Lifespan Extending and Stress Resistant Properties of Vitexin from Vigna angularis in Caenorhabditis elegans.

Several theories emphasize that aging is closely related to oxidative stress and disease. The formation of excess ROS can lead to DNA damage and the acceleration of aging. Vigna angularis is one of the important medicinal plants in Korea. We isolated vitexin from V. angularis and elucidated the lifespan-extending effect of vitexin using the Caenorhabditis elegans model system. Vitexin showed potent lifespan extensive activity and it elevated the survival rates of nematodes against the stressful environments including heat and oxidative conditions. In addition, our results showed that vitexin was able to elevate antioxidant enzyme activities of worms and reduce intracellular ROS accumulation in a dose-dependent manner. These studies demonstrated that the increased stress tolerance of vitexin-mediated nematode could be attributed to increased expressions of stress resistance proteins such as superoxide dismutase (SOD-3) and heat shock protein (HSP-16.2). In this work, we also studied whether vitexin-mediated longevity activity was associated with aging-related factors such as progeny, food intake, growth and movement. The data revealed that these factors were not affected by vitexin treatment except movement. Vitexin treatment improved the body movement of aged nematode, suggesting vitexin affects healthspan as well as lifespan of nematode. These results suggest that vitexin might be a probable candidate which could extend the human lifespan.

Genistein from Vigna angularis Extends Lifespan in Caenorhabditis elegans.

The seed of Vigna angularis has long been cultivated as a food or a folk medicine in East Asia. Genistein (4',5,7-trihydroxyisoflavone), a dietary phytoestrogen present in this plant, has been known to possess various biological properties. In this study, we investigated the possible lifespan-extending effects of genistein using Caenorhabditis elegans model system. We found that the lifespan of nematode was significantly prolonged in the presence of genistein under normal culture condition. In addition, genistein elevated the survival rate of nematode against stressful environment including heat and oxidative conditions. Further studies demonstrated that genistein-mediated increased stress tolerance of nematode could be attributed to enhanced expressions of stress resistance proteins such as superoxide dismutase (SOD-3) and heat shock protein (HSP-16.2). Moreover, we failed to find genistein-induced significant change in aging-related factors including reproduction, food intake, and growth, indicating genistein exerts longevity activity independent of affecting these factors. Genistein treatment also led to an up-regulation of locomotory ability of aged nematode, suggesting genistein affects healthspan as well as lifespan of nematode. Our results represent that genistein has beneficial effects on the lifespan of C. elegans under both of normal and stress condition via elevating expressions of stress resistance proteins.

Inhibition of adipocyte inflammation and macrophage chemotaxis by butein.

Adipose tissue inflammation has been proposed as a therapeutic target for the treatment of obesity and metabolic disorders such as insulin resistance and type 2 diabetes. Butein, a polyphenol of vegetal origin, exhibits anti-inflammatory effects in macrophages but it was not reported whether butein prevents adipocyte inflammation. Here, we investigated the effects of butein on adipocyte inflammation in 3T3-L1 cells and performed functional macrophage migration assays. Butein opposed the stimulation of inducible nitric oxide synthase (iNOS) protein expression and of nitric oxide production by simultaneous treatment of adipocytes with tumor necrosis factor alpha (TNFα), lipopolysaccharide (LPS), and interferon gamma (TLI). In addition, butein inhibited mRNA expression of pro-inflammatory genes and chemokines in adipocytes stimulated with TLI or conditioned medium from RAW 264.7 macrophages treated with LPS. These effects were associated with suppression of inhibitor of kappa B alpha degradation induced by TNFα and with nuclear factor-kappa B (NF-κB) p65 phosphorylation and acetylation. Moreover, butein prevented phosphorylation of extracellular signal-regulated kinases, c-Jun N-terminal kinase, and the mitogen-activated protein kinase (MAPK) p38. These results suggest that butein suppresses adipocyte inflammation by inhibiting NF-κB/MAPK-dependent transcriptional activity. Furthermore, conditioned media from adipocytes stimulated macrophage chemotaxis, whereas media from adipocytes treated with butein blocked macrophage migration, an effect that was consistent with suppression of MCP-1 secretion by adipocytes treated with butein. In addition, macrophages treated with butein exhibited a reduced ability to migrate toward adipocyte CM. In conclusion, butein may represent a therapeutic agent to prevent adipose tissue inflammation and the obesity-linked insulin resistance.

