Effects of acteoside on lipopolysaccharide-induced inflammation in acute lung injury via regulation of NF-κB pathway in vivo and in vitro.

The purpose of the present study was to investigate the protective role of acteoside (AC) on lipopolysaccharide (LPS)-induced acute lung injury (ALI). BalB/c mice intraperitoneally received AC (30, and 60 mg/kg) or dexamethasone (2 mg/kg) 2h prior to or after intratracheal instillation of LPS. Treatment with AC significantly decreased lung wet-to-dry weight (W/D) ratio and lung myeloperoxidase (MPO) activity and ameliorated LPS-induced lung histopathological changes. In addition, AC increased super oxide dismutase (SOD) level and inhibited malondialdehyde (MDA) content, total cell and neutrophil infiltrations, and levels of proinflammatory cytokines including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) in bronchoalveolar lavage fluid (BALF) in LPS-stimulated mice. Furthermore, we demonstrated that AC inhibited the phosphorylation of IκBα, nuclear factor-κB (NF-κB) p65, inhibitor of nuclear factor kappa-B kinase-α (IKK-α) and inhibitor of nuclear factor kappa-B kinase-β (IKKβ) in LPS-induced inflammation in A549 cells. Our data suggested that LPS evoked the inflammatory response in lung epithelial cells A549. The experimental results indicated that the protective mechanism of AC might be attributed partly to the inhibition of proinflammatory cytokine production and NF-κB activation.

Jing W ，Chunhua M ，Shumin W 《-》

Protective effects of polydatin on lipopolysaccharide-induced acute lung injury through TLR4-MyD88-NF-κB pathway.

The purpose of this study was to investigate the protective effect of PD against lipopolysaccharide (LPS)-induced acute lung injury (ALI) and explore its potential mechanism. In vivo, PD and dexamethasone were intraperitoneally administered 1h before LPS stimulation. Then, mice were sacrificed at 6h post-LPS stimulation. Neutrophil number, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) in bronchoalveolar lavage fluid (BALF) were determined, as well as lung wet to dry ratio (W/D) and polymorphonuclear (MPO) activity. The protein expressions of Toll like receptor 4 (TLR4), myeloid differentiating factor 88 (MyD88), IL-1R-associated kinases 1 (IRAK1), IRAK4, inhibitor of nuclear factor kappa-B kinase (IKK)α, p-IKKα, IKKβ, p-IKKβ, inhibitor of NF-κB (IκBα), p-IκBα and NF-κB in lung tissues were assessed. Besides, we detected the IL-6, IL-1β, IL-8, TNF-α levels and TLR4, MyD88, NF-κB protein expressions in LPS-induced BEAS-2B cells. Consequently, PD significantly inhibited the levels of W/D, MPO, neutrophils number, TNF-α, IL-6, IL-1β and reversed TLR4-MyD88-NF-κB signaling pathway in lung tissues. In vitro assays, PD effectively negatively mediated the inflammatory cytokines and ameliorated the high expressions of TLR4, MyD88, NF-κB caused by LPS simulation in Human bronchial epithelial BEAS-2B cells. This study indicated that PD played a protective role in LPS-induced ALI and BEAS-2B cells. The results supported further study of PD as potential candidate for acute lung injury.

Jiang Q ，Yi M ，Guo Q ，Wang C ，Wang H ，Meng S ，Liu C ，Fu Y ，Ji H ，Chen T ... -  《-》

Kegan Liyan oral liquid ameliorates lipopolysaccharide-induced acute lung injury through inhibition of TLR4-mediated NF-κB signaling pathway and MMP-9 expression.

