Tumor necrosis factor receptor-associated factor 1 (TRAF1), an adapter in signal transduction, is involved in immunity and in apoptotic processes in various cell types. However, little is known about its function and the molecular mechanism of its activation during liver injury. This study tested the hypothesis that TRAF1 is a mediator of cell injury after hepatic ischemia/reperfusion injury (I/R). In a mouse hepatic I/R injury model, we found that TRAF1 expression was highly induced. TRAF1 deficiency was liver protective, whereas sustained TRAF1 overexpression aggravated liver injury in response to hepatic I/R injury. Mechanistic studies demonstrated that a deficiency of TRAF1 in cultured hepatocytes led to the inhibition of NF-κB-mediated inflammatory responses, suppression of the ASK/JNK pro-death pathway and promotion of cellular regeneration capacity. In contrast, the converse occurred in hepatocyte-specific TRAF1 transgenic mice. TRAF1 activated the ASK1/JNK pathway and promoted hepatic injury. Our study demonstrates that TRAF1 is a crucial early mediator of hepatic I/R injury and suggests that TRAF1 may be a potential gene therapy target for the treatment of liver injury.

ABSTRACT.To study the role of boswellic acid in reducing asthma phenotype severity and the relationship between the expression of pSTAT6 and GATA3, thirty-six mice were randomly divided into normal control group, asthma group, and boswellic acid group (treatment group). The asthma model was established through an intraperitoneal injection of sensitization liquid (0.15 mL aluminum hydroxide gel at 88.67 mg/ mL and 0.05 mg ovalbumin). pSTAT6 and GATA3 expression levels in peripheral blood were detected by reverse transcription-polymerase chain reaction and Western blot analysis. pSTAT6 and GATA3 gene expressions in the asthmatic group were significantly higher than in the normal control group; they were markedly lower in the treatment group than the asthma group, and there was no significant difference when compared with the normal control group. The pSTAT6 expressions in the asthma, control and treatment groups were 2.256 ± 0.125, 0.524 ± 0.210, and 0.897 ± 0.134 at gray level, respectively. The GATA3 expressions in the asthma, control, and treatment groups were 3.521 X. Zhou et al. 7464©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 14 (3): 7463-7468 (2015) ± 0.631, 0.435 ± 0.136, and 0.743 ± 0.149 at gray level, respectively. pSTAT6 and GATA3 expression levels were similar in the treatment and control groups. GATA3 expression had a positive correlation with pSTAT6 expression. Boswellic acid may improve asthma symptoms by inhibiting pSTAT6 expression, which consequently reduces GATA3 expression.