Serum levels of melatonin may contribute to the pathogenesis of heart failure in children with median age of 1 year / Níveis séricos da melatonina podem contribuir para a patogênese de insuficiênciacardíaca em crianças com idade média de 1 ano

Abstract Objective: Melatonin has a protective role in adults with cardiovascular disease, but the effects of melatonin in children with cardiac dysfunction are not well understood. This study was designed to explore the variations in melatonin, myeloperoxidase, and caspase-3 levels in children suffering from heart failure. Methods: Seventy-two pediatric patients with heart failure and twelve healthy children were enrolled in this study. A modified Ross scoring system was used to evaluate clinical cardiac function. Patients with a score of >2 points were included in the study and were divided into three groups according to severity of heart failure: mild (score: 3-6), moderate (score: 7-9), and severe (score: 10-12). Echocardiographic parameters, laboratory data, and serum levels of melatonin, myeloperoxidase, and caspase-3 were measured and analyzed in all patients. Results: Compared with patients with mild and moderate heart failure, patients in the severe heart failure group had significantly decreased left ventricular ejection fraction (p < 0.001), and significantly increased serum melatonin levels (p = 0.013) and myeloperoxidase levels (p < 0.001). Serum melatonin levels were positively correlated with serum caspase-3 levels (p < 0.001). The optimal cutoff values of serum melatonin levels for the diagnosis of severe heart failure and primary cardiomyopathy in pediatric patients with heart failure were 54.14 pg/mL and 32.88 pg/mL, respectively. Conclusions: Serum melatonin and myeloperoxidase levels were increased in children with severe heart failure. It is likely that increasing melatonin levels may act as a compensatory mechanism in pediatric children with heart failure.

Resumo Objetivo: A melatonina possui um papel protetor em adultos com doença cardiovascular, porém os efeitos da melatonina em crianças com disfunção cardíaca não são bem entendidos. O estudo foi projetado para explorar a variação nos níveis de melatonina, mieloperoxidase e caspase 3 em crianças que sofrem de insuficiência cardíaca. Métodos: 72 pacientes pediátricos com insuficiência cardíaca e 12 crianças saudáveis foram inscritos no estudo. Um sistema de classificação de Ross modificada foi utilizado para avaliar a função cardíaca clínica. Os pacientes com escore de > 2 pontos foram incluídas no estudo e foram divididos em três grupos de acordo com a gravidade da insuficiência cardíaca: leve (escore: 3-6), moderada (escore: 7-9) e grave (escore: 10-12). Os parâmetros ecocardiográficos, dados laboratoriais e níveis séricos de melatonina, mieloperoxidase e caspase 3 foram medidos e analisados em todos os pacientes. Resultados: Em comparação com os pacientes com insuficiência cardíaca de gravidade leve e moderada, os pacientes no grupo de insuficiência cardíaca grave apresentaram redução significativa da fração de ejeção do ventrículo esquerdo (p < 0,001) e aumento significativo nos níveis séricos de melatonina (p = 0,013) e níveis de mieloperoxidase (p < 0,001). Os níveis séricos de melatonina foram positivamente correlacionados com os níveis séricos de caspase 3 (p < 0,001). Os valores de corte ideais dos níveis séricos de melatonina para diagnóstico de IC e cardiomiopatia primária em pacientes pediátricos com insuficiência cardíaca foram 54,14 pg/mL e 32,88 pg/mL, respectivamente. Conclusões: Os níveis séricos de melatonina e mieloperoxidase mostraram aumento em crianças com insuficiência cardíaca grave. Especulamos se o aumento nos níveis de melatonina pode agir como um mecanismo compensatório em crianças pediátricas com insuficiência cardíaca.

C-reactive protein/albumin ratio is associated with lung function among children/adolescents with cystic fibrosis: a three-year longitudinal study

ABSTRACT BACKGROUND: Chronic lung infections, inflammation and depletion of nutritional status are considered to be prognostic indicators of morbidity in patients with cystic fibrosis. The aim of this study was to investigate the association between inflammatory markers and lung function, nutritional status and morbidity among children/adolescents with cystic fibrosis. DESIGN AND SETTINGS: Prospective three-year longitudinal study conducted in an outpatient clinic in southern Brazil. METHODS: Children/adolescents aged 1-15 years with cystic fibrosis were enrolled. Nutritional status was determined from weight-to-length and body mass index-to-age z-scores and was classified as acceptable, at risk or nutritional failure. Tumor necrosis factor-α, interleukin-1β, myeloperoxidase, C-reactive protein and C-reactive protein/albumin ratio were analyzed. Lung function was evaluated based on the forced expiratory volume in the first second and morbidity according to the number of hospitalizations for pulmonary exacerbation and infections by Pseudomonas aeruginosa. Lung function, nutritional status and morbidity were the outcomes. Odds ratios and 95% confidence intervals were to evaluate the effect of baseline inflammatory markers on the clinical outcomes after three years of follow-up and p-values < 0.05 were considered significant. RESULTS: We evaluated 38 children/adolescents with cystic fibrosis: 55% female; median age (with interquartile range), 3.75 years (2.71-7.00). Children/adolescents with high C-reactive protein/albumin ratio at baseline had odds of 18 (P = 0.018) of presenting forced expiratory volume in the first second ≤ 70% after three years. The other inflammatory markers were not associated with the outcomes. CONCLUSION: C-reactive protein/albumin ratio was associated with forced expiratory volume in the first second ≤ 70% after three years.

