ag-490 and Multiple-Organ-Failure

Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway plays an important role in sepsis, transducing a multitude of inflammatory signals. To date, knowledge of JAK/STAT pathway in sepsis is limited. This study was to investigate the potential role of JAK/STAT pathway in mediating multiple organ damage and mortality in septic rats. Our data showed that inhibition of JAK2/STAT3 attenuated cecal ligation and puncture-induced multiple organ damage and mortality in 48 hours in rats.. A total of 98 male Wistar rats were randomly divided into 4 groups as follows: (1) normal control group (n = 10); (2) cecal ligation and puncture (CLP) group (n = 40), which was further divided into 2, 6, 24, 48-hour post-CLP groups; (3) AG490 (8.0 mg/kg, Calbiochem, La Jolla, CA) treatment group (n = 24), which was further divided into 2, 6, 24, 48-hour post-CLP groups; (4) rapamycin (0.4 mg/kg, Calbiochem, Calbiochem, La Jolla, CA) treatment group (n = 24), which was further divided into 2, 6, 24, 48-hour post-CLP groups; CLP was performed to induce experimental sepsis. AG490 (8 mg/kg) or rapamycin (0.4 mg/kg) was injected subcutaneously 0.5 hour before CLP in respective group. Animals were killed at destined time after CLP (not including the death rate observation group), and specimens of serum, liver, and lungs were harvested and stored in liquid nitrogen for subsequent analyses. In an additional experiment, 88 animals were randomly divided into three groups to compare the survival rate, including CLP group (n = 40), AG490 treatment group (8 mg/kg, n = 24), and rapamycin treatment group (0.4 mg/kg, n = 24). Mortality of rats in each group was recorded up to 48 hours after the procedure.. After CLP challenge, myeloperoxidase (MPO), aspartate transaminase, and alanine aminotransferase levels, as well as activation of JAK2 and STAT3, were markedly increased. Administration of AG490 or rapamycin significantly decreased activation of JAK2 and STAT3, as well as high mobility group box-1 protein, MPO, alanine aminotransferase levels (p < 0.05 or p < 0.01). In addition, treatment with AG490 or rapamycin significantly improved the 48-hour survival rate from 37.5% (15 of 40) to 66.7% (16 of 24) and 70.8% (17 of 24), respectively (both p < 0.05).. JAK2/STAT3 pathway might play a role in the development of multiple organ damage in septic rats, which suggested a potential strategy to control sepsis.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Cecum; Drug Administration Schedule; Enzyme Inhibitors; HMGB1 Protein; Janus Kinase 2; Male; Multiple Organ Failure; Peroxidase; Rats; Rats, Wistar; Signal Transduction; Sirolimus; STAT3 Transcription Factor; Survival Rate; Tyrphostins

Tyrphostins, derivatives of benzylidene malononitrile are recognized as tyrosine kinase inhibitors that have been applied in some models of acute inflammatory conditions, like LPS and zymosan-induced shock. In the present study, we have investigated the effects of tyrphostin AG-490, on the development of multiple organ failure induced by i.p. injection of zymosan (1 mg/g body weight) in mice. Organ dysfunction and systemic inflammation was estimated 24 h after zymosan administration. Treatment of mice with AG-490 (dose, 5 mg/kg i.p. simultaneously with zymosan) decreased the number of cells and the level of NO in the peritoneal lavage. The substance attenuated the elevation of creatinine (indicator of renal failure), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and bilirubin (indicators for liver dysfunction) and prevented the accelerated coagulation time. The injection of zymosan resulted in a substantial increase in the serum level of TNF-alpha and IL-6, which was strongly inhibited by AG-490. Tyrphostin abolished the expression of iNOS and TNF-alphaR in the liver. Moreover, immunohistochemistry of liver showed decreased phosphorylation of Stat1 and Stat3. In conclusion, the administration of tyrphostin AG-490 in zymosan-induced nonseptic shock significantly improved the rate of survival and lead to less exerted signs of multiple organ failure.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Bilirubin; Creatinine; Inflammation; Interleukin-6; Macrophages; Male; Mice; Multiple Organ Failure; Nitric Oxide; Nitric Oxide Synthase Type II; Protein Kinase Inhibitors; STAT Transcription Factors; Tumor Necrosis Factor-alpha; Tyrphostins; Whole Blood Coagulation Time; Zymosan