RESUMO
Background:@#It is important to modulate the expression of glucocorticoids receptor (GR) in tress and maintain the immunity homeostasis in sepsis process. Rhubarb have been shown to have potential effects on anti-inflammatory and immune modulation. The present study was designed to investigate the effects of rhubarb on the expression of GR and cellular immunity in burn-induced septic rats.@*Methods:@#Sixty-six healthy male Sprague Dawley (SD) rats were randomized into sepsis group (n = 24), rhubarb group (n = 24), and control group (n = 18); each group were further randomized into 12, 24, and 72 h subgroups according to different time points. During onset of the sepsis model, the rats in the rhubarb group were infused with 50 mg/kg rhubarb powder dissolved into 1 mL saline through gastric tube, while sepsis and control groups were treated with saline. The binding activity of GR in liver cytosol and binding capacity of GR in peripheral blood leucocyte were analyzed by radiation ligands binding assay. The percentages of CD4+, CD8+,CD4+CD25+T cells, CD19+B cells as well as natural killer (NK) cells in the lymphocytes in peripheral blood were detected by flow cytometer. For assessing the differences among groups, one-way analysis of variance (ANOVA) with Scheffe multi-comparison techniques were employed. Comparisons between time-based measurements within each group were performed with ANOVA repeated measurement.@*Results:@#The binding activity of GR in liver cytosol and binding capacity of GR in peripheral blood leucocyte were significantly decreased in a time-dependent manner in sepsis group (t = 23.045, P < 0.01; t = 24.395, P < 0.05, respectively), which were increased in a time-dependent manner after rhubarb administration (t = 19.965, P < 0.05; t = 17.140, P < 0.05, respectively). Twelve hours after sepsis, the percentages of CD4+ T cells, CD4+/CD25+ T cell ratio, and CD19+ B cells in the peripheral blood were significantly increased in the sepsis group (t = -3.395, P < 0.01; t = 2.568, P < 0.05; t = 2.993, P < 0.05, vs. control mice, respectively). However, the percentage of NK cells in the peripheral blood were significantly decreased in the sepsis group (t = -2.022, P < 0.05, vs. control mice). Twelve hours after sepsis, the percentage of CD8+ T cells were significantly decreased in the peripheral blood in the sepsis group (t = -2.191, P < 0.05, vs. control mice) and were significantly increased in the rhubarb group (t = 2.953, P < 0.05, vs. sepsis mice). Seventy-two hours after sepsis, the ratio of CD4+/CD25+ T cell in peripheral blood were significantly increased in the sepsis group (t = 2.508, P < 0.05, vs. control mice) while were significantly decreased in the rhubarb group (t = 3.378, P < 0.05, vs. control mice). Furthermore, the percentages of CD19+ B cell in peripheral blood were significantly decreased at 72 h in the rhubarb group (t = 2.041, P < 0.05 vs. sepsis group).@*Conclusions:@#Rhubarb might play potential anti-inflammatory and immunomodulatory roles in the sepsis processes.
RESUMO
Objective To investigate the effects of rhubarb on the expression of glucocorticoids receptor (GR)and peripheral blood lymphocytes in burning-induced septic rats. Methods Sixty-six male healthy Sprague-Dawley(SD)rats were randomly divided into sham operated control group(n=18),sepsis model group(n=24) and rhubarb treatment group(n=24),each group was further randomly divided into 12,24 and 72 hours subgroups according to different time points. The model of scald sepsis was replicated by scald injury induced by boiling water at the rat back accounting for 30% total body surface area(Ⅲ grade of scald),and administration of endotoxin (5 mg/kg)into the peritoneal cavity 12 hours after scald injury. After the successful establishment of septic models, the rats in the rhubarb treatment group were immediately infused with 50 mg/kg rhubarb powder dissolved in 1 mL saline through a gastric tube,while the rats in sham operated control group and sepsis model group received saline by the same way as a substitute for rhubarb. The the binding capacity of GR of peripheral blood leucocyte and binding activity of GR of hepatocyte were analyzed by radiation ligands binding assay. The CD4+,CD8+as well as CD4+/CD8+ ratio in peripheral blood lymphocytes were detected by flow cytometer. Results The binding capacity of GR of peripheral blood leucocyte and binding activity of GR of hepatocyte were significantly decreased in a time-dependent manner in sepsis model group compared to those of the sham operated control group,while in the rhubarb treatment group they were increased in a time-dependent manner after interference of rhubarb, and they were higher than those in the model group at the same time points〔leukocyte GR binding capacity (locus/cell)at 12,24,72 hours :1 515.38±300.44,1 859.63±258.26,1 890.50±307.88 vs. 1 122.63±225.39, 1 008.88±150.41,724.38±91.19;hepatocyte GR binding capacity(fmol/mg):210.19±26.26,258.01±20.98, 283.38±38.21 vs. 153.11±30.07, 129.83±26.89, 94.08±14.30, all P<0.01〕. Compared with the sham operated control group,the CD4+ and CD8+ were decreased in various degrees at 12 hours and 24 hours in the septic group, at 24 hours the differences being statistically significant (P<0.01 and P<0.05). CD4+/CD8+ratios were decreased significantly at all time points,the differences were statistically significant at 24 hours and 72 hours(both P<0.01). The CD4+ T cell and CD4+/CD8+ ratio at all the time points were increased at various degrees in the rhubarb treatment group,and the differences from those in the sepsis model group at 24 hours and 72 hours were statistically significant (1.58±0.69, 1.56±0.49 vs. 1.02±0.41, 1.01±1.68, both P<0.01). Conclusion Rhubarb can modulate the binding capacity of GR of peripheral blood leucocyte and the binding activity of GR of hepatocyte,and via its influence on the number of peripheral leucocytes,the immune dysfunction in the sepsis processes is improved.