Total flavonoids from sea buckthorn ameliorates lipopolysaccharide/cigarette smoke-induced airway inflammation.

The total flavonoids from sea buckthorn (TFSB) exhibit a potent anti-inflammatory activity; however, the effect of TFSB on respiratory inflammatory disease is not fully known. The present study evaluated the potential of TFSB to prevent airway inflammation and the underlying mechanism. The results showed that TFSB remarkably inhibited lipopolysaccharide/cigarette smoke extract (LPS/CSE)-induced expression of IL-1ß, IL-6, CXCL1, and MUC5AC at both mRNA and protein levels in HBE16 bronchial epithelial cells. TFSB also decreased the production of PGE2 through inhibition the expression of COX2 in LPS/CSE-stimulated HBE16 cells. Furthermore, bronchoalveolar fluid and histological analyses revealed that LPS/cigarette smoke exposure-induced elevated cell numbers of neutrophils and macrophages in bronchoalveolar fluid, inflammatory cell infiltration, and airway remodeling were remarkably attenuated by TFSB in mice. Immunohistochemical results also confirmed that TFSB decreased the expression of IL-1ß, IL-6, COX2, CXCL1, and MUC5AC in LPS/CS-exposed mice. Mechanistically, TFSB blocked LPS/CSE-induced activation of ERK, Akt, and PKCα. Molecular docking further confirmed that the main components in TFSB including quercetin and isorhamnetin showed potent binding affinities to MAPK1 and PIK3CG, two upstream kinases of ERK and Akt, respectively. In summary, TFSB exerts a potent protective effect against LPS/CS-induced airway inflammation through inhibition of ERK, PI3K/Akt, and PKCα pathways, suggesting that TFSB may be a novel therapeutic agent for respiratory diseases.

Ajudecumin A from Ajuga ovalifolia var. calantha exhibits anti-inflammatory activity in lipopolysaccharide-activated RAW264.7 murine macrophages and animal models of acute inflammation.

CONTEXT: Ajuga ovalifolia Bur. et Franch. var. calantha (Diels) C. Y. Wu et C. Chen (Labiatae), a traditional Chinese medicine, has been used to treat several inflammatory diseases. OBJECTIVE: To assess the anti-inflammatory activity of ajudecumin A isolated from Ajuga ovalifolia var. calantha, and its possible mechanisms. MATERIALS AND METHODS: Lipopolysaccharide (LPS, 0.5 µg/mL)-stimulated RAW264.7 macrophages were used to assess the anti-inflammatory activity of ajudecumin A (1-40 µM) in vitro. Nitric oxide levels were evaluated by Griess reagent. The mRNA levels of iNOS, COX-2, TNF-α, IL-1ß and IL-6 were determined using qRT-PCR. Phosphorylation of ERK, JNK, p38 MAPK and IκBα were detected by western Blot. To further assess the anti-inflammatory of ajudecumin A in vivo, mice were oral treated with ajudecumin A (10 mg/kg) or dexamethasone (0.25 mg/kg, positive control) for 5 days before administration of carrageenan or xylene. Paw and ear edema were then measured, respectively. RESULTS: Ajudecumin A (10-40 µM) decreased LPS-induced nitric oxide production with an IC50 value of 16.19 µM. Ajudecumin A (20 and 40 µM) also attenuated cell spreading and formation of pseudopodia-like structures, and decreased the mRNA levels of iNOS (55.23-67.04%, p < 0.001), COX-2 (57.58-70.25%, p < 0.001), TNF-α (53.75-58.94%, p < 0.01-0.001), IL-1ß (79.41-87.85%, p < 0.001) and IL-6 (54.26-80.52%, p < 0.01-0.001) in LPS-activated RAW264.7 cells. Furthermore, ajudecumin A suppressed LPS-induced phosphorylation of ERK, p38 MAPK, and IκBα, as well as IκBα degradation (p < 0.05-0.001). Finally, ajudecumin A (10 mg/kg) attenuated carrageenan- and xylene-induced inflammation in mice by about 28 and 24%, respectively. DISCUSSION AND CONCLUSIONS: Ajudecumin A exhibited a potent anti-inflammatory activity in vitro and in vivo through inhibition on NF-κB and ERK/p38 MAPK pathways, suggesting that ajudecumin A may be potentially developed as a lead compound in anti-inflammatory drug discovery.

