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1.
Int J Obes (Lond) ; 47(2): 126-137, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36509969

RESUMO

BACKGROUND: Obesity is a risk factor for adverse outcomes in COVID-19, potentially driven by chronic inflammatory state due to dysregulated secretion of adipokines and cytokines. We investigated the association between plasma adipokines and COVID-19 severity, systemic inflammation, clinical parameters, and outcome of COVID-19 patients. METHODS: In this multi-centre prospective cross-sectional study, we collected blood samples and clinical data from COVID-19 patients. The severity of COVID-19 was classified as mild (no hospital admission), severe (ward admission), and critical (ICU admission). ICU non-COVID-19 patients were also included and plasma from healthy age, sex, and BMI-matched individuals obtained from Lifelines. Multi-analyte profiling of plasma adipokines (Leptin, Adiponectin, Resistin, Visfatin) and inflammatory markers (IL-6, TNFα, IL-10) were determined using Luminex multiplex assays. RESULTS: Between March and December 2020, 260 SARS-CoV-2 infected individuals (age: 65 [56-74] BMI 27.0 [24.4-30.6]) were included: 30 mild, 159 severe, and 71 critical patients. Circulating leptin levels were reduced in critically ill patients with a high BMI yet this decrease was absent in patients that were administered dexamethasone. Visfatin levels were higher in critical COVID-19 patients compared to non-COVID-ICU, mild and severe patients (4.7 vs 3.4, 3.0, and 3.72 ng/mL respectively, p < 0.05). Lower Adiponectin levels, but higher Resistin levels were found in severe and critical patients, compared to those that did not require hospitalization (3.65, 2.7 vs 7.9 µg/mL, p < 0.001, and 18.2, 22.0 vs 11.0 ng/mL p < 0.001). CONCLUSION: Circulating adipokine levels are associated with COVID-19 hospitalization, i.e., the need for oxygen support (general ward), or the need for mechanical ventilation and other organ support in the ICU, but not mortality.


Assuntos
Adipocinas , COVID-19 , Humanos , Idoso , Leptina , Resistina , Nicotinamida Fosforribosiltransferase , Adiponectina , Estudos Transversais , Estudos Prospectivos , SARS-CoV-2 , Inflamação
2.
Rheumatology (Oxford) ; 61(7): 3060-3070, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34730794

RESUMO

OBJECTIVES: GCA is a large vessel vasculitis in which metabolically active immune cells play an important role. GCA diagnosis is based on CRP/ESR and temporal artery biopsies (TABs), in combination with 18F-fluorodeoxyglucose ([18F]FDG)-PET/CT relying on enhanced glucose uptake by glycolytic macrophages. Here, we studied circulating Pyruvate Kinase M2 (PKM2), a glycolytic enzyme, as a possible systemic marker of vessel wall inflammation in GCA. METHODS: Immunohistochemical detection of PKM2 was performed on inflamed (n = 12) and non-inflamed (n = 4) TABs from GCA patients and non-GCA (n = 9) patients. Dimeric PKM2 levels were assessed in plasma of GCA patients (n = 44), age-matched healthy controls (n = 41), metastatic melanoma patients (n = 7) and infection controls (n = 11). CRP, ESR and macrophage markers calprotectin and YKL-40 were correlated with plasma PKM2 levels. To detect the cellular source of plasma PKM2 in tissue, double IF staining was performed on inflamed GCA TABs. [18F]FDG-PET scans of 23 GCA patients were analysed and maximum standard uptake values and target to background ratios were calculated. RESULTS: PKM2 is abundantly expressed in TABs of GCA patients. Dimeric PKM2 plasma levels were elevated in GCA and correlated with CRP, ESR, calprotectin and YKL-40 levels. Elevated plasma PKM2 levels were downmodulated by glucocorticoid treatment. PKM2 was detected in both macrophages and T cells at the site of vascular inflammation. Circulating PKM2 levels correlated with average target to background ratios PET scores. CONCLUSION: Elevated plasma PKM2 levels reflect active vessel inflammation in GCA and may assist in disease diagnosis and in disease monitoring.


