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@#<b>Objective</b> To investigate the synergistic protective effects of WR-2721 combined with lentinan and cytokines against radiation damage in mice, and to provide a new treatment for acute radiation injury. <b>Methods</b> Seventy Institute of Cancer Research mice were divided into seven groups: a control group, a model group, WR-2721 group, Lentinan & cytokine group, WR-2721 & Lentinan group, WR-2721 & cytokine group and WR-2721 & Lentinan & cytokine group. All groups except the control group were irradiated with <sup>60</sup>Co γ-rays at a dose rate of 0.8 Gy/min and a cumulative dose of 5.0 Gy. The mice were sacrificed by cervical dislocation 14 d after irradiation to measure their spleen index, thymus index, and serum levels of superoxide dismutase (SOD), malondialdehyde (MDA), interleukin-11 (IL-11), and tumor necrosis factor-alpha (TNF-α). <b>Results</b> For the mice treated with WR-2721, lentinan, and cytokines, the spleen index was 7.33 ± 2.84, the thymus index was 1.70 ± 0.30, the serum SOD level was 114.0 ± 8.3, the MDA level was 7.33 ± 1.16, the IL-11 level was 155.8 ± 49.4, and the TNF-α level was 174.0 ± 37.8. All these indicators except the spleen index in the combination group significantly differed from those of the model group (<i>P</i> < 0.05 or 0.01), indicating the combined treatment promoted recovery from radiation damage. <b>Conclusion</b> WR-2721 combined with lentinan and cytokines has significant synergistic protective effects, which is a promising treatment for acute radiation injury.
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Objective:To investigate the effect of melatonin (MEL) influence on lipopolysaccharide (LPS)-induced long-term anxiety-like behavior and activation of astrocytes in septic neonatal rats.Methods:Sprague-Dawley rats were randomly(random number) assigned to the control group, LPS group and LPS+MEL group. Sepsis model was intraperitoneally injected with LPS (1 mg/kg), and neonatal rats in the MEL group were administered with MEL (10 mg/kg) 30 min after LPS injection. At different time points after injection, rats in each group were divided into three subgroups: 3 d, 7 d and 28 d. The expression of GFAP and TNF-α in the corpus callosum was detected by immunofluorescence staining and Western blot. Open-field test was applied to observe anxiety-like behaviors. In vitro, cultured neonatal SD rat astrocytes were divided into the control group, LPS group, LPS+MEL group, and LPS+MEL+luzindole group. Immunofluorescence staining was used to observe the expression of GFAP and TNF-α. Expression of GFAP, TNF-α, p-NF-κBp65, NF-κBp65 protein in astrocytes were assessed by Western blot. RT-qPCR was used to investigate the mRNA expression of GDNF and BDNF. One-way ANOVA and two-way ANOVA were used for comparison of multiple groups of variables. A P<0.05 was considered statistically significant. Results:LPS reduced the duration of movement in the central area and distance in the central area/total distance in open-field test, while melatonin evidently reversed the LPS-induced anxiety-like behavior. Compared with the LPS group, the expressions of GFAP and TNF-α were significantly decreased in the corpus callosum at 3 d and 7 d in the MEL group ( P< 0.05). Compared with the LPS group, MEL could significantly decrease the expression of GFAP, TNF-α and p-NF-κBp65 in astrocytes ( P< 0.05), which could be blocked by Luzindole. In addition, compared with the LPS group, MEL pretreatment could reverse the down regulation of GDNF and BDNF induced by LPS ( P<0.05). Conclusions:MEL can relieve LPS-induced long-term anxiety-like behavior in septic neonatal rats. The mechanism may be related to the inhibition of astrocyte activation and inflammatory reaction through NF - κ B pathway.
