Science.gov

Sample records for potent anticariogenic activity

  1. Anticariogenic Activity of Black Tea - An Invivo Study

    PubMed Central

    Arya, Vishal; Srivastava, Ankit; Nandlal, Swati

    2016-01-01

    Introduction Teas is known for its anticariogenic properties and various mechanisms have been invoked to explain this effect. One such proposed mechanism is inhibition of salivary alpha amylase activity by endogenous tannins present in tea. Aim The objective of the present study was to determine whether or not the ingestion of black tea decoction inhibits the enzyme salivary amylase and thus interferes with the release of maltose from intraoral entrapped particles of food. Materials and Methods A total of 30 children in the age group of 12 - 15 years were selected for the study. After two hours of fasting subjects consumed two salted crackers for 60 second following which they rinsed with water (control solution) and then with 1.5% black tea decoction (test solution) next day. Retained food particles were recovered from buccal aspect of left mandibular premolar and salivary amylase activity was noted via chromatography. Paired t-test was applied for statistical analysis. Results Maltose to Sucrose ratio was used to evaluate the result. The average ratio was 3.27 for control solution and 1.82 for test solution. The results were statistically highly significant (p <0.005). Conclusion Tea inhibited the activity of salivary amylase and this inhibition assumes a special significance when it is considered that the effect of tea could be manifested over a prolonged period of time, as in a real life situation. PMID:27135007

  2. Anticariogenic activity and phytochemical studies of crude extract from some Indian plant leaves

    PubMed Central

    Barad, Mahesh K.; Ishnava, Kalpesh B.; Chauhan, Jenabhai B.

    2014-01-01

    Aim: The aim was to screen the selected Indian plants for their antibacterial efficacy against four cariogenic bacteria Lactobacillus acidophilus (LA)(Microbial Type Culture Collection [MTCC]-*447), Lactobacillus casei (LC) (MTCC-1423), Streptococcus mutans (SMU) (MTCC-890) and Staphylococcus aureus (MTCC-96). To identify and characterize active principle present in these plants for the treatment of dental caries. Materials and Methods: The dried plant leaves materials are extracted by cold extraction using hexane, ethyl acetate, methanol, and distilled water. The solvents were evaporated, and the dried masses were suspended in dimethyl sulfoxide and used for anticariogenic activity by agar well diffusion method. Minimum inhibitory concentration (MIC) was evaluated by two-fold serial broth dilution method. Preliminary phytochemical analysis of effective extract was carried out by thin-layer chromatography (TLC) and bioautography. Results: Ethyl acetate and hexane extract of Eucalyptus globules was found most effective against L. acidophilus with MIC value 31 μg/ml and 62 μg/ml, respectively. Ethyl acetate extracts of Acacia nilotica and methanolic extract of E. globules also exhibited antibacterial activity against SMU and L. casei with MIC value of 50 μg/ml. Qualitative analysis of E. globules revealed the presence of alkaloids, terpenoids, phenolic compounds, and cardiac glycosides. The active principle responsible for the anticariogenic activity from E. globules were separated by TLC and subjected to bioautography using SMU, LA and LC. Conclusion: Anticariogenic activity and preliminary phytochemical analysis revealed that E. globule have potential to treat dental caries. PMID:26401353

  3. Anticariogenic activity of macelignan isolated from Myristica fragrans (nutmeg) against Streptococcus mutans.

    PubMed

    Chung, J Y; Choo, J H; Lee, M H; Hwang, J K

    2006-03-01

    The occurrence of dental caries is mainly associated with oral pathogens, especially cariogenic Streptococcus mutans. Preliminary antibacterial screening revealed that the extract of Myristica fragrans, widely cultivated for the spice and flavor of foods, possessed strong inhibitory activity against S. mutans. The anticariogenic compound was successfully isolated from the methanol extract of M. fragrans by repeated silica gel chromatography, and its structure was identified as macelignan by instrumental analysis using 1D-NMR, 2D-NMR and EI-MS. The minimum inhibitory concentration (MIC) of macelignan against S. mutans was 3.9 microg/ml, which was much lower than those of other natural anticariogenic agents such as 15.6 microg/ml of sanguinarine, 250 microg/ml of eucalyptol, 500 microg/ml of menthol and thymol, and 1000 microg/ml of methyl salicylate. Macelignan also possessed preferential activity against other oral microorganisms such as Streptococcus sobrinus, Streptococcus salivarius, Streptococcus sanguis, Lactobacillus acidophilus and Lactobacillus casei in the MIC range of 2-31.3 microg/ml. In particular, the bactericidal test showed that macelignan, at a concentration of 20 microg/ml, completely inactivated S. mutans in 1 min. The specific activity and fast-effectiveness of macelignan against oral bacteria strongly suggest that it could be employed as a natural antibacterial agent in functional foods or oral care products.

  4. Variation in total polyphenolics contents of aerial parts of Potentilla species and their anticariogenic activity.

    PubMed

    Tomczyk, Michał; Pleszczyńska, Małgorzata; Wiater, Adrian

    2010-07-01

    The aerial parts of selected Potentilla species (P. anserina, P. argentea, P. erecta, P. fruticosa, P. grandiflora, P. nepalensis, P. norvegica, P. pensylvanica, P. crantzii and P. thuringiaca) were investigated in order to determine their contents of polyphenolic compounds. The results showed that P. fruticosa has relatively high concentrations of tannins (167.3 +/- 2.0 mg/g dw), proanthocyanidins (4.6 +/- 0.2 mg/g dw) and phenolic acids (16.4 +/- 0.8 mg/g dw), as well as flavonoids (7.0 +/- 1.1 mg/g dw), calculated as quercetin. Furthermore, we investigated the in vitro inhibitory effects of aqueous extracts from these species against cariogenic Streptococcus spp. strains. It was found that the tested samples moderately inhibit the growth of oral streptococci. However, all the preparations exhibited inhibitory effects on water-insoluble alpha-(1-->3)-, alpha-(1-->6)-linked glucan (mutan) and artificial dental plaque formation. The extract from P. fruticosa showed the highest anti-biofilm activities, with minimum mutan and biofilm inhibition concentrations of 6.25-25 and 50-100 microg/mL, respectively. The results indicate that the studied Potentilla species could be a potential plant material for extracting biologically active compounds, and could become a useful supplement for pharmaceutical products as a new anticariogenic agent in a wide range of oral care products. PMID:20657382

  5. Anti-cariogenic and anti-biofilms activity of Tunisian propolis extract and its potential protective effect against cancer cells proliferation.

    PubMed

    Kouidhi, Bochra; Zmantar, Tarek; Bakhrouf, Amina

    2010-12-01

    Propolis is a multifunctional substance used by bees to maintain the safety of their hives. It is worldwide used for its potential therapeutic effects. In this study, Tunisian propolis ethanol extract (EEP) was tested for their anti-cariogenic, anti-biofilms and antiproliferative effects of many cell lines. The Tunisian EEP was evaluated in vitro against 33 oral pathogens including streptococci and enterococci using broth microdilution method. The anti-biofilms activity of EEP was assessed via Crystal Violet staining and MTT assays. The Tunisian EEP antiproliferative effect was evaluated on normal (MRC-5) and cancer cell lines (HT-29, A549, Hep-2, raw 264.7, Vero) by the ability of the cells to metabolically reduce MTT to a formazan dye. Our results revealed that Tunisian EEP possessed excellent protective effects against cariogenic and biofilms activity of oral streptococci. Furthermore, EEP showed a strong antiproliferative potencies against all studied cancer cell lines as judged by IC50 and its value ranges from 15.7 ± 3.4 to 200 ± 22.2 μg mL⁻¹. These results suggest that EEP is able to inhibit cancer cell proliferation, cariogenic bacteria and oral biofilms formation. It could have a promising role in the future medicine and nutrition when used as antibiotic or food additive.

  6. Salivaricin E and abundant dextranase activity may contribute to the anti-cariogenic potential of the probiotic candidate Streptococcus salivarius JH.

    PubMed

    Walker, Glenn V; Heng, Nicholas C K; Carne, Alan; Tagg, John R; Wescombe, Philip A

    2016-03-01

    Dental caries is an infectious disease that is continuing to increase in prevalence, reducing the quality of life for millions worldwide as well as causing considerable expense, with an estimated US$108 billion spent on dental care in the USA each year. Oral probiotics are now being investigated to determine whether they could play a role in the prevention and treatment of this disease. Streptococcus salivarius strain JH is a potential probiotic candidate that produces multiple proteinaceous antimicrobials (bacteriocins), the inhibitory spectrum of which includes Streptococcus mutans, one of the principal causative agents of dental caries. The genome of strain JH has previously been shown to contain the biosynthetic loci for the bacteriocins salivaricin A3, streptin and streptococcin SA-FF22. Here we show that strain JH also produces salivaricin E, a 32 aa lantibiotic with a mass of 3565.9 Da, which is responsible for the inhibition of S. mutans growth. In addition, strain JH was shown to produce dextranase, an enzyme that hydrolyses (1 → 6)-α-D-glucosidic linkages, at levels higher than any other S. salivarius tested. In vitro testing showed that partial hydrolysis of the exopolymeric substances of S. mutans, using strain JH dextranase, improved the anti-S. mutans inhibitory activity of the lytic bacteriocin, zoocin A. The multiple bacteriocin and dextranase activities of strain JH support its candidature for development as an oral probiotic.

  7. Salivaricin E and abundant dextranase activity may contribute to the anti-cariogenic potential of the probiotic candidate Streptococcus salivarius JH.

    PubMed

    Walker, Glenn V; Heng, Nicholas C K; Carne, Alan; Tagg, John R; Wescombe, Philip A

    2016-03-01

    Dental caries is an infectious disease that is continuing to increase in prevalence, reducing the quality of life for millions worldwide as well as causing considerable expense, with an estimated US$108 billion spent on dental care in the USA each year. Oral probiotics are now being investigated to determine whether they could play a role in the prevention and treatment of this disease. Streptococcus salivarius strain JH is a potential probiotic candidate that produces multiple proteinaceous antimicrobials (bacteriocins), the inhibitory spectrum of which includes Streptococcus mutans, one of the principal causative agents of dental caries. The genome of strain JH has previously been shown to contain the biosynthetic loci for the bacteriocins salivaricin A3, streptin and streptococcin SA-FF22. Here we show that strain JH also produces salivaricin E, a 32 aa lantibiotic with a mass of 3565.9 Da, which is responsible for the inhibition of S. mutans growth. In addition, strain JH was shown to produce dextranase, an enzyme that hydrolyses (1 → 6)-α-D-glucosidic linkages, at levels higher than any other S. salivarius tested. In vitro testing showed that partial hydrolysis of the exopolymeric substances of S. mutans, using strain JH dextranase, improved the anti-S. mutans inhibitory activity of the lytic bacteriocin, zoocin A. The multiple bacteriocin and dextranase activities of strain JH support its candidature for development as an oral probiotic. PMID:26744310

  8. In vitro anticariogenic effects of aerial parts of Potentilla recta and its phytochemical profile.

    PubMed

    Tomczyk, Michał; Wiater, Adrian; Pleszczyńska, Małgorzata

    2011-03-01

    This study, for the first time, investigated the in vitro inhibitory effects of Potentilla recta extracts and subfractions obtained with solvents of different polarity (aqueous, 50% ethanol, diethyl ether, ethyl acetate and n-butanol) against cariogenic Streptococcus spp. strains. It was found that the tested samples inhibited the growth of oral streptococci. Furthermore, all five P. recta preparations exhibited an inhibitory effect on water-insoluble α-(1→3)-,α-(1→6)-linked glucan (mutan) and artificial dental plaque formation. The ethyl acetate fraction showed the highest antibiofilm activities especially against S. sobrinus GCM 20381, with minimum mutan and biofilm inhibition concentrations of 6.25 and 25 µg/mL, respectively. The phytochemical profile of active constituents in the investigated samples was analysed. The high polyphenolics (total phenol, phenolic acids, tannins, proantocyanidins, flavonoids) content were found. The ethyl acetate fraction showed the highest concentration of total polyphenol content which may correlate with the high cariogenic activity of this subfraction. The results demonstrate that P. recta extracts and subfractions could become useful supplements for pharmaceutical products as new anticariogenic agents in a wide range of oral care products. Further studies are necessary to clarify the precise bioactive constituents of P. recta responsible for the anticariogenic properties. PMID:20677176

  9. Enteromorpha compressa Exhibits Potent Antioxidant Activity

    PubMed Central

    Shanab, Sanaa M. M.; Shalaby, Emad A.; El-Fayoumy, Eman A.

    2011-01-01

    The green macroalgae, Enteromorpha compressa (Linnaeus) Nees, Ulva lactuca, and E. linza, were seasonally collected from Abu Qir bay at Alexandria (Mediterranean Sea) This work aimed to investigate the seasonal environmental conditions, controlling the green algal growth, predominance, or disappearance and determining antioxidant activity. The freshly collected selected alga (E. compressa) was subjected to pigment analysis (chlorophyll and carotenoids) essential oil and antioxidant enzyme determination (ascorbate oxidase and catalase). The air-dried ground alga was extracted with ethanol (crude extract) then sequentially fractionated by organic solvents of increasing polarity (petroleum ether, chloroform, ethyl acetate, and water). Antioxidant activity of all extracts was assayed using different methods (total antioxidant, DPPH [2, 2 diphenyl-1-picrylhydrazyl], ABTS [2, 2 azino-bis ethylbenzthiazoline-6-sulfonic acid], and reducing power, and β-carotene linoleic acid bleaching methods). The results indicated that the antioxidant activity was concentration and time dependent. Ethyl acetate fraction demonstrated higher antioxidant activity against DPPH method (82.80%) compared to the synthetic standard butylated hydroxyl toluene (BHT, 88.5%). However, the crude ethanolic extract, pet ether, chloroform fractions recorded lower to moderate antioxidant activities (49.0, 66.0, and 78.0%, resp.). Using chromatographic and spectroscopic analyses, an active compound was separated and identified from the promising ethyl acetate fraction. PMID:21869863

  10. Potent Antiscrapie Activities of Degenerate Phosphorothioate Oligonucleotides

    PubMed Central

    Kocisko, David A.; Vaillant, Andrew; Lee, Kil Sun; Arnold, Kevin M.; Bertholet, Nadine; Race, Richard E.; Olsen, Emily A.; Juteau, Jean-Marc; Caughey, Byron

    2006-01-01

    Although transmissible spongiform encephalopathies (TSEs) are incurable, a key therapeutic approach is prevention of conversion of the normal, protease-sensitive form of prion protein (PrP-sen) to the disease-specific protease-resistant form of prion protein (PrP-res). Here degenerate phosphorothioate oligonucleotides (PS-ONs) are introduced as low-nM PrP-res conversion inhibitors with strong antiscrapie activities in vivo. Comparisons of various PS-ON analogs indicated that hydrophobicity and size were important, while base composition was only minimally influential. PS-ONs bound avidly to PrP-sen but could be displaced by sulfated glycan PrP-res inhibitors, indicating the presence of overlapping binding sites. Labeled PS-ONs also bound to PrP-sen on live cells and were internalized. This binding likely accounts for the antiscrapie activity. Prophylactic PS-ON treatments more than tripled scrapie survival periods in mice. Survival times also increased when PS-ONs were mixed with scrapie brain inoculum. With these antiscrapie activities and their much lower anticoagulant activities than that of pentosan polysulfate, degenerate PS-ONs are attractive new compounds for the treatment of TSEs. PMID:16495266

  11. Potent Antibacterial Activity of Copper Embedded into Silicone and Polyurethane.

    PubMed

    Sehmi, Sandeep K; Noimark, Sacha; Weiner, Jonathan; Allan, Elaine; MacRobert, Alexander J; Parkin, Ivan P

    2015-10-21

    A simple, easily up-scalable swell-encapsulation-shrink technique was used to incorporate small 2.5 nm copper nanoparticles (CuNPs) into two widely used medical grade polymers, polyurethane, and silicone, with no significant impact on polymer coloration. Both medical grade polymers with incorporated CuNPs demonstrated potent antimicrobial activity against the clinically relevant bacteria, methicillin-resistant Staphylococcus aureus and Escherichia coli. CuNP-incorporated silicone samples displayed potent antibacterial activity against both bacteria within 6 h. CuNP-incorporated polyurethane exhibited more efficacious antimicrobial activity, resulting in a 99.9% reduction in the numbers of both bacteria within just 2 h. With the high prevalence of hospital-acquired infections, the use of antimicrobial materials such as these CuNP-incorporated polymers could contribute to reducing microbial contamination associated with frequently touched surfaces in and around hospital wards (e.g., bed rails, overbed tables, push plates, etc.).

  12. Potent Antioxidant Dendrimers Lacking Pro-oxidant Activity

    PubMed Central

    Lee, Choon Young; Sharma, Ajit; Uzarski, Rebecca L.; Cheong, Jae Eun; Xu, Hao; Held, Rich A.; Upadhaya, Samik K.; Nelson, Julie L.

    2010-01-01

    It is well known that antioxidants have protective effects against oxidative stress. Unfortunately, in the presence of transition metals, antioxidants including polyphenols with potent antioxidant activities may also exhibit pro-oxidant effects, which may irreversibly damage DNA. Therefore, antioxidants with strong free radical scavenging abilities and devoid of pro-oxidant effects would be of immense biological importance. We report two antioxidant dendrimers with a surface rich in multiple phenolic hydroxyl groups, benzylic hydrogens and electron donating ring substituents that contribute to their potent free radical quenching property. In order to minimize their pro-oxidant effects, the dendrimers were designed with a metal chelating tris(2-aminoethyl)amine (TREN) core. The dendritic antioxidants were prepared by attachment of six syringaldehyde or vanillin molecules to TREN by reductive amination. They exhibited potent radical scavenging properties: 5 times stronger than quercetin and 15 times more potent than Trolox according to the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The antioxidant dendrimers also protected low-density lipoprotein, lysozyme and DNA against 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced free radical damage. More importantly, unlike quercetin and Trolox, the two TREN antioxidant dendrimers did not damage DNA via their pro-oxidant effects when incubated with physiological amounts of copper ions. The dendrimers also showed no cytotoxicity towards Chinese hamster ovary cells. PMID:20977937

  13. Synthesis and Potent Antimalarial Activity of Kalihinol B

    PubMed Central

    2016-01-01

    Of the 50+ kalihinane diterpenoids reported to date, only five had been tested for antimalarial activity, in spite of the fact that kalihinol A is the most potent among the members of the larger family of antimalarial isocyanoterpenes. We have validated a strategy designed to access many of the kalihinanes with a 12-step enantioselective synthesis of kalihinol B, the tetrahydrofuran isomer of kalihinol A (a tetrahydropyran). Kalihinol B shows similarly high potency against chloroquine-resistant Plasmodium falciparum. PMID:25815413

  14. Anti-cariogenic effects of polyphenols from plant stimulant beverages (cocoa, coffee, tea).

    PubMed

    Ferrazzano, Gianmaria F; Amato, Ivana; Ingenito, Aniello; De Natale, Antonino; Pollio, Antonino

    2009-07-01

    Polyphenols occurring in cocoa, coffee and tea can have a role in the prevention of cariogenic processes, due to their antibacterial action. Cocoa polyphenol pentamers significantly reduce biofilm formation and acid production by Streptococcus mutans and S. sanguinis. In the same way, trigonelline, caffeine and chlorogenic acid occurring in green and roasted coffee interfere with S. mutans adsorption to saliva-coated hydroxyapatite beads. Studies carried out on green, oolong and black tea indicate that tea polyphenols exert an anti-caries effect via an anti-microbial mode-of-action, and galloyl esters of (-)-epicatechin, (-)-epigallocatechin and (-)-gallocatechin show increasing antibacterial activities. The anti-cariogenic effects against alpha-haemolytic streptococci showed by polyphenols from cocoa, coffee, and tea suggest further studies to a possible application of these beverages in the prevention of pathogenesis of dental caries.

  15. Deoxygedunin, a natural product with potent neurotrophic activity in mice.

    PubMed

    Jang, Sung-Wuk; Liu, Xia; Chan, Chi Bun; France, Stefan A; Sayeed, Iqbal; Tang, Wenxue; Lin, Xi; Xiao, Ge; Andero, Raul; Chang, Qiang; Ressler, Kerry J; Ye, Keqiang

    2010-01-01

    Gedunin, a family of natural products from the Indian neem tree, possess a variety of biological activities. Here we report the discovery of deoxygedunin, which activates the mouse TrkB receptor and its downstream signaling cascades. Deoxygedunin is orally available and activates TrkB in mouse brain in a BDNF-independent way. Strikingly, it prevents the degeneration of vestibular ganglion in BDNF -/- pups. Moreover, deoxygedunin robustly protects rat neurons from cell death in a TrkB-dependent manner. Further, administration of deoxygedunin into mice displays potent neuroprotective, anti-depressant and learning enhancement effects, all of which are mediated by the TrkB receptor. Hence, deoxygedunin imitates BDNF's biological activities through activating TrkB, providing a powerful therapeutic tool for treatment of various neurological diseases. PMID:20644624

  16. ANTICARIOGENIC POTENCIAL OF ACIDULATE SOLUTIONS WITH LOW FLUORIDE CONCENTRATION

    PubMed Central

    Delbem, Alberto Carlos Botazzo; Tiano, Gilberto Carlos; Alves, Karina Mirela Ribeiro Pinto; Cunha, Robson Frederico

    2006-01-01

    Objectives: The aim of this study was to verify the anticariogenic effect of acidulate solutions with low NaF concentration, using pH-cycling model and bovine enamel. Material and methods: Enamel blocks were submitted to the surface microhardness (SMH) test and randomly divided in 12 experimental and one placebo groups. The blocks were submitted to pH cycling for 7 days, with daily applications once/day of 0.05% NaF and 0.1% NaF and twice/day of 0.02% NaF solutions. Four different pH: 4.0, 5.0, 6.0 and 7.0 were used. Next, SMH test was again used to determine the surface microhardness percentage change (%SMH). Data obtained for %SMH were homogeneous and passed through variance analyses and Tukey's test (5%) as far as fluoride concentrations and pH. Results: The results showed that pH influenced %SMH in 0.02% NaF and 0.05% NaF solutions with pH 4.0, which had less mineral loss compared to pH 7.0 (p<0.05). The 0.02% NaF - pH 4.0, and 0.05% NaF – pH 7.0 groups showed similar results (p>0.05). A dose-response relationship was observed among the tested solutions, with better anticariogenic effect for the 0.1% NaF solution. Conclusion: The results suggest that the addition of citric acid to acidulate mouth rinses reduce mineral loss. PMID:19089268

  17. Development of Potent Adenosine Monophosphate Activated Protein Kinase (AMPK) Activators.

    PubMed

    Dokla, Eman M E; Fang, Chun-Sheng; Lai, Po-Ting; Kulp, Samuel K; Serya, Rabah A T; Ismail, Nasser S M; Abouzid, Khaled A M; Chen, Ching-Shih

    2015-11-01

    Previously, we reported the identification of a thiazolidinedione-based adenosine monophosphate activated protein kinase (AMPK) activator, compound 1 (N-[4-({3-[(1-methylcyclohexyl)methyl]-2,4-dioxothiazolidin-5-ylidene}methyl)phenyl]-4-nitro-3-(trifluoromethyl)benzenesulfonamide), which provided a proof of concept to delineate the intricate role of AMPK in regulating oncogenic signaling pathways associated with cell proliferation and epithelial-mesenchymal transition (EMT) in cancer cells. In this study, we used 1 as a scaffold to conduct lead optimization, which generated a series of derivatives. Analysis of the antiproliferative and AMPK-activating activities of individual derivatives revealed a distinct structure-activity relationship and identified 59 (N-(3-nitrophenyl)-N'-{4-[(3-{[3,5-bis(trifluoromethyl)phenyl]methyl}-2,4-dioxothiazolidin-5-ylidene)methyl]phenyl}urea) as the optimal agent. Relative to 1, compound 59 exhibits multifold higher potency in upregulating AMPK phosphorylation in various cell lines irrespective of their liver kinase B1 (LKB1) functional status, accompanied by parallel changes in the phosphorylation/expression levels of p70S6K, Akt, Foxo3a, and EMT-associated markers. Consistent with its predicted activity against tumors with activated Akt status, orally administered 59 was efficacious in suppressing the growth of phosphatase and tensin homologue (PTEN)-null PC-3 xenograft tumors in nude mice. Together, these findings suggest that 59 has clinical value in therapeutic strategies for PTEN-negative cancer and warrants continued investigation in this regard.