Assuntos
Proteínas de Transporte , Arterite de Células Gigantes , Proteínas de Membrana , Hormônios Tireóideos , Biomarcadores/sangue , Proteínas de Transporte/sangue , Proteína 1 Semelhante à Quitinase-3 , Fluordesoxiglucose F18 , Arterite de Células Gigantes/diagnóstico por imagem , Arterite de Células Gigantes/patologia , Humanos , Inflamação , Complexo Antígeno L1 Leucocitário , Proteínas de Membrana/sangue , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Piruvato Quinase , Hormônios Tireóideos/sangue , Proteínas de Ligação a Hormônio da Tireoide
3.
J Biol Chem ; 294(15): 6130-6141, 2019 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-30733338

RESUMO

The tetrameric protein transthyretin is a transporter of retinol and thyroxine in blood, cerebrospinal fluid, and the eye, and is secreted by the liver, choroid plexus, and retinal epithelium, respectively. Systemic amyloid deposition of aggregated transthyretin causes hereditary and sporadic amyloidoses. A common treatment of patients with hereditary transthyretin amyloidosis is liver transplantation. However, this procedure, which replaces the patient's variant transthyretin with the WT protein, can fail to stop subsequent cardiac deposition, ultimately requiring heart transplantation. We recently showed that preformed amyloid fibrils present in the heart at the time of surgery can template or seed further amyloid aggregation of native transthyretin. Here we assess possible interventions to halt this seeding, using biochemical and EM assays. We found that chemical or mutational stabilization of the transthyretin tetramer does not hinder amyloid seeding. In contrast, binding of the peptide inhibitor TabFH2 to ex vivo fibrils efficiently inhibits amyloid seeding by impeding self-association of the amyloid-driving strands F and H in a tissue-independent manner. Our findings point to inhibition of amyloid seeding by peptide inhibitors as a potential therapeutic approach.


Assuntos
Neuropatias Amiloides Familiares , Amiloide , Peptídeos/química , Pré-Albumina , Agregados Proteicos , Idoso , Idoso de 80 Anos ou mais , Amiloide/antagonistas & inibidores , Amiloide/química , Amiloide/genética , Amiloide/metabolismo , Neuropatias Amiloides Familiares/genética , Neuropatias Amiloides Familiares/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pré-Albumina/antagonistas & inibidores , Pré-Albumina/química , Pré-Albumina/genética , Pré-Albumina/metabolismo
4.
Rheumatology (Oxford) ; 59(1): 176-184, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31292652

RESUMO

OBJECTIVES: PMR frequently co-occurs with GCA. So far, a simple biomarker for detecting concomitant arterial inflammation in PMR patients is lacking. Furthermore, biomarkers predicting disease course in PMR are awaited. We here investigated the diagnostic and prognostic value of acute-phase markers (ESR, CRP, IL-6, serum amyloid A) and angiogenesis markers (VEGF, soluble Tie2, angiopoietin-1, angiopoietin-2) in isolated PMR and PMR/GCA overlap patients. METHODS: We prospectively included 39 treatment-naïve PMR patients, of whom 10 patients also showed evidence of large vessel GCA by PET-CT. Age-matched healthy controls (n = 32) and infection controls (n = 13) were included for comparison. Serum marker levels were measured by an ELISA or Luminex assay. Receiver operating characteristic and Kaplan-Meier analyses were used to asses diagnostic and prognostic accuracy, respectively. RESULTS: All acute-phase and angiogenesis markers, except angiopoietin-1, were higher in isolated PMR patients than in healthy controls. Angiopoietin-2, ESR and soluble Tie-2 were significantly higher in patients with PMR/GCA overlap than in isolated PMR patients. Angiopoeietin-2, but not soluble Tie2, outperformed ESR and CRP in discriminating patients with and without overlapping GCA (area under the curve: 0.90; sensitivity: 100%; specificity: 76%). Moreover, high angiopoietin-2 levels were associated with long-term glucocorticoid requirement. CONCLUSION: Assessment of angiopoietin-2 at baseline may assist diagnosis of concomitant vasculitis in PMR. Moreover, high levels of angiopoietin-2 were associated with an unfavourable disease course in isolated PMR patients. These findings imply that angiopoietin-2 is an interesting diagnostic and prognostic biomarker in PMR.


