A temporally-restricted pattern of endothelial cell collagen 4 alpha 1 expression during embryonic development determined with a novel knockin Col4a1-P2A-eGFP mouse line.

Classical collagen type IV comprising of a heterotrimer of two collagen IV alpha 1 chains and one collagen IV alpha 2 chain is the principal type of collagen synthesized by endothelial cells (EC) and is a major constituent of vascular basement membranes. In mouse and man, mutations in genes that encode collagen IV alpha 1 and alpha 2 result in vascular dysfunction. In addition, mutations in genes that encode the Ephrin receptor B4 (EPHB4) and the p120 Ras GTPase-activating protein (RASA1) that cause increased activation of the Ras mitogen-activated protein kinase (MAPK) signaling pathway in EC result in vascular dysfunction as a consequence of impaired export of collagen IV. To understand the pathogenesis of collagen IV-related vascular diseases and phenotypes it is necessary to identify at which times collagen IV is actively synthesized by EC. For this purpose, we used CRISPR/Cas9 targeting in mice to include immediately after the terminal Col4a1 codon a sequence that specifies a P2A peptide followed by enhanced green fluorescent protein (eGFP). Analysis of eGFP expression in Col4a1-P2A-eGFP mice revealed active embryonic EC synthesis of collagen IV alpha 1 through mid to late gestation followed by a sharp decline before birth. These results provide a contextual framework for understanding the basis for the varied vascular abnormalities resulting from perturbation of EC expression and export of functional collagen IV.

Quantitative assessment of glomerular basement membrane collagen IV α chains in paraffin sections from patients with focal segmental glomerulosclerosis and Alport gene variants.

Focal segmental glomerulosclerosis (FSGS) lesions have been linked to variants in COL4A3/A4/A5 genes, which are also mutated in Alport syndrome. Although it could be useful for diagnosis, quantitative evaluation of glomerular basement membrane (GBM) type IV collagen (colIV) networks is not widely used to assess these patients. To do so, we developed immunofluorescence imaging for collagen α5(IV) and α1/2(IV) on kidney paraffin sections with Airyscan confocal microscopy that clearly distinguishes GBM collagen α3α4α5(IV) and α1α1α2(IV) as two distinct layers, allowing quantitative assessment of both colIV networks. The ratios of collagen α5(IV):α1/2(IV) mean fluorescence intensities (α5:α1/2 intensity ratios) and thicknesses (α5:α1/2 thickness ratios) were calculated to represent the levels of collagen α3α4α5(IV) relative to α1α1α2(IV). The α5:α1/2 intensity and thickness ratios were comparable across all 11 control samples, while both ratios were significantly and markedly decreased in all patients with pathogenic or likely pathogenic Alport COL4A variants, supporting validity of this approach. Thus, with further validation of this technique, quantitative measurement of GBM colIV subtype abundance by immunofluorescence, may potentially serve to identify the subgroup of patients with FSGS lesions likely to harbor pathogenic COL4A variants who could benefit from genetic testing.

Increased prevalence of kidney cysts in individuals carrying heterozygous COL4A3 or COL4A4 pathogenic variants.

BACKGROUND: Clinical variability among individuals with heterozygous pathogenic/likely pathogenic (P/LP) variants in the COL4A3/COL4A4 genes (also called autosomal dominant Alport syndrome or COL4A3/COL4A4-related disorder) is huge; many individuals are asymptomatic or show microhematuria, while others may develop proteinuria and chronic kidney disease (CKD). The prevalence of simple kidney cysts (KC) in the general population varies according to age, and patients with advanced CKD are prone to have them. A possible association between heterozygous COL4A3, COL4A4 and COL4A5 P/LP variants and KC has been described in small cohorts. The presence of KC in a multicenter cohort of individuals with heterozygous P/LP variants in the COL4A3/COL4A4 genes is assessed in this study. METHODS: We evaluated the presence of KC by ultrasound in 157 individuals with P/LP variants in COL4A3 (40.7%) or COL4A4 (53.5%) without kidney replacement therapy. The association between presence of KC and age, proteinuria, estimated glomerular filtration rate (eGFR) and causative gene was analyzed. Prevalence of KC was compared with historical case series in the general population. RESULTS: Half of the individuals with P/LP variants in COL4A3/COL4A4 showed KC, which is a significantly higher percentage than in the general population. Only 3.8% (6/157) had cystic nephromegaly. Age and eGFR showed an association with the presence of KC (P < .001). No association was found between KC and proteinuria, sex or causative gene. CONCLUSIONS: Individuals with COL4A3/COL4A4 P/LP variants are prone to develop KC more frequently than the general population, and their presence is related to age and to eGFR. Neither proteinuria, sex nor the causative gene influences the presence of KC in these individuals.

