The flavonoid hydroxygenkwanin reduces inflammation and neointimal formation.

BACKGROUND AND OBJECTIVES: Abnormal vascular smooth muscle cell (VSMC) proliferation and migration play crucial roles in neointimal hyperplasia and restenosis progression in response to stimulation with various inflammatory cytokines, such as platelet-derived growth factor-BB (PDGF-BB) and tumour necrosis factor-α (TNF-α). Hydroxygenkwanin (HGK) exerts remarkable anti-inflammatory, antitumour, antiproliferative and antimigratory effects. The aim of the study was to elucidate the therapeutic effect and regulatory mechanism of HGK on neointimal hyperplasia. METHODS: Western blot analysis, cell cycle analysis, and MTT, BrdU incorporation, wound healing and adhesion assays were performed in vitro to determine the therapeutic effects of HGK in PDGF-BB- or TNF-α-treated VSMCs. Docking analysis and cellular thermal shift assay were also performed to elucidate the mechanism underlying the regulatory effect of HGK. Histological and immunohistochemical staining of denuded femoral arteries was conducted to elucidate the therapeutic effect of HGK in vivo. RESULTS AND CONCLUSIONS: HGK inhibited the abnormal proliferation, migration, and inflammation of PDGF-BB- or TNF-α-treated VSMCs through regulation of the PDK1/AKT/mTOR pathway. In addition, HGK promoted circulating endothelial progenitor cell (EPC) chemotaxis. In an in vivo assay, HGK dramatically enhanced re-endothelization and reduced neointimal hyperplasia after femoral artery denudation with a guide wire in mice. These results suggest that HGK can serve as a therapeutic target drug or a functional food supplement for the treatment of restenosis.

Increasing DNA damage sensitivity through corylin-mediated inhibition of homologous recombination.

BACKGROUND: DNA repair allows the survival of cancer cells. Therefore, the development of DNA repair inhibitors is a critical need for sensitizing cancers to chemoradiation. Sae2CtIP has specific functions in initiating DNA end resection, as well as coordinating cell cycle checkpoints, and it also greatly interacts with the DDR at different levels. RESULTS: In this study, we demonstrated that corylin, a potential sensitizer, causes deficiencies in DNA repair and DNA damage checkpoints in yeast cells. More specifically, corylin increases DNA damage sensitivity through the Sae2-dependent pathway and impairs the activation of Mec1-Ddc2, Rad53-p and γ-H2A. In breast cancer cells, corylin increases apoptosis and reduces proliferation following Dox treatment by inhibiting CtIP. Xenograft assays showed that treatment with corylin combined with Dox significantly reduced tumor growth in vivo. CONCLUSIONS: Our findings herein delineate the mechanisms of action of corylin in regulating DNA repair and indicate that corylin has potential long-term clinical utility as a DDR inhibitor.

Isoxanthohumol reduces neointimal hyperplasia through the apelin/AKT pathway.

The abnormal proliferation, migration, and inflammation of vascular smooth muscle cells (VSMCs) play crucial roles in the development of neointimal hyperplasia and restenosis. Exposure to inflammatory cytokines such as platelet-derived growth factor (PDGF)-BB and tumour necrosis factor-alpha (TNF-α) induces the transformation of contractile VSMCs into abnormal synthetic VSMCs. Isoxanthohumol (IXN) has significant anti-inflammatory, antiproliferative, and antimigratory effects. This study aimed to explore the therapeutic impact and regulatory mechanism of IXN in treating neointimal hyperplasia. The present findings indicate that IXN effectively hinders the abnormal proliferation, migration, and inflammation of VSMCs triggered by PDGF or TNF-α. This inhibition is primarily achieved through the modulation of the apelin/AKT or AKT pathway, respectively. In an in vivo model, IXN effectively reduced neointimal hyperplasia in denuded femoral arteries. These results suggest that IXN holds promise as a potential and innovative therapeutic candidate for the treatment of restenosis.

Corylin Attenuates CCl4-Induced Liver Fibrosis in Mice by Regulating the GAS6/AXL Signaling Pathway in Hepatic Stellate Cells.

