Oxidative stress and skeletal muscle dysfunction are present in healthy smokers

Chronic exposure to cigarette smoke seems to be related to an increase of pro-inflammatory cytokines, oxidative stress and changes in muscular and physical performances of healthy smokers. However, these parameters have not yet been evaluated simultaneously in previous studies. The participants of this study were healthy males divided into two groups: smokers (n=20) and non-smokers (n=20). Inflammation was evaluated by measuring plasma levels of the cytokines IL-10, IL-6 e TNF-α, and of the soluble receptors sTNFR1 and sTNFR2. Oxidative stress was evaluated by determination of thiobarbituric acid reactive substances (TBARS) plasma levels, total antioxidant capacity of plasma and erythrocytes activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase. Muscular performance was evaluated by measuring the peak torque of knee flexors and extensors, and by determining the total work of the knee extensors. Physical performance was assessed by measuring the peak oxygen uptake (VO2 peak), the maximum heart rate (HRmax) and the walking distance in the shuttle walking test. Smokers showed an increase in the levels of the sTNFR1 and TBARS and a decrease in the total antioxidant capacity of plasma, in the catalase activity and in the total work (P<0.05). IL-6, IL-10, sTNFR2, SOD, peak torque, VO2 peak, HRmax and walking distance were similar between groups. Smokers presented increased oxidative stress and skeletal muscle dysfunction, demonstrating that the changes in molecular and muscular parameters occur simultaneously in healthy smokers.

Serial measurement of the circulating levels of tumour necrosis factor and its soluble receptors 1 and 2 for monitoring leprosy patients during multidrug treatment

Leprosy is an infectious and contagious spectral disease accompanied by a series of immunological events triggered by the host response to the aetiologic agent, Mycobacterium leprae . The induction and maintenance of the immune/inflammatory response in leprosy are linked to multiple cell interactions and soluble factors, primarily through the action of cytokines. The purpose of the present study was to evaluate the serum levels of tumour necrosis factor (TNF)-α and its soluble receptors (sTNF-R1 and sTNF-R2) in leprosy patients at different stages of multidrug treatment (MDT) in comparison with non-infected individuals and to determine their role as putative biomarkers of the severity of leprosy or the treatment response. ELISA was used to measure the levels of these molecules in 30 healthy controls and 37 leprosy patients at the time of diagnosis and during and after MDT. Our results showed increases in the serum levels of TNF-α and sTNF-R2 in infected individuals in comparison with controls. The levels of TNF-α, but not sTNF-R2, decreased with treatment. The current results corroborate previous reports of elevated serum levels of TNF-α in leprosy and suggest a role for sTNF-R2 in the control of this cytokine during MDT.

Avaliacao comparativa entre os metodos objetivo e subjetivo em laminas coradas pela imuno-histoquimica / Comparative assessment between objective and subjective methods in slides stained by immunohistochemistry

Métodos objetivos de avaliação são frequentemente cobrados em estudos científicos. Exames histológicos com coloração imuno-histoquímica podem ser avaliados por meio de fotometria. OBJETIVO: Comparar este método objetivo com a avaliação subjetiva realizada por três observadores independentes, utilizando lâminas de colesteatoma adquirido da orelha média. MÉTODO: Foram selecionadas um total de 54 imagens de colesteatomas imuno-histoquimicamente coradas pelos anticorpos anti-TNF-R2 (32 lâminas) e anti-TGF-α; (22 lâminas). O anticorpo secundário utilizado nos dois grupos foi o Max Polimer Detection System (Kit Novo Link, Novocastra®, UK). As amostras foram processadas por um scanner digital de lâminas (modelo ScanScope - Aperio). As áreas selecionadas foram submetidas à análise por fotometria. RESULTADOS: A avaliação objetiva por fotometria foi comparada com a avaliação subjetiva por três observadores e submetidas à análise estatística. A análise estatística revelou reprodutibilidade moderada (K valores entre 0,41 e 0,60) para os dois grupos. CONCLUSÃO: O presente estudo demonstrou que as características irregulares das lâminas de colesteatoma da orelha média coradas pela imuno-histoquímica impossibilita a sua adequada avaliação objetiva, enquanto a avaliação subjetiva por observadores experientes se mostrou mais confiável. .