  18. Novel Gallate Triphenylphosphonium Derivatives with Potent Antichagasic Activity.

    PubMed

    Cortes, Leonel A; Castro, Lorena; Pesce, Bárbara; Maya, Juan D; Ferreira, Jorge; Castro-Castillo, Vicente; Parra, Eduardo; Jara, José A; López-Muñoz, Rodrigo

    2015-01-01

    disease is one of the most neglected tropical diseases in the world, affecting nearly 15 million people, primarily in Latin America. Only two drugs are used for the treatment of this disease, nifurtimox and benznidazole. These drugs have limited efficacy and frequently induce adverse effects, limiting their usefulness. Consequently, new drugs must be found. In this study, we demonstrated the in vitro trypanocidal effects of a series of four gallic acid derivatives characterized by a gallate group linked to a triphenylphosphonium (TPP(+)) moiety (a delocalized cation) via a hydrocarbon chain of 8, 10, 11, or 12 atoms (TPP(+)-C8, TPP(+)-C10, TPP(+)-C11, and TPP(+)-C12, respectively). We analyzed parasite viability in isolated parasites (by MTT reduction and flow cytometry) and infected mammalian cells using T. cruzi Y strain trypomastigotes. Among the four derivatives, TPP(+)-C10 and TPP(+)-C12 were the most potent in both models, with EC50 values (in isolated parasites) of 1.0 ± 0.6 and 1.0 ± 0.7 μM, respectively, and were significantly more potent than nifurtimox (EC50 = 4.1 ± 0.6 μM). At 1 μM, TPP(+)-C10 and TPP(+)-C12 induced markers of cell death, such as phosphatidylserine exposure and propidium iodide permeabilization. In addition, at 1 μM, TPP(+)-C10 and TPP(+)-C12 significantly decreased the number of intracellular amastigotes (TPP(+)-C10: 24.3%, TPP(+)-C12: 19.0% of control measurements, as measured by DAPI staining) and the parasite's DNA load (C10: 10%, C12: 13% of control measurements, as measured by qPCR). Based on the previous mode of action described for these compounds in cancer cells, we explored their mitochondrial effects in isolated trypomastigotes. TPP(+)-C10 and TPP(+)-C12 were the most potent compounds, significantly altering mitochondrial membrane potential at 1 μM (measured by JC-1 fluorescence) and inducing mitochondrial transition pore opening at 5 μM. Taken together, these results indicate that the TPP(+)-C10 and TPP(+)-C12

  19. Novel Gallate Triphenylphosphonium Derivatives with Potent Antichagasic Activity

    PubMed Central

    Cortes, Leonel A.; Castro, Lorena; Pesce, Bárbara; Maya, Juan D.; Ferreira, Jorge; Castro-Castillo, Vicente; Parra, Eduardo; Jara, José A.; López-Muñoz, Rodrigo

    2015-01-01

    Chagas disease is one of the most neglected tropical diseases in the world, affecting nearly 15 million people, primarily in Latin America. Only two drugs are used for the treatment of this disease, nifurtimox and benznidazole. These drugs have limited efficacy and frequently induce adverse effects, limiting their usefulness. Consequently, new drugs must be found. In this study, we demonstrated the in vitro trypanocidal effects of a series of four gallic acid derivatives characterized by a gallate group linked to a triphenylphosphonium (TPP+) moiety (a delocalized cation) via a hydrocarbon chain of 8, 10, 11, or 12 atoms (TPP+-C8, TPP+-C10, TPP+-C11, and TPP+-C12, respectively). We analyzed parasite viability in isolated parasites (by MTT reduction and flow cytometry) and infected mammalian cells using T. cruzi Y strain trypomastigotes. Among the four derivatives, TPP+-C10 and TPP+-C12 were the most potent in both models, with EC50 values (in isolated parasites) of 1.0 ± 0.6 and 1.0 ± 0.7 μM, respectively, and were significantly more potent than nifurtimox (EC50 = 4.1 ± 0.6 μM). At 1 μM, TPP+-C10 and TPP+-C12 induced markers of cell death, such as phosphatidylserine exposure and propidium iodide permeabilization. In addition, at 1 μM, TPP+-C10 and TPP+-C12 significantly decreased the number of intracellular amastigotes (TPP+-C10: 24.3%, TPP+-C12: 19.0% of control measurements, as measured by DAPI staining) and the parasite’s DNA load (C10: 10%, C12: 13% of control measurements, as measured by qPCR). Based on the previous mode of action described for these compounds in cancer cells, we explored their mitochondrial effects in isolated trypomastigotes. TPP+-C10 and TPP+-C12 were the most potent compounds, significantly altering mitochondrial membrane potential at 1 μM (measured by JC-1 fluorescence) and inducing mitochondrial transition pore opening at 5 μM. Taken together, these results indicate that the TPP+-C10 and TPP+-C12 derivatives of gallic acid are

  20. Novel Gallate Triphenylphosphonium Derivatives with Potent Antichagasic Activity.

    PubMed

    Cortes, Leonel A; Castro, Lorena; Pesce, Bárbara; Maya, Juan D; Ferreira, Jorge; Castro-Castillo, Vicente; Parra, Eduardo; Jara, José A; López-Muñoz, Rodrigo

    2015-01-01

    disease is one of the most neglected tropical diseases in the world, affecting nearly 15 million people, primarily in Latin America. Only two drugs are used for the treatment of this disease, nifurtimox and benznidazole. These drugs have limited efficacy and frequently induce adverse effects, limiting their usefulness. Consequently, new drugs must be found. In this study, we demonstrated the in vitro trypanocidal effects of a series of four gallic acid derivatives characterized by a gallate group linked to a triphenylphosphonium (TPP(+)) moiety (a delocalized cation) via a hydrocarbon chain of 8, 10, 11, or 12 atoms (TPP(+)-C8, TPP(+)-C10, TPP(+)-C11, and TPP(+)-C12, respectively). We analyzed parasite viability in isolated parasites (by MTT reduction and flow cytometry) and infected mammalian cells using T. cruzi Y strain trypomastigotes. Among the four derivatives, TPP(+)-C10 and TPP(+)-C12 were the most potent in both models, with EC50 values (in isolated parasites) of 1.0 ± 0.6 and 1.0 ± 0.7 μM, respectively, and were significantly more potent than nifurtimox (EC50 = 4.1 ± 0.6 μM). At 1 μM, TPP(+)-C10 and TPP(+)-C12 induced markers of cell death, such as phosphatidylserine exposure and propidium iodide permeabilization. In addition, at 1 μM, TPP(+)-C10 and TPP(+)-C12 significantly decreased the number of intracellular amastigotes (TPP(+)-C10: 24.3%, TPP(+)-C12: 19.0% of control measurements, as measured by DAPI staining) and the parasite's DNA load (C10: 10%, C12: 13% of control measurements, as measured by qPCR). Based on the previous mode of action described for these compounds in cancer cells, we explored their mitochondrial effects in isolated trypomastigotes. TPP(+)-C10 and TPP(+)-C12 were the most potent compounds, significantly altering mitochondrial membrane potential at 1 μM (measured by JC-1 fluorescence) and inducing mitochondrial transition pore opening at 5 μM. Taken together, these results indicate that the TPP(+)-C10 and TPP(+)-C12

  1. Triazolophthalazines: Easily Accessible Compounds with Potent Antitubercular Activity.

    PubMed

    Veau, Damien; Krykun, Serhii; Mori, Giorgia; Orena, Beatrice S; Pasca, Maria R; Frongia, Céline; Lobjois, Valérie; Chassaing, Stefan; Lherbet, Christian; Baltas, Michel

    2016-05-19

    Tuberculosis (TB) remains one of the major causes of death worldwide, in particular because of the emergence of multidrug-resistant TB. Herein we explored the potential of an alternative class of molecules as anti-TB agents. Thus, a series of novel 3-substituted triazolophthalazines was quickly and easily prepared from commercial hydralazine hydrochloride as starting material and were further evaluated for their antimycobacterial activities and cytotoxicities. Four of the synthesized compounds were found to effectively inhibit the Mycobacterium tuberculosis (M.tb) H37 Rv strain with minimum inhibitory concentration (MIC) values <10 μg mL(-1) , whereas no compounds displayed cytotoxicity against HCT116 human cell lines (IC50 >100 μm). More remarkably, the most potent compounds proved to be active to a similar extent against various multidrug-resistant M.tb strains, thus uncovering a mode of action distinct from that of standard antitubercular agents. Overall, their ease of preparation, combined with their attractive antimycobacterial activities, make such triazolophthalazine-based derivatives promising leads for further development.

  2. Triazolophthalazines: Easily Accessible Compounds with Potent Antitubercular Activity.

    PubMed

    Veau, Damien; Krykun, Serhii; Mori, Giorgia; Orena, Beatrice S; Pasca, Maria R; Frongia, Céline; Lobjois, Valérie; Chassaing, Stefan; Lherbet, Christian; Baltas, Michel

    2016-05-19

    Tuberculosis (TB) remains one of the major causes of death worldwide, in particular because of the emergence of multidrug-resistant TB. Herein we explored the potential of an alternative class of molecules as anti-TB agents. Thus, a series of novel 3-substituted triazolophthalazines was quickly and easily prepared from commercial hydralazine hydrochloride as starting material and were further evaluated for their antimycobacterial activities and cytotoxicities. Four of the synthesized compounds were found to effectively inhibit the Mycobacterium tuberculosis (M.tb) H37 Rv strain with minimum inhibitory concentration (MIC) values <10 μg mL(-1) , whereas no compounds displayed cytotoxicity against HCT116 human cell lines (IC50 >100 μm). More remarkably, the most potent compounds proved to be active to a similar extent against various multidrug-resistant M.tb strains, thus uncovering a mode of action distinct from that of standard antitubercular agents. Overall, their ease of preparation, combined with their attractive antimycobacterial activities, make such triazolophthalazine-based derivatives promising leads for further development. PMID:27097919

  3. Synthetic galactomannans with potent anti-HIV activity.

    PubMed

    Budragchaa, Davaanyam; Bai, Shiming; Kanamoto, Taisei; Nakashima, Hideki; Han, Shuqin; Yoshida, Takashi

    2015-10-01

    Ring-opening polymerization of a new 1,6-anhydro disaccharide monomer, 1, 6-anhydro-2, 3-di-O-benzyl-4-O-(2', 3', 4', 6'-tetra-O-benzyl-α-d-galactopyranosyl)-α-d-mannopyranose, was carried out using PF5 as a catalyst under high vacuum at -60°C to give galactose branched mannopyranan (synthetic galactomannan), 4-O-α-d-galactopyranosyl-(1→6)-α-d-mannopyranan, after debenzylation with Na in liquid NH3. The ring-opening copolymerization with 1, 6-anhydro-tri-O-benzyl-α-d-mannopyranose in various feeds was also performed to give synthetic galactomannans with various proportions of galactose branches. After sulfation, sulfated synthetic galactomannans were found to have anti-HIV activity and cytotoxicity as high and low as those of standard curdlan and dextran sulfates, respectively, which are potent anti-HIV sulfated polysaccharides with low cytotoxicity. The anti-HIV mechanism of sulfated synthetic galactomannans used by poly-l-lysine as a model peptide of the HIV surface protein was estimated by using SPR, DSL, and zeta potential measurements, revealing the electrostatic interaction between negatively charged sulfate groups and positively charged amino groups.

  4. Cucurbitacin E Potently Modulates the Activity of Encephalitogenic Cells.

    PubMed

    Jevtić, Bojan; Djedović, Neda; Stanisavljević, Suzana; Despotović, Jovana; Miljković, Djordje; Timotijević, Gordana

    2016-06-22

    Cucurbitacin E (CucE) is a highly oxidized steroid consisting of a tetracyclic triterpene. It is a member of a Cucurbitacin family of biomolecules that are predominantly found in Cucurbitaceae plants. CucE has already been identified as a potent anti-inflammatory compound. Here, its effects on CD4(+) T helper (Th) cells and macrophages, as the major encephalitogenic cells in the autoimmunity of the central nervous system, were investigated. Production of major pathogenic Th cell cytokines: interferon-gamma and interleukin-17 were inhibited under the influence of CucE. The effects of CucE on CD4(+) T cells were mediated through the modulation of aryl hydrocarbon receptor, STAT3, NFκB, p38 MAPK, and miR-146 signaling. Further, production of nitric oxide and reactive oxygen species, as well as phagocytic ability, were inhibited in macrophages treated with CucE. These results imply that CucE possesses powerful antiencephalitogenic activity. PMID:27225664

  5. Synthetic galactomannans with potent anti-HIV activity.

    PubMed

    Budragchaa, Davaanyam; Bai, Shiming; Kanamoto, Taisei; Nakashima, Hideki; Han, Shuqin; Yoshida, Takashi

    2015-10-01

    Ring-opening polymerization of a new 1,6-anhydro disaccharide monomer, 1, 6-anhydro-2, 3-di-O-benzyl-4-O-(2', 3', 4', 6'-tetra-O-benzyl-α-d-galactopyranosyl)-α-d-mannopyranose, was carried out using PF5 as a catalyst under high vacuum at -60°C to give galactose branched mannopyranan (synthetic galactomannan), 4-O-α-d-galactopyranosyl-(1→6)-α-d-mannopyranan, after debenzylation with Na in liquid NH3. The ring-opening copolymerization with 1, 6-anhydro-tri-O-benzyl-α-d-mannopyranose in various feeds was also performed to give synthetic galactomannans with various proportions of galactose branches. After sulfation, sulfated synthetic galactomannans were found to have anti-HIV activity and cytotoxicity as high and low as those of standard curdlan and dextran sulfates, respectively, which are potent anti-HIV sulfated polysaccharides with low cytotoxicity. The anti-HIV mechanism of sulfated synthetic galactomannans used by poly-l-lysine as a model peptide of the HIV surface protein was estimated by using SPR, DSL, and zeta potential measurements, revealing the electrostatic interaction between negatively charged sulfate groups and positively charged amino groups. PMID:26076622

  6. Promoter Activation by CII, a Potent Transcriptional Activator from Bacteriophage 186*

    PubMed Central

    Murchland, Iain; Ahlgren-Berg, Alexandra; Priest, David G.; Dodd, Ian B.; Shearwin, Keith E.

    2014-01-01

    The lysogeny promoting protein CII from bacteriophage 186 is a potent transcriptional activator, capable of mediating at least a 400-fold increase in transcription over basal activity. Despite being functionally similar to its counterpart in phage λ, it shows no homology at the level of protein sequence and does not belong to any known family of transcriptional activators. It also has the unusual property of binding DNA half-sites that are separated by 20 base pairs, center to center. Here we investigate the structural and functional properties of CII using a combination of genetics, in vitro assays, and mutational analysis. We find that 186 CII possesses two functional domains, with an independent activation epitope in each. 186 CII owes its potent activity to activation mechanisms that are dependent on both the σ70 and α C-terminal domain (αCTD) components of RNA polymerase, contacting different functional domains. We also present evidence that like λ CII, 186 CII is proteolytically degraded in vivo, but unlike λ CII, 186 CII proteolysis results in a specific, transcriptionally inactive, degradation product with altered self-association properties. PMID:25294872

  7. Nuclease activity of Saccharomyces cerevisiae Dna2 inhibits its potent DNA helicase activity

    PubMed Central

    Levikova, Maryna; Klaue, Daniel; Seidel, Ralf; Cejka, Petr

    2013-01-01

    Dna2 is a nuclease-helicase involved in several key pathways of eukaryotic DNA metabolism. The potent nuclease activity of Saccharomyces cerevisiae Dna2 was reported to be required for all its in vivo functions tested to date. In contrast, its helicase activity was shown to be weak, and its inactivation affected only a subset of Dna2 functions. We describe here a complex interplay of the two enzymatic activities. We show that the nuclease of Dna2 inhibits its helicase by cleaving 5′ flaps that are required by the helicase domain for loading onto its substrate. Mutational inactivation of Dna2 nuclease unleashes unexpectedly vigorous DNA unwinding activity, comparable with that of the most potent eukaryotic helicases. Thus, the ssDNA-specific nuclease activity of Dna2 limits and controls the enzyme's capacity to unwind dsDNA. We postulate that regulation of this interplay could modulate the biochemical properties of Dna2 and thus license it to carry out its distinct cellular functions. PMID:23671118

  8. Cariostatic Effect of Green Tea in Comparison with Common Anticariogenic Agents: An in Vitro Study

    PubMed Central

    Jazaeri, Mina; Pakdek, Farzaneh; Rezaei-Soufi, Loghman; Abdolsamadi, Hamidreza; Rafieian, Nasrin

    2015-01-01

    Background and aims. Anticariogenic effects of different mouthrinses have been shown previously. In this in vitro study the anticariogenic effects of polyphenol extract of green tea with 0.05% fluoride, 0.2% chlorhexidine and fluoride-chlorhexidine were compared. Materials and methods. This in vitro study was performed on 50 maxillary premolars in 5 groups: 1) normal saline; 2) a 10% solution of green tea polyphenol extract; 3) 0.05% fluoride; 4) 0.2% chlorhexidine; and 5) fluoride-chlorhexidine. Each tooth was placed in a tube which contained a cariogenic solution. Every day the teeth were washed (depending on the experimental groups) with 5 mL of mouthrinse solution. The depth of the caries was measured under a polarized light microscope. Data were analyzed using SPSS 13.0 with Kolmogorov-Smirnov, one-way ANOVA and Tukey tests. Results. The mean and standard deviation (in µm) of caries depth were 194±16.43, 175±17.94, 142±9.34, 155±13.27, and 144±8.57 in groups 1 to 5, respectively, with significant differences between the groups (P<0.001). Tukey test showed that although there was no significant difference in the depth of caries in groups 1 and 2 (P>0.001), they were significantlyless than those in groups 3 to 5 (P<0.001). There was no significant difference between decay depth of groups 3, 4 and 5 (P>0.001). Conclusion. The anticariogenic effect of fluoride-chlorhexidine was the highest among the groups. Although green tea showed higher cariostatic effects than normal saline, in comparison with other mouthrinses, it is less effective. More re-search is strongly recommended for clinical use of green tea as an anticariogenic agent. PMID:25973154

  9. Cariostatic effect of green tea in comparison with common anticariogenic agents: an in vitro study.

    PubMed

    Jazaeri, Mina; Pakdek, Farzaneh; Rezaei-Soufi, Loghman; Abdolsamadi, Hamidreza; Rafieian, Nasrin

    2015-01-01

    Background and aims. Anticariogenic effects of different mouthrinses have been shown previously. In this in vitro study the anticariogenic effects of polyphenol extract of green tea with 0.05% fluoride, 0.2% chlorhexidine and fluoride-chlorhexidine were compared. Materials and methods. This in vitro study was performed on 50 maxillary premolars in 5 groups: 1) normal saline; 2) a 10% solution of green tea polyphenol extract; 3) 0.05% fluoride; 4) 0.2% chlorhexidine; and 5) fluoride-chlorhexidine. Each tooth was placed in a tube which contained a cariogenic solution. Every day the teeth were washed (depending on the experimental groups) with 5 mL of mouthrinse solution. The depth of the caries was measured under a polarized light microscope. Data were analyzed using SPSS 13.0 with Kolmogorov-Smirnov, one-way ANOVA and Tukey tests. Results. The mean and standard deviation (in µm) of caries depth were 194±16.43, 175±17.94, 142±9.34, 155±13.27, and 144±8.57 in groups 1 to 5, respectively, with significant differences between the groups (P<0.001). Tukey test showed that although there was no significant difference in the depth of caries in groups 1 and 2 (P>0.001), they were significantlyless than those in groups 3 to 5 (P<0.001). There was no significant difference between decay depth of groups 3, 4 and 5 (P>0.001). Conclusion. The anticariogenic effect of fluoride-chlorhexidine was the highest among the groups. Although green tea showed higher cariostatic effects than normal saline, in comparison with other mouthrinses, it is less effective. More re-search is strongly recommended for clinical use of green tea as an anticariogenic agent. PMID:25973154

  10. Novel Mps1 Kinase Inhibitors with Potent Antitumor Activity.

    PubMed

    Wengner, Antje M; Siemeister, Gerhard; Koppitz, Marcus; Schulze, Volker; Kosemund, Dirk; Klar, Ulrich; Stoeckigt, Detlef; Neuhaus, Roland; Lienau, Philip; Bader, Benjamin; Prechtl, Stefan; Raschke, Marian; Frisk, Anna-Lena; von Ahsen, Oliver; Michels, Martin; Kreft, Bertolt; von Nussbaum, Franz; Brands, Michael; Mumberg, Dominik; Ziegelbauer, Karl

    2016-04-01

    Monopolar spindle 1 (Mps1) has been shown to function as the key kinase that activates the spindle assembly checkpoint (SAC) to secure proper distribution of chromosomes to daughter cells. Here, we report the structure and functional characterization of two novel selective Mps1 inhibitors, BAY 1161909 and BAY 1217389, derived from structurally distinct chemical classes. BAY 1161909 and BAY 1217389 inhibited Mps1 kinase activity with IC50 values below 10 nmol/L while showing an excellent selectivity profile. In cellular mechanistic assays, both Mps1 inhibitors abrogated nocodazole-induced SAC activity and induced premature exit from mitosis ("mitotic breakthrough"), resulting in multinuclearity and tumor cell death. Both compounds efficiently inhibited tumor cell proliferation in vitro (IC50 nmol/L range). In vivo, BAY 1161909 and BAY 1217389 achieved moderate efficacy in monotherapy in tumor xenograft studies. However, in line with its unique mode of action, when combined with paclitaxel, low doses of Mps1 inhibitor reduced paclitaxel-induced mitotic arrest by the weakening of SAC activity. As a result, combination therapy strongly improved efficacy over paclitaxel or Mps1 inhibitor monotreatment at the respective MTDs in a broad range of xenograft models, including those showing acquired or intrinsic paclitaxel resistance. Both Mps1 inhibitors showed good tolerability without adding toxicity to paclitaxel monotherapy. These preclinical findings validate the innovative concept of SAC abrogation for cancer therapy and justify clinical proof-of-concept studies evaluating the Mps1 inhibitors BAY 1161909 and BAY 1217389 in combination with antimitotic cancer drugs to enhance their efficacy and potentially overcome resistance. Mol Cancer Ther; 15(4); 583-92. ©2016 AACR.

  11. Synthesis and structure-activity relationships of potent 4-fluoro-2-cyanopyrrolidine dipeptidyl peptidase IV inhibitors.

    PubMed

    Fukushima, Hiroshi; Hiratate, Akira; Takahashi, Masato; Mikami, Ayako; Saito-Hori, Masako; Munetomo, Eiji; Kitano, Kiyokazu; Chonan, Sumi; Saito, Hidetaka; Suzuki, Akio; Takaoka, Yuji; Yamamoto, Koji

    2008-04-01

    Dipeptidyl peptidase IV (DPP-IV) inhibitors are promising antidiabetic drugs, and several drugs are in the developmental stage. We previously reported that the introduction of fluorine to the 4-position of 2-cyanopyrrolidine enhanced the DPP-IV inhibitory effect. In the present report, we examined the structure-activity relationship (SAR) of 2-cyano-4-fluoropyrrolidine with N-substituted glycine at the 1-position. We report the identification of a potent and stable DPP-IV inhibitor (TS-021) with a long-term persistent plasma drug concentration and a potent antihyperglycemic activity.

  12. Nobiletin: a citrus flavonoid displaying potent physiological activity.

    PubMed

    Noguchi, Shuji; Atsumi, Haruka; Iwao, Yasunori; Kan, Toshiyuki; Itai, Shigeru

    2016-02-01

    Nobiletin [systematic name: 2-(3,4-dimethoxyphenyl)-5,6,7,8-tetramethoxy-4H-chromen-4-one; C21H22O8] is a flavonoid found in citrus peels, and has been reported to show a wide range of physiological properties, including anti-inflammatory, anticancer and antidementia activities. We have solved the crystal structure of nobiletin, which revealed that the chromene and arene rings of its flavone moiety, as well as the two methoxy groups bound to its arene ring, were coplanar. In contrast, the C atoms of the four methoxy groups bound to the chromene ring are out of the plane, making the molecule conformationally chiral. A comparison of the crystal structures of nobiletin revealed that it could adopt a variety of different conformations through rotation of the covalent bond between the chromene and arene rings, and the orientations of methoxy groups bound to the chromene ring.

  13. The sGC activator BAY 60-2770 has potent erectile activity in the rat.

    PubMed

    Lasker, George F; Pankey, Edward A; Frink, Terrence J; Zeitzer, Jonathan R; Walter, Korey A; Kadowitz, Philip J

    2013-06-15

    Nitric oxide (NO) is the principal mediator of penile erection, and soluble guanylate cyclase (sGC) is the receptor for NO. In pathophysiological conditions when sGC is inactivated and not responsive to NO or sGC stimulators a new class of agents called sGC activators increase the activity of NO-insensitive sGC and produce erection. The aim of this study was to investigate erectile responses to BAY 60-2770, a sGC activator, under physiological and pathophysiological conditions. In the present study increases in intracavernosal pressure (ICP) in response to intracavernosal (ic) injections of BAY 60-2770 were investigated under baseline conditions, when sGC was inhibited by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), when nitric oxide synthase (NOS) was inhibited by N-nitro-L-arginine methyl ester (L-NAME), and after cavernosal nerve crush injury. Under baseline conditions ic injections of BAY 60-2770 increase ICP, ICP/mean arterial pressure (MAP), and area under the ICP curve (AUC) and produce small decreases in MAP at the highest doses studied. BAY 60-2770 was very potent in its ability to induce erection and responses to BAY 60-2770 were enhanced by ODQ which attenuates erectile responses to sodium nitroprusside (SNP), diethylamine NONOate (DEA/NO), and cavernosal nerve stimulation. Responses to BAY 60-2770 were not altered by L-NAME or cavernosal nerve crush injury. These data indicate that BAY 60-2770 has potent erectile activity that is enhanced by ODQ and show that responses to BAY 60-2770 are not attenuated by NOS inhibition or cavernosal nerve injury. These results suggest that BAY 60-2770 would be effective in the treatment of erectile dysfunction when NO bioavailability is reduced, after pelvic nerve injury, and when sGC is oxidized.