Liver fibrosis is reversible when treated in its early stages and when liver inflammatory factors are inhibited. Limited studies have investigated the therapeutic effects of corylin, a flavonoid extracted from Psoralea corylifolia L. (Fabaceae), on liver fibrosis. Therefore, we evaluated the anti-inflammatory activity of corylin and investigated its efficacy and mechanism of action in ameliorating liver fibrosis. Corylin significantly inhibited inflammatory responses by inhibiting the activation of mitogen-activated protein kinase signaling pathways and the expression of interleukin (IL)-1ß, IL-6, and tumor necrosis factor-alpha in human THP-1 and mouse RAW264.7 macrophages. Furthermore, corylin inhibited the expression of growth arrest-specific gene 6 in human hepatic stellate cells (HSCs) and the activation of the downstream phosphoinositide 3-kinase/protein kinase B pathway. This inhibited the activation of HSCs and the expression of extracellular matrix proteins, including α-smooth muscle actin and type I collagen. Additionally, corylin induced caspase 9 and caspase 3 activation, which promoted apoptosis in HSCs. Moreover, in vivo experiments confirmed the regulatory effects of corylin on these proteins, and corylin alleviated the symptoms of carbon tetrachloride-induced liver fibrosis in mice. These findings revealed that corylin has anti-inflammatory activity and inhibits HSC activation; thus, it presents as a potential adjuvant in the treatment of liver fibrosis.

Larixol inhibits fMLP-induced superoxide anion production and chemotaxis by targeting the ßγ subunit of Gi-protein of fMLP receptor in human neutrophils.

The over-activated neutrophils through G-protein-coupled receptors (GPCRs) caused inflammation or tissue damage. Therefore, GPCRs or their downstream molecules are major targets for inhibiting uncontrolled neutrophil activation. Our studies investigate the action and underlying mechanism of larixol, a diterpene extract from the root of euphorbia formosana, on fMLP-induced neutrophil respiratory burst, chemotaxis, and granular release. The immunoprecipitation assay was performed to investigate whether larixol inhibits fMLP-induced respiratory burst by interfering with the interaction of fMLP receptor Gi-protein ßγ subunits with its downstream molecules. Briefly, larixol inhibited fMLP (0.1 µM)-induced superoxide anion production (IC50:1.98 ± 0.14 µM), the release of cathepsin G (IC50:2.76 ± 0.15 µM) and chemotaxis in a concentration-dependent manner; however, larixol did not inhibit these functions induced by PMA (100 nM). Larixol inhibited fMLP-induced Src kinase phosphorylation. Therefore, larixol attenuated the downstream signaling of Src kinases, ERK1/2, p38, and AKT phosphorylation. Moreover, larixol inhibited fMLP-induced intracellular calcium mobilization, PKC phosphorylation, and p47phox translocation from the cytosol to the plasma membrane. Larixol inhibited the interaction of the ßγ subunits of Gi-protein of fMLP receptor with Src kinase or with PLCß by the immunoprecipitation and duolink assay. Furthermore, larixol did not antagonize the formyl peptide receptors. Larixol did not increase cyclic nucleotide levels in neutrophils. These results suggest that larixol modulated fMLP-induced neutrophils superoxide anion production, chemotaxis, and granular releases by interrupting the interaction of the ßγ subunits of Gi-protein with downstream signaling of the fMLP receptor.

Psorachromene induces apoptosis and suppresses tumor growth in NSCLC cells harboring EGFR L858R/T790M/C797S.

The extracts from Psoralea corylifolia Linn. (P. corylifolia) seeds have been shown to display antitumor activity. To date, the prospects of this plant and its active compounds in the treatment of non-small-cell lung cancer (NSCLC) have not been thoroughly studied. In this study, we identified a novel psorachromene compound that displays selective cytotoxic effects on all NSCLC cells tested, including NSCLC cells harboring epidermal growth factor receptor (EGFR) activation mutants (H1975L858R/T790M and H1975-MS35L858R/T790M/C797S ). Psorachromene induces G1 arrest in NSCLC cells harboring wild-type EGFR but induces apoptosis in NSCLC cells harboring activating EGFR mutations. Psorachromene inhibits activated EGFR signaling and kinase activity and suppresses tumor growth of implanted H1975-MS35L858R/T790M/C797S cells in nude mice. Molecular docking analysis revealed that psorachromene could form stronger bonds with mutant EGFR than wild-type EGFR, which might account for the greater cytotoxic effects observed in NSCLC cells harboring activating EGFR mutations (H1975 and H1975-MS35) than wild-type EGFR (A549). In conclusion, it is suggested that psorachromene is an attractive agent to be further explored for its use in the treatment of NSCLC patients harboring EGFR L858R/T790M/C797S.

