Lucidin 3-methyl ether from Rubia philippinensis suppresses the proliferation of multiple myeloma cells through the promotion of ß-catenin degradation.

BACKGROUND: Constitutive accumulation of ß-catenin has been frequently observed in multiple myeloma. Extracts from genus Rubia plants exhibit cytotoxic activity against several types of cancer cells; however, little is known about their chemopreventive mechanisms and bioactive metabolites. PURPOSE: Purpose: The study aimed to identify the underlying antiproliferative mechanisms of Rubia philippinensis extract in multiple myeloma cells and the major active metabolites responsible for cytotoxic activity of R. philippinensis. METHODS: The effects of R. philippinensis extracts and lucidin 3-methyl ether on the Wnt/ß-catenin pathway were determined by cell-based reporter assay, Western blot analysis, and RT-PCR. The antiproliferative activity was evaluated by cell viability assay and apoptosis analysis in RPMI8226 and MM.1S multiple myeloma cells. RESULTS: R. philippinensis extracts inhibited Wnt/ß-catenin signaling and lucidin 3-methyl ether, an anthraquinone derivative, was identified as the major active metabolite responsible for the inhibition of Wnt/ß-catenin signaling. Lucidin 3-methyl ether induced ß-catenin phosphorylation at Ser33/Ser37/Thr41 residues and promoted proteasomal degradation of ß-catenin via a GSK-3ß-independent mechanism, thereby downregulating Wnt3a-induced ß-catenin response transcription (CRT). Moreover, lucidin 3-methyl ether repressed the expression of ß-catenin/T-cell factor (TCF)-dependent genes, such as cyclin D1, c-myc, and axin-2, thus inhibiting MM cell proliferation. Apoptosis was also elicited by lucidin 3-methyl ether, as indicated by the increase in the population of annexin V-FITC positive cells and caspase-3/7 activity in MM cells. CONCLUSION: These findings indicate that R. philippinensis and its active metabolite lucidin 3-methyl ether prevent cell proliferation through the suppression of the Wnt/ß-catenin pathway and exhibit potential as chemopreventive agents for the treatment of MM.

8-Geranylumbelliferone isolated from Paramignya trimera triggers RIPK1/RIPK3-dependent programmed cell death upon TNFR1 ligation.

In tumor necrosis factor (TNF) signaling, IκB kinase (IKK) complex-mediated activation of NF-κB is a well-known protective mechanism against cell death via transcriptional induction of pro-survival genes occurring as a late checkpoint. However, recent belief holds that IKK functions as an early cell death checkpoint to suppress the death-inducing signaling complex by regulating receptor interacting protein kinase1 (RIPK1) phosphorylation. In this study, we propose that two major gernaylated 7-hydroxy coumarins, 6-geranyl-7-hydroxycoumarin (ostruthin) and 8-geranyl-7-hydroxycoumarin (8-geranylumbelliferone, 8-GU) isolated from Paramignya timera, facilitate RIPK1-dependent dual modes of apoptosis and necroptosis by targeting IKKß upon TNF receptor1 (TNFR1) ligation. Analysis of events upstream of NF-κB revealed that 8-GU and ostruthin drastically inhibited TNF-induced IKK phosphorylation, while having no effect on TAK1 phosphorylation and TNFR1 complex-I formation. Interestingly, 8-GU did not affect the cell death induced by Fas ligand or TNF-related apoptosis-inducing ligand or that induced by DNA-damaging agents, indicating that 8-GU sensitizes TNF-induced cell death exclusively. Moreover, 8-GU accelerated TNF-driven necroptosis by up-regulating necrosome formation in FADD deficient cancer cells harboring RIPK3. Thus, the present study provides new insights into the molecular mechanism underlying geranylated 7-hydroxy coumarin-mediated control of the RIPK1-dependent early cell death checkpoint and suggests that 8-GU is a potential anti-cancer therapeutic via an alternative apoptosis-independent strategy to overcome TNF resistance.

Insights into cyclooxygenase-2 inhibition by isolated bioactive compounds 3-caffeoyl-4-dihydrocaffeoyl quinic acid and isorhamnetin 3-O-ß-D-glucopyranoside from Salicornia herbacea.