Assuntos
Angiopoietina-2/sangue , Arterite de Células Gigantes/etiologia , Polimialgia Reumática/sangue , Prednisolona/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Arterite de Células Gigantes/sangue , Arterite de Células Gigantes/diagnóstico , Glucocorticoides/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Polimialgia Reumática/complicações , Polimialgia Reumática/diagnóstico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prognóstico , Estudos Prospectivos
5.
Artigo em Inglês | MEDLINE | ID: mdl-30805622

RESUMO

OBJECTIVE: GCA, a systemic vasculitis, is characterized by an IL-6-dependent acute-phase response. This response is typically suppressed by treatment rendering CRP/ESR unreliable for monitoring vascular inflammation. Also, there are no accurate biomarkers predicting a non-favourable disease course. Here we investigated macrophage products and markers of angiogenesis as biomarkers for prognosis and monitoring of vascular inflammation. METHODS: Forty-one newly diagnosed, glucocorticoid-naive GCA patients were prospectively followed for relapses and glucocorticoid requirement for a median of 30 months (range 0-71). Serum markers at baseline and during follow-up were compared with 33 age-matched healthy controls and 13 infection controls. Concentrations of IL-6, serum amyloid A, soluble CD163, calprotectin, YKL-40, VEGF, angiopoietin-1 and -2 and sTie2 were determined by ELISA/Luminex assay. RESULTS: Serum concentrations of all markers, but not angiopoietin-1, were elevated in GCA patients at baseline when compared with healthy controls. High VEGF (P = 0.0025) and angiopoietin-1 (P = 0.0174) and low YKL-40 (P = 0.0369) levels at baseline were predictive of a short time to glucocorticoid-free remission. Elevated angiopoietin-2 levels were associated with an imminent relapse during treatment (P < 0.05). IL-6 correlated strongly with acute-phase markers and soluble CD163 but not with markers of angiogenesis, YKL-40 or calprotectin. Glucocorticoid treatment down-modulated all markers except for calprotectin and YKL-40. Tissue expression of markers in temporal arteries was confirmed. CONCLUSION: Markers of angiogenesis at baseline and during treatment predict GCA disease course, suggesting utility in patient stratification for glucocorticoid-sparing therapy. Calprotectin and YKL-40 are candidate markers for monitoring vessel wall inflammation.

6.
Rheumatology (Oxford) ; 57(10): 1812-1821, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29982712

RESUMO

Objectives: Serum immunoglobulin free light chains (FLCs) are frequently elevated in B-cell-mediated autoimmune diseases, including primary SS (pSS). The objective of this study was to assess if serum FLCs can contribute to classification, mucosa-associated lymphoid tissue (MALT) lymphoma detection, monitoring of disease activity and treatment response in pSS. Methods: Serum samples of 100 consecutive patients suspected of pSS were included. Forty-five patients fulfilled ACR-EULAR criteria for pSS. Additionally, samples of 17 pSS patients with MALT lymphoma and longitudinal samples of pSS patients treated with rituximab (n = 20), placebo (n = 10) or abatacept (n = 15) were included. Serum FLCκ/FLCλ was measured by nephelometry or turbidimetry. Results: At diagnosis, FLCκ and FLCλ serum levels were significantly higher in pSS compared with non-SS sicca patients. The FLCκ/FLCλ ratio was abnormal in 11% of pSS patients. In established MALT-pSS patients, without recent rituximab treatment (n = 12), 50% had abnormal FLCκ/FLCλ ratios. FLC measurement had no additional value for pSS classification, compared with IgG and anti-SSA. FLC levels correlated significantly with systemic disease activity, assessed by EULAR SS Disease Activity Index (ESSDAI) and clinical ESSDAI, both cross-sectionally and longitudinally following treatment. Treatment with rituximab or abatacept significantly lowered FLC levels. FLCs show a large sensitivity to change and relative changes induced by treatment were higher compared with IgG. Conclusion: Serum FLCs are elevated in pSS, and abnormal FLCκ/FLCλ ratios may be indicative for the presence of MALT lymhoma. FLC levels can be used as a biomarker for systemic disease activity and monitoring treatment responses. FLCs are sensitive to change and have more favorable kinetics than IgG.