  14. Potent cough suppression by physiologically active substance in human plasma.

    PubMed

    Akaike, Norio; Ito, Yushi; Ogawa, Sachie K; Maeda, Megumi; Wakita, Masahito; Takahama, Kazuo; Noguchi, Tetsuro; Kamei, Shintaro; Hamamoto, Takayoshi; Umehashi, Misako; Maeda, Hiroaki

    2014-01-01

    Human plasma contains wide variety of bioactive proteins that have proved essential in therapeutic discovery. However many human plasma proteins remain orphans with unknown biological functions. Evidences suggest that some plasma components target the respiratory system. In the present study we adapted heparin affinity chromatography to fractionate human plasma for functional bioassay. Fractions from pooled human plasma yielded particular plasma fractions with strong cough suppressing effects. Purification yielded a fraction that was finally identified as an activated blood coagulation factor fXIa using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and matrix-assisted laser desorption ionization/time-of-flight mass spectrometry (MALDI/TOF-MS). The fraction almost completely suppressed coughs induced by either chemical or mechanical stimulation applied to larynx or bifurcation of guinea-pig trachea. Cough suppressing effect of the fraction and commercially available fXIa were one million times stronger than codeine and codeine only partially suppressed the mechanically triggered coughing in animal model. Recent reviews highlighted prominent shortcomings of current available antitussives, including narcotic opioids such as codeine and their unpleasant or intolerable side effects. Therefore, safer and more effective cough suppressants would be welcome, and present findings indicate that fXIa in human plasma as a very promising, new therapeutic candidate for effective antitussive action.

  15. Cerecidins, novel lantibiotics from Bacillus cereus with potent antimicrobial activity.

    PubMed

    Wang, Jian; Zhang, Li; Teng, Kunling; Sun, Shutao; Sun, Zhizeng; Zhong, Jin

    2014-04-01

    Lantibiotics are ribosomally synthesized and posttranslationally modified antimicrobial peptides that are widely produced by Gram-positive bacteria, including many species of the Bacillus group. In the present study, one novel gene cluster coding lantibiotic cerecidins was unveiled in Bacillus cereus strain As 1.1846 through genomic mining and PCR screening. The designated cer locus is different from that of conventional class II lantibiotics in that it included seven tandem precursor cerA genes, one modification gene (cerM), two processing genes (cerT and cerP), one orphan regulator gene (cerR), and two immunity genes (cerF and cerE). In addition, one unprecedented quorum sensing component, comQXPA, was inserted between cerM and cerR. The expression of cerecidins was not detected in this strain of B. cereus, which might be due to repressed transcription of cerM. We constitutively coexpressed cerA genes and cerM in Escherichia coli, and purified precerecidins were proteolytically processed with the endoproteinase GluC and a truncated version of putative serine protease CerP. Thus, two natural variants of cerecidins A1 and A7 were obtained which contained two terminal nonoverlapping thioether rings rarely found in lantibiotics. Both cerecidins A1 and A7 were active against a broad spectrum of Gram-positive bacteria. Cerecidin A7, especially its mutant Dhb13A, showed remarkable efficacy against multidrug-resistant Staphylococcus aureus (MDRSA), vancomycin-resistant Enterococcus faecalis (VRE), and even Streptomyces.

  16. Cerecidins, Novel Lantibiotics from Bacillus cereus with Potent Antimicrobial Activity

    PubMed Central

    Wang, Jian; Zhang, Li; Teng, Kunling; Sun, Shutao; Sun, Zhizeng

    2014-01-01

    Lantibiotics are ribosomally synthesized and posttranslationally modified antimicrobial peptides that are widely produced by Gram-positive bacteria, including many species of the Bacillus group. In the present study, one novel gene cluster coding lantibiotic cerecidins was unveiled in Bacillus cereus strain As 1.1846 through genomic mining and PCR screening. The designated cer locus is different from that of conventional class II lantibiotics in that it included seven tandem precursor cerA genes, one modification gene (cerM), two processing genes (cerT and cerP), one orphan regulator gene (cerR), and two immunity genes (cerF and cerE). In addition, one unprecedented quorum sensing component, comQXPA, was inserted between cerM and cerR. The expression of cerecidins was not detected in this strain of B. cereus, which might be due to repressed transcription of cerM. We constitutively coexpressed cerA genes and cerM in Escherichia coli, and purified precerecidins were proteolytically processed with the endoproteinase GluC and a truncated version of putative serine protease CerP. Thus, two natural variants of cerecidins A1 and A7 were obtained which contained two terminal nonoverlapping thioether rings rarely found in lantibiotics. Both cerecidins A1 and A7 were active against a broad spectrum of Gram-positive bacteria. Cerecidin A7, especially its mutant Dhb13A, showed remarkable efficacy against multidrug-resistant Staphylococcus aureus (MDRSA), vancomycin-resistant Enterococcus faecalis (VRE), and even Streptomyces. PMID:24532070

  17. Latrepirdine is a potent activator of AMP-activated protein kinase and reduces neuronal excitability

    PubMed Central

    Weisová, P; Alvarez, S P; Kilbride, S M; Anilkumar, U; Baumann, B; Jordán, J; Bernas, T; Huber, H J; Düssmann, H; Prehn, J H M

    2013-01-01

    Latrepirdine/Dimebon is a small-molecule compound with attributed neurocognitive-enhancing activities, which has recently been tested in clinical trials for the treatment of Alzheimer's and Huntington's disease. Latrepirdine has been suggested to be a neuroprotective agent that increases mitochondrial function, however the molecular mechanisms underlying these activities have remained elusive. We here demonstrate that latrepirdine, at (sub)nanomolar concentrations (0.1 nM), activates the energy sensor AMP-activated protein kinase (AMPK). Treatment of primary neurons with latrepirdine increased intracellular ATP levels and glucose transporter 3 translocation to the plasma membrane. Latrepirdine also increased mitochondrial uptake of the voltage-sensitive probe TMRM. Gene silencing of AMPKα or its upstream kinases, LKB1 and CaMKKβ, inhibited this effect. However, studies using the plasma membrane potential indicator DisBAC2(3) demonstrated that the effects of latrepirdine on TMRM uptake were largely mediated by plasma membrane hyperpolarization, precluding a purely ‘mitochondrial' mechanism of action. In line with a stabilizing effect of latrepirdine on plasma membrane potential, pretreatment with latrepirdine reduced spontaneous Ca2+ oscillations as well as glutamate-induced Ca2+ increases in primary neurons, and protected neurons against glutamate toxicity. In conclusion, our experiments demonstrate that latrepirdine is a potent activator of AMPK, and suggest that one of the main pharmacological activities of latrepirdine is a reduction in neuronal excitability. PMID:24150226

  18. Potent complement C3a receptor agonists derived from oxazole amino acids: Structure-activity relationships.

    PubMed

    Singh, Ranee; Reed, Anthony N; Chu, Peifei; Scully, Conor C G; Yau, Mei-Kwan; Suen, Jacky Y; Durek, Thomas; Reid, Robert C; Fairlie, David P

    2015-12-01

    Potent ligands for the human complement C3a receptor (C3aR) were developed from the almost inactive tripeptide Leu-Ala-Arg corresponding to the three C-terminal residues of the endogenous peptide agonist C3a. The analogous Leu-Ser-Arg was modified by condensing the serine side chain with the leucine carbonyl with elimination of water to form leucine-oxazole-arginine. Subsequent elaboration with a variety of N-terminal amide capping groups produced agonists as potent as human C3a itself in stimulating Ca(2+) release from human macrophages. Structure-activity relationships are discussed.

  19. Tear gasses CN, CR, and CS are potent activators of the human TRPA1 receptor

    SciTech Connect

    Brone, Bert; Peeters, Pieter J.; Marrannes, Roger; Mercken, Marc; Nuydens, Ronny; Meert, Theo; Gijsen, Harrie J.M.

    2008-09-01

    The TRPA1 channel is activated by a number of pungent chemicals, such as allylisothiocyanate, present in mustard oil and thiosulfinates present in garlic. Most of the known activating compounds contain reactive, electrophilic chemical groups, reacting with cysteine residues in the active site of the TRPA1 channel. This covalent modification results in activation of the channel and has been shown to be reversible for several ligands. Commonly used tear gasses CN, CR and CS are also pungent chemicals, and in this study we show that they are extremely potent and selective activators of the human TRPA1 receptor. To our knowledge, these are the most potent TRPA1 agonists known to date. The identification of the molecular target for these tear gasses may open up possibilities to alleviate the effects of tear gasses via treatment with TRPA1 antagonists. In addition these results may contribute to the basic knowledge of the TRPA1 channel that is gaining importance as a pharmacological target.

  20. Quinazolinone and quinazoline derivatives: recent structures with potent antimicrobial and cytotoxic activities

    PubMed Central

    Jafari, Elham; Khajouei, Marzieh Rahmani; Hassanzadeh, Farshid; Hakimelahi, Gholam Hossein; Khodarahmi, Ghadam Ali

    2016-01-01

    The heterocyclic compounds have a great importance in medicinal chemistry. One of the most important heterocycles in medicinal chemistry are quinazolines possessing wide spectrum of biological properties like antibacterial, antifungal, anticonvulsant, anti-inflammatory, anti-HIV, anticancer and analgesic activities. This skeleton is an important pharmacophore considered as a privileged structure. This review highlights the recent advances in the synthesis of quinazolines and quinazolinone derivatives with potent antimicrobial and cytotoxic activities. PMID:27051427

  1. Pharmacological selectivity of the cloned human P2U-purinoceptor: potent activation by diadenosine tetraphosphate.

    PubMed Central

    Lazarowski, E. R.; Watt, W. C.; Stutts, M. J.; Boucher, R. C.; Harden, T. K.

    1995-01-01

    1. The human P2U-purinoceptor was stably expressed in 1321N1 human astrocytoma cells and the pharmacological selectivity of the expressed receptor was studied by measurement of inositol lipid hydrolysis. 2. High basal levels of inositol phosphates occurred in P2U-purinoceptor-expressing cells. This phenomenon was shown to be due to release of large amounts of ATP from 1321N1 cells, and could be circumvented by adoption of an assay protocol that did not involve medium changes. 3. UTP, ATP and ATP gamma S were full and potent agonists for activation of phospholipase C with EC50 values of 140 nM, 230 nM, and 1.72 microM, respectively. 5BrUTP, 2C1ATP and 8BrATP were also full agonists although less potent than their natural congeners. Little or no effect was observed with the selective P2Y-, P2X-, and P2T-purinoceptor agonists, 2MeSATP, alpha,beta-MeATP, and 2MeSADP, respectively. 4. Diadenosine tetraphosphate, Ap4A, was a surprisingly potent agonist at the expressed P2U-purinoceptor with an EC50 (720 nM) in the range of the most potent P2U-purinoceptor agonists. Ap4A may be a physiologically important activator of P2U-purinoceptors. PMID:8564228

  2. Cytotoxic activities of selected medicinal plants from Iran and phytochemical evaluation of the most potent extract

    PubMed Central

    Sahranavard, S.; Naghibi, F.; Mosaddegh, M.; Esmaeili, S.; Sarkhail, P.; Taghvaei, M.; Ghafari, S.

    2009-01-01

    Methanolic extract of 15 Iranian medicinal plants were prepared and tested for their cytotoxic activities against three cancer cell lines (MCF7, HepG2, WEHI164) and one normal cell line (MDBK). Some plants showed cytotoxic activities. The extract of Ferula szowitsiana root, which proved to be the most active, was chosen for further phytochemical studies. The major compounds of the most potent acetone extract were isolated. They were identified as chimgin and chimganin, two known monoterpenoids, by spectroscopic means. Their cytotoxic activity was evaluated in three cell lines. The results show that these compounds are responsible, at least in part, for the cytotoxic activity of this plant. PMID:21589808

  3. Vacuolin-1 potently and reversibly inhibits autophagosome-lysosome fusion by activating RAB5A

    PubMed Central

    Lu, Yingying; Dong, Shichen; Hao, Baixia; Li, Chang; Zhu, Kaiyuan; Guo, Wenjing; Wang, Qian; Cheung, King-Ho; Wong, Connie WM; Wu, Wu-Tian; Markus, Huss; Yue, Jianbo

    2014-01-01

    Autophagy is a catabolic lysosomal degradation process essential for cellular homeostasis and cell survival. Dysfunctional autophagy has been associated with a wide range of human diseases, e.g., cancer and neurodegenerative diseases. A large number of small molecules that modulate autophagy have been widely used to dissect this process and some of them, e.g., chloroquine (CQ), might be ultimately applied to treat a variety of autophagy-associated human diseases. Here we found that vacuolin-1 potently and reversibly inhibited the fusion between autophagosomes and lysosomes in mammalian cells, thereby inducing the accumulation of autophagosomes. Interestingly, vacuolin-1 was less toxic but at least 10-fold more potent in inhibiting autophagy compared with CQ. Vacuolin-1 treatment also blocked the fusion between endosomes and lysosomes, resulting in a defect in general endosomal-lysosomal degradation. Treatment of cells with vacuolin-1 alkalinized lysosomal pH and decreased lysosomal Ca2+ content. Besides marginally inhibiting vacuolar ATPase activity, vacuolin-1 treatment markedly activated RAB5A GTPase activity. Expression of a dominant negative mutant of RAB5A or RAB5A knockdown significantly inhibited vacuolin-1-induced autophagosome-lysosome fusion blockage, whereas expression of a constitutive active form of RAB5A suppressed autophagosome-lysosome fusion. These data suggest that vacuolin-1 activates RAB5A to block autophagosome-lysosome fusion. Vacuolin-1 and its analogs present a novel class of drug that can potently and reversibly modulate autophagy. PMID:25483964

  4. Physicochemically and pharmacokinetically stable nonapeptide KISS1 receptor agonists with highly potent testosterone-suppressive activity.

    PubMed

    Asami, Taiji; Nishizawa, Naoki; Matsui, Hisanori; Takatsu, Yoshihiro; Suzuki, Atsuko; Kiba, Atsushi; Terada, Michiko; Nishibori, Kimiko; Nakayama, Masaharu; Ban, Junko; Matsumoto, Shin-ichi; Tarui, Naoki; Ikeda, Yukihiro; Yamaguchi, Masashi; Kusaka, Masami; Ohtaki, Tetsuya; Kitada, Chieko

    2014-07-24

    Modifications of metastin(45-54) produced peptide analogues with higher metabolic stability than metastin(45-54). N-terminally truncated nonapeptide 4 ([D-Tyr46,D-Pya(4)47,azaGly51,Arg(Me)53]metastin(46-54)) is a representative compound with both potent agonistic activity and metabolic stability. Although 4 had more potent testosterone-suppressant activity than metastin, it possessed physicochemical instability at pH 7 and insufficient in vivo activity. Instability at pH 7 was dependent upon Asn48 and Ser49; substitution of Ser49 with Thr49 reduced this instability and maintained KISS1 receptor agonistic activity. Furthermore, [D-Tyr46,D-Trp47,Thr49,azaGly51,Arg(Me)53,Trp54]metastin(46-54) (14) showed 2-fold greater [Ca2+]i-mobilizing activity than metastin(45-54) and an apparent increase in physicochemical stability. N-terminal acetylation of 14 resulted in the most potent analogue, 22 (Ac-[D-Tyr46,D-Trp47,Thr49,azaGly51,Arg(Me)53,Trp54]metastin(46-54)). With continuous administration, 22 possessed 10-50-fold more potent testosterone-suppressive activity in rats than 4. These results suggested that a controlled release of short-length KISS1 receptor agonists can suppress the hypothalamic-pituitary-gonadal axis and reduce testosterone levels. Compound 22 was selected for further preclinical evaluation for hormone-dependent diseases.

  5. Novel Amino-pyrazole Ureas with Potent In Vitro and In Vivo Antileishmanial Activity.

    PubMed

    Mowbray, Charles E; Braillard, Stéphanie; Speed, William; Glossop, Paul A; Whitlock, Gavin A; Gibson, Karl R; Mills, James E J; Brown, Alan D; Gardner, J Mark F; Cao, Yafeng; Hua, Wen; Morgans, Garreth L; Feijens, Pim-Bart; Matheeussen, An; Maes, Louis J

    2015-12-24

    Visceral leishmaniasis is a severe parasitic disease that is one of the most neglected tropical diseases. Treatment options are limited, and there is an urgent need for new therapeutic agents. Following an HTS campaign and hit optimization, a novel series of amino-pyrazole ureas has been identified with potent in vitro antileishmanial activity. Furthermore, compound 26 shows high levels of in vivo efficacy (>90%) against Leishmania infantum, thus demonstrating proof of concept for this series. PMID:26571076

  6. Discovery of potent heterodimeric antagonists of inhibitor of apoptosis proteins (IAPs) with sustained antitumor activity.

    PubMed

    Perez, Heidi L; Chaudhry, Charu; Emanuel, Stuart L; Fanslau, Caroline; Fargnoli, Joseph; Gan, Jinping; Kim, Kyoung S; Lei, Ming; Naglich, Joseph G; Traeger, Sarah C; Vuppugalla, Ragini; Wei, Donna D; Vite, Gregory D; Talbott, Randy L; Borzilleri, Robert M

    2015-02-12

    The prominent role of IAPs in controlling cell death and their overexpression in a variety of cancers has prompted the development of IAP antagonists as potential antitumor therapies. We describe the identification of a series of heterodimeric antagonists with highly potent antiproliferative activities in cIAP- and XIAP-dependent cell lines. Compounds 15 and 17 further demonstrate curative efficacy in human melanoma and lung cancer xenograft models and are promising candidates for advanced studies.

  7. Pyridinium derivatives of histamine are potent activators of cytosolic carbonic anhydrase isoforms I, II and VII.

    PubMed

    Dave, Khyati; Scozzafava, Andrea; Vullo, Daniela; Supuran, Claudiu T; Ilies, Marc A

    2011-04-21

    A series of positively-charged derivatives has been prepared by reaction of histamine with substituted pyrylium salts. These pyridinium histamine derivatives were investigated as activators of the zinc enzyme carbonic anhydrase (CA, EC 4.2.1.1) and more precisely the human isoforms hCA I, II and VII. Activities from the subnanomolar to the micromolar range were detected for these compounds as activators of the three isoforms, confirming the validity of current and previous designs. The substitution pattern at the pyridinium ring was the main factor influencing activity, the three isoforms showing different structural requirements for good activity, related with the number of pyridinium substituting groups and their nature, among various alkyl, phenyl and para-substituted styryl moieties. We were successful in identifying nanomolar potent and selective activators for each isozyme and also activators with a relatively good activity against all isozymes tested--valuable lead compounds for physiology and pathology studies involving these isozymes.

  8. SAR-Based Optimization of a 4-Quinoline Carboxylic Acid Analogue with Potent Antiviral Activity

    PubMed Central

    2013-01-01

    It is established that drugs targeting viral proteins are at risk of generating resistant strains. However, drugs targeting host factors can potentially avoid this problem. Herein, we report structure–activity relationship studies leading to the discovery of a very potent lead compound 6-fluoro-2-(5-isopropyl-2-methyl-4-phenoxyphenyl)quinoline-4-carboxylic acid (C44) that inhibits human dihydroorotate dehydrogenase (DHODH) with an IC50 of 1 nM and viral replication of VSV and WSN-Influenza with an EC50 of 2 nM and 41 nM. We also solved the X-ray structure of human DHODH bound to C44, providing structural insight into the potent inhibition of biaryl ether analogues of brequinar. PMID:23930152

  9. Identification of Potent, Selective, Cell-Active Inhibitors of the Histone Lysine Methyltransferase EZH2.

    PubMed

    Verma, Sharad K; Tian, Xinrong; LaFrance, Louis V; Duquenne, Céline; Suarez, Dominic P; Newlander, Kenneth A; Romeril, Stuart P; Burgess, Joelle L; Grant, Seth W; Brackley, James A; Graves, Alan P; Scherzer, Daryl A; Shu, Art; Thompson, Christine; Ott, Heidi M; Aller, Glenn S Van; Machutta, Carl A; Diaz, Elsie; Jiang, Yong; Johnson, Neil W; Knight, Steven D; Kruger, Ryan G; McCabe, Michael T; Dhanak, Dashyant; Tummino, Peter J; Creasy, Caretha L; Miller, William H

    2012-12-13

    The histone H3-lysine 27 (H3K27) methyltransferase EZH2 plays a critical role in regulating gene expression, and its aberrant activity is linked to the onset and progression of cancer. As part of a drug discovery program targeting EZH2, we have identified highly potent, selective, SAM-competitive, and cell-active EZH2 inhibitors, including GSK926 (3) and GSK343 (6). These compounds are small molecule chemical tools that would be useful to further explore the biology of EZH2. PMID:24900432

  10. Dectin-1-activated dendritic cells trigger potent antitumour immunity through the induction of Th9 cells

    PubMed Central

    Zhao, Yinghua; Chu, Xiao; Chen, Jintong; Wang, Ying; Gao, Sujun; Jiang, Yuxue; Zhu, Xiaoqing; Tan, Guangyun; Zhao, Wenjie; Yi, Huanfa; Xu, Honglin; Ma, Xingzhe; Lu, Yong; Yi, Qing; Wang, Siqing

    2016-01-01

    Dectin-1 signalling in dendritic cells (DCs) has an important role in triggering protective antifungal Th17 responses. However, whether dectin-1 directs DCs to prime antitumour Th9 cells remains unclear. Here, we show that DCs activated by dectin-1 agonists potently promote naive CD4+ T cells to differentiate into Th9 cells. Abrogation of dectin-1 in DCs completely abolishes their Th9-polarizing capability in response to dectin-1 agonist curdlan. Notably, dectin-1 stimulation of DCs upregulates TNFSF15 and OX40L, which are essential for dectin-1-activated DC-induced Th9 cell priming. Mechanistically, dectin-1 activates Syk, Raf1 and NF-κB signalling pathways, resulting in increased p50 and RelB nuclear translocation and TNFSF15 and OX40L expression. Furthermore, immunization of tumour-bearing mice with dectin-1-activated DCs induces potent antitumour response that depends on Th9 cells and IL-9 induced by dectin-1-activated DCs in vivo. Our results identify dectin-1-activated DCs as a powerful inducer of Th9 cells and antitumour immunity and may have important clinical implications. PMID:27492902

  11. UV-inactivated HSV-1 potently activates NK cell killing of leukemic cells

    PubMed Central

    Samudio, Ismael; Rezvani, Katayoun; Shaim, Hila; Hofs, Elyse; Ngom, Mor; Bu, Luke; Liu, Guoyu; Lee, Jason T. C.; Imren, Suzan; Lam, Vivian; Poon, Grace F. T.; Ghaedi, Maryam; Takei, Fumio; Humphries, Keith; Jia, William

    2016-01-01

    Herein we demonstrate that oncolytic herpes simplex virus-1 (HSV-1) potently activates human peripheral blood mononuclear cells (PBMCs) to lyse leukemic cell lines and primary acute myeloid leukemia samples, but not healthy allogeneic lymphocytes. Intriguingly, we found that UV light–inactivated HSV-1 (UV-HSV-1) is equally effective in promoting PBMC cytolysis of leukemic cells and is 1000- to 10 000-fold more potent at stimulating innate antileukemic responses than UV-inactivated cytomegalovirus, vesicular stomatitis virus, reovirus, or adenovirus. Mechanistically, UV-HSV-1 stimulates PBMC cytolysis of leukemic cells, partly via Toll-like receptor-2/protein kinase C/nuclear factor-κB signaling, and potently stimulates expression of CD69, degranulation, migration, and cytokine production in natural killer (NK) cells, suggesting that surface components of UV-HSV-1 directly activate NK cells. Importantly, UV-HSV-1 synergizes with interleukin-15 (IL-15) and IL-2 in inducing activation and cytolytic activity of NK cells. Additionally, UV-HSV-1 stimulates glycolysis and fatty acid oxidation–dependent oxygen consumption in NK cells, but only glycolysis is required for their enhanced antileukemic activity. Last, we demonstrate that T cell–depleted human PBMCs exposed to UV-HSV-1 provide a survival benefit in a murine xenograft model of human acute myeloid leukemia (AML). Taken together, our results support the preclinical development of UV-HSV-1 as an adjuvant, alone or in combination with IL-15, for allogeneic donor mononuclear cell infusions to treat AML. PMID:26941401

  12. UV-inactivated HSV-1 potently activates NK cell killing of leukemic cells.

    PubMed

    Samudio, Ismael; Rezvani, Katayoun; Shaim, Hila; Hofs, Elyse; Ngom, Mor; Bu, Luke; Liu, Guoyu; Lee, Jason T C; Imren, Suzan; Lam, Vivian; Poon, Grace F T; Ghaedi, Maryam; Takei, Fumio; Humphries, Keith; Jia, William; Krystal, Gerald

    2016-05-26

    Herein we demonstrate that oncolytic herpes simplex virus-1 (HSV-1) potently activates human peripheral blood mononuclear cells (PBMCs) to lyse leukemic cell lines and primary acute myeloid leukemia samples, but not healthy allogeneic lymphocytes. Intriguingly, we found that UV light-inactivated HSV-1 (UV-HSV-1) is equally effective in promoting PBMC cytolysis of leukemic cells and is 1000- to 10 000-fold more potent at stimulating innate antileukemic responses than UV-inactivated cytomegalovirus, vesicular stomatitis virus, reovirus, or adenovirus. Mechanistically, UV-HSV-1 stimulates PBMC cytolysis of leukemic cells, partly via Toll-like receptor-2/protein kinase C/nuclear factor-κB signaling, and potently stimulates expression of CD69, degranulation, migration, and cytokine production in natural killer (NK) cells, suggesting that surface components of UV-HSV-1 directly activate NK cells. Importantly, UV-HSV-1 synergizes with interleukin-15 (IL-15) and IL-2 in inducing activation and cytolytic activity of NK cells. Additionally, UV-HSV-1 stimulates glycolysis and fatty acid oxidation-dependent oxygen consumption in NK cells, but only glycolysis is required for their enhanced antileukemic activity. Last, we demonstrate that T cell-depleted human PBMCs exposed to UV-HSV-1 provide a survival benefit in a murine xenograft model of human acute myeloid leukemia (AML). Taken together, our results support the preclinical development of UV-HSV-1 as an adjuvant, alone or in combination with IL-15, for allogeneic donor mononuclear cell infusions to treat AML.