BACKGROUND: Cyclooxygenase-2 (COX-2) is an important enzyme with numerous biological functions. Overexpression of COX-2 has been associated with various inflammatory-related diseases and therefore, projected as an important pharmacological target. PURPOSE: We aimed to investigate the inhibitory potential of isolated bioactive compounds, 3-caffeoyl-4-dihydrocaffeoyl quinic acid (CDQ) and isorhamnetin 3-O-ß-d-glucopyranoside (IDG), from Salicornia herbacea against COX-2 using both computational and in vitro approaches. METHODS: Computational analysis, including molecular docking, molecular dynamics (MD) simulations, and post-simulations analysis, were employed to estimate the binding affinity and stability of CDQ and IDG in the catalytic pocket of COX-2 against Celecoxib as positive control. These predictions were further evaluated using in vitro enzyme inhibition as well as gene expression mediation in macrophages cells. RESULTS: Molecular docking analysis revealed substantial binding energy of CDQ (-6.1 kcal/mol) and IDG (-5.9 kcal/mol) with COX-2, which are lower than Celecoxib (-8.1 kcal/mol). MD simulations (100 ns) and post simulation analysis exhibited the substantial stability and binding affinity of docked CDQ and IDG compounds with COX-2. In vitro assays indicated significant COX-2 inhibition by CDQ (IC50 = 76.91 ± 2.33 µM) and IDG (IC50 = 126.06 ± 9.44 µM). This result supported the inhibitory potential of isolated bioactive compounds against COX-2. Also, a cellular level study revealed a downregulation of COX-2 expression in tumor necrosis factor-alpha stimulated RAW 264.7 macrophages treated with CDQ and IDG. CONCLUSION: Computational and experimental analysis of CDQ and IDG from S. herbacea established their potential in the inhibition and mediation of COX-2. Hence, CDQ and IDG can be considered for therapeutic development against COX-2 linked disorders, such as inflammation and cancer. Furthermore, CDQ and IDG structures can be served as a lead compound for the development of advanced novel anti-inflammatory drugs.

Effects of Pelargonium sidoides and Coptis Rhizoma 2 : 1 Mixed Formula (PS + CR) on Ovalbumin-Induced Asthma in Mice.

Pelargonium sidoides (PS) is traditionally used to treat respiratory and gastrointestinal infections, dysmenorrhea, and hepatic disorders in South Africa. Coptis Rhizoma (CR) is used to treat gastroenteric disorders, cardiovascular diseases, and cancer in East Asia. In the present study, we intended to observe the possible beneficial antiasthma effects of PS and CR on the ovalbumin- (OVA-) induced asthma C57BL/6J mice. Asthma in mice was induced by OVA sensitization and subsequent boosting. PS + CR (300 and 1,000 mg/kg; PO) or dexamethasone (IP) was administered once a day for 16 days. The changes in the body weight and gains, lung weights and gross inspections, total and differential cell counts of leukocytes in bronchoalveolar lavage fluid (BALF), serum OVA-specific immunoglobulin E (OVA-sIgE) levels, interleukin-4 (IL-4) and IL-5 levels in BALF and lung tissue homogenate, and IL-4 and IL-5 mRNA levels in lung tissue homogenates were analyzed with lung histopathology: mean alveolar surface area (ASA), alveolar septal thickness, numbers of inflammatory cells, mast cells, and eosinophils infiltrated in the alveolar regions, respectively. Significant increases in lung weights, total and differential cell counts of leukocytes in BALF, serum OVA-sIgE levels, and IL-4 and IL-5 levels in BALF and lung tissue homogenate were observed in OVA control as compared to those of intact control. In addition, OVA control showed a significant decrease in mean ASA and increases in alveolar septal thickness, numbers of inflammatory cells, mast cells, and eosinophils infiltrated in alveolar regions. However, these allergic and inflammatory asthmatic changes were significantly inhibited by PS + CR in a dose-dependent manner. In this study, PS + CR showed dose-dependent beneficial effects on OVA-induced asthma in mice through anti-inflammatory and antiallergic activities. Therefore, it is expected that PS + CR have enough potential as a new therapeutic agent or as an ingredient of a medicinal agent for various allergic and inflammatory respiratory diseases including asthma.

Protective effects of Oxya chinensis sinuosa Mishchenko against ultraviolet B-induced photodamage in hairless mice.