Assuntos
Cadeias Leves de Imunoglobulina/sangue , Fatores Imunológicos/uso terapêutico , Linfoma de Zona Marginal Tipo Células B/sangue , Síndrome de Sjogren/sangue , Abatacepte/uso terapêutico , Adulto , Biomarcadores/sangue , Feminino , Humanos , Estudos Longitudinais , Linfoma de Zona Marginal Tipo Células B/imunologia , Masculino , Pessoa de Meia-Idade , Monitorização Imunológica , Ensaios Clínicos Controlados Aleatórios como Assunto , Rituximab/uso terapêutico , Síndrome de Sjogren/tratamento farmacológico , Síndrome de Sjogren/imunologia , Resultado do Tratamento
7.
Am J Kidney Dis ; 69(4): 546-549, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28024929

RESUMO

A 52-year-old woman with widely disseminated medullary thyroid carcinoma developed nephrotic syndrome and slowly decreasing kidney function. A kidney biopsy was performed to differentiate between malignancy-associated membranous glomerulopathy and tyrosine kinase inhibitor-induced focal segmental glomerulosclerosis. Surprisingly, the biopsy specimen revealed diffuse glomerular deposition of amyloid that was proved to be derived from the calcitonin hormone (Acal), produced by the medullary thyroid carcinoma. This amyloid was also present in an abdominal fat pad biopsy. Although local ACal deposition is a characteristic feature of medullary thyroid carcinoma, the systemic amyloidosis involving the kidney that is presented in this case report has not to our knowledge been described previously and may be the result of long-term high plasma calcitonin levels. Our case illustrates that systemic calcitonin amyloidosis should be considered in the differential diagnosis of proteinuria in patients with medullary thyroid carcinoma.


Assuntos
Amiloidose/patologia , Calcitonina/metabolismo , Carcinoma Medular/patologia , Hormônios Ectópicos/metabolismo , Falência Renal Crônica/patologia , Glomérulos Renais/patologia , Placa Amiloide/patologia , Neoplasias da Glândula Tireoide/patologia , Gordura Abdominal/patologia , Biópsia , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Síndrome Nefrótica/patologia , Proteinúria/patologia
9.
Rheumatology (Oxford) ; 54(8): 1397-402, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25724206

RESUMO

OBJECTIVE: To compare multiple serum markers for their ability to detect active disease in patients with GCA and in those with PMR. METHODS: Twenty-six markers related to immune cells that may be involved in GCA and PMR were determined by ELISA and multiplex assay in the serum of 24 newly diagnosed, untreated GCA/PMR patients, 14 corticosteroid (CS)-treated GCA/PMR patients in remission and 13 healthy controls. Receiver operating characteristic analysis with area under the curve and Spearman's correlation coefficients were performed. RESULTS: Serum B-cell activating factor (BAFF), CXCL9 and IL-6 were increased in newly diagnosed GCA and PMR patients. Serum CCL2, CCL11, IL-10 and sIL-2R were modulated in GCA patients only and CXCL10 in PMR patients only. BAFF, CXCL9 and IL-6 accurately distinguished newly diagnosed GCA and PMR patients from healthy controls, as shown by area under the curve > 0.80. Upon CS-induced remission, serum BAFF and IL-6 decreased significantly in both GCA and PMR patients, whereas CXCL9 remained high. Serum BAFF and IL-6 correlated strongly with ESR and CRP in GCA and PMR patients. CONCLUSION: Among the serum markers tested, BAFF and IL-6 showed the strongest association with disease activity in both GCA and PMR patients. The diagnostic value of these markers should be evaluated in larger, longitudinal studies with GCA and PMR patients, and in patients with infections or other inflammatory conditions.


Assuntos
Fator Ativador de Células B/sangue , Arterite de Células Gigantes/diagnóstico , Interleucina-6/sangue , Polimialgia Reumática/diagnóstico , Índice de Gravidade de Doença , Idoso , Biomarcadores/sangue , Sedimentação Sanguínea , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Quimiocina CXCL9/sangue , Feminino , Arterite de Células Gigantes/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Polimialgia Reumática/sangue , Valor Preditivo dos Testes
11.
Nutrients ; 16(5)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38474754

