Effect of adiponectin on early and late cytokine expression in LPS-induced septic rat

Abstract

Objective To investigate the effect of adiponectin on early and late cytokine expression in lipopolysaccharide (LPS) induced septic rats. Methods Ninety -six Wistar male rats were randomly divided into 4 groups: control group (C group), model group (LPS group), early adiponectin treatment group (APN+LPS group), late adiponectin treatment group (LPS+APN group). At 4, 24, 48 and 72 hours after administration of LPS or NS, six rats were randomly sacrificed in each group. Serum samples and the lung tissue samples were collected. The levels of tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6) in plasma were determined by enzyme linked immunosorbent assay (ELISA). Lung tissues were sampled. The expression of high mobility group box 1 (HMGB1) mRNA in the lung tissue were detected by Quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR) with GAPDH as an internal standard. The survival curves in 4 groups were drawn. Results The levels of TNF-α (17.13±1.04) vs. (0.45±0.29) and IL-6 (201.98±1.25) vs(9.81±0.69) in plasma in LPS group were higher than those in C group at 4 hours (P<0.05), the trend of whichlast for 24 hours. TNF-a and IL-6 levels of both APN+LPS group and LPS+APN group were reduced as compared with LPS group(P<0.05). The HMGB1mRNA expression level in lung tissue was measurable at 24 hours in LPS group(2.36±0.25,P<0.05), which maintained a high level up to 48 hours after administration of LPS. The HMGB1 mRNA expression level in both APN+LPS group and LPS+APN group were decreased as compared with that of LPS group (1.41 ±0.42 vs 2.36±0.25; 1.42±0.38 vs 2.36±0.25, respectively,P<0.05).The survival rate of rats in both APN+LPS group and LPS+APN group were higher than that of LPS group (70% vs. 30%; 60% vs. 30%, P<0.05). Conclusion Adiponectin can significantly raise the survival rate of septic rats. It also can inhibit the early and late cytokines expression in LPS induced septic rats. Key words: HMGB1; TNF-α; IL-6; Adiponectin; Endotoxin; Sepsis