[Exploring the mechanism of IgA vasculitis pathogenesis through the interaction of thrombin and inflammatory factors using urinary proteomics]. / è¿ç”¨å°¿è›‹ç™½ç»„å­¦æŠ€æœ¯æŽ¢ç´¢å‡è¡€é ¶ä¸Žç‚Žç—‡å› å­ç›¸äº’ä½œç”¨å‚ä¸ŽIgAè¡€ç®¡ç‚Žå‘ç— çš„æœºåˆ¶.

OBJECTIVES: To explore the evidence, urinary biomarkers, and partial mechanisms of hypercoagulability in the pathogenesis of IgA vasculitis (IgAV). METHODS: Differential expression of proteins in the urine of 10 healthy children and 10 children with IgAV was screened using high-performance liquid chromatography-tandem mass spectrometry, followed by Reactome pathway analysis. Protein-protein interaction (PPI) network analysis was conducted using STRING and Cytoscape software. In the validation cohort, 15 healthy children and 25 children with IgAV were included, and the expression levels of differential urinary proteins were verified using enzyme-linked immunosorbent assay. RESULTS: A total of 772 differential proteins were identified between the IgAV group and the control group, with 768 upregulated and 4 downregulated. Reactome pathway enrichment results showed that neutrophil degranulation, platelet activation, and hemostasis pathways were involved in the pathogenesis of IgAV. Among the differential proteins, macrophage migration inhibitory factor (MIF) played a significant role in neutrophil degranulation and hemostasis, while thrombin was a key protein in platelet activation and hemostasis pathways. PPI analysis indicated that thrombin directly interacted with several proteins involved in inflammatory responses, and these interactions involved MIF. Validation results showed that compared to healthy children, children with IgAV had significantly higher urine thrombin/creatinine and urine MIF/creatinine levels (P<0.05). CONCLUSIONS: Thrombin contributes to the pathogenesis of IgAV through interactions with inflammatory factors. Urinary thrombin and MIF can serve as biomarkers reflecting the hypercoagulable and inflammatory states in children with IgAV.

Urinary matrix metalloproteinase-7 is a sensitive biomarker to evaluate renal tubular injury in patients with minimal change disease and focal segmental glomerulosclerosis.

Objective: To explore the advantages of urinary matrix metalloproteinase-7 (MMP-7) in evaluating renal tubular injury in minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS) patients compared with urinary cystatin C (CysC) and retinol-binding protein (RBP). Methods: Serum and urine samples were collected from 20 healthy volunteers, and 40 MCD and 20 FSGS patients. Serum and urinary MMP-7 levels were measured by enzyme-linked immunosorbent assay. Urinary total protein, CysC and RBP levels were measured by automatic specific protein analyzer and compared with urinary creatinine level for calibration. The renal tissue serial sections were stained by MMP-7 immunohistochemistry and periodic acid-Schiff. Results: Under light microscopy, MMP-7 granular weak positive expression was showed sporadically in the cytoplasm of a few renal tubular epithelial cells without obvious morphological changes in MCD patients, and MMP-7-positive expression was observed in the cytoplasm of some renal tubular epithelial cells in FSGS patients. There was no significant difference in serum MMP-7 level among the three groups. Compared with the control group, the urinary MMP-7 level in MCD patients was higher, but urinary CysC and RBP levels were not increased significantly. Compared with the control group and MCD patients, urinary MMP-7, CysC and RBP levels in FSGS patients were upregulated significantly. Conclusions: Urinary MMP-7 could not only evaluate the mild renal tubular epithelial cells injury in MCD patients with massive proteinuria, but also evaluate the continuous renal tubular epithelial cells injury in FSGS patients.

Novel therapeutic perspectives for crescentic glomerulonephritis through targeting parietal epithelial cell activation and proliferation.