RESUMO

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a growing healthcare problem with limited therapeutic options. Progress in this field depends on the availability of reliable preclinical models. Human precision-cut liver slices (PCLSs) have been employed to replicate the initiation of MASLD, but a comprehensive investigation into MASLD progression is still missing. This study aimed to extend the current incubation time of human PCLSs to examine different stages in MASLD. Healthy human PCLSs were cultured for up to 96 h in a medium enriched with high sugar, high insulin, and high fatty acids to induce MASLD. PCLSs displayed hepatic steatosis, characterized by accumulated intracellular fat. The development of hepatic steatosis appeared to involve a time-dependent impact on lipid metabolism, with an initial increase in fatty acid uptake and storage, and a subsequent down-regulation of lipid oxidation and secretion. PCLSs also demonstrated liver inflammation, including increased pro-inflammatory gene expression and cytokine production. Additionally, liver fibrosis was also observed through the elevated production of pro-collagen 1a1 and tissue inhibitor of metalloproteinase-1 (TIMP1). RNA sequencing showed that the tumor necrosis factor alpha (TNFα) signaling pathway and transforming growth factor beta (TGFß) signaling pathway were consistently activated, potentially contributing to the development of inflammation and fibrosis. In conclusion, the prolonged incubation of human PCLSs can establish a robust ex vivo model for MASLD, facilitating the identification and evaluation of potential therapeutic interventions.


Assuntos
Fígado Gorduroso , Doenças Metabólicas , Humanos , Avaliação Pré-Clínica de Medicamentos , Inibidor Tecidual de Metaloproteinase-1 , Inflamação
12.
Amyloid ; 31(2): 132-141, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38477065

RESUMO

OBJECTIVE: To evaluate serum neurofilament light chain (sNfL) as biomarker of disease onset, progression and treatment effect in hereditary transthyretin (ATTRv) amyloidosis patients and TTR variant (TTRv) carriers. METHODS: sNfL levels were assessed longitudinally in persistently asymptomatic TTRv carriers (N = 12), persistently asymptomatic ATTRv amyloidosis patients (defined as asymptomatic patients but with amyloid detectable in subcutaneous abdominal fat tissue) (N = 8), in TTRv carriers who developed polyneuropathy (N = 7) and in ATTRv amyloidosis patients with polyneuropathy on treatment (TTR-stabiliser (N = 20) or TTR-silencer (N = 18)). Polyneuropathy was confirmed by nerve conduction studies or quantitative sensory testing. sNfL was analysed using a single-molecule array assay. RESULTS: sNfL increased over 2 years in persistently asymptomatic ATTRv amyloidosis patients, but did not change in persistently asymptomatic TTRv carriers. In all TTRv carriers who developed polyneuropathy, sNfL increased from 8.4 to 49.8 pg/mL before the onset of symptoms and before polyneuropathy could be confirmed neurophysiologically. In symptomatic ATTRv amyloidosis patients on a TTR-stabiliser, sNfL remained stable over 2 years. In patients on a TTR-silencer, sNfL decreased after 1 year of treatment. CONCLUSION: sNfL is a biomarker of early neuronal damage in ATTRv amyloidosis already before the onset of polyneuropathy. Current data support the use of sNfL in screening asymptomatic TTRv carriers and in monitoring of disease progression and treatment effect.


Assuntos
Neuropatias Amiloides Familiares , Biomarcadores , Proteínas de Neurofilamentos , Pré-Albumina , Humanos , Neuropatias Amiloides Familiares/sangue , Neuropatias Amiloides Familiares/genética , Neuropatias Amiloides Familiares/patologia , Proteínas de Neurofilamentos/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Biomarcadores/sangue , Idoso , Pré-Albumina/genética , Pré-Albumina/metabolismo , Estudos Longitudinais , Adulto , Polineuropatias/sangue , Polineuropatias/genética , Polineuropatias/patologia , Polineuropatias/diagnóstico , Neurônios/metabolismo , Neurônios/patologia
13.
J Clin Med ; 13(3)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38337504

RESUMO

(1) Background: Individuals carrying a pathogenic transthyretin gene variant (TTRv) are at high risk for developing hereditary transthyretin (ATTRv) amyloidosis and are routinely screened for the development of cardiomyopathy (ATTRv-CM). This study aims to evaluate whether the cardiac biomarkers N-terminal pro B-type natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin T (hs-cTnT) can be used to rule out ATTRv-CM. (2) Methods: In this retrospective case-control study, data from 46 ATTRv-CM patients and 101 TTRv carriers and ATTRv amyloidosis patients without cardiomyopathy were included. Binary logistic regression models were used to assess the ability of NT-proBNP and hs-cTnT to predict the diagnosis of ATTRv-CM. An optimal cutoff for the relevant biomarker(s) was determined based on a sensitivity of ≥99% and the highest possible percentage of additional tests avoided (%ATA) in the index dataset. (3) Results: Hs-cTnT demonstrated the highest predictive capabilities for ATTRv-CM. The addition of NT-proBNP did not improve the predictive model. A hs-cTnT cutoff of <6 ng/L resulted in a 97% sensitivity and a negative predictive value of 95% with a %ATA of 30% in the validation dataset. (4) Conclusion: In conclusion, hs-cTnT is a useful biomarker for excluding cardiac involvement in TTRv carriers and ATTRv amyloidosis patients and it has the potential to prevent unnecessary diagnostic procedures.

