A Lignan from Alnus japonica Activates Myogenesis and Alleviates Dexamethasone-induced Myotube Atrophy.

To find inhibitors against skeletal muscle loss, we isolated a lignan compound ((-)-(2R,3R-1,4-O-diferuloylsecoisolarciresinol, DFS) from the stem of Alnus japonica. C2C12 myoblasts were treated with DFS during differentiation. To induce an in vitro atrophic condition, differentiated myotubes were treated with dexamethasone (a synthetic glucocorticoid). DFS (10 nM) increased expression levels of myogenic factors and the number of multi-nucleated myotubes expressing myosin heavy chain (MHC). The myogenic potential of DFS could be attributed to p38 MAPK activation. DFS also protected against dexamethasone-induced damage, showing increased expression of MHC and mammalian target of rapamycin (mTOR), a major anabolic factor. Under atrophic condition, the anti-myopathy effect of DFS was associated with inactivation of NF-κB signaling pathway and the subsequent suppression of muscle degradative E3 ligases and myostatin. DFS treatment also restored fast muscle fiber (type II a, II b, and II x), known to be susceptible to dexamethasone. These results indicate that DFS isolated from A. japonica can stimulate myogenesis via p38 MAPK activation and alleviate muscle atrophy by modulating the expression of genes associated with muscle protein anabolism/catabolism. Thus, we propose that DFS can be used as a pharmacological and nutraceutical agent for increasing muscle strength or protecting muscle loss.

Sesquiterpenes from Artemisia princeps regulate inflammatory responses in RAW 264.7 macrophages.

Four sesquiterpenoids were isolated from an ethyl acetate-soluble fraction of A. princeps ethanolic extract: seco-tanapartholide B (5-epi-seco-tanapartholide A) (1), 4-epi-seco-tanapartholide A (2), 11,13-dehydrodesacetylmatricarin (3) and desacetylmatricarin (4). Compounds 1 - 3 dose-dependently inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-activated macrophages. These compounds also decreased mRNA and protein expression levels of inducible NO synthase and cyclooxygenase-2 as well as mRNA levels of pro-inflammatory cytokines (interleukin-1ß and tumour necrosis factor-α) in LPS-stimulated RAW 264.7 macrophages. Moreover, compound 3 effectively enhanced the expression of heme oxygenase-1 (HO-1) in macrophages in the presence or absence of LPS. Additionally, the exocyclic methylene of α-methylene-γ-lactone moiety of compound 3 was found to be essential for the activation of the NF erythroid 2-related factor 2 (Nrf2)/HO-1 pathway. Here, we firstly report the isolation of compounds 3 and 4 from A. princeps and the anti-inflammatory activity of compound 3 by up-regulation of Nrf2/HO-1 pathway.

A lignan from Alnus japonica inhibits glioblastoma tumorspheres by suppression of FOXM1.

Forkhead Box M1 (FOXM1) is known to regulate cell proliferation, apoptosis and tumorigenesis. The lignan, (-)-(2R,3R)-1,4-O-diferuloylsecoisolariciresinol (DFS), from Alnus japonica has shown anti-cancer effects against colon cancer cells by suppressing FOXM1. The present study hypothesized that DFS can have anti-cancer effects against glioblastoma (GBM) tumorspheres (TSs). Immunoprecipitation and luciferase reporter assays were performed to evaluate the ability of DFS to suppress nuclear translocation of ß-catenin through ß-catenin/FOXM1 binding. DFS-pretreated GBM TSs were evaluated to assess the ability of DFS to inhibit GBM TSs and their transcriptional profiles. The in vivo efficacy was examined in orthotopic xenograft models of GBM. Expression of FOXM1 was higher in GBM than in normal tissues. DFS-induced FOXM1 protein degradation blocked ß-catenin translocation into the nucleus and consequently suppressed downstream target genes of FOXM1 pathways. DFS inhibited cell viability and ATP levels, while increasing apoptosis, and it reduced tumorsphere formation and the invasiveness of GBM TSs. And DFS reduced the activities of transcription factors related to tumorigenesis, stemness, and invasiveness. DFS significantly inhibited tumor growth and prolonged the survival rate of mice in orthotopic xenograft models of GBM. It suggests that DFS inhibits the proliferation of GBM TSs by suppressing FOXM1. DFS may be a potential therapeutic agent to treat GBM.

