Pretreatment with the compound asperuloside decreases acute lung injury via inhibiting MAPK and NF-κB signaling in a murine model.

Asperuloside, an iridoid glycoside found in Herba Paederiae, is a component from traditional Chinese herbal medicine. In this study, we aimed to investigate the protective effects and potential mechanisms of asperuloside action on inflammatory responses in lipopolysaccharide (LPS)-stimulated Raw 264.7 cells and an LPS-induced lung injury model. The pro-inflammatory cytokines and signaling pathways were measured by enzyme-linked immunosorbent assays (ELISA) and Western blotting to determine the effects of asperuloside. We found that asperuloside can significantly downregulate tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β, and IL-6 levels in vitro and in vivo, and treatment with asperuloside significantly reduced the lung wet-to-dry weight, histological alterations and myeloperoxidase activity in a murine model of LPS-induced acute lung injury (ALI). In addition, Western blot analysis that pretreatment with asperuloside remarkably blunted the phosphorylation of inhibitor of nuclear factor kappa-B (IκBα), extracellular signal-related kinases 1 and 2 (ERK1/2), c-Jun. N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38MAPK) in LPS-stimulated inflammation. These results indicate that asperuloside exerts its anti-inflammatory effect in correlation with inhibition of a pro-inflammatory mediator through suppressing nuclear factor kappa-B (NF-κB) nuclear translocation and MAPK phosphorylation in a dose-dependent manner.

Qiu J ，Chi G ，Wu Q ，Ren Y ，Chen C ，Feng H ... -  《-》

Protective effects of protocatechuic acid on acute lung injury induced by lipopolysaccharide in mice via p38MAPK and NF-κB signal pathways.

The study aims to investigate the effects of protocatechuic acid (PCA) separated from Chinese herbs, on acute lung injury (ALI) induced by lipopolysaccharide (LPS) in mice. The mouse model was induced by intraperitoneal injection of LPS at the dose of 5mg/kg body weight. Three doses of PCA (30, 15, 5 mg/kg) were administered to mice with intraperitoneal injection one hour prior to LPS exposure. Six hours later after LPS administration, the effect of PCA on ALI mice was assessed via histopathological examination by HE staining, inflammatory cytokine production by ELISA assay and RT-PCR, p38MAPK and NF-κB activation by Western blot analysis. We found that PCA administration significantly ameliorated lung histopathological changes and decreased protein concentration in the bronchoalveolar lavage fluid. Furthermore, the overproduction of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) was reduced by PCA. Additionally, PCA at the dose of 30 mg/kg could block the activation of p38MAPK and NF-κB signal pathways induced by LPS. In conclusion, our findings demonstrate that PCA possesses a protective effect on LPS-induced ALI in mice via suppression of p38MAPK and NF-κB signal pathways. Therefore, PCA may be useful in the therapy of lung inflammatory diseases, especially for ALI.

Zhang X ，Li C ，Li J ，Xu Y ，Guan S ，Zhao M ... -  《-》

Angelicin regulates LPS-induced inflammation via inhibiting MAPK/NF-κB pathways.

Angelicin is a furocoumarin found in Psoralea corylifolia L. fruit. The purpose of this study was to investigate the protective ability of angelicin against inflammation in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and LPS-induced in vivo acute lung injury model. The concentrations of tumor necrosis factor alpha (TNF-α) and interleukin (IL)-6 in the culture supernatants of RAW 264.7 cells were determined 24 h after LPS administration. ALI was induced by intratracheal instillation of LPS. Six hours after LPS inhalation, bronchoalveolar lavage fluid and lung tissue samples were obtained for enzyme-linked immunosorbent assay, histologic, and Western blotting analyses. The results showed that pretreatment with angelicin markedly downregulated TNF-α and IL-6 levels in vitro and in vivo, and significantly decreased the amount of inflammatory cells, lung wet-to-dry weight ratio, and myeloperoxidase activity in LPS-induced ALI mice. Furthermore, Western blotting analysis results demonstrated that angelicin blocked the phosphorylation of IκBα, NF-κBp65, p38 MAPK, and JNK in LPS-induced ALI. These results suggest that angelicin was potentially advantageous to prevent inflammatory diseases by inhibiting NF-κB and MAPK pathways. Our data indicated that angelicin might be a potential new agent for prevention of inflammatory reactions and diseases in the clinic.

Liu F ，Sun GQ ，Gao HY ，Li RS ，Soromou LW ，Chen N ，Deng YH ，Feng HH ... -  《-》

Tenuigenin ameliorates acute lung injury by inhibiting NF-κB and MAPK signalling pathways.

We aimed to explore the protective effect of tenuigenin (TNG) on lipopolysaccharide (LPS)-stimulated inflammatory responses in acute lung injury (ALI). Thus, we assessed the effects of TNG on the LPS-induced production of tumour necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β in the culture supernatants of RAW 264.7 cells. Male BALB/c mice were pretreated with commercial TNG (2, 4 and 8 mg/kg) and dexamethasone (Dex, 5mg/kg) for 1h prior to LPS (0.5 mg/kg) challenge. After 12h, airway inflammation was assessed. Our results showed that TNG dramatically decreased the production of TNF-α, IL-1β, and IL-6 in vitro and in vivo as well as the expression of COX-2 protein in vivo. Treatment with TNG not only significantly ameliorated LPS-stimulated histopathological changes but also reduced the myeloperoxidase (MPO) activity and the wet-to-dry weight ratio of the lungs. Furthermore, TNG blocked IκBα phosphorylation and degradation and inhibited p38/ERK phosphorylation in LPS-induced ALI. These findings suggest that TNG may have a protective effect on LPS-induced ALI and may be useful for the prevention and treatment of ALI in the clinical setting.

Lv H ，Zhu C ，Liao Y ，Gao Y ，Lu G ，Zhong W ，Zheng Y ，Chen W ，Ci X ... -  《-》

Sangxingtang inhibits the inflammation of LPS-induced acute lung injury in mice by down-regulating the MAPK/NF-κB pathway.

In the present study, we investigated anti-inflammatory effects of Sangxingtang (SXT) on acute lung injury using a lipopolysaccharide (LPS)-induced acute lung injury (ALI) mouse model. The cell counting in the bronchoalveolar lavage fluid (BALF) was performed. The degree of lung edema was evaluated by measuring the wet/dry weight (W/D) ratio. The superoxidase dismutase (SOD) and myeloperoxidase (MPO) activities were assayed by SOD and MPO kits, respectively. The levels of inflammatory mediators, including tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), were assayed by the enzyme-linked immunosorbent assay methods. Pathological changes of lung tissues were observed by Hematoxylin and eosin (HE) staining. The inflammatory signaling pathway-related proteins nuclear factor mitogen activated protein kinases (P38MAPK), extracellular regulated protein kinases (Erk), c-Jun N-terminal kinase (Jnk) and nuclear transcription factor (NF-κB) p65 expressions were measured by Western blotting. Our results showed that the treatment with the SXT markedly attenuated the inflammatory cell numbers in the BALF, decreased the levels of P-P38MAPK, P-Erk, P-Jnk and P-NF-κB p65 and the total protein levels in lungs, improved the SOD activity and inhibited the MPO activity. Histological studies demonstrated that SXT substantially reduced the LPS-induced neutrophils in lung tissues, compared with the untreated LPS group. In conclusion, our results indicated that SXT had protective effects on LPS-induced ALI in mice.

Zhang TZ ，Yang SH ，Yao JF ，Du J ，Yan TH ... -  《-》