14.
Cells ; 12(5)2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36899835

RESUMO

AL amyloidosis is caused by the misfolding of immunoglobulin light chains leading to an impaired function of tissues and organs in which they accumulate. Due to the paucity of -omics profiles from undissected samples, few studies have addressed amyloid-related damage system wide. To fill this gap, we evaluated proteome changes in the abdominal subcutaneous adipose tissue of patients affected by the AL isotypes κ and λ. Through our retrospective analysis based on graph theory, we have herein deduced new insights representing a step forward from the pioneering proteomic investigations previously published by our group. ECM/cytoskeleton, oxidative stress and proteostasis were confirmed as leading processes. In this scenario, some proteins, including glutathione peroxidase 1 (GPX1), tubulins and the TRiC complex, were classified as biologically and topologically relevant. These and other results overlap with those already reported for other amyloidoses, supporting the hypothesis that amyloidogenic proteins could induce similar mechanisms independently of the main fibril precursor and of the target tissues/organs. Of course, further studies based on larger patient cohorts and different tissues/organs will be essential, which would be a key point that would allow for a more robust selection of the main molecular players and a more accurate correlation with clinical aspects.


Assuntos
Amiloidose de Cadeia Leve de Imunoglobulina , Humanos , Proteômica/métodos , Estudos Retrospectivos , Biópsia , Gordura Subcutânea/metabolismo
15.
J Neuroinflammation ; 9: 198, 2012 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-22894638

RESUMO

BACKGROUND: Neuroprotective and neurotrophic properties of leukemia inhibitory factor (LIF) have been widely reported. In the central nervous system (CNS), astrocytes are the major source for LIF, expression of which is enhanced following disturbances leading to neuronal damage. How astrocytic LIF expression is regulated, however, has remained an unanswered question. Since neuronal stress is associated with production of extracellular adenosine, we investigated whether LIF expression in astrocytes was mediated through adenosine receptor signaling. METHODS: Mouse cortical neuronal and astrocyte cultures from wild-type and adenosine A(2B) receptor knock-out animals, as well as adenosine receptor agonists/antagonists and various enzymatic inhibitors, were used to study LIF expression and release in astrocytes. When needed, a one-way analysis of variance (ANOVA) followed by Bonferroni post-hoc test was used for statistical analysis. RESULTS: We show here that glutamate-stressed cortical neurons induce LIF expression through activation of adenosine A(2B) receptor subtype in cultured astrocytes and require signaling of protein kinase C (PKC), mitogen-activated protein kinases (MAPKs: p38 and ERK1/2), and the nuclear transcription factor (NF)-κB. Moreover, LIF concentration in the supernatant in response to 5'-N-ethylcarboxamide (NECA) stimulation was directly correlated to de novo protein synthesis, suggesting that LIF release did not occur through a regulated release pathway. Immunocytochemistry experiments show that LIF-containing vesicles co-localize with clathrin and Rab11, but not with pHogrin, Chromogranin (Cg)A and CgB, suggesting that LIF might be secreted through recycling endosomes. We further show that pre-treatment with supernatants from NECA-treated astrocytes increased survival of cultured cortical neurons against glutamate, which was absent when the supernatants were pre-treated with an anti-LIF neutralizing antibody. CONCLUSIONS: Adenosine from glutamate-stressed neurons induces rapid LIF release in astrocytes. This rapid release of LIF promotes the survival of cortical neurons against excitotoxicity.