Association of stromal type IV collagen and prognosis in neoadjuvant chemotherapy-treated pancreatic cancer.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) has poor prognosis due to its low surgical eligibility and resistance to chemotherapy. Abundant stroma is characteristic of PDAC, and cancer-associated fibroblasts (CAFs) are a major stromal constituent, contributing to chemoresistance. Because neoadjuvant chemotherapy (NAC) is included in PDAC treatment as a standard regimen, the role of CAFs in NAC resistance must be studied. Although type IV collagen (COLIV) is present in the tumor of PDAC, the association between COLIV and disease advancement of NAC-treated PDAC is unclear. METHODS: Using a cohort of NAC-treated patients with PDAC, we examined clinicopathological data and conducted immunohistochemical analysis of COLIV in tissue specimens prepared from surgically resected pancreas. RESULTS AND CONCLUSIONS: Our analysis revealed that ~50% of the cases were positive for COLIV in the stroma and diffuse COLIV staining was an independent poor prognosis factor alongside high serum CA19-9 before NAC treatment (>37 U/mL) and postsurgical residual tumors. Based on these findings, we propose that stromal COLIV staining can be used to predict prognosis in NAC-treated patients with PDAC after surgery. Additionally, these findings suggest a possibility that stromal COLIV staining indicates resistance to anticancer drugs and/or contributes to malignancy in PDAC.

Escherichia coli induced matrix metalloproteinase-9 activity and type IV collagen degradation is regulated by progesterone in human maternal decidual.

BACKGROUND: Escherichia coli (E. coli) is one of the main bacteria associated with preterm premature rupture of membranes by increasing pro-matrix metalloproteinase 9 (proMMP-9) and degradation of type IV collagen in human feto-maternal interface (HFMi). proMMP-9 is regulated by progesterone (P4) but it is unclear whether P4 inhibits proMMP in human maternal decidual (MDec). This study aimed to determine a role of P4 on proMMP-2 and - 9 and type IV collagen induced by E. coli infection in MDec. METHODS: Nine HFMi were mounted in a Transwell system. MDec was stimulated with P4 or E. coli for 3-, 6-, or 24-hours. proMMP-2, -9 and type IV collagen were assessed. RESULTS: Gelatin zymography revealed an increase in proMMP-9 after 3, 6, and 24 h of stimulating MDec with E. coli. Using immunofluorescence, it was confirmed the increase in the HFMi tissue and a reduction on the amount of type IV collagen leading to the separation of fetal amniochorion and MDEc. The degradative activity of proMMP-9 was reduced by 20% by coincubation with P4. CONCLUSIONS: P4 modulates the activity of proMMP-9 induced by E. coli stimulation but it was unable to completely reverse the degradation of type IV collagen in human MDec tissue.

Trimerization profile of type IV collagen COL4A5 exon deletion in X-linked Alport syndrome.