Objective methods of assessment are often required in scientific studies. Histological tests with immunohistochemical staining can be assessed by photometry. OBJECTIVE: To compare this objective method with the subjective evaluation performed by three independent examiners, using slides of acquired middle ear cholesteatomas. METHOD: We selected a total of 54 cholesteatoma images, immunohistochemically stained by anti-TNF-R2 (32 slides) and anti-TGF-α, (22 slides). The secondary antibody used in the two groups was the Max Polymer Detection System (Novo Link Kit, Novocastra®, UK). The samples were processed by a digital slide scanner (ScanScope - Aperio). The selected sites were analyzed by photometry. RESULTS: The objective assessment by photometry was compared with the subjective evaluation by three examiners and subjected to statistical analysis. The Statistical analysis revealed moderate reproducibility (K values between 0.41 and 0.60) for both groups. CONCLUSION: Our study showed that the irregular characteristics of middle ear cholesteatoma slides stained by immunohistochemistry prevents its proper objective evaluation, while the subjective assessment by experienced examiners was more reliable. .

Serum levels of soluble TNF-a receptors but not BDNF are associated with apathy symptoms in mild Alzheimer's disease and amnestic mild cognitive impairment / Níveis Séricos de receptores Solúveis Do TNF-a mas não de BDNF estão associados a sintomas de apatia na doença de Alzheimer leve e no comprometimento cognitivo leve amnéstico

Apathy is intimately associated with dementia. Unfortunately, its pathophysiology remains poorly understood. The motivational impairment that characterizes this disorder might share the same inflammatory mechanisms, as suggested by the sickness behavior theory. OBJECTIVE: The primary aim of this study was to investigate the association between apathy symptoms and serum levels of tumor necrosis factor alpha (TNF-a) and its soluble receptors. Brain-derived neurotrophic factor (BDNF) levels were also analyzed since these have been associated with depression, a condition which shares abulic features with apathy. METHODS: The sample consisted of 27 subjects with mild Alzheimer's disease or amnestic mild cognitive impairment, who were submitted to specific apathy evaluation using the Apathy Scale (AS) and provided blood samples for biomarker analysis. Participants were categorized into two groups according to median AS scores (17 points). RESULTS: Subjects with higher apathy symptoms (n=13) displayed higher levels of TNF-a soluble receptors (type 1: p=0.03; type 2: p=0.04). No other difference was found between groups. CONCLUSION: These findings point to the involvement of inflammatory mediators in the genesis of apathy symptoms, as suggested by the sickness behavior theory.

Apatia está intimamente associada à demência. Lamentavelmente, sua fisiopatologia ainda é pouco compreendida. O comprometimento motivacional que caracteriza este transtorno poderia compartilhar mecanismos inflamatórios como sugere a teoria do comportamento associado à doença. OBJETIVO: O principal objetivo deste estudo foi investigar a associação entre apatia e os níveis séricos do fator de necrose tumoral alfa (TNF-a) e de seus receptores solúveis. Os níveis de fator neurotrófico derivado do cérebro também foram analisados já que estes foram associados à depressão, que compartilha aspectos abúlicos com a apatia. MÉTODOS: A amostra consistiu de 27 indivíduos com doença de Alzheimer leve ou com comprometimento cognitivo leve amnéstico, que foram submetidos à avaliação de apatia pela Escala de Apatia (EA), e proveram amostra de sangue para análise de biomarcadores. De acordo com a mediana de escores na EA (17 pontos), a amostra foi divida em dois grupos. RESULTADOS: O grupo com mais sintomas de apatia apresentou maiores níveis séricos de receptores solúveis de TNF-a (tipo 1: p=0,03 ; tipo 2: p=0,04). Nenhuma outra diferença foi encontrada entre os grupos.CONCLUSÃO: Estes achados sugerem o envolvimento de mediadores inflamatórios na gênese de sintomas de apatia, assim como sugere a teoria do comportamento associado à doença.

