Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 47
Filter
1.
Angiogenesis ; 27(3): 461-474, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38780883

ABSTRACT

The presence of atherosclerotic plaque vessels is a critical factor in plaque destabilization. This may be attributable to the leaky phenotype of these microvessels, although direct proof for this notion is lacking. In this study, we investigated molecular and cellular patterns of stable and hemorrhaged human plaque to identify novel drivers of intraplaque vessel dysfunction. From transcriptome data of a human atherosclerotic lesion cohort, we reconstructed a co-expression network, identifying a gene module strongly and selectively correlated with both plaque microvascular density and inflammation. Spectrin Beta Non-Erythrocytic 1 (sptbn1) was identified as one of the central hubs of this module (along with zeb1 and dock1) and was selected for further study based on its predominant endothelial expression. Silencing of sptbn1 enhanced leukocyte transmigration and vascular permeability in vitro, characterized by an increased number of focal adhesions and reduced junctional VE-cadherin. In vivo, sptbn1 knockdown in zebrafish impaired the development of the caudal vein plexus. Mechanistically, increased substrate stiffness was associated with sptbn1 downregulation in endothelial cells in vitro and in human vessels. Plaque SPTBN1 mRNA and protein expression were found to correlate with an enhanced presence of intraplaque hemorrhage and future cardiovascular disease (CVD) events during follow-up. In conclusion, we identify SPTBN1 as a central hub gene in a gene program correlating with plaque vascularisation. SPTBN1 was regulated by substrate stiffness in vitro while silencing blocked vascular development in vivo, and compromised barrier function in vitro. Together, SPTBN1 is identified as a new potential regulator of the leaky phenotype of atherosclerotic plaque microvessels.


Subject(s)
Microvessels , Plaque, Atherosclerotic , Spectrin , Zebrafish , Animals , Humans , Capillary Permeability , Human Umbilical Vein Endothelial Cells/metabolism , Microvessels/pathology , Microvessels/metabolism , Phenotype , Plaque, Atherosclerotic/pathology , Plaque, Atherosclerotic/genetics , Plaque, Atherosclerotic/metabolism , Spectrin/genetics , Spectrin/metabolism , Transcriptome , Zebrafish/genetics
2.
Angiogenesis ; 27(1): 23-35, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37326760

ABSTRACT

Patients with chronic kidney disease (CKD) have an increased risk for cardiovascular morbidity and mortality. Capillary rarefaction may be both one of the causes as well as a consequence of CKD and cardiovascular disease. We reviewed the published literature on human biopsy studies and conclude that renal capillary rarefaction occurs independently of the cause of renal function decline. Moreover, glomerular hypertrophy may be an early sign of generalized endothelial dysfunction, while peritubular capillary loss occurs in advanced renal disease. Recent studies with non-invasive measurements show that capillary rarefaction is detected systemically (e.g., in the skin) in individuals with albuminuria, as sign of early CKD and/or generalized endothelial dysfunction. Decreased capillary density is found in omental fat, muscle and heart biopsies of patients with advanced CKD as well as in skin, fat, muscle, brain and heart biopsies of individuals with cardiovascular risk factors. No biopsy studies have yet been performed on capillary rarefaction in individuals with early CKD. At present it is unknown whether individuals with CKD and cardiovascular disease merely share the same risk factors for capillary rarefaction, or whether there is a causal relationship between rarefaction in renal and systemic capillaries. Further studies on renal and systemic capillary rarefaction, including their temporal relationship and underlying mechanisms are needed. This review stresses the importance of preserving and maintaining capillary integrity and homeostasis in the prevention and management of renal and cardiovascular disease.


Subject(s)
Cardiovascular Diseases , Microvascular Rarefaction , Renal Insufficiency, Chronic , Vascular Diseases , Humans , Capillaries/pathology , Cardiovascular Diseases/pathology , Microvascular Rarefaction/pathology , Kidney/pathology , Renal Insufficiency, Chronic/pathology , Vascular Diseases/pathology
3.
Int J Mol Sci ; 24(6)2023 Mar 21.
Article in English | MEDLINE | ID: mdl-36983004

ABSTRACT

Perinatal brain injury following hypoxia-ischemia (HI) is characterized by high mortality rates and long-term disabilities. Previously, we demonstrated that depletion of Annexin A1, an essential mediator in BBB integrity, was associated with a temporal loss of blood-brain barrier (BBB) integrity after HI. Since the molecular and cellular mechanisms mediating the impact of HI are not fully scrutinized, we aimed to gain mechanistic insight into the dynamics of essential BBB structures following global HI in relation to ANXA1 expression. Global HI was induced in instrumented preterm ovine fetuses by transient umbilical cord occlusion (UCO) or sham occlusion (control). BBB structures were assessed at 1, 3, or 7 days post-UCO by immunohistochemical analyses of ANXA1, laminin, collagen type IV, and PDGFRß for pericytes. Our study revealed that within 24 h after HI, cerebrovascular ANXA1 was depleted, which was followed by depletion of laminin and collagen type IV 3 days after HI. Seven days post-HI, increased pericyte coverage, laminin and collagen type IV expression were detected, indicating vascular remodeling. Our data demonstrate novel mechanistic insights into the loss of BBB integrity after HI, and effective strategies to restore BBB integrity should potentially be applied within 48 h after HI. ANXA1 has great therapeutic potential to target HI-driven brain injury.


