HNF1B-related disease is an emerging condition characterized by an autosomal-dominant inheritance, a 50% rate of de novo mutations, and a highly variable phenotype (renal involvement, maturity-onset ...diabetes of the young type 5, pancreatic hypoplasia, and urogenital tract and liver test abnormalities). Given the current lack of pathognomonic characteristics and the wide overlap with other conditions, a genetic test is the diagnostic gold standard. However, pre-genetic screening is mandatory because genetic testing has substantial costs. Our aim was to develop a HNF1B score, based on clinical, imaging, and biological variables, as a pivotal tool for rational genetic testing. A score was created using a weighted combination of the most discriminative characteristics based on the frequency and specificity in published series. The HNF1B score is calculated upon 17 items including antenatal discovery, family history, and organ involvement (kidney, pancreas, liver, and genital tract). The performance of the score was assessed by a ROC curve analysis in a 433-individual cohort containing 56 HNF1B cases. The HNF1B score efficiently and significantly discriminated between mutated and nonmutated cases (AUC 0.78). The optimal cutoff threshold for the negative predictive value to rule out HNF1B mutations in a suspected individual was 8 (sensitivity 98.2%, specificity 41.1%, and negative predictive value over 99%). Thus, the HNF1B score is a simple and accurate tool to provide a more rational approach to select patients for HNF1B screening.
Recent studies suggested that ibrutinib, a Bruton tyrosine kinase (BTK) inhibitor, developed for the treatment of chronic lymphocytic leukemia, may prevent NLRP3 inflammasome activation in ...macrophages, IL-1β secretion and subsequent development of inflammation and organ fibrosis. The role of NLRP3 has been underlined in the various causes of acute kidney injury (AKI), a pathology characterized by high morbimortality and risk of transition toward chronic kidney disease (CKD). We therefore hypothesized that the BTK-inhibitor ibrutinib could be a candidate drug for AKI treatment. Here, we observed in both an AKI model (glycerol-induced rhabdomyolysis) and a model of rapidly progressive kidney fibrosis (unilateral ureteral obstruction), that ibrutinib did not prevent inflammatory cell recruitment in the kidney and fibrosis. Moreover, ibrutinib pre-exposure led to high mortality rate owing to severer rhabdomyolysis and AKI. In vitro, ibrutinib potentiated or had no effect on the secretion of IL-1β by monocytes exposed to uromodulin or myoglobin, two danger-associated molecule patterns proteins involved in the AKI to CKD transition. According to these results, ibrutinib should not be considered a candidate drug for patients developing AKI.
Rhabdomyolysis is a risk factor for acute kidney injury, transition towards chronic kidney disease, and death. The role of calcium phosphate deposits in the mechanisms of rhabdomyolysis-induced acute ...kidney injury (RAKI) is still unclear. Better insight of the role calcium in RAKI could lead to new therapeutic avenues. Here, we show in a mice model of RAKI that calcium phosphate deposits were frequent in the kidney (hydroxyapatite) and partly correlated with the severity of the kidney injury. However, the intensity of deposits was highly heterogeneous between mice. Treatment with sodium chloride, sodium bicarbonate or inorganic pyrophosphate (PPi; an inhibitor of the calcium phosphate crystallization), or combinations thereof, did not improve kidney outcomes and hydroxyapatite deposition during RAKI. Unexpectedly, Abcc6 knockout mice (ko), characterized by PPi deficiency, developed less severe RAKI despite similar rhabdomyolysis severity, and had similar hydroxyapatite deposition suggesting alternative mechanisms. This improved kidney outcome at day 2 translated to a trend in improved glomerular filtration rate at month 2 in Abcc6
mice and to significantly less interstitial fibrosis. In addition, whereas the pattern of infiltrating cells at day 2 was similar between wt and ko mice, kidneys of Abcc6
mice were characterized by more CD19
B-cells, less CD3
T-cells and a lower R1/R2 macrophage ratio at month 2. In summary, kidney calcium phosphate deposits are frequent in RAKI but hydration with sodium bicarbonate or sodium chloride does not modify the kidney outcome. Blocking ABCC6 emerges as a new option to prevent RAKI and subsequent transition toward kidney fibrosis.
