features of the novel carded/hydroentangled 3D-SFnws. HDFs were cultured on 3D-SFnws and polystyrene plates in an exosome-depleted medium. DNA amounts and D-glucose consumption revealed the growth and metabolic activities of HDFs on 3D-SFnws. CD9-expressing total exosome fractions were from conditioned media of 3D-SFnws and 2D polystyrene plates HDF cultures. Angiogenic growth factors (AGFs) in equal amounts of the two groups of exosomal proteins were analysed via double-antibody arrays. A tube formation assay using human dermal microvascular endothelial cells (HDMVECs) was used to evaluate the exosomes’ angiogenic power.ResultsThe novel features of the 3D-SFnws met the biomechanical requirements typical of human soft tissues. By experimental day 15, 3D-SFnws-adhering HDFs had increased 4.5-fold in numbers and metabolized 5.4-fold more D-glucose than at day 3 in vitro. Compared to polystyrene-stuck HDFs, exosomes from 3D-SFnws-adhering HDFs carried significantly higher amounts of AGFs, such as interleukin (IL)-1α, IL-4 and IL-8; angiopoietin-1 and angiopoietin-2; angiopoietin-1 receptor (or Tie-2); growth-regulated oncogene (GRO)-α, GRO-β and GRO-γ; matrix metalloproteinase-1; tissue inhibitor metalloproteinase-1; and urokinase-type plasminogen activator surface receptor, but lesser amounts of anti-angiogenic tissue inhibitor metalloproteinase-2 and pro-inflammatory monocyte chemoattractant protein-1. At concentrations from 0.62 to 10 μg/ml, the exosomes from 3D-SFnws-cultured HDFs proved their angiogenic power by inducing HDMVECs to form significant amounts of tubes in vitro.ConclusionsThe structural and mechanical properties of carded/hydroentangled 3D-SFnws proved their suitability for tissue engineering and regeneration applications. Consistent with our hypothesis, 3D-SFnws-adhering HDFs released exosomes carrying several AGFs that induced HDMVECs to promptly assemble vascular tubes in vitro. Hence, we posit that once implanted in vivo, the 3D-SFnws/HDFs interactions could promote the vascularization and repair of extended skin wounds due to burns or other noxious agents in human and veterinary clinical settings.

Effects of Curcumin Against Matrix Metalloproteinase-2 (MMP-2) and Tissue Inhibitor Metalloproteinase-2 (TIMP-2) Serum Level on Rat Model of Liver Fibrosis Resolution Process

Background: Liver fibrosis is an effect from continuous fibrogenesis and fibrolysis process. During fibrogenesis, MMP-2 and TIMP-2 that produced by hepatic stellate cell (HSC) have a role to regulate extracellular matrix (ECM) homeostastic. Otherwise, curcumin inhibits both MMP-2 and TIMP-2 expression and enhances HSC apoptosis, thus inhibit fibrogenesis. Role of curcumin, MMP-2, and TIMP-2 in a fibrolysis process has not been widely studied. This study aimed to determine the correlation between curcumin administration and the decline of MMP-2 and TIMP-2 on rat model of liver fibrosis.Method: This is an experimental study done in male Wistar rats. There are 8 groups consist of 4 rats each. Both control and intervention group were exposed to CCl4 1 cc/kgBW intraperitoneally 2 times per week for 9 consecutive weeks to form F3 fibrosis. Negative control group was injected with normal saline. After CCl4 injection, control group was given curcumin solvent as placebo while intervention groups were given curcumin 200 mg/kgBW for 2, 5, and 9 weeks. Statistical analysis then conducted in the end of study. Results: MMP-2 and TIMP-2 were remarkably increased in positive control group, but found decreased in control group 5 and 9. There are remarkable decrease of MMP-2 and TIMP-2 serum level in intervention group 2, 5, and 9, but MMP-2 and TIMP-2 level was significantly lower in intervention group 2 compared to the control group.Conclusion: MMP-2 and TIMP-2 serum level were decreased after giving of curcumin for 2 weeks. The duration of curcumin administration correlated with decrease of TIMP-2 serum level but not correlated with MMP-2 serum level in rat model of liver fibrosis.