BACKGROUND: Edible insects, including Oxya chinensis sinuosa Mishchenko (Oc), which is consumed as food in Asia, are considered as a human food shortage alternative, and also as a preventive measure against environmental destruction. Ultraviolet B (UVB) irradiation, which causes skin photodamage, is considered as an extrinsic skin aging factor. It reduces skin hydration, and increases wrinkle formation and reactive oxygen species (ROS) and inflammatory cytokine expression. Thus, the objective of this study was to investigate the anti-aging effects of an ethanol extract of Oc (Oc.Ex). METHODS: A UVB-irradiated hairless mouse model was used to examine relevant changes in skin hydration, wrinkle formation, and skin epidermal thickness. Also, antioxidant markers such as superoxide dismutase (SOD) and catalase (CAT) were analyzed, and Oc. Ex skin protective effects against UVB irradiation-induced photoaging were examined by determining the levels of skin hydration factors. RESULTS: Oc.Ex improved epidermal barrier dysfunctions such as increased transepidermal water loss (TEWL) and capacitance reduction in UVB-irradiated mice. It upregulated skin hydration-related markers, including hyaluronic acid (HA), transforming growth factor (TGF)-ß, and pro-collagen, in UVB-irradiated mice, compared with the vehicle control group. It also reduced UVB-induced wrinkle formation, collagen degradation, and epidermal thickness. Additionally, it remarkably suppressed the increased expression of matrix metalloproteinases (MMPs), and restored the activity of SOD and CAT in UVB-irradiated mice, compared with the vehicle control group. Furthermore, Oc. Ex treatment downregulated the production of inflammatory cytokines and phosphorylation of the mitogen-activated protein kinases (MAPKs) signaling pathway activated by UVB irradiation. CONCLUSION: This study revealed that Oc. Ex reduced skin thickness and the degradation of collagen fibers by increasing hydration markers and collagen-regulating factors in the skin of UVB-irradiated mice. It also inhibited UVB-induced antioxidant enzyme activity and inflammatory cytokine expression via MAPK signaling downregulation, suggesting that it prevents UVB-induced skin damage and photoaging, and has potential for clinical development in skin disease treatment.

Protopine isolated from Nandina domestica induces apoptosis and autophagy in colon cancer cells by stabilizing p53.

The tumor suppressor p53 plays essential roles in cellular protection mechanisms against a variety of stress stimuli and its activation induces apoptosis or autophagy in certain cancer cells. Here, we identified protopine, an isoquinoline alkaloid isolated from Nandina domestica, as an activator of the p53 pathway from cell-based natural compound screening based on p53-responsive transcription. Protopine increased the p53-mediated transcriptional activity and promoted p53 phosphorylation at the Ser15 residue, resulting in stabilization of p53 protein. Moreover, protopine up-regulated the expression of p21WAF1/CIP1 and BAX, downstream genes of p53, and inhibited the proliferation of HCT116 colon cancer cells. Apoptosis was elicited by protopine as indicated by caspase-3/7 activation, poly ADP ribose polymerase cleavage, and increased population of Annexin V-FITC-positive cells. Furthermore, protopine induced the formation of microtubule-associated protein 1 light chain 3 (LC3) puncta and LC3-II turnover, typical biochemical markers of autophagy, in HCT116 cells. Our findings suggest that protopine exerts its antiproliferative activity by stimulating the p53 pathway and may have potential as a chemopreventive agent for human colon cancer.

The enhancing immune response and anti-inflammatory effects of Anemarrhena asphodeloides extract in RAW 264.7 cells.

