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1.
Hemodial Int ; 25(4): 498-506, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34085391

RESUMO

INTRODUCTION: Hydrophilic modification with polyvinylpyrrolidone (PVP) increases the biocompatibility profile of synthetic dialysis membranes. However, PVP may be eluted into the patient's blood, which has been discussed as a possible cause for adverse reactions rarely occurring with synthetic membranes. We investigated the content of PVP and its elution from the blood-side surface from commercially available dialyzers, including the novel FX CorAL, with PVP-enriched and α-tocopherol-stabilized membrane, and link the results to the level of platelet loss during dialysis as a maker of biocompatibility. METHODS: Six synthetic, PVP containing, dialyzers (FX CorAL, FX CorDiax [Fresenius Medical Care]; Polyflux, THERANOVA [Baxter]; ELISIO [Nipro]; xevonta [B. Braun]) were investigated in the present study. The content of PVP on blood-side surface was determined with X-ray photoelectron spectroscopy (XPS). The amount of elutable PVP was measured photometrically after 5 h recirculation. The level of platelet loss was evaluated in an ex vivo recirculation model with human blood. FINDINGS: Highest PVP content on the blood-side surface was found for the polysulfone-based FX CorAL (26.3%), while the polyethersulfone-based THERANOVA (15.6%) had the lowest PVP content. Elution of PVP was highest for the autoclave steam-sterilized THERANOVA (9.1 mg/1.6 m2 dialyzer) and Polyflux (9.0 mg/1.6 m2 dialyzer), while the lowest PVP elution was found for the INLINE steam sterilized FX CorAL and FX CorDiax (<0.5 mg/1.6 m2 dialyzer, for both). Highest platelet loss was found for xevonta (+164.4% compared to the reference) and the lowest for the FX CorAL (-225.2%) among the polysulfone-based dialyzers; among the polyethersulfone-based dialyzers, THERANOVA (+95.5%) had the highest and ELISIO (-52.1%) the lowest platelet loss. DISCUSSION: Polyvinylpyrrolidone content and elution differ between commercially available dialyzers and were found to be linked to the membrane material and sterilization method. The amount of non-eluted PVP on the blood-side surface may be an important determinant for the biocompatibility of dialyzers.


Assuntos
Povidona , Diálise Renal , Humanos , Membranas Artificiais , Esterilização
2.
PLoS One ; 14(2): e0212795, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30794672

RESUMO

BACKGROUND: Anemia is a major comorbidity of patients with end-stage renal disease and poses an enormous economic burden to health-care systems. High dose erythropoiesis-stimulating agents (ESAs) have been associated with unfavorable clinical outcomes. We explored whether mixed-dilution hemodiafiltration (Mixed-HDF), based on its innovative substitution modality, may improve anemia outcomes compared to the traditional post-dilution hemodiafiltration (Post-HDF). METHODS: We included 174 adult prevalent dialysis patients (87 on Mixed-HDF, 87 on Post-HDF) treated in 24 NephroCare dialysis centers between January 2010 and August 2016 into this retrospective cohort study. All patients were dialyzed three times per week and had fistula/graft as vascular access. Patients were matched at baseline and followed over a one-year period. The courses of hemoglobin levels (Hb) and monthly ESA consumption were compared between the two groups with linear mixed models. RESULTS: Mean baseline Hb was 11.9±1.3 and 11.8±1.1g/dl in patients on Mixed- and Post-HDF, respectively. While Hb remained stable in patients on Mixed-HDF, it decreased slightly in patients on Post-HDF (at month 12: 11.8±1.2 vs 11.1±1.2g/dl). This tendency was confirmed by our linear mixed model (p = 0.0514 for treatment x time interaction). Baseline median ESA consumption was 6000 [Q1:0;Q3:16000] IU/4 weeks in both groups. Throughout the observation period ESA doses tended to be lower in the Mixed-HDF group (4000 [Q1:0;Q3:16000] vs 8000 [Q1:0;Q3:20000] IU/4 weeks at month 12; p = 0.0791 for treatment x time interaction). Sensitivity analyses, adjusting for differences not covered by matching at baseline, strengthened our results (Hb: p = 0.0124; ESA: p = 0.0687). CONCLUSIONS: Results of our explorative study suggest that patients on Mixed-HDF may have clinical benefits in terms of anemia management. This may also have a beneficial economic impact. Future studies are needed to confirm our hypothesis-generating results and to provide additional evidence on the potential beneficial effects of Mixed-HDF.