Oxidative stress in sepsis. Possible production of free radicals through an erythrocyte-mediated positive feedback mechanism

Abstract Background: Sepsis is an illness with a high morbidity for which no effective treatment exists. Its treatment has a high cost because it usually requires an intensive care unit and expensive antibiotics. The present study focus in the production of reactive oxygen species in the early stages of sepsis. This study aimed at investigating the production of reactive oxygen specie during the inflammatory response in patients with sepsis. Methods: Reactive oxygen specie production and insoluble myeloperoxidase obtained from fresh whole blood were measured by photon counting chemiluminescence in the blood of 18 septic patients and 12 healthy individuals. Modified red blood cells were evaluated by staining of blood smears. The production of reactive oxygen species by macrophages and polymorphonuclear leukocytes put into contact with modified red blood cells were also assessed by photon counting chemiluminescence. Results: The appearance of oxidatively modified erythrocytes, which is an evidence of oxidative stress, was supported by the detection of reactive oxygen species and insoluble myeloperoxidase in the whole blood of all septic patients. Peroxynitrite was the main reactive oxygen species found in the whole blood. Oxidatively modified erythrocytes activated phagocytic cells in vitro, leading to the considerable production of free radicals. Conclusion: It was found that sepsis led to a high oxidative stress and to extensive modification of erythrocytes. It is proposed that a positive feedback mechanism, involving the activation of circulating leukocytes by these modified erythrocytes would maintain the pro-oxidative state even after the disappearance of bacteria.

ANCA-positive vasculitis: Clinical implications of ANCA types and titers / Vasculite ANCA positiva: implicações clínicas dos tipos e dos títulos de ANCA

SUMMARY Introduction: Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is an autoimmune disease that can affect multiple organs, the kidney being one of the most affected. Apart from the diagnostics value of ANCA, they have also been advocated as biomarkers of the disease activity. Recently, the genetic changes found in polyangiitis associated with serine-protease proteinase 3 (PR3)-ANCA or myeloperoxidase (MPO)-ANCA raised the possibility of immune-pathogenic and therapeutic differences. Objective: To identify differences in the number of relapses, inflammatory markers, outcomes and renal histology related to the types of ANCA. To analyze the implications of ANCA titers in prognosis. Method: A retrospective observational study in a Portuguese tertiary hospital. Results: There were no differences in the progression of renal function, histological pattern and initial treatment with regard to ANCA subtypes. As for the evaluated parameters, there were no significant differences according to the types of ANCA, except for mean CRP values within the normal range, which was 6.3±1.3 mg/L for MPO-ANCA and 12.4±10.14 mg/L for PR3-ANCA (p=0.04). We found that 66.7% of the MPO-ANCA-positive showed no relapses versus 40% in the case of PR3-ANCA-positive. There was no correlation between the ANCA titers at presentation, during remission, and in the last evaluation, and the number of relapses. Conclusion: PR3-ANCA patients have a mean CRP value within the normal range significantly higher than that of MPO-ANCA patients (p=0.04), which seems to reveal greater inflammatory activity in the first.

RESUMO Introdução: a vasculite associada aos anticorpos anticitoplasma de neutrófilos (ANCA) é uma doença autoimune que pode acometer vários órgãos, sendo o rim um dos mais afetados. Além dos ANCA serem marcadores de diagnóstico, foram também defendidos como marcadores de atividade. Recentemente as alterações genéticas encontradas entre as poliangeítes serina-protease 3 da proteinase (PR3)-ANCA ou mieloperoxidase (MPO)-ANCA levantam a possibilidade de diferenças imunopatogênicas e terapêuticas. Objetivos: identificar diferenças quanto a número de recidivas, marcadores inflamatórios, desfechos e histologia renal relativamente aos tipos de ANCA. Analisar implicações dos títulos de ANCA no prognóstico. Método: estudo retrospectivo observacional em hospital terciário português. Resultados: não se verificaram diferenças quanto à evolução da função renal, ao padrão histológico e ao tratamento inicial relativamente aos subtipos de ANCA. Nos parâmetros analíticos avaliados, não se verificaram diferenças significativas relativas aos tipos de ANCA, à exceção do valor médio de PCR no intervalo que foi de 6,3±1,3 mg/L nos MPO-ANCA e 12,4±10,14 mg/L nos PR3-ANCA (p=0,04). Verificamos que 66,7% dos MPO-ANCA positivos não apresentaram recidivas versus 40% dos PR3-ANCA positivos. Não se verificou nenhuma correlação entre os títulos de ANCA à apresentação, durante a remissão e na última avaliação com o número de recidivas. Conclusão: os indivíduos PR3-ANCA apresentaram um valor médio de PCR nos intervalos superior aos indivíduos MPO-ANCA (p=0,04), o que parece evidenciar uma maior atividade inflamatória nos primeiros.

Increased oxidative stress markers may be a promising indicator of risk for primary ovarian insufficiency: a cross-sectional case control study / Marcadores de estresse oxidativo aumentados podem ser um indicador de risco promissor para insuficiência ovariana primária: um estudo transversal caso-controle

PURPOSE: The aim of this study was to evaluate serum levels of inducible nitric oxide synthase (INOS), myeloperoxidase (MPO), total antioxidant status (TAS), and total oxidative status (TOS) in women with primary ovarian insufficiency (POI) and to compare them with healthy fertile women. We also examined the possible risk factors associated with POI.METHODS: This cross-sectional case control study was conducted in Zekai Tahir Burak Women's Health Education and Research Hospital. The study population consisted of 44 women with POI (study group) and 36 healthy fertile women (control group). In all patients, serum levels of INOS, MPO, TAS, and TOS were determined. INOS and MPO levels were measured by enzyme-linked immunosorbent assay whereas colorimetric method was used for evaluating TAS and TOS levels. Age, body mass index (BMI), obstetric history, smoking status, family history, comorbidities, sonographic findings, complete blood count values, C-reactive protein and baseline hormone levels were also analyzed. Student's t-test or Mann-Whitney U test was used to compare continuous variables between the groups; categorical data were evaluated by using Pearson χ2 or Fisher exact test, when appropriate. Binary logistic regression method was used to identify risk factors for POI.RESULTS: We found significantly elevated levels of INOS (234.1±749.5 versus133.8±143.0; p=0.005), MPO (3,438.7±1,228.6 versus 2,481.9±1,230.1; p=0.001), and TOS (4.3±1.4 versus 3.6±1.4; p=0.02) in the sera of the study group when compared to the BMI-age matched control group. However, difference in serum levels of TAS were not significant between the 2 groups (1.7±0.2 versus 1.6±0.2; p=0.15). Logistic regression method demonstrated that BMI <25 kg/m2, nulliparity, family history of POI, smoking, and elevated serum levels of INOS, MPO, and TOS were independent risk factors for POI.CONCLUSION: We found an increase in INOS, MPO, and TOS in women with POI. These serum markers may be promising in early diagnosis of POI. Further large-scale studies are required to determine whether oxidative stress markers have a role in diagnosing POI.