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Objective:To investigate the effect of melatonin on oligodendrocyte maturation and differentiation in corpus callosum of septic neonatal rats induced by systemic lipopolysaccharide (LPS) injection.Methods:Sprague-Dawley rats were randomly allocated into the control group, septic experimental group, and melatonin group. In the septic experimental group, rats were intraperitoneally administrated with lipopolysaccharide (LPS) (1 mg/kg). In the melatonin group, melatonin was intraperitoneally administered (10 mg/kg) at 0.5 h after LPS injection. The expression level of IL-6, olig1, olig2, and the MAG protein were detected by Western blot at different time points in the three groups. BV-2 cells were used in vitro. For drug administration, the effect of LPS, melatonin and melatonin receptor antagonist, luzindole, on IL-6 expression in BV-2 microglia cell was determined by Western blot. The medium of BV2 cell were collected to treat primary OPCs. The expression level of olig1, olig2 and MAG protein in primary OPCs were detected by Western blot. SPSS 20.0 statistical software was used for analysis, and the data were analyzed by one-way ANOVA and two-way ANOVA. Differences were considered to be statistically significantly if P<0.05. Result:Compared with the LPS group, the expression of IL-6 was significantly decreased in the corpus callosum at 6 h, l d, and 3 d in the melatonin group ( P<0.05). The expression of olig1, olig2 and MAG protein were increased at day 7, 14, and 28 in the melatonin group compared with the LPS group ( P<0.05). In vitro the expressions of IL-6 was significantly increased after LPS treatment ( P<0.05), but was decreased in the LPS+melatonin treatment group ( P<0.05). After treatment with melatonin receptor inhibitor, luzindole, the expressions level of IL-6 was increased ( P<0.05). The expression of olig1, olig2 and MAG protein were decreased with conditioned medium in the LPS BV2 cell group than the control group in the primary OPCs ( P<0.05). However, those were increased with conditioned medium in the LPS+melatonin BV2 cell group than the LPS group ( P<0.05). Conclusions:Melatonin may inhibit the inflammation response in the corpus callosum through its receptor, and may promote the maturation and differentiation of oligodendrocyte, suggesting that melatonin may have therapeutic effect on neuroinflammation and axonal hypomyelination on PWM in septic neonatal rats.
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Objective To investigate the effect of interleukin-1β (IL-1β) on the expression of synaptic protein SNAP-25 in the hippocampus in septic neonatal rat induced by systemic lipopolysaceharide (LPS) injection.Methods Sprague-Dawley (SD) rats were randomly divided into two groups:control group and sepsis group.The rat model of sepsis was produced by intraperitoneal injection of 1 mg/kg LPS,and rats in the control group were injected with an equal volume of 0.01 mol/L phosphate buffered saline (PBS).The expression levels of IL-1β and IL-1R1 in the hippocampus at 1,2 and 3 d,and synaptosomal-associated protein 25 (SNAP-25) at 7,14 and 24 d after LPS intraperitoneal injection were detected by Western blot.After cultured for 24 h,primary hippocampal neurons were divided into four groups including the control group,IL-1β (40 ng/mL) treatment group,IL-1β (40 ng/mL) + IL-1Ra (40 ng/mL) treatment group,and IL-1Ra (40 ng/mL) treatment group.The effect of IL-1β on SNAP-25 expression in primary hippocampal neuron was determined by Western blot and real-time PCR.The purity of hippocampal neurons were identified by NeuN immunofluorescence staining and the activity of neurons were detected by CCK-8 assay.All data were analyzed by SPSS version 22.0.The data were analyzed by student-t test and Dunnett-t test.The interaction effects were analyzed by factorial ANOVA.Differences were considered to be statistically significant if P＜ 0.05.Results Compared with the control group,the expressions of IL-1β and IL-1R1 were significantly increased in the hippocampus at 1,2 and 3 d after intraperitoneal injection of LPS (P＜0.05).The expression of SNAP-25 protein was decreased at 7,14,and 28 d after intraperitoneal injection of LPS (P＜0.05).The purity of primary neurons was about up to 92％.The activity of primary neurons was not relatively changed after treated with IL-1β at a dose less than 40 ng/mL.The level of SNAP-25 protein was obviously decreased in primary neurons at 24 h after IL-1β treatment (P＜0.05).IL-1Ra treatment might reverse the effect of IL-1β on primary neurons (P＜0.05).While,the expression of SNAP-25 mRNA was not statistically different in each group (P＞0.05).Conclusions IL-1β may possibly inhibit the expression level of SNAP-25 protein in the hippocampus in the septic rats through its receptor IL-1R1,which would contribute to cognitive dysfunction of septic neonatal rats in later life.