  13. UV-inactivated HSV-1 potently activates NK cell killing of leukemic cells.

    PubMed

    Samudio, Ismael; Rezvani, Katayoun; Shaim, Hila; Hofs, Elyse; Ngom, Mor; Bu, Luke; Liu, Guoyu; Lee, Jason T C; Imren, Suzan; Lam, Vivian; Poon, Grace F T; Ghaedi, Maryam; Takei, Fumio; Humphries, Keith; Jia, William; Krystal, Gerald

    2016-05-26

    Herein we demonstrate that oncolytic herpes simplex virus-1 (HSV-1) potently activates human peripheral blood mononuclear cells (PBMCs) to lyse leukemic cell lines and primary acute myeloid leukemia samples, but not healthy allogeneic lymphocytes. Intriguingly, we found that UV light-inactivated HSV-1 (UV-HSV-1) is equally effective in promoting PBMC cytolysis of leukemic cells and is 1000- to 10 000-fold more potent at stimulating innate antileukemic responses than UV-inactivated cytomegalovirus, vesicular stomatitis virus, reovirus, or adenovirus. Mechanistically, UV-HSV-1 stimulates PBMC cytolysis of leukemic cells, partly via Toll-like receptor-2/protein kinase C/nuclear factor-κB signaling, and potently stimulates expression of CD69, degranulation, migration, and cytokine production in natural killer (NK) cells, suggesting that surface components of UV-HSV-1 directly activate NK cells. Importantly, UV-HSV-1 synergizes with interleukin-15 (IL-15) and IL-2 in inducing activation and cytolytic activity of NK cells. Additionally, UV-HSV-1 stimulates glycolysis and fatty acid oxidation-dependent oxygen consumption in NK cells, but only glycolysis is required for their enhanced antileukemic activity. Last, we demonstrate that T cell-depleted human PBMCs exposed to UV-HSV-1 provide a survival benefit in a murine xenograft model of human acute myeloid leukemia (AML). Taken together, our results support the preclinical development of UV-HSV-1 as an adjuvant, alone or in combination with IL-15, for allogeneic donor mononuclear cell infusions to treat AML. PMID:26941401

  14. Pyrazolo Derivatives as Potent Adenosine Receptor Antagonists: An Overview on the Structure-Activity Relationships

    PubMed Central

    Cheong, Siew Lee; Venkatesan, Gopalakrishnan; Paira, Priyankar; Jothibasu, Ramasamy; Mandel, Alexander Laurence; Federico, Stephanie; Spalluto, Giampiero; Pastorin, Giorgia

    2011-01-01

    In the past few decades, medicinal chemistry research towards potent and selective antagonists of human adenosine receptors (namely, A1, A2A, A2B, and A3) has been evolving rapidly. These antagonists are deemed therapeutically beneficial in several pathological conditions including neurological and renal disorders, cancer, inflammation, and glaucoma. Up to this point, many classes of compounds have been successfully synthesized and identified as potent human adenosine receptor antagonists. In this paper, an overview of the structure-activity relationship (SAR) profiles of promising nonxanthine pyrazolo derivatives is reported and discussed. We have emphasized the SAR for some representative structures such as pyrazolo-[4,3-e]-1,2,4-triazolo-[1,5-c]pyrimidines; pyrazolo-[3,4-c] or -[4,3-c]quinolines; pyrazolo-[4,3-d]pyrimidinones; pyrazolo-[3,4-d]pyrimidines and pyrazolo-[1,5-a]pyridines. This overview not only clarifies the structural requirements deemed essential for affinity towards individual adenosine receptor subtypes, but it also sheds light on the rational design and optimization of existing structural templates to allow us to conceive new, more potent adenosine receptor antagonists. PMID:25954519

  15. Tremorgenic indole alkaloids potently inhibit smooth muscle high-conductance calcium-activated potassium channels.

    PubMed

    Knaus, H G; McManus, O B; Lee, S H; Schmalhofer, W A; Garcia-Calvo, M; Helms, L M; Sanchez, M; Giangiacomo, K; Reuben, J P; Smith, A B

    1994-05-17

    Tremorgenic indole alkaloids produce neurological disorders (e.g., staggers syndromes) in ruminants. The mode of action of these fungal mycotoxins is not understood but may be related to their known effects on neurotransmitter release. To determine whether these effects could be due to inhibition of K+ channels, the interaction of various indole diterpenes with high-conductance Ca(2+)-activated K+ (maxi-K) channels was examined. Paspalitrem A, paspalitrem C, aflatrem, penitrem A, and paspalinine inhibit binding of [125I]charybdotoxin (ChTX) to maxi-K channels in bovine aortic smooth muscle sarcolemmal membranes. In contrast, three structurally related compounds, paxilline, verruculogen, and paspalicine, enhanced toxin binding. As predicted from the binding studies, covalent incorporation of [125I]ChTX into the 31-kDa subunit of the maxi-K channel was blocked by compounds that inhibit [125I]ChTX binding and enhanced by compounds that stimulate [125I]ChTX binding. Modulation of [125I]ChTX binding was due to allosteric mechanisms. Despite their different effects on binding of [125I]ChTX to maxi-K channels, all compounds potently inhibited maxi-K channels in electrophysiological experiments. Other types of voltage-dependent or Ca(2+)-activated K+ channels examined were not affected. Chemical modifications of paxilline indicate a defined structure-activity relationship for channel inhibition. Paspalicine, a deshydroxy analog of paspalinine lacking tremorgenic activity, also potently blocked maxi-K channels. Taken together, these data suggest that indole diterpenes are the most potent nonpeptidyl inhibitors of maxi-K channels identified to date. Some of their pharmacological properties could be explained by inhibition of maxi-K channels, although tremorgenicity may be unrelated to channel block. PMID:7514038

  16. A novel peptide with potent and broad-spectrum antiviral activities against multiple respiratory viruses.

    PubMed

    Zhao, Hanjun; Zhou, Jie; Zhang, Ke; Chu, Hin; Liu, Dabin; Poon, Vincent Kwok-Man; Chan, Chris Chung-Sing; Leung, Ho-Chuen; Fai, Ng; Lin, Yong-Ping; Zhang, Anna Jin-Xia; Jin, Dong-Yan; Yuen, Kwok-Yung; Zheng, Bo-Jian

    2016-01-01

    A safe, potent and broad-spectrum antiviral is urgently needed to combat emerging respiratory viruses. In light of the broad antiviral activity of β-defensins, we tested the antiviral activity of 11 peptides derived from mouse β-defensin-4 and found that a short peptide, P9, exhibited potent and broad-spectrum antiviral effects against multiple respiratory viruses in vitro and in vivo, including influenza A virus H1N1, H3N2, H5N1, H7N7, H7N9, SARS-CoV and MERS-CoV. The antiviral activity of P9 was attributed to its high-affinity binding to viral glycoproteins, as well as the abundance of basic amino acids in its composition. After binding viral particles through viral surface glycoproteins, P9 entered into cells together with the viruses via endocytosis and prevented endosomal acidification, which blocked membrane fusion and subsequent viral RNA release. This study has paved the avenue for developing new prophylactic and therapeutic agents with broad-spectrum antiviral activities. PMID:26911565

  17. A novel peptide with potent and broad-spectrum antiviral activities against multiple respiratory viruses

    PubMed Central

    Zhao, Hanjun; Zhou, Jie; Zhang, Ke; Chu, Hin; Liu, Dabin; Poon, Vincent Kwok-Man; Chan, Chris Chung-Sing; Leung, Ho-Chuen; Fai, Ng; Lin, Yong-Ping; Zhang, Anna Jin-Xia; Jin, Dong-Yan; Yuen, Kwok-Yung; Zheng, Bo-Jian

    2016-01-01

    A safe, potent and broad-spectrum antiviral is urgently needed to combat emerging respiratory viruses. In light of the broad antiviral activity of β-defensins, we tested the antiviral activity of 11 peptides derived from mouse β-defensin-4 and found that a short peptide, P9, exhibited potent and broad-spectrum antiviral effects against multiple respiratory viruses in vitro and in vivo, including influenza A virus H1N1, H3N2, H5N1, H7N7, H7N9, SARS-CoV and MERS-CoV. The antiviral activity of P9 was attributed to its high-affinity binding to viral glycoproteins, as well as the abundance of basic amino acids in its composition. After binding viral particles through viral surface glycoproteins, P9 entered into cells together with the viruses via endocytosis and prevented endosomal acidification, which blocked membrane fusion and subsequent viral RNA release. This study has paved the avenue for developing new prophylactic and therapeutic agents with broad-spectrum antiviral activities. PMID:26911565

  18. Discovery of a Selective Inhibitor of Oncogenic B-Raf Kinase With Potent Antimelanoma Activity

    SciTech Connect

    Tsai, J.; Lee, J.T.; Wang, W.; Zhang, J.; Cho, H.; Mamo, S.; Bremer, R.; Gillette, S.; Kong, J.; Haass, N.K.; Sproesser, K.; Li, L.; Smalley, K.S.M.; Fong, D.; Zhu, Y.-L.; Marimuthu, A.; Nguyen, H.; Lam, B.; Liu, J.; Cheung, I.; Rice, J.

    2009-05-26

    BRAF{sup V600E} is the most frequent oncogenic protein kinase mutation known. Furthermore, inhibitors targeting 'active' protein kinases have demonstrated significant utility in the therapeutic repertoire against cancer. Therefore, we pursued the development of specific kinase inhibitors targeting B-Raf, and the V600E allele in particular. By using a structure-guided discovery approach, a potent and selective inhibitor of active B-Raf has been discovered. PLX4720, a 7-azaindole derivative that inhibits B-Raf{sup V600E} with an IC{sub 50} of 13 nM, defines a class of kinase inhibitor with marked selectivity in both biochemical and cellular assays. PLX4720 preferentially inhibits the active B-Raf{sup V600E} kinase compared with a broad spectrum of other kinases, and potent cytotoxic effects are also exclusive to cells bearing the V600E allele. Consistent with the high degree of selectivity, ERK phosphorylation is potently inhibited by PLX4720 in B-Raf{sup V600E}-bearing tumor cell lines but not in cells lacking oncogenic B-Raf. In melanoma models, PLX4720 induces cell cycle arrest and apoptosis exclusively in B-Raf{sup V600E}-positive cells. In B-Raf{sup V600E}-dependent tumor xenograft models, orally dosed PLX4720 causes significant tumor growth delays, including tumor regressions, without evidence of toxicity. The work described here represents the entire discovery process, from initial identification through structural and biological studies in animal models to a promising therapeutic for testing in cancer patients bearing B-Raf{sup V600E}-driven tumors.

  19. Bipiperidinyl carboxylic acid amides as potent, selective, and functionally active CCR4 antagonists.

    PubMed

    Kuhn, Cyrille F; Bazin, Marc; Philippe, Laurence; Zhang, Jiansu; Tylaska, Laurie; Miret, Juan; Bauer, Paul H

    2007-09-01

    A cell-based assay for the chemokine G-protein-coupled receptor CCR4 was developed, and used to screen a small-molecule compound collection in a multiplex format. A series of bipiperidinyl carboxylic acid amides amenable to parallel chemistry were derived that were potent and selective antagonists of CCR4. One prototype compound was shown to be active in a functional model of chemotaxis, making it a useful chemical tool to explore the role of CCR4 in asthma, allergy, diabetes, and cancer.

  20. The X protein of hepatitis B virus coactivates potent activation domains.

    PubMed Central

    Haviv, I; Vaizel, D; Shaul, Y

    1995-01-01

    Transactivation by hepatitis B virus X protein (pX) is promiscuous, but it requires cellular activators. To study the mode of action of pX, we coexpressed pX with Gal4-derived activators in a cotransfection system. Twelve different activators bearing different types of activation domains were compared for their response to pX. Because pX indirectly increases the amount of the activators, tools were developed to compare samples with equivalent amount of activators. We demonstrate that pX preferentially coactivates potent activators, especially those with acidic activation domains. Weak activators with nonacidic activation domains are not potentiated by pX. Interestingly, Gal4E1a, which is not rich in acidic residues but interacts with similar molecular targets, also responds to pX. The response to pX correlated with the strength of the activation domain. Collectively, these data imply that pX is a coactivator, which offers a molecular basis for the pleiotropic effects of pX on transcription. PMID:7823923

  1. Structure-antitussive activity relationships of naltrindole derivatives. Identification of novel and potent antitussive agents.

    PubMed

    Sakami, Satoshi; Maeda, Masayuki; Kawai, Koji; Aoki, Takumi; Kawamura, Kuniaki; Fujii, Hideaki; Hasebe, Ko; Nakajima, Mayumi; Endo, Takashi; Ueno, Shinya; Ito, Tsuyoshi; Kamei, Junzo; Nagase, Hiroshi

    2008-08-14

    We have previously reported antitussive effects of naltrindole (NTI), a typical delta opioid receptor antagonist, in a rat model. The ED50 values of NTI by intraperitoneal and peroral injections were 104 microg/kg and 1840 microg/kg, respectively, comparable to those of codeine. Codeine, one of the most reliable centrally acting antitussive drugs, has micro agonist activity and thus the same side effects as morphine, e.g., constipation, dependency, and respiratory depression. Because NTI is a delta opioid antagonist, its derivatives have potential as highly potent antitussives, free from the mu opioid agonist side effects. We attempted to optimize the NTI derivatives to develop novel antitussive agents. On the basis of the studies of structure-antitussive activity relationships of alkyl substituted NTI derivatives, we designed NTI derivatives with extra ring fused structures. As a clinical candidate, we identified a highly potent new compound, (5R,9R,13S,14S)-17-cyclopropylmethyl-6,7-didehydro-4,5-epoxy-5',6'-dihydro-3-methoxy-4'H-pyrrolo[3,2,1-ij]quinolino[2',1':6,7]morphinan-14-ol (5b) methanesulfonate (TRK-850) which was effective even by oral administration (ED50 6.40 microg/kg).

  2. Novel Radiolytic Rotenone Derivative, Rotenoisin B with Potent Anti-Carcinogenic Activity in Hepatic Cancer Cells.

    PubMed

    Badaboina, Srilatha; Bai, Hyoung-Woo; Na, Yun Hee; Park, Chul-Hong; Kim, Tae Hoon; Lee, Tae-Hoon; Chung, Byung Yeoup

    2015-01-01

    Rotenone, isolated from roots of derris plant, has been shown to possess various biological activities, which lead to attempting to develop a potent drug against several diseases. However, recent studies have demonstrated that rotenone has the potential to induce several adverse effects such as a neurodegenerative disease. Radiolytic transformation of the rotenone with gamma-irradiation created a new product, named rotenoisin B. The present work was designed to investigate the anticancer activity of rotenoisin B with low toxicity and its molecular mechanism in hepatic cancer cells compared to a parent compound, rotenone. Our results showed rotenoisin B inhibited hepatic cancer cells' proliferation in a dose dependent manner and increased in apoptotic cells. Interestingly, rotenoisin B showed low toxic effects on normal cells compared to rotenone. Mitochondrial transmembrane potential has been decreased, which leads to cytochrome c release. Down regulation of anti-apoptotic Bcl-2 levels as well as the up regulation of proapoptotic Bax levels were observed. The cleaved PARP (poly ADP-ribose polymerase) level increased as well. Moreover, phosphorylation of extracellular signal regulated kinase (ERK) and p38 slightly up regulated and intracellular reactive oxygen species (ROS) increased as well as cell cycle arrest predominantly at the G2/M phase observed. These results suggest that rotenoisin B might be a potent anticancer candidate similar to rotenone in hepatic cancer cells with low toxicity to normal cells even at high concentrations compared to rotenone. PMID:26213921

  3. Novel Radiolytic Rotenone Derivative, Rotenoisin B with Potent Anti-Carcinogenic Activity in Hepatic Cancer Cells

    PubMed Central

    Badaboina, Srilatha; Bai, Hyoung-Woo; Na, Yun Hee; Park, Chul-Hong; Kim, Tae Hoon; Lee, Tae-Hoon; Chung, Byung Yeoup

    2015-01-01

    Rotenone, isolated from roots of derris plant, has been shown to possess various biological activities, which lead to attempting to develop a potent drug against several diseases. However, recent studies have demonstrated that rotenone has the potential to induce several adverse effects such as a neurodegenerative disease. Radiolytic transformation of the rotenone with gamma-irradiation created a new product, named rotenoisin B. The present work was designed to investigate the anticancer activity of rotenoisin B with low toxicity and its molecular mechanism in hepatic cancer cells compared to a parent compound, rotenone. Our results showed rotenoisin B inhibited hepatic cancer cells’ proliferation in a dose dependent manner and increased in apoptotic cells. Interestingly, rotenoisin B showed low toxic effects on normal cells compared to rotenone. Mitochondrial transmembrane potential has been decreased, which leads to cytochrome c release. Down regulation of anti-apoptotic Bcl-2 levels as well as the up regulation of proapoptotic Bax levels were observed. The cleaved PARP (poly ADP-ribose polymerase) level increased as well. Moreover, phosphorylation of extracellular signal regulated kinase (ERK) and p38 slightly up regulated and intracellular reactive oxygen species (ROS) increased as well as cell cycle arrest predominantly at the G2/M phase observed. These results suggest that rotenoisin B might be a potent anticancer candidate similar to rotenone in hepatic cancer cells with low toxicity to normal cells even at high concentrations compared to rotenone. PMID:26213921

  4. Dimers of melampomagnolide B exhibit potent anticancer activity against hematological and solid tumor cells

    PubMed Central

    Janganati, Venumadhav; Ponder, Jessica; Jordan, Craig T.; Borrelli, Michael J.; Penthala, Narsimha Reddy; Crooks, Peter A.

    2016-01-01

    A series of novel carbamate and carbonate dimers of melampomagnolide B (MMB) have been synthesized by reaction of the MMB-triazole carbamate synthon 6 with various terminal diamino and dihydroxy alkanes. The resulting dimeric products 7b, 7c and 7f were selected and evaluated for anticancer activity against a panel of 60 human hematological and solid tumor cell lines. The most active compounds, 7b, 7c and 7f, exhibited GI50 values in the range 250-780 nM against the majority of leukemia cell lines in the tumor cell panel. Specifically, compounds 7b and 7f exhibited potent growth inhibition against non-small cell lung cancer cell lines NCI-H522 (GI50 = 160 nM) and HOP-92 (GI50 = 170 nM), respectively. Also, compound 7f also potently inhibited the growth of melanoma cell lines LOX IMVI, MALME-3M, and UACC-62 (GI50 values = 170, 190 and 190 nM, respectively); breast cancer cell line MDA-MB-468 (GI50 = 190 nM); colon cancer cell line HCT-116 (GI50 = 190 nM); and renal cancer cell line RXF 393 (GI50 = 160 nM). Compound 7f and the simple dicarbonate dimer of MMB (8) showed anticancer activity 300-fold and 1 × 106-fold, respectively, more cytotoxic than 7f and DMAPT at a concentration of 10 μM against rat 9L-SF gliosarcoma cells. The dimeric compounds 7a-7j & 8 were also screened for antileukemic activity against M9-ENL1 acute myelogenous leukemia (AML) cells and primary AML cell specimens. These compounds exhibited two to twelve-fold more potent antileukemic activity (EC50 = 0.5-2.9 μM) against the M9-ENL1 cell line when compared to parthenolide (EC50 = 6.0 μM). The dimeric analogues were also active against the primary AML cell specimens in the nanomolar to lower micromolar range and exhibited two to ten-fold more potent antileukemic activity (EC50 = 0.86-4.2 μM) when compared to parthenolide (EC50 = 2.5-16 μM). Thus, dimer 7f exhibited promising anticancer activity against a variety of both hematological and solid human tumor cell lines, while dimer 8 was

  5. Benzoxazolone Carboxamides: Potent and Systemically Active Inhibitors of Intracellular Acid Ceramidase**

    PubMed Central

    Pizzirani, Daniela; Bach, Anders; Realini, Natalia; Armirotti, Andrea; Mengatto, Luisa; Bauer, Inga; Girotto, Stefania; Pagliuca, Chiara; De Vivo, Marco; Summa, Maria; Ribeiro, Alison; Piomelli, Daniele

    2015-01-01

    The ceramides are a family of bioactive lipid-derived messengers involved in the control of cellular senescence, inflammation, and apoptosis. Ceramide hydrolysis by acid ceramidase (AC) stops the biological activity of these substances and influences survival and function of normal and neoplastic cells. Because of its central role in the ceramide metabolism, AC may offer a novel molecular target in disorders with dysfunctional ceramide-mediated signaling. Here, a class of benzoxazolone carboxamides is identified as the first potent and systemically active inhibitors of AC. Prototype members of this class inhibit AC with low nanomolar potency by covalent binding to the catalytic cysteine. Their metabolic stability and high in vivo efficacy suggest that these compounds may be used as probes to investigate the roles of ceramide in health and disease, and that this scaffold may represent a promising starting point for the development of novel therapeutic agents. PMID:25395373

  6. Complex secondary metabolites from Ludwigia leptocarpa with potent antibacterial and antioxidant activities.

    PubMed

    Mabou, Florence Déclaire; Tamokou, Jean-de-Dieu; Ngnokam, David; Voutquenne-Nazabadioko, Laurence; Kuiate, Jules-Roger; Bag, Prasanta Kumar

    2016-01-01

    Diarrhea continues to be one of the most common causes of morbidity and mortality among infants and children in developing countries. The aim of the present study was to evaluate the antibacterial and antioxidant activities of extracts and compounds from Ludwigia leptocarpa, a plant traditionally used for its vermifugal, anti-dysenteric, and antimicrobial properties. A methanol extract was prepared by maceration of the dried plant and this was successively extracted with ethyl acetate to obtain an EtOAc extract and with n-butanol to obtain an n-BuOH extract. Column chromatography of the EtOAc and n-BuOH extracts was followed by purification of different fractions, leading to the isolation of 10 known compounds. Structures of isolated compounds were assigned on the basis of spectral analysis and by comparison to structures of compounds described in the literature. Antioxidant activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and gallic acid equivalent antioxidant capacity (GAEAC) assays. Antibacterial activity was assessed with the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) with respect to strains of a Gram-positive bacterium, Staphylococcus aureus (a major cause of community and hospital-associated infection), and Gram-negative multi-drug-resistant bacteria, Vibrio cholerae (a cause of cholera) and Shigella flexneri (a cause of shigellosis). All of the extracts showed different degrees of antioxidant and antibacterial activities. 2β-hydroxyoleanolic acid, (2R,3S,2''S)-3''',4',4''',5,5'',7,7''-heptahydroxy-3,8"-biflavanone, and luteolin-8-C-glucoside displayed the most potent antibacterial and antioxidant properties, and these properties were in some cases equal to or more potent than those of reference drugs. Overall, the present results show that L. leptocarpa has the potential to be a natural source of anti-diarrheal and antioxidant products, so further investigation is warranted. PMID:27431270

  7. Basis Tetrapeptides as Potent Intracellular Inhibitors of type A Botulinum Neurotoxin Protease Activity

    SciTech Connect

    Hale, M.; Swaminathan, S.; Oyler, G.; Ahmed, S. A.

    2011-01-21

    Botulinum neurotoxins (BoNT) are the most potent of all toxins that cause flaccid muscle paralysis leading to death. They are also potential biothreat agents. A systematic investigation of various short peptide inhibitors of the BoNT protease domain with a 17-residue peptide substrate led to arginine-arginine-glycine-cysteine having a basic tetrapeptide structure as the most potent inhibitor. When assayed in the presence of dithiothreitol (DTT), the inhibitory effect was drastically reduced. Replacing the terminal cysteine with one hydrophobic residue eliminated the DTT effect but with two hydrophobic residues made the pentapeptide a poor inhibitor. Replacing the first arginine with cysteine or adding an additional cysteine at the N terminus did not improve inhibition. When assessed using mouse brain lysates, the tetrapeptides also inhibited BoNT/A cleavage of the endogenous SNAP-25. The peptides penetrated the neuronal cell lines, N2A and BE(2)-M17, without adversely affecting metabolic functions as measured by ATP production and P-38 phosphorylation. Biological activity of the peptides persisted within cultured chick motor neurons and rat and mouse cerebellar neurons for more than 40 h and inhibited BoNT/A protease action inside the neurons in a dose- and time-dependent fashion. Our results define a tetrapeptide as the smallest peptide inhibitor in the backdrop of a large substrate protein of 200+ amino acids having multiple interaction regions with its cognate enzyme. The inhibitors should also be valuable candidates for drug development.

  8. Identification of Selective and Potent Inhibitors of Fibroblast Activation Protein and Prolyl Oligopeptidase

    PubMed Central

    Poplawski, Sarah E.; Lai, Jack H.; Li, Youhua; Jin, Zhiping; Liu, Yuxin; Wu, Wengen; Wu, Yong; Zhou, Yuhong; Sudmeier, James L.; Sanford, David G.; Bachovchin, William W.