A novel cantharidin analog N-benzylcantharidinamide reduces the expression of MMP-9 and invasive potentials of Hep3B via inhibiting cytosolic translocation of HuR.

Invasion and metastasis are major causes of malignant tumor-associated mortality. The present study aimed to investigate the molecular events underlying inhibitory effect of N-benzylcantharidinamide, a novel synthetic analog of cantharidin, on matrix metalloproteinase-9 (MMP-9)-mediated invasion in highly metastatic hepatocellular carcinoma Hep3B cells. In this investigation, among six analogs of cantharidin, only N-benzylcantharidinamide has the inhibitory action on MMP-9 expression at non-toxic dose. The MMP-9 expression and invasion of Hep3B cells were significantly suppressed by treatment of N-benzylcantharidinamide in a dose-dependent manner. On the other hand, the transcriptional activity of MMP-9 promoter and nuclear levels of NF-κB and AP-1 as the main transcriptional factors inducing MMP-9 expression were not affected by it although the level of MMP-9 mRNA was reduced by treatment of N-benzylcantharidinamide. Interestingly, the stability of MMP-9 mRNA was significantly reduced by N-benzylcantharidinamide-treatment. In addition, the cytosolic translocation of human antigen R (HuR), which results in the increase of MMP-9 mRNA stability through interaction of HuR with 3'-untranslated region of MMP-9 mRNA, was suppressed by treatment of N-benzylcantharidinamide, in a dose-dependent manner. Taken together, it was demonstrated, for the first time, that N-benzylcantharidinamide suppresses MMP-9 expression by reducing HuR-mediated MMP-9 mRNA stability for the inhibition of invasive potential in highly metastatic Hep3B cells.

Synthesis and characterization of G5 PAMAM dendrimer containing daunorubicin for targeting cancer cells.

A multifunctional dendritic nanodevice containing folate (FA) as the targeting molecule and daunorubicin (DNR) as the chemotherapeutic drug has been designed and synthesized. The primary amino groups on the surface of the generation 5 poly(amidoamine) dendrimer (G5 dendrimer) were acetylated partially. FA and DNR were conjugated to the remaining primary amino groups on the G5 dendrimer through amide and ester linkage, respectively, to generate the difunctional dendritic device. The synthetic approach of G5 PAMAM dendrimer containing daunorubicin and folic acid would be useful for targeting the overexpressed membrance-associated folate receptors of KB human carcinoma cell line and discreating them effectively.

Repeated Administration of Korea Red Ginseng Extract Increases Non-Rapid Eye Movement Sleep via GABAAergic Systems.

The current inquiry was conducted to assess the change in sleep architecture after long periods of administration to determine whether ginseng can be used in the therapy of sleeplessness. Following post-surgical recovery, red ginseng extract (RGE, 200 mg/ kg) was orally administrated to rats for 9 d. Data were gathered on the 1st, 5th, and 9th day, and an electroencephalogram was recorded 24 h after RGE administration. Polygraphic signs of unobstructed sleep-wake activities were simultaneously recorded with sleep-wake recording electrodes from 11:00 a.m. to 5:00 p.m. for 6 h. Rodents were generally tamed to freely moving polygraphic recording conditions. Although the 1st and 5th day of RGE treatment showed no effect on power densities in non-rapid eye movement (NREM) and rapid eye movement (REM) sleep, the 9th day of RGE administration showed augmented α-wave (8.0 to 13.0 Hz) power densities in NREM and REM sleep. RGE increased total sleep and NREM sleep. The total percentage of wakefulness was only decreased on the 9th day, and the number of sleep-wake cycles was reduced after the repeated administration of RGE. Thus, the repeated administration of RGE increased NREM sleep in rats. The α-wave activities in the cortical electroencephalograms were increased in sleep architecture by RGE. Moreover, the levels of both α- and ß-subunits of the γ-aminobutyric acid (GABA)A receptor were reduced in the hypothalamus of the RGE-treated groups. The level of glutamic acid decarboxylase was over-expressed in the hypothalamus. These results demonstrate that RGE increases NREM sleep via GABAAergic systems.

Isopsoralen Induces Differentiation of Prechondrogenic ATDC5 Cells via Activation of MAP Kinases and BMP-2 Signaling Pathways.