Assuntos
Anemia , Hematínicos/administração & dosagem , Hemodiafiltração , Falência Renal Crônica , Modelos Biológicos , Adulto , Idoso , Anemia/sangue , Anemia/complicações , Anemia/terapia , Feminino , Seguimentos , Hemoglobinas/metabolismo , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
3.
J Exp Orthop ; 3(1): 16, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27473203

RESUMO

BACKGROUND: Application of genetically modified bone marrow concentrates in articular cartilage lesions is a promising approach to enhance cartilage repair by stimulating the chondrogenic differentiation processes in sites of injury. METHOD: In the present study, we examined the potential benefits of transferring the proliferative and pro-chondrogenic basic fibroblast growth factor (FGF-2) to human bone marrow aspirates in vitro using the clinically adapted recombinant adeno-associated virus (rAAV) vectors to monitor the biological and chondrogenic responses over time to the treatment compared with control (lacZ) gene application. RESULTS: Effective, significant FGF-2 gene transfer and expression via rAAV was established in the aspirates relative to the lacZ condition (from ~ 97 to 36 pg rhFGF-2/mg total proteins over an extended period of 21 days). Administration of the candidate FGF-2 vector led to prolonged increases in cell proliferation, matrix synthesis, and chondrogenesis but also to hypertrophic and terminal differentiation in the aspirates. CONCLUSION: The present evaluation shows the advantages of rAAV-mediated FGF-2 gene transfer to conveniently modify bone marrow concentrates as a future approach to directly treat articular cartilage lesions, provided that expression of the growth factor is tightly regulated to prevent premature hypertrophy in vivo.

4.
Nephrol Dial Transplant ; 31(11): 1835-1845, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27190361

RESUMO

BACKGROUND: Treatment of iron deficiency with intravenous (i.v.) iron is a first-line strategy to improve anaemia of chronic kidney disease. Previous in vitro experiments demonstrated that different i.v. iron preparations inhibit differentiation of haematopoietic stem cells to monocytes, but their effect on monocyte differentiation to macrophages and mature dendritic cells (mDCs) has not been assessed. We investigated substance-specific effects of iron sucrose (IS), sodium ferric gluconate (SFG), ferric carboxymaltose (FCM) and iron isomaltoside 1000 (IIM) on monocytic differentiation to M1/M2 macrophages and mDCs. METHODS: Via flow cytometry and microRNA (miRNA) expression analysis, we morphologically and functionally characterized monocyte differentiation to M1/M2 macrophages and mDCs after monocyte stimulation with IS, SFG, FCM and IIM (0.133, 0.266 and 0.533 mg/mL, respectively). To assess potential clinical implications, we compared monocytic phagocytosis capacity in dialysis patients who received either 500 mg IS or IIM. RESULTS: Phenotypically, IS and SFG dysregulated the expression of macrophage (e.g. CD40, CD163) and mDC (e.g. CD1c, CD141) surface markers. Functionally, IS and SFG impaired macrophage phagocytosis capacity. Phenotypic and functional alterations were less pronounced with FCM, and virtually absent with IIM. In miRNA expression analysis of mDCs, IS dysregulated miRNAs such as miR-146b-5p and miR-155-5p, which are linked to Toll-like receptor and mitogen-activated protein kinase signalling pathways. In vivo, IS reduced monocytic phagocytosis capacity within 1 h after infusion, while IIM did not. CONCLUSIONS: This study demonstrates that less stable i.v. iron preparations specifically affect monocyte differentiation towards macrophages and mDCs.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Diferenciação Celular/efeitos dos fármacos , Células Dendríticas/citologia , Compostos de Ferro/administração & dosagem , Macrófagos/citologia , Monócitos/citologia , Anemia Ferropriva/imunologia , Anemia Ferropriva/patologia , Estudos de Casos e Controles , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Dissacarídeos/administração & dosagem , Dissacarídeos/farmacologia , Compostos Férricos/administração & dosagem , Compostos Férricos/farmacologia , Óxido de Ferro Sacarado , Ácido Glucárico/administração & dosagem , Ácido Glucárico/farmacologia , Hematínicos/administração & dosagem , Hematínicos/farmacologia , Humanos , Injeções Intravenosas , Compostos de Ferro/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Maltose/administração & dosagem , Maltose/análogos & derivados , Maltose/farmacologia , MicroRNAs/genética , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Fagocitose/efeitos dos fármacos
5.
Medicine (Baltimore) ; 95(18): e3466, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27149446