BACKGROUND: Alport syndrome (AS) is a genetic kidney disease caused by a mutation in type IV collagen α3, α4, and α5, which are normally secreted as heterotrimer α345(IV). Nonsense mutation in these genes causes severe AS phenotype. We previously revealed that the exon-skipping approach to remove a nonsense mutation in α5(IV) ameliorated the AS pathology. However, the effect of removing an exon on trimerization is unknown. Here, we assessed the impact of exon deletion on trimerization to evaluate their possible therapeutic applicability and to predict the severity of mutations associated with exon-skipping. METHODS: We produced exon deletion constructs (ΔExon), nonsense, and missense mutants by mutagenesis and evaluated their trimer formation and secretion activities using a nanoluciferase-based assay that we previously developed. RESULTS: Exon-skipping had differential effects on the trimer secretion of α345(IV). Some ΔExons could form and secrete α345(IV) trimers and had higher activity compared with nonsense mutants. Other ΔExons had low secretion activity, especially for those with exon deletion near the C-terminal end although the intracellular trimerization was normal. No difference was noted in the secretion of missense mutants and their ΔExon counterpart. CONCLUSION: Exon skipping is advantageous for nonsense mutants in AS with severe phenotypes and early onset of renal failure but applications may be limited to ΔExons capable of normal trimerization and secretion. This study provides information on α5(IV) exon-skipping for possible therapeutic application and the prediction of the trimer behavior associated with exon-skipping in Alport syndrome.

Clinical validation of preoperative serum markers for liver fibrosis in living donor liver transplantation recipients.

PURPOSE: To validate the reliability of fibrosis markers as predictors of graft survival in living donor liver transplantation (LDLT) recipients. METHODS: We reviewed data retrospectively, from 163 patients who underwent adult LDLT with preoperative measurements of type IV collagen (CIV), Mac-2 binding protein glycosylation isomer (M2BPGi), and hyaluronic acid (HA). Patients were divided into high and low groups for each biomarker, based on optimal cutoff values, and graft loss within 6 months was evaluated in each group. RESULTS: The high CIV level group showed significantly lower 6-month graft survival rates and significantly higher rates of postoperative sepsis and sepsis from pneumonia. However, the groups with high and low M2BPGi levels and those with high and low HA levels did not show significant differences in 6-month graft survival rates or rates of postoperative sepsis. Multivariate analysis revealed that a CIV level ≥ 590 was a significant predictor of graft loss within 6 months, postoperative sepsis, and sepsis from pneumonia. CONCLUSION: Unlike other fibrosis markers, preoperative CIV levels can predict graft survival, postoperative sepsis, and sepsis from pneumonia after LDLT.

Type IV Collagen Promotes Adipogenic Differentiation of Adipose Stem Cells.

Type IV collagen is a major component of the extracellular matrix in adipose tissue. It is secreted during the lipogenic differentiation of mesenchymal stem cells, but its direct impact and mechanism on the differentiation of adipose-derived stem cells (ASCs) into lipids are unclear. In this study, ASCs were obtained from human liposuction samples and cultured. Lipogenic induction of ASCs was achieved using lipogenic induction medium. Immunofluorescence analysis revealed differential expression of type IV collagen during the early and late stages of adipogenic induction, displaying a distinct morphological encapsulation of ASCs. Silencing of type IV collagen using siRNA resulted in a significant decrease in adipogenic capacity, as indicated by reduced lipid droplet formation and downregulation of adipogenic-related gene transcription. Conversely, supplementation of the culture medium with synthetic type IV collagen demonstrated enhanced adipogenic induction efficiency, accompanied by upregulation of YAP/TAZ protein expression and its downstream target gene transcription. Furthermore, inhibition of the YAP/TAZ pathway using the inhibitor Blebbistatin attenuated the functionality of type IV collagen, leading to decreased lipid droplet formation and downregulation of adipocyte maturation-related gene expression. These findings highlight the crucial role of type IV collagen in promoting adipogenic differentiation of ASCs and suggest its involvement in the YAP/TAZ-mediated Hippo pathway.No Level Assigned This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Exploring the link between Alport syndrome and multiple intracranial artery stenoses: A case report of COL4A5 mutation.