    2014-01-01

    Fibroblast activation protein (FAP) is a serine protease selectively expressed on reactive stromal fibroblasts of epithelial carcinomas. It is widely believed to play a role in tumor invasion and metastasis and therefore to represent a potential new drug target for cancer. Investigation into its biological function, however, has been hampered by the current unavailability of selective inhibitors. The challenge has been in identifying inhibitors that are selective for FAP over both the dipeptidyl peptidases (DPPs), with which it shares exopeptidase specificity, and prolyl oligopeptidase (PREP), with which it shares endopeptidase specificity. Here, we report the first potent FAP inhibitor with selectivity over both the DPPs and PREP, N-(pyridine-4-carbonyl)-d-Ala-boroPro (ARI-3099, 6). We also report a similarly potent and selective PREP inhibitor, N-(pyridine-3-carbonyl)-Val-boroPro (ARI-3531, 22). Both are boronic acid based inhibitors, demonstrating that high selectivity can be achieved using this electrophile. The inhibitors are stable, easy to synthesize, and should prove to be useful in helping to elucidate the biological functions of these two unique and interesting enzymes, as well as their potential as drug targets. PMID:23594271

  9. Novel Chalcone Derivatives as Potent Nrf2 Activators in Mice and Human Lung Epithelial Cells

    PubMed Central

    Kumar, Vineet; Kumar, Sarvesh; Hassan, Mohammad; Wu, Hailong; Thimmulappa, Rajesh K.; Kumar, Amit; Sharma, Sunil K.; Parmar, Virinder S.; Biswal, Shyam; Malhotra, Sanjay V.

    2011-01-01

    Nrf2-mediated activation of antioxidant response element is a central part of molecular mechanisms governing the protective function of phase II detoxification and antioxidant enzymes against carcinogenesis, oxidative stress and inflammation. Nrf2 is sequestered in the cytoplasm by its repressor, Keap1. We have designed and synthesized novel chalcone derivatives as Nrf2 activators. The potency of these compounds was measured by the expression of Nrf2 dependent antioxidant genes, GCLM, NQO1 and HO1, in human lung epithelial cells; while the cytotoxicity was analyzed using MTT assay. In vivo potency of identified lead compounds to activate Nrf2 was evaluated using mouse model. Our studies showed 2-trifluoromethyl-2’-methoxychalone (2b) to be a potent activator of Nrf2, both, in vitro and in mice. Additional experiments showed that the activation of Nrf2 by this compound is independent of reactive oxygen species or redox changes. We have discussed a quantitative structure-activity relationship and proposed a possible mechanism of Nrf2 activation. PMID:21539383

  10. The EDLL motif: a potent plant transcriptional activation domain from AP2/ERF transcription factors.

    PubMed

    Tiwari, Shiv B; Belachew, Alemu; Ma, Siu Fong; Young, Melinda; Ade, Jules; Shen, Yu; Marion, Colleen M; Holtan, Hans E; Bailey, Adina; Stone, Jeffrey K; Edwards, Leslie; Wallace, Andreah D; Canales, Roger D; Adam, Luc; Ratcliffe, Oliver J; Repetti, Peter P

    2012-06-01

    In plants, the ERF/EREBP family of transcriptional regulators plays a key role in adaptation to various biotic and abiotic stresses. These proteins contain a conserved AP2 DNA-binding domain and several uncharacterized motifs. Here, we describe a short motif, termed 'EDLL', that is present in AtERF98/TDR1 and other clade members from the same AP2 sub-family. We show that the EDLL motif, which has a unique arrangement of acidic amino acids and hydrophobic leucines, functions as a strong activation domain. The motif is transferable to other proteins, and is active at both proximal and distal positions of target promoters. As such, the EDLL motif is able to partly overcome the repression conferred by the AtHB2 transcription factor, which contains an ERF-associated amphiphilic repression (EAR) motif. We further examined the activation potential of EDLL by analysis of the regulation of flowering time by NF-Y (nuclear factor Y) proteins. Genetic evidence indicates that NF-Y protein complexes potentiate the action of CONSTANS in regulation of flowering in Arabidopsis; we show that the transcriptional activation function of CONSTANS can be substituted by direct fusion of the EDLL activation motif to NF-YB subunits. The EDLL motif represents a potent plant activation domain that can be used as a tool to confer transcriptional activation potential to heterologous DNA-binding proteins.

  11. Isolation and purification of human biliary vesicles with potent cholesterol-nucleation-promoting activity.

    PubMed

    Miquel, J F; Rigotti, A; Rojas, E; Brandan, E; Nervi, F

    1992-02-01

    1. Cholesterol nucleation is a critical step in the formation of cholesterol gallstones. This nucleation takes place after aggregation and fusion of cholesterol-rich biliary vesicles, a process probably modulated by biliary proteins. The present study was conducted to identify specific proteins associated with native cholesterol-rich biliary vesicles and to explore their effect on the cholesterol-nucleation time of supersaturated artificial bile. 2. Hepatic bile was obtained from six patients with cholesterol gallstone disease. Biliary vesicles were isolated by ultracentrifugation and were purified by gel filtration chromatography. A small amount of protein (less than 1% by weight) remained associated with the purified cholesterol-rich biliary vesicles. The electrophoretic profile of these proteins was remarkably similar in all six patients, showing the presence of at least six polypeptides (of molecular mass from 52 to 200 kDa), five of them having carbohydrate residues (except the 52 kDa one). The effect of reconstituted biliary vesicle solutions, containing their specific vesicular proteins, on cholesterol-nucleation time was studied by mixing the vesicle solution with artificial supersaturated bile. A potent cholesterol-pronucleating activity, reflected in a 20-70% reduction in nucleation time, was present in the biliary vesicle solutions compared with control solutions having a similar lipid composition. The pronucleating activity disappeared on heating and was not detected in the micellar fraction containing the major proportion of biliary proteins. 3. These results indicate that cholesterol-rich biliary vesicles containing a unique and defined glycoprotein profile can be isolated and purified from human hepatic bile. The potent cholesterol-pronucleating activity of the biliary vesicles from patients with gallstones was unrelated to their lipid composition or cholesterol content.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Visna virus Tat protein: a potent transcription factor with both activator and suppressor domains.

    PubMed Central

    Carruth, L M; Hardwick, J M; Morse, B A; Clements, J E

    1994-01-01

    Visna virus is a pathogenic lentivirus of sheep tat is distantly related to the primate lentiviruses, including human immunodeficiency virus type 1. The visna virus genome encodes a small regulatory protein, Tat, which is necessary for efficient viral replication and enhanced viral transcription. To investigate the mechanism of action of the visna Tat protein and to localize the protein domain(s) responsible for transcriptional activation, chimeric proteins containing visna virus Tat sequences fused to the DNA binding domain of the yeast transactivation factor GAL4 (residues 1 to 147) were made. The GAL4-Tat fusion proteins were transfected into cells and tested for the ability to activate the adenovirus E1b promoter via upstream GAL4 DNA binding sites. Full-length GAL4-Tat fusion proteins were weak transactivators in this system, giving only a two- to fourfold increase in transcription in several cell types, including HeLa and sheep choroid plexus cells. In contrast, fusion of the N-terminal region of the Tat protein to GAL4 revealed a potent activation domain. Amino acids 13 to 38 appeared to be the most critical for activation. No other region of the protein showed any activation in the GAL4 system. This N-terminal region of the visna virus Tat protein has a large number of acidic and hydrophobic residues, suggesting that Tat has an acidic activation domain common to many transcriptional transactivators. Mutations in hydrophobic and bulky aromatic residues dramatically reduced the activity of the chimeric protein. Competition experiments suggest that mechanism of the visna virus Tat activation domain may closely resemble that of the herpesvirus activator VP16 and human immunodeficiency virus Tat, a related lentivirus activator, since both significantly reduce the level of visna virus Tat activation. Finally, a domain between residues 39 and 53 was identified in the Tat protein that, in the GAL4 system, negatively regulates activation by Tat. Images PMID:8083955

  13. Potent antagonistic activity of Egyptian Lactobacillus plantarum against multiresistant and virulent food-associated pathogens

    PubMed Central

    Al-Madboly, Lamiaa A.; Abdullah, Abeer K.

    2015-01-01

    Recent years have shown a growing interest to replace the administration of antibiotics with the application of probiotics. The aim of our investigation was to screen for promising strains with broad antimicrobial activity and also more resistant to the challenges met in the gastrointestinal tract. In our study, only 32 out of 50 (64%) probiotic isolates showed antagonistic activity against certain major extensively and pandrug-resistant Gram-positive and -negative food-borne pathogens. Fifteen L. plantarum isolates had a broad antibacterial spectrum. Among these isolates, only five presented potent antibacterial activity relative to previous studies. The recorded inhibition zone diameter ranged from 25 to 44 mm. Pronounced cell-free supernatant activities (6400–25,600 AU/ml) were commonly detected at the end of the logarithmic phase at 37°C. A marked increase in the range of activity (12,800–51,200 AU/ml) was recorded after the addition of 0.9% Na Cl to the media. Moreover, subjecting these isolates to different stressors, including high temperature, low pH, and different concentrations of bile and Na Cl, revealed different responses, and only two out of the five L. plantarum isolates showed marked resistance to all of the stress factors. Accordingly, this study highlights the intense and broad antagonistic activity induced by L. plantarum against various food associated pathogens, and their ability to resist different stressors suggests that they can be used in the food and pharmaceutical industry. PMID:26029169

  14. Galloylated proanthocyanidins from shea (Vitellaria paradoxa) meal have potent anthelmintic activity against Ascaris suum.

    PubMed

    Ramsay, A; Williams, A R; Thamsborg, S M; Mueller-Harvey, I

    2016-02-01

    Proanthocyanidins (PA) from shea (Vitellaria paradoxa) meal were investigated by thiolytic degradation with benzyl mercaptan and the reaction products were analysed by high performance liquid chromatography-mass spectrometry. These PA were galloylated (≈40%), contained only B-type linkages and had a high proportion of prodelphinidins (>70%). The mean degree of polymerisation was 8 (i.e. average molecular size was 2384Da) and epigallocatechin gallate (EGCg) was the major flavan-3-ol subunit in PA. Shea meal also proved to be a potentially valuable source for extracting free flavan-3-ol-O-gallates, especially EGCg (575mg/kg meal), which is known for its health and anti-parasitic benefits. Proanthocyanidins were isolated and tested for bioactivity against Ascaris suum, which is an important parasite of pigs. Migration and motility tests revealed that these PA have potent activity against this parasitic nematode. PMID:26708339

  15. Designed, synthetically accessible bryostatin analogues potently induce activation of latent HIV reservoirs in vitro

    NASA Astrophysics Data System (ADS)

    Dechristopher, Brian A.; Loy, Brian A.; Marsden, Matthew D.; Schrier, Adam J.; Zack, Jerome A.; Wender, Paul A.

    2012-09-01

    Bryostatin is a unique lead in the development of potentially transformative therapies for cancer, Alzheimer's disease and the eradication of HIV/AIDS. However, the clinical use of bryostatin has been hampered by its limited supply, difficulties in accessing clinically relevant derivatives, and side effects. Here, we address these problems through the step-economical syntheses of seven members of a new family of designed bryostatin analogues using a highly convergent Prins-macrocyclization strategy. We also demonstrate for the first time that such analogues effectively induce latent HIV activation in vitro with potencies similar to or better than bryostatin. Significantly, these analogues are up to 1,000-fold more potent in inducing latent HIV expression than prostratin, the current clinical candidate for latent virus induction. This study provides the first demonstration that designed, synthetically accessible bryostatin analogues could serve as superior candidates for the eradication of HIV/AIDS through induction of latent viral reservoirs in conjunction with current antiretroviral therapy.

  16. Galloylated proanthocyanidins from shea (Vitellaria paradoxa) meal have potent anthelmintic activity against Ascaris suum.

    PubMed

    Ramsay, A; Williams, A R; Thamsborg, S M; Mueller-Harvey, I

    2016-02-01

    Proanthocyanidins (PA) from shea (Vitellaria paradoxa) meal were investigated by thiolytic degradation with benzyl mercaptan and the reaction products were analysed by high performance liquid chromatography-mass spectrometry. These PA were galloylated (≈40%), contained only B-type linkages and had a high proportion of prodelphinidins (>70%). The mean degree of polymerisation was 8 (i.e. average molecular size was 2384Da) and epigallocatechin gallate (EGCg) was the major flavan-3-ol subunit in PA. Shea meal also proved to be a potentially valuable source for extracting free flavan-3-ol-O-gallates, especially EGCg (575mg/kg meal), which is known for its health and anti-parasitic benefits. Proanthocyanidins were isolated and tested for bioactivity against Ascaris suum, which is an important parasite of pigs. Migration and motility tests revealed that these PA have potent activity against this parasitic nematode.

  17. Polyethyleneimine is a potent mucosal adjuvant for glycoproteins with innate and adaptive immune activating properties

    PubMed Central

    Wegmann, Frank; Gartlan, Kate H; Harandi, Ali M; Brinckmann, Sarah A; Coccia, Margherita; Hillson, William R; Kok, Wai Ling; Cole, Suzanne; Ho, Ling-Pei; Lambe, Teresa; Puthia, Manoj; Svanborg, Catharina; Scherer, Erin M; Krashias, George; Williams, Adam; Blattman, Joseph N; Greenberg, Philip D; Flavell, Richard A; Moghaddam, Amin E; Sheppard, Neil C; Sattentau, Quentin J

    2012-01-01

    There are no mucosal adjuvant formulations licensed for human use, despite protection against many mucosally-transmitted infections probably requiring immunity at the site of pathogen entry1. Polyethyleneimines (PEI) are organic polycations used as nucleic acid transfection reagents in vitro, and gene and DNA vaccine delivery vehicles in vivo2, 3. Here we show that PEI has unexpected and unusually potent mucosal adjuvant activity in conjunction with viral subunit glycoprotein antigens. Single intranasal administration of influenza HA or HSV-2 gD with PEI elicited robust protection from otherwise lethal infection, and was superior to existing experimental mucosal adjuvants. PEI formed nanoscale complexes with antigen that were taken up by antigen presenting cells in vitro and in vivo, promoted DC trafficking to draining lymph nodes and induced non-proinflammatory cytokine responses. PEI adjuvanticity required release of host dsDNA that triggered Irf-3-dependent signaling. PEI therefore merits further investigation as a mucosal adjuvant for human use. PMID:22922673

  18. Discovery of HDAC Inhibitors with Potent Activity Against Multiple Malaria Parasite Life Cycle Stages

    PubMed Central

    Hansen, Finn K.; Sumanadasa, Subathdrage D. M.; Stenzel, Katharina; Duffy, Sandra; Meister, Stephan; Marek, Linda; Schmetter, Rebekka; Kuna, Krystina; Hamacher, Alexandra; Mordmüller, Benjamin; Kassack, Matthias U.; Winzeler, Elizabeth A.; Avery, Vicky M.; Andrews, Katherine T.; Kurz, Thomas

    2015-01-01

    In this work we investigated the antiplasmodial activity of a series of HDAC inhibitors containing an alkoxyamide connecting-unit linker region. HDAC inhibitor 1a (LMK235), previously shown to be a novel and specific inhibitor of human HDAC4 and 5, was used as a starting point to rapidly construct a mini-library of HDAC inhibitors using a straightforward solid-phase supported synthesis. Several of these novel HDAC inhibitors were found to have potent in vitro activity against asexual stage P. falciparum malaria parasites. Representative compounds were shown to hyperacetylate P. falciparum histones and to inhibit deacetylase activity of recombinant PfHDAC1 and P. falciparum nuclear extracts. All compounds were also screened in vitro for activity against P. berghei exo-erythrocytic stages and selected compounds were further tested against late stage (IV and V) P. falciparum gametocytes. Of note, some compounds showed nanomolar activity against all three life cycle stages tested (asexual, exo-erythrocytic and gametocyte stages) and several compounds displayed significantly increased parasite selectivity compared to the reference HDAC inhibitor suberoylanilide hydroxamic acid (SAHA). These data suggest that it may be possible to develop HDAC inhibitors that target multiple malaria parasite life cycle stages. PMID:24904967

  19. Quinoxaline N-oxide containing potent angiotensin II receptor antagonists: synthesis, biological properties, and structure-activity relationships.

    PubMed

    Kim, K S; Qian, L; Bird, J E; Dickinson, K E; Moreland, S; Schaeffer, T R; Waldron, T L; Delaney, C L; Weller, H N; Miller, A V

    1993-08-01

    A series of novel quinoxaline heterocycle containing angiotensin II receptor antagonist analogs were prepared. This heterocycle was coupled to the biphenyl moiety via an oxygen atom linker instead of a carbon atom. Many of these analogs exhibit very potent activity and long duration of effect. Interestingly, the N-oxide quinoxaline analog was more potent than the nonoxidized quinoxaline as in the comparison of compounds 5 vs 30. In order to improve oral activity, the carboxylic acid function of these compounds was converted to the double ester. This change did result in an improvement in oral activity as represented by compound 44.

  20. Discovery of Metal Ions Chelator Quercetin Derivatives with Potent Anti-HCV Activities.

    PubMed

    Zhong, Dongwei; Liu, Mingming; Cao, Yang; Zhu, Yelin; Bian, Shihui; Zhou, Jiayi; Wu, Fengjie; Ryu, Kum-Chol; Zhou, Lu; Ye, Deyong

    2015-04-16

    Analogues or isosteres of α,γ-diketoacid (DKA) 1a show potent inhibition of hepatitis C virus (HCV) NS5B polymerase through chelation of the two magnesium ions at the active site. The anti-HCV activity of the flavonoid quercetin (2) could partly be attributed to it being a structural mimic of DKAs. In order to delineate the structural features required for the inhibitory effect and improve the anti-HCV potency, two novel types of quercetin analogues, 7-O-arylmethylquercetins and quercetin-3-O-benzoic acid esters, were designed, synthesized and evaluated for their anti-HCV properties in cell-based assays. Among the 38 newly synthesized compounds, 7-O-substituted derivative 3i and 3-O-substituted derivative 4f were found to be the most active in the corresponding series (EC50 = 3.8 μM and 9.0 μΜ, respectively). Docking studies suggested that the quercetin analogues are capable of establishing key coordination with the two magnesium ions as well as interactions with residues at the active site of HCV NS5B.

  1. 3-Amido-3-aryl-piperidines: A Novel Class of Potent, Selective, and Orally Active GlyT1 Inhibitors.

    PubMed

    Pinard, Emmanuel; Alberati, Daniela; Alvarez-Sanchez, Ruben; Brom, Virginie; Burner, Serge; Fischer, Holger; Hauser, Nicole; Kolczewski, Sabine; Lengyel, Judith; Mory, Roland; Saladin, Christian; Schulz-Gasch, Tanja; Stalder, Henri

    2014-04-10

    3-Amido-3-aryl-piperidines were discovered as a novel structural class of GlyT1 inhibitors. The structure-activity relationship, which was developed, led to the identification of highly potent compounds exhibiting excellent selectivity against the GlyT2 isoform, drug-like properties, and in vivo activity after oral administration.

  2. 3-Amido-3-aryl-piperidines: A Novel Class of Potent, Selective, and Orally Active GlyT1 Inhibitors

    PubMed Central

    2014-01-01

    3-Amido-3-aryl-piperidines were discovered as a novel structural class of GlyT1 inhibitors. The structure–activity relationship, which was developed, led to the identification of highly potent compounds exhibiting excellent selectivity against the GlyT2 isoform, drug-like properties, and in vivo activity after oral administration. PMID:24900853

  3. Polyinosinic:polycytidylic acid is a potent activator of endothelial cells.

    PubMed Central

    Doukas, J.; Cutler, A. H.; Mordes, J. P.

    1994-01-01

    Polyinosinic:polycytidylic acid (poly I:C) is a synthetic double-stranded polyribonucleotide that elicits immune responses analogous to those observed during viral infection. It is also known to modulate the expression of certain autoimmune disorders including diabetes mellitus in the BB rat and NOD mouse. The mechanism underlying these immunomodulatory effects is not known, but it could involve activation of vascular endothelium. We now report that parenteral poly I:C induces rat pancreatic endothelium to hyperexpress intercellular adhesion molecule 1 (CD54). This is accompanied by a perivascular recruitment of mononuclear cells to the exocrine pancreas. Corollary in vitro studies demonstrated that poly I:C is a potent activator of both rat and human endothelial cells in culture. It upregulates endothelial expression of several leukocyte adhesion molecules, stimulates the release of interleukin-6 and interleukin-8, and antagonizes interferon-gamma induction of major histocompatibility complex class II expression. We conclude that poly I:C activates endothelial cells to express surface molecules and cytokines in a pattern classically associated with leukocyte recruitment. These effects may in part contribute to the immunomodulatory effects of poly I:C in animal models of autoimmunity. Images Figure 1 Figure 2 PMID:7518192

  4. Novel merosesquiterpene exerts a potent antitumor activity against breast cancer cells in vitro and in vivo.

    PubMed

    Carrasco, Esther; Álvarez, Pablo Juan; Melguizo, Consolación; Prados, José; Álvarez-Manzaneda, Enrique; Chahboun, Rachid; Messouri, Ibtissam; Vázquez-Vázquez, María Isabel; Aránega, Antonia; Rodríguez-Serrano, Fernando

    2014-05-22

    This article describes the antitumor properties of a new family of merosesquiterpenes, which were synthesized by Diels-Alder cycloaddition of the labdane diene trans-communic acid, highly abundant in Cupressus sempervirens, or its methyl ester, with the appropriate dienophile. These compounds demonstrated potent cytotoxic activity in vitro against human breast, colon, and lung tumor cells. We highlight the elevated activity (IC50: 0.35 ± 0.10 μM) and specificity (TI: 9) of compound 13 against the MCF-7 line, which corresponds to the most prevalent breast cancer cell subtype, luminal A. It was found that compound 13 exerts its anti-tumor action by inducing oxidative stress, arresting the cell cycle in stages G0-G1, and activating apoptosis, which are all associated with low cyclin D1 regulation, pRb hypophosphorylation, increased expression of p27 and p53, and poly (ADP-ribose) polymerase (PARP) fractioning. Epithelial-mesenchymal transition, a phenomenon associated with metastasis promotion and a worsened prognosis also appeared to be inhibited by compound 13. In addition, it markedly reduced tumor development in immunocompetent C57BL/6 mice with allografts of E0771 mouse breast tumor cells (luminal A subtype). According to these findings, this new family of compounds, especially compound 13, may be highly useful in the treatment of human breast cancer.

  5. Nifuroxazide exerts potent anti-tumor and anti-metastasis activity in melanoma

    PubMed Central

    Zhu, Yongxia; Ye, Tinghong; Yu, Xi; Lei, Qian; Yang, Fangfang; Xia, Yong; Song, Xuejiao; Liu, Li; Deng, Hongxia; Gao, Tiantao; Peng, Cuiting; Zuo, Weiqiong; Xiong, Ying; Zhang, Lidan; Wang, Ningyu; Zhao, Lifeng; Xie, Yongmei; Yu, Luoting; Wei, Yuquan

    2016-01-01

    Melanoma is a highly malignant neoplasm of melanocytes with considerable metastatic potential and drug resistance, explaining the need for new candidates that inhibit tumor growth and metastasis. The signal transducer and activator of the transcription 3 (Stat3) signaling pathway plays an important role in melanoma and has been validated as promising anticancer target for melanoma therapy. In this study, nifuroxazide, an antidiarrheal agent identified as an inhibitor of Stat3, was evaluated for its anti-melanoma activity in vitro and in vivo. It had potent anti-proliferative activity against various melanoma cell lines and could induce G2/M phase arrest and cell apoptosis. Moreover, nifuroxazide markedly impaired melanoma cell migration and invasion by down-regulating phosphorylated-Src, phosphorylated-FAK, and expression of matrix metalloproteinase (MMP) -2, MMP-9 and vimentin. It also significantly inhibited tumor growth without obvious side effects in the A375-bearing mice model by inducing apoptosis and reducing cell proliferation and metastasis. Notably, nifuroxazide significantly inhibited pulmonary metastases, which might be associated with the decrease of myeloid-derived suppressor cells (MDSCs). These findings suggested that nifuroxazide might be a potential agent for inhibiting the growth and metastasis of melanoma. PMID:26830149

  6. Nifuroxazide exerts potent anti-tumor and anti-metastasis activity in melanoma.

    PubMed

    Zhu, Yongxia; Ye, Tinghong; Yu, Xi; Lei, Qian; Yang, Fangfang; Xia, Yong; Song, Xuejiao; Liu, Li; Deng, Hongxia; Gao, Tiantao; Peng, Cuiting; Zuo, Weiqiong; Xiong, Ying; Zhang, Lidan; Wang, Ningyu; Zhao, Lifeng; Xie, Yongmei; Yu, Luoting; Wei, Yuquan

    2016-01-01

    Melanoma is a highly malignant neoplasm of melanocytes with considerable metastatic potential and drug resistance, explaining the need for new candidates that inhibit tumor growth and metastasis. The signal transducer and activator of the transcription 3 (Stat3) signaling pathway plays an important role in melanoma and has been validated as promising anticancer target for melanoma therapy. In this study, nifuroxazide, an antidiarrheal agent identified as an inhibitor of Stat3, was evaluated for its anti-melanoma activity in vitro and in vivo. It had potent anti-proliferative activity against various melanoma cell lines and could induce G2/M phase arrest and cell apoptosis. Moreover, nifuroxazide markedly impaired melanoma cell migration and invasion by down-regulating phosphorylated-Src, phosphorylated-FAK, and expression of matrix metalloproteinase (MMP) -2, MMP-9 and vimentin. It also significantly inhibited tumor growth without obvious side effects in the A375-bearing mice model by inducing apoptosis and reducing cell proliferation and metastasis. Notably, nifuroxazide significantly inhibited pulmonary metastases, which might be associated with the decrease of myeloid-derived suppressor cells (MDSCs). These findings suggested that nifuroxazide might be a potential agent for inhibiting the growth and metastasis of melanoma. PMID:26830149

  7. Potent Cardioprotective Effect of the 4-Anilinoquinazoline Derivative PD153035: Involvement of Mitochondrial KATP Channel Activation

    PubMed Central

    Rocco, Silvana A.; Cerqueira, Fernanda M.; Caldeira da Silva, Camille C.; Rittner, Roberto; Kowaltowski, Alicia J.; Vercesi, Anibal E.; Franchini, Kleber G.; Castilho, Roger F.