OBJETIVO: Avaliar os níveis séricos da sintetase nítrica induzível (INOS), da mieloperoxidase (MPO), do estado antioxidante total (EAT) e do estado oxidante total (EOT) em mulheres portadoras de insuficiência ovariana primária (IOP) e compará-las às mulheres férteis. Também examinamos os possíveis fatores de risco associados à IOP.MÉTODOS: Trata-se de estudo transversal caso-controle desenvolvido no Zekai Tahir Burak Women's Health Education and Research Hospital. A população de estudo abrangeu 44 mulheres portadoras de IOP (grupo de estudo) e 36 mulheres férteis hígidas (grupo controle). Em todas as pacientes, foram determinados os níveis séricos de INOS, MPO, EAT e EOT.Os níveis de INOS e MPO foram determinados com o uso do teste ELISA e os níveis de EAT e EOT foram determinados mediante método colorimétrico. Analisou-se também a idade, o índice de massa corporal (IMC), os antecedentes obstétricos, tabagismo, histórico familiar, comorbidades, achados sonográficos, valores completos do hemograma, proteína C-reativa e níveis hormonais basais. O teste t de Student ou o teste U de Mann-Whitney foi utilizado para comparar as variáveis contínuas entre os grupos; os dados categóricos foram avaliados pelo teste do χ2 de Pearson ou o teste exato de Fisher, conforme o caso. O método de regressão logística binária foi utilizado para identificar os fatores de risco para IOP.RESULTADOS: Encontramos níveis significativamente elevados de INOS (234,1±749,5 versus133,8±143,0; p=0,005), MPO (3.438,7±1.228,6 versus 2.481,9±1.230,1; p=0,001) e EOT (4,3±1,4 versus 3,6±1,4; p=0,02) nos soros do grupo estudo em relação ao grupo controle pareado por IMC e idade. Entretanto, as diferenças entre os níveis séricos de EAT nos dois grupos não foram significantes (1,7±0,2 versus 1,6±0,2; p=0,15). O método de regressão logística demonstrou que IMC <25 kg/m2, nuliparidade, histórico familiar de IOP, tabagismo e níveis séricos elevados de INOS, MPO e EOT foram fatores de risco independentes para IOP.CONCLUSÃO: Foram encontrados níveis aumentados de INOS, MPO e EOT em mulheres portadoras de IOP. Estes marcadores séricos podem ser promissores para o diagnóstico precoce de IOP. Novos estudos em larga escala são necessários para determinar se os marcadores de estresse oxidativo desempenham um papel no diagnóstico da IOP.

Effects of vitaiin c supplementation on the chronic phase of chagas iisease / Efeitos da suplementação de vitamina C na fase crônica da doença de Chagas

Introduction: In order to examine the effectiveness of vitamin C (ascorbic acid) in combating the oxidative insult caused by Trypanosoma cruzi during the development of the chronic phase of Chagas disease, Swiss mice were infected intraperitoneally with 5.0 × 104 trypomastigotes of T. cruzi QM1strain. Methods: Mice were given supplements of two different doses of vitamin C for 180 days. Levels of lipid oxidation (as indicated by thiobarbituric acid reactive substances-TBARS), total peroxide, vitamin C, and reduced glutathione were measured in the plasma, TBARS, total peroxide and vitamin C were measured in the myocardium and histopathologic analysis was undertaken in heart, colon and skeletal muscle. Results: Animals that received a dose equivalent to 500 mg of vitamin C daily showed increased production of ROS in plasma and myocardium and a greater degree of inflammation and necrosis in skeletal muscles than those that received a lower dose or no vitamin C whatsoever. Conclusion: Although some research has shown the antioxidant effect of vitamin C, the results showed that animals subject to a 500 mg dose of vitamin C showed greater tissue damage in the chronic phase of Chagas disease, probably due to the paradoxical actions of the substance, which in this pathology, will have acted as a pro-oxidant or pro-inflammatory. .

Introdução: Para verificar a eficácia da vitamina C em combater o insulto oxidativo causado pelo Trypanosoma cruzi durante a evolução da fase crônica da doença de Chagas, camundongos Swiss foram previamente infectados via intraperitoneal com 5.0 × 104 tripomastigotas da cepa QM1 de T. cruzi. Métodos: Camundongos foram suplementados com duas diferentes doses de vitamina C por 180 dias. Foram mensurados os níveis de peroxidação lipídica (indicado por substâncias reativas ao ácido tiobarbitúrico-TBARS), peróxido total, vitamina C, e glutationa reduzida no plasma e TBARS, peróxido total e vitamina C no miocárdio, e foi realizado o estudo histopatológico em coração, cólon e músculo esquelético. Resultados: Animais que receberam diariamente uma dosagem equivalente a 500 mg de vitamina C apresentaram aumento na produção de ROS e RNS no plasma e no miocárdio e maior grau de inflamação e necrose em músculo esquelético em comparação àqueles que receberam doses menores ou nenhuma vitamina C. Conclusão: Embora muitas pesquisas tenham mostrado o efeito antioxidante da vitamina C, nossos resultados mostraram que os animais que foram expostos a 500 mg de vitamina C apresentaram maior dano tecidual na fase crônica da doença de Chagas, provavelmente devido a ações paradoxais desta substância, onde nesta patologia, poderá agir como pró-oxidante ou pró-inflamatória. .