Endochondral bone formation is the process by which mesenchymal cells condense to become chondrocytes, which ultimately form new bone. The process of chondrogenic differentiation and hypertrophy is critical for bone formation and as such is regulated by many factors. In this study, we aimed to indentify novel factors that regulate chondrogenesis. We investigated the possible role of isopsoralen in induction of chondrogenic differentiation in clonal mouse chondrogenic ATDC5 cells. Isopsoralen treatment stimulated the accumulation of cartilage nodules in a dose-dependent manner. Further, ATDC5 cells treated with isopsoralen were stained more intensely with Alcian blue than control cells, suggesting that isopsoralen increases the synthesis of matrix proteoglycans. Similarly, isopsoralen markedly induced the activation of alkaline phosphatase activity compared with control cells. Isopsoralen enhanced the expressions of chondrogenic marker genes such as collagen II, collagen X, OCN, Smad4 and Sox9 in a time-dependent manner. Furthermore, isopsoralen induced the activation of extracellular signal-regulated kinase (ERK) and p38 MAP kinase, but not that of c-jun N-terminal kinase (JNK). Isopsoralen significantly enhanced the protein expression of BMP-2 in a time-dependent manner. PD98059 and SB 203580, inhibitors of ERK and p38 MAPK, respectively, decreased the number of stained cells treated with isopsoralen. Taken together, these results suggest that isopsoralen mediates a chondromodulating effect by BMP-2 or MAPK signaling pathways, and is therefore a possible therapeutic agent for bone growth disorders.

Anti-metastatic properties of the leaves of Eriobotrya japonica.

The leaves of Eriobotrya japonica Lindl. have been widely used as a traditional medicine for the treatment of many diseases including gastroenteric disorders, diabetes mellitus, chronic bronchitis and asthma. In the present study, the anti-metastatic action of the EtOAc fraction of the leaves of E. japonica (LEJ) was investigated. LEJ showed potent inhibitory effects on MMP-2 and MMP-9 activities and expressions via down-regulation of NF-κB translocation to the nucleus in B16F10 cells. In addition, the cell migration and invasion were down-regulated by LEJ. LEJ also significantly suppressed lung metastasis in vivo. Moreover, we isolated the compounds ursolic acid and 2α-hydroxyursolic acid from LEJ and both compounds also significantly suppressed MMP-2 and MMP-9 activities, indicating that they are the active components of LEJ. The present results demonstrate that LEJ may be used as valuable antimetastatic agent for the treatment of cancer metastasis.

Pharmacokinetics and biodistribution of paclitaxel loaded in pegylated solid lipid nanoparticles after intravenous administration.

In an effort to develop an alternative formulation of paclitaxel (PTX) suitable for intravenous administration, PTX-loaded sterically stabilized solid lipid nanoparticles (SLNs) were prepared and their pharmacokinetics and biodistribution were investigated. The pegylated SLNs were comprised of trimyristin (TM) as a solid lipid core and egg phosphatidylcholine and pegylated phospholipid as stabilizers. The prepared pegylated TM-SLNs containing PTX exhibited monodispersed size distribution with 217.4 ± 32.8 nm of mean diameter and 99% of distribution was smaller than 556.2 ± 89.9 nm. After PTX in the pegylated TM-SLNs or commercial product, Taxol®, was intravenously administered into femoral vein of rats, concentrations of PTX in plasma and organs such as liver, spleen, kidney, heart and lung were analyzed by HPLC following liquid extraction. Plasma profile of PTX for pegylated TM-SLNs was similar to that for Taxol®, with no statistically significant difference at each time point, although mean plasma levels of PTX at each point tended to be slightly lower in pegylated TM-SLNs than in Taxol®. PTX in the pegylated TM-SLNs was taken up mainly into reticuloendothelial system showing 8-fold and 3-fold higher levels in liver and spleen, respectively, 8 h after administration compared to PTX in Taxol®. Meanwhile, PTX levels in kidney, heart and lung were not different between two formulations. There were no statistically significant differences in pharmacokinetic parameters. Taken together the results, the pegylated TM-SLNs provided similar circulation compared with commercial formulation, Taxol®.

Ethanol Extract of the Flower Chrysanthemum morifolium Augments Pentobarbital-Induced Sleep Behaviors: Involvement of Cl Channel Activation.