RESUMO

In experimental myocardial infarction (MI), a rise in cell counts of circulating monocyte subsets contributes to impaired myocardial healing and to atherosclerotic plaque destabilization. In humans, the prognostic role of monocyte subsets in patients suffering ST-elevation MI (STEMI) is still unclear. In the present study, we aimed to determine the kinetics of the 3 monocyte subsets (classical CD14++CD16-, intermediate CD14++CD16+, and nonclassical CD14+CD16++ monocytes), as well as the subset-specific monocyte-platelet aggregates (MPA), in acute STEMI followed by primary percutaneous coronary intervention (PCI), and their relationships with cardiovascular outcomes during a 2-year follow-up.Monocyte subsets and MPA were measured in 100 STEMI patients receiving primary PCI on days 1, 2, 3, 5, and 7 of symptom onset, which were compared with 60 stable coronary heart disease patients and 35 healthy volunteers. From day 1 to day 7, significant increases in the counts of CD14++CD16+ monocytes and CD14++CD16+ MPA were observed, with peak levels on day 2. During a median follow-up of 2.0 years, 28 first cardiovascular events (defined as cardiovascular death, nonfatal ischemic stroke, recurrent MI, need for emergency or repeat revascularization, and rehospitalization for heart failure) were recorded. After adjustment for confounders, CD14++CD16+ monocytosis (day 1 [HR: 3.428; 95% CI: 1.597-7.358; P = 0.002], day 2 [HR: 4.835; 95% CI: 1.106-21.13; P = 0.04], day 3 [HR: 2.734; 95% CI: 1.138-6.564; P = 0.02], and day 7 [HR: 2.647; 95% CI: 1.196-5.861; P = 0.02]), as well as increased levels of CD14++CD16+ MPA measured on all time points (days 1, 2, 3, 5, and 7), had predictive values for adverse cardiovascular events.In conclusion, our data show the expansion of the CD14++CD16+ monocyte subset during acute phase of STEMI has predictive values for 2-year adverse cardiovascular outcomes in patients treated with primary PCI. Future studies will be warranted to elucidate whether CD14++CD16+ monocytes may become a target cell population for new therapeutic strategies after STEMI.


Assuntos
Antígenos CD/análise , Plaquetas/metabolismo , Monócitos , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Idoso , Agregação Celular , China , Angiografia Coronária/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/classificação , Monócitos/metabolismo , Readmissão do Paciente/estatística & dados numéricos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Período Pós-Operatório , Valor Preditivo dos Testes , Recidiva , Reoperação/estatística & dados numéricos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia
6.
Epigenetics ; 11(4): 259-72, 2016 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-27018948