The delayed diagnosis of acute kidney injury (AKI) episodes and the lack of specificity of current single AKI biomarkers hamper its management. Urinary peptidome analysis may help to identify early ...molecular changes in AKI and grasp its complexity to identify potential targetable molecular pathways.
In derivation and validation cohorts totalizing 1170 major cardiac bypass surgery patients and in an external cohort of 1569 intensive care unit (ICU) patients, a peptide-based score predictive of AKI (7-day KDIGO classification) was developed, validated, and compared to the reference biomarker urinary NGAL and NephroCheck and clinical scores.
A set of 204 urinary peptides derived from 48 proteins related to hemolysis, inflammation, immune cells trafficking, innate immunity, and cell growth and survival was identified and validated for the early discrimination (< 4 h) of patients according to their risk to develop AKI (OR 6.13 3.96-9.59, p < 0.001) outperforming reference biomarkers (urinary NGAL and IGFBP7.TIMP2 product) and clinical scores. In an external cohort of 1569 ICU patients, performances of the signature were similar (OR 5.92 4.73-7.45, p < 0.001), and it was also associated with the in-hospital mortality (OR 2.62 2.05-3.38, p < 0.001).
An overarching AKI physiopathology-driven urinary peptide signature shows significant promise for identifying, at an early stage, patients who will progress to AKI and thus to develop tailored treatments for this frequent and life-threatening condition. Performance of the urine peptide signature is as high as or higher than that of single biomarkers but adds mechanistic information that may help to discriminate sub-phenotypes of AKI offering new therapeutic avenues.
Tubular epithelial cells in the kidney are continuously exposed to urinary fluid shear stress (FSS) generated by urine movement and recent in vitro studies suggest that changes of FSS could ...contribute to kidney injury. However it is unclear whether FSS alters the epithelial characteristics of the renal tubule. Here, we evaluated in vitro and in vivo the influence of FSS on epithelial characteristics of renal proximal tubular cells taking the organization of junctional complexes and the presence of the primary cilium as markers of epithelial phenotype. Human tubular cells (HK-2) were subjected to FSS (0.5 Pa) for 48 h. Control cells were maintained under static conditions. Markers of tight junctions (Claudin-2, ZO-1), Par polarity complex (Pard6), adherens junctions (E-Cadherin, β-Catenin) and the primary cilium (α-acetylated Tubulin) were analysed by quantitative PCR, Western blot or immunocytochemistry. In response to FSS, Claudin-2 disappeared and ZO-1 displayed punctuated and discontinuous staining in the plasma membrane. Expression of Pard6 was also decreased. Moreover, E-Cadherin abundance was decreased, while its major repressors Snail1 and Snail2 were overexpressed, and β-Catenin staining was disrupted along the cell periphery. Finally, FSS subjected-cells exhibited disappeared primary cilium. Results were confirmed in vivo in a uninephrectomy (8 months) mouse model where increased FSS induced by adaptive hyperfiltration in remnant kidney was accompanied by both decreased epithelial gene expression including ZO-1, E-cadherin and β-Catenin and disappearance of tubular cilia. In conclusion, these results show that proximal tubular cells lose an important number of their epithelial characteristics after long term exposure to FSS both in vitro and in vivo. Thus, the changes in urinary FSS associated with nephropathies should be considered as potential insults for tubular cells leading to disorganization of the tubular epithelium.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In early human pregnancy, uterine decidual NK cells (dNK) are abundant and considered as cytokine producers but poorly cytotoxic despite their cytolytic granule content, suggesting a negative control ...of this latter effector function. To investigate the basis of this control, we examined the relative contribution to the cytotoxic function of different activating receptors expressed by dNK. Using a multicolor flow cytometry analysis, we found that freshly isolated dNK exhibit a unique repertoire of activating and inhibitory receptors, identical among all the donors tested. We then demonstrated that in fresh dNK, mAb-specific engagement of NKp46-, and to a lesser extent NKG2C-, but not NKp30-activating receptors induced intracellular calcium mobilization, perforin polarization, granule exocytosis and efficient target cell lysis. NKp46-mediated cytotoxicity is coactivated by CD2 but dramatically blocked by NKG2A coengagement, indicating that the dNK cytotoxic potential could be tightly controlled in vivo. We finally found that in dNK, mAb-specific engagement of NKp30, but not NKp46, triggered the production of IFN-gamma, TNF-alpha, MIP-1alpha, MIP-1beta, and GM-CSF proinflammatory molecules. These data demonstrate a differential, controlled role of NKp46- and NKp30-activating receptors expressed by dNK that could be critical for the outcome of pregnancy and the killing of uterine cells infected by pathogens.
