The effects of Rheu compositus on alveolar macrophages NF-κB activity and inflammatory cytokine expres-sion in rats with ARDS / 中华急诊医学杂志

Objective Tostudy the effects ofRheu compositus (Dachengqi Decoction, DD) on the NF-κBactivity of alveolar macrophages in ARDS rats and its inflammatory cytokine expression, and hence to explore the molecular mechanism of the anti-inflammatory effects of DD. Method The 65 male Wistar rats were randomly di-vided into the control group (n = 12), the ARDS model group (n = 21), the DD treatment group (n = 16) and the dexamethasone treatment group (n = 16). The rots of model group received 1 mg/(kg·0.5 mL) LPS injected intra-poritoneally and LPS in dose of 5 mg/(kg·0. 5 mL) was administrated by slow dropping endotracbeally 16 hours later. Modeling was successfully established 6 hours later evidenced by arterial gas analysis. The rats of con-trol group received 0.5 mL normal saline injected intravenously through tail vein instead of LPS. Three days after establishment of modeling, DD was given to rats of DD treatment group by intragastric instillation for 3 days in dose of 2.31 g/(kg·d),in which the weight of drug was calculated on the basis of dried herbal medicine. In dexam-ethasone treatment group, rats had intra-peritoneal injection of 2 mg/kg dexamethasone for 3 days after modeling was established. Seventy-two hours later, the arterial blood gas analysis and pathological study were carried out, in rats of all groups, and the findings were graded. The levels of TNF-α, IL-1 and IL-10 both in the plasma and in the brenchoalveolar lavage fluid were determined by using the enzyme linked immunosorbent assay (ELISA). Besides the nucleopretein concentration of pulmonary alveolar macrophage (PAM) was maeasuredwith the BAC method, and the NF-κB activity was determined with the Western Blotting, and with the evaluation of the DD' s effect on the transcription activity of PAM inflammatory cytokines. All the experimental data were processed by the SPSS 13.0 for statistical analysis. The analysis of variance was used for the comparison between groups, and P < 0. 05 showed the statistical significance of the difference. Results DD didn' t significantly reduce the TNF-α level [(510.97±76.20) pg/mL,(476.16±98.03) pg/mL, P >0.05], but significantly deceased the plasma IL-1 level [(381.99±34.30) pg/mL, (300.69 ± 50.99) pg/mL, P <0.05]. At the same time, there was no signif-icant changes in the plasma IL-10 level [(345.96 ± 67.72) pg/mL, (345.30 ± 78.52) pg/mL, P > 0.05]. Whereas TNF-α level in BALF was significantly decreased [(130.94 ± 33.51) pg/mL, (106.59 ± 26.64) pg/ mL, P < 0. 05, so was the IL-1 level in BALF (82.5 ± 25.36) pg/mL, (63.89 ± 22.96) pg/mL, P < 0. 05], but IL-10 level in the BALF was significantly increased[(77.09 ± 26.05) pg/mL, (148.05 ± 53.50) pg/mL, P <0.01]. DD significantly reduced the nueleoprotein level of PAM[(5.35 ± 2.44) μg/μL, (3.54 ± 2.01) μg/ μL, P < 0.05]and significantly inhibited the NF-κB activity [electrophoretic band optical density × area/consult mtio:(1.45±0.71),(1.11±0.28), P <0.05]aswell. Conclusions DD regulated systemic pro-inflammato-ry media/anti-inflammatory media balance in rats with ARDS by mainly reducing the level of IL-1. The regulatory effects of DD on the local lung injury not only inhibit the producing of TNF-α and IL-1 level,but also increase the IL-10 level to reestablish the local pro-inflammatory factors/anti-inflammatory factors balance so as to inhibit the lo-cal excessive irranune response. DD inhibits the NF-κB activity in the PAM of ARDS rats so as to restrain the pro-duction of pro-inflammatory cytokines (TNF-α and IL-1). This kind of multi-target bidirectional regulation plays an active role in regulating the immune balance and protecting the target organ from the excessive injury.

Superoxide Dismutase Gene Expression Induced by Lipopolysaccharide in Alveolar Macrophage of Rat / 결핵

BACKGROUND: In the pathogenesis of acute lung injury induced by lipopolysaccharide(LPS), oxygen radiclls are known to be involved in one part. Superoxide dismutase(SOD) protects oxygen radical-induced tissue damage by dismutating superoxide to hydrogen peroxide. In eukaryotic cells, two forms of SOD exist intracellularly as a cytosolic, dimeric copper/zinc-containing SOD (CuZnSOD) and a mitochondrial, tetrameric manganese-containing SOD(MnSOD). But there has been little information about SOD gene expression and its regulation in pulmonary alveolar macrophages(PAMs). The objective of this study is to evaluate the SOD gene expression induced by LPS and its regulation in PAMs of rat. METHOD: In Sprague-Dawley rats, PAMs obtained by broncholaveolar lavage were purified by adherence to plastic plate. To study the effect of LPS on the SOD gene expression of PAMs, they were stimulated with different doses of LPS(0.01microg/ml ~ 10microg/ml) and for different intervals(0, 2, 4, 8, 24hrs). Also for evaluating the level of SOD gene regulation actinomycin D(AD) or cyclo- heximide(CHX) were added respectively. To assess whether LPS altered SOD mRNA stability, the rate of mRNA decay was determined in control group and LPS-treated group. Total cellular RNA extraction by guanidinium thiocyanate/phenol/chloroform method and Northern blot analysis by using a 32P-labelled rat MnSOD and CuZnSOD cDNAs were performed. RESULTS: The expression of mRNA in MnSOD increased dose-dependently, but not in CuZnSOD. MnSOD mRNA expression peaked at 8 hours after LPS treatment. Upregulation of MnSOD mRNA expression induced by LPS was suppressed by adding AD or CHX respectively. MnSOD mRNA stability was not altered by LPS. CONCLUSION: These findings show that PAMs of rat could be an important source of SOD in response to LPS, and suggest that their MnSOD mRNA expression may be regulated transcriptionally and require de novo protein synthesis without affecting mRNA stability.

Role of Pulmonary Alveolar Macrophage in Lung Injury after Burn—Blast Combined Injury / 中华创伤杂志

In order to clarify the relationship between PAMs and post—trauma lung injury, the H_2O_2 produced by PAMs and catalase activity of bronchoalveolar lavage fluid (BALF) and lung homogenate were measured at hours 6、12、24、48 and 72 after burn、blast injury and burn—blast combined injury in 128 rats, respectively. After trauma, H_2O_2 produced by PAMs was increased compared with PAMs from control lungs, especially in the combined injury groups. The catalase activity of BALF and lung homogenate decreased. The catalase activity in combined injured lungs was the lowest. The results indicated 1. the activation of PAMs might play a role in post—trauma lung injury: 2. the damage of pulmonary antioxidant system after trauma may enhanced the lung injury; 3. the state of PAMs activation and the damage of pulmonary antioxidant system were related to the severity of trauma.