Protective effects of abdominal electroacupuncture on oxidative stress and inflammation due to testis torsion/detorsion in rats

PURPOSE: To evaluate the effects of acupuncture (Ac) and electroacupuncture (EAc) on oxidative stress and inflammation in testis torsion/detorsion (T/D) model in rats. METHODS: Thirty male Wistar rats were randomized into five groups. G1 Group (Sham) served as control. The remaining groups were submitted to spermatic cord torsion (720°) for 3 hours, followed by detorsion and reperfusion for 4 hours. Before detorsion G3, G4 and G5 rats were treated with Ac, EAc 2Hz and EAc 10 Hz, respectively, applied to acupoint Gulai (S-29) bilaterally under anesthesia for 5 minutes. Next, the testes were detorsioned and reperfused for 4 hours. Afterwards, blood samples and the right testis were collected for biochemical assays: reduced Glutathione (GSH), Malonaldehyde (MDA), Myeloperoxidase (MPO). RESULTS: EAc stimulation (2 and 10 Hz) promoted significant increase in concentrations of GSH in plasma and testis of G4-G5 rats, compared with G1. There was significant increase of tissue MDA in groups G4-G5 and plasma MDA in all groups, compared with G1. There was a significant reduction in MPO activity in groups G4-G5 compared with G1. CONCLUSION: Electroacupuncture stimulation (2 and 10 Hz) attenuates oxidative stress and inflammatory response in rats subjected to testicular torsion/detorsion. .

Oxidative stress and cellular immunity in patients with recurrent aphthous ulcers

Recurrent aphthous ulcer (RAU) is an inflammatory condition of the oral mucosa characterized by painful, well-circumscribed, single or multiple round or ovoid ulcerations. The exact etiologic factor(s) of these ulcerations are not yet understood. The objective of this study was to evaluate inflammatory processes and free radical metabolism of 25 patients with RAUs compared to 25 healthy controls. The levels of malondialdehyde (MDA) and glutathione (GSH) were determined by high-performance liquid chromatography. Tumor necrosis factor-alpha (TNF-α), interleukin-2 (IL-2), IL-10, and IL-12 were determined by ELISA. Nitric oxide (NO), myeloperoxidase (MPO), total antioxidant status (TAS), and total oxidant status (TOS) levels were measured spectroscopically in serum. The levels of MDA, GSH, TNF-α, IL-2, IL-12, MPO, and TOS, and oxidative stress index (OSI) were higher, and the levels of NO, IL-10, and TAS were lower in patients with RAU than in controls. Statistical analysis showed that GSH, TNF-α, IL-2, IL-10, and OSI differed significantly in patients with RAU compared to controls. These parameters have important roles in oxidant/antioxidant defense.

Positive correlttion between disease activity idex and matrix metalloproteinasses activity in a rat model of colitis / Correlação positiva entre índice de atividade de doença e metaloproteinase de matriz em modelo de colite em ratos

Context Inflammatory bowel disease, including ulcerative colitis and Crohn’s disease, comprising a broad spectrum of diseases those have in common chronic inflammation of the gastrointestinal tract, histological alterations and an increased activity levels of certain enzymes, such as, metalloproteinases. Objectives Evaluate a possible correlation of disease activity index with the severity of colonic mucosal damage and increased activity of metalloproteinases in a model of ulcerative colitis induced by dextran sulfate sodium. Methods Colitis was induced by oral administration of 5% dextran sulfate sodium for seven days in this group (n=10), whereas control group (n=16) received water. Effects were analyzed daily by disease activity index. In the seventh day, animals were euthanized and hematological measurements, histological changes (hematoxylin and eosin and Alcian Blue staining), myeloperoxidase and metalloproteinase activities (MMP-2 and MMP-9) were determined. Results Dextran sulfate sodium group showed elevated disease activity index and reduced hematological parameters. Induction of colitis caused tissue injury with loss of mucin and increased myeloperoxidase (P<0.001) and MMP-9 activities (45 fold) compared to the control group. Conclusions In this study, we observed a disease activity index correlation with the degree of histopathological changes after induction of colitis, and this result may be related mainly to the increased activity of MMP-9 and mieloperoxidase. .

Contexto Doenças inflamatórias intestinais, entre elas colite ulcerativa e doença de Crohn, compreendem um amplo espectro de doenças que apresentam em comum inflamação crônica do trato gastrointestinal, alterações histológicas e um aumento de atividade de determinadas enzimas, tais como, metaloproteinases. Objetivos Avaliar possível correlação do índice de atividade de doença em modelo de colite ulcerativa induzida por dextran sulfato de sódio com o grau de severidade de danos na mucosa colônica e aumento de atividade de metaloproteinases. Métodos Colite foi induzida por administração oral de dextran sulfato de sódio 5% durante sete dias no grupo (n = 10), enquanto que o grupo controle (n = 16) recebeu água. Efeitos foram analisados diariamente pelo índice de atividade de doença. No sétimo dia, os animais foram sacrificados e as medições hematológicas, alterações histológicas (hematoxilina e eosina e coloração de azul Alcian), mieloperoxidase e atividades de metaloproteinases (MMP-2 e MMP-9) foram determinados. Resultados Grupo dextran sulfato de sódio mostrou elevação no índice de atividade de doença e redução dos parâmetros hematológicos. A indução da colite causa lesão no tecido, com perda de mucina e aumento da mieloperoxidase (P<0,001) e as atividades MMP-9 (45 vezes) em comparação com o grupo de controle. Conclusões Neste estudo, observamos uma correlação do índice de atividade de doença com o grau de alterações histopatológicas após indução da colite por dextran sulfato de sódio, podendo associar este resultado ao aumento principalmente da atividade de MMP-9 e de mieloperoxidase. .

