Effect of Physical Training on Exercise-Induced Inflammation and Performance in Mice.

Acute exercise increases the amount of circulating inflammatory cells and cytokines to maintain physiological homeostasis. However, it remains unclear how physical training regulates exercise-induced inflammation and performance. Here, we demonstrate that acute high intensity exercise promotes an inflammatory profile characterized by increased blood IL-6 levels, neutrophil migratory capacity, and leukocyte recruitment to skeletal muscle vessels. Moreover, we found that physical training amplified leukocyte-endothelial cell interaction induced by acute exercise in skeletal muscle vessels and diminished exercise-induced inflammation in skeletal muscle tissue. Furthermore, we verified that disruption of the gp-91 subunit of NADPH-oxidase inhibited exercise-induced leukocyte recruitment on skeletal muscle after training with enhanced exercise time until fatigue. In conclusion, the training was related to physical improvement and immune adaptations. Moreover, reactive oxygen species (ROS) could be related to mechanisms to limit aerobic performance and its absence decreases the inflammatory response elicited by exercise after training.

Treatment with Apocynin Limits the Development of Acute Graft-versus-Host Disease in Mice.

Graft-versus-host disease (GVHD) is the most serious complication limiting the clinical utility of allogeneic hematopoietic stem cell transplantation (HSCT), in which lymphocytes of donors (graft) are activated in response to the host antigen. This disease is associated with increased inflammatory response through the release of inflammatory mediators such as cytokines, chemokines, and reactive oxygen species (ROS). In this study, we have evaluated the role of ROS in GVHD pathogenesis by treatment of recipient mice with apocynin (apo), an inhibitor of intracellular translocation of cytosolic components of NADPH oxidase complex. The pharmacological blockade of NADPH oxidase resulted in prolonged survival and reduced GVHD clinical score. This reduction in GVHD was associated with reduced levels of ROS and TBARS in target organs of GVHD in apocynin-treated mice at the onset of the mortality phase. These results correlated with reduced intestinal and liver injuries and decreased levels of proinflammatory cytokines and chemokines. Mechanistically, pharmacological blockade of the NADPH oxidase was associated with inhibition of recruitment and accumulation of leukocytes in the target organs. Additionally, the chimerism remained unaffected after treatment with apocynin. Our study demonstrates that ROS plays an important role in mediating GVHD, suggesting that strategies aimed at blocking ROS production may be useful as an adjuvant therapy in patients subjected to bone marrow transplantation.

Avaliação da interleucina 3 como marcador prognóstico na sepse / Role of interleukin-3 as a prognostic marker in septic patients

RESUMO Objetivo: Avaliar a acurácia dos níveis de interleucina 3 para predizer prognóstico em pacientes sépticos. Métodos: Conduzimos uma coorte prospectiva que incluiu pacientes adultos internados em unidade de terapia intensiva, que apresentassem sepse ou choque séptico iniciados há até 48 horas. Mediram-se os níveis séricos de interleucina 3 quando da inclusão (dia 1) e nos dias 3 e 7. O desfecho primário analisado foi a mortalidade hospitalar por qualquer causa. Resultados: Foram incluídos 120 pacientes. Os níveis séricos de interleucina 3 dosados à inclusão foram significativamente mais elevados em pacientes que faleceram em comparação aos que sobreviveram à internação hospitalar (91,2pg/mL versus 36pg/mL; p = 0,024). Em modelo de sobrevivência de Cox com inclusão de idade e valores sequenciais de SOFA, os níveis de interleucina 3 mensurados na inclusão mantiveram-se independentemente associados à mortalidade hospitalar (HR 1,032; IC95% 1,010 - 1,055; p = 0,005). Em curva Característica de Operação do Receptor construída para investigação adicional da acurácia da interleucina 3 na predição do prognóstico, encontrou-se área sob a curva de 0,62 (IC95% 0,51 - 0,73; p = 0,024) para mortalidade hospitalar. Valores iniciais de interleucina 3 acima de 127,5pg/mL mostraram-se significativamente associados à mortalidade hospitalar (p = 0,019; OR = 2,97; IC95% 1,27 - 6,97; p = 0,019), entretanto com baixo desempenho (especificidade de 82%, sensibilidade de 39%, valor preditivo positivo de 53%, valor preditivo negativo de 72%, razão de verossimilhança negativa de 0,73 e razão de verossimilhança positiva de 2,16). Conclusão: Níveis elevados de interleucina 3 mostraram-se independentemente associados à mortalidade hospitalar em pacientes sépticos, entretanto com baixo desempenho clínico.

ABSTRACT Objective: To evaluate the accuracy of IL-3 to predict the outcome of septic patients. Methods: Prospective cohort study with adult patients in an intensive care unit with sepsis or septic shock diagnosed within the previous 48 hours. Circulating IL-3 levels were measured upon inclusion (day 1) and on days 3 and 7. The primary outcome was hospital mortality. Results: One hundred and twenty patients were included. Serum levels of IL-3 on day 1 were significantly higher among patients who died than among patients who survived the hospital stay (91.2pg/mL versus 36pg/mL, p = 0.024). In a Cox survival model considering the IL-3 levels at inclusion, age and sequential SOFA, IL-3 values remained independently associated with mortality (HR 1.032; 95%CI 1.010 - 1.055; p = 0.005). An receiver operating characteristic curve was built to further investigate the accuracy of IL-3, with an area under the curve of 0.62 (95%CI 0.51 - 0.73; p = 0.024) for hospital mortality. A cutoff initial IL-3 value above 127.5pg/mL was associated with hospital mortality (OR 2.97; 95%CI: 1.27 - 6.97; p = 0.0019) but with a low performance (82% for specificity, 39% for sensibility, 53% for the positive predictive value, 72% for the negative predictive value, 0.73 for the negative likelihood and 2.16 for the positive likelihood ratio). Conclusion: Higher levels of IL-3 are shown to be independently associated with hospital mortality in septic patients but with poor clinical performance.