Subject(s)
Annexin A1 , Brain Injuries , Hypoxia-Ischemia, Brain , Female , Pregnancy , Animals , Sheep , Humans , Animals, Newborn , Hypoxia-Ischemia, Brain/metabolism , Annexin A1/metabolism , Laminin/metabolism , Collagen Type IV/metabolism , Brain Injuries/metabolism , Brain/metabolism
4.
PLoS One ; 18(1): e0279944, 2023.
Article in English | MEDLINE | ID: mdl-36662718

ABSTRACT

Extracellular histones are cytotoxic molecules involved in experimental acute kidney injury. In patients receiving a renal transplant from donors after circulatory death, who suffer from additional warm ischemia, worse graft outcome is associated with higher machine perfusate extracellular histone H3 concentrations. We now investigated temperature-dependent extracellular histone release in an ex vivo porcine renal perfusion model, and subsequently studied histone release in the absence and presence of non-anticoagulant heparin. Seven pairs of ischemically damaged porcine kidneys were machine perfused at 4°C (cold ischemia) or 28°C (warm ischemia). Perfusate histone H3 concentration was higher after warm as compared to cold ischemia (median (IQR) = 0.48 (0.20-0.83) µg/mL vs. 0.02 (0.00-0.06) µg/mL; p = .045, respectively). Employing immune-electron microscopy (EM), histone containing cytoplasmic protrusions of tubular and endothelial cells were found after warm ischemic injury. Furthermore, abundant histone localization was detected in debris surrounding severely damaged glomerular cells, in a "buck shot" pattern. In vitro, histones were cytotoxic to endothelial and kidney epithelial cells in a temperature-dependent manner. In a separate ex vivo experiment, addition of heparin did not change the total histone H3 levels observed in the perfusate but revealed a continuous increase in the level of a lower molecular weight histone H3 variant. Our findings show that ischemically damaged kidneys release more extracellular histones in warm ischemia, which by EM was due to histone release by renal cells. Blocking of histone-mediated damage during transplantation may be beneficial in prevention of renal injury.


Subject(s)
Cold Injury , Histones , Swine , Animals , Endothelial Cells , Organ Preservation , Perfusion , Kidney , Ischemia , Warm Ischemia
5.
Histopathology ; 82(5): 713-721, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36579371

ABSTRACT

AIMS: In current renal transplant pathology practice, interstitial fibrosis is visually assessed in categories according to the Banff classification. As this has a moderate reproducibility, which is little ameliorated by morphometric analysis, we investigated whether visual renal fibrosis assessment is feasible on a continuous scale, i.e. as a percentage of affected area of the cortex. METHODS AND RESULTS: Protocol renal biopsies taken at transplantation (n = 125), three (n = 73) and 12 months (n = 88) after transplantation were visually scored in categories (Banff) and percentages for interstitial fibrosis (ci). Interobserver variation (ICC and weighted κ) was assessed, and morphometric analysis on Sirius red-stained sections was performed. Correlations between the different methods and their association with donor age and eGFR 1 and 5 years post-transplant were analysed using Pearson's or Spearman's rho. Interobserver agreement was equivalent for Banff and %ci (κ = 0.713 versus ICC = 0.792), and for Banff IF/TA and %IF/TA (κ = 0.615 versus ICC = 0.743). Both Banff and %ci were associated with Sirius red morphometry in 3 and 12 months. With all three methods, a significant correlation was found between donor age and fibrosis in the implantation biopsy and between fibrosis in the 12 months' biopsy and eGFR at 1 and 5 years (eGFR at 1 year: Sirius red ρ = 0.487, %ci ρ = 0.393, Banff ρ = 0.413, all P < 0.01, eGFR at 5 years: Sirius red ρ = 0.392, %ci ρ = 0.333, Banff ρ = 0.435, all P < 0.01). CONCLUSION: Interstitial fibrosis assessment on a continuous scale can be used next to scoring in categories according to the Banff classification in protocol renal transplant biopsies.


Subject(s)
Kidney Transplantation , Humans , Infant , Reproducibility of Results , Kidney/pathology , Biopsy , Fibrosis , Coloring Agents , Graft Rejection/pathology
6.
Int J Mol Sci ; 23(22)2022 Nov 10.
Article in English | MEDLINE | ID: mdl-36430335

ABSTRACT

Myocardial infarction is the most common cause of death worldwide. An understanding of the alterations in protein pathways is needed in order to develop strategies that minimize myocardial damage. To identify the protein signature of cardiac ischemia/reperfusion (I/R) injury in rats, we combined, for the first time, protein matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) and label-free proteomics on the same tissue section placed on a conductive slide. Wistar rats were subjected to I/R surgery and sacrificed after 24 h. Protein MALDI-MSI data revealed ischemia specific regions, and distinct profiles for the infarct core and border. Firstly, the infarct core, compared to histologically unaffected tissue, showed a significant downregulation of cardiac biomarkers, while an upregulation was seen for coagulation and immune response proteins. Interestingly, within the infarct tissue, alterations in the cytoskeleton reorganization and inflammation were found. This work demonstrates that a single tissue section can be used for protein-based spatial-omics, combining MALDI-MSI and label-free proteomics. Our workflow offers a new methodology to investigate the mechanisms of cardiac I/R injury at the protein level for new strategies to minimize damage after MI.