RESUMO

Human monocytes are a heterogeneous cell population consisting of 3 subsets: classical CD14++CD16-, intermediate CD14++CD16+ and nonclassical CD14+CD16++ monocytes. Via poorly characterized mechanisms, intermediate monocyte counts rise in chronic inflammatory diseases, among which chronic kidney disease is of particular epidemiologic importance. DNA methylation is a central epigenetic feature that controls hematopoiesis. By applying next-generation Methyl-Sequencing we now tested how far the 3 monocyte subsets differ in their DNA methylome and whether uremia induces DNA methylation changes in differentiating monocytes. We found that each monocyte subset displays a unique phenotype with regards to DNA methylation. Genes with differentially methylated promoter regions in intermediate monocytes were linked to distinct immunological processes, which is in line with results from recent gene expression analyses. In vitro, uremia induced dysregulation of DNA methylation in differentiating monocytes, which affected several transcription regulators important for monocyte differentiation (e.g., FLT3, HDAC1, MNT) and led to enhanced generation of intermediate monocytes. As potential mediator, the uremic toxin and methylation inhibitor S-adenosylhomocysteine induced shifts in monocyte subsets in vitro, and associated with monocyte subset counts in vivo. Our data support the concept of monocyte trichotomy and the distinct role of intermediate monocytes in human immunity. The shift in monocyte subsets that occurs in chronic kidney disease, a proinflammatory condition of substantial epidemiological impact, may be induced by accumulation of uremic toxins that mediate epigenetic dysregulation.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Metilação de DNA/genética , Histona Desacetilase 1/genética , Insuficiência Renal Crônica/genética , Proteínas Repressoras/genética , Uremia/genética , Tirosina Quinase 3 Semelhante a fms/genética , Diferenciação Celular/genética , Proteínas Ligadas por GPI/genética , Regulação da Expressão Gênica , Voluntários Saudáveis , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Receptores de Lipopolissacarídeos/genética , Monócitos/metabolismo , Receptores de IgG/genética , Insuficiência Renal Crônica/patologia , S-Adenosil-Homocisteína/metabolismo , Uremia/patologia
7.
Blood ; 126(24): 2601-10, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26443621

RESUMO

Human monocytes are subdivided into classical, intermediate, and nonclassical subsets, but there is no unequivocal strategy to dissect the latter 2 cell types. We show herein that the cell surface marker 6-sulfo LacNAc (slan) can define slan-positive CD14(+)CD16(++) nonclassical monocytes and slan-negative CD14(++)CD16(+) intermediate monocytes. Gene expression profiling confirms that slan-negative intermediate monocytes show highest expression levels of major histocompatibility complex class II genes, whereas a differential ubiquitin signature is a novel feature of the slan approach. In unsupervised hierarchical clustering, the slan-positive nonclassical monocytes cluster with monocytes and are clearly distinct from CD1c(+) dendritic cells. In clinical studies, we show a selective increase of the slan-negative intermediate monocytes to >100 cells per microliter in patients with sarcoidosis and a fivefold depletion of the slan-positive monocytes in patients with hereditary diffuse leukoencephalopathy with axonal spheroids (HDLS), which is caused by macrophage colony-stimulating factor (M-CSF) receptor mutations. These data demonstrate that the slan-based definition of CD16-positive monocyte subsets is informative in molecular studies and in clinical settings.


Assuntos
Amino Açúcares/análise , Monócitos/classificação , Receptor de Fator Estimulador de Colônias de Macrófagos/genética , Receptores de IgG/análise , Antígenos CD1/análise , Células Dendríticas/química , Feminino , Citometria de Fluxo , Proteínas Ligadas por GPI/análise , Perfilação da Expressão Gênica , Genes MHC da Classe II , Estudo de Associação Genômica Ampla , Glicoproteínas/análise , Antígenos HLA-D/análise , Humanos , Separação Imunomagnética , Leucoencefalopatias/genética , Leucoencefalopatias/imunologia , Leucoencefalopatias/patologia , Receptores de Lipopolissacarídeos/análise , Masculino , Pessoa de Meia-Idade , Monócitos/química , Monócitos/imunologia , Mutação Puntual , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sarcoidose/imunologia , Sarcoidose/patologia , Adulto Jovem
8.
Nephrol Dial Transplant ; 30(1): 143-53, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25313167