Euphormins A and B, New Pyranocoumarin Derivatives from Euphorbia formosana Hayata, and Their Anti-Inflammatory Activity.

Euphormin-A (1) and euphormin-B (2), two new pyranocoumarin derivatives, and forty known compounds (3-42) were isolated from Euphorbia formosana Hayata (Euphorbiaceae). The chemical structures of all compounds were established based on spectroscopic analyses. Several isolates were evaluated for their anti-inflammatory activity. Compounds 1, 2, 10, 18, 25, and 33 significantly inhibited against superoxide anion generation and elastase release by human neutrophils in response to formyl-L-methionyl-L-leucyl-L-phenylalanine/cytochalasin B (fMLP/CB). Furthermore, compounds 25 and 33 displayed the most potent effects with IC50 values of 0.68 ± 0.18 and 1.39 ± 0.12 µM, respectively, against superoxide anion generation when compared with the positive control (2.01 ± 0.06 µM).

Modulation of Gut Microbiota Combined with Upregulation of Intestinal Tight Junction Explains Anti-Inflammatory Effect of Corylin on Colitis-Associated Cancer in Mice.

Inflammatory bowel disease (IBD) involves chronic inflammation, loss of epithelial integrity, and gastrointestinal microbiota dysbiosis, resulting in the development of a colon cancer known as colitis-associated colorectal cancer (CAC). In this study, we evaluated the effects of corylin in a mouse model of dextran sodium sulfate (DSS)-induced colitis. The results showed corylin could improved the survival rate and colon length, maintained body weight, and ameliorated the inflammatory response in the colon. Then, we further identified the possible antitumor effects after 30-day treatment of corylin on an azoxymethane (AOM)/DSS-induced CAC mouse model. Biomarkers associated with inflammation, the colon tissue barrier, macrophage polarization (CD11c, CCR7, CD163, and CD206), and microbiota dysbiosis were monitored in the AOM/DSS group versus corylin groups. Corylin downregulated pro-inflammatory cytokines (TNF-α, IFN-γ, IL-1ß, and IL-6) mRNA expression and inflammatory signaling-associated markers (TLR4, MyD88, AP-1, CD11b, and F4/80). In addition, a colon barrier experiment revealed that epithelial cell proliferation of the mucus layer (Lgr5, Cyclin D1, and Olfm4) was downregulated and tight junction proteins (claudin-1 and ZO-1) were upregulated. Furthermore, the Firmicutes/Bacteroidetes ratio changed with corylin intervention, and the microbial diversity and community richness of the AOM/DSS mice were improved by corylin. The comparative analysis of gut microbiota revealed that Bacteroidetes, Patescibacteria, Candidatus Saccharimonas, Erysipelatoclostridium, and Enterorhabdus were significantly increased but Firmicutes, Turicibacter, Romboutsia, and Blautia decreased after corylin treatment. Altogether, corylin administration showed cancer-ameliorating effects by reducing the risk of colitis-associated colon cancer via regulation of inflammation, carcinogenesis, and compositional change of gut microbiota. Therefore, corylin could be a novel, potential health-protective, natural agent against CAC.

The flavonoid corylin exhibits lifespan extension properties in mouse.

In the long history of traditional Chinese medicine, single herbs and complex formulas have been suggested to increase lifespan. However, the identification of single molecules responsible for lifespan extension has been challenging. Here, we collected a list of traditional Chinese medicines with potential longevity properties from pharmacopeias. By utilizing the mother enrichment program, we systematically screened these traditional Chinese medicines and identified a single herb, Psoralea corylifolia, that increases lifespan in Saccharomyces cerevisiae. Next, twenty-two pure compounds were isolated from Psoralea corylifolia. One of the compounds, corylin, was found to extend the replicative lifespan in yeast by targeting the Gtr1 protein. In human umbilical vein endothelial cells, RNA sequencing data showed that corylin ameliorates cellular senescence. We also examined an in vivo mammalian model, and found that corylin extends lifespan in mice fed a high-fat diet. Taken together, these findings suggest that corylin may promote longevity.