Subject(s)
Coronary Artery Disease , Myocardial Infarction , Reperfusion Injury , Animals , Rats , Rats, Wistar , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Myocardial Infarction/pathology , Reperfusion
8.
Pediatr Nephrol ; 36(7): 1673-1681, 2021 07.
Article in English | MEDLINE | ID: mdl-32880745

ABSTRACT

Prematurity and perinatal stress, such as intrauterine growth restriction (IUGR) and chorioamnionitis, are pathological processes creating an impaired intrauterine environment. These intrauterine factors are associated with the development of proteinuria, hypertension, and chronic kidney disease (CKD) later in life. Initially, this was thought to be secondary to oligonephropathy, subsequent glomerular hypertrophy, and hyperfiltration, leading to glomerulosclerosis, a further decrease in nephron number, and finally CKD. Nowadays, there is increasing evidence that prematurity and perinatal stress affect not only nephron endowment but also the maturation of podocytes and vasculogenesis. IUGR is associated with podocyte damage and an aggravated course of nephrotic syndrome. Moreover, preterm birth and IUGR are known to cause upregulation of the postnatal renin-angiotensin system, resulting in hypertension. Chorioamnionitis causes damage to the glomeruli, thereby predisposing to the development of glomerulosclerosis. This review aims to summarize current knowledge on the influence of prematurity, IUGR, and chorioamnionitis on the development of different glomerular structures. After summarizing human and experimental data on low nephron number in general, a specific focus on the current understanding of podocyte and glomerular capillary formation in relation to prematurity and different causes of perinatal stress is presented.


Subject(s)
Chorioamnionitis , Hypertension , Infant, Newborn, Diseases , Infant, Premature, Diseases , Podocytes , Premature Birth , Renal Insufficiency, Chronic , Disease Susceptibility , Female , Fetal Growth Retardation , Humans , Infant, Newborn , Pregnancy , Renal Insufficiency, Chronic/etiology
9.
Transplantation ; 104(12): 2567-2574, 2020 12.
Article in English | MEDLINE | ID: mdl-33215902

ABSTRACT

BACKGROUND: During organ retrieval, surgeons estimate the degree of arteriosclerosis and this plays an important role in decisions on organ acceptance. Our study aimed to elucidate the association between macroscopic renal artery arteriosclerosis, donor kidney discard, and transplant outcome. METHODS: We selected all transplanted and discarded kidneys in the Netherlands between January 1, 2000, and December 31, 2015, from deceased donors aged 50 y and older, for which data on renal artery arteriosclerosis were available (n = 2610). The association between arteriosclerosis and kidney discard, the relation between arteriosclerosis and outcome, and the correlation between macroscopic and microscopic arteriosclerosis were explored. RESULTS: Macroscopic arteriosclerosis was independently associated with kidney discard (odds ratio [OR], 1.36; 95% confidence interval [CI], 1.02-1.80; P = 0.03). Arteriosclerosis (any degree) was not significantly associated with delayed graft function (OR, 1.16; 95% CI, 0.94-1.43; P = 0.16), estimated glomerular filtration rate 1-y posttransplant (B, 0.58; 95% CI, -2.07 to 3.22; P = 0.67), and long-term graft survival (hazard ratio, 1.07; 95% CI, 0.86-1.33; P = 0.55). There was a significant association between mild arteriosclerosis and primary nonfunction (OR, 2.14; 95% CI, 1.19-3.84; P = 0.01). We found no correlation between macroscopic and histological arteriosclerosis, nor between histological arteriosclerosis and transplant outcome. CONCLUSIONS: Macroscopic arteriosclerosis of the renal artery was independently associated with kidney discard and somewhat associated with primary nonfunction posttransplant. However, there was no effect of arteriosclerosis on delayed graft function, estimated glomerular filtration rate at 1 y, or long-term graft survival. Our results are valid only after inevitable exclusion of discarded kidneys that had on average more arteriosclerosis. Hence, conclusions should be interpreted in the light of this potential bias.