A new xanthatin analogue 1ß-hydroxyl-5α-chloro-8-epi-xanthatin induces apoptosis through ROS-mediated ERK/p38 MAPK activation and JAK2/STAT3 inhibition in human hepatocellular carcinoma.

1ß-hydroxyl-5α-chloro-8-epi-xanthatin (XTT), a sesquiterpene lactone isolated from Xanthium sibiricum, possessed potent cytotoxicity on cancer cells in vitro. The objective of this study was to investigate the anti-tumor effect and underlying mechanisms of XTT on human hepatocellular carcinoma (HCC). Firstly, XTT inhibited the cell growth and induced apoptosis in human HCC cells, which was associated with the induction of Bax and cleaved-caspase-3, inhibition of Bcl-2 and survivin expression. Importantly, XTT induced the generation of reactive oxygen species (ROS) and malondialdehyde (MDA), and depletion of glutathione (GSH) in HCC cells through covalently modification of GSH. Furthermore, XTT caused obvious activation of extracellular regulated protein kinase (ERK) and p38 mitogen-activated protein kinase (p38 MAPK) and inactivation of Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) in HCC cells. ROS scavenger N-acetyl cysteine abrogated the effects of XTT on ERK/p38 MAPK activation and JAK2/STAT3 inhibition, and rescued HCC cells from XTT-induced apoptosis. Additionally, inhibitors of ERK/p38 MAPKs or activator of JAK2/STAT3 partially abolished XTT-mediated effect. In summary, XTT inhibited cell growth and induced apoptosis in HCC cells through ROS-mediated ERK/p38 MAPK activation and JAK2/STAT3 inhibition by GSH depletion. These findings also show the therapeutic potential of XTT in HCC.

Steroidal alkaloid solanine A from Solanum nigrum Linn. exhibits anti-inflammatory activity in lipopolysaccharide/interferon γ-activated murine macrophages and animal models of inflammation.

Solanine A is a novel steroidal alkaloid isolated from Solanum nigrum Linn., a medicinal and edible plant which is widely used for treating various inflammatory diseases. In this study, we found that solanine A markedly suppressed the production of nitric oxide (NO) and prostaglandin E2 (PGE2) in lipopolysaccharide/interferon-γ (LPS/IFNγ)-stimulated RAW264.7 cells, and attenuated xylene, carrageenan and agar-induced inflammation in mice. The mRNA levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX2), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and -1ß (IL-1ß), as well as C-X-C motif chemokine ligand-9 (CXCL9), were significantly decreased by solanine A. Furthermore, solanine A also suppressed LPS/IFNγ-induced protein expression of iNOS and COX2. Mechanistically, solanine A inhibited the nuclear translocation of nuclear factor-κB (NF-κB) through the prevention of NF-κB p65 and inhibitory κB-α (IκBα) phosphorylation and IκBα degradation, and it also suppressed activation of extracellular regulated protein kinases (ERK), signal transducers and activators of transcription-1 (STAT1) and serine/threonine protein kinase Akt in LPS/IFNγ-stimulated RAW264.7 macrophages and agar-induced granuloma model in mice. Taken together, solanine A exhibits a potent anti-inflammatory activity in LPS/IFNγ- activated macrophages and animal models of inflammation through inhibition of NF-κB, ERK1/2, Akt and STAT1 signaling pathways, suggesting that solanine A may be a valuable leading compound in the treatment of inflammatory diseases.