4-O-Methylhonokiol Protects HaCaT Cells from TGF-β1-Induced Cell Cycle Arrest by Regulating Canonical and Non-Canonical Pathways of TGF-β Signaling

4-O-methylhonokiol, a neolignan compound from Magnolia Officinalis, has been reported to have various biological activities including hair growth promoting effect. However, although transforming growth factor-β (TGF-β) signal pathway has an essential role in the regression induction of hair growth, the effect of 4-O-methylhonokiol on the TGF-β signal pathway has not yet been elucidated. We thus examined the effect of 4-O-methylhonokiol on TGF-β-induced canonical and noncanonical pathways in HaCaT human keratinocytes. When HaCaT cells were pretreated with 4-O-methylhonokiol, TGF-β1-induced G1/G0 phase arrest and TGF-β1-induced p21 expression were decreased. Moreover, 4-O-methylhonokiol inhibited nuclear translocation of Smad2/3, Smad4 and Sp1 in TGF-β1-induced canonical pathway. We observed that ERK phosphorylation by TGF-β1 was significantly attenuated by treatment with 4-O-methylhonokiol. 4-O-methylhonokiol inhibited TGF-β1-induced reactive oxygen species (ROS) production and reduced the increase of NADPH oxidase 4 (NOX4) mRNA level in TGF-β1-induced noncanonical pathway. These results indicate that 4-O-methylhonokiol could inhibit TGF-β1-induced cell cycle arrest through inhibition of canonical and noncanonical pathways in human keratinocyte HaCaT cell and that 4-O-methylhonokiol might have protective action on TGF-β1-induced cell cycle arrest.

Anti-inflammatory and Anti-oxidant Effects of Sophora flavescens Root Extraction in Lipopolysaccharide-activated Raw 264.7 Cells / 대한의진균학회지

BACKGROUND: The macrophages activated by lipopolisaccharide produce numerous molecules and proteins, such as tumor necrotic factor-alpha (TNF-alpha), interleukin-6 (IL-6), IL-1beta, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and free radicals, associated with inflammation. The response was occurred by intracellular cascaded, NF-kappaB pathway. So, the regulation of this pathway is very important in control of inflammation. OBJECTIVE: In this study, the anti-inflammatory and anti-oxidant effects of Sophora flavescens that is used empirically in oriental medicine and folk remedy were evaluated and the mechanism of the effects was studied. METHODS: By using the root extracts of Sophora flavescens, we performed experiment in LPS and interferon-gamma (IFN-gamma)-activated Raw 264.7 cells. We measured the production of NO, PGE2 and expression of iNOS and COX-2 in activated Raw 264.7 cells with Sophora flavescens root extract. Also, we tested anti-oxidant effect of Sophora flavescens root extracts by ELISA kit in activated Raw 264.7 cells, and the free radical scavenging effect of material itself by DPPH assay. RESULTS: The Sophora flavescens root extracts decreased the production of NO (p<0.001) and PGE2 (p<0.01) in Raw 264.7 cells activated by LPS and IFN-gamma. The expression of proteins, iNOS and COX-2, suppressed along with the elevated concentration of Sophora flavescens root extracts. The result of DPPH assay was that the test material itself had scavenging effect for free radical (p<0.001). And the antioxidant activity in activated Raw 264.7 cells was increased with the level of the Sophora flavescens root extracts (p<0.05). CONCLUSION: The Sophora flavescens root extracts suppressed the production of NO and PGE2 through the decreased expression of iNOS and COX-2. And the Sophora flavescens root extracts had the scavenging effect about free radicals itself and increased the antioxidant activity in activated macrophages.