Septic shock is the most common cause of acute kidney injury (AKI), but the underlying mechanisms remain unclear and no targeted therapies exist. Lysophosphatidic acid (LPA) is a bioactive lipid ...which
in vivo
administration was reported to mitigate inflammation and injuries caused by bacterial endotoxemia in the liver and lung. The objective of the present study was to determine whether LPA can protect against sepsis-associated AKI. C57BL/6 mice were treated with LPA 18:1 (5 mg/kg, i.p.) 1 h before being injected with the endotoxin lipopolysaccharide (LPS), and AKI was evaluated after 24 h. LPA significantly decreased the elevation of plasma urea and creatinine caused by LPS. In the kidney, LPA pretreatment significantly reduced the upregulation of inflammatory cytokines (IL-6, TNFα, monocyte chemoattractant protein-1 (MCP-1)), and completely prevented downregulation of peroxisome proliferator-activated receptor gamma coactivator 1-alpha and upregulation of heme oxygenase-1 caused by LPS. LPA also prevented LPS-mediated alterations of the renal mitochondrial ultrastructure.
In vitro
pretreatment with LPA 18:1 significantly attenuated LPS-induced upregulation of the inflammatory cytokines (TNFα and MCP-1) in RAW264 macrophages. Moreover,
in vivo
LPS treatment lowered urinary LPA concentration and reduced LPA anabolic enzymes (autotaxin and acylglycerol kinase), and increased the LPA catalytic enzyme (lipid phosphate phosphatase 2) expression in the kidney cortex. In conclusion, exogenous LPA exerted a protective action against renal inflammation and injuries caused by bacterial endotoxemia. Moreover, LPS reduces the renal production of LPA suggesting that sepsis-associated AKI could be mediated, at least in part, by alleviation of the protective action of endogenous LPA.
Background
Renal complications of non-Hodgkin lymphoma encompass a wide spectrum of monoclonal Ig-related pathologies. Clonal circulating T cells can also be associated with non-renal autoimmune ...disorders induced by overproduction of specific patterns of cytokines or unbalanced lymphocytes sub-populations.
Methods
Immunophenotyping of circulating T cells and TCR gene restriction analysis using Biomed-2 protocol. NF-κB staining and mRNA quantification of inflammatory genes in HK-2 epithelial renal cells exposed to supernatants of peripheral blood mononuclear cells with clonal T-cell population.
Results
Here, we could identify a persistent clonal T-cell population, only characterized by in-depth immunophenotyping of circulating lymphocytes and using multiplex PCR analysis of TCR gene rearrangements, in two patients with polymorphic inflammatory renal fibrosis of unknown origin. Using an in vitro approach, we could demonstrate that peripheral blood mononuclear cells including the clonal population can trigger a phenotype switch of epithelial renal cells from a quiescent state to a pro-inflammatory state characterized by NF-κB nuclear translocation and overexpression of inflammatory cytokine or chemokine.
Conclusion
These preliminary data suggest that circulating T-cell clones may directly activate epithelial renal cells or promote a T-/B-cell population with autoimmune reactive properties against kidney cells, which, in the absence of overt renal lymphoma infiltration, lead to the subsequent inflammatory renal fibrotic phenotype.