Increased serum levels of soluble tumor necrosis factor receptor-2 (sTNFR2) in patients with active toxoplasmic retinochoroiditis

This study aimed to investigate the serum levels of the cytokine TNF-α and its soluble receptors (sTNFR1 and sTNFR2) in patients with toxoplasmosis retinochoroidits (TR) and controls. 37 patients with TR and 30 subjects with positive serology for toxoplasmosis but without history and signs of uveitis were included in this study. Serum concentrations of TNF-α, sTNFR1, and sTNFR2 were determined by ELISA. Serum concentrations of TNF-α and sTNFR1 were similar in controls (mean ± SD median values; 56.57 ± 141.96 and 504.37 ± 163.87, respectively) and TR patients (mean ± SD values, 121.62 ± 217.56 and 511.15 ± 189.30, respectively). Serum concentrations of sTNFR2 were higher in the uveitis group when compared to the control group (respectively, mean ± SD values, 1734.84 ± 379.32 and 1442.75 ± 309.47; p=0.002). There was no association between the serum levels of the molecules and the time of first symptoms, severity of vitreous haze, size or localization of active lesions, levels of visual acuity, and presence of vasculitis. These results suggest that TR is associated with changes in the circulating levels of inflammatory biomarkers, but they are not correlated with local/ocular signs.

TNF-R2 expression in acquired middle ear cholesteatoma / Expressão do TNF-R2 no colesteatoma adquirido da orelha média

Acquired middle ear cholesteatoma is a disease which promotes bone erosion resulting in potentially serious complications. The tumor necrosis factor alpha (TNF-α) is present in cholesteatoma and it is related to bone erosion, as shown by different authors. To understand the aggressiveness characteristics of cholesteatoma is necessary, however, to better address the presence and distribution of their receptors. OBJECTIVE: To evaluate the expression of type 2 TNF-α receptor (TNF-R2) in fragments of cholesteatoma and correlate it to the degree of inflammation present. MATERIAL AND METHODS: observational cross-sectional study, which analyzed 33 fragments of cholesteatomas through histological analysis and immunohistochemistry (using as primary antibody to TNF-R2 LabVision® brand). The evaluation was performed by means of a qualitative and semi-quantitative agreement with the observed intensity. For statistical analysis we used the Fisher exact test and Spearman´s correlation coefficient (considered statistically significant when p < 0. 05). RESULTS: The expression of TNF-R2 was present in all fragments, however a statistical analysis showed no correlation or association between inflammation and the expression of TNF-R2. CONCLUSIONS: TNF-R2 is present in cholesteatoma of the middle ear, however, its expression is not directly related to the degree of inflammation observed in patients with this disease.

O colesteatoma adquirido da orelha média promove erosão óssea, ocasionando complicações potencialmente graves. O fator de necrose tumoral alfa (TNF-α) está presente no colesteatoma adquirido da orelha média e relaciona-se com a erosão óssea, como demonstraram diferentes autores. Para que se compreenda as características de agressividade do colesteatoma, é necessário que se estude a presença e a distribuição seus receptores. OBJETIVO: Avaliar a expressão do receptor tipo dois do TNF-α (TNF-R2) em fragmentos de colesteatoma e relacioná-lo com o grau de inflamação. MATERIAL E MÉTODOS: Estudo observacional do tipo transversal. Foram analisados 33 fragmentos de colesteatomas, submetidos à análise histológica e imunoistoquímica (utilizando o TNF-R2 da marca Labvision®). A avaliação foi realizada de forma qualitativa e semiquantitativa, de acordo com a intensidade observada. Para a análise estatística, foram utilizados o teste exato de Fischer e o coeficiente de correlação de Spearman (estatisticamente significativo quando p < 0,05). RESULTADOS: A expressão do TNF-R2 estava presente em todos os fragmentos, entretanto a estatística não evidenciou correlação, nem associação entre o processo inflamatório e a expressão do TNF-R2. CONCLUSÕES: O TNF-R2 está presente no colesteatoma adquirido da orelha média. Entretanto, a sua expressão não está relacionada ao grau de inflamação.

Soluble inflammatory markers as predictors of hepatocellular damage and therapeutic response in chronic hepatitis C

Hepatitis C is an important burden worldwide being an important cause of cirrhosis and liver cancer in different parts of the world. Host immune response, especially T helper type 1 (Th1) cell-mediated, seems to play an important role in disease progression but is also crucial for viral elimination following specific therapy. Immune activation can be evaluated using peripheral levels of different cytokines, such as different chemokines (e.g. CCL5, CXCL10) and tumor necrosis factor alpha (TNF-á), and their soluble receptors (e.g. soluble TNF-á receptors 1 (sTNF-R1) and 2 (sTNF-R2). This review article focuses on the potential use of peripheral inflammatory markers as predictors of liver histological changes and therapeutic response among patients with chronic hepatitis C.