Assuntos
Astrócitos/metabolismo , Córtex Cerebral/metabolismo , Fármacos Atuantes sobre Aminoácidos Excitatórios/toxicidade , Fator Inibidor de Leucemia/metabolismo , Neurônios/metabolismo , Receptor A2B de Adenosina/fisiologia , Animais , Células Cultivadas , Ácido Glutâmico/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fármacos Neuroprotetores/metabolismo , Receptor A2B de Adenosina/uso terapêutico
16.
Front Neurol ; 13: 877050, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35665051

RESUMO

Few studies on traumatic brain injury (TBI) have investigated the stability of blood serum biomarkers after long-term storage at low temperatures. In the current feasibility study we analyzed acute phase serum samples from patients with mild TBI as well as patients with moderate and severe TBI that were collected more than 10 years ago (old samples). We were particularly interested in mild TBI, because injury effects are more subtle in this category as compared to moderate-severe TBI. Therefore, the primary objective was to find out whether several biomarkers were still detectable for these patients. Additionally, we examined whether biomarker levels varied as a function of injury severity. For comparison, we also analyzed samples from an ongoing mTBI cohort (new samples) and healthy controls. Samples were treated with care and were not being subjected to freeze-thaw cycles. We measured concentrations of interleukins (IL6 and 10) and brain specific markers (total tau, UCH-L1, GFAP, and NF-L). No significant differences in biomarker concentrations were found between old and new mild TBI samples. For IL6, IL10, and UCH-L1 higher concentrations were found in moderate and severe TBI as compared to mild TBI. In conclusion, our study shows that long-term storage does not rule out the detection of meaningful biomarker concentrations in patients with TBI, although further research by other laboratories is warranted.

17.
Nat Commun ; 13(1): 7261, 2022 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-36433936

RESUMO

Systemic AA amyloidosis is a debilitating protein misfolding disease in humans and animals. In humans, it occurs in two variants that are called 'vascular' and 'glomerular', depending on the main amyloid deposition site in the kidneys. Using cryo electron microscopy, we here show the amyloid fibril structure underlying the vascular disease variant. Fibrils purified from the tissue of such patients are mainly left-hand twisted and contain two non-equal stacks of fibril proteins. They contrast in these properties to the fibrils from the glomerular disease variant which are right-hand twisted and consist of two structurally equal stacks of fibril proteins. Our data demonstrate that the different disease variants in systemic AA amyloidosis are associated with different fibril morphologies.


Assuntos
Amiloidose , Amiloidose de Cadeia Leve de Imunoglobulina , Nefropatias , Animais , Humanos , Amiloide/metabolismo , Amiloidose/metabolismo , Amiloidose de Cadeia Leve de Imunoglobulina/metabolismo , Microscopia Crioeletrônica
18.
Amyloid ; 28(4): 243-251, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34338090

RESUMO

Several studies recently showed that ex vivo fibrils from patient or animal tissue were structurally different from in vitro formed fibrils from the same polypeptide chain. Analysis of serum amyloid A (SAA) and Aß-derived amyloid fibrils additionally revealed that ex vivo fibrils were more protease stable than in vitro fibrils. These observations gave rise to the proteolytic selection hypothesis that suggested that disease-associated amyloid fibrils were selected inside the body by their ability to resist endogenous clearance mechanisms. We here show, for more than twenty different fibril samples, that ex vivo fibrils are more protease stable than in vitro fibrils. These data support the idea of a proteolytic selection of pathogenic amyloid fibril morphologies and help to explain why only few amino acid sequences lead to amyloid diseases, although many, if not all, polypeptide chains can form amyloid fibrils in vitro.


Assuntos
Amiloide , Amiloidose , Sequência de Aminoácidos , Animais , Humanos , Peptídeo Hidrolases , Proteína Amiloide A Sérica
19.
Amyloid ; 28(1): 50-55, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32883119