Propolin G-Suppressed Epithelial-to-Mesenchymal Transition in Triple-Negative Breast Cancer Cells via Glycogen Synthase Kinase 3ß-Mediated Snail and HDAC6-Regulated Vimentin Degradation.

Triple-negative breast cancer (TNBC) is a highly aggressive breast cancer with a poor prognosis. The incidence and mortality rate of TNBC are frequently found in younger women. Due to the absence of a good therapeutic strategy, effective remedies for inhibiting TNBC have been developed for improving the cure rate. Epithelial-to-mesenchymal transition (EMT) is a critical mechanism to regulate cancer cell motility and invasion. Furthermore, ectopic expression of EMT molecules correlates with the metastasis and poor prognosis of TNBC. Targeting EMT might be a strategy for the therapy and prevention of TNBC. Propolin G, an active c-prenylflavanone in Taiwanese propolis, has been shown to possess anti-cancer activity in many cancers. However, the anti-metastasis activity of propolin G on TNBC is still unclear. The present study showed that the migration and invasion activities of TNBC cells was suppressed by propolin G. Down-regulated expression of Snail and vimentin and up-regulated expression of E-cadherin were dose- and time-dependently observed in propolin G-treated MDA-MB-231 cells. Propolin G inhibited Snail and vimentin expressions via the signaling pathways associated with post-translational modification. The activation of glycogen synthase kinase 3ß (GSK-3ß) by propolin G resulted in increasing GSK-3ß interaction with Snail. Consequently, the nuclear localization and stability of Snail was disrupted resulting in promoting the degradation. Propolin G-inhibited Snail expression and the activities of migration and invasion were reversed by GSK-3ß inhibitor pretreatment. Meanwhile, the outcomes also revealed that histone deacetylase 6 (HDAC6) activity was dose-dependently suppressed by propolin G. Correspondently, the amounts of acetyl-α-tubulin, a down-stream substrate of HDAC6, were increased. Dissociation of HDAC6/Hsp90 with vimentin leading to increased vimentin acetylation and degradation was perceived in the cells with the addition of propolin G. Moreover, up-regulated expression of acetyl-α-tubulin by propolin G was attenuated by HDAC6 overexpression. On the contrary, down-regulated expression of vimentin, cell migration and invasion by propolin G were overturned by HDAC6 overexpression. Conclusively, restraint cell migration and invasion of TNBC by propolin G were activated by the expression of GSK-3ß-suppressed Snail and the interruption of HDAC6-mediated vimentin protein stability. Aiming at EMT, propolin G might be a potential candidate for TNBC therapy.

Phytochemical­rich herbal formula ATG­125 protects against sucrose­induced gastrocnemius muscle atrophy by rescuing Akt signaling and improving mitochondrial dysfunction in young adult mice.