Effect of eccentric training on mitochondrial function and oxidative stress in the skeletal muscle of rats

The objective of the present study was to investigate the effects of eccentric training on the activity of mitochondrial respiratory chain enzymes, oxidative stress, muscle damage, and inflammation of skeletal muscle. Eighteen male mice (CF1) weighing 30-35 g were randomly divided into 3 groups (N = 6): untrained, trained eccentric running (16°; TER), and trained running (0°) (TR), and were submitted to an 8-week training program. TER increased muscle oxidative capacity (succinate dehydrogenase and complexes I and II) in a manner similar to TR, and TER did not decrease oxidative damage (xylenol and creatine phosphate) but increased antioxidant enzyme activity (superoxide dismutase and catalase) similar to TR. Muscle damage (creatine kinase) and inflammation (myeloperoxidase) were not reduced by TER. In conclusion, we suggest that TER improves mitochondrial function but does not reduce oxidative stress, muscle damage, or inflammation induced by eccentric contractions.

Mitigation of acute lipopolysaccharide-induced renal injury by hydrogen sulfide in adult male rats

Sepsis is one of the leading causes of acute kidney injury [AKI] and increases risk of death. Bused on the hemodynamic effects and anti-inflammatory properties of the hydrogen sulfide [H[2]S], this study aimed to examine its effects on renal damage using a rat model of lipopolysaccharide [LPS]-induced AKI where LPS promotes inflammation-mediated kidney damage. A total of forty adult male Wistar albino rats were included in the study. The rats were randomly divided into 4 groups: [I] control group was treated with saline. [2] H[2]S group received a single intravenous [i.v.] bolus of sodium hydrosulfide [NaHS] as H[2]S donor in ci dose of 0.2 mg/kg. [3] LPS group in which endoloxemic shock was induced through the intraperitoneal [i.p.] injection of 20 mg/kg LPS. [4] LPS H[2]S group received LPS with the same dose as the previous group, then 5 minutes later NaHS, in a single dose [0.2 mg/kg] was injected. Administration of NaHS as H[2]S donor in LPS + H[2]S group significantly abrogated kidney inflammation as evident by significant decrease of renal intercellular adhesion molecule- 1 [ICAM- 1], myeloperoxidase [MPO] and attenuated kidney cellular damage as observed by the increase of the Na -K- ATPase activity as compared with LPS group. These renoprotective effects were accompanied by improvement of hemodynamic with increase of the mean arterial blood pressure [MAP] via reduction of nitric oxide [NO] level. Kidney functions were also effectively enhanced where glomerular filtration rate [GFR], renal blood flow [RBF], filtration fraction [FF.], renal vascular resistance [RVR], urine flow rate and urinary sodium excretion [U[Na]V] were significantly increased while proteinuria, serum urea and serum creatnine were significantly decreased. Urinary kidney injury molecule-1 [KIM-1] which is a specific tubular biomarker was greatly attenuated. Consistent with these observations, H[2]S treatment significantly alleviated renal hitopatholgical changes of LPS-induced AKI. Taken together, our results indicated the enhanced renal inflamination during LPS-induced AKI and the improvement of renal hemodynamic and functions as well as suppression of both renal cellular damage and inflammation by H[2]S which may signify its renoprotective effects in septic AKI

Role of calcium in enhancing the activity and thermal stability of a new cationic peroxidase purified from euphorbia tirucalli latex

A new cationic peroxidase from Euphorbi and firucalli [pencil cactus] latex was purified to homogeneity using benzene fractionation, gel filtration and cation-exchange chromatography. The purified enzyme was found to be monomeric with a molecular weight of 44 kDa as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis [SDS-PAGE]. The purified enzyme had a broad specificity towards some phenolic substrates in the order of 2,2'-azino-bis [3-ethylbenzothiazoline-6-sulfonicacid] [ABTS] > guaiacol > 0-phenylenediamine > 4-aminoantipyrene, whereas no affinity towards ascorbic acid and o-dianisidine was recorded. The enzyme had pH and temperature optima at 7.0 and 40°C, respectively. Study of kinetic parameters demonstrated that ABTS had the highest affinity towards ELP, where K[m], F[max] and V[ms]/K[m] values were 0.503 mM, 500 U/assay and 994.04 U/mM, respectively. ELP was stable from 10°C up to 60°C and lost about 70% of its activity at 70°C. The thermal inactivation profile of ELP in absence of Ca[2+] is biphasic and characterized by a rapid decline in activity on exposure to heat, followed by a more gradual decrease in activity on continued exposure. However, the purified enzyme exhibited increased thermal stability in the presence of calcium ions. Furthermore, the activity of purified enzyme was enhanced by 550% in the presence of 15 mM CaCl[2], suggesting a pivotal role for Ca[2+] in conferring structural stability to the heme environment and in retaining the active site of ELP. Most of the examined metal ions [except for Ca and Mg] and compounds had differential inhibitory effects on ELP activity. In conclusion, a locally available plant [Euphorbia tirucalli] could be a potential candidate source for peroxidase, the most widely used enzyme in industrial and biomedical applications. In addition, calcium was found to be essential for enhancing enzymatic activity and thermal stability of the purified Euphorbia tirucalli latex peroxidase

Comparison of oxidative stress & leukocyte activation in patients with severe sepsis & burn injury.