    2010-01-01

    Background The aim of the present study was to evaluate the protective effects of the 4-anilinoquinazoline derivative PD153035 on cardiac ischemia/reperfusion and mitochondrial function. Methodology/Principal Findings Perfused rat hearts and cardiac HL-1 cells were used to determine cardioprotective effects of PD153035. Isolated rat heart mitochondria were studied to uncover mechanisms of cardioprotection. Nanomolar doses of PD153035 strongly protect against heart and cardiomyocyte damage induced by ischemia/reperfusion and cyanide/aglycemia. PD153035 did not alter oxidative phosphorylation, nor directly prevent Ca2+ induced mitochondrial membrane permeability transition. The protective effect of PD153035 on HL-1 cells was also independent of AKT phosphorylation state. Interestingly, PD153035 activated K+ transport in isolated mitochondria, in a manner prevented by ATP and 5-hydroxydecanoate, inhibitors of mitochondrial ATP-sensitive K+ channels (mitoKATP). 5-Hydroxydecanoate also inhibited the cardioprotective effect of PD153035 in cardiac HL-1 cells, demonstrating that this protection is dependent on mitoKATP activation. Conclusions/Significance We conclude that PD153035 is a potent cardioprotective compound and acts in a mechanism involving mitoKATP activation. PMID:20498724

  8. Structure-activity relationships of 1,3-benzoxazole-4-carbonitriles as novel antifungal agents with potent in vivo efficacy.

    PubMed

    Kuroyanagi, Jun-ichi; Kanai, Kazuo; Horiuchi, Takao; Takeshita, Hiroshi; Kobayashi, Shozo; Achiwa, Issei; Yoshida, Kumi; Nakamura, Koichi; Kawakami, Katsuhiro

    2011-01-01

    A series of 1,3-benzoxazole-4-carbonitriles was synthesized and evaluated for its antifungal activity, solubility, and metabolic stability. Among those compounds, 4-cyano-N,N,5-trimethyl-7-[(3S)-3-methyl-3-(methylamino)pyrrolidin-1-yl]-6-phenyl-1,3-benzoxazole-2-carboxamide (16b) exhibited potent in vitro activity against Candida species, higher water solubility, and improved metabolic stability compared to lead compound 1. Compound 16b showed potent in vivo efficacy against mice Candida infection models and good bioavailability in rats.

  9. Unique intracellular activation of the potent anti-human immunodeficiency virus agent 1592U89.

    PubMed Central

    Faletto, M B; Miller, W H; Garvey, E P; St Clair, M H; Daluge, S M; Good, S S

    1997-01-01

    The anabolism of 1592U89, (-)-(1S,4R)-4-[2-amino-6-(cyclopropylamino)-9H-purin-9-yl]-2-cyclo pentene-1-methanol, a selective inhibitor of human immunodeficiency virus (HIV), was characterized in human T-lymphoblastoid CD4+ CEM cells. 1592U89 was ultimately anabolized to the triphosphate (TP) of the guanine analog (-)-carbovir (CBV), a potent inhibitor of HIV reverse transcriptase. However, less than 2% of intracellular 1592U89 was converted to CBV, an amount insufficient to account for the CBV-TP levels observed. 1592U89 was anabolized to its 5'-monophosphate (MP) by the recently characterized enzyme adenosine phosphotransferase, but neither its diphosphate (DP) nor its TP was detected. The MP, DP, and TP of CBV were found in cells incubated with either 1592U89 or CBV, with CBV-TP being the major phosphorylated species. We confirmed that CBV is phosphorylated by 5'-nucleotidase and that mycophenolic acid increased the formation of CBV-TP from CBV 75-fold. However, mycophenolic acid did not stimulate 1592U89 anabolism to CBV-TP. The adenosine deaminase inhibitor erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA) did not inhibit CBV-TP formation from CBV or 1592U89, whereas the adenylate deaminase inhibitor 2'-deoxycoformycin selectively inhibited 1592U89 anabolism to CBV-TP and reversed the antiviral activity of 1592U89. 1592U89-MP was not a substrate for adenylate deaminase but was a substrate for a distinct cytosolic deaminase that was inhibited by 2'-deoxycoformycin-5'-MP. Thus, 1592U89 is phosphorylated by adenosine phosphotransferase to 1592U89-MP, which is converted by a novel cytosolic enzyme to CBV-MP. CBV-MP is then further phosphorylated to CBV-TP by cellular kinases. This unique activation pathway enables 1592U89 to overcome the pharmacokinetic and toxicological deficiencies of CBV while maintaining potent and selective anti-HIV activity. PMID:9145876

  10. Collybolide is a novel biased agonist of κ-opioid receptors with potent antipruritic activity.

    PubMed

    Gupta, Achla; Gomes, Ivone; Bobeck, Erin N; Fakira, Amanda K; Massaro, Nicholas P; Sharma, Indrajeet; Cavé, Adrien; Hamm, Heidi E; Parello, Joseph; Devi, Lakshmi A

    2016-05-24

    Among the opioid receptors, the κ-opioid receptor (κOR) has been gaining considerable attention as a potential therapeutic target for the treatment of complex CNS disorders including depression, visceral pain, and cocaine addiction. With an interest in discovering novel ligands targeting κOR, we searched natural products for unusual scaffolds and identified collybolide (Colly), a nonnitrogenous sesquiterpene from the mushroom Collybia maculata. This compound has a furyl-δ-lactone core similar to that of Salvinorin A (Sal A), another natural product from the plant Salvia divinorum Characterization of the molecular pharmacological properties reveals that Colly, like Sal A, is a highly potent and selective κOR agonist. However, the two compounds differ in certain signaling and behavioral properties. Colly exhibits 10- to 50-fold higher potency in activating the mitogen-activated protein kinase pathway compared with Sal A. Taken with the fact that the two compounds are equipotent for inhibiting adenylyl cyclase activity, these results suggest that Colly behaves as a biased agonist of κOR. Behavioral studies also support the biased agonistic activity of Colly in that it exhibits ∼10-fold higher potency in blocking non-histamine-mediated itch compared with Sal A, and this difference is not seen in pain attenuation by these two compounds. These results represent a rare example of functional selectivity by two natural products that act on the same receptor. The biased agonistic activity, along with an easily modifiable structure compared with Sal A, makes Colly an ideal candidate for the development of novel therapeutics targeting κOR with reduced side effects. PMID:27162327

  11. Potent inhibition of human neutrophil activations by bractelactone, a novel chalcone from Fissistigma bracteolatum

    SciTech Connect

    Wu, Yang-Chang; Sureshbabu, Munisamy; Fang, Yao-Ching; Wu, Yi-Hsiu; Lan, Yu-Hsuan; Chang, Fang-Rong; Chang, Ya-Wen; Hwang, Tsong-Long

    2013-02-01

    Fissistigma bracteolatum is widely used in traditional medicine to treat inflammatory diseases. However, its active components and mechanisms of action remain unclear. In this study, (3Z)-6,7-dihydroxy-4-methoxy-3-(phenylmethylidene)-5-(3-phenylpropanoyl) -1-benzofuran-2(3H) (bractelactone), a novel chalcone from F. bracteolatum, showed potent inhibitory effects against superoxide anion (O{sub 2}{sup ·−}) production, elastase release, and CD11b expression in formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP)-induced human neutrophils. However, bractelactone showed only weak inhibition of phorbol myristate acetate-caused O{sub 2}{sup ·−} production. The peak cytosolic calcium concentration ([Ca{sup 2+}]{sub i}) was unaltered by bractelactone in FMLP-induced neutrophils, but the decay time of [Ca{sup 2+}]{sub i} was significantly shortened. In a calcium-free solution, changes in [Ca{sup 2+}]{sub i} caused by the addition of extracellular Ca{sup 2+} were inhibited by bractelactone in FMLP-activated cells. In addition, bractelactone did not alter the phosphorylation of p38 MAPK, ERK, JNK, or AKT or the concentration of cAMP. These results suggest that bractelactone selectively inhibits store-operated calcium entry (SOCE). In agreement with this concept, bractelactone suppressed sustained [Ca{sup 2+}]{sub i} changes in thapsigargin-activated neutrophils. Furthermore, bractelactone did not alter FMLP-induced formation of inositol 1,4,5-triphosphate. Taken together, our results demonstrate that the anti-inflammatory effects of bractelactone, an active ingredient of F. bracteolatum, in human neutrophils are through the selective inhibition of SOCE. Highlights: ► Bractelactone isolated from Fissistigma bracteolatum. ► Bractelactone inhibited FMLP-induced human neutrophil activations. ► Bractelactone had no effect on IP3 formation. ► Bractelactone did not alter MAPKs, AKT, and cAMP pathways. ► Bractelactone inhibited store-operated calcium entry.

  12. Biflavonoids of Dacrydium balansae with potent inhibitory activity on dengue 2 NS5 polymerase.

    PubMed

    Coulerie, Paul; Eydoux, Cécilia; Hnawia, Edouard; Stuhl, Laetitia; Maciuk, Alexandre; Lebouvier, Nicolas; Canard, Bruno; Figadère, Bruno; Guillemot, Jean-Claude; Nour, Mohammed

    2012-05-01

    In order to find new molecules for antiviral drug design, we screened 102 ethyl acetate extracts from New-Caledonian flora for antiviral activity against the dengue 2 virus RNA-dependant RNA polymerase (DV-NS5 RdRp). The leaf extract of Dacrydium balansae, which strongly inhibited the DV-NS5, was submitted to bioguided fractionation. Four biflavonoids ( 1- 4), three sterols ( 5- 7), and two stilbene derivatives ( 8- 9) were identified and evaluated for their antiviral potential on the DV-NS5 RdRp. Biflavonoids appeared to be potent inhibitors of DV-NS5 RdRp with IC (50)s between 0.26 and 3.12 µM. Inhibitory activity evaluations against the RNA polymerase from other Flaviviridae viruses allowed us to conclude that these compounds are specific inhibitors of the DV RNA polymerase. The strongest inhibitions were observed with hinokiflavone ( 4), but podocarpusflavone A ( 2) is the strongest noncytotoxic inhibitor of the DV-NS5 and it also displayed polymerase inhibitory activity in a DV replicon. A preliminary structure-activity relationship study (SARs) revealed the necessity of the biflavonoid skeleton, the influence of number and position of methoxylations, and the importance of a free rotation of the linkage between the two apigenin monomers of the biflavonoids. To the best of our knowledge, podocarpusflavone A ( 2) is the strongest noncytotoxic non-nucleotide molecule exhibiting a specific inhibitory activity against the RNA polymerase domain of DV-NS5 and thus is promising for chemotherapy development against dengue fever. PMID:22411725

  13. Berberine is a potent agonist of peroxisome proliferator activated receptor alpha.

    PubMed

    Yu, Huarong; Li, Changqing; Yang, Junqing; Zhang, Tao; Zhou, Qixin

    2016-01-01

    Although berberine has hypolipidemic effects with a high affinity to nuclear proteins, the underlying molecular mechanism for this effect remains unclear. Here, we determine whether berberine is an agonist of peroxisome proliferator-activated receptor alpha (PPARalpha), with a lipid-lowering effect. The cell-based reporter gene analysis showed that berberine selectively activates PPARalpha (EC50 =0.58 mM, Emax =102.4). The radioligand binding assay shows that berberine binds directly to the ligand-binding domain of PPARalpha (Ki=0.73 mM) with similar affinity to fenofibrate. The mRNA and protein levels of CPT-Ialpha gene from HepG2 cells and hyperlipidemic rat liver are remarkably up-regulated by berberine, and this effect can be blocked by MK886, a non-competitive antagonist of PPARalpha. A comparison assay in which berberine and fenofibrate were used to treat hyperlipidaemic rats for three months shows that these drugs produce similar lipid-lowering effects, except that berberine increases high-density lipoprotein cholesterol more effectively than fenofibrate. These findings provide the first evidence that berberine is a potent agonist of PPARalpha and seems to be superior to fenofibrate for treating hyperlipidemia. PMID:27100490

  14. Structure-Based Tetravalent Zanamivir with Potent Inhibitory Activity against Drug-Resistant Influenza Viruses.

    PubMed

    Fu, Lifeng; Bi, Yuhai; Wu, Yan; Zhang, Shanshan; Qi, Jianxun; Li, Yan; Lu, Xuancheng; Zhang, Zhenning; Lv, Xun; Yan, Jinghua; Gao, George F; Li, Xuebing

    2016-07-14

    Zanamivir and oseltamivir are principal influenza antiviral drugs that target viral neuraminidase (NA), but resistant viruses containing mutant NAs with diminished drug affinity are increasingly emerging. Using the structural knowledge of both drug-binding sites and their spatial arrangement on the homotetrameric NA, we have developed a tetravalent zanamivir (TZ) molecule that exhibited marked increases in NA binding affinity, inhibition of NA enzyme activity, and in vitro plus in vivo antiviral efficacy over zanamivir. TZ functioned against both human seasonal H3N2 and avian H7N9 viruses, including drug-resistant mutants. Crystal structure of a resistant N9 NA in complex with TZ explained the function, which showed that four zanamivir residues simultaneously bound to all four monomers of NA. The design method of TZ described in this study may be useful to develop drugs or ligands that target proteins with multiple binding sites. The potent anti-influenza activity of TZ makes it attractive for further development. PMID:27341624

  15. Characterization of DicB by partially masking its potent inhibitory activity of cell division.

    PubMed

    Yang, Shaoyuan; Pei, Hairun; Zhang, Xiaoying; Wei, Qiang; Zhu, Jia; Zheng, Jimin; Jia, Zongchao

    2016-07-01

    DicB, a protein encoded by the Kim (Qin) prophage in Escherichia coli, inhibits cell division through interaction with MinC. Thus far, characterization of DicB has been severely hampered owing to its potent activity which ceases cell division and leads to cell death. In this work, through fusing maltose-binding protein to the N-terminus of DicB (MBP-DicB), we successfully expressed and purified recombinant DicB that enabled in vitro analysis for the first time. More importantly, taking advantage of the reduced inhibitory activity of MBP-DicB, we were able to study its effects on cell growth and morphology. Inhibition of cell growth by MBP-DicB was systematically evaluated using various DicB constructs, and their corresponding effects on cell morphology were also investigated. Our results revealed that the N-terminal segment of DicB plays an essential functional role, in contrast to its C-terminal tail. The N-terminus of DicB is of critical importance as even the first amino acid (following the initial Met) could not be removed, although it could be mutated. This study provides the first glimpse of the molecular determinants underlying DicB's function. PMID:27466443

  16. Mirror-image organometallic osmium arene iminopyridine halido complexes exhibit similar potent anticancer activity.

    PubMed

    Fu, Ying; Soni, Rina; Romero, María J; Pizarro, Ana M; Salassa, Luca; Clarkson, Guy J; Hearn, Jessica M; Habtemariam, Abraha; Wills, Martin; Sadler, Peter J

    2013-11-01

    Four chiral Os(II) arene anticancer complexes have been isolated by fractional crystallization. The two iodido complexes, (S(Os),S(C))-[Os(η(6)-p-cym)(ImpyMe)I]PF6 (complex 2, (S)-ImpyMe: N-(2-pyridylmethylene)-(S)-1-phenylethylamine) and (R(Os),R(C))-[Os(η(6)-p-cym)(ImpyMe)I]PF6 (complex 4, (R)-ImpyMe: N-(2-pyridylmethylene)-(R)-1-phenylethylamine), showed higher anticancer activity (lower IC50 values) towards A2780 human ovarian cancer cells than cisplatin and were more active than the two chlorido derivatives, (S(Os),S(C))-[Os(η(6)-p-cym)(ImpyMe)Cl]PF6, 1, and (R(Os),R(C))-[Os(η(6)-p-cym)(ImpyMe)Cl]PF6, 3. The two iodido complexes were evaluated in the National Cancer Institute 60-cell-line screen, by using the COMPARE algorithm. This showed that the two potent iodido complexes, 2 (NSC: D-758116/1) and 4 (NSC: D-758118/1), share surprisingly similar cancer cell selectivity patterns with the anti-microtubule drug, vinblastine sulfate. However, no direct effect on tubulin polymerization was found for 2 and 4, an observation that appears to indicate a novel mechanism of action. In addition, complexes 2 and 4 demonstrated potential as transfer-hydrogenation catalysts for imine reduction.

  17. LY303366 exhibits rapid and potent fungicidal activity in flow cytometric assays of yeast viability.

    PubMed

    Green, L J; Marder, P; Mann, L L; Chio, L C; Current, W L

    1999-04-01

    LY303366 is a semisynthetic analog of the antifungal lipopeptide echinocandin B that inhibits (1,3)-beta-D-glucan synthase and exhibits efficacy in animal models of human fungal infections. In this study, we utilized flow cytometric analysis of propidium iodide uptake, single-cell sorting, and standard microbiological plating methods to study the antifungal effect of LY303366 on Saccharomyces cerevisiae and Candida albicans. Our data indicate that an initial 5-min pulse treatment with LY303366 caused yeasts to take up propidium iodide and lose their ability to grow. Amphotericin B and cilofungin required longer exposure periods (30 and 180 min, respectively) and higher concentrations to elicit these fungicidal effects. These two measurements of fungicidal activity by LY303366 were highly correlated (r > 0.99) in concentration response and time course experiments. As further validation, LY303366-treated yeasts that stained with propidium iodide were unable to grow in single-cell-sorted cultures. Our data indicate that LY303366 is potent and rapidly fungicidal for actively growing yeasts. The potency and rapid action of this new fungicidal compound suggest that LY303366 may be useful for antifungal therapy. PMID:10103187

  18. Putting copper into action: copper-impregnated products with potent biocidal activities.

    PubMed

    Borkow, Gadi; Gabbay, Jeffrey

    2004-11-01

    Copper ions, either alone or in copper complexes, have been used for centuries to disinfect liquids, solids, and human tissue. Today copper is used as a water purifier, algaecide, fungicide, nematocide, molluscicide, and antibacterial and antifouling agent. Copper also displays potent antiviral activity. We hypothesized that introducing copper into clothing, bedding, and other articles would provide them with biocidal properties. A durable platform technology has been developed that introduces copper into cotton fibers, latex, and other polymeric materials. This study demonstrates the broad-spectrum antimicrobial (antibacterial, antiviral, antifungal) and antimite activities of copper-impregnated fibers and polyester products. This technology enabled the production of antiviral gloves and filters (which deactivate HIV-1 and other viruses), antibacterial self-sterilizing fabrics (which kill antibiotic-resistant bacteria, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci), antifungal socks (which alleviate symptoms of athlete's foot), and anti-dust mite mattress covers (which reduce mite-related allergies). These products did not have skin-sensitizing properties, as determined by guine pig maximization and rabbit skin irritation tests. Our study demonstrates the potential use of copper in new applications. These applications address medical issues of the greatest importance, such as viral transmissions; nosocomial, or healthcare-associated, infections; and the spread of antibiotic-resistant bacteria. PMID:15345689

  19. Characterization of DicB by partially masking its potent inhibitory activity of cell division

    PubMed Central

    Yang, Shaoyuan; Pei, Hairun; Zhang, Xiaoying; Wei, Qiang; Zhu, Jia; Zheng, Jimin; Jia, Zongchao

    2016-01-01

    DicB, a protein encoded by the Kim (Qin) prophage in Escherichia coli, inhibits cell division through interaction with MinC. Thus far, characterization of DicB has been severely hampered owing to its potent activity which ceases cell division and leads to cell death. In this work, through fusing maltose-binding protein to the N-terminus of DicB (MBP–DicB), we successfully expressed and purified recombinant DicB that enabled in vitro analysis for the first time. More importantly, taking advantage of the reduced inhibitory activity of MBP–DicB, we were able to study its effects on cell growth and morphology. Inhibition of cell growth by MBP–DicB was systematically evaluated using various DicB constructs, and their corresponding effects on cell morphology were also investigated. Our results revealed that the N-terminal segment of DicB plays an essential functional role, in contrast to its C-terminal tail. The N-terminus of DicB is of critical importance as even the first amino acid (following the initial Met) could not be removed, although it could be mutated. This study provides the first glimpse of the molecular determinants underlying DicB's function. PMID:27466443

  20. Potent Plasmodium falciparum Gametocytocidal Activity of Diaminonaphthoquinones, Lead Antimalarial Chemotypes Identified in an Antimalarial Compound Screen

    PubMed Central

    Tanaka, Takeshi Q; Guiguemde, W. Armand; Barnett, David S.; Maron, Maxim I.; Min, Jaeki; Connelly, Michele C.; Suryadevara, Praveen Kumar; Guy, R. Kiplin

    2014-01-01

    Forty percent of the world's population is threatened by malaria, which is caused by Plasmodium parasites and results in an estimated 200 million clinical cases and 650,000 deaths each year. Drug resistance has been reported for all commonly used antimalarials and has prompted screens to identify new drug candidates. However, many of these new candidates have not been evaluated against the parasite stage responsible for transmission, gametocytes. If Plasmodium falciparum gametocytes are not eliminated, patients continue to spread malaria for weeks after asexual parasite clearance. Asymptomatic individuals can also harbor gametocyte burdens sufficient for transmission, and a safe, effective gametocytocidal agent could also be used in community-wide malaria control programs. Here, we identify 15 small molecules with nanomolar activity against late-stage gametocytes. Fourteen are diaminonaphthoquinones (DANQs), and one is a 2-imino-benzo[d]imidazole (IBI). One of the DANQs identified, SJ000030570, is a lead antimalarial candidate. In contrast, 94% of the 650 compounds tested are inactive against late-stage gametocytes. Consistent with the ineffectiveness of most approved antimalarials against gametocytes, of the 19 novel compounds with activity against known anti-asexual-stage targets, only 3 had any strong effect on gametocyte viability. These data demonstrate the distinct biology of the transmission stages and emphasize the importance of screening for gametocytocidal activity. The potent gametocytocidal activity of DANQ and IBI coupled with their efficacy against asexual parasites provides leads for the development of antimalarials with the potential to prevent both the symptoms and the spread of malaria. PMID:25512421

  1. Potent Plasmodium falciparum gametocytocidal activity of diaminonaphthoquinones, lead antimalarial chemotypes identified in an antimalarial compound screen.

    PubMed

    Tanaka, Takeshi Q; Guiguemde, W Armand; Barnett, David S; Maron, Maxim I; Min, Jaeki; Connelly, Michele C; Suryadevara, Praveen Kumar; Guy, R Kiplin; Williamson, Kim C

    2015-03-01

    Forty percent of the world's population is threatened by malaria, which is caused by Plasmodium parasites and results in an estimated 200 million clinical cases and 650,000 deaths each year. Drug resistance has been reported for all commonly used antimalarials and has prompted screens to identify new drug candidates. However, many of these new candidates have not been evaluated against the parasite stage responsible for transmission, gametocytes. If Plasmodium falciparum gametocytes are not eliminated, patients continue to spread malaria for weeks after asexual parasite clearance. Asymptomatic individuals can also harbor gametocyte burdens sufficient for transmission, and a safe, effective gametocytocidal agent could also be used in community-wide malaria control programs. Here, we identify 15 small molecules with nanomolar activity against late-stage gametocytes. Fourteen are diaminonaphthoquinones (DANQs), and one is a 2-imino-benzo[d]imidazole (IBI). One of the DANQs identified, SJ000030570, is a lead antimalarial candidate. In contrast, 94% of the 650 compounds tested are inactive against late-stage gametocytes. Consistent with the ineffectiveness of most approved antimalarials against gametocytes, of the 19 novel compounds with activity against known anti-asexual-stage targets, only 3 had any strong effect on gametocyte viability. These data demonstrate the distinct biology of the transmission stages and emphasize the importance of screening for gametocytocidal activity. The potent gametocytocidal activity of DANQ and IBI coupled with their efficacy against asexual parasites provides leads for the development of antimalarials with the potential to prevent both the symptoms and the spread of malaria. PMID:25512421

  2. Chemical Evidence for Potent Xanthine Oxidase Inhibitory Activity of Ethyl Acetate Extract of Citrus aurantium L. Dried Immature Fruits.

    PubMed

    Liu, Kun; Wang, Wei; Guo, Bing-Hua; Gao, Hua; Liu, Yang; Liu, Xiao-Hong; Yao, Hui-Li; Cheng, Kun

    2016-03-02

    Xanthine oxidase is a key enzyme which can catalyze hypoxanthine and xanthine to uric acid causing hyperuricemia in humans. Xanthine oxidase inhibitory activities of 24 organic extracts of four species belonging to Citrus genus of the family Rutaceae were assayed in vitro. Since the ethyl acetate extract of C. aurantium dried immature fruits showed the highest xanthine oxidase inhibitory activity, chemical evidence for the potent inhibitory activity was clarified on the basis of structure identification of the active constituents. Five flavanones and two polymethoxyflavones were isolated and evaluated for inhibitory activity against xanthine oxidase in vitro. Of the compounds, hesperetin showed more potent inhibitory activity with an IC50 value of 16.48 μM. For the first time, this study provides a rational basis for the use of C. aurantium dried immature fruits against hyperuricemia.