Subject(s)
Arteriosclerosis/complications , Donor Selection , Kidney Transplantation , Renal Artery , Tissue Donors , Aged , Aged, 80 and over , Arteriosclerosis/pathology , Delayed Graft Function/etiology , Delayed Graft Function/physiopathology , Female , Glomerular Filtration Rate , Graft Survival , Health Status , Humans , Kidney Transplantation/adverse effects , Male , Middle Aged , Netherlands , Primary Graft Dysfunction/etiology , Primary Graft Dysfunction/physiopathology , Renal Artery/pathology , Retrospective Studies , Risk Assessment , Risk Factors , Time Factors , Treatment Outcome
10.
Anal Chem ; 90(24): 14198-14206, 2018 12 18.
Article in English | MEDLINE | ID: mdl-30422637

ABSTRACT

Diffuse large B-cell lymphoma (DLBCL) is the most common B-cell non-Hodgkin lymphoma. To treat this aggressive disease, R-CHOP, a combination of immunotherapy (R; rituximab) and chemotherapy (CHOP; cyclophosphamide, doxorubicin, vincristine, and prednisone), remains the most commonly used regimen for newly diagnosed DLBCLs. However, up to one-third of patients ultimately becomes refractory to initial therapy or relapses after treatment, and the high mortality rate highlights the urgent need for novel therapeutic approaches based upon selective molecular targets. In order to understand the molecular mechanisms underlying relapsed DLBCL, we studied differences in the lipid and metabolic composition of nontreated and R-CHOP-resistant tumors, using a combination of in vivo DLBCL xenograft models and mass spectrometry imaging. Together, these techniques provide information regarding analyte composition and molecular distributions of therapy-resistant and sensitive areas. We found specific lipid and metabolic profiles for R-CHOP-resistant tumors, such as a higher presence of phosphatidylinositol and sphingomyelin fragments. In addition, we investigated intratumor heterogeneity and identified specific lipid markers of viable and necrotic areas. Furthermore, we could monitor metabolic changes and found reduced adenosine triphosphate and increased adenosine monophosphate in the R-CHOP-resistant tumors. This work highlights the power of combining in vivo imaging and MSI to track molecular signatures in DLBCL, which has potential application for other diseases.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Lipids/analysis , Lymphoma, Large B-Cell, Diffuse/drug therapy , Metabolome , Rituximab/therapeutic use , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Adenosine Triphosphate/metabolism , Animals , Cell Line, Tumor , Discriminant Analysis , Drug Resistance, Neoplasm , Humans , Luminescent Measurements , Lymphoma, Large B-Cell, Diffuse/metabolism , Lymphoma, Large B-Cell, Diffuse/pathology , Mice , Neoplasm Recurrence, Local , Phosphatidylinositols/analysis , Principal Component Analysis , Transplantation, Heterologous
11.
J Surg Res ; 229: 271-276, 2018 09.
Article in English | MEDLINE | ID: mdl-29937000

ABSTRACT

BACKGROUND: Hernia repair is one of the most frequently performed operations. In search of the ideal mesh for hernia repair, animal research is required. Although rats are most often used in experimental mesh experiments, no correlation with clinical findings in humans has ever been shown. Therefore, the aim of our study was to investigate whether adhesion formation and foreign body reactions to meshes in rats are comparable with the reactions in humans. MATERIALS AND METHODS: A fixed type of mesh was implanted intraperitoneally in a group of 10 rats and 10 patients undergoing elective, temporary stoma formation. In case of the latter, meshes were placed around the stoma. After a follow-up period of 12 wk in rats and after a median follow-up of 6 mo in humans, samples of the mesh were collected. Adhesion assessments were performed, and (immuno-) histochemical evaluation was performed by a specialized experimental pathologist and an experienced clinical pathologist. RESULTS: After the follow-up period, adhesion formation did not differ significantly between rats and humans. Moreover, general inflammation scores were comparable, although granulocytes and giant cells were more present in rats, compared with humans. On the other hand, the presence of fibrosis was more evident in humans compared with rats. CONCLUSIONS: To our knowledge, this is the first study, which showed that a specific animal model, namely a rat model, correlates with adhesion formation and the foreign body reaction to meshes in humans. It can be recommended to use rats in future experimental mesh for incisional hernia research.


Subject(s)
Disease Models, Animal , Foreign-Body Reaction/pathology , Hernia, Abdominal/surgery , Herniorrhaphy/adverse effects , Rats , Surgical Mesh/adverse effects , Tissue Adhesions/pathology , Abdominal Wall/pathology , Abdominal Wall/surgery , Aged , Animals , Female , Fibrosis , Follow-Up Studies , Foreign-Body Reaction/etiology , Herniorrhaphy/instrumentation , Humans , Male , Middle Aged , Peritoneal Cavity/pathology , Rats, Wistar , Species Specificity , Tissue Adhesions/etiology
12.
JAMA Otolaryngol Head Neck Surg ; 144(3): 211-217, 2018 Mar 01.
Article in English | MEDLINE | ID: mdl-29327047