The antioxidant capability of herbal remedies has attracted widespread attention, but their molecular mechanisms in a muscle atrophy model have not been explored. The aim of the present study was to compare the bioactivity of sucrose challenged mice following treatment with ATG­125. Here, through a combination of transcriptomic and biomedical analysis, herbal formula ATG­125, a phytochemical­rich formula, was identified as a protective factor against muscle atrophy in sucrose challenged mice. Gene ontology (GO) identified differentially expressed genes that were primarily enriched in the 'negative regulation of proteolysis', 'cellular amino acid metabolic process', 'lipoprotein particle' and 'cell cycle', all of which were associated with the ATG­125­mediated prevention of muscle atrophy, particularly with regard to mitochondrial biogenesis. In skeletal muscle, a set of mitochondrial­related genes, including angiopoietin­like 4, nicotinamide riboside kinase 2 (Nmrk2), pyruvate dehydrogenase lipoamide kinase isozyme 4, Asc­type amino acid transporter 1 and mitochondrial uncoupling protein 3 (Ucp3) were markedly upregulated following ATG­125 intervention. An increase in Nmrk2 and Ucp3 expression were noted after ATG­125 treatment, in parallel with upregulation of the 'nicotinate and nicotinamide metabolism' pathway, as determined using the Kyoto Encyclopedia of Genes and Genomes (KEGG). Furthermore, KEGG pathway analysis revealed the downregulation of 'complement and coagulation cascades', 'cholesterol metabolism', 'biosynthesis of amino acids' and 'PPAR signaling pathway', which were associated with the downregulation of serine (or cysteine) peptidase inhibitor clade A member (Serpina)3, Serpina1b, Serpina1d, Serpina1e, apolipoprotein (Apo)a1 and Apoa2, all of which were cardiovascular and diabetes­associated risk factors and were regulated by ATG­125. In addition, ATG­125 treatment resulted in downregulated mRNA expression levels of ATPase sarcoplasmic/endoplasmic reticulum Ca2+ transporting 2, troponin­I1, troponin­C1 and troponin­T1 in young adult gastrocnemius muscle compared with the sucrose group. Nuclear factor­κB­hypoxia inducible factor­1α­TGFß receptor type­II­vascular endothelial growth factor staining indicated that ATG­125 decreased sucrose­induced chronic inflammation. ATG­125 was sufficient to prevent muscle atrophy, and this protective effect may be mediated through upregulation of AKT phosphorylation, upregulating the insulin growth factor­1R­insulin receptor substrate­PI3K­AKT pathway, which in turn resulted in a forkhead box O­dependent decrease in protein degradation pathways, including regulation of atrogin1 and E3 ubiquitin­protein ligase TRIM63. Peroxisome­proliferator activated receptor γ coactivator 1α (PGC1α) was decreased in young adult mice challenged with sucrose. ATG­125 treatment significantly increased PGC1α and significantly increased UCP­1,2,3 expression levels, which suggested ATG­125 poised the mitochondria for uncoupling of respiration. This effect is consistent with the increased SIRT1 levels and may explain an increase in mitochondria biogenesis. Taken together, the present study showed that ATG­125, as an integrator of protein synthesis and degradative pathways, prevented muscle wasting.

Astragalus mongholicus Bunge Water Extract Exhibits Anti-inflammatory Effects in Human Neutrophils and Alleviates Imiquimod-Induced Psoriasis-Like Skin Inflammation in Mice.

Neutrophils are the primary immune cells in innate immunity, which are related to various inflammatory diseases. Astragalus mongholicus Bunge is a Chinese medicinal herb used to treat various oxidative stress-related inflammatory diseases. However, there are limited studies that elucidate the effects of Astragalus mongholicus Bunge in human neutrophils. In this study, we used isolated human neutrophils activated by various stimulants to investigate the anti-inflammatory effects of Astragalus mongholicus Bunge water extract (AWE). Cell-free assays were used to examine free radicals scavenging capabilities on superoxide anion, reactive oxygen species (ROS), and nitrogen-centered radicals. Imiquimod (IMQ) induced psoriasis-like skin inflammation mouse model was used for investigating anti-psoriatic effects. We found that AWE inhibited superoxide anion production, ROS generation, and elastase release in human neutrophils, which exhibiting a direct anti-neutrophil effect. Moreover, AWE exerted a ROS scavenging ability in the 2,2'-Azobis (2-amidinopropane) dihydrochloride assay, but not superoxide anion in the xanthine/xanthine oxidase assay, suggesting that AWE exhibited anti-oxidation and anti-inflammatory capabilities by both scavenging ROS and by directly inhibiting neutrophil activation. AWE also reduced CD11b expression and adhesion to endothelial cells in activated human neutrophils. Meanwhile, in mice with psoriasis-like skin inflammation, administration of topical AWE reduced both the affected area and the severity index score. It inhibited neutrophil infiltration, myeloperoxidase release, ROS-induced damage, and skin proliferation. In summary, AWE exhibited direct anti-inflammatory effects by inhibiting neutrophil activation and anti-psoriatic effects in mice with IMQ-induced psoriasis-like skin inflammation. Therefore, AWE could potentially be a pharmaceutical Chinese herbal medicine to inhibit neutrophilic inflammation for anti-psoriasis.

Hydroxygenkwanin Increases the Sensitivity of Liver Cancer Cells to Chemotherapy by Inhibiting DNA Damage Response in Mouse Xenograft Models.