Background & objectives: We evaluated pro- and anti-oxidant disturbances in sepsis and non-sepsis burn patients with systemic inflammatory response syndrome (SIRS). Adhesion molecules and inflammation markers on leukocytes were also analyzed. We hypothesized that oxidative stress and leukocyte activation markers can lead to the severity of sepsis. Methods: In 28 severe sepsis and 27 acute burn injury patients blood samples were collected at admission and 4 days consecutively. Oxidative stress markers: production of reactive oxygen species (ROS), myeloperoxidase, malondialdehyde and endogenous antioxidants: plasma protein sulphydryl groups, reduced glutathione, superoxide dismutase and catalase were measured. Flow cytometry was used to determine CD11a, CD14, CD18, CD49d and CD97 adhesion molecules on leukocytes. Procalcitonin, C-reactive protein, fibrinogen, platelet count and lactate were also analyzed. Results: Pro-oxidant parameters were significantly elevated in sepsis patients at admission, ROS intensity increased in burn patients until the 5th day. Endogenous antioxidant levels except catalase showed increased levels after burn trauma compared to sepsis. Elevated granulocyte activation and suppressed lymphocyte function were found at admission and early activation of granulocytes caused by increasing activation/migration markers in sepsis. Leukocyte adhesion molecule expression confirmed the suppressed lymphocyte and monocyte function in sepsis. Interpretation & conclusions: Severe sepsis is accompanied by oxidative stress and pathological leukocyte endothelial cell interactions. The laboratory parameters used for the evaluation of sepsis and several markers of pro- and antioxidant status were different between sepsis and non-sepsis burn patients. The tendency of changes in these parameters may refer to major oxidative stress in sepsis and developing SIRS in burns.

Diagnostic Performance of High-Sensitivity Troponin T, Myeloperoxidase, and Pregnancy-Associated Plasma Protein A Assays for Triage of Patients with Acute Myocardial Infarction / 대한진단검사의학회지

BACKGROUND: Early diagnosis is the cornerstone of management of acute myocardial infarction (AMI). We aimed to compare the diagnostic accuracy of high-sensitivity troponin T (hs-cTnT) with myeloperoxidase (MPO) and pregnancy-associated plasma protein A (PAPP-A) for early diagnosis of AMI in patients at the time of presentation to the emergency department (ED). METHODS: We enrolled 289 patients who presented at the ED of the National Institute of Heart Disease (NIHD) Rawalpindi, Pakistan, within 4 hr of onset of chest pain. Clinical assessment, electrocardiography (ECG), and angiography were carried out. Blood samples were collected at 0, 3, 6, and 12 hr. Analyses of plasma hs-cTnT, MPO, and PAPP-A were carried out using commercial kits. RESULTS: Out of 289 subjects who presented to the ED, we diagnosed 180 patients with coronary heart disease as having AMI (N=61) and 119 as without AMI (stable coronary artery disease, N=61; unstable angina, N=58). Compared to non-AMI patients, the patients with AMI had significantly higher levels (represented here as median [inter quartile range]) of plasma hs-cTnT (136 [39-370] vs. 12 [7-21] ng/L), MPO (906 [564-1,631] vs. 786 [351-1,299] pmol/L) and PAPP-A (5.78 [2.67-13.4] vs. 2.8 [1.8-4.9] mIU/L). Receiver operator characteristic curves (95% CI) for hs-cTnT (0.952 [0.909-0.978]) were significantly higher (P<0.001) than those for MPO (0.886 [0.830-0.929]) and PAPP-A (0.797 [0.730-0.854]), with AMI sensitivity and specificity percentages of 87% and 98% (hs-cTnT), 82% and 84% (MPO), and 65% and 87% (PAPP-A), respectively. CONCLUSIONS: The diagnostic performance of hs-cTnT was superior to that of MPO and PAPP-A for early triage and diagnosis of AMI among patients of coronary heart disease presenting with chest pain to the ED.

Diagnostic Performance of High-Sensitivity Troponin T, Myeloperoxidase, and Pregnancy-Associated Plasma Protein A Assays for Triage of Patients with Acute Myocardial Infarction / 대한진단검사의학회지

BACKGROUND: Early diagnosis is the cornerstone of management of acute myocardial infarction (AMI). We aimed to compare the diagnostic accuracy of high-sensitivity troponin T (hs-cTnT) with myeloperoxidase (MPO) and pregnancy-associated plasma protein A (PAPP-A) for early diagnosis of AMI in patients at the time of presentation to the emergency department (ED). METHODS: We enrolled 289 patients who presented at the ED of the National Institute of Heart Disease (NIHD) Rawalpindi, Pakistan, within 4 hr of onset of chest pain. Clinical assessment, electrocardiography (ECG), and angiography were carried out. Blood samples were collected at 0, 3, 6, and 12 hr. Analyses of plasma hs-cTnT, MPO, and PAPP-A were carried out using commercial kits. RESULTS: Out of 289 subjects who presented to the ED, we diagnosed 180 patients with coronary heart disease as having AMI (N=61) and 119 as without AMI (stable coronary artery disease, N=61; unstable angina, N=58). Compared to non-AMI patients, the patients with AMI had significantly higher levels (represented here as median [inter quartile range]) of plasma hs-cTnT (136 [39-370] vs. 12 [7-21] ng/L), MPO (906 [564-1,631] vs. 786 [351-1,299] pmol/L) and PAPP-A (5.78 [2.67-13.4] vs. 2.8 [1.8-4.9] mIU/L). Receiver operator characteristic curves (95% CI) for hs-cTnT (0.952 [0.909-0.978]) were significantly higher (P<0.001) than those for MPO (0.886 [0.830-0.929]) and PAPP-A (0.797 [0.730-0.854]), with AMI sensitivity and specificity percentages of 87% and 98% (hs-cTnT), 82% and 84% (MPO), and 65% and 87% (PAPP-A), respectively. CONCLUSIONS: The diagnostic performance of hs-cTnT was superior to that of MPO and PAPP-A for early triage and diagnosis of AMI among patients of coronary heart disease presenting with chest pain to the ED.