RESUMO

OBJECTIVE: To study serum neurofilament light chain (sNfL) in amyloid light chain (AL) amyloidosis patients with and without polyneuropathy (PNP) and to corroborate previous observations that sNfL is increased in hereditary transthyretin-related (ATTRv) amyloidosis patients with PNP. METHODS: sNfL levels were assessed retrospectively in patients with AL amyloidosis with and without PNP (AL/PNP+ and AL/PNP-, respectively), patients with ATTRv amyloidosis and PNP (ATTRv/PNP+), asymptomatic transthyretin (TTR) gene mutation carriers (TTRv carriers) and healthy controls. Healthy controls (HC) were age- and sex-matched to both AL/PNP- (HC/AL) and TTRv carriers (HC/TTRv). The single-molecule array (Simoa) assay was used to assess sNfL levels. RESULTS: sNfL levels were increased both in 10 AL/PNP+ patients (p < .001) and in 10 AL/PNP- patients (p < .005) compared to 10 HC/AL individuals. sNfL levels were higher in AL/PNP+ patients than in AL/PNP- patients (p < .005). sNfL levels were also increased in 15 ATTRv/PNP+ patients, compared to both 15 HC/TTRv (p < .0001) and 15 TTRv carriers (p < .0001). ATTRv/PNP+ patients with progressive PNP (PND-score > I) had the highest sNfL levels compared to patients with early PNP (PND-score I) (p = .05). sNfL levels did not differ between TTRv carriers and HC/TTRv individuals. In the group comprising all healthy controls and in the group of TTRv carriers, sNfL levels correlated with age. CONCLUSION: sNfL levels are increased in patients with PNP in both AL and ATTRv amyloidosis and are related to severity of PNP in ATTRv amyloidosis. sNfL is a promising biomarker to detect PNP, not only in ATTRv but also in AL amyloidosis.


Assuntos
Neuropatias Amiloides Familiares/genética , Amiloidose de Cadeia Leve de Imunoglobulina/genética , Proteínas de Neurofilamentos/sangue , Polineuropatias/genética , Pré-Albumina/genética , Idoso , Amiloide/sangue , Amiloide/genética , Neuropatias Amiloides Familiares/complicações , Neuropatias Amiloides Familiares/patologia , Biomarcadores/sangue , Encéfalo/metabolismo , Encéfalo/patologia , Feminino , Heterozigoto , Humanos , Amiloidose de Cadeia Leve de Imunoglobulina/complicações , Amiloidose de Cadeia Leve de Imunoglobulina/patologia , Masculino , Pessoa de Meia-Idade , Proteínas de Neurofilamentos/genética , Polineuropatias/etiologia , Polineuropatias/patologia
20.
Clin Exp Rheumatol ; 28(1 Suppl 57): 18-23, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20412697

RESUMO

INTRODUCTION: Atherosclerosis is accelerated in Wegener's granulomatosis (WG) patients. This study was aimed to assess which factors can predict progression of atherosclerosis in WG. METHODS: 23 WG patients (14 men; age 47+/-9 years, mean+/-SD) and 21 controls (12 men; age 47+/-10 years) were included. Intima-media thickness (IMT) was determined by ultrasound, as measure for atherosclerosis. After median follow-up of 72 months (interquartile range: 66-76), IMT was repeated. Traditional risk factors for cardiovascular disease were determined, as well as levels of C-reactive protein (CRP) and endothelial activation markers, including thrombomodulin, vascular cell adhesion molecule-1 (VCAM-1) and von Willebrand factor (vWf). Disease-related factors were recorded from time of diagnosis until end of follow-up. RESULTS: Maximum IMT at both evaluations was increased in patients. Patients had an increased prevalence of hypertension and increased levels of vWf and CRP. IMT progression was not different. IMT at follow-up was positively associated with age, blood pressure, CRP and VCAM-1, and negatively with HDL. During follow-up, disease activity was lower compared to the period from diagnosis until the first evaluation, and blood pressure and prevalence of dyslipidemia decreased in WG patients. Change in IMT was not correlated to any risk factor measured. CONCLUSIONS: Maximum IMT was increased in WG patients. Progression of IMT was not different between patients and controls, probably because disease activity was low and reduction of traditional risk factors was achieved during follow-up. We suggest that control of disease activity and treatment of traditional risk factors are important to prevent cardiovascular disease in WG.


Assuntos
Aterosclerose , Biomarcadores/sangue , Granulomatose com Poliangiite , Adulto , Aterosclerose/diagnóstico por imagem , Aterosclerose/epidemiologia , Aterosclerose/metabolismo , Proteína C-Reativa/metabolismo , Progressão da Doença , Endotélio Vascular/metabolismo , Feminino , Seguimentos , Granulomatose com Poliangiite/diagnóstico por imagem , Granulomatose com Poliangiite/epidemiologia , Granulomatose com Poliangiite/metabolismo , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Túnica Íntima/diagnóstico por imagem , Túnica Média/diagnóstico por imagem , Ultrassonografia , Molécula 1 de Adesão de Célula Vascular/sangue , Fator de von Willebrand/metabolismo
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