Molecules involved in DNA damage response (DDR) are often overexpressed in cancer cells, resulting in poor responses to chemotherapy and radiotherapy. Although treatment efficacy can be improved with the concomitant use of DNA repair inhibitors, the accompanying side effects can compromise the quality of life of patients. Therefore, in this study, we identified a natural compound that could inhibit DDR, using the single-strand annealing yeast-cell analysis system, and explored its mechanisms of action and potential as a chemotherapy adjuvant in hepatocellular carcinoma (HCC) cell lines using comet assay, flow cytometry, Western blotting, immunofluorescence staining, and functional analyses. We developed a mouse model to verify the in vitro findings. We found that hydroxygenkwanin (HGK) inhibited the expression of RAD51 and progression of homologous recombination, thereby suppressing the ability of the HCC cell lines to repair DNA damage and enhancing their sensitivity to doxorubicin. HGK inhibited the phosphorylation of DNA damage checkpoint proteins, leading to apoptosis in the HCC cell lines. In the mouse xenograft model, HGK enhanced the sensitivity of liver cancer cells to doxorubicin without any physiological toxicity. Thus, HGK can inhibit DDR in liver cancer cells and mouse models, making it suitable for use as a chemotherapy adjuvant.

Growth Suppression in Lung Cancer Cells Harboring EGFR-C797S Mutation by Quercetin.

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are approved treatments for non-small-cell lung cancer (NSCLC) patients harboring activating EGFR mutations. The EGFR C797S mutation is one of the known acquired-resistance mutations to the latest third-generation TKIs. At present, there are no clear options for treating patients who acquire resistance to third-generation TKIs. The acquisition of the EGFR C797S mutation was shown to upregulate the expression of AXL, a receptor tyrosine kinase of the TAM (TYRO3-AXL-MER) family, and the suppression of AXL is effective in reducing the growth of NSCLC cells harboring EGFR C797S. As quercetin was recently shown to inhibit AXL, quercetin may be effective in treating NSCLC cells harboring the EGFR C797S mutation. In this work, the cytotoxic effects of quercetin and its ability to inhibit tumor growth were examined in TKI-resistant NSCLC cells harboring the EGFR C797S mutation. We demonstrated that quercetin exhibited potent cytotoxic effects on NSCLC cells harboring the EGFR C797S mutation by inhibiting AXL and inducing apoptosis. Quercetin inhibited the tumor growth of xenografted NSCLC cells harboring the EGFR C797S mutation and appeared to act synergistically with brigatinib to inhibit of tumor growth in vivo. In summary, herein, we revealed that quercetin is an effective inhibitor for the treatment of non-small-cell lung cancer harboring the EGFR C797S mutation.

Induction of G2/M Cell Cycle Arrest via p38/p21Waf1/Cip1-Dependent Signaling Pathway Activation by Bavachinin in Non-Small-Cell Lung Cancer Cells.

Lung cancer is the most commonly diagnosed malignant cancer in the world. Non-small-cell lung cancer (NSCLC) is the major category of lung cancer. Although effective therapies have been administered, for improving the NSCLC patient's survival, the incident rate is still high. Therefore, searching for a good strategy for preventing NSCLC is urgent. Traditional Chinese medicine (TCM) are brilliant materials for cancer chemoprevention, because of their high biological safety and low cost. Bavachinin, which is an active flavanone of Proralea corylifolia L., possesses anti-inflammation, anti-angiogenesis, and anti-cancer activities. The present study's aim was to evaluate the anti-cancer activity of bavachinin on NSCLC, and its regulating molecular mechanisms. The results exhibited that a dose-dependent decrease in the cell viability and colony formation capacity of three NSCLC cell lines, by bavachinin, were through G2/M cell cycle arrest induction. Meanwhile, the expression of the G2/M cell cycle regulators, such as cyclin B, p-cdc2Y15, p-cdc2T161, and p-wee1, was suppressed. With the dramatic up-regulation of the cyclin-dependent kinase inhibitor, p21Waf1/Cip1, the expression and association of p21Waf1/Cip1 with the cyclin B/cdc2 complex was observed. Silencing the p21Waf1/Cip1 expression significantly rescued bavachinin-induced G2/M cell accumulation. Furthermore, the expression of p21Waf1/Cip1 mRNA was up-regulated in bavachinin-treated NSCLC cells. In addition, MAPK and AKT signaling were activated in bavachinin-added NSCLC cells. Interestingly, bavachinin-induced p21Waf1/Cip1 expression was repressed after restraint p38 MAPK activation. The inhibition of p38 MAPK activation reversed bavachinin-induced p21Waf1/Cip1 mRNA expression and G2/M cell cycle arrest. Collectively, bavachinin-induced G2/M cell cycle arrest was through the p38 MAPK-mediated p21Waf1/Cip1-dependent signaling pathway in the NSCLC cells.

