The protective effects of Sauropus spatulifolius on acute lung injury induced by lipopolysaccharide

Da-Yuan-Yin decoction polyphenol fraction attenuates acute lung injury induced by lipopolysaccharide

CONTEXT

Da-Yuan-Yin is a Chinese traditional prescription.

OBJECTIVE

This study explores the therapeutic effects of the Da-Yuan-Yin decoction polyphenol fraction (DYY-4) on acute lung injury (ALI) in mice induced by lipopolysaccharide (LPS).

MATERIALS AND METHODS

The mice (n = 10) were orally administrated with DYY-4 (15, 30, and 60 mg/kg) or DXM (5 mg/kg), half an hour after LPS (2 mg/kg) instilled intratracheally. The protein content and the levels of inflammatory factors, the levels of complements, the mRNA expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), the level of myeloperoxidase (MPO) and superoxide dismutase (SOD), the expression of the IkB kinase (IKK) and nuclear factor-kappa B (NF-κB), the lung wet-to-dry weight (W/D) ratio and lung tissue were evaluated, 24 h after LPS challenge. Network pharmacology predicted potential targets.

RESULTS

DYY-4 (30, 60 mg/kg, p < 0.01, p < 0.01) decreased the lung W/D ratio, total protein concentration, the levels of C3, C3c and C5a, the levels of TNF-α, IL-6, and IL-1β, while increased the levels of IL-4 and IL-10. DYY-4 (60 mg/kg) decreased the levels of C5aR1, C5b-9 and COX-2 mRNA (p < 0.05), the levels of MPO and iNOS mRNA, the activation of the IKK/NF-κB pathway (p < 0.01), and increased the levels of IL-13 and SOD (p < 0.01). DYY-4 (60 mg/kg) relieved the lung tissue pathological changes and reduced the C3c deposition.

DISCUSSION AND CONCLUSIONS

Network pharmacology combined with animal experiments revealed the targets of DYY-4 alleviating ALI.

Diterpenoids from Sauropus spatulifolius Leaves with Antimicrobial Activities

As a plant used in both food and medicine, Sauropus spatulifolius is consumed widely as a natural herbal tea, food source, and Chinese medicine. Inspired by its extensive applications, we conducted a systematic phytochemical study of the leaves of S. spatulifolius. Thirteen new diterpenoids, sauspatulifols A-M (1-13), including four ent-cleistanthane-type diterpenoids (1-4), eight 15,16-di-nor-ent-cleistanthane-type diterpenoids (5-12), and one 17-nor-ent-pimarane-type diterpenoid (13) as well as one known diterpenoid, cleistanthol (14), were isolated. All of these diterpenoids feature a 2α,3α-dihydroxy unit within the A ring, and their structures were elucidated by spectroscopic data analysis, electronic circular dichroism calculations, and single-crystal X-ray diffraction analysis. Compound 14 displayed moderate inhibitory activity against Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, and Shigella flexneri with the same minimum inhibitory concentration value of 12 μg/mL as well as activity against vesicular stomatitis virus and influenza A virus.

Isolation and characterization of secondary metabolites from the leaves of Sauropus spatulifolius Beille and their potential biological assays

Eight new compounds (1-8), along with three known related compounds (9-11) were isolated from the leaves of Sauropus spatulifolius Beille. Their structures and configurations were elucidated by means of spectrometric and the modified Mosher's method. Among the new compounds, compounds 1 and 2 were identified as ethyl 3, 6-anhydro-2-deoxy-β-D-arabino-hexofuranoside (1) and ethyl 3, 6-anhydro-2-deoxy- hexofuranoside (2). Compounds 3-5 were the 2-acetylpyrrole derivatives and identified as 2-(2-acetyl-1H-pyrrol-1-yl)-4-hydroxybutyric acid (3), methyl 4-(2-acetyl-lH-pyrrol- 1-yl) butanoate (4) and 1, 4-bis (2-acetyl-1H-pyrrol-1-yl) butane (5), respectively. Compound 6 was elucidated as 7-megastigmane-3, 8, 9-triol. Compounds 7, 8 were identified as kaempferol-3-O-2-deoxy-β-D-glucoside (7) and kaempferol-3-O-β-D- glucopyranosyl-(1-6)-2-deoxy-β-D-glucoside (8). In addition, the cytotoxic activities of all the compounds were also evaluated, where compounds 3, 5, 7, 9\10 and 11 exhibited the magnificent inhibition activity on lung fibroblast differentiation induced by TGF-β1with low toxicity against the RLE-6TN cell.