ABSTRACT

IMPORTANCE: Many patients with an open radical mastoid cavity experience therapy-resistant otorrhea. Little is known about the underlying histopathological substrate of unstable cavities and the correlation with treatment failure. OBJECTIVE: To study the histopathological and inflammatory features of chronically discharging open radical mastoid cavities and the influence of different treatments. DESIGN, SETTING, AND PARTICIPANTS: This secondary analysis of a randomized clinical trial was a histopathology study of tissue samples of a cohort of 30 patients with a chronically discharging open mastoid cavity. Samples were taken from the cavities, which were treated with either honey gel or conventional eardrops in a tertiary center between 2012 and 2013. Tissue staining was performed in May 2014; final computer analysis/correlation studies were performed in June 2016. MAIN OUTCOMES AND MEASURES: Differences of epithelial tissue coverage, infiltration of T cells (CD3, CD4, CD8) and macrophage (CD68, isoenzyme nitric oxide synthase, arginase 1) (sub-)populations, infection status, and the correlation with clinical presentation. RESULTS: There were 30 patients (24 [80%] male; mean [SD] age, 59 [14] years). Cavities were covered with either stratified squamous (keratinized) epithelium (n = 10), respiratory columnar epithelium (n = 9), or granulation tissue (n = 10). The presence of respiratory epithelium was associated with lower treatment success (posttreatment VAS improvement of 3.1 [95% CI, 0.5 to 5.8] for discomfort and 3.6 [95% CI, 0.2 to 6.9] for otorrhea in the group with granulation tissue coverage vs 4.9 [95% CI, 0.2 to 9.6] and 5.8 [95% CI, -0.1 to 11.6] in the group with squamous [keratinized] epithelium coverage and 1.4 [95% CI, -1.2 to 4.1] and 2.5 [95% CI, -1.3 to 6.2] in the group with respiratory columnar epithelium coverage). In all 3 tissue types of cavity-covering tissues, T-cell infiltrates consisted of helper T cells and cytotoxic T cells, together with a lower number of macrophages. The immunopositivity for isoenzyme nitric oxide synthase and arginase 1 was high and not restricted to a macrophage subpopulation, but seen in various cell types. Inflammatory infiltrations varied strongly in all 3 tissue modalities. CONCLUSIONS AND RELEVANCE: Discharging open mastoid cavities can be classified histologically into 3 different types, based on their coverage: squamous epithelium, respiratory epithelium, or granulation tissue. Treatment is less successful in cavities covered with respiratory epithelium, possibly explained by the status of bacterial infection and local immunological differences.


Subject(s)
Mastoid/pathology , Otitis Media with Effusion/pathology , Chronic Disease , Epithelial Cells/pathology , Female , Granulation Tissue/pathology , Humans , Male , Middle Aged , Respiratory Mucosa/pathology
13.
Oral Oncol ; 66: 14-21, 2017 03.
Article in English | MEDLINE | ID: mdl-28249643

ABSTRACT

BACKGROUND: The local recurrence rate in oral squamous cell cancer (OSCC) hardly decreases. This is partly due to the presence of (pre)malignant cells in the remaining tissue after resection, that may lead to the development of a new tumor in time. Detection of histologically (pre)malignant cells in the tumor resection margins should predict these patients at risk for recurrence, however this appears to be difficult in routine practice. Purpose of this study was to apply easy-to-use molecular tests for more accurate detection of (pre)malignant cells in histopathologically tumor-free margins, to improve diagnosis of patients at risk. METHODS: 42 patients with firstly diagnosed, radically resected primary OSCC with histopathologically confirmed tumor-free resection margins (treated between 1994 and 2003) were included. Inclusion criteria comprised of follow-up ⩾5years, and radical surgery without postoperative treatment. Formalin-fixed paraffine-embedded tissue sections of 42 tumors, 290 resection margins, and 11 recurrences were subjected to fluorescence in situ hybridization (FISH) to examine chromosome 1 and 7 copy number variations (CNV), and to p53 immunohistochemistry (IHC). RESULTS: 11 out of the 42 patients developed a local recurrence within 5years. FISH analysis showed that nine of eleven recurrences exhibited CI in at least one of the resection margins (p=0.008). P53 overexpression and routine histopathologic classification were not correlated with recurrent disease. The presence of CI in the resection margins revealed a significantly worse progression-free survival (log-rank p=0.012). CONCLUSIONS: CI in the resection margins of OSCC can reliably identify patients at risk for developing a local recurrence.


Subject(s)
Carcinoma, Squamous Cell/genetics , Chromosomal Instability , Mouth Neoplasms/genetics , Neoplasm Recurrence, Local , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/surgery , Chromosomes, Human, Pair 1 , Chromosomes, Human, Pair 7 , Female , Humans , In Situ Hybridization, Fluorescence , Male , Middle Aged , Mouth Neoplasms/pathology , Mouth Neoplasms/surgery
14.
Transplantation ; 100(4): 916-24, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26371598