BACKGROUND: Anemarrhena asphodeloides has been widely used in traditional medicine for thousands of years; it has been reported to improve learning and memory, and to reduce inflammation. However, the role of A. asphodeloides in enhancing the immune response has remained unclear. PURPOSE: This study aimed to evaluate the effect of A. asphodeloides extract (AA-Ex) on enhancing the immune response in macrophages and to identify the active compounds causing these effects. STUDY DESIGN/METHODS: To determine the enhancing immune response of AA-Ex and its active compounds, cell proliferation and cell cycle of RAW 264.7 cells were analyzed by MTS assay and flow cytometry. The gene expression of p53, p27, cyclin D2, and cyclin E2 was measured by real-time PCR. To evaluate the anti-inflammatory effects of AA-Ex and its active compounds, the production of nitric oxide (NO), reactive oxygen species (ROS), and pro-inflammatory cytokines was analyzed by Griess reagent, flow cytometry, and real-time PCR. The phosphorylation of p38, c-Jun N-terminal kinase, inhibitory kappa B alpha, and p65 was examined by western blot analysis. RESULTS: AA-Ex increased cell proliferation by extending the cell cycle S-phase; timosaponin B and timosaponin B-II affected cell proliferation and the cell cycle as active compounds of A. asphodeloides. Next, we determined that A. asphodeloides displayed anti-inflammatory effects, including the inhibition of the production of NO, ROS, and pro-inflammatory cytokines through the suppression of mitogen-activated protein kinase and nuclear factor kappa B phosphorylation downstream of the toll-like receptor 4 signaling pathway. Moreover, we identified that timosaponin B and timosaponin B-II were the active compounds for these effects. CONCLUSION: Our results suggest that A. asphodeloides promotes the immune response and has anti-inflammatory effects. Moreover, timosaponin B and B-II played important roles as the active compounds of A. asphodeloides in enhancing the immune and anti-inflammatory responses in this model.

Hepatoprotective effects of an Acer tegmentosum Maxim extract through antioxidant activity and the regulation of autophagy.

ETHNOPHARMACOLOGICAL RELEVANCE: Acer tegmentosum Maxim (AT), the East Asian stripe maple, is an herb used to treat liver disease and is approved as a functional food in Korea. AT protects against hepatic disorders, atopic dermatitis, and diabetes mellitus. AIM OF THE STUDY: We explored the mechanism of the hepatoprotective effects of AT extract in in vitro and in vivo levels. MATERIALS AND METHODS: AT extract from Acer tegmentosum Maxim was extracted by hot water. Hepatoprotective effects of AT extract were confirmed using carbon tetrachloride (CCl4)- or alcohol-induced mouse model, and H2O2- or alcohol-induced HepG2 (liver hepatocellular carcinoma cell line) cells by measuring GOT, GPT, TG, and MDA levels. Hematoxylin and eosin (H&E) staining was used to observe the pathological analysis. Cytotoxicity or protective effect of AT extract was confirmed using MTT assay in HepG2 cells. Antioxidant effect of AT extract was measured using DPPH or H2DCFDA assay. Mechanism study of antioxidant and autophagy was carried out using western blotting and immunofluorescence analysis. RESULTS: AT extract increased the viability of HepG2 cells treated with H2O2 and ethanol, and protected the liver against damage induced by CCl4 and alcohol. The AT extract increased the levels of nuclear respiratory factor 2 (Nrf2) and heme oxygenase-1 (HO-1). The level of microtubule-associated protein light chain 3 (LC3)-Ⅱ, beclin-1, autophagy-related genes (Atg) such as Atg3 and Atg12-5 as markers of autophagy activation was also increased. Moreover, the AT extract increased activation of mitogen-activated protein kinase (MAPK), which regulated autophagy and HO-1. CONCLUSION: Therefore, these results indicate that the AT extract has a hepatoprotective effect by increasing antioxidant activity and inducing autophagy.

Pharmacokinetic study comparing pure desoxo-narchinol A and nardosinonediol with extracts from Nardostachys jatamansi.