BACKGROUND: Alport syndrome is a genetic disorder caused by mutations in the COL4A5 gene, which encodes type IV collagen α5 chain, leading to chronic nephritis, hearing loss, and ocular abnormalities. Recent reports suggest this genetic mutation may also increase the risk of cerebral aneurysms and fibromuscular dysplasia, indicating a potential association with vascular vulnerability. CASE PRESENTATION: A 66-year-old woman was admitted with recurrent transient weakness of the left hand, which had gradually worsened in duration over three months. Her medical history included chronic nephritis since childhood. Her two sons had end-stage renal disease and hearing loss since their 20s, and her mother also had chronic kidney disease and hearing loss. One son had a history of traumatic subarachnoid hemorrhage, and the other had spinal epidural hematoma. On admission, she had reduced renal function with proteinuria, acute cerebral infarction in the subcortical white matter of the right fronto-parietal and parieto-occipital lobes, and multiple intracranial arterial stenoses (ICAS), including the right middle and right posterior cerebral artery. Vessel wall imaging of the right middle cerebral artery showed a concentric stenotic pattern. Genetic tests identified a pathogenic missense mutation in exon 24 of COL4A5 (exon 24:c.G1700 >C: p.(Gly567Arg)) that was heterozygous for the patient and hemizygous for her son. She was diagnosed with Alport syndrome. CONCLUSION: It is important to consider Alport syndrome as a possible cause of ICAS in patients with a family history of renal failure or hearing loss and to conduct a genetic analysis of type IV collagen genes.

[Improvement of tissue fibrosis in TAFRO syndrome by prednisolone monotherapy].

We report the case of a 48-year-old man who presented with fatigue and weight loss. A local physician observed elevated alkaline phosphatase levels, anemia, thrombocytopenia, and renal dysfunction. Fever also appeared, and the patient was admitted to our hospital. Computed tomography revealed hepatosplenomegaly, pleural and ascitic fluid, and left axillary lymphadenopathy. Bone marrow biopsy indicated hyperplasia with increased megakaryocytes and reticulin fibrosis. Axillary lymph node biopsy showed Castleman's disease-like features. Liver biopsy revealed proliferation of reticulin fibrosis. Therefore, TAFRO syndrome was diagnosed and treatment with 1 mg/kg prednisolone was started. Anemia and thrombocytopenia improved, and after 24 weeks of treatment, serum hyaluronic acid and type IV collagen decreased to the normal range. Bone marrow biopsy after 18 weeks of treatment showed decreased reticular fibers. In TAFRO syndrome, improvement of liver and bone marrow fibrosis can be expected with adequate intervention, and serum hyaluronic acid and type IV collagen are useful for evaluating fibrosis.

Meta-analysis of the diagnostic accuracy of serum type IV collagen 7S concentration for the staging of liver fibrosis in nonalcoholic fatty liver disease.

AIM: We aimed to evaluate the diagnostic accuracy of the measurement of serum type IV collagen 7S (T4C7S) concentration for the staging of liver fibrosis in patients with nonalcoholic fatty liver disease (NAFLD). METHODS: A systematic search or published works was carried out using the PubMed, Cochrane Library, and Web of Science Core Collection databases for studies of the accuracy of serum T4C7S concentration for the staging of fibrosis using Fibrosis stage (F)0-4 in patients with NAFLD diagnosed by liver biopsy. RESULTS: Nine articles describing 1475 participants with NAFLD were included. For fibrosis ≥F1, with n = 849, summary estimates of sensitivity of 0.79, specificity of 0.69, and area under the curve (AUC) of 0.80 were obtained using a median T7C4S cut-off value of 4.6 ng/ml. For fibrosis ≥F2, with n = 1,090, summary estimates of sensitivity of 0.78, specificity of 0.78, and AUC of 0.84 were obtained using a median cut-off value of 4.9 ng/ml. For fibrosis ≥F3, with n = 1311 participants and a median cut-off value of 5.4 ng/ml, a pooled sensitivity of 0.82, specificity of 0.81, and AUC of 0.83 were obtained. For fibrosis ≥F4, with n = 753 and a median cut-off value of 6.6 ng/ml, a pooled sensitivity of 0.85, specificity of 0.81, and AUC of 0.85 were obtained. CONCLUSIONS: Serum T4C7S concentration was found to be an accurate method of staging liver fibrosis in patients with NAFLD.