Dried Chrysanthemum morifolium flowers have traditionally been used in Korea for the treatment of insomnia. This study was performed to investigate whether the ethanol extract of Chrysanthemum morifolium flowers (EFC) enhances pentobarbital-induced sleep behaviors. EFC prolonged sleep time induced by pentobarbital similar to muscimol, a GABA(A) receptors agonist. EFC also increased sleep rate and sleep time when administrated with pentobarbital at a subhypnotic dosage. Both EFC and pentobarbital increased chloride (Cl(-)) influx in primary cultured cerebellar granule cells. EFC increased glutamic acid decarboxylase (GAD) expression levels, but had no effect on the expression of α1-, ß2-, and γ2-subunits of the GABA(A) receptor in the hippocampus of a mouse brain. This is in contrast to treatment with pentobarbital, which showed decreased α1-subunit expression and no change in GAD expression. In conclusion, EFC augments pentobarbital-induced sleep behaviors; these effects may result from Cl(-) channel activation.

Anti-inflammatory and antinociceptive properties of the leaves of Eriobotrya japonica.

AIM OF THE STUDY: The leaves of Eriobotrya japonica Lindl. have been widely used as a traditional medicine for the treatment of many diseases including coughs and asthma. The present study was designed to validate the anti-inflammatory and antinociceptive properties of the n-BuOH fraction of E. japonica (LEJ) leaves. MATERIALS AND METHODS: The anti-inflammatory properties of LEJ were studied using IFN-γ/LPS activated murine peritoneal macrophage model. The antinociceptive effects of LEJ were assessed using experimental models of pain, including thermal nociception methods, such as the tail immersion test and the hotplate test, and chemical nociception induced by intraperitoneal acetic acid and subplantar formalin in mice. To examine the possible connection of the opioid receptor to the antinociceptive activity of LEJ, we performed a combination test with naloxone, a nonselective opioid receptor antagonist. RESULTS: In the IFN-γ and LPS-activated murine peritoneal macrophage model, LEJ suppressed NO production and iNOS expression via down-regulation of NF-κB activation. It also attenuated the expression of COX-2 and the secretion of pro-inflammatory cytokines like TNF-α and IL-6. Moreover, LEJ also demonstrated strong and dose-dependent antinociceptive activity compared to tramadol and indomethacin in various experimental pain models. In a combination test using naloxone, diminished analgesic activities of LEJ were observed, indicating that the antinociceptive activity of LEJ is connected with the opioid receptor. CONCLUSIONS: The results indicate that LEJ had potent inhibitory effects on the inflammatory mediators including nitric oxide, iNOS, COX-2, TNF-α and IL-6 via the attenuation of NF-κB translocation to the nucleus. LEJ also showed excellent antinociceptive activity in both central and peripheral mechanism as a weak opioid agonist. Based on these results, LEJ may possibly be used as an anti-inflammatory and an analgesic agent for the treatment of pains and inflammatory diseases.

(-)-Epigallocatethin-3-O-gallate counteracts caffeine-induced hyperactivity: evidence of dopaminergic blockade.

This experiment was designed to know whether (-)-epigallocatethin-3-O-gallate (EGCG) counteracts caffeine-induced hyperactivity, and its potential mechanisms in mice. EGCG inhibited methamphetamine-induced, cocaine-induced and caffeine-induced horizontal hyperlocomotion and rearing activity. EGCG also inhibited hyperlocomotion and rearing activity induced by apomorphine, a D1/D2-like agonist. Moreover, EGCG inhibited climbing behavior, a typical stereotyped behavior induced by stimulation of dopamine receptors through the activation of those receptors by apomorphine. From this experiment, we suggest that EGCG inhibits hyperactivity induced by psychostimulants including caffeine, in part by modulating dopaminergic transmission, and these inhibitory effects of EGCG counteract the stimulant actions of caffeine in green tea.

Effects of isolated compounds from Catalpa ovata on the T cell-mediated immune responses and proliferation of leukemic cells.

Three compounds were isolated from the ethyl acetate soluble fraction of the methanolic extract of the leaves of Catalpa ovata (Bignoniaceae) through repeated column chromatography. We investigated the effects of these compounds on T cell-mediated responses for tumor surveillance and proliferation in U937, HL60, and Molt-4 leukemia cells. Compounds 1-3 inhibited proliferation of those cells in a dose-dependent manner. Compound 3 showed mild effect in Molt-4 cell cytotoxicity. Compound 3 enhanced gene expressions of p53 and IL-4, but decreased IL-2 and IFN-Gamma genes in Molt-4 cell. Our findings indicate that compound 3 may enhance T cell-mediated immune responses and anticancer properties.

Methanol extract of Longanae Arillus augments pentobarbital-induced sleep behaviors through the modification of GABAergic systems.