Nardostachyos Radix et Rhizoma (NR) is a valuable medicinal herb widely used in Korea, India, and China for the treatment of many diseases. Desoxo-narchinol A (DA) and nardosinonediol (ND) are the two main bioactive compounds belonging to the sesquiterpene group. Desoxo-narchinol A possesses anti-inflammatory activity while ND exhibits anti-depressant and cardioprotective activities. A pharmacokinetic study is important to decide whether the isolated compounds or the NR extract have better pharmacological activity. Hence, we developed an analytical method for studying the pharmacokinetics of DA and ND after oral administration of the pure compounds and herbal extract. An optimized liquid chromatography-mass spectrometry method (LC-MS/MS) with solid-phase extraction (SPE) for sample preparation was developed. A ZORBAX Extend C18 column (2.1 × 50 mm, 3.5 µm) was used under gradient elution with acetonitrile and 0.1% formic acid in water as the mobile phase. Validation experiments assessing accuracy, precision, and stability were satisfactory; the lower limit of quantification was 5 ng/mL. For the pharmacokinetic study, three groups of rats were administrated pure DA, pure ND, or NR extract orally. Concentrations of DA and ND in their plasma were determined by the developed method. Pharmacokinetic parameters, including the time to achieve maximum plasma concentration (Tmax) and the area under the plasma concentration curve from time zero to infinity (AUC0-∞), were compared for the herbal extract and pure compounds. The Tmax of the pure compound and the NR extract for DA was 7.50 and 8.33 min, respectively, compared to 5.00 and 5.83 min for the pure compound and the NR extract for ND, respectively. The AUC0-∞ of the pure compound and the NR extract for DA was 156.34 and 133.90 µg min/mL, respectively, and that for the NR extract for ND was 6.42 and 4.15 µg min/mL, respectively. LC-MS/MS was used to determine DA and ND in rat plasma. The pharmacokinetic profile of each pure compound and those in the extract were characterized and compared.

C-27-carboxylated oleanane triterpenoids up-regulate TRAIL DISC assembly via p38 MAPK and CHOP-mediated DR5 expression in human glioblastoma cells.

Despite recent tremendous progress, targeting of TNF-related apoptosis-inducing ligand (TRAIL) as a cancer therapy has limited success in many clinical trials, in part due to inactivation of death inducing signaling complex (DISC)-mediated caspase-8 signaling cascade in highly malignant tumors such as glioblastoma. In this study, screening of constituents derived from Astilbe rivularis for TRAIL-sensitizing activity identified C-27-carboxylated oleanolic acid derivatives (C27OAs) including 3ß-hydroxyolean-12-en-27-oic acid (C27OA-1), 3ß,6ß,7α-trihydroxyolean-12-en-27-oic acid (C27OA-2), and 3ß-trans-p-coumaroyloxy-olean-12-en-27-oic acid (C27OA-3) as novel TRAIL sensitizers. Interestingly, these C27OAs did not affect apoptotic cell death induced by either ligation of other death receptor (DR) types, such as TNF and Fas or DNA damaging agents, which suggests that C27OAs effectively and selectively sensitize TRAIL-mediated caspase-8 activation. Mechanistically, C27OAs upregulate the expression of cell surface DR5 and DISC formation without affecting downstream intracellular apoptosis-related proteins. The upregulation of DR5 expression by C27OAs strictly depends on transactivation of C/EBP homology protein, which is regulated through the p38 MAPK pathway, rather than p53 and intracellular reactive oxygen species status. Taken together, our results identify the novel C27OAs as TRAIL sensitizers targeting the upstream DISC assembly of DR5, and provide a rationale for further development of C27OAs for facilitating TRAIL-based chemotherapy in glioblastoma patients.

Cytotoxic properties of the anthraquinone derivatives isolated from the roots of Rubia philippinensis.

BACKGROUND: Cancer is one of the most frequently occurring diseases and is the second leading cause of death worldwide. In this study, anthraquinone derivatives (Compounds 1-5) were evaluated for their anti-cancer potential against various skin and breast cancer cell lines to assess whether these anthraquinone derivatives may serve as a lead for the augmentation of anti-cancer drug. METHODS: Anthraquinone derivatives, 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone-3-O-(6'-O-acetyl)-α-rhamnosyl(1 → 2)-ß-glucoside (Comp 1), 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone (Comp 2), and alizarin (Comp 3) were isolated from the dichloromethane fraction of the roots of Rubia philippinensis., whereas ethyl acetate fraction yielded xanthopurpurin (Comp 4) and lucidin-ω-methyl ether (Comp 5). Structures of all the isolated compounds were determined by spectral data analysis. All isolated compounds (Comp 1-5) were assessed for cytotoxicity by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against four different cancer cell lines, i.e. human melanoma (SK-MEL-5), murine melanoma (B16F10), and human breast adenocarcinoma (MCF7 and MDA-MB-231). RESULTS: Significant activity of the compounds 4 and 5 was observed against the breast cancer cell line MDA-MB-231 with IC50 values of 14.65 ± 1.45 and 13.03 ± 0.33 µM, respectively. Encouragingly, IC50 values of 67.89 ± 1.02 and 79.01 ± 0.03 µM against normal kidney epithelial cells (MDCK) were also obtained for compounds 4 and 5, respectively, which indicated very low toxicity and favorable selectivity indices for compounds 4 and 5 in the range of 1.85 to 3.95 and 2.11 to 6.06 against skin cancer cell lines (SK-MEL-5, and B16F10), and breast cancer cell lines (MCF7 and MDA-MB-231), respectively. CONCLUSION: Our results suggested that the compounds 4 (xanthopurpurin) and 5 (lucidin-ω-methyl ether) showed high selective toxicity towards breast cancer cells at lower concentrations without showing toxicity towards normal cells, thus could be of potential as new lead molecules in cancer treatment.