Variants in genes coding for collagen type IV α-chains are frequent causes of persistent, isolated hematuria during childhood.

BACKGROUND: Children with persistent, isolated microscopic hematuria typically undergo a limited diagnostic workup and are monitored for signs of kidney disease in long-term longitudinal follow-up, which can delay diagnosis and allow disease progression in some cases. METHODS: To determine the clinical utility of genetic screening in this population, we performed targeted genetic testing using a custom, 32-gene next-generation sequencing panel for progressive kidney disease on children referred to the Texas Children's Hospital Pediatric Nephrology clinic for persistent, microscopic hematuria (n = 30; cohort 1). Patients with microscopic hematuria identified by urinalysis on at least two separate occasions were eligible for enrollment, but those with other evidence of kidney disease were excluded. Results were analyzed for sequence variants using the American College of Medical Genetics and Genomics (ACMG) guideline for data interpretation and were validated using a secondary analysis of a dataset of children with hematuria and normal kidney function who had undergone genetic testing as part of an industry-sponsored program (cohort 2; n = 67). RESULTS: In cohort 1 33% of subjects (10/30) had pathogenic or likely pathogenic (P/LP) variants in the type IV collagen genes (COL4A3/A4/A5), and 10% (3/30) had variants of uncertain significance in these genes. The high diagnostic rate in type IV collagen genes was confirmed in cohort 2, where 27% (18/67) of subjects had P/LP variants in COL4A3/A4/A5 genes. CONCLUSIONS: Children with persistent, isolated microscopic hematuria have a high likelihood of having pathogenic variants in type IV collagen genes and genetic screening should be considered. A higher resolution version of the Graphical abstract is available as Supplementary information.

X-linked Alport Syndrome with Type IV Collagen α5 Chain Staining Revealing Normal Expression in the Glomerular Basement Membrane and Negative on Bowman's Capsule and Distal Tubular Basement Membrane: A Case Report.

X-linked Alport syndrome is a hereditary progressive renal disease resulting from the disruption of collagen α3α4α5 (IV) heterotrimerization caused by pathogenic variants in the COL4A5 gene. This study aimed to report a male case of X-linked Alport syndrome with a mild phenotype accompanied by an atypical expression pattern of type IV collagen α5 [α5 (IV)] chain in glomerulus. A 38-year-old male presented with proteinuria (2.3 g/day) and hematuria. He has been detected urinary protein and occult blood since childhood. A renal biopsy was performed at the age of 29 years; however, a diagnosis of Alport syndrome was not considered. A renal biopsy 9 years later revealed diffuse thinning and lamellation of the glomerular basement membrane. Α staining for α5 (IV) revealed a normal expression pattern in the glomerular basement membrane and a complete negative expression in Bowman's capsule and distal tubular basement membrane. Using next-generation sequencing, we detected a COL4A5 missense variant within exon 35 (NM_000495.5: c.3088G>A, p. G1030S). The possibility of X-linked Alport syndrome should be considered when negative expression of α5 (IV) staining on Bowman's capsule was observed.

X-box binding protein 1-mediated COL4A1s secretion regulates communication between vascular smooth muscle and stem/progenitor cells.

