[Inhibitive effect of exogenous carbon monoxide-releasing molecules 2 on the activation of Janus kinase/signal transducer and activator of transcription pathway in sepsis].

Objective: To study the inhibitive effect of exogenous carbon monoxide-releasing molecules 2 (CORM-2) on the activation of Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway in sepsis.

Methods: RAW264.7 cells were divided into normal control group, LPS group (10 mg/mL LPS, the same concentration below), LPS + inactive CORM-2 (iCORM-2) group, LPS + 50 mmol/L CORM-2 group, and LPS + 100 mmol/L CORM-2 group. TNF-alpha level in the supernatant was determined with ELISA, and the phosphorylation levels of JAK1 and JAK3 were determined with Western blot. Thirty-five male BALB/c mice were divided into normal control group, cecal ligation and puncture (CLP) group, CLP + iCORM-2 (8.0 mg/kg) group and CLP + CORM-2 group (8.0 mg/kg) according to the random number table. Mice in CLP + CORM-2 group were treated the same as mice in CLP group except for administration of CORM-2 after CLP. The plasma levels of TNF-alpha, IL-1beta, and the phosphorylation levels of JAK1, JAK3 in liver tissue were determined with ELISA 24 hours post CLP. Data were processed with t test.

Results: Compared with that of normal control group [(1.9 +/- 0.3) pg/mL], the TNF-alpha level [(8.2 +/- 2.7) pg/mL, t = 2.844, P < 0.01] and phosphorylation levels of JAK1, JAK3 in LPS group increased significantly; while TNF-alpha levels in LPS + 50 mmol/L CORM-2 and LPS + 100 mmol/L CORM-2 groups decreased obviously as compared with that of LPS group [(5.7 +/- 1.4), (3.2 +/- 0.9) pg/mL, with t value respectively 2.104 and 2.363, P values all below 0.05], and it was the same with phosphorylation levels of JAK1, JAK3 in a dose-dependent manner. Compared with those of normal control group, plasma levels of TNF-alpha and IL-1beta and phosphorylation levels of JAK1, JAK3 in liver tissue significantly increased in CLP group (with t value respectively 2.916 and 2.796, and P values all below 0.05); while plasma levels of TNF-alpha and IL-1beta and the phosphorylation levels of JAK1, JAK3 in liver tissue decreased significantly in CLP + CORM-2 group (with t value respectively 2.115 and 2.398, and P values all below 0.05).

Conclusions: Exogenous CORM-2 can obviously inhibit the phosphorylation of JAKs molecules and then inhibit the activation of JAK/STAT signal pathway in sepsis, and decrease the expression of downstream cytokines to effectively prevent cascade reaction in the inflammatory response after severe infection.