Sinomenine attenuates septic-associated lung injury through the Nrf2-Keap1 and autophagy.

OBJECTIVES: Our present study focused on assessing whether Sinomenine (SIN) could attenuate sepsis-induced acute lung injury (ALI). METHODS: The mice were conditioned with SIN 1 h before intraperitoneal injection of lipopolysaccharide (LPS). Lung wet/dry (W/D) ratio, inflammatory level in bronchoalveolar lavage fluid (BALF), malondialdehyde (MDA) levels, superoxide dismutase (SOD) activity and inflammatory cytokines production were detected. The expression of nuclear factor erythroid 2-like 2 (Nrf2) and autophagy-related proteins were detected by Western blot and immunohistochemical analyses. In addition, the RAW264.7 cells were treated with SIN 1 h before treatment with LPS. Inflammatory cytokines, iNOS and COX2 were detected. The expression of Nrf2 and autophagy-related proteins were explored by Western blot analysis. KEY FINDINGS: Experiments in vivo and in vitro discovered that LPS significantly increased the degree of injury, inflammatory cytokines production and oxidative stress. However, the increase was significantly inhibited by treatment of SIN. In addition, SIN was found to upregulate the expression of Nrf2 and autophagy-related proteins both in vivo and in vitro. CONCLUSIONS: Our data suggested that SIN could attenuate septic-associated ALI effectively, probably due to the inhibition of inflammation and oxidative stress through Nrf2 and autophagy pathways.

Sini decoction ameliorates sepsis-induced acute lung injury via regulating ACE2-Ang (1-7)-Mas axis and inhibiting the MAPK signaling pathway.

Sepsis, as life-threatening organ dysfunction caused by a dysregulated host response to infection, is characterized by the extensive release of cytokines and other mediators. Sini decoction (SND), a traditional Chinese prescription medicine, has been used clinically for the treatment of sepsis. But its explicit mechanism of action is still unclear. The present study aims to evaluate the potential protective effects of SND on sepsis-induced acute lung injury (ALI). After SND intervention, the lung tissues of each experimental group were collected. H&E sections were used to observe the pathological changes of lung tissue, and alveolar lavage fluid was collected to detect the infiltration of inflammatory cells. Level of inflammatory factors in lung tissue were analyzed by qRT-PCR. The change of Renin angiotensin system (RAS), as well as downstream MAPK/NF-κB signaling pathways were measured by Western blot. For in vitro experiments, human umbilical vein endothelial cells (HUVECs) were pretreated with lipopolysaccharide (LPS) and treated with SND. Subsequently, the expression levels of RAS and MAPK/NF-κB signaling pathways were measured by Western blot. In vivo, we found that SND significantly attenuated sepsis-induced pathological injury in the lung. SND also inhibited LPS-mediated inflammatory cell infiltration, the expression of pro-apoptotic proteins and the production of IL-6, IL-1ß, TNF-α and MCP-1. In vitro, experiments using a co-culture of HUVECs with SND showed that there was a decrease in pro-apoptotic protein and pro-inflammatory mediator. In this research, we also found that SND protective action could be attributed to the regulation of renin-angiotensin system (RAS). MAPKs and NF-κB pathways. To conclude, our study demonstrated that SND ameliorates sepsis-induced-ALI via regulating ACE2-Ang (1-7)-Mas axis and inhibiting the MAPK signaling pathway.

Sinomenine protects against E.coli-induced acute lung injury in mice through Nrf2-NF-κB pathway.

Acute lung injury (ALI) is a common disease characterized by pulmonary inflammation and oxidative stress. Sinomenine (SIN) is an alkaloid originally extracted from the Chinese medicinal plant Sinomenium acutum. It has been shown to have anti-inflammatory and anti-oxidative effect. However, it's unclear whether SIN can alleviate ALI. In this study, we assessed the effect of SIN on Escherichia coli (E.coli)-induced ALI mouse model. Mice were conditioned with SIN or placebo 1 h before intratracheally instilled with E.coli. Lung water content, malondialdehyde (MDA) content, superoxide dismutase (SOD) activity, Myeloperoxidase (MPO) levels and inflammatory cytokines production were measured. Immunohistochemistry and western blot were performed to measure target protein expression. E.coli induced histological changes indicating tissues damage and increased W/D ratio, MPO activity, MDA content, and inflammatory cytokines production in the Lung. Whereas in mice pretreated with SIN, these changes were absent. E.coli-induced NF-κB activation was also inhibited by SIN. In addition, SIN increased the expression of HO-1, NQO1 and Nrf2 in lung tissues. Our results suggest that SIN attenuates ALI through the inhibition of inflammation and oxidative stress.

Sini decoction alleviates E. coli induced acute lung injury in mice via equilibrating ACE-AngII-AT1R and ACE2-Ang-(1-7)-Mas axis.

AIMS: Acute respiratory distress syndrome (ARDS), one of the serious form of acute lung injury (ALI), is the primary cause of death in patients with ALI. Sini decoction (SND) is a widely used Traditional Chinese Medicine (TCM). However, the application of SND in ALI is rarely reported. Previous studies have found that renin-angiotensin-aldosterone system (RAAS) played vital and bidirectional roles in ALI. Therefore, the aim of the present study was to investigate protective effect of SND on ALI model induced by E. coli, as well as to further explore relations between RAAS and SND. MATERIALS AND METHODS: The ALI model was evaluated by morphological observations and biochemical assays. The expression levels of angiotensin converting enzyme (ACE), Angiotensin II type 1 receptor (AT1R) and angiotensin converting enzyme 2 (ACE2) were examined by Western blotting. The expression levels of angiotensinII (AngII) and angiotensin-(1-7) (Ang-(1-7)) were measured through ELISA. MasR, IL-6, IL-1ß and TNFα were all measured using qRT-PCR. KEY FINDINGS: SND significantly ameliorated E. coli-induced ALI, including reducing inflammatory factors in lung tissue and the activity of MPO in serum. Furthermore, SND could obviously decrease the expression of ACE, AngII and AT1R, which were induced by E. coli. On the other hand, SND could markedly activate ACE2-Ang-(1-7)-Mas pathway. SIGNIFICANCE: In this paper, we demonstrated that SND alleviates E. coli induced acute lung injury in mice via equilibrating ACE-AngII-AT1R and ACE2-Ang-(1-7)-Mas axis.