Vascular smooth muscle cells (VSMCs) contribute to the deposition of extracellular matrix proteins (ECMs), including Type IV collagen, in the vessel wall. ECMs coordinate communication among different cell types, but mechanisms underlying this communication remain unclear. Our previous studies have demonstrated that X-box binding protein 1 (XBP1) is activated and contributes to VSMC phenotypic transition in response to vascular injury. In this study, we investigated the participation of XBP1 in the communication between VSMCs and vascular progenitor cells (VPCs). Immunofluorescence and immunohistology staining revealed that Xbp1 gene was essential for type IV collagen alpha 1 (COL4A1) expression during mouse embryonic development and vessel wall ECM deposition and stem cell antigen 1-positive (Sca1+)-VPC recruitment in response to vascular injury. The Western blot analysis elucidated an Xbp1 gene dose-dependent effect on COL4A1 expression and that the spliced XBP1 protein (XBP1s) increased protease-mediated COL4A1 degradation as revealed by Zymography. RT-PCR analysis revealed that XBP1s in VSMCs not only upregulated COL4A1/2 transcription but also induced the occurrence of a novel transcript variant, soluble type IV collagen alpha 1 (COL4A1s), in which the front part of exon 4 is joined with the rear part of exon 42. Chromatin-immunoprecipitation, DNA/protein pulldown and in vitro transcription demonstrated that XBP1s binds to exon 4 and exon 42, directing the transcription from exon 4 to exon 42. This leads to transcription complex bypassing the internal sequences, producing a shortened COL4A1s protein that increased Sca1+-VPC migration. Taken together, these results suggest that activated VSMCs may recruit Sca1+-VPCs via XBP1s-mediated COL4A1s secretion, leading to vascular injury repair or neointima formation.

A novel nanoluciferase transgenic reporter measures proteinuria in zebrafish.

The zebrafish is an important animal system for modeling human diseases. This includes kidney dysfunction as the embryonic kidney (pronephros) shares considerable molecular and morphological homology with the human nephron. A key clinical indicator of kidney disease is proteinuria, but a high-throughput readout of proteinuria in the zebrafish is currently lacking. To remedy this, we used the Tol2 transposon system to generate a transgenic zebrafish line that uses the fabp10a liver-specific promoter to over-express a nanoluciferase molecule fused with the D3 domain of Receptor-Associated Protein (a type of molecular chaperone) which we term NL-D3. Using a luminometer, we quantified proteinuria in NL-D3 zebrafish larvae by measuring the intensity of luminescence in the embryo medium. In the healthy state, NL-D3 is not excreted, but when embryos were treated with chemicals that affected either proximal tubular reabsorption (cisplatin, gentamicin) or glomerular filtration (angiotensin II, Hanks Balanced Salt Solution, Bovine Serum Albumin), NL-D3 is detected in fish medium. Similarly, depletion of several gene products associated with kidney disease (nphs1, nphs2, lrp2a, ocrl, col4a3, and col4a4) also induced NL-D3 proteinuria. Treating col4a4 depleted zebrafish larvae (a model of Alport syndrome) with captopril reduced proteinuria in this system. Thus, our findings validate the use of the NL-D3 transgenic zebrafish as a robust and quantifiable proteinuria reporter. Hence, given the feasibility of high-throughput assays in zebrafish, this novel reporter will permit screening for drugs that ameliorate proteinuria, thereby prioritizing candidates for further translational studies.

Periapical lesion following Cnm-positive Streptococcus mutans pulp infection worsens cerebral hemorrhage onset in an SHRSP rat model.

Cerebral hemorrhage severely affects the daily life of affected individuals. Streptococcus mutans and its adhesion factor Cnm increase the adverse effects of cerebral hemorrhages. However, the mechanism by which Cnm-positive bacteria migrate from apical lesions to cerebral hemorrhage sites is unclear. Therefore, we established an S. mutans-infected apical lesion in a rat model of hypertension and investigated the neurological symptoms associated with cerebral hemorrhage. Eighteen 12-week-old stroke-prone spontaneously hypertensive rats were randomly divided into three groups, i.e. the no infection (control), dental infection with S. mutans KSM153 wild type (Cnm positive), and KSM153 Δcnm groups. Immunofluorescent staining was performed to visualize S. mutans protein. Serum interleukin-1ß levels were measured. The adhesion of S. mutans to the extracellular matrix and human fibroblast cells was also analyzed. Serum antibody titers against S. mutans were comparable between Cnm positive and knockout mutants. However, 3-10 days post-infection, neurological symptom scores and cerebral hemorrhage scores were higher in Cnm-positive rats than in knockout mutants. The localization of S. mutans-derived protein was observed in the vicinity of disrupted blood vessels. Serum interleukin-1ß levels significantly increased post-KSM153 WT infection. Cnm-positive S. mutans clinical isolates showed increased adhesion to the extracellular matrix, human dental pulp cells, and human umbilical vein endothelial cells compared with the Cnm-negative S. mutans isolates. In conclusion, Cnm-positive bacteria colonize the apical lesion site using the extracellular matrix as a foothold and affect cerebral hemorrhage via the bloodstream.