This experiment was performed to investigate whether methanol extract of Longanae Arillus (MELA) has hypnotic effects and/or enhances pentobarbital-induced sleep behaviors through the GABAergic systems. MELA prolonged sleep time and reduced sleep latency induced by pentobarbital similar to muscimol, a GABAA receptors agonist. MELA also increased sleep rate and sleep time in the combined administration with pentobarbital at the sub-hypnotic dosage and showed synergic effects with muscimol in potentiating sleep onset and enhancing sleep time induced by pentobarbital. However, MELA itself did not induce sleep at higher dose which was used in this experiment. In addition, both of MELA and pentobarbital increased chloride influx in primary cultured cerebellar granule cells. MELA increased GABAA receptors gamma-subunit expression and had no effect on the expression of alpha- and beta-subunits, and glutamic acid decarboxylase (GAD) in primary cultured cerebellar granule cells, showing different expression of subunits from pentobarbital. In conclusion, MELA itself does not induce sleep, but it augments pentobarbital-induced sleep behaviors through the modification of GABAergic systems.

Hexane-Soluble Fraction of the Common Fig, Ficus carica, Inhibits Osteoclast Differentiation in Murine Bone Marrow-Derived Macrophages and RAW 264.7 Cells.

Osteoclasts, derived from multipotent myeloid progenitor cells, play homeostatic roles in skeletal modeling and remodeling, but may also destroy bone in pathological conditions such as osteoporosis and rheumatoid arthritis. Osteoclast development depends critically on a differentiation factor, the receptor activator of NF-kappaB ligand (RANKL). In this study, we found that the hexane soluble fraction of the common fig Ficus carica (HF6-FC) is a potent inhibitor of osteoclastogenesis in RANKL-stimulated RAW264.7 cells and in bone marrow-derived macrophages (BMMs). HF6-FC exerts its inhibitory effects by suppression of p38 and NF-kappaB but activation of ERK. In addition, HF6-FC significantly decreased the expression of NFATc1 and c-Fos, the master regulator of osteoclast differentiation. The data indicate that components of HF6-FC may have therapeutic effects on bone-destructive processes such as osteoporosis, rheumatoid arthritis, and periodontal bone resorption.

Facile synthesis of hydroxy wilfordic acid, a esterifying unit of anti-HIV sesquiterpene pyridine alkaloids.

Sesquiterpene pyridine alkaloids were isolated mainly from plants of the genus Tripterygium (Celastraceae) which have been used traditionally in Chinese medicine. These compounds have polyhydroxy dihydro-beta-agarofuran core and esterifying substituent with dilactone bridges, and recently demonstrated promising anti-HIV activity. We have achieved the synthesis of hydroxy wilfordic acid and its ester via asymmetric cyanosilylation. With a NMR study of (S)- and (R)-PGME (phenylglycine methyl ester) amide, the tertiary alcohol stereochemistry of synthetic hydroxyl wilfordic acids was determined. Our synthetic approach will provide a contribution to the synthesis of sesquiterpene pyridine alkaloids and the development of their analogs for anti-HIV activity.

Anxiolytic-like effects of sanjoinine A isolated from Zizyphi Spinosi Semen: possible involvement of GABAergic transmission.

This experiment was performed to investigate the anxiolytic-like effects of sanjoinine A, one of the major alkaloid compounds in Zizyphi Spinosi Semen (ZSS), by using experimental paradigms of anxiety in comparison with a known anxiolytic, diazepam. Sanjoinine A (2.0 mg/kg) increased the percentage of time spent on the open arms and the number of open arms entries in the elevated plus-maze test, increased the number of head dips in the hole-board test, and increased the percentage of time spent in the center zone and the center zone locomotor distance in the open field box experiment. However, sanjoinine A (0.5, 1.0, 2.0 mg/kg) had no effect on locomotor activity, while diazepam (2.0 mg/kg) significantly reduced locomotor activity. Sanjoinine A (0.5, 1.0, 2.0 mg/kg) did not influence the grip force in the grip strength meter test either. Molecular experiments showed that sanjoinine A (2.0, 5.0 microM) increased chloride influx in cultured cerebellar granule cells. In addition, sanjoinine A (5.0 microM) treatment resulted in over-expression of alpha- and gamma-subunits of GABA(A) receptors and glutamic acid decarboxylase (GAD65/67) in cultured cerebellar granule cells. It is concluded that sanjoinine A may have anxiolytic-like effects in the elevated plus-maze, hole-board test and open field test, and these effects may be mediated by GABAergic transmission.