Kegan Liyan oral liquid (KGLY), a Chinese prescription modified from classic formulas Yin-Qiao-San (from TCM classic Wenbing Tiaobian) and Shen-Jie-San (first mentioned in Shanghan Wenyi Tiaobian), has been reported to exert heat-clearing and detoxifying effects and used extensively for the treatment of severe pulmonary diseases in clinics including influenza, cough and pneumonia. The purpose of this study was to investigate the protective effect of KGLY on lipopolysaccharide (LPS) induced acute lung injury (ALI) in mice and to illuminate the underlying mechanisms. Mice were orally administrated with KGLY (50, 100 and 150mg/kg) before intratracheal instillation of LPS. 24h post LPS challenge, lung tissues and the bronchoalveolar lavage fluid (BALF) were collected for lung wet/dry (W/D) weight ratio, histopathological examinations and biochemical analyses. The cell counts, protein concentration, interleukin-1β (IL-1β), interleukin-6 (IL-6), necrosis factor-α (TNF-α), macrophage inflammatory protein-2 (MIP-2) in BALF, superoxide dismutase (SOD), glutathione (GSH), myeloperoxidase (MPO) and malondialdehyde (MDA) levels were detected. Meanwhile, the activation of toll-like receptor 4 (TLR4), nuclear factor kappa B (NF-κB), as well as matrix metalloproteinases 9 (MMP-9) were determined by western blot assay. KGLY significantly prolonged mice survival time and ameliorated LPS-induced edema, thickening of alveolar septa and inflammatory cell infiltration in a dose-dependent manner. Additionally, KGLY markedly attenuated LPS-induced acute pulmonary inflammation via decreasing the expressions of cytokines and chemokines (IL-1β, IL-6, TNF-α, and MIP-2), enhanced the activities of anti-oxidative indicators (SOD and GSH), suppressed the levels of MPO and MDA, and down-regulated the expressions of TLR4, NF-κB and MMP9. The results suggested that the relieving effect of KGLY against LPS-induced ALI might be partially due to suppression of oxidative stress and inflammatory response, inhibition of TLR4-mediated NF-κB activation, and down-regulation of MMP9 expression, indicating it may be a potential therapeutic agent for ALI.

Zhang X ，Sun CY ，Zhang YB ，Guo HZ ，Feng XX ，Peng SZ ，Yuan J ，Zheng RB ，Chen WP ，Su ZR ，Huang XD ... -  《-》

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 ... -  《-》

Ulinastatin inhibits the inflammation of LPS-induced acute lung injury in mice via regulation of AMPK/NF-κB pathway.

Ulinastatin (ULI), a serine protease inhibitor, had been widely used as a drug for patients with acute inflammatory disorders. However, evidence regarding the anti-inflammatory effect of ulinastatin was still lacking. In this study, we investigated the protective mechanisms of ULI in LPS-induced acute lung injury (ALI). ALI was induced in mice by intratracheal instillation of LPS. The cells in the bronchoalveolar lavage fluid (BALF) were counted. The degree of animal lung edema was evaluated by measuring the wet/dry weight ratio and oxygenation index. The levels of inflammatory mediators, tumor necrosis factor-α, interleukin-1β, and interleukin-6, were assayed by enzyme-linked immunosorbent assay. Pathological changes of lung tissues were observed by HE staining. The levels of NF-κB p65, AMPK, p-AMPK and IκBα expression were detected by Western blotting. Then, selective AMPK inhibitor Compound C was used to test whether AMPK activation was critical in protection process of ULI against LPS-induced ALI. Ulinastatin pretreatment at doses of 15, 30 and 45mg/kg decreased LPS-induced evident lung histopathological changes, lung wet-to-dry weight ratio, and oxygenation index. Expression of IL-6, IL-1β, and TNF-α was suppressed by ULI at protein level in BALF. Additionally, the attenuation of inflammatory responses by ULI was closely associated with AMPK/NF-κB pathway and this effect was significantly inhibited by treatment with the AMPK inhibitor, Compound C. The results presented here indicated that ULI has a protective effect against LPS-induced ALI and this effect may be attributed partly to decreased production of proinflammatory cytokines through the regulation of AMPK/NF-κB signaling pathway.

Li W ，Qiu X ，Jiang H ，Zhi Y ，Fu J ，Liu J ... -  《-》