Lifelong effect of therapy in young patients with the COL4A5 Alport missense variant p.(Gly624Asp): a prospective cohort study.

BACKGROUND: Angiotensin-converting enzyme inhibitors (ACEis) have evolved as a first-line therapy for delaying end-stage renal failure (ESRF) in Alport syndrome (AS). The present study tested the hypothesis of a superior nephroprotective potential of an early ACEi intervention, examining a cohort with the COL4A5 missense variant p.(Gly624Asp). METHODS: In this observational cohort study (NCT02378805), 114 individuals with the identical gene variant were explored for age at ESRF and life expectancy in correlation with treatment as endpoints. RESULTS: All 13 untreated hemizygous patients developed ESRF (mean age 48.9 ± 13.7 years), as did 3 very late treated hemizygotes (51.7 ± 4.2 years), with a mean life expectancy of 59.2 ± 9.6 years. All 28 earlier-treated [estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2] hemizygous patients were still alive and still had not reached ESRF. Therapy minimized the annual loss of their GFR, similar to the annual loss in healthy individuals. Of 65 heterozygotes, 4 untreated individuals developed ESRF at an age of 53.3 ± 20.7 years. None of the treated heterozygous females developed ESRF. CONCLUSIONS: For the first time, this study shows that in AS, early therapy in individuals with missense variants might have the potential to delay renal failure for their lifetime and thus to improve life expectancy and quality of life without the need for renal replacement therapy. Some treated patients have reached their retirement age with still-functioning kidneys, whereas their untreated relatives have reached ESRF at the same or a younger age. Thus, in children with glomerular haematuria, early testing for Alport-related gene variants could lead to timely nephroprotective intervention.

Correlation between serum liver fibrosis markers and early gastroesophageal varices among patients with compensated liver cirrhosis: a cross-sectional analysis.

BACKGROUND AND AIM: Portal hypertension is a common complication of chronic liver diseases responsible for most liver cirrhosis consequences. In patients with portal hypertension, oesophagogastric variceal bleeding is a leading cause of death. Most research has focused on high-risk gastroesophageal varices and bleeding, with only a few studies on early varices. However, early intervention of gastroesophageal varices was found to better improve the prognosis and reduce mortality, but there is still no relevant research. Ultrasonic endoscopy is a combination of endoscopy and ultrasonic imaging. It can gastroscopically detect varices around the oesophagus and stomach and detect oesophageal collateral veins and perforating veins earlier, which is helpful for the early diagnosis of varices. Therefore, this study aimed to explore the correlation between serum fibrosis markers and early gastroesophageal varices in compensated cirrhosis patients. METHODS: This study included 791 patients with compensated cirrhosis. The selected patients were categorized into three groups. The early gastroesophageal varices group included patients with gastroesophageal varices found by endoscopic ultrasonography but not by gastroscopy. The no gastroesophageal varices group underwent endoscopic ultrasonography and gastroscopy without varices. In addition, gastroesophageal varices can be detected with both techniques. Multiple logistic regression analysis explored the association of serum fibrosis markers with early gastroesophageal varices. RESULTS: Among the 791 compensated liver cirrhosis patients, 198 patients were without gastroesophageal varices, 279 patients had early gastroesophageal varices, 314 patients had gastroesophageal varices, and both techniques could detect varices. There was a positive correlation between serum fibrosis markers and early gastroesophageal varices. In univariate logistic regression analysis, the patients with early gastroesophageal varices had lower platelet counts (P = 0.034) and higher aspartate aminotransferase (P = 0.046), total bilirubin (P = 0.041), hyaluronic acid (P < 0.001), laminin (P < 0.001), type III procollagen (P = 0.005), type IV collagen (P = 0.002), liver stiffness measurement (P = 0.001), APRI (P = 0.019) and FIB-4 (P = 0.002). Multivariate analysis showed that laminin (OR 1.011; 95% CI 1.004-1.017, P = 0.001) was an independent risk factor for predicting early gastroesophageal varices in compensated cirrhosis patients. CONCLUSION: Higher laminin was independently associated with early gastroesophageal varices in compensated cirrhosis patients.