  3. Discovery of a novel, potent and orally active series of gamma-lactams as selective NK1 antagonists.

    PubMed

    Paliwal, Sunil; Reichard, Gregory A; Shah, Sapna; Wrobleski, Michelle Laci; Wang, Cheng; Stengone, Carmine; Tsui, Hon-Chung; Xiao, Dong; Duffy, Ruth A; Lachowicz, Jean E; Nomeir, Amin A; Varty, Geoffrey B; Shih, Neng-Yang

    2008-07-15

    Strategic replacement of the nitrogen of the lead compound 1 in the original cyclic urea series with a carbon resulted in the discovery of a novel, potent and orally more efficacious gamma-lactam series of selective NK(1) antagonists. Optimization of the lactam series culminated in the identification of compounds with high binding affinity and excellent oral CNS activity.

  4. In vitro activity of a new carbapenem antibiotic, BO-2727, with potent antipseudomonal activity.

    PubMed Central

    Nakagawa, S; Hashizume, T; Matsuda, K; Sanada, M; Okamoto, O; Fukatsu, H; Tanaka, N

    1993-01-01

    BO-2727, a new 1-beta-methyl-carbapenem, was active at concentrations of 6.25 micrograms/ml or less against gram-positive and gram-negative bacteria, including some imipenem- and/or meropenem-resistant (MICs, > or = 12.5 micrograms/ml) Pseudomonas aeruginosa strains, against which it proved generally fourfold more active than imipenem and meropenem. BO-2727's antipseudomonal activity and its broad spectrum merit further investigation for clinical use by itself, since it was stable in the presence of renal dehydropeptidase I. PMID:8109950

  5. Novel Synthesis of Kanamycin Conjugated Gold Nanoparticles with Potent Antibacterial Activity

    PubMed Central

    Payne, Jason N.; Waghwani, Hitesh K.; Connor, Michael G.; Hamilton, William; Tockstein, Sarah; Moolani, Harsh; Chavda, Fenil; Badwaik, Vivek; Lawrenz, Matthew B.; Dakshinamurthy, Rajalingam

    2016-01-01

    With a sharp increase in the cases of multi-drug resistant (MDR) bacteria all over the world, there is a huge demand to develop a new generation of antibiotic agents to fight them. As an alternative to the traditional drug discovery route, we have designed an effective antibacterial agent by modifying an existing commercial antibiotic, kanamycin, conjugated on the surface of gold nanoparticles (AuNPs). In this study, we report a single-step synthesis of kanamycin-capped AuNPs (Kan-AuNPs) utilizing the combined reducing and capping properties of kanamycin. While Kan-AuNPs have increased toxicity to a primate cell line (Vero 76), antibacterial assays showed dose-dependent broad spectrum activity of Kan-AuNPs against both Gram-positive and Gram-negative bacteria, including Kanamycin resistant bacteria. Further, a significant reduction in the minimum inhibitory concentration (MIC) of Kan-AuNPs was observed when compared to free kanamycin against all the bacterial strains tested. Mechanistic studies using transmission electron microscopy and fluorescence microscopy indicated that at least part of Kan-AuNPs increased efficacy may be through disrupting the bacterial envelope, resulting in the leakage of cytoplasmic content and the death of bacterial cells. Results of this study provide critical information about a novel method for the development of antibiotic capped AuNPs as potent next-generation antibacterial agents. PMID:27330535

  6. Identification and Structure-Activity Relationships of Diarylhydrazides as Novel Potent and Selective Human Enterovirus Inhibitors.

    PubMed

    Han, Xin; Sun, Ningyuan; Wu, Haoming; Guo, Deyin; Tien, Po; Dong, Chune; Wu, Shuwen; Zhou, Hai-Bing

    2016-03-10

    Enterovirus 71 (EV71) plays an important role in hand-foot-and-mouth disease. In this study, a series of diarylhydrazide analogues was synthesized, and the systematic exploration of SAR led to potent enterovirus inhibitors, of which compound 15 exhibits significant improvements in inhibition potency with an EC50 value of 0.02 μM against EV71. It is very interesting that this class of diarylhydrazides exhibits activities against a series of human enteroviruses at the picomolar level, including EV71 and Coxsackieviruses B1 (CVB1), CVB2, CVB3, CVB4, CVB5, and CVB6 (EC50 as low as 0.5 nM). Compared with the reference antienterovirus drug 1 (enviroxime) and known inhibitor 5 (WIN 51711), the four highly selective compounds 15, 27, 41 and 47 inhibited EV71 replication with EC50 values of 0.17-0.02 μM and SI values in a range of 978.4-12338. A preliminary mechanistic study indicated that VP1 might be the target site for this type of compound.

  7. Green synthesis of silk sericin-capped silver nanoparticles and their potent anti-bacterial activity

    NASA Astrophysics Data System (ADS)

    Aramwit, Pornanong; Bang, Nipaporn; Ratanavaraporn, Juthamas; Ekgasit, Sanong

    2014-02-01

    In this study, a `green chemistry' approach was introduced to synthesize silk sericin (SS)-capped silver nanoparticles (AgNPs) under an alkaline condition (pH 11) using SS as a reducing and stabilizing agent instead of toxic chemicals. The SS-capped AgNPs were successfully synthesized at various concentrations of SS and AgNO3, but the yields were different. A higher yield of SS-capped AgNPs was obtained when the concentrations of SS and AgNO3 were increased. The SS-capped AgNPs showed a round shape and uniform size with diameter at around 48 to 117 nm. The Fourier transform infrared (FT-IR) spectroscopy result proved that the carboxylate groups obtained from alkaline degradation of SS would be a reducing agent for the generation of AgNPs while COO- and NH2 + groups stabilized the AgNPs and prevented their precipitation or aggregation. Furthermore, the SS-capped AgNPs showed potent anti-bacterial activity against various gram-positive bacteria (minimal inhibitory concentration (MIC) 0.008 mM) and gram-negative bacteria (MIC ranging from 0.001 to 0.004 mM). Therefore, the SS-capped AgNPs would be a safe candidate for anti-bacterial applications.

  8. Green synthesis of silk sericin-capped silver nanoparticles and their potent anti-bacterial activity

    PubMed Central

    2014-01-01

    In this study, a ‘green chemistry’ approach was introduced to synthesize silk sericin (SS)-capped silver nanoparticles (AgNPs) under an alkaline condition (pH 11) using SS as a reducing and stabilizing agent instead of toxic chemicals. The SS-capped AgNPs were successfully synthesized at various concentrations of SS and AgNO3, but the yields were different. A higher yield of SS-capped AgNPs was obtained when the concentrations of SS and AgNO3 were increased. The SS-capped AgNPs showed a round shape and uniform size with diameter at around 48 to 117 nm. The Fourier transform infrared (FT-IR) spectroscopy result proved that the carboxylate groups obtained from alkaline degradation of SS would be a reducing agent for the generation of AgNPs while COO− and NH2 + groups stabilized the AgNPs and prevented their precipitation or aggregation. Furthermore, the SS-capped AgNPs showed potent anti-bacterial activity against various gram-positive bacteria (minimal inhibitory concentration (MIC) 0.008 mM) and gram-negative bacteria (MIC ranging from 0.001 to 0.004 mM). Therefore, the SS-capped AgNPs would be a safe candidate for anti-bacterial applications. PMID:24533676

  9. Glycosylated enfuvirtide: a long-lasting glycopeptide with potent anti-HIV activity.

    PubMed

    Cheng, Shuihong; Chang, Xuesong; Wang, Yan; Gao, George F; Shao, Yiming; Ma, Liying; Li, Xuebing

    2015-02-12

    Many peptide-based therapeutics have short circulatory half-lives. We report here that the pharmacokinetics of an anti-HIV peptide drug enfuvirtide (ENF) can be dramatically improved by a chemical glycosylation approach. A set of glycosylated ENFs with varying glycosylation sites and glycan structures were synthesized. Among these, a sialic acid-introduced peptide (SL-ENF) demonstrated a 15-fold extended half-life in rats relative to ENF (T1/2: 23.1 vs 1.5 h), and its antiviral potency was comparable to that of ENF (EC50: 2 vs 3 nM). SL-ENF bound to a functional fragment of the HIV fusogenic protein gp41 and formed complexes with high affinity and α-helicity, revealing the mechanism behind its potent antiviral activity. Because it is widely accepted in biology that glycosylation protects proteins from denaturation and proteases, our approach may be useful for the development of novel protein and peptide drugs with enhanced pharmaceutical properties.

  10. Novel arylalkylamine compounds exhibits potent selective antiparasitic activity against Leishmania major

    PubMed Central

    Iniguez, Eva A.; Perez, Andrea; Maldonado, Rosa A.; Skouta, Rachid

    2015-01-01

    Leishmania major (L. major) is a protozoan parasite causal agent of Leishmaniasis. It is estimated that 12 million people are currently infected and around 2 million infections occur each year. Current treatments suffer of high toxicity for the patient, low efficacy toward the parasite, high cost, and are losing effectiveness due to parasite resistance. Discovering novel small molecule with high specificity/selectivity and drug-like properties for anti-leishmanial activity remains a significant challenge. The purpose of this study is to communicate the design and synthesis strategies of novel chemical compounds based of the arylalkylamine scaffold with selective toxicity towards L. major and less toxicity to human cells in vitro. Here, we have developed a structure activity relationship (SAR) study of arylalkylamine AA1 in order to study their anti-parasitic effect in L. major. Overall, 27 arylalkylamine compounds derived from AA1 were synthesized and purified by silica gel column chromatography. The purity of each analog was confirmed by spectroscopic methods (1H, 13C NMR and LC/MS). Among these analogs, the compound AA9 showed the best toxic activity on L. major (LD50 = 3.34 μM), which represents a 9 fold higher lethality as compared with its parental AA1 (Fer-1) compound (LD50 = 28.75 μM). In addition, AA9 showed no significant toxicity at 80 μM on U20S Human Osteoblasts, Raw 264.7 Macrophages or intraperitoneal macrophages. In summary, our combined SAR study and biological evaluation data of AA1-AA27 compounds allow the identification of novel arylalkylamine compound AA9 that exhibits potent cytotoxicity against L. major promastigote with minimum toxic effect on human cells. PMID:26410073

  11. Chicken cathelicidins as potent intrinsically disordered biocides with antimicrobial activity against infectious pathogens.

    PubMed

    Yacoub, Haitham A; Elazzazy, Ahmed M; Mahmoud, Maged M; Baeshen, Mohamed Nabih; Al-Maghrabi, Omar A; Alkarim, Saleh; Ahmed, Ekram S; Almehdar, Hussein A; Uversky, Vladimir N

    2016-12-01

    This study was performed to identify the expression patterns of the cathelicidin genes in a local chicken breed and to evaluate the antimicrobial activities of the cathelicidin peptides against pathogenic bacteria. This analysis revealed that the coding regions of CATH-1, -2, and -3 genes contain 447 bp, 465 bp, and 456 bp, respectively, and encode proteins of 148, 154, 151 amino acids, respectively. The complete amino acid sequences of the cathelicidin peptides are similar to those found in Meleagris gallopavo, Phasianus colchicus, and Coturnix coturnix, and show high sequence identity to their Columba livia and Anas platyrhynchos counterparts. In contrast, these avian peptides shared a very low sequence identity with the mammalian cathelicidins. The analysis further revealed that the cathelicidin genes are expressed in various organ and tissues. We also show that the CATH peptides 1, 2, 3 and their amide-modified structures possess potent antimicrobial activities against both Gram-positive and Gram-negative pathogens, with these bacteria being affected to different extents. The antimicrobial activities of the peptides are slightly lower than those of their amide analogs. Computational analysis revealed that pre-pro-cathelicidins are hybrid proteins that contain ordered domains and functional intrinsically disordered regions. Furthermore, high structural and sequence variability of mature cathelicidins is a strong indication of their rather disordered nature. It is likely that intrinsic disorder is needed for the multifarious functionality of these antimicrobial peptides. Our analyses indicated that cathelicidin peptides require further study to better understand their full potentials in the treatment of diseases in both humans and animals. The data obtained for synthetic avian peptides will help elucidating of their potential applications in the pharmaceutical industry.

  12. Novel arylalkylamine compounds exhibits potent selective antiparasitic activity against Leishmania major.

    PubMed

    Iniguez, Eva A; Perez, Andrea; Maldonado, Rosa A; Skouta, Rachid

    2015-11-15

    Leishmania major (L. major) is a protozoan parasite causal agent of Leishmaniasis. It is estimated that 12 million people are currently infected and around 2 million infections occur each year. Current treatments suffer of high toxicity for the patient, low efficacy toward the parasite, high cost, and are losing effectiveness due to parasite resistance. Discovering novel small molecule with high specificity/selectivity and drug-like properties for anti-leishmanial activity remains a significant challenge. The purpose of this study is to communicate the design and synthesis strategies of novel chemical compounds based of the arylalkylamine scaffold with selective toxicity towards L. major and less toxicity to human cells in vitro. Here, we have developed a structure activity relationship (SAR) study of arylalkylamine AA1 in order to study their anti-parasitic effect in L. major. Overall, 27 arylalkylamine compounds derived from AA1 were synthesized and purified by silica gel column chromatography. The purity of each analog was confirmed by spectroscopic methods ((1)H, (13)C NMR and LC/MS). Among these analogs, the compound AA9 showed the best toxic activity on L. major (LD50=3.34 μM), which represents a 9 fold higher lethality as compared with its parental AA1 (Fer-1) compound (LD50=28.75 μM). In addition, AA9 showed no significant toxicity at 80 μM on U20S Human Osteoblasts, Raw 264.7 Macrophages or intraperitoneal macrophages. In summary, our combined SAR study and biological evaluation data of AA1-AA27 compounds allow the identification of novel arylalkylamine compound AA9 that exhibits potent cytotoxicity against L. major promastigote with minimum toxic effect on human cells. PMID:26410073

  13. Platelet-activating factor acetylhydrolase: selective inhibition by potent n-alkyl methylphosphonofluoridates.

    PubMed

    Quistad, Gary B; Fisher, Karl J; Owen, Sarah C; Klintenberg, Rebecka; Casida, John E

    2005-06-01

    Platelet-activating factor (PAF) is a potent endogenous phospholipid modulator of diverse biological activities, including inflammation and shock. PAF levels are primarily regulated by PAF acetylhydrolases (PAF-AHs). These enzymes are candidate secondary targets of organophosphorus (OP) pesticides and related toxicants. Previously known OP inhibitors of other serine hydrolases were tested with PAF-AH from mouse brain and testes of established functional importance compared with the structurally different human plasma enzyme. Several key OP pesticides and their oxon metabolites were very poor inhibitors of mouse brain and human plasma PAF-AH in vitro but moderately active for mouse brain and blood PAF-AH in vivo (e.g., tribufos defoliant and profenofos insecticide, presumably following oxidative bioactivation). OP compounds were then designed for maximum in vitro potency and selectivity for mouse brain PAF-AH vs. acetylcholinesterase (AChE). Lead compounds were found in a series of benzodioxaphosphorin 2-oxides. Ultrahigh potency and selectivity were achieved with n-alkyl methylphosphonofluoridates (long-chain sarin analogs): mouse brain and testes IC50 < or = 5 nM for C(8)-C(18) analogs and 0.1-0.6 nM for C(13) and C(14) compounds; human plasma IC50 < or = 2 nM for C(13)-C(18) analogs. AChE inhibitory potency decreased as chain length increased with maximum brain PAF-AH/AChE selectivity (>3000-fold) for C(13)-C(18) compounds. The toxicity of i.p.-administered PAF (LD50 ca. 0.5 mg/kg) was increased less than 2-fold by pretreatment with tribufos or the C(13)n-alkyl methylphosphonofluoridate. These studies with a mouse model indicate that PAF-AH is not a major secondary target of OP pesticide poisoning. The optimized PAF-AH inhibitors may facilitate investigations on other aspects of PAF metabolism and action.

  14. Platelet-activating factor acetylhydrolase: selective inhibition by potent n-alkyl methylphosphonofluoridates.

    PubMed

    Quistad, Gary B; Fisher, Karl J; Owen, Sarah C; Klintenberg, Rebecka; Casida, John E

    2005-06-01

    Platelet-activating factor (PAF) is a potent endogenous phospholipid modulator of diverse biological activities, including inflammation and shock. PAF levels are primarily regulated by PAF acetylhydrolases (PAF-AHs). These enzymes are candidate secondary targets of organophosphorus (OP) pesticides and related toxicants. Previously known OP inhibitors of other serine hydrolases were tested with PAF-AH from mouse brain and testes of established functional importance compared with the structurally different human plasma enzyme. Several key OP pesticides and their oxon metabolites were very poor inhibitors of mouse brain and human plasma PAF-AH in vitro but moderately active for mouse brain and blood PAF-AH in vivo (e.g., tribufos defoliant and profenofos insecticide, presumably following oxidative bioactivation). OP compounds were then designed for maximum in vitro potency and selectivity for mouse brain PAF-AH vs. acetylcholinesterase (AChE). Lead compounds were found in a series of benzodioxaphosphorin 2-oxides. Ultrahigh potency and selectivity were achieved with n-alkyl methylphosphonofluoridates (long-chain sarin analogs): mouse brain and testes IC50 < or = 5 nM for C(8)-C(18) analogs and 0.1-0.6 nM for C(13) and C(14) compounds; human plasma IC50 < or = 2 nM for C(13)-C(18) analogs. AChE inhibitory potency decreased as chain length increased with maximum brain PAF-AH/AChE selectivity (>3000-fold) for C(13)-C(18) compounds. The toxicity of i.p.-administered PAF (LD50 ca. 0.5 mg/kg) was increased less than 2-fold by pretreatment with tribufos or the C(13)n-alkyl methylphosphonofluoridate. These studies with a mouse model indicate that PAF-AH is not a major secondary target of OP pesticide poisoning. The optimized PAF-AH inhibitors may facilitate investigations on other aspects of PAF metabolism and action. PMID:15893542

  15. Structure-activity relationships for organometallic osmium arene phenylazopyridine complexes with potent anticancer activity.

    PubMed

    Fu, Ying; Habtemariam, Abraha; Basri, Aida M B H; Braddick, Darren; Clarkson, Guy J; Sadler, Peter J

    2011-10-28

    We report the synthesis and characterisation of 32 half sandwich phenylazopyridine Os(II) arene complexes [Os(η(6)-arene)(phenylazopyridine)X](+) in which X is chloride or iodide, the arene is p-cymene or biphenyl and the pyridine and phenyl rings contain a variety of substituents (F, Cl, Br, I, CF(3), OH or NO(2)). Ten X-ray crystal structures have been determined. Cytotoxicity towards A2780 human ovarian cancer cells ranges from high potency at nanomolar concentrations to inactivity. In general the introduction of an electron-withdrawing group (e.g. F, Cl, Br or I) at specific positions on the pyridine ring significantly increases cytotoxic activity and aqueous solubility. Changing the arene from p-cymene to biphenyl and the monodentate ligand X from chloride to iodide also increases the activity significantly. Activation by hydrolysis and DNA binding appears not to be the major mechanism of action since both the highly active complex [Os(η(6)-bip)(2-F-azpy)I]PF(6) (9) and the moderately active complex [Os(η(6)-bip)(3-Cl-azpy)I]PF(6) (23) are very stable and inert towards aquation. Studies of octanol-water partition coefficients (log P) and subcellular distributions of osmium in A2780 human ovarian cancer cells suggested that cell uptake and targeting to cellular organelles play important roles in determining activity. Although complex 9 induced the production of reactive oxygen species (ROS) in A2780 cells, the ROS level did not appear to play a role in the mechanism of anticancer activity. This class of organometallic osmium complexes has new and unusual features worthy of further exploration for the design of novel anticancer drugs.

  16. Delta- and gamma-tocotrienol isomers are potent in inhibiting inflammation and endothelial activation in stimulated human endothelial cells

    PubMed Central

    Muid, Suhaila; Froemming, Gabriele R. Anisah; Rahman, Thuhairah; Ali, A. Manaf; Nawawi, Hapizah M.

    2016-01-01

    Background Tocotrienols (TCTs) are more potent antioxidants than α-tocopherol (TOC). However, the effectiveness and mechanism of the action of TCT isomers as anti-atherosclerotic agents in stimulated human endothelial cells under inflammatory conditions are not well established. Aims 1) To compare the effects of different TCT isomers on inflammation, endothelial activation, and endothelial nitric oxide synthase (eNOS). 2) To identify the two most potent TCT isomers in stimulated human endothelial cells. 3) To investigate the effects of TCT isomers on NFκB activation, and protein and gene expression levels in stimulated human endothelial cells. Methods Human umbilical vein endothelial cells were incubated with various concentrations of TCT isomers or α-TOC (0.3–10 µM), together with lipopolysaccharides for 16 h. Supernatant cells were collected and measured for protein and gene expression of cytokines (interleukin-6, or IL-6; tumor necrosis factor-alpha, or TNF-α), adhesion molecules (intercellular cell adhesion molecule-1, or ICAM-1; vascular cell adhesion molecule-1, or VCAM-1; and e-selectin), eNOS, and NFκB. Results δ-TCT is the most potent TCT isomer in the inhibition of IL-6, ICAM-1, VCAM-1, and NFκB, and it is the second potent in inhibiting e-selectin and eNOS. γ-TCT isomer is the most potent isomer in inhibiting e-selectin and eNOS, and it is the second most potent in inhibiting is IL-6, VCAM-1, and NFκB. For ICAM-1 protein expression, the most potent is δ-TCT followed by α-TCT. α- and β-TCT inhibit IL-6 at the highest concentration (10 µM) but enhance IL-6 at lower concentrations. γ-TCT markedly increases eNOS expression by 8–11-fold at higher concentrations (5–10 µM) but exhibits neutral effects at lower concentrations. Conclusion δ- and γ-TCT are the two most potent TCT isomers in terms of the inhibition of inflammation and endothelial activation whilst enhancing eNOS, possibly mediated via the NFκB pathway. Hence, there is a

  17. Cissampelos pareira Linn: Natural Source of Potent Antiviral Activity against All Four Dengue Virus Serotypes

    PubMed Central

    Sood, Ruchi; Raut, Rajendra; Tyagi, Poornima; Pareek, Pawan Kumar; Barman, Tarani Kanta; Singhal, Smita; Shirumalla, Raj Kumar; Kanoje, Vijay; Subbarayan, Ramesh; Rajerethinam, Ravisankar; Sharma, Navin; Kanaujia, Anil; Shukla, Gyanesh; Gupta, Y. K.; Katiyar, Chandra K.; Bhatnagar, Pradip K.; Upadhyay, Dilip J.; Swaminathan, Sathyamangalam; Khanna, Navin

    2015-01-01

    Background Dengue, a mosquito-borne viral disease, poses a significant global public health risk. In tropical countries such as India where periodic dengue outbreaks can be correlated to the high prevalence of the mosquito vector, circulation of all four dengue viruses (DENVs) and the high population density, a drug for dengue is being increasingly recognized as an unmet public health need. Methodology/Principal findings Using the knowledge of traditional Indian medicine, Ayurveda, we developed a systematic bioassay-guided screening approach to explore the indigenous herbal bio-resource to identify plants with pan-DENV inhibitory activity. Our results show that the alcoholic extract of Cissampelos pariera Linn (Cipa extract) was a potent inhibitor of all four DENVs in cell-based assays, assessed in terms of viral NS1 antigen secretion using ELISA, as well as viral replication, based on plaque assays. Virus yield reduction assays showed that Cipa extract could decrease viral titers by an order of magnitude. The extract conferred statistically significant protection against DENV infection using the AG129 mouse model. A preliminary evaluation of the clinical relevance of Cipa extract showed that it had no adverse effects on platelet counts and RBC viability. In addition to inherent antipyretic activity in Wistar rats, it possessed the ability to down-regulate the production of TNF-α, a cytokine implicated in severe dengue disease. Importantly, it showed no evidence of toxicity in Wistar rats, when administered at doses as high as 2g/Kg body weight for up to 1 week. Conclusions/Significance Our findings above, taken in the context of the human safety of Cipa, based on its use in Indian traditional medicine, warrant further work to explore Cipa as a source for the development of an inexpensive herbal formulation for dengue therapy. This may be of practical relevance to a dengue-endemic resource-poor country such as India. PMID:26709822

  18. Identification of a potent synthetic FXR agonist with an unexpected mode of binding and activation

    SciTech Connect

    Soisson, Stephen M.; Parthasarathy, Gopalakrishnan; Adams, Alan D.; Sahoo, Soumya; Sitlani, Ayesha; Sparrow, Carl; Cui, Jisong; Becker, Joseph W.

    2008-07-08

    The farnesoid X receptor (FXR), a member of the nuclear hormone receptor family, plays important roles in the regulation of bile acid and cholesterol homeostasis, glucose metabolism, and insulin sensitivity. There is intense interest in understanding the mechanisms of FXR regulation and in developing pharmaceutically suitable synthetic FXR ligands that might be used to treat metabolic syndrome. We report here the identification of a potent FXR agonist (MFA-1) and the elucidation of the structure of this ligand in ternary complex with the human receptor and a coactivator peptide fragment using x-ray crystallography at 1.9-{angstrom} resolution. The steroid ring system of MFA-1 binds with its D ring-facing helix 12 (AF-2) in a manner reminiscent of hormone binding to classical steroid hormone receptors and the reverse of the pose adopted by naturally occurring bile acids when bound to FXR. This binding mode appears to be driven by the presence of a carboxylate on MFA-1 that is situated to make a salt-bridge interaction with an arginine residue in the FXR-binding pocket that is normally used to neutralize bound bile acids. Receptor activation by MFA-1 differs from that by bile acids in that it relies on direct interactions between the ligand and residues in helices 11 and 12 and only indirectly involves a protonated histidine that is part of the activation trigger. The structure of the FXR:MFA-1 complex differs significantly from that of the complex with a structurally distinct agonist, fexaramine, highlighting the inherent plasticity of the receptor.