ABSTRACT

BACKGROUND: Data on the outcome of renal transplantation in antineutrophil cytoplasmic antibody-associated glomerulonephritis (AAGN) patients are still limited. In particular, how disease recurrence in the renal allograft defines graft outcome is largely unknown. Therefore, we conducted a multicenter observational clinical and histopathological study to establish recurrence rate of AAGN in the allograft and the impact of recurrence on allograft survival. METHODS: Using the nationwide Dutch Pathology Registry (PALGA), we retrospectively collected clinical and histopathological data of consecutive AAGN patients who had developed end-stage renal failure and received a kidney allograft in 1 of 6 Dutch university hospitals between 1984 and 2011. Transplant biopsies were scored using the Banff '09 classification. Renal disease recurrence was scored using the histopathological classification of AAGN. RESULTS: The posttransplantation recurrence rate of AAGN was 2.8% per patient year, accumulating to recurrence in a total of 11 of 110 AAGN patients within the first 5 years after transplantation. Four of these 11 patients lost their graft, with 1-year and 5-year graft survival rates of 94.5% and 82.8%, respectively. By multivariate analysis, AAGN recurrence was independently associated with subsequent graft loss. CONCLUSIONS: In this study in 110 Dutch patients, the recurrence rate of AAGN within 5 years after kidney transplantation appeared slightly higher than in previous reports. Moreover, recurrence of AAGN contributed independently to kidney allograft loss, emphasizing the importance of clinical vigilance, because early treatment might be critical to rescuing the allograft.


Subject(s)
Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/surgery , Glomerulonephritis/surgery , Kidney Transplantation , Adolescent , Adult , Aged , Allografts , Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/diagnosis , Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/immunology , Biopsy , Female , Glomerulonephritis/diagnosis , Glomerulonephritis/immunology , Graft Survival , Hospitals, University , Humans , Kaplan-Meier Estimate , Kidney Transplantation/adverse effects , Male , Middle Aged , Multivariate Analysis , Netherlands , Predictive Value of Tests , Proportional Hazards Models , Recurrence , Registries , Retrospective Studies , Risk Factors , Time Factors , Treatment Outcome
15.
Am J Pathol ; 185(8): 2132-42, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26216283

ABSTRACT

We have identified platelet-derived growth factor (PDGF)-CC as a potent profibrotic mediator in kidney fibrosis and pro-angiogenic mediator in glomeruli. Because renal fibrosis is associated with progressive capillary rarefaction, we asked whether PDGF-CC neutralization in fibrosis might have detrimental anti-angiogenic effects leading to aggravated peritubular capillary loss. We analyzed capillary rarefaction in mice with and without PDGF-CC neutralization (using genetically deficient mice and neutralizing antibodies), in three different models of renal interstitial fibrosis, unilateral ureteral obstruction, unilateral ischemia-reperfusion, Col4a3-deficient (Alport) mice, and healthy animals. Independent of the effect of PDGF-CC neutralization on renal fibrosis, we found no difference in capillary rarefaction between PDGF-CC-neutralized mice and mice with intact PDGF-CC. We also found no differences in microvascular leakage (determined by extravasation of Evans Blue Dye) and in renal relative blood volume quantified using in vivo microcomputed tomography. PDGF-CC neutralization had no effects on renal microvasculature in healthy animals. Capillary endothelium did not express PDGF receptor-α, suggesting that potential PDGF-CC effects would have to be indirect. PDGF-CC neutralization or deficiency was not associated with preservation or accelerated loss of peritubular capillaries, suggesting no significant pro-angiogenic effects of PDGF-CC during renal fibrosis. From a clinical perspective, the profibrotic effects of PDGF-CC outweigh the pro-angiogenic effects and, thus, do not limit a potential therapeutic use of PDGF-CC inhibition in renal fibrosis.


Subject(s)
Capillaries/metabolism , Kidney Diseases/metabolism , Kidney/metabolism , Lymphokines/metabolism , Platelet-Derived Growth Factor/metabolism , Animals , Capillaries/pathology , Disease Models, Animal , Fibrosis/metabolism , Fibrosis/pathology , Kidney/pathology , Kidney Diseases/pathology , Kidney Glomerulus/metabolism , Kidney Glomerulus/pathology , Lymphokines/genetics , Mice , Mice, Knockout , Platelet-Derived Growth Factor/genetics , Ureteral Obstruction/metabolism , Ureteral Obstruction/pathology
16.
Am J Physiol Renal Physiol ; 306(10): F1179-89, 2014 May 15.
Article in English | MEDLINE | ID: mdl-24694588

ABSTRACT

Dual renin-angiotensin system (RAS) blockade in diabetic nephropathy is no longer feasible because of the profit/side effect imbalance. (Pro)renin receptor [(P)RR] blockade with handle region peptide (HRP) has been reported to exert beneficial effects in various diabetic models in a RAS-independent manner. To what degree (P)RR blockade adds benefits on top of RAS blockade is still unknown. In the present study, we treated diabetic TGR(mREN2)27 rats, a well-established nephropathy model with high prorenin levels [allowing continuous (P)RR stimulation in vivo], with HRP on top of renin inhibition with aliskiren. Aliskiren alone lowered blood pressure and exerted renoprotective effects, as evidenced by reduced glomerulosclerosis, diuresis, proteinuria, albuminuria, and urinary aldosterone levels as well as diminished renal (P)RR and ANG II type 1 receptor expression. It also suppressed plasma and tissue RAS activity and suppressed cardiac atrial natriuretic peptide and brain natriuretic peptide expression. HRP, when given on top of aliskiren, did not alter the effects of renin inhibition on blood pressure, RAS activity, or aldosterone. However, it counteracted the beneficial effects of aliskiren in the kidney, induced hyperkalemia, and increased plasma plasminogen activator-inhibitor 1, renal cyclooxygenase-2, and cardiac collagen content. All these effects have been linked to (P)RR stimulation, suggesting that HRP might, in fact, act as a partial agonist. Therefore, the use of HRP on top of RAS blockade in diabetic nephropathy is not advisable.