The expression of stromal biomarkers in small papillary thyroid carcinomas.

BACKGROUND: The importance of stroma for tumor progression is recognized for many cancer types. In this study, we aim to evaluate the expression of types I (Col1) and IV (Col4) collagens, alpha-smooth muscle actin (a-SMA), and matrix metallopeptidase 9 (MMP-9) in the tumor stroma of small papillary thyroid carcinoma (PTC). MATERIAL AND METHODS: Twenty-five non-metastatic small PTCs (pT1N0) and nineteen metastatic small PTCs (pT1N1b) including corresponding metastatic lateral lymph nodes were selected and paraffinized tissue blocks retrieved. The samples were stained for Col1, COL4, a-SMA, and MMP-9 antibodies using immunohistochemistry. The expression of the stromal proteins was scored and analyzed based on the location, intensity, and distribution. RESULTS: Col1 and Col4 expression were significantly higher in normal thyroid tissue compared to PTC tissue. On the contrary, expression of a-SMA and MMP-9 was higher in PTC tissue compared to normal thyroid tissue. Both Col1 and Col4 were significantly more highly expressed in the non-metastatic tumors compared with metastatic tumors. The expression of a-SMA and MMP9 was slightly, but not significantly, higher in the metastasized tumors and their respective lymph nodes. There was a significant correlation between the metastasized tumors and their respective lymph nodes in Col1 and MMP-9 expression. CONCLUSIONS: Col1, Col4, a-SMA, and MMP-9 expression in PTCs differs significantly from that of normal thyroid tissue. The higher expression of Col1 and Col4 in normal thyroid tissue and in the non-metastasized tumors indicates that Col1 and 4 might have a potential protective role in tumor progression. The higher expression of a-SMA and MMP9 in PTCs indicates that these proteins might have a role in promoting PTC progression and aggressiveness.

Identification of an Altered Matrix Signature in Kidney Aging and Disease.

BACKGROUND: Accumulation of extracellular matrix in organs and tissues is a feature of both aging and disease. In the kidney, glomerulosclerosis and tubulointerstitial fibrosis accompany the decline in function, which current therapies cannot address, leading to organ failure. Although histologic and ultrastructural patterns of excess matrix form the basis of human disease classifications, a comprehensive molecular resolution of abnormal matrix is lacking. METHODS: Using mass spectrometry-based proteomics, we resolved matrix composition over age in mouse models of kidney disease. We compared the changes in mice with a global characterization of human kidneymatrix during aging and to existing kidney disease datasets to identify common molecular features. RESULTS: Ultrastructural changes in basement membranes are associated with altered cell adhesion and metabolic processes and with distinct matrix proteomes during aging and kidney disease progression in mice. Within the altered matrix, basement membrane components (laminins, type IV collagen, type XVIII collagen) were reduced and interstitial matrix proteins (collagens I, III, VI, and XV; fibrinogens; and nephronectin) were increased, a pattern also seen in human kidney aging. Indeed, this signature of matrix proteins was consistently modulated across all age and disease comparisons, and the increase in interstitial matrix was also observed in human kidney disease datasets. CONCLUSIONS: This study provides deep molecular resolution of matrix accumulation in kidney aging and disease, and identifies a common signature of proteins that provides insight into mechanisms of response to kidney injury and repair.