The Anti-Inflammatory Effect of Trichilia martiana C. DC. in the Lipopolysaccharide-Stimulated Inflammatory Response in Macrophages and Airway Epithelial Cells and in LPS-Challenged Mice

A number of species of the genus Trichilia (Meliaceae) exhibit anti-inflammatory effects. However, the effect of Trichilia martiana C. DC. (TM) on lipopolysaccharide (LPS)-induced inflammation has not, to the best of our knowledge, yet been determined. Therefore, in the present study, the antiinflammatory effect of TM on LPS-stimulated RAW264.7 macrophages was evaluated. The ethanol extract of TM (TMEE) significantly inhibited LPS-induced nitric oxide (NO), prostaglandin 2 (PGE₂), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). TMEE also reduced the levels of inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β and IL-6. The upregulation of mitogen-activated protein kinases (MAPKs) and NF-κB activation was revealed to be downregulated following TMEE pretreatment. Furthermore, TMEE was indicated to lead to the nucleus translocation of nuclear factor erythroid-derived 2-related factor 2 (Nrf2) and the expression of heme oxygenase-1 (HO-1). In H292 airway epithelial cells, the pretreatment of TMEE significantly downregulated the production of LPS-stimulated IL-1β, and TMEE was indicated to increase the expression of HO-1. In animal models exhibiting LPS-induced acute lung injury (ALI), treatment with TMEE reduced the levels of macrophages influx and TNF-α production in the bronchoalveolar lavage fluid (BALF) of ALI mice. Additionally, TMEE significantly downregulated the activation of ERK, JNK and IκB, and upregulated the expression of HO-1 in the lungs of ALI mice. In conclusion, the results of the current study demonstrated that TMEE could exert a regulatory role in the prevention or treatment of the endotoxin-mediated inflammatory response.

miR-138-5p targets sirtuin1 to regulate acute lung injury by regulation of the NF-κB signaling pathway

Acute lung injury (ALI), a disease with a high mortality rate, is a noncardiogenic pulmonary inflammatory response and characterized by damage to the pulmonary system. In this study, we explored the mechanism of the occurrence and development of ALI. It was firstly found that miR-138-5p could inhibit the expression of sirtuin1 (SIRT1), and we further demonstrated that miR-138-5p targets directly SIRT1 through the luciferase assay, while the latter negatively regulated the expression of NF-κB. A549 cells were treated with lipopolysaccharide in vitro to simulate ALI cells and induce ALI in the model mice. The results showed that inhibiting the expression of miR-138-5p could effectively increase the viability of damaged cells, promote cell proliferation, reduce apoptosis, inhibit the inflammatory response, reduce oxidative stress, and then relieve ALI symptoms. Collectively, our results suggested that miR-138-5p can inhibit SIRT1 expression and indirectly activate the NF-κB signaling pathway, thus regulating the development of ALI.

Combining an in silico approach with an animal experiment to investigate the protective effect of troxerutin for treating acute lung injury

Background

Troxerutin (TRX), a naturally occurring flavonoid in various fruits, has been reported to exhibit numerous pharmacological and biological activities in vitro and in vivo. However, the molecular mechanisms underlying TRX as a treatment for disease are poorly understood.

Methods

Using pharmacophore mapping and inverse docking, a set of potential TRX target proteins that have been associated with multiple forms of diseases was obtained. Bioinformatic analyses were performed using the Enrichr and STRING servers to analyse the related biological processes and protein-protein networks. Furthermore, we investigated the potential protective effect of TRX against lipopolysaccharide-induced acute lung injury (ALI) using a mouse model. Morphological changes in the lungs were assessed using haematoxylin and eosin staining. Inflammatory cytokines, tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6 and IL-10 were investigated using ELISA. Activation of MAPK and NF-κB was detected using western blotting.

Results

Our network pharmacology analysis revealed the existence of multiple TRX-related chemical-target interactions and the related biological processes. We found that pretreatment with TRX protected against histological changes and obviously regulated the inflammatory cell counts and inflammatory cytokine levels in bronchoalveolar lavage fluid. Based on bioinformatic and western blot analyses, TRX may exert a protective effect against ALI by inhibiting MAPK and NF-κB signalling.

Conclusions

TRX can ameliorate pulmonary injury by inhibiting the MAPK and NF-κB signalling pathways and has a potential protective effect against ALI. This study may be helpful for understanding the mechanisms underlying TRX action and for discovering new drugs from plants for the treatment of ALI.

Electronic supplementary material

The online version of this article (10.1186/s12906-019-2515-7) contains supplementary material, which is available to authorized users.