Role of interleukin-3 as a prognostic marker in septic patients. / Avaliação da interleucina 3 como marcador prognóstico na sepse.

OBJECTIVE: To evaluate the accuracy of IL-3 to predict the outcome of septic patients. METHODS: Prospective cohort study with adult patients in an intensive care unit with sepsis or septic shock diagnosed within the previous 48 hours. Circulating IL-3 levels were measured upon inclusion (day 1) and on days 3 and 7. The primary outcome was hospital mortality. RESULTS: One hundred and twenty patients were included. Serum levels of IL-3 on day 1 were significantly higher among patients who died than among patients who survived the hospital stay (91.2pg/mL versus 36pg/mL, p = 0.024). In a Cox survival model considering the IL-3 levels at inclusion, age and sequential SOFA, IL-3 values remained independently associated with mortality (HR 1.032; 95%CI 1.010 - 1.055; p = 0.005). An receiver operating characteristic curve was built to further investigate the accuracy of IL-3, with an area under the curve of 0.62 (95%CI 0.51 - 0.73; p = 0.024) for hospital mortality. A cutoff initial IL-3 value above 127.5pg/mL was associated with hospital mortality (OR 2.97; 95%CI: 1.27 - 6.97; p = 0.0019) but with a low performance (82% for specificity, 39% for sensibility, 53% for the positive predictive value, 72% for the negative predictive value, 0.73 for the negative likelihood and 2.16 for the positive likelihood ratio). CONCLUSION: Higher levels of IL-3 are shown to be independently associated with hospital mortality in septic patients but with poor clinical performance.

OBJETIVO: Avaliar a acurácia dos níveis de interleucina 3 para predizer prognóstico em pacientes sépticos. MÉTODOS: Conduzimos uma coorte prospectiva que incluiu pacientes adultos internados em unidade de terapia intensiva, que apresentassem sepse ou choque séptico iniciados há até 48 horas. Mediram-se os níveis séricos de interleucina 3 quando da inclusão (dia 1) e nos dias 3 e 7. O desfecho primário analisado foi a mortalidade hospitalar por qualquer causa. RESULTADOS: Foram incluídos 120 pacientes. Os níveis séricos de interleucina 3 dosados à inclusão foram significativamente mais elevados em pacientes que faleceram em comparação aos que sobreviveram à internação hospitalar (91,2pg/mL versus 36pg/mL; p = 0,024). Em modelo de sobrevivência de Cox com inclusão de idade e valores sequenciais de SOFA, os níveis de interleucina 3 mensurados na inclusão mantiveram-se independentemente associados à mortalidade hospitalar (HR 1,032; IC95% 1,010 - 1,055; p = 0,005). Em curva Característica de Operação do Receptor construída para investigação adicional da acurácia da interleucina 3 na predição do prognóstico, encontrou-se área sob a curva de 0,62 (IC95% 0,51 - 0,73; p = 0,024) para mortalidade hospitalar. Valores iniciais de interleucina 3 acima de 127,5pg/mL mostraram-se significativamente associados à mortalidade hospitalar (p = 0,019; OR = 2,97; IC95% 1,27 - 6,97; p = 0,019), entretanto com baixo desempenho (especificidade de 82%, sensibilidade de 39%, valor preditivo positivo de 53%, valor preditivo negativo de 72%, razão de verossimilhança negativa de 0,73 e razão de verossimilhança positiva de 2,16). CONCLUSÃO: Níveis elevados de interleucina 3 mostraram-se independentemente associados à mortalidade hospitalar em pacientes sépticos, entretanto com baixo desempenho clínico.

Inhibition of 5-lipoxygenase alleviates graft-versus-host disease.

Leukotriene B4 (LTB4), a proinflammatory mediator produced by the enzyme 5-lipoxygenase (5-LO), is associated with the development of many inflammatory diseases. In this study, we evaluated the participation of the 5-LO/LTB4 axis in graft-versus-host disease (GVHD) pathogenesis by transplanting 5-LO-deficient leukocytes and investigated the effect of pharmacologic 5-LO inhibition by zileuton and LTB4 inhibition by CP-105,696. Mice that received allogeneic transplant showed an increase in nuclear 5-LO expression in splenocytes, indicating enzyme activation after GVHD. Mice receiving 5-LO-deficient cell transplant or zileuton treatment had prolonged survival, reduced GVHD clinical scores, reduced intestinal and liver injury, and decreased levels of serum and hepatic LTB4 These results were associated with inhibition of leukocyte recruitment and decreased production of cytokines and chemokines. Treatment with CP-105,696 achieved similar effects. The chimerism or the beneficial graft-versus-leukemia response remained unaffected. Our data provide evidence that the 5-LO/LTB4 axis orchestrates GVHD development and suggest it could be a target for the development of novel therapeutic strategies for GVHD treatment.