Cucurbitane Triterpenoids from the Fruits of Momordica Charantia Improve Insulin Sensitivity and Glucose Homeostasis in Streptozotocin-Induced Diabetic Mice.

SCOPE: Momordica charantia (M. charantia) has antidiabetic effects, and cucurbitane-type triterpenoid is one of the compounds of M. charantia. This study aims to investigate whether the new cucurbitane-type triterpenoids affect insulin sensitivity both in vitro and in vivo, and the underlying mechanisms. METHODS AND RESULTS: Four compounds (C1-C4) isolated from the ethanol extract of M. charantia enhance glucose uptake in C2C12 myotubes via insulin receptor substrate-1 (IRS-1) rather than via adenosine monophosphate-activated protein kinase. The most potent, compound 2 (C2), significantly increases the activation of IRS-1 and downstream signaling pathways, resulting in glucose transporter 4 translocation. Furthermore, these C2-induced in vitro effects are blocked by specific signal inhibitors. We further evaluate the antidiabetic effect of C2 using a streptozotocin (STZ)-induced diabetic mouse model. Consistent with in vitro data, treatment with C2 (1.68 mg kg-1 ) significantly decreases blood glucose level and enhances glycogen storage in STZ-injected mice. These effects appear to be mediated by the IRS-1 signaling pathway in skeletal muscle, not in adipose and liver tissues, suggesting that C2 improves hyperglycemia by increasing glucose uptake into skeletal muscle. CONCLUSION: Our findings demonstrate that the new cucurbitane-type triterpenoids have potential for prevention and management of diabetes by improving insulin sensitivity and glucose homeostasis.

Quinoxaline-, dopamine-, and amino acid-derived metabolites from the edible insect Protaetia brevitarsis seulensis.

Edible insects have been reported to produce metabolites showing various pharmacological activities, recently emerging as rich sources of health functional food. In particular, the larvae of Protaetia brevitarsis seulensis (Kolbe) have been used as traditional Korean medicines for treating diverse diseases, such as breast cancer, inflammatory disease, hepatic cancer, liver cirrhosis, and hepatitis. However, only few chemical investigations were reported on the insect larvae. Therefore, the aim of this study was to discover and identify biologically active chemical components of the larvae of P. brevitarsis seulensis. As a result, a quinoxaline-derived alkaloid (1) was isolated, which was not reported previously from natural sources. In addition, other related compounds (2, 4-10, 15, 16) were also encountered for the first time from the larvae. The structures of all the isolated compounds were established mainly by analysis of HRESIMS, NMR, and electronic circular dichroism data. Compound 5 exhibited inhibition of tyrosinase with IC50 value of 44.8 µM.

Inhibition of Proliferation of Vascular Smooth Muscle Cells by Cucurbitanes from Momordica charantia.

The cucurbitaceous plant Momordica charantia L., named "bitter melon", inhabits Asia, Africa, and South America and has been used as a traditional medicine. The atypical proliferation of vascular smooth muscle cells (VSMCs) plays an important role in triggering the pathogenesis of cardiovascular diseases. Platelet-derived growth factor (PDGF) is regarded as the most powerful growth factor in promoting the intimal accumulation of VSMCs. The current study features the identification of six new cucurbitane-type triterpenoids (1-6) from the fruits of M.  charantia, utilizing diverse chromatographic and spectroscopic techniques. In particular, the 2D structure of 1 was confirmed utilizing the long-range HSQMBC NMR pulse, capable of measuring heteronuclear long-range correlations (4-6JCH). The cucurbitanes were also assessed for their inhibitory activity against PDGF-induced VSMC proliferation. This current study may constitute a basis for developing those chemotypes into sensible pharmacophores alleviating cardiovascular disorders.