Subject(s)
Amides/pharmacology , Diabetes Mellitus, Experimental/physiopathology , Fumarates/pharmacology , Kidney/drug effects , Kidney/physiopathology , Oligopeptides/pharmacology , Receptors, Cell Surface/antagonists & inhibitors , Renin/genetics , Aldosterone/metabolism , Animals , Blood Pressure/drug effects , Blood Pressure/physiology , Cyclooxygenase 2/metabolism , Diabetes Mellitus, Experimental/chemically induced , Disease Models, Animal , Female , Male , Plasminogen Activator Inhibitor 1/metabolism , Potassium/metabolism , Rats , Rats, Sprague-Dawley , Rats, Transgenic , Receptors, Cell Surface/drug effects , Renin-Angiotensin System/drug effects , Renin-Angiotensin System/physiology , Streptozocin/adverse effects , Prorenin Receptor
17.
Int J Cancer ; 134(9): 2108-17, 2014 May 01.
Article in English | MEDLINE | ID: mdl-24127203

ABSTRACT

Human papillomavirus (HPV) is a risk factor for the development of benign and malignant mucosal head and neck lesions. P16(INK4A) is often used as a surrogate marker for HPV-infection, although there is still controversy with respect its reliability. Our aim was to determine if p16(INK4A) overexpression can accurately predict both high-risk and low-risk-HPV-presence in (pre)malignant and benign head and neck lesions. P16(INK4A) immunohistochemistry was performed on paraffin-embedded tissue sections of 162 oropharyngeal squamous cell carcinomas (OPSCC), 14 tonsillar and 23 laryngeal dysplasias, and 20 tonsillar and 27 laryngeal papillomas. PCR, enzyme-immunoassay and FISH analysis were used to assess HPV-presence and type. Of the 162 OPSCC and 14 tonsillar dysplasias, 51 (31%) and 10 (71%) were HPV16-positive, respectively. All tonsillar papillomas were HPV-negative and four laryngeal dysplasias and 26 laryngeal papillomas were positive for HPV6 or -11. P16(INK4A) immunohistochemistry revealed a strong nuclear and cytoplasmic staining in 50 out of 51 HPV16-positive and 5 out of 111 HPV-negative OPSCC (p < 0.0001) and in all HPV16-positive tonsillar dysplasias, whereas highly variable staining patterns were detected in the papillomas and laryngeal dysplasias, irrespective of the HPV-status. In addition, the latter lesions generally showed a higher nuclear than cytoplasmic p16(INK4A) immunostaining intensity. In conclusion, our data show that strong nuclear and cytoplasmic p16(INK4A) overexpression is a reliable surrogate indicator for HPV16 in OPSCC and (adjacent) dysplasias. For HPV6 or -11-positive and HPV-negative benign and premalignant lesions of the tonsil and larynx, however, p16(INK4A) immunostaining is highly variable and cannot be recommended to predict HPV-presence.


Subject(s)
Carcinoma, Squamous Cell/virology , Cyclin-Dependent Kinase Inhibitor p16/metabolism , Head and Neck Neoplasms/virology , Oropharyngeal Neoplasms/virology , Papilloma/virology , Papillomavirus Infections/diagnosis , Precancerous Conditions/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Biomarkers, Tumor/analysis , Carcinoma, Squamous Cell/metabolism , Child , Child, Preschool , Female , Head and Neck Neoplasms/metabolism , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Infant , Laryngeal Neoplasms/metabolism , Laryngeal Neoplasms/virology , Male , Middle Aged , Oropharyngeal Neoplasms/metabolism , Papilloma/metabolism , Papillomavirus Infections/complications , Precancerous Conditions/metabolism , Precancerous Conditions/virology , Risk Factors , Squamous Cell Carcinoma of Head and Neck , Young Adult
18.
Diabetologia ; 57(1): 224-35, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24162587

ABSTRACT

AIMS/HYPOTHESIS: In diabetes, advanced glycation end-products (AGEs) and the AGE precursor methylglyoxal (MGO) are associated with endothelial dysfunction and the development of microvascular complications. In this study we used a rat model of diabetes, in which rats transgenically overexpressed the MGO-detoxifying enzyme glyoxalase-I (GLO-I), to determine the impact of intracellular glycation on vascular function and the development of early renal changes in diabetes. METHODS: Wild-type and Glo1-overexpressing rats were rendered diabetic for a period of 24 weeks by intravenous injection of streptozotocin. Mesenteric arteries were isolated to study ex vivo vascular reactivity with a wire myograph and kidneys were processed for histological examination. Glycation was determined by mass spectrometry and immunohistochemistry. Markers for inflammation, endothelium dysfunction and renal dysfunction were measured with ELISA-based techniques. RESULTS: Diabetes-induced formation of AGEs in mesenteric arteries and endothelial dysfunction were reduced by Glo1 overexpression. Despite the absence of advanced nephrotic lesions, early markers of renal dysfunction (i.e. increased glomerular volume, decreased podocyte number and diabetes-induced elevation of urinary markers albumin, osteopontin, kidney-inflammation-molecule-1 and nephrin) were attenuated by Glo1 overexpression. In line with this, downregulation of Glo1 in cultured endothelial cells resulted in increased expression of inflammation and endothelium dysfunction markers. In fully differentiated cultured podocytes incubation with MGO resulted in apoptosis. CONCLUSIONS/INTERPRETATION: This study shows that effective regulation of the GLO-I enzyme is important in the prevention of vascular intracellular glycation, endothelial dysfunction and early renal impairment in experimental diabetes. Modulating the GLO-I pathway therefore may provide a novel approach to prevent vascular complications in diabetes.