INTRODUCTION: Kidney injury is clinically classified as crescentic glomerulonephritis (CrGN) when ≥50% of the glomeruli in a biopsy sample contain crescentic lesions. However, current strategies, such as systemic immunosuppressive therapy and plasmapheresis for CrGN, are partially effective, and these drugs have considerable systemic side effects. Hence, targeted therapy to prevent glomerular crescent formation and expansion remains an unmet clinical need. AREAS COVERED: Hyperproliferative parietal epithelial cells (PECs) are the main constituent cells of the glomerular crescent with cell-tracing evidence. Crescents obstruct the flow of primary urine, pressure the capillaries, and degenerate the affected nephrons. We reviewed the markers of PEC activation and proliferation, potential therapeutic effects of thrombin and thrombin receptor inhibitors, and how podocytes cross-talk with PECs. These experiments may help identify potential early specific targets for the prevention and treatment of glomerular crescentic injury. EXPERT OPINION: Inhibiting PEC activation and proliferation in CrGN can alleviate glomerular crescent progression, which has been supported by preclinical studies with evidence of genetic deletion. Clarifying the outcome of PEC transformation to the podocyte phenotype and suppressing thrombin, thrombin receptors, and PEC hyperproliferation in early therapeutic strategies will be the research goals in the next ten years.

It is clinically classified as crescentic glomerulonephritis (CrGN) when more than 50% of the glomeruli of the kidney in a biopsy sample contain crescentic lesions (crescent shaped injuries). However, current strategies, such as immunosuppressive therapy and plasmapheresis (the removal, treatment and returning of blood) for CrGN, are partially effective, and these drugs have considerable side effects. In order to seek targeted therapy for CrGN, we reviewed the current research evidences. First, the hyperproliferative parietal epithelial cells (PECs) are the main cells within the glomerular crescent seen with cell-tracing evidence. The activated PECs can express specific markers and altered biological characteristics, such as cell growth and multiplication, migration, and extracellular matrix production. CD44, CD74, CD9, and pERK-1/2 are specific markers for PEC activation, and also as the potential therapeutic targets with evidence of gene knockout and inhibitor. Second, during the formation of glomerular crescents, PECs grow and multiply also through cross-talking with podocyte cells by the AngII/SDF-1/CXCR4/ERK1/2, HB-EGF/EGFR/JAK/STAT3, and PDGF/PDGFR signaling pathways, suggesting that the intervention of key molecules in these disease processes may be promising therapeutic targets for CrGN. Third, thrombin and protease-activated receptors (PARs) participate in the excessive proliferation of PEC through activation of the coagulation cascade reaction, PAR-1 and PAR-2. Therefore, anticoagulation therapy, especially inhibition of PAR-1 and PAR-2, is expected to be an effective strategy for the early prevention and treatment of CrGN. The drug vorapaxar selectively antagonizes PAR-1 and is the most promising candidate. These findings will not only improve the outlook for CrGN treatment, but will also help in the treatment of other glomerular diseases with crescentic lesions. [Figure: see text].

Annexin A2: The diversity of pathological effects in tumorigenesis and immune response.

Annexin A2 (ANXA2) is widely used as a marker in a variety of tumors. By regulating multiple signal pathways, ANXA2 promotes the epithelial-mesenchymal transition, which can cause tumorigenesis and accelerate thymus degeneration. The elevated ANXA2 heterotetramer facilitates the production of plasmin, which participates in pathophysiologic processes such as tumor cell invasion and metastasis, bleeding diseases, angiogenesis, inducing the expression of inflammatory factors. In addition, the ANXA2 on the cell membrane mediates immune response via its interaction with surface proteins of pathogens, C1q, toll-like receptor 2, anti-dsDNA antibodies and immunoglobulins. Nuclear ANXA2 plays a role as part of a primer recognition protein complex that enhances DNA synthesis and cells proliferation by acting on the G1-S phase of the cell. ANXA2 reduction leads to the inhibition of invasion and metastasis in multiple tumor cells, bleeding complications in acute promyelocytic leukemia, retinal angiogenesis, autoimmunity response and tumor drug resistance. In this review, we provide an update on the pathological effects of ANXA2 in both tumorigenesis and the immune response. We highlight ANXA2 as a critical protein in numerous malignancies and the immune host response.