Anti-Hyperuricemic, Anti-Inflammatory and Analgesic Effects of Siegesbeckia orientalis L. Resulting from the Fraction with High Phenolic Content.

BACKGROUND: The medicinal plant Siegesbeckia orientalis L. has been commonly used for the treatment of acute arthritis, rheumatism, and gout in Vietnam. However, pharmacological research of this plant associated with gout has not been reported. Anti-hyperuricemic and anti-inflammatory effects were evaluated and observed for the crude ethanol extract (CEE) of S. orientalis. Retention of these biological properties was found in a n-butanol-soluble fraction (BuOH fr.) of the extract, and therefore further biological and chemical investigations were undertaken on the BuOH fr. to support the medical relevance of this plant. METHODS: The aerial part of S. orientalis was obtained in the mountainous region of Vietnam. The crude ethanol extract (CEE) and its BuOH fr. were prepared from the plant materials. Anti-hyperuricemic activities of the CEE and BuOH fr. were tested in vivo using the model oxonate-induced hyperuricemia rats through determination of serum uric acid levels and inhibitory effects on xanthine oxidase (XO) in the rat liver. Anti-inflammatory activities of the BuOH fr. were also evaluated in vivo using carrageenan-induced paw edema and urate-induced synovitis in rats. Active components of the BuOH fr. were characterized by comparison of HPLC retention time (t R) and spectroscopic data (UV, 1H-NMR) with those of reference compounds. RESULTS: The CEE of S. orientalis displayed anti-hyperuricemic activity, and the BuOH fr. was found to be the most active portion of the extract. Further in vivo studies on this fraction showed 31.4% decrease of serum uric acid levels, 32.7% inhibition of xanthine oxidase (XO), 30.4% reduction of paw edema volume, symptomatic relief in urate-induced synovitis and significant analgesic effect at the dose of 120 mg/kg, as compared to the corresponding values of the control groups. Chemical analysis of the BuOH fr. revealed high phenolic content, identified as caffeic acid analogues and flavonones. CONCLUSIONS: This study suggested that anti-hyperuricemic and anti-inflammatory mechanism of S. orientalis is related to XO inhibitory effect of the phenolic components. Our findings support the use of this plant as the treatment of gout and other inflammatory diseases.

A grayanotox-9(11)-ene derivative from Rhododendron brachycarpum and its structural assignment via a protocol combining NMR and DP4 plus application.

A growing body of evidence points to the useful roles of computational approaches in the structural characterization of natural products. Rhododendron brachycarpum has been traditionally used for the control of diabetes, hepatitis, hypertension, and rheumatoid arthritis and classified as an endangered species in Korea. A grayanotox-9(11)-ene derivative along with five known diterpenoids, were isolated from the MeOH extract of R. brachycarpum. Extensive 1D and 2D NMR experiments were conducted to establish the 2D structure and relative configuration of the grayanotox-9(11)-ene derivative. Comparison of simulated and experimental ECD spectra resulted in an inconclusive outcome to assign its absolute configuration. Alternatively, gauge-including atomic orbitals (GIAO) NMR chemical shift calculations, with support by the advanced statistical method DP4 plus, and acid hydrolysis were employed to establish its absolute configuration. This work exemplifies how NMR analysis, combined with quantum mechanics calculations, is a viable approach to accomplish structural assignment of minor abundance molecules in lieu of X-ray crystallography or chiroptical approaches.

Arborinane Triterpenoids from Rubia philippinensis Inhibit Proliferation and Migration of Vascular Smooth Muscle Cells Induced by the Platelet-Derived Growth Factor.

The abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) are associated with cardiovascular diseases and related complications. Such deleterious proliferation and migration events are triggered by cytokines and growth factors, and among them, platelet-derived growth factor (PDGF) is recognized as the most potent inducer. Despite the genus Rubia being researched to identify valuable commercial and medicinal virtues, Rubia philippinensis has rarely been investigated. Nine arborinane-type triterpenoids (1-9) were identified from this underutilized plant species. In particular, 4 was identified as the first arborinane derivative carrying a ketocarbonyl motif at C-19. The presence of the cyclopentanone moiety and the associated configurational assignment were determined by utilizing NOE and coupling constant analysis. These compounds were assessed for their inhibitory potential on PDGF-induced proliferation and the migration of VSMCs. Treatment with 5 µM compound 5 (62.6 ± 10.7%) and compound 9 (41.1 ± 4.7%) impeded PDGF-stimulated proliferation without exerting cytotoxicity. Compound 7 exhibited antimigration activity in a dose-dependent manner (38.5 ± 3.0% at 10 µM, 57.6 ± 3.2% at 30 µM). These results suggest that the arborinane-type triterpenoids may be a pertinent starting point for the development of cardiovascular drugs capable of preventing the intimal accumulation of VSMCs.

Interruption of progerin-lamin A/C binding ameliorates Hutchinson-Gilford progeria syndrome phenotype.

Hutchinson-Gilford progeria syndrome (HGPS) is a rare autosomal dominant genetic disease that is caused by a silent mutation of the LMNA gene encoding lamins A and C (lamin A/C). The G608G mutation generates a more accessible splicing donor site than does WT and produces an alternatively spliced product of LMNA called progerin, which is also expressed in normal aged cells. In this study, we determined that progerin binds directly to lamin A/C and induces profound nuclear aberrations. Given this observation, we performed a random screening of a chemical library and identified 3 compounds (JH1, JH4, and JH13) that efficiently block progerin-lamin A/C binding. These 3 chemicals, particularly JH4, alleviated nuclear deformation and reversed senescence markers characteristic of HGPS cells, including growth arrest and senescence-associated ß-gal (SA-ß-gal) activity. We then used microarray-based analysis to demonstrate that JH4 is able to rescue defects of cell-cycle progression in both HGPS and aged cells. Furthermore, administration of JH4 to LmnaG609G/G609G-mutant mice, which phenocopy human HGPS, resulted in a marked improvement of several progeria phenotypes and an extended lifespan. Together, these findings indicate that specific inhibitors with the ability to block pathological progerin-lamin A/C binding may represent a promising strategy for improving lifespan and health in both HGPS and normal aging.

Antithrombotic and antiplatelet activities of small-molecule alkaloids from Scolopendra subspinipes mutilans.

The aim of this study was to discover small-molecule anticoagulants from Scolopendra subspinipes mutilans (SSM). A new acylated polyamine (1) and a new sulfated quinoline alkaloid (2) were isolated from SSM. Treatment with the new alkaloids 1, 2, and indole acetic acid 4 prolonged the activated partial thromboplastin time and prothrombin time and inhibited the activity and production of thrombin and activated factor X. Furthermore, compounds 1, 2, and 4 inhibited thrombin-catalyzed fibrin polymerization and platelet aggregation. In accordance with these potential in vitro antiplatelet activities, compounds 1, 2, and 4 showed enhanced antithrombotic effects in an in vivo pulmonary embolism and arterial thrombosis model. Compounds 1, 2, and 4 also elicited anticoagulant effects in mice. Collectively, this study may serve as the groundwork for commercializing SSM or compounds 1, 2, and 4 as functional food components for the prevention and treatment of pathogenic conditions and serve as new scaffolds for the development of anticoagulants.

Flavanones and Chromones from Salicornia herbacea Mitigate Septic Lethality via Restoration of Vascular Barrier Integrity.

Salicornia herbacea is an annual halophytic glasswort that has been employed as a culinary vegetable, salad, and traditional medicinal resource. Chemical investigation of the aerial parts of S. herbacea led to the isolation of two new (1, 2) and known (3) flavanones as well as a new nature-derived (4) and two known chromone derivatives (5, 6). These purified compounds were evaluated for their suppressive potentials against the release of high-mobility group box 1 protein (HMGB1), which has captured attention as a viable target for alleviating serious septic manifestations or septicemia. The phenolic compounds improved the survival rates of cecal ligation and puncture operation (CLP) in murine models, simulating severe septic shock and its related complications, to 40-60%. These results collectively validate that flavanone- and chromone-based secondary metabolites may serve as prospective prodrugs or food additives that may be commercialized for the control of septic complications and lethality.