A Study of Oxidative Stress Parameters in Anti-Helicobacter Pylorus Immunoglobulin G Positive and Negative Gastric Cancer Patients

PURPOSE: Helicobacter pylorus (HP) is a Gram-negative spiral-shaped microaerophilic bacterium, which colonizes in the gastric mucosa of humans. The gastric human pathogen HP causes chronic gastritis and ulcers, and has a strong relationship with gastric cancer. The aim of this study was to determine advanced oxidation protein products (AOPP) levels, activities of myeloperoxidase (MPO) and catalase (CAT) in two groups. MATERIALS AND METHODS: For this aim, one group included 30 patients with gastric cancer (Group 1) and the other included 30 subjects with non-gastric cancer and Anti-HP immunoglobulin (Ig) G antibody positive (group 2). Anti-HP IgG antibody test values were found as positive in fifty percent of group 1 and all of the group 2 patients. RESULTS: Significantly increased AOOP levels were found in group 1 (p < 0.05) compared to group 2. There were no significant differences between the groups in regard to activities of MPO and CAT. In addition, AOPP level, MPO and CAT activities were similar among the Anti-HP IgG positive and negative subgroups of group 1 patients. CONCLUSION: The result of this study indicated that gastric cancer patients were characterized by increased protein oxidation, whereas there was no significant difference in oxidative stress parameters and antioxidant enzyme activity between the Anti-HP IgG positive and negative gastric cancer patients.

A reconstituted HDL containing V156K or R173C apoA-I exhibited anti-inflammatory activity in apo-E deficient mice and showed resistance to myeloperoxidase-mediated oxidation

It has been hypothesized that blood infusion of reconstituted HDL (rHDL) is a possible therapeutic strategy for the treatment of coronary artery disese. To compare short-term anti-inflammatory activity of wildtype (WT) apoA-I and point mutants, each rHDL containing WT, V156K, or R173C was infused into apo-E deficient atherosclerotic mice. Each rHDL was injected via the tail vein at a dosage of 120 mg/kg of body weight in 0.4 ml of tris-buffered saline (TBS), and blood was then collected at 24 and 48 h post-injection. Although regression activity was observed in each of the rHDL infused groups, a 30% reduction in the lipid-stained area of the aortic sinus was observed in the V156K and R173C-rHDL groups when compared to that of the WT-rHDL group, and this reduction was well correlated with an approximately 60% reduction in the accumulation of macrophages in the lesion area. Additionally, the groups that received the V156K and R173C-rHDL treatments showed smaller increases in the GOT, GPT, interleukin-6, myeloperoxidase (MPO) and lipid hydroperoxide (LPO) serum levels than those that received the WT-rHDL treatment. In addition, the strongest serum paraoxonase and ferric reducing ability was observed in the V156K and R173C-rHDL groups. In vitro nitration and chlorination of apoA-I by MPO treatment revealed that V156K-rHDL and R173C-rHDL were less susceptible to chlorination. Furthermore, rHDL treatment inhibited cellular uptake of oxidized LDL by macrophage cells and the production of proatherogenic species in culture media. In conclusion, blood infusions of the rHDLs exerted in vivo regression activity with anti-inflammatory and antioxidant activity in apo-E deficient mice and THP-1 cells, especially in those that were treated with V156K and R173C apoA-I.

Mieloperoxidase e doença arterial coronariana: da pesquisa à prática clínica / Myeloperoxidase and coronary arterial disease: from research to clinical practice

A mieloperoxidase (MPO) é uma enzima derivada de leucócitos que catalisa a formação de numerosas espécies reativas oxidantes. Além de integrantes da resposta imune inata, evidências têm comprovado a contribuição desses oxidantes para o dano tecidual durante inflamação. A MPO participa de atividades biológicas pró-aterogênicas relacionadas à evolução da doença cardiovascular, incluindo iniciação, propagação e as fases de complicação aguda do processo aterosclerótico. Dessa forma, a MPO e sua cascata inflamatória representam um alvo atrativo para investigação prognóstica e terapêutica na doença aterosclerótica cardiovascular. Nesta revisão, apresentamos o estado da arte no entendimento das ações biológicas às evidências clínicas da relação entre MPO e doença arterial coronariana. Vários estudos apontam para o efeito independente dos níveis de MPO na evolução da doença e ocorrência de eventos em pacientes com síndrome coronariana aguda. Entretanto, ainda não é consistente o valor preditivo adicional dos níveis de MPO na estratificação de risco cardiovascular para incorporá-la à prática clínica como sinalizadora de vulnerabilidade de placa. Estudos adicionais são necessários para confirmar seu papel nas diferentes formas de apresentação da cardiopatia isquêmica, além da padronização do ensaio, ponto fundamental para a transição desse marcador do ambiente de pesquisa para uso na rotina clínica.

Myeloperoxidase (MPO) is an enzyme derived of leukocytes that catalyze formation of numerous reactive oxidant species. Besides members of the innate host defense, evidences have been proving the contribution of these oxidants to tissue injury during inflammation. MPO participates in proatherogenic biological activities related to the evolution of cardiovascular disease, including initiation, propagation and acute complications of atherosclerotic process. Thereby, MPO and its inflammatory cascade represents an attractive target for prognostical investigation and therapeutics in atherosclerotic cardiovascular disease. In this review, we present the state of the art in the understanding of biological actions to clinical evidences of the relationship between MPO and coronary arterial disease. Several studies point to the independent effect of MPO levels in the evolution of disease and incidence of events in patients with acute coronary syndrome. However, the additional predictive value of MPO levels in the cardiovascular risk assessment, to incorporate it to the clinical practice as marker of plaque vulnerability, is still not consistent. Additional studies are necessary to confirm its role in the different forms of presentation of ischemic disease, besides the standardization of the assay, fundamental point for transition of this marker from research atmosphere to use in clinical routine: : from laboratory to clinical practice.