The Biomarker TCONS_00016233 Drives Septic AKI by Targeting the miR-22-3p/AIFM1 Signaling Axis

The prediction of mortality for septic acute kidney injury (AKI) has been assessed by a number of potential biomarkers, including long noncoding RNAs (lncRNAs). However, the validation of lncRNAs as biomarkers, particularly for the early stages of septic AKI, is still warranted. Our results indicate that the lncRNA TCONS_00016233 is upregulated in plasma of sepsis-associated non-AKI and AKI patients, but a higher cutoff threshold (9.5 × 105, copy number) provided a sensitivity of 71.9% and specificity of 89.6% for the detection of AKI. The plasma TCONS_00016233 was highly correlated with serum creatinine, tissue inhibitor metalloproteinase-2 (TIMP-2), insulin-like growth factor binding protein-7 (IGFBP7), interleukin-1β (IL-1β), tumor necrosis factor α (TNF-α), C-reactive protein (CRP), and urinary TCONS_00016233. Lipopolysaccharide (LPS) induced the expression of lncRNA TCONS_00016233 via the Toll-like receptor 4 (TLR4)/p38 mitogen-activated protein kinase (MAPK) signal pathway in human renal tubular epithelial (HK-2) cells. Furthermore, TCONS_00016233 mediates the LPS-induced HK-2 cell apoptosis and the expression of IL-1β and TNF-α. Mechanistically, TCONS_00016233 acts as a competing endogenous RNA (ceRNA) to prevent microRNA (miR)-22-3p-mediated downregulation of the apoptosis-inducing factor mitochondrion-associated 1 (AIFM1). Finally, overexpression of TCONS_00016233 is capable of aggravating the LPS- and cecal ligation and puncture (CLP)-induced septic AKI by targeting the miR-22-3p/AIFM1 axis. Taken together, our data indicate that TCONS_00016233 may serve as an early diagnosis marker for the septic AKI, possibly acting as a novel therapeutic target for septic AKI.

Potential Prognostic Markers of Acute Kidney Injury in the Early Phase of Acute Pancreatitis.

Acute kidney injury (AKI) is a serious complication of acute pancreatitis (AP), which occurs in up to 70% of patients with severe AP and significantly increases the risk of mortality. At present, AKI is diagnosed based on dynamic increase in serum creatinine and decreased urine output; however, there is a need for earlier and more accurate biomarkers. The aim of the study was to review current evidence on the laboratory tests that were studied as the potential biomarkers of AKI in AP. We also briefly summarized the knowledge coming from the studies including sepsis or ICU patients since severe acute pancreatitis is associated with systemic inflammation and organ failure. Serum cystatin C and serum or urine NGAL have been shown to predict or diagnose AKI in AP; however, this evidence come from the single center studies of low number of patients. Other markers, such as urinary kidney injury molecule-1, cell cycle arrest biomarkers (tissue inhibitor metalloproteinase-2 and urine insulin-like growth factor-binding protein 7), interleukin-18, liver-type fatty acid-binding protein, or calprotectin have been studied in other populations suffering from systemic inflammatory states. In AP, the potential markers of AKI may be significantly influenced by either dehydration or inflammation, and the impact of these factors may be difficult to distinguish from kidney injury. The subject of AKI complicating AP is understudied. More studies are needed, for both exploratory (to choose the best markers) and clinical (to evaluate the diagnostic accuracy of the chosen markers in real clinical settings).

Tissue inhibitor metalloproteinase-2 (TIMP-2) • IGF-binding protein-7 (IGFBP7) levels are associated with adverse outcomes in patients in the intensive care unit with acute kidney injury

The G1 cell cycle inhibitors tissue inhibitor metalloproteinase-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7) have been identified as novel biomarkers for the prediction of moderate to severe acute kidney injury (AKI) risk. However, the prognostic value of [TIMP-2]•[IGFBP7] in predicting adverse outcomes in intensive care unit (ICU) patients with AKI was not previously described. To evaluate this, we conducted a cohort study, measuring [TIMP2]•[IGFBP7] levels in critically ill patients admitted to the ICU and classified the patients as NephroCheck (NC) (+) or NC (-) according to [TIMP-2]•[IGFBP7] values and AKI (+) or AKI (-) according to Kidney Disease: Improving Global Outcomes (KDIGO) criteria. We then evaluated the incidence of continuous renal replacement therapy initiation, all-cause mortality and a composite endpoint of both in the four groups. Baseline [TIMP-2]•[IGFBP7] values were available for 719 patients, of whom 239 developed AKI and 151 met the composite endpoint. Compared to NC (-)/AKI (+) patients, NC (+)/AKI (+) patients had a significant risk of ICU mortality and the composite endpoint. Kaplan-Meier curves showed that the survival estimate for the composite endpoint of NC (+)/AKI (+) patients was 34.4%; significantly worse than NC (-)/AKI (+) patients (67.4%). Multivariate analyses showed strong association between NC positivity and the composite endpoint. The inflammatory marker, procalcitonin, was an additional prognostic biomarker to compare and confirm the incremental value of NephroCheck. No association between procalcitonin and the composite endpoint was found, especially in patients with AKI, suggesting that NephroCheck may be more kidney specific. Thus, the [TIMP-2]•[IGFBP7] values can serve to identify patients with AKI at increased risk for adverse outcomes in the ICU.