Angelica keiskei Root Extract Attenuates Bile Duct Ligation-Induced Liver Injury in Mice.

Although multiple studies have shown that Angelica keiskei of the Umbelliferae family has potent anti-inflammatory and antioxidative activities and that it reduces the serum bile acids in humans, whether A. keiskei has protective effects against cholestasis-induced liver injury remains unexplored until now. This study tests the hypothesis that Angelica keiskei root extract (AKE) alleviates liver injury, inflammation, and fibrosis in mouse models of acute cholestasis induced by bile duct ligation (BDL). Oral administration of AKE (200 or 500 mg/kg) attenuated hepatocellular necrosis and significantly reduced serum levels of bile acids and bilirubin in BDL mice. The critical enzyme of bile acid synthesis, CYP7A1, was repressed by AKE, suggesting that reduced bile acid production may contribute to liver protection. Moreover, we determined through gene expression and cytokine analysis and histological examination that AKE treatment decreased liver inflammation, oxidative stress, and fibrosis. AKE also suppressed the NF-κB pathway, suggesting this as a possible mediator of its anti-inflammatory effect. Our findings substantiate that AKE may be promising for treating cholestatic liver diseases in the future.

Kazinol C from Broussonetia kazinoki stimulates autophagy via endoplasmic reticulum stress-mediated signaling.

Autophagy modulators are considered putative therapeutic targets because of the role of autophagy in cancer progression. Kazinol C, a 1,3-diphenylpropane from the plant Broussonetia kazinoki, has been shown to induce apoptosis in colon cancer cells through the activation of AMPK at high concentrations. In the present study, we found that Kazinol C induced autophagy through endoplasmic reticulum stress-mediated unfolded protein response signaling in several normal and cancer cell lines at low concentrations of Kazinol C that did not induce apoptosis. Kazinol C activated the transducers of unfolded protein response signaling, leading to target gene expression, LC3-II conversion, and TFEB nuclear translocation. Chemical inhibition of endoplasmic reticulum stress reduced LC3-II conversion. In addition, blockade of autophagy by knockout of Atg5 or treatment with 3-MA enhanced Kazinol C-induced apoptosis. In summary, we have uncovered Kazinol C as a novel autophagy inducer and confirmed the role of autophagy as a cellular stress protector.

Urushiol V Suppresses Cell Proliferation and Enhances Antitumor Activity of 5-FU in Human Colon Cancer Cells by Downregulating FoxM1.

Colorectal cancer (CRC) is one of the most common malignant tumor. 5-FU is commonly used for the treatment of CRC. However, the development of drug resistance in tumor chemotherapy can seriously reduce therapeutic efficacy of 5-FU. Recent data show that FoxM1 is associated with 5-FU resistance in CRC. FoxM1 plays a critical role in the carcinogenesis and drug resistance of several malignancies. It has been reported that urushiol V isolated from the cortex of Rhus verniciflua Stokes is cytotoxic to several types of cancer cells. However, the underlying molecular mechanisms for its antitumor activity and its potential to attenuate the chemotherapeutic resistance in CRC cells remain unknown. Here, we found that urushiol V could inhibit the cell proliferation and induced S-phase arrest of SW480 colon cancer cells. It inhibited protein expression level of FoxM1 through activation of AMPK. We also investigated the combined effect of urushiol V and 5-FU. The combination treatment reduced FoxM1 expression and consequently reduced cell growth and colony formation in 5-FU resistant colon cancer cells (SW480/5-FUR). Taken together, these result suggest that urushiol V from Rhus verniciflua Stokes can suppress cell proliferation by inhibiting FoxM1 and enhance the antitumor capacity of 5-FU. Therefore, urushiol V may be a potential bioactive compound for CRC therapy.

Structure-Activity Relationship of Phytoestrogen Analogs as ERα/ß Agonists with Neuroprotective Activities.