Imperatorin Alleviates Psoriasiform Dermatitis by Blocking Neutrophil Respiratory Burst, Adhesion, and Chemotaxis Through Selective Phosphodiesterase 4 Inhibition.

Aim: Neutrophil infiltration and increased oxidative stress are involved in the pathogenesis and severity of psoriasis. Although the therapy of psoriasis remains elusive, targeting treatment to reduce oxidative stress is considered a potential option. Our study demonstrates the anti-inflammatory effects of a natural furocoumarin, imperatorin, on activated human neutrophils and psoriasiform dermatitis in mice. Results: Imperatorin inhibited superoxide anion generation, neutrophil adhesion, and migration in N-formyl-l-methionyl-l-leucyl-l-phenylalanine (fMLF)-stimulated human neutrophils. Further studies showed that imperatorin induced a decrease in cAMP-specific phosphodiesterase (PDE) activity, and increased intracellular cAMP levels and protein kinase A (PKA) activity in human neutrophils. The enzyme activities of PDE4 subtypes, but not PDE3 and PDE7, were inhibited by imperatorin. Furthermore, imperatorin inhibited the phosphorylation of protein kinase B (Akt), extracellular regulated kinase (ERK), and c-Jun N-terminal kinase (JNK), as well as Ca2+ mobilization in fMLF-stimulated neutrophils. These suppressive effects of imperatorin on cell responses and signaling were reversed by PKA inhibitor, suggesting that cAMP/PKA is involved in the anti-inflammatory effects of imperatorin. In vivo studies of imiquimod- and interleukin-23-induced mouse psoriasiform dermatitis demonstrated that imperatorin alleviated skin desquamation, epidermal thickening, keratinocyte hyperproliferation, and neutrophil infiltration. Innovation and Conclusion: Our results demonstrate that imperatorin inhibits human neutrophil respiratory burst, adhesion, and migration through the elevation of cAMP/PKA to inhibit Akt, ERK, JNK, and Ca2+ mobilization. Imperatorin is a natural inhibitor of PDE4A/B/C and may serve as a lead for developing new therapeutics to treat neutrophilic psoriasis. Antioxid. Redox Signal. 35, 885-903.

Palbociclib induces DNA damage and inhibits DNA repair to induce cellular senescence and apoptosis in oral squamous cell carcinoma.

BACKGROUND/PURPOSE: Palbociclib is an FDA-approved cyclin-dependent kinase (CDK) 4/6 inhibitor that has been clinically proven to be effective in breast cancer. However, its use in oral cancer is not well researched. In this study, we investigated the inhibitory activity of palbociclib against oral squamous cell carcinoma (OSCC) cells and explored the mechanism of inhibition. METHODS: The effects of palbociclib on the cytotoxicity of OSCC cells were determined by MTT and colony formation assays. ß-Galactosidase staining and cell-cycle analysis were used to determine palbociclib-induced cellular senescence and apoptosis of OSCC cells. Wound healing and transwell assays were performed to assess the effects of palbociclib treatment on migration and invasion ability of OSCC cells. Whole transcriptome sequencing was conducted to show the relationship between DNA damage repair of OSCC cells and palbociclib treatment. Palbociclib-induced DNA damage and repair capacity of OSCC cells were confirmed by comet assay and immunofluorescence confocal microscopy. Western blotting was used to verify the palbociclib-mediated changes in the CDK/pRB/c-Myc/CDC25A pathway. Finally, in vitro findings were tested in a mouse xenograft model. RESULTS: Our results showed that palbociclib can significantly inhibit the growth, migration, and invasive ability of OSCC cells and can accelerate cellular senescence and apoptosis. We found that palbociclib induced DNA damage and p21 expression through the p53-independent pathway, thereby downregulating c-Myc and CDC25A expression to inhibit cell cycle progression. In addition, palbociclib downregulated RAD51 expression to inhibit DNA damage repair ability of OSCC cell. CONCLUSION: Palbociclib was found to have anti-oral squamous cell carcinoma activity and to simultaneously induce DNA damage and inhibit its repair, and to accelerated cellular senescence and apoptosis.