RESUMO

BACKGROUND: Monocytes are critical in innate immunity and transplantation. Three monocyte subsets exist, CD14(++)CD16(-), CD14(++)CD16(+) and CD14(+)CD16(++) monocytes; cell counts of CD14(++)CD16(+) and CD14(+)CD16(++) monocytes are increased in pre-transplant chronic kidney disease. Interestingly, the effect of immunosuppressants on monocyte heterogeneity has not been well studied. METHODS: The impact of immunosuppressants on monocyte subsets was studied: (i) in 152 kidney transplant (KTx) recipients to characterize subset distribution in the steady state, (ii) in patients after autologous (n = 10) versus allogenic (n = 9) haematopoietic stem cell transplantation (HSCT) to analyse monocyte subset development and (iii) in an in vitro model to compare the effect of immunosuppressants on monocyte subset biology. RESULTS: In KTx, steroid intake was associated with higher total, CD14(++)CD16(-) and CD14(++)CD16(+) monocyte counts, but fewer CD14(+)CD16(++) monocytes, whereas intake of mycophenolate, calcineurin inhibitors (CNI) and mammalian target of rapamycin inhibitors (mTORI) did not affect monocyte (subset) counts. In linear regression analysis, only steroid intake was a significant determinant of monocyte (subset) counts: total monocytes (ß = 0.331; P < 0.001), CD14(++)CD16(-) monocytes (ß = 0.374; P < 0.001), CD14(++)CD16(+) monocytes (ß = 0.221; P = 0.010) and CD14(+)CD16(++) monocytes (ß = -0.169; P = 0.049). After HSCT, CD14(++)CD16(-) monocytes were the first to arise, followed by CD14(++)CD16(+) and later by CD14(+)CD16(++) monocytes. Monocyte subset distribution did not differ significantly in patients after allogenic compared with autologous transplantation. CNI, mycophenolate and methotrexate did not influence monocyte subset development, but modified surface receptor expression (CCR2, HLA-DR, ENG, TEK and TLR4) in allogenic HSCT. CONCLUSION: Chronic low-dose steroids are associated with monocytosis and higher counts of CD14(++)CD16(-) and of proinflammatory CD14(++)CD16(+) monocytes.


Assuntos
Antígenos CD/metabolismo , Imunossupressores/uso terapêutico , Monócitos/classificação , Monócitos/efeitos dos fármacos , Receptores de Superfície Celular/metabolismo , Insuficiência Renal Crônica/terapia , Células Cultivadas , Terapia Combinada , Feminino , Citometria de Fluxo , Regulação da Expressão Gênica , Transplante de Células-Tronco Hematopoéticas , Humanos , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Insuficiência Renal Crônica/metabolismo , Transplante Autólogo , Transplante Homólogo
9.
Arterioscler Thromb Vasc Biol ; 34(9): 2120-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25060791

RESUMO

OBJECTIVE: Patients with chronic kidney disease (CKD) display impaired cholesterol efflux capacity and elevated CD14(++)CD16(+) monocyte counts. In mice, dysfunctional cholesterol efflux causes monocytosis. It is unknown whether cholesterol efflux capacity and monocyte subsets are associated in CKD. APPROACH AND RESULTS: In 438 patients with CKD, mediators of cholesterol efflux capacity (high-density lipoprotein cholesterol/apolipoprotein A-I) and monocyte subsets were analyzed as predictors of cardiovascular events. Monocyte subset-specific intracellular lipid content, CD36, CD68, and ABCA1 were measured in a subgroup. Experimentally, we analyzed subset-specific cholesterol efflux capacity and response to oxidized low-density lipoprotein cholesterol stimulation in CKD. Epidemiologically, both low Apo-I and low high-density lipoprotein cholesterol were associated with high CD14(++)CD16(+) monocyte counts in linear regression analyses (apolipoprotein A-I: ß=-0.171; P<0.001; high-density lipoprotein cholesterol: ß=-0.138; P=0.005), but not with counts of other monocyte subsets. In contrast to apolipoprotein A-I or high-density lipoprotein cholesterol, higher CD14(++)CD16(+) monocyte counts independently predicted cardiovascular events (hazard ratio per increase of 1 cell/µL: 1.011 [1.003-1.020]; P=0.007). Experimentally, CD14(++)CD16(+) monocytes demonstrated preferential lipid accumulation, high CD36, CD68, and low ABCA1 expression and, consequently, displayed low cholesterol efflux capacity, avid oxidized low-density lipoprotein cholesterol uptake, and potent intracellular interleukin-6, interleukin-1ß, and tumor necrosis factor-α production. CONCLUSIONS: Taken together, mediators of cholesterol efflux are associated with CD14(++)CD16(+) monocyte counts, which independently predict adverse outcome in CKD.