Subject(s)
Diabetes Mellitus/metabolism , Lactoylglutathione Lyase/metabolism , Animals , Immunohistochemistry , Lactoylglutathione Lyase/genetics , Male , Pyruvaldehyde/metabolism , Rats , Rats, Transgenic
19.
J Voice ; 27(3): 376-80, 2013 May.
Article in English | MEDLINE | ID: mdl-23490124

ABSTRACT

OBJECTIVES: The human female voice changes in quality during the menstrual cycle and during pregnancy and menopause. The underlying pathophysiological mechanisms are as yet not known. The aim of this study, therefore, was to evaluate the existence of estrogen receptors (ERs) and progesterone receptors (PRs) in the human vocal fold. MATERIAL AND METHODS: Biopsies of benign vocal fold lesions from 37 female patients were obtained during surgery. Immunohistochemistry for expression of ERs and PRs was performed and evaluated on a semiquantitative scale by two independent pathologists. RESULTS: In series 1, immunohistochemical staining showed six sections positive for ER and three sections for PR. One section had positive staining for both receptors. In series 2, immunohistochemical staining showed 10 of the 15 edema biopsies were positive for ER and six for PR. Six biopsies expressed both receptors. Four of the 10 laryngocele biopsies were positive for ER and two for PR. One was positive for both receptors. CONCLUSION: Our study demonstrates that ERs and PRs are expressed in the larynx of the female human vocal fold in conjunction with edema. The function of these receptors has to be elucidated in future studies.


Subject(s)
Receptors, Estrogen/analysis , Receptors, Progesterone/analysis , Vocal Cords/chemistry , Adolescent , Adult , Aged , Biopsy , Female , Humans , Immunohistochemistry , Middle Aged , Vocal Cords/pathology , Vocal Cords/surgery , Young Adult
20.
PLoS One ; 8(2): e57815, 2013.
Article in English | MEDLINE | ID: mdl-23469072

ABSTRACT

Transient activation of the renin-angiotensin system (RAS) induces irreversible renal damage causing sustained elevation in blood pressure (BP) in Cyp1a1-Ren2 transgenic rats. In our current study we hypothesized that activation of the AT1-receptor (AT1R) leads to a T-cell response causing irreversible impairment of renal function and hypertension. Cyp1a1-Ren2 rats harbor a construct for activation of the RAS by indole-3-carbinol (I3C). Rats were fed a I3C diet between 4-8 weeks of age to induce hypertension. Next, I3C was withdrawn and rats were followed-up for another 12 weeks. Additional groups received losartan (20 mg/kg/day) or hydralazine (100 mg/kg/day) treatment between 4-8 weeks. Rats were placed for 24h in metabolic cages before determining BP at week 8, 12 and 20. At these ages, subsets of animals were sacrificed and the presence of kidney T-cell subpopulations was investigated by immunohistochemistry and molecular marker analysis. The development of sustained hypertension was completely prevented by losartan, whereas hydralazine only caused a partial decrease in BP. Markers of renal damage: KIM-1 and osteopontin were highly expressed in urine and kidney samples of I3C-treated rats, even until 20 weeks of age. Additionally, renal expression of regulatory-T cells (Tregs) was highly increased in I3C-treated rats, whereas the expression of T-helper 1 (Th1) cells demonstrated a strong decrease. Losartan prevented these effects completely, whereas hydralazine was unable to affect these changes. In young Cyp1a1-Ren2 rats AT1R activation leads to induction of an immune response, causing a shift from Th1-cells to Tregs, contributing to the development of irreversible renal damage and hypertension.


Subject(s)
Kidney/pathology , Kidney/physiopathology , Receptor, Angiotensin, Type 1/metabolism , Renin-Angiotensin System/immunology , Animals , Biomarkers/metabolism , Hemodynamics/drug effects , Hydralazine/pharmacology , Hypertension/immunology , Hypertension/metabolism , Hypertension/pathology , Hypertension/physiopathology , Kidney/drug effects , Kidney/metabolism , Losartan/pharmacology , Rats , Rats, Transgenic , Renin-Angiotensin System/drug effects , T-Lymphocytes/drug effects , T-Lymphocytes/immunology , Time Factors
SELECTION OF CITATIONS
SEARCH DETAIL