Pirfenidone Attenuates Renal Tubulointerstitial Fibrosis through Inhibiting miR-21.

BACKGROUND: Our previous studies had shown pirfenidone (PFD) not only improved tubulointerstitial fibrosis (TIF) but also inhibited the expression of microRNA-21 (miR-21) in the renal tissue of unilateral urethral obstruction (UUO) rats. This study aims to investigate whether PFD can attenuate TIF through inhibiting miR-21 in UUO rats. METHODS: Sprague Dawley rats were divided randomly into sham-operated group, UUO group, and PFD and olmesartan (Olm) treatment groups. Samples were collected on day 14. Expression of miR-21, TGF-ß1, Smad3, and Smad7 mRNA in the renal tissue was detected using real-time quantitative PCR. Immunohistochemistry was performed to assess the protein expressions of collagen III, E-cadherin, and α-SMA. Automated capillary Western blotting was used to detect the quantitative expression of TGF-ß1, Smad3, p-Smad3, Smad7, collagen III, E-cadherin, and α-SMA in renal tissues. The expression of miR-21 and Smad7 mRNA and the protein levels of collagen III and α-SMA were examined in the miR-21-overexpressing cell line, NRK-52E. RESULTS: Compared with the UUO group, both PFD and Olm inhibited renal tubular dilation, diffused epithelial cell degeneration and necrosis, and reduced renal interstitial edema, inflammatory cell infiltration, and collagen fiber deposition, while no significant difference between PFD group and Olm group. Informatics-based approaches identified Smad7 as a likely candidate for regulation by miR-21. Compared with the sham group, miR-21 expression was upregulated in the UUO group resulting in the downregulation of Smad7 expression due to degradation. The overexpression of miR-21 in the in vitro model downregulated Smad7 and promoted EMT and ECM accumulation. Protein levels of TGF-ß1, Smad3, p-Smad3, collagen III, and α-SMA were upregulated, while E-cadherin protein was downregulated in the UUO group than in the sham group. PFD rather than Olm decreased the expression of miR-21 and increased the expression level of Smad7 mRNA and then inhibited the TGF-ß1/Smad3 signaling pathway. Olm only downregulated the TGF-ß1/Smad3 signaling pathway. CONCLUSIONS: PFD improves TIF by downregulating the expression of miR-21, then elevating Smad7, and finally inhibiting the activation of the TGF-ß1/Smad3 signaling pathway in UUO rats.

Upregulation of STK15 in esophageal squamous cell carcinomas in a Mongolian population.

BACKGROUND: The STK15 gene located on chromosome 20q13.2 encodes a centrosome-associated kinase critical for regulated chromosome segregation and cytokinesis. Recent studies have demonstrated STK15 to be significantly associated with many tumors, with aberrant expression obseved in many human malignancies. The purpose of this study was to investigate expression of STK15 in esophageal squamous cell carcinomas (ESCCs) in a Mongolian population. METHODS: Two non-synonymous single nucleotide polymorphisms in the coding region of STK15, rs2273535 (Phe31Ile) and rs1047972 (Val57Ile) were assessed in 380 ESCC patients and 380 healthy controls. We also detected STK15 mRNA expression in 39 esophageal squamous cell carcinomas and corresponding adjacent tissues by real time PCR. RESULTS: rs2273535 showed a significant association with ESCC in our Mongolian population (rs227353, P allele=0.0447, OR (95%CI)=1.259 (1.005~1.578)). Real time PCR analysis of ESCC tissues showed that expression of STK15 mRNA in cancer tissues was higher than in normal tissues (p=0.013). CONCLUSIONS: Our study showed that functional SNPs in the STK15 gene are associated with ESCC in a Mongolian population and up-regulation of STK15 mRNAoccurs in ESCC tumors compared adjacent normal tissues. STK15 may thus have an important role in the prognosis of ESCC and be a potential therapeutic target.