Assuntos
Apolipoproteína A-I/análise , Doenças Cardiovasculares/epidemiologia , HDL-Colesterol/sangue , Monócitos , Insuficiência Renal Crônica/sangue , Transportador 1 de Cassete de Ligação de ATP/sangue , Idoso , Doenças Cardiovasculares/etiologia , Feminino , Proteínas Ligadas por GPI/análise , Humanos , Imunofenotipagem , Interleucina-1beta/sangue , Interleucina-6/biossíntese , Interleucina-6/sangue , Contagem de Leucócitos , Lipídeos/sangue , Receptores de Lipopolissacarídeos/análise , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Monócitos/classificação , Estudos Prospectivos , Receptores de IgG/análise , Insuficiência Renal Crônica/complicações , Método Simples-Cego , Fator de Necrose Tumoral alfa/análise
10.
Artigo em Inglês | MEDLINE | ID: mdl-25052703

RESUMO

Alternative polyadenylation (APA) is a widespread mechanism that contributes to the sophisticated dynamics of gene regulation. Approximately 50% of all protein-coding human genes harbor multiple polyadenylation (PA) sites; their selective and combinatorial use gives rise to transcript variants with differing length of their 3' untranslated region (3'UTR). Shortened variants escape UTR-mediated regulation by microRNAs (miRNAs), especially in cancer, where global 3'UTR shortening accelerates disease progression, dedifferentiation and proliferation. Here we present APADB, a database of vertebrate PA sites determined by 3' end sequencing, using massive analysis of complementary DNA ends. APADB provides (A)PA sites for coding and non-coding transcripts of human, mouse and chicken genes. For human and mouse, several tissue types, including different cancer specimens, are available. APADB records the loss of predicted miRNA binding sites and visualizes next-generation sequencing reads that support each PA site in a genome browser. The database tables can either be browsed according to organism and tissue or alternatively searched for a gene of interest. APADB is the largest database of APA in human, chicken and mouse. The stored information provides experimental evidence for thousands of PA sites and APA events. APADB combines 3' end sequencing data with prediction algorithms of miRNA binding sites, allowing to further improve prediction algorithms. Current databases lack correct information about 3'UTR lengths, especially for chicken, and APADB provides necessary information to close this gap. Database URL: http://tools.genxpro.net/apadb/.


Assuntos
Biologia Computacional/métodos , Bases de Dados Genéticas , MicroRNAs , Poliadenilação , Animais , Galinhas , Sistemas de Gerenciamento de Base de Dados , Humanos , Camundongos , Interface Usuário-Computador
11.
Atherosclerosis ; 234(1): 17-22, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24589563

RESUMO

OBJECTIVE: Although homocysteine has been proposed as a cardiovascular risk factor, interventional trials lowering homocysteine have not consistently demonstrated clinical benefit. Recent evidence proposed the homocysteine metabolite S-adenosylhomocysteine (SAH) rather than homocysteine itself as the real culprit in cardiovascular disease. Of note, SAH is predominantly excreted by the kidneys, and cannot be lowered by vitamin supplementation. Due to its cumbersome measurement, data from large studies on the association between SAH, kidney function and cardiovascular disease are not available. METHODS: We recruited 420 apparently healthy subjects into our I Like HOMe FU study. Among all study participants, we assessed parameters of C1 metabolism (homocysteine, SAH and S-adenosylmethionine), renal function (estimated glomerular filtration rate [eGFR]) and subclinical atherosclerosis (common carotid intima-media-thickness [IMT]). eGFR was estimated by the CKD-EPIcreat-cys equation. RESULTS: Traditional cardiovascular risk factors and subclinical atherosclerosis were associated with SAH, but not with homocysteine (IMT vs SAH: r = 0.129; p = 0.010; IMT vs homocysteine: r = 0.009; p = 0.853). Moreover, renal function was more closely correlated with SAH than with homocysteine (eGFR vs SAH: r = -0.335; p < 0.001; eGFR vs homocysteine: r = -0.250; p < 0.001). The association between eGFR and SAH remained significant after adjustment for traditional cardiovascular risk factors. CONCLUSION: In summary, cardiovascular risk factors, subclinical atherosclerosis and eGFR are more strongly associated with SAH than with homocysteine in apparently healthy subjects. Thus, SAH might represent a more promising target to prevent cardiovascular disease than homocysteine.