Predictive value of myeloperoxidase to identify high risk patients admitted to the hospital with acute chest pain / Valor preditivo da mieloperoxidase na identificação de pacientes de alto risco admitidos por dor torácica aguda

FUNDAMENTO: A mieloperoxidase (MPO) é uma enzima intensamente expressa diante da ativação leucocitária, com múltiplas ações aterogênicas, incluindo a oxidação do colesterol (LDL), e relacionada à instabilização da placa aterosclerótica. É preditora de eventos adversos em indivíduos sadios, coronariopatas ou em investigação de dor torácica. OBJETIVO: Analisar a contribuição da MPO na identificação de pacientes com dor torácica aguda, eletrocardiograma (ECG) sem elevação de segmento ST e com alto risco para eventos adversos intra-hospitalares. MÉTODOS: O nível sérico da MPO foi mensurado na admissão de pacientes com dor torácica aguda, ECG sem elevação de segmento ST e submetidos a protocolo estruturado de investigação. RESULTADOS: De uma coorte de 140 pacientes, 49 (35 por cento) receberam o diagnóstico de síndrome coronariana aguda, tendo sido estabelecido diagnóstico de infarto agudo do miocárdio (troponina I > 1,0 ng/ml) sem elevação de ST em 13 pacientes (9,3 por cento). O melhor ponto de discriminação da MPO para infarto agudo do miocárdio foi identificado em > 100 pM pela curva ROC (AUC = 0,662; IC 95 por cento = 0,532-0,793), que demonstrou elevada sensibilidade (92,3 por cento) e elevado valor preditivo negativo (98,1 por cento), embora com baixa especificidade (40,2 por cento). Na análise multivariada, a MPO mostrou-se a única variável independente para o diagnóstico de infarto agudo do miocárdio em evolução, com razão de chance de 8,04 (p = 0,048). CONCLUSÃO: Em pacientes com dor torácica aguda e sem elevação de ST, a MPO admissional elevada é importante ferramenta preditiva de eventos adversos intra-hospitalares, com razão de chance de oito vezes para o diagnóstico de infarto agudo do miocárdio.

BACKGROUND: Myeloperoxidase (MPO) is a highly expressed enzyme due to leukocyte activation, with multiple atherogenic actions, including LDL cholesterol oxidation, and is related to the instability of atherosclerotic plaque. It is a predictor of adverse events in healthy individuals, patients with heart disease or those undergoing chest pain investigations. OBJECTIVE: To analyze the contribution of MPO to identify patients with acute chest pain, non-ST elevation ECG and at high risk for in-hospital adverse events. METHODS: Patients presenting acute chest pain and a non-ST elevation ECG, were admitted to the hospital and submitted to serum MPO level measurements and a structured examination protocol. RESULTS: From a cohort of 140 patients, 49 (35 percent) were diagnosed with acute coronary syndrome, of which 13 patients (9.3 percent) were diagnosed with non-ST elevation acute myocardial infarction (AMI) (troponin I >1.0 ng/mL). The best MPO cut-off point for AMI was identified as >100 pM using the ROC curve (AUC=0.662; CI 95 percent=0.532-0.793) revealing elevated sensitivity (92.3 percent) and negative predictive value (98.1 percent), however with low specificity (40.2 percent). In the multivariate analysis, MPO proved to be the only independent variable to diagnose AMI in evolution, with an odds ratio of 8.04 (p=0.048). CONCLUSION: In patients with acute chest pain and no ST elevation, high MPO levels upon admission to the hospital are an important tool to predict in-hospital adverse events, with an odds ratio of eight for the diagnosis of AMI.

Niveles plasmáticos de mieloperoxidasa y proteína C reactiva en conejos machos en Nueva Zelanda expuestos a una dieta hiperlipidémica / Plasma concentration of myeloperoxidase and C reactive protein in male New Zealand rabbits, exposed to a hyperlipidemic diet

La Mieloperoxidasa (MPO) y la Proteína C Reactiva (PCR) han sido implicados en la fisiopatología de la aterosclerosis. El objetivo del presente estudio fue determinar las concentraciones plasmáticas de MPO y PCR y su relación con la formación de ateromas en conejos. Se estudiaron 23 conejos machos Nueva Zelanda: Grupo 1: conejarina y verdura; Grupo 2: Huevo y conejarina. El periodo experimental duró 13 semanas. Se determinó perfil lipídico por métodos enzimáticos, MPO por ELISA y PCR por turbidimetría en 0 13va semana. Se realizó estudio histológico de aorta. Los resultados revelaron que la PCR se elevó en el grupo 2 al final del estudio (p<0,05). No se observó diferencias en MPO en el grupo 2 en el estudio. En cuanto a los ateromas se evidenciaron lesiones tipo I y II en los conejos del grupo 2. En conclusión, se encontró que la PCR y no la MPO son marcadores de aterosclerosis según nuestras condiciones experimentales.

Myeloperoxidase (MPO) and C-reactive protein (CRP) have been implicated in atherosclerosis. The objective of the present study was to determine plasma concentration MPO and CRP and its relationship of formation of aortic lesions in rabbits. 23 male New Zealand rabbits were study: Group 1: “conejarina” (commercial rabbit food) and vegetables; Group 2: egg and conejarina. The experiment lasted 13 weeks. Lipid profile was done by enzymatic methods, MPO by ELISA, and PCR by turbidimetry in weeks 0 and 13. Histological study of rabbits’ aorta was done. Results revealed that in group 2 CRP increased at final study (p <0.05). No differences were observed in MPO values in the experiment. Regarding atheroma, group 2 presented type I and II lesions. In conclusion only CRP is marker of atherosclerosis according to our experimental conditions.