Corylin reduces obesity and insulin resistance and promotes adipose tissue browning through SIRT-1 and ß3-AR activation.

Brown adipose tissue (BAT) activation or beige adipocytes in white adipocytes (WAT) (browning) is a novel strategy against obesity. Corylin, a flavonoid compound extract from Psoralea corylifolia L., has been shown to exert anti-inflammatory, anticancer, and anti-atherosclerotic effects and ameliorate hyperlipidemia and insulin resistance. However, the therapeutic effect of corylin on obesity remains unknown. The objective of this study was to evaluate the effect of corylin on browning or obesity. Here, we report that corylin induced browning by elevating the expression levels of beige- or browning-specific marker genes, including cited1, hoxc9, pgc1α, prdm16, and ucp1, in 3T3-L1 adipocytes, WAT and BAT. Moreover, corylin also strikingly reduced body weight and fat accumulation and increased insulin sensitivity, mitochondrial biogenesis, and ß-oxidation in HFD- and DIO-treated mice. The browning and lipolysis effects of corylin were abolished by sirtuin 1 (SIRT1) inhibitor (EX527) and ß3-adrenergic receptor (ß3-AR) antagonist (L-748,337) treatment. The possible molecular mechanism of corylin on the browning and lipolysis of adipocytes is through SIRT1- or ß3-AR-dependent pathways. The study suggested that corylin exerts anti-obesity effects through the browning of white adipocytes, activating of BAT and promoting of lipid metabolism. Therefore, corylin may be a helpful therapeutic candidate for treating obesity.

Induction of HO-1 by 5, 8-Dihydroxy-4',7-Dimethoxyflavone via Activation of ROS/p38 MAPK/Nrf2 Attenuates Thrombin-Induced Connective Tissue Growth Factor Expression in Human Cardiac Fibroblasts.

Heme oxygenase-1 (HO-1) has been shown to exert as an antioxidant and anti-inflammatory enzyme in cardiovascular inflammatory diseases. Flavonoids have been demonstrated to display anti-inflammatory and antioxidant effects through the induction of HO-1. 5,8-Dihydroxy-4',7-dimethoxyflavone (DDF), one of the flavonoid compounds, is isolated from Reevesia formosana. Whether DDF induced HO-1 expression on human cardiac fibroblasts (HCFs) remained unknown. Here, we found that DDF time- and concentration-dependently induced HO-1 protein and mRNA expression, which was attenuated by pretreatment with reactive oxygen species (ROS) scavenger N-acetyl cysteine (NAC) in HCFs. DDF-enhanced ROS generation was attenuated by NAC, but not by either diphenyleneiodonium chloride (DPI, Nox inhibitor) or MitoTempol (mitochondrial ROS scavenger). Interestingly, pretreatment with glutathione (GSH) inhibited DDF-induced HO-1 expression. The ratio of GSH/GSSG was time-dependently decreased in DDF-treated HCFs. DDF-induced HO-1 expression was attenuated by an inhibitor of p38 MAPK (p38i VIII) or siRNA, but not by MEK1/2 (PD98059) or JNK1/2 (SP600125). DDF-stimulated p38 MAPK phosphorylation was inhibited by GSH or p38i VIII. Moreover, DDF-induced HO-1 expression was mediated through Nrf2 phosphorylation and translocation into the nucleus which was attenuated by NAC or p38 siRNA. DDF also stimulated antioxidant response element (ARE) promoter activity which was inhibited by NAC, GSH, or p38i VIII. Interaction between Nrf2 and the ARE-binding sites on the HO-1 promoter was revealed by chromatin immunoprecipitation assay, which was attenuated by NAC, GSH, or p38i VIII. We further evaluated the functional effect of HO-1 expression on the thrombin-induced fibrotic responses. Our result indicated that the induction of HO-1 by DDF can attenuate the thrombin-induced connective tissue growth factor expression. These results suggested that DDF-induced HO-1 expression is, at least, mediated through the activation of the ROS-dependent p38 MAPK/Nrf2 signaling pathway in HCFs. Thus, the upregulation of HO-1 by DDF could be a candidate for the treatment of heart fibrosis.