Assuntos
Aterosclerose/etiologia , Aterosclerose/fisiopatologia , S-Adenosil-Homocisteína/metabolismo , Doenças Assintomáticas , Aterosclerose/complicações , Aterosclerose/metabolismo , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Feminino , Taxa de Filtração Glomerular , Homocisteína/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , S-Adenosilmetionina/metabolismo
12.
Nephrol Dial Transplant ; 29(4): 809-22, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24523357

RESUMO

BACKGROUND: Iron deficiency contributes to anaemia in patients with chronic kidney disease. I.v. iron is therefore widely used for anaemia treatment, although it may induce oxidative stress and activate monocytes. Different i.v. iron preparations are available, but interestingly their substance-specific immunologic effects are poorly studied. METHODS: We analysed the effect of iron sucrose, ferric carboxymaltose, iron isomaltoside 1000, low-molecular-weight iron dextran and ferumoxytol on classical, intermediate and nonclassical monocyte biology. We therefore stimulated in vitro mature monocytes and haematopoietic CD34(+) stem cells during their differentiation into monocytes with different concentrations (0.133, 0.266, 0.533 mg/mL) of i.v. iron preparations. Alterations of monocyte subset distribution, expression of surface markers (CD86, CCR5, CX3CR1), as well as production of pro-inflammatory cytokines (TNF-α, IL-1ß) and reactive oxygen species were measured using flow cytometry. Additionally, we analysed phagocytosis and antigen presentation capacity. RESULTS: We found specific immunologic effects after stimulation with iron sucrose which were not induced by the other iron preparations. Iron sucrose activated monocyte subsets leading to significantly increased CD86 expression. Simultaneously CD16 and CX3CR1 expression and monocytic phagocytosis capacity were decreased. Additionally, differentiation of monocytes from haematopoietic CD34(+) stem cells was almost completely abolished after stimulation with iron sucrose. CONCLUSIONS: Our findings demonstrate that specific immunologic effects of distinct i.v. iron preparations exist. The clinical relevance of these findings requires further investigation.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Imunidade Celular , Compostos de Ferro/administração & dosagem , Monócitos/efeitos dos fármacos , Estresse Oxidativo/imunologia , Anemia Ferropriva/imunologia , Anemia Ferropriva/patologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Células Cultivadas , Quimiocinas/biossíntese , Quimiocinas/efeitos dos fármacos , Citometria de Fluxo , Humanos , Injeções Intravenosas , Monócitos/imunologia , Monócitos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Fagocitose/fisiologia
13.
Nephrol Dial Transplant ; 29(2): 348-55, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24166454