  19. Abietane-Type Diterpenoid Amides with Highly Potent and Selective Activity against Leishmania donovani and Trypanosoma cruzi.

    PubMed

    Pirttimaa, Minni; Nasereddin, Abedelmajeed; Kopelyanskiy, Dmitry; Kaiser, Marcel; Yli-Kauhaluoma, Jari; Oksman-Caldentey, Kirsi-Marja; Brun, Reto; Jaffe, Charles L; Moreira, Vânia M; Alakurtti, Sami

    2016-02-26

    Dehydroabietylamine (1) was used as a starting material to synthesize a small library of dehydroabietyl amides by simple and facile methods, and their activities against two disease-causing trypanosomatids, namely, Leishmania donovani and Trypanosoma cruzi, were assayed. The most potent compound, 10, an amide of dehydroabietylamine and acrylic acid, was found to be highly potent against these parasites, displaying an IC50 value of 0.37 μM against L. donovani axenic amastigotes and an outstanding selectivity index of 63. Moreover, compound 10 fully inhibited the growth of intracellular amastigotes in Leishmania donovani-infected human macrophages with a low IC50 value of 0.06 μM. This compound was also highly effective against T. cruzi amastigotes residing in L6 cells with an IC50 value of 0.6 μM and high selectivity index of 58, being 3.5 times more potent than the reference compound benznidazole. The potent activity of this compound and its relatively low cytotoxicity make it attractive for further development in pursuit of better drugs for patients suffering from leishmaniasis and Chagas disease. PMID:26849852

  20. Activation of non-sensitizing or low-sensitizing fragrance substances into potent sensitizers - prehaptens and prohaptens.

    PubMed

    Karlberg, Ann-Therese; Börje, Anna; Duus Johansen, Jeanne; Lidén, Carola; Rastogi, Suresh; Roberts, David; Uter, Wolfgang; White, Ian R

    2013-12-01

    Experimental and clinical studies have shown that fragrance substances can act as prehaptens or prohaptens. They form allergens that are more potent than the parent substance by activation outside or in the skin via abiotic (chemical and physical factors) and/or biotic activation, thus, increasing the risk of sensitization. In the present review a series of fragrance substances with well documented abiotic and/or biotic activation are given as indicative and illustrative examples of the general problem. Commonly used fragrance substances, also found in essential oils, autoxidize on contact with air, forming potent sensitizers that can be an important source for contact allergy to fragrances and fragranced products. Some of them can act as prohaptens and be activated in the skin as well. The experimental findings are confirmed in large clinical studies. When substances with structural alerts for acting as prohaptens and/or prehaptens are identified, the possibility of generating new potent allergens should be considered. Predictive testing should include activation steps. Further experimental and clinical research regarding activation of fragrance substances is needed to increase consumer safety.

  1. Structure-activity relationship of Garcinia xanthones analogues: Potent Hsp90 inhibitors with cytotoxicity and antiangiogenesis activity.

    PubMed

    Xu, Xiaoli; Wu, Yue; Hu, Mingyang; Li, Xiang; Gu, Congying; You, Qidong; Zhang, Xiaojin

    2016-10-01

    Hsp90 has long been recognized as an attractive and crucial molecular target for cancer therapy. Gambogic acid (GA), the main active compound of Gamboge hanburyi, has been reported as a natural inhibitor of Hsp90. Here, we present the structure-activity relationship of Garcinia xanthones analogues as Hsp90 inhibitors and identify that compound 25, with a simplified skeleton, had an improved inhibitory effect toward Hsp90. Compound 25 inhibited the ATPase activity of Hsp90 with an IC50 value of 3.68±0.18μM. It also exhibited potent antiproliferative activities in some solid tumor cells. In SK-BR-3 cells with high Hsp90 expression, compound 25 induced the degradation of Hsp90 client proteins including Akt and Erk1/2 without causing the heat shock response. Additionally, compound 25 inhibited angiogenesis in HUVEC cells through Hsp90 regulation of the HIF-1α pathway. These results demonstrate that compound 25 as an Hsp90 inhibitor with a new structure could be further studied for the development of tumor therapy. PMID:27527413

  2. Synthesis and structure-activity relationship of pyripyropene A derivatives as potent and selective acyl-CoA:cholesterol acyltransferase 2 (ACAT2) inhibitors: part 1.

    PubMed

    Ohtawa, Masaki; Yamazaki, Hiroyuki; Ohte, Satoshi; Matsuda, Daisuke; Ohshiro, Taichi; Rudel, Lawrence L; Omura, Satoshi; Tomoda, Hiroshi; Nagamitsu, Tohru

    2013-03-01

    In an effort to develop potent and selective inhibitors toward ACAT2, structure-activity relationship studies were carried out using derivatives based on pyripyropene A (PPPA, 1). We have successfully developed novel PPPA derivatives with a 7-O-substituted benzoyl substituent that significantly exhibit more potent ACAT2 inhibitory activity and higher ACAT2 isozyme selectivity than 1. PMID:23369538

  3. Urolithins, Intestinal Microbial Metabolites of Pomegranate Ellagitannins, Exhibit Potent Antioxidant Activity in Cell-Based Assay

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many health benefits of pomegranate products have been attributed to the potent antioxidant action of their tannin components, mainly punicalagins and ellagic acid. While moving through the intestines, ellagitannins are metabolized by gut bacteria into urolithins that readily enter systemic circulat...

  4. Potent inhibitory effects of N-aryl S-alkylthiocarbamate derivatives on the dopa oxidase activity of mushroom tyrosinase.

    PubMed

    Lee, Kun Ho; Koketsu, Mamoru; Choi, Sang Yoon; Lee, Kang Jin; Lee, Pyeongjae; Ishihara, Hideharu; Kim, Sun Yeou

    2005-07-01

    This study reports the potent inhibitory effect of N-aryl S-alkylthiocarbamate derivatives on mushroom tyrosinase (MT) activity. N-Aryl S-alkylthiocarbamate derivatives were found to exhibit a potent inhibitory effect on the dopa (3,4-dihydroxyphenylalanine) oxidase activity of mushroom tyrosinase. Most of the N-aryl S-alkylthiocarbamate derivatives (compounds from A to J) exhibited higher inhibitory effects than kojic acid (IC50=318 microM), a well known tyrosinase inhibitor. Tyrosinase was the most inhibited by S-phenetyl N-phenylthiocarbamate (compound E, IC50=7.25 microM), and this inhibition was 44 times stronger than that of kojic acid. Compound E exhibited 95.0% of inhibition at 100 microM. A kinetic study of MT inhibition by compound E using the Lineweaver-Burk plots analysis was performed. And the kinetics profiles observed suggest that compound E competitively inhibits MT.

  5. Acetoxybenzhydrols as highly active and stable analogues of 1'S-1'-acetoxychavicol, a potent antiallergic principal from Alpinia galanga.

    PubMed

    Yasuhara, Tomohisa; Manse, Yoshiaki; Morimoto, Takayuki; Qilong, Wang; Matsuda, Hisashi; Yoshikawa, Masayuki; Muraoka, Osamu

    2009-06-01

    Through SAR studies on 1'S-1'-acetoxychavicol acetate (1) against Type I antiallergic activity by indexing release of beta-hexosaminidase, a marker of antigen-IgE-mediated degranulation in RBL-2H3 cells, more stable and potent analogue, 4-(methoxycarbonyloxyphenylmethyl)phenyl acetate (16), has been developed. The compound 16 also strongly inhibited the antigen-IgE-mediated TNF-alpha and IL-4 production.

  6. Discovery of a series of cyclohexylethylamine-containing protein farnesyltransferase inhibitors exhibiting potent cellular activity.

    PubMed

    Henry, K J; Wasicak, J; Tasker, A S; Cohen, J; Ewing, P; Mitten, M; Larsen, J J; Kalvin, D M; Swenson, R; Ng, S C; Saeed, B; Cherian, S; Sham, H; Rosenberg, S H

    1999-11-18

    Synthesis of a library of secondary benzylic amines based on the Sebti-Hamilton type peptidomimetic farnesyltransferase (FTase) inhibitor FTI-276 (1) led to the identification of 6 as a potent enzyme inhibitor (IC(50) of 8 nM) which lacked the problematic thiol residue which had been a common theme in many of the more important FTase inhibitors reported to date. It has previously been disclosed that addition of o-tolyl substitution to FTase inhibitors of the general description 2 had a salutary effect on both FTase inhibition and inhibition of Ras prenylation in whole cells. Combination of these two observations led us to synthesize 7, a potent FTase inhibitor which displayed an IC(50) of 0.16 nM for in vitro inhibition of FTase and an EC(50) of 190 nM for inhibition of whole cell Ras prenylation. Modification of 7 by classical medicinal chemistry led to the discovery of a series of potent FTase inhibitors, culminating in the identification of 25 which exhibited an IC(50) of 0.20 nM and an EC(50) of 4.4 nM. In vivo tests in a nude mouse xenograft model of human pancreatic cancer (MiaPaCa cells) showed that oral dosing of 25 gave rise to impressive attenuation of the growth of this aggressive tumor cell line.

  7. Isoliquiritigenin is a potent inhibitor of NLRP3 inflammasome activation and diet-induced adipose tissue inflammation.

    PubMed

    Honda, Hiroe; Nagai, Yoshinori; Matsunaga, Takayuki; Okamoto, Naoki; Watanabe, Yasuharu; Tsuneyama, Koichi; Hayashi, Hiroaki; Fujii, Isao; Ikutani, Masashi; Hirai, Yoshikatsu; Muraguchi, Atsushi; Takatsu, Kiyoshi

    2014-12-01

    Inflammasome activation initiates the development of many inflammatory diseases, including obesity and type 2 diabetes. Therefore, agents that target discrete activation steps could represent very important drugs. We reported previously that ILG, a chalcone from Glycyrrhiza uralensis, inhibits LPS-induced NF-κB activation. Here, we show that ILG potently inhibits the activation of NLRP3 inflammasome, and the effect is independent of its inhibitory potency on TLR4. The inhibitory effect of ILG was stronger than that of parthenolide, a known inhibitor of the NLRP3 inflammasome. GL, a triterpenoid from G. uralensis, had similar inhibitory effects on NLRP3 activity, but high concentrations of GL were required. In contrast, activation of the AIM2 inflammasome was inhibited by GL but not by ILG. Moreover, GL inhibited NLRP3- and AIM2-activated ASC oligomerization, whereas ILG inhibited NLRP3-activated ASC oligomerization. Low concentrations of ILG were highly effective in IAPP-induced IL-1β production compared with the sulfonylurea drug glyburide. In vivo analyses revealed that ILG potently attenuated HFD-induced obesity, hypercholesterolemia, and insulin resistance. Furthermore, ILG treatment improved HFD-induced macrovesicular steatosis in the liver. Finally, ILG markedly inhibited diet-induced adipose tissue inflammation and IL-1β and caspase-1 production in white adipose tissue in ex vivo culture. These results suggest that ILG is a potential drug target for treatment of NLRP3 inflammasome-associated inflammatory diseases. PMID:25210146

  8. Anthelmintic properties of traditional African and Caribbean medicinal plants: identification of extracts with potent activity against Ascaris suum in vitro

    PubMed Central

    Williams, Andrew R.; Soelberg, Jens; Jäger, Anna K.

    2016-01-01

    Ascariasis affects more than 1 billion people worldwide, mainly in developing countries, causing substantial morbidity. Current treatments for Ascaris infection are based on mass drug administration (MDA) with synthetic anthelmintic drugs such as albendazole, however continual re-infection and the threat of drug resistance mean that complementary treatment options would be highly valuable. Here, we screened ethanolic extracts from 29 medicinal plants used in Africa (Ghana) and the Caribbean (US Virgin Islands) for in vitro anthelmintic properties against Ascaris suum, a swine parasite that is very closely related to the human A. lumbricoides. A wide variety of activities were seen in the extracts, from negligible to potent. Extracts from Clausena anisata, Zanthoxylum zanthoxyloides and Punica granatum were identified as the most potent with EC50 values of 74, 97 and 164 μg/mL, respectively. Our results encourage further investigation of their use as complementary treatment options for ascariasis, alongside MDA. PMID:27301442

  9. New Pyrrole Derivatives with Potent Tubulin Polymerization Inhibiting Activity As Anticancer Agents Including Hedgehog-Dependent Cancer

    PubMed Central

    La Regina, Giuseppe; Bai, Ruoli; Coluccia, Antonio; Famiglini, Valeria; Pelliccia, Sveva; Passacantilli, Sara; Mazzoccoli, Carmela; Ruggieri, Vitalba; Sisinni, Lorenza; Bolognesi, Alessio; Rensen, Whilelmina Maria; Miele, Andrea; Nalli, Marianna; Alfonsi, Romina; Di Marcotullio, Lucia; Gulino, Alberto; Brancale, Andrea; Novellino, Ettore; Dondio, Giulio; Vultaggio, Stefania; Varasi, Mario; Mercurio, Ciro; Hamel, Ernest; Lavia, Patrizia; Silvestri, Romano

    2014-01-01

    We synthesized 3-aroyl-1-arylpyrrole (ARAP) derivatives as potential anticancer agents having different substituents at the pendant 1-phenyl ring. Both the 1-phenyl ring and 3-(3,4,5-trimethoxyphenyl)carbonyl moieties were mandatory to achieve potent inhibition of tubulin polymerization, binding of colchicine to tubulin, and cancer cell growth. ARAP 22 showed strong inhibition of the P-glycoprotein-overexpressing NCI-ADR-RES and Messa/Dx5MDR cell lines. Compounds 22 and 27 suppressed in vitro the Hedgehog signaling pathway, strongly reducing luciferase activity in SAG treated NIH3T3 Shh-Light II cells, and inhibited the growth of medulloblastoma D283 cells at nanomolar concentrations. ARAPs 22 and 27 represent a new potent class of tubulin polymerization and cancer cell growth inhibitors with the potential to inhibit the Hedgehog signaling pathway. PMID:25025991

  10. Anthelmintic properties of traditional African and Caribbean medicinal plants: identification of extracts with potent activity against Ascaris suum in vitro.

    PubMed

    Williams, Andrew R; Soelberg, Jens; Jäger, Anna K

    2016-01-01

    Ascariasis affects more than 1 billion people worldwide, mainly in developing countries, causing substantial morbidity. Current treatments for Ascaris infection are based on mass drug administration (MDA) with synthetic anthelmintic drugs such as albendazole, however continual re-infection and the threat of drug resistance mean that complementary treatment options would be highly valuable. Here, we screened ethanolic extracts from 29 medicinal plants used in Africa (Ghana) and the Caribbean (US Virgin Islands) for in vitro anthelmintic properties against Ascaris suum, a swine parasite that is very closely related to the human A. lumbricoides. A wide variety of activities were seen in the extracts, from negligible to potent. Extracts from Clausena anisata, Zanthoxylum zanthoxyloides and Punica granatum were identified as the most potent with EC50 values of 74, 97 and 164 μg/mL, respectively. Our results encourage further investigation of their use as complementary treatment options for ascariasis, alongside MDA. PMID:27301442

  11. Anthelmintic properties of traditional African and Caribbean medicinal plants: identification of extracts with potent activity against Ascaris suum in vitro.

    PubMed

    Williams, Andrew R; Soelberg, Jens; Jäger, Anna K

    2016-01-01

    Ascariasis affects more than 1 billion people worldwide, mainly in developing countries, causing substantial morbidity. Current treatments for Ascaris infection are based on mass drug administration (MDA) with synthetic anthelmintic drugs such as albendazole, however continual re-infection and the threat of drug resistance mean that complementary treatment options would be highly valuable. Here, we screened ethanolic extracts from 29 medicinal plants used in Africa (Ghana) and the Caribbean (US Virgin Islands) for in vitro anthelmintic properties against Ascaris suum, a swine parasite that is very closely related to the human A. lumbricoides. A wide variety of activities were seen in the extracts, from negligible to potent. Extracts from Clausena anisata, Zanthoxylum zanthoxyloides and Punica granatum were identified as the most potent with EC50 values of 74, 97 and 164 μg/mL, respectively. Our results encourage further investigation of their use as complementary treatment options for ascariasis, alongside MDA.

  12. Structure-Activity Relationship of Amino Acid Tunable Lipidated Norspermidine Conjugates: Disrupting Biofilms with Potent Activity against Bacterial Persisters.

    PubMed

    Konai, Mohini M; Adhikary, Utsarga; Samaddar, Sandip; Ghosh, Chandradhish; Haldar, Jayanta

    2015-12-16

    The emergence of bacterial resistance and biofilm associated infections has created a challenging situation in global health. In this present state of affairs where conventional antibiotics are falling short of being able to provide a solution to these problems, development of novel antibacterial compounds possessing the twin prowess of antibacterial and antibiofilm efficacy is imperative. Herein, we report a library of amino acid tunable lipidated norspermidine conjugates that were prepared by conjugating both amino acids and fatty acids with the amine functionalities of norspermidine through amide bond formation. These lipidated conjugates displayed potent antibacterial activity against various planktonic Gram-positive and Gram-negative bacteria including drug-resistant superbugs such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecium, and β-lactam-resistant Klebsiella pneumoniae. This class of nontoxic and fast-acting antibacterial molecules (capable of killing bacteria within 15 min) did not allow bacteria to develop resistance against them after several passages. Most importantly, an optimized compound in the series was also capable of killing metabolically inactive persisters and stationary phase bacteria. Additionally, this compound was capable of disrupting the preformed biofilms of S. aureus and E. coli. Therefore, this class of antibacterial conjugates have potential in tackling the challenging situation posed by both bacterial resistance as well as drug tolerance due to biofilm formation. PMID:26452096

  13. Water fraction of edible medicinal fern Stenochlaena palustris is a potent α-glucosidase inhibitor with concurrent antioxidant activity.

    PubMed

    Chai, Tsun-Thai; Kwek, Meng-Tee; Ong, Hean-Chooi; Wong, Fai-Chu

    2015-11-01

    This study aimed to isolate a potent antiglucosidase and antioxidant fraction from Stenochlaena palustris. Extraction was performed with hexane, chloroform, ethyl acetate, methanol, and water. Antiglucosidase, 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging and ferric reducing antioxidant power (FRAP) assays found methanol extract (ME) to be the most active. Water fraction (WF) of ME was a stronger α-glucosidase inhibitor (EC50 2.9 μg/mL) than quercetin, with weak antiamylase activity. WF was a competitive α-glucosidase inhibitor. DPPH scavenging activity of WF (EC50 7.7 μg/mL) was weaker than quercetin. WF (EC50 364 μg/mL) was a stronger hydrogen peroxide scavenger than gallic acid (EC50 838 μg/mL) and was equally strong as quercetin in scavenging superoxide. WF possessed moderate copper chelating activity. WF was enriched in total phenolics (TP) and hydroxycinnamic acids (THC). TP correlated with antioxidant activity (R(2) > 0.76). Only THC correlated with antiglucosidase activity (R(2) = 0.86). Overall, WF demonstrated concurrent, potent antiglucosidase and antioxidant activities.

  14. Water fraction of edible medicinal fern Stenochlaena palustris is a potent α-glucosidase inhibitor with concurrent antioxidant activity.

    PubMed

    Chai, Tsun-Thai; Kwek, Meng-Tee; Ong, Hean-Chooi; Wong, Fai-Chu

    2015-11-01

    This study aimed to isolate a potent antiglucosidase and antioxidant fraction from Stenochlaena palustris. Extraction was performed with hexane, chloroform, ethyl acetate, methanol, and water. Antiglucosidase, 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging and ferric reducing antioxidant power (FRAP) assays found methanol extract (ME) to be the most active. Water fraction (WF) of ME was a stronger α-glucosidase inhibitor (EC50 2.9 μg/mL) than quercetin, with weak antiamylase activity. WF was a competitive α-glucosidase inhibitor. DPPH scavenging activity of WF (EC50 7.7 μg/mL) was weaker than quercetin. WF (EC50 364 μg/mL) was a stronger hydrogen peroxide scavenger than gallic acid (EC50 838 μg/mL) and was equally strong as quercetin in scavenging superoxide. WF possessed moderate copper chelating activity. WF was enriched in total phenolics (TP) and hydroxycinnamic acids (THC). TP correlated with antioxidant activity (R(2) > 0.76). Only THC correlated with antiglucosidase activity (R(2) = 0.86). Overall, WF demonstrated concurrent, potent antiglucosidase and antioxidant activities. PMID:25976787

  15. Identification of a novel multiple kinase inhibitor with potent antiviral activity against influenza virus by reducing viral polymerase activity

    SciTech Connect

    Sasaki, Yutaka; Kakisaka, Michinori; Chutiwitoonchai, Nopporn; Tajima, Shigeru; Hikono, Hirokazu; Saito, Takehiko; Aida, Yoko

    2014-07-18

    Highlights: • Screening of 50,000 compounds and subsequent lead optimization identified WV970. • WV970 has antiviral effects against influenza A, B and highly pathogenic viral strains. • WV970 inhibits viral genome replication and transcription. • A target database search suggests that WV970 may bind to a number of kinases. • KINOMEscan screening revealed that WV970 has inhibitory effects on 15 kinases. - Abstract: Neuraminidase inhibitors are the only currently available influenza treatment, although resistant viruses to these drugs have already been reported. Thus, new antiviral drugs with novel mechanisms of action are urgently required. In this study, we identified a novel antiviral compound, WV970, through cell-based screening of a 50,000 compound library and subsequent lead optimization. This compound exhibited potent antiviral activity with nanomolar IC{sub 50} values against both influenza A and B viruses but not non-influenza RNA viruses. Time-of-addition and indirect immunofluorescence assays indicated that WV970 acted at an early stage of the influenza life cycle, but likely after nuclear entry of viral ribonucleoprotein (vRNP). Further analyses of viral RNA expression and viral polymerase activity indicated that WV970 inhibited vRNP-mediated viral genome replication and transcription. Finally, structure-based virtual screening and comprehensive human kinome screening were used to demonstrate that WV970 acts as a multiple kinase inhibitor, many of which are associated with influenza virus replication. Collectively, these results strongly suggest that WV970 is a promising anti-influenza drug candidate and that several kinases associated with viral replication are promising drug targets.

  16. Identification of a Potent Inhibitor of CREB-Mediated Gene Transcription with Efficacious in Vivo Anticancer Activity

    PubMed Central

    2015-01-01

    Recent studies have shown that nuclear transcription factor cyclic adenosine monophosphate response element binding protein (CREB) is overexpressed in many different types of cancers. Therefore, CREB has been pursued as a novel cancer therapeutic target. Naphthol AS-E and its closely related derivatives have been shown to inhibit CREB-mediated gene transcription and cancer cell growth. Previously, we identified naphthamide 3a as a different chemotype to inhibit CREB’s transcription activity. In a continuing effort to discover more potent CREB inhibitors, a series of structural congeners of 3a was designed and synthesized. Biological evaluations of these compounds uncovered compound 3i (666-15) as a potent and selective inhibitor of CREB-mediated gene transcription (IC50 = 0.081 ± 0.04 μM). 666-15 also potently inhibited cancer cell growth without harming normal cells. In an in vivo MDA-MB-468 xenograft model, 666-15 completely suppressed the tumor growth without overt toxicity. These results further support the potential of CREB as a valuable cancer drug target. PMID:26023867

  17. Potent bivalent Smac mimetics: effect of the linker on binding to inhibitor of apoptosis proteins (IAPs) and anticancer activity.

    PubMed

    Sun, Haiying; Liu, Liu; Lu, Jianfeng; Bai, Longchuan; Li, Xiaoqin; Nikolovska-Coleska, Zaneta; McEachern, Donna; Yang, Chao-Yie; Qiu, Su; Yi, Han; Sun, Duxin; Wang, Shaomeng

    2011-05-12

    We have synthesized and evaluated a series of nonpeptidic, bivalent Smac mimetics as antagonists of the inhibitor of apoptosis proteins and new anticancer agents. All these bivalent Smac mimetics bind to full-length XIAP with low nanomolar affinities and function as ultrapotent antagonists of XIAP. While these Smac mimetics bind to cIAP1/2 with similar low nanomolar affinities, their potencies to induce degradation of cIAP1/2 proteins in cells differ by more than 100-fold. The most potent bivalent Smac mimetics inhibit cell growth with IC(50) from 1 to 3 nM in the MDA-MB-231 breast cancer cell line and are 100 times more potent than the least potent compounds. Determination of intracellular concentrations for several representative compounds showed that the linkers in these bivalent Smac mimetics significantly affect their intracellular concentrations and hence the overall cellular activity. Compound 27 completely inhibits tumor growth in the MDA-MB-231 xenografts while causing no signs of toxicity in the animals.

  18. Cathelicidin Antimicrobial Peptides with Reduced Activation of Toll-Like Receptor Signaling Have Potent Bactericidal Activity against Colistin-Resistant Bacteria

    PubMed Central

    Lin, Xiaoyan; Yi, Guanghui; Zhang, Yunliang; Rowe-Magnus, Dean A.; Bush, Karen

    2016-01-01

    ABSTRACT The world is at the precipice of a postantibiotic era in which medical procedures and minor injuries can result in bacterial infections that are no longer effectively treated by antibiotics. Cathelicidins are peptides produced by animals to combat bacterial infections and to regulate innate immune responses. However, cathelicidins are potent activators