A set of isoflavononid and flavonoid analogs was prepared and evaluated for estrogen receptor α (ERα) and ERß transactivation and anti-neuroinflammatory activities. Structure-activity relationship (SAR) study of naturally occurring phytoestrogens, their metabolites, and related isoflavone analogs revealed the importance of the C-ring of isoflavonoids for ER activity and selectivity. Docking study suggested putative binding modes of daidzein 2 and dehydroequol 8 in the active site of ERα and ERß, and provided an understanding of the promising activity and selectivity of dehydroequol 8. Among the tested compounds, equol 7 and dehydroequol 8 were the most potent ERα/ß agonists with ERß selectivity and neuroprotective activity. This study provides knowledge on the SAR of isoflavonoids for further development of potent and selective ER agonists with neuroprotective potential.

Discovery of 5-Phenoxy-2-aminopyridine Derivatives as Potent and Selective Irreversible Inhibitors of Bruton's Tyrosine Kinase.

As a member of the tyrosine protein kinase Tec (TEC) family, Bruton's tyrosine kinase (BTK) is considered a promising therapeutic target due to its crucial roles in the B cell receptor (BCR) signaling pathway. Although many types of BTK inhibitors have been reported, there is an unmet need to achieve selective BTK inhibitors to reduce side effects. To obtain BTK selectivity and efficacy, we designed a novel series of type II BTK inhibitors which can occupy the allosteric pocket induced by the DFG-out conformation and introduced an electrophilic warhead for targeting Cys481. In this article, we have described the structure-activity relationships (SARs) leading to a novel series of potent and selective piperazine and tetrahydroisoquinoline linked 5-phenoxy-2-aminopyridine irreversible inhibitors of BTK. Compound 18g showed good potency and selectivity, and its biological activity was evaluated in hematological tumor cell lines. The in vivo efficacy of 18g was also tested in a Raji xenograft mouse model, and it significantly reduced tumor size, with 46.8% inhibition compared with vehicle. Therefore, we have presented the novel, potent, and selective irreversible inhibitor 18g as a type II BTK inhibitor.

Discovery of Tricyclic Pyranochromenone as Novel Bruton's Tyrosine Kinase Inhibitors with in Vivo Antirheumatic Activity.

Bruton's tyrosine kinase (BTK) is an attractive target for treating patients with B cell malignancies and autoimmune diseases. Many BTK inhibitors have been identified; however, like other kinase inhibitors, they lack diversity in their core structures. Therefore, it is important to secure a novel scaffold that occupies the adenine-binding site of BTK. We screened an in-house library of natural products and their analogs via a biochemical assay to identify a novel scaffold for targeting BTK. A pyranochromenone scaffold, derived from a natural active component decursin, was found to be effective at targeting BTK and was selected for further optimization. A series of pyranochromenone analogs was synthesized through the modification of pyranochromenone at the C7 position. Pyranochromenone compounds with an electrophilic warhead exhibited promising BTK inhibitory activity, with IC50 values in the range of 0.5-0.9 µM. A docking study of the representative compound 8 provided a reasonable explanation for compound activity. Compound 8 demonstrated good selectivity over other associated kinases and decreased the production of proinflammatory cytokines in THP cells. Moreover, compound 8 presented significant in vivo efficacy in a murine model of collagen-induced arthritis.

A novel nucleolin-binding peptide for Cancer Theranostics.

Background: Cancer-specific ligands have been of great interest as pharmaceutical carriers due to the potential for site-specific delivery. In particular, cancer-specific peptides have many advantages over nanoparticles and antibodies, including high biocompatibility, low immunogenicity, and the formation of nontoxic metabolites. The goal of the present study was the development of a novel cancer-specific ligand. Methods: Cancer-specific peptide ligands were screened using a one-bead-one-compound (OBOC) combinatorial method combined with a multiple-antigen-peptide (MAP) synthesis method. The specificity of the peptide ligands toward cancer cells was tested in vitro using a whole-cell binding assay, flow cytometry, and fluorescence confocal microscopy. The tissue distribution profile and therapeutic efficacy of a paclitaxel (PTX)-conjugated peptide ligand was assessed in vivo using xenograft mouse models. Results: We discovered that AGM-330 specifically bound to cancer cells in vitro and in vivo. Treatment with PTX-conjugated AGM-330 dramatically inhibited cancer cell growth in vitro and in vivo compared to treatment with PTX alone. The results of pull-down assay and LC-MS/MS analyses showed that membrane nucleolin (NCL) was the target protein of AGM-330. Although NCL is known as a nuclear protein, we observed that it was overexpressed on the membranes of cancer cells. In particular, membrane NCL neutralization inhibited growth in cancer cells in vitro. Conclusions: In summary, our findings indicated that NCL-targeting AGM-330 has great potential for use in cancer diagnosis and targeted drug delivery in cancer therapy.