RESUMO

BACKGROUND: The recently introduced CKD-EPIcreat-cys equation surpassed creatinine-based equations for GFR estimation in a large cross-sectional analysis. However, its performance to predict individual risk of CKD progression and death in patients with various underlying CKD etiologies is unknown. METHODS: We recruited 444 patients with CKD GFR categories 2-4 (eGFR 15-89 mL/min/1.73 m2); baseline eGFR was estimated by the established MDRD and CKD-EPIcreat equations and by the novel CKD-EPIcreat-cys equation. RESULTS: Patients were followed for 2.7±1.2 years for the occurrence of the combined predefined endpoint event: death, need for renal replacement therapy or halving of eGFR. The endpoint occurred in 62 patients. Reclassification from MDRD determined categories to CKD-EPIcreat-cys categories yielded net reclassification improvements for those with the endpoint event (NRIevents) of 27.4% (95% CI: 16.7-40.0%) and for those without the event (NRInon-events) of -3.1% (-8.2 to 1.6%). Similarly, reclassification from CKD-EPIcreat categories to CKD-EPIcreat-cys categories yielded an NRIevents of 22.6% (10.2-34.3%) and NRInon-events of -11.3% (-15.9 to -6.5%). Addition of albuminuria to each eGFR equation increased the calculated risk of the outcome for a net 26-32% of those who subsequently reached the endpoint, and reduced the calculated risk in a net 21-23% in non-event patients, but only minimally. CONCLUSIONS: The CKD-EPIcreat-cys equation assigned patients who went on to have the event to more appropriate CKD risk categories than MDRD and CKD-EPIcreat, but patients without the event to less appropriate categories than CKD-EPIcreat. Addition of albuminuria marginally improved risk classification for those who had the event.


Assuntos
Doenças Cardiovasculares/epidemiologia , Comportamento Cooperativo , Creatinina/sangue , Cistatina C/sangue , Insuficiência Renal Crônica/epidemiologia , Medição de Risco/métodos , Idoso , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etiologia , Causas de Morte/tendências , Estudos Transversais , Feminino , Seguimentos , Taxa de Filtração Glomerular , Humanos , Masculino , Nova Zelândia/epidemiologia , Valor Preditivo dos Testes , Prognóstico , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/complicações , Fatores de Risco , Taxa de Sobrevida/tendências , Fatores de Tempo
14.
Circ Cardiovasc Genet ; 5(6): 611-20, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23074332

RESUMO

BACKGROUND: Accelerated atherosclerosis is a hallmark of chronic kidney disease (CKD). Although the role of epigenetic dysregulation in atherosclerosis is increasingly appreciated, only a few studies focused on epigenetics in CKD-associated cardiovascular disease, virtually all of which assessed epigenetic dysregulation globally. We hypothesized that gene-specific epigenetic dysregulation in CKD exists, affecting genes pertinent to inflammation and atherosclerosis. METHODS AND RESULTS: Ten clinically stable patients undergoing hemodialysis therapy and 10 healthy age- and sex-matched controls were recruited. Genome-wide analysis of DNA methylation was performed by SuperTAG methylation-specific digital karyotyping, in order to identify genes differentially methylated in CKD. Analysis of 27 043 436 tags revealed 4288 genomic loci with differential DNA methylation (P<10(-10)) between hemodialysis patients and control subjects. Annotation of UniTags to promoter databases allowed us to identify 52 candidate genes associated with cardiovascular disease and 97 candidate genes associated with immune/infection diseases. These candidate genes could be classified to distinct proatherogenic processes, including lipid metabolism and transport (eg, HMGCR, SREBF1, LRP5, EPHX2, and FDPS), cell proliferation and cell-cycle regulation (eg, MIK67, TP53, and ALOX12), angiogenesis (eg, ANGPT2, ADAMTS10, and FLT4), and inflammation (eg, TNFSF10, LY96, IFNGR1, HSPA1A, and IL12RB1). CONCLUSIONS: We provide a comprehensive analysis of genome-wide epigenetic alterations in CKD, identifying candidate genes associated with proatherogenic and inflammatory processes. These results may spur further research in the field of epigenetics in kidney disease and point to new therapeutic strategies in CKD-associated atherosclerotic disease.


Assuntos
Aterosclerose/genética , Metilação de DNA/genética , Epigênese Genética , Cariotipagem/métodos , Uremia/genética , Aterosclerose/sangue , Estudos de Casos e Controles , Bases de Dados Genéticas , Humanos , Masculino , Pessoa de Meia-Idade , Diálise Renal , Reprodutibilidade dos Testes , S-Adenosil-Homocisteína/sangue , S-Adenosilmetionina/sangue , Uremia/sangue
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