Abstract Introduction The optimal regional anticoagulation (RA) of dialysis filters in patients at risk of bleeding remains elusive. Inducing hypocalcemia within the filter by using a calcium-free ...dialysate has emerged as an easy-to-use heparin-free RA, including in critically ill patients, but comparative studies are lacking. Methods We conducted a multicentre, randomized, crossover trial to compare the efficacy and tolerance of two RAs (heparin-coated membrane (HCM) or calcium free dialysate with calcium reinjection according to ionic dialysance (CFD)) in patients requiring hemodialysis and at risk of bleeding. During the study period, each patient received two dialysis sessions (one with each RA in a randomly assigned order). The primary endpoint was the proportion of dialysis sessions completed (≥ 240 min). Results 94 patients were included in the intention-to-treat analysis, including 16 critically ill patients (17.0%). Coagulation and inflammation parameters, as well as hemodynamic status at baseline, were balanced between groups. Premature coagulation of the filter occurred in 19 HCM (20.9%) compared to 3 (3.2%) CFD sessions. In half of the sessions with premature termination, coagulation occurred before 180 minutes. The proportion of patients who completed the CFD session while failing to complete the HCM session (n = 17) was significantly higher than the proportion of patients who completed the HCM session while failing to complete the CFD session (n = 1; p < 0.001). Hemodynamic and metabolic tolerance were not different between groups. Conclusions In individuals at risk of bleeding, RA with calcium-free dialysate significantly reduces the incidence of premature dialysis termination compared to heparin-coated membrane without safety concerns. Trial registration and statistical analysis plan: ClinicalTrials.gov identifier: NCT03842657.
Abstract Background and Aims Vascular calcification, defined as the abnormal deposition of minerals in blood vessels, is a major cardiovascular risk factor in patients with kidney failure. ...Sodium-glucose co-transporter 2 (SGLT2) inhibitors, commonly known as gliflozins, are a class of pharmaceutical compounds that have revolutionised the therapeutic management of type 2 diabetes. These drugs target the SGLT2 transporter, increasing glucose elimination through the urine, effectively lowering hyperglycaemia. In addition to their effect on blood sugar control, SGLT2 inhibitors have recently gained attention for potential cardiovascular benefits in patients with type 2 diabetes, chronic kidney disease (CKD) or established cardiovascular disease. Initially thought to be secondary to the promotion of urinary sodium and glucose excretion and weight loss, recent studies have also reported direct effects of gliflozins on the vascular compartment. Given the significant impact of vascular calcification on cardiovascular health in patients with kidney failure, the aim of this study was to investigate whether the three different SGLT2 inhibitors (canagliflozin, empagliflozin and dapagliflozin) could reduce the development of vascular calcification. Method Western blotting was used to investigate SGLT2 expression in mouse and human vascular smooth muscle cells (VSMC) and vascular explants. Human and mouse aortic VSMC and mouse aorta and human epigastric and iliac artery segments were treated with calcification medium supplemented with 1 or 5 µM of gliflozins. A nephrocalcinosis mouse model consisting of 2 weeks of high phosphorus diet (2%) in female DBA/2 mice was used in in vivo experiments. The animals were treated daily with the different gliflozins (3 mg/kg/j) by oral gavage. Calcium deposits were quantified using a quantitative colorimetric assay and alizarin red staining, blood and urine glucose levels were measured using a quantitative colorimetric assay and glomerular filtration rate (GFR) was measured using sinistrin-FITC excretion. Results We observed that SGLT2 is expressed in mouse and human vessels and vascular smooth muscle cells (VSMC). Treatment with canagliflozin, but not dapagliflozin or empagliflozin, reduced calcification in vitro, in human and mouse VSMC and ex vivo, in mouse aorta and human epigastric and iliac artery segments. The high phosphorus diet in mice led to nephrocalcinosis associated with impaired renal function as well as vascular calcification development in the aorta. In this model, although all 3 gliflozins showed efficacy in increasing urinary glucose excretion, blood glucose levels were not affected by gliflozins and renal function was not improved. However, canagliflozin, but not dapagliflozin or empagliflozin, significantly reduced vascular calcification in this nephrocalcinosis mouse model. Conclusion Our study demonstrated that canagliflozin reduces vascular calcification development, highlighting its potential as a therapeutic strategy. This protective effect was found to be drug-dependent and not class-dependent, as the other two SGLT2 inhibitors, dapagliflozin and empagliflozin, showed no significant effect on vascular calcification. Further studies are needed to understand the mechanisms and pathways involved and to determine whether the differential effect of the gliflozins is due to an off-target action of canagliflozin on other SGLT transporters.
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