Tussilagone promotes osteoclast apoptosis and prevents estrogen deficiency-induced osteoporosis in mice.

Osteoporosis is a degenerative disease characterized by reduced bone mass, in which deregulated bone remodeling by osteoclasts and osteoblasts is a main pathogenesis. Although recently tussilagone, a major active component of flower buds of Tussilago farfara, has been shown to inhibit osteoclastogenesis, its effect on estrogen deficiency-induced osteoporosis remains unknown. This study examined the effect of tussilagone on bone loss in ovariectomized mice and further explored its impact on osteoclast apoptosis and osteoblast formation in addition to osteoclastogenesis. Tussilagone suppression of osteoclastogenesis was confirmed in bone marrow derived macrophages, which was observed with the 1/10 concentration of that of the previous study. As demonstrated by ApoPercentage dye staining and Western blotting, tussilagone enhanced apoptosis in differentiated osteoclasts by increasing estrogen receptor α and Fas ligand expression. On the contrary, either osteoblast differentiation or mineralization was not affected by tussilagone. Lastly, administering tussilagone to mice for 6 weeks prevented trabecular microarchitecture impairment in ovariectomized mice compared to vehicle control groups. These findings suggest that tussilagone or Tussilago farfara prevents osteoporotic bone loss by suppressing osteoclast differentiation and inducing osteoclast apoptosis, and that it may therefore offer a possible remedy against resorptive bone diseases.

Lignan from Alnus japonica Inhibits Adipocyte Differentiation via Cell Cycle and FOXO1 Regulation.

In the present study, we isolated a lignan ((-)-(2R,3R)-1,4-O-diferuloylsecoisolariciresinol, DFS) from Alnus japonica and evaluated its antiobesity potential in vitro. We also determined its mechanism of action in a mouse pre-adipocyte 3T3-L1 cell line. DFS dose- and day-dependently inhibited adipogenesis by downregulation of adipogenic factors and lipid metabolism-regulating factors during adipocyte differentiation. In particular, DFS suppressed cell cycle-regulating factors and induced G0/G1 cell cycle arrest, implying that it had an inhibitory effect on mitotic clonal expansion which occurred at an early stage of adipogenesis. DFS also suppressed adipogenesis through decreasing Akt phosphorylation and increasing the level of Forkhead box protein-O1 (FOXO1). These results suggest that DFS may be a pharmacological candidate for the development of antiobesity, therapeutic, and nutraceutical products.

Broussoflavonol B from Broussonetia kazinoki Siebold Exerts Anti-Pancreatic Cancer Activity through Downregulating FoxM1.

Pancreatic cancer has a high mortality rate due to poor rates of early diagnosis. One tumor suppressor gene in particular, p53, is frequently mutated in pancreatic cancer, and mutations in p53 can inactivate normal wild type p53 activity and increase expression of transcription factor forkhead box M1 (FoxM1). Overexpression of FoxM1 accelerates cellular proliferation and cancer progression. Therefore, inhibition of FoxM1 represents a therapeutic strategy for treating pancreatic cancer. Broussoflavonol B (BF-B), isolated from the stem bark of Broussonetia kazinoki Siebold has previously been shown to inhibit the growth of breast cancer cells. This study aimed to investigate whether BF-B exhibits anti-pancreatic cancer activity and if so, identify the underlying mechanism. BF-B reduced cell proliferation, induced cell cycle arrest, and inhibited cell migration and invasion of human pancreatic cancer PANC-1 cells (p53 mutated). Interestingly, BF-B down-regulated FoxM1 expression at both the mRNA and protein level. It also suppressed the expression of FoxM1 downstream target genes, such as cyclin D1, cyclin B1, and survivin. Cell cycle analysis showed that BF-B induced the arrest of G0/G1 phase. BF-B reduced the phosphorylation of extracellular signal-regulated kinase ½ (ERK½) and expression of ERK½ downstream effector c-Myc, which regulates cell proliferation. Furthermore, BF-B inhibited cell migration and invasion, which are downstream functional properties of FoxM1. These results suggested that BF-B could repress pancreatic cancer cell proliferation by inactivation of the ERK/c-Myc/FoxM1 signaling pathway. Broussoflavonol B from Broussonetia kazinoki Siebold may represent a novel chemo-therapeutic agent for pancreatic cancer.

Inhibition of autophagy sensitizes lignan-induced endoplasmic reticulum stress-mediated cell death.

Relationship between autophagy and endoplasmic reticulum (ER) stress and their application to treat cancer have been actively studied these days. Recently, a lignan [(-)-(2R, 3R)-1,4-O-diferuloylsecoisolariciresinol, DFS] from Alnus japonica has been found to reduce the viability of colon cancer cells. In this study, we have observed DFS-induced autophagy in a variety of cancer cell lines. In addition, DFS led to ER stress, based on the activation of unfolded protein response (UPR) transducers and an elevated expression of UPR target genes in prostate and colon cancer cells. Further investigation has shown that DFS triggered the activation of AMP-activated protein kinase (AMPK) signaling and nuclear translocation of transcription factor EB (TFEB). Furthermore, the cytotoxicity of DFS was potentiated by the co-treatment of autophagy inhibitor in these cancer cells. This study has provided a noble implication that the combination of DFS and autophagy inhibition exerts a synergistic effect in cancer treatment.

Corylifol A from Psoralea corylifolia L. Enhances Myogenesis and Alleviates Muscle Atrophy.

Inflammatory conditions caused by cancer, chronic diseases or aging can lead to skeletal muscle atrophy. We identified myogenic compounds from Psoralea corylifolia (PC), a medicinal plant that has been used for the treatment of inflammatory and skin diseases. C2C12 mouse skeletal myoblasts were differentiated in the presence of eight compounds isolated from PC to evaluate their myogenic potential. Among them, corylifol A showed the strongest transactivation of MyoD and increased expression of myogenic markers, such as MyoD, myogenin and myosin heavy chain (MHC). Corylifol A increased the number of multinucleated and MHC-expressing myotubes. We also found that the p38 MAPK signaling pathway is essential for the myogenic action of corylifol A. Atrophic condition was induced by treatment with dexamethasone. Corylifol A protected against dexamethasone-induced myotube loss by increasing the proportion of multinucleated MHC-expressing myotubes compared with dexamethasone-damaged myotubes. Corylifol A reduced the expression of muscle-specific ubiquitin-E3 ligases (MAFbx and MuRF1) and myostatin, while activating Akt. These dual effects of corylifol A, inhibition of catabolic and activation of anabolic pathways, protect myotubes against dexamethasone damage. In summary, corylifol A isolated from P. corylifolia alleviates muscle atrophic condition through activating myoblast differentiation and suppressing muscle degradation in atrophic conditions.

Z-Ajoene Inhibits Growth of Colon Cancer by Promotion of CK1α Dependent ß-Catenin Phosphorylation.

Aberrant activation of a Wnt/ß-catenin pathway results in nuclear accumulation of ß-catenin in colon cancer. Inhibiting ß-catenin is one strategy for treating colon cancer. Here, we identified Z-ajoene, a sulfur containing compound isolated from crushed garlic, as an inhibitor of colon cancer cell growth. Z-Ajoene repressed ß-catenin response transcriptional activity, intracellular ß-catenin levels, and its representative target protein levels (c-Myc and cyclin D1) in SW480 colon cancer cells. To clarify the regulatory mechanism of decreased ß-catenin levels, we examined the effect of Z-ajoene on ß-catenin phosphorylation, which is involved in ß-catenin degradation. Z-Ajoene promoted the phosphorylation of ß-catenin at Ser45 in a casein kinase 1α (CK1α)-dependent manner, which is an essential step in ß-catenin degradation in the cytosol. These findings indicate that Z-ajoene from garlic may be a potential chemotherapeutic agent by modulating CK1α activity and the Wnt/ß-catenin signaling pathway.

Undulatory topographical waves for flow-induced foulant sweeping.

Diverse bioinspired antifouling strategies have demonstrated effective fouling-resistant properties with good biocompatibility, sustainability, and long-term activity. However, previous studies on bioinspired antifouling materials have mainly focused on material aspects or static architectures of nature without serious consideration of kinetic topographies or dynamic motion. Here, we propose a magnetically responsive multilayered composite that can generate coordinated, undulatory topographical waves with controlled length and time scales as a new class of dynamic antifouling materials. The undulatory surface waves of the dynamic composite induce local and global vortices near the material surface and thereby sweep away foulants from the surface, fundamentally inhibiting their initial attachment. As a result, the dynamic composite material with undulating topographical waves provides an effective means for efficient suppression of biofilm formation without surface modification with chemical moieties or nanoscale architectures.

Z-ajoene from Crushed Garlic Alleviates Cancer-Induced Skeletal Muscle Atrophy.

Skeletal muscle atrophy is one of the major symptoms of cancer cachexia. Garlic (Allium sativum), one of the world's most commonly used and versatile herbs, has been employed for the prevention and treatment of diverse diseases for centuries. In the present study, we found that ajoene, a sulfur compound found in crushed garlic, exhibits protective effects against muscle atrophy. Using CT26 tumor-bearing BALB/c mice, we demonstrate in vivo that ajoene extract alleviated muscle degradation by decreasing not only myokines secretion but also janus kinase/signal transducer and activator of transcription 3 (JAK/STAT3) and SMADs/forkhead box (FoxO) signaling pathways, thereby suppressing muscle-specific E3 ligases. In mouse skeletal myoblasts, Z-ajoene enhanced myogenesis as evidenced by increased expression of myogenic markers via p38 mitogen-activated protein kinase (MAPK) activation. In mature myotubes, Z-ajoene protected against muscle protein degradation induced by conditioned media from CT26 colon carcinoma cells, by suppressing expression of muscle specific E3 ligases and nuclear transcription factor kappa B (NF-κB) phosphorylation which contribute to muscle atrophy. Moreover, Z-ajoene treatment improved myofiber formation via stimulation of muscle protein synthesis. These findings suggest that ajoene extract and Z-ajoene can attenuate skeletal muscle atrophy induced by cancer cachexia through suppressing inflammatory responses and the muscle wasting as well as by promoting muscle protein synthesis.

Correction to: Cinnamon extract induces tumor cell death through inhibition of NFκB and AP1.

Following publication of the original article [1], the authors have re-evaluated the authorship for this article. The updated author group is.

A Chalcone from Ashitaba (Angelica keiskei) Stimulates Myoblast Differentiation and Inhibits Dexamethasone-Induced Muscle Atrophy.

Ashitaba, Angelica keiskei Koidzumi (AK), as a traditional medicine in Korea, Japan, and China, has been known as an elixir of life having therapeutic potential. However, there is no scientific evidence to support that Ashitaba can enhance or maintain muscle strength. To find a new therapeutic agent from the medicinal plant, we evaluated the anti-myopathy effect of chalcones from ethanol extract of AK (EAK) in cellular and animal models of muscle atrophy. To examine anti-myopathy activity, EAK was treated into dexamethasone injected rats and muscle thickness and histopathological images were analyzed. Oral administration of EAK (250 or 500 mg/kg) alleviated muscle atrophic damages and down-regulated the mRNA levels of muscle-specific ubiquitin-E3 ligases. Among ten compounds isolated from EAK, 4-hydroxyderricin was the most effective principle in stimulating myogenesis of C2C12 myoblasts via activation of p38 mitogen-activated protein kinase (MAPK). In three cellular muscle atrophy models with C2C12 myoblasts damaged by dexamethasone or cancer cell-conditioned medium, 4-hydroxyderricin protected the myosin heavy chain (MHC) degradation through suppressing expressions of MAFbx, MuRF-1 and myostatin. These results suggest that the ethanol extract and its active principle, 4-hydroxyderricin from AK, can overcome the muscle atrophy through double mechanisms of decreasing muscle protein degradation and activating myoblast differentiation.