Cynandione A attenuates lipopolysaccharide-induced production of inflammatory mediators via MAPK inhibition and NF-κB inactivation in RAW264.7 macrophages and protects mice against endotoxin shock.

Cynanchum wilfordii has been traditionally used in eastern Asia for the treatment of various diseases such as gastrointestinal diseases and arteriosclerosis. Cynandione A (CA), an acetophenone, is one of major constituents from roots of C. wilfordii. In the present study, the anti-inflammatory activities of CA were investigated in lipopolysaccharide (LPS)-treated RAW264.7 macrophages and LPS-administered C57BL/6 N mice. CA significantly decreased LPS-induced production of nitric oxide and prostaglandin E2 in a dose-dependent manner, while CA up to 200 µM did not exhibit cytotoxic activity. Our data also showed that CA significantly attenuated expression of iNOS and COX-2 in LPS-stimulated macrophages. CA inhibited phosphorylation of IκB-α and MAP kinases such as ERK and p38. Furthermore, we demonstrated that CA inhibited translocation of NF-κB to the nucleus, transcription of the NF-κB minimal promoter and NF-κB DNA binding activity. Administration of CA significantly decreased the plasma levels of pro-inflammatory cytokines such as TNF-α, IL-6, and IL-1ß in LPS-injected mice and improved survival of septic mice with lethal endotoxemia. These results demonstrate that CA has effective inhibitory effects on production of inflammatory mediators via suppressing activation of NF-κB and MAPK signaling pathways, suggesting that CA may be used as a potential anti-inflammatory agent for the prevention and treatment of inflammatory diseases.

Protective effect of Disporum sessile D.Don extract against UVB-induced photoaging via suppressing MMP-1 expression and collagen degradation in human skin cells.

In the present study, we report that Disporum sessile D.Don herbal extract (DDE) possesses anti-skin photoaging effect through inhibition of MMP-1 mRNA and protein expression levels and increase collagen production in UVB-irradiated human dermal fibroblast cells (NHDF). To delineate the molecular mechanism by which DDE inhibited MMP-1 expression, immortal human keratinocytes cells (HaCaT) have been used. We have found that DDE inhibited UVB-induced MMP-1 mRNA and protein expression levels in HaCaT cells through inhibition of UVB-induced activation of NF-κB in HaCaT cells. Inhibitors of NF-κB (Bay11-7082), and mitogen-activated protein kinases such as extracellular regulated kinase (PD98059), c-Jun N-terminal kinase (SP600125), and p38 (SB203580) suppressed expression of MMP-1, and phosphorylation of these signaling molecules were attenuated by DDE. DDE also inhibited phosphorylation of IKKα and IκBα, and reduced nuclear translocation of NF-κB. Our results also demonstrated that DDE inhibited NF-κB driven expression of luciferase reporter gene and the DNA binding of NF-κB to its cognate binding site in UV-irradiated cells. Therefore, these results strongly suggest that DDE can be utilized as a potential agent for prevention and treatment of skin photoaging.

Inhibitory effects of a spinasterol glycoside on lipopolysaccharide-induced production of nitric oxide and proinflammatory cytokines via down-regulating MAP kinase pathways and NF-κB activation in RAW264.7 macrophage cells.

Extracts from the leaves of Stewartia koreana are known to exhibit strong anti-inflammatory activity. Investigation of bioactive compounds from S. koreana has led to the isolation of 3-O-ß-d-glucopyanosylspinasterol (spinasterol-Glc), a spinasterol glycoside. In the present study, we examined the effects of spinasterol-Glc on production of nitric oxide (NO) and proinflammatory cytokines in LPS-treated RAW264.7 macrophage cells and in mouse models. Our results showed that spinasterol-Glc inhibited the production of NO and proinflammatory cytokines such as TNF-α, IL-6 and IL-1ß in dose-dependent manners in LPS-treated RAW264.7 cells. Spinasterol-Glc inhibited the expression of iNOS and the proinflammatory cytokine genes. Spinasterol-Glc also inhibited phosphorylation of IκB-α and IKKα/ß as well as translocation of NF-κB to the nucleus. We demonstrated that spinasterol-Glc reduced transcription of the NF-κB minimal promoter and NF-κB DNA binding activity. Administration of the spinasterol-Glc significantly decreased the plasma levels of these inflammatory mediators including TNF-α, IL-6 and IL-1ß in LPS-injected mice and improved survival of septic mice with lethal endotoxemia. These results suggest that spinasterol-Glc has effective inhibitory effects on production of inflammatory mediators via inhibition of MAP kinases/NF-κB activities, and can be used as a potential anti-inflammatory agent for the prevention and treatment of inflammatory diseases.