Ikarisoside A inhibits inducible nitric oxide synthase in lipopolysaccharide-stimulated RAW 264.7 cells via p38 kinase and nuclear factor-kappaB signaling pathways.

This study examined the anti-inflammatory properties of Ikarisoside A, isolated from Epimedium koreanum (Berberidaceae), in lipopolysaccharide (LPS)-stimulated macrophages. Ikarisoside A inhibited the expression of LPS-stimulated inducible nitric oxide synthase (iNOS) and the production of nitric oxide (NO) in LPS-stimulated RAW 264.7 cells and mouse bone marrow-derived macrophages (BMMs) in a concentration-dependent manner. In addition, Ikarisoside A reduced the release of pro-inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta). Furthermore, Ikarisoside A inhibited the activity of p38 kinase and nuclear factor-kappaB (NF-kappaB), which are signaling molecules involved in NO production. NO production was inhibited when the cells were treated with LPS and either SB 203580 (a p38 inhibitor) or Bay 11-7082 (an inhibitory kappaB kinase 2 inhibitor). These results suggest that Ikarisoside A inhibits the production of NO by inhibiting the activity of p38 MAPK and NF-kappaB. As a result of these properties, Ikarisoside A has the potential to be used as an effective anti-inflammatory agent.

Prostaglandin E2-mediated dysregulation of proinflammatory cytokine production in pristane-induced lupus mice.

Systemic lupus erythematosus (SLE) is characterized by inflammatory and dysregulatory immune responses including overactive B cells, overproduction of proinflammatory cytokines, and T cell hyperactivity. PGE(2) modulates a variety of immune processes at sites of inflammation, including production of inflammatory cytokines. However, the role of PGE(2) in dysregulatory inflammatory and immune responses in lupus remains unclear. We investigated whether PGE(2) mediates production of inflammatory cytokines in pristane-induced lupus BALB/c mice. Our results showed that levels of serum and BAL PGE(2) and LPS-stimulated production of PGE(2) by peritoneal macrophages were remarkably increased in pristane-induced lupus mice compared to healthy controls. Exogenous PGE(2) enhanced production of IL-6, IL-10, and NO but decreased TNF-alpha by macrophages and augmented IFN-gamma, IL-6, and IL-10 by splenocytes from pristane-induced lupus mice compared to healthy controls. Exogenous PGE(2) also enhanced production of IFN-gamma, IL-6, and IL-10 by thymocytes from pristane-induced lupus mice. Indomethacin (Indo), a PGE(2) synthesis inhibitor, greatly inhibited LPS-induced production of IL-6 and IL-10 by macrophages from pristane-induced lupus mice, while enhanced TNF-alpha. Indo remarkably inhibited Con A-increased production of IFN-gamma, IL-6, and IL-10 by splenocytes and thymocytes from pristane-induced lupus mice. Therefore, our findings suggest that endogenous PGE(2) may mediate dysregulation of production of proinflammatory cytokines, such as IL-6, IL-10, and IFN-gamma, and NO in pristane-induced lupus mice.

Icariside II from Epimedium koreanum inhibits hypoxia-inducible factor-1alpha in human osteosarcoma cells.

Hypoxia-inducible factor-1 (HIF-1) is an important tumor-selective therapeutic target for solid tumors. Icariside II was isolated from Epimedium koreanum through successive fractionation with ethyl acetate, n-butanol, chloroform and hexane, followed by gel column chromatography. Icariside II attenuated the protein level of HIF-1alpha induced by hypoxia in human osteosarcoma (HOS) cells in a concentration-dependent manner, probably by enhancing the interaction rate between von Hippel-Lindau (VHL) and HIF-1alpha. Furthermore, Icariside II down-regulated the levels of HIF-inducible genes involved in angiogenesis, metastasis, and glucose metabolism, such as vascular endothelial growth factor (VEGF), urokinase plasminogen activator receptor (uPAR), adrenomedullin (ADM), matrix metalloproteinase 2 (MMP2), aldolase A, and enolase 1 in HOS cells. Icariside II also inhibited the migration rate in HOS cells and tube formation rate in human umbilical vein endothelium cells (HUVECs). Overall, these results suggest the potential use of Icariside II as a therapeutic candidate against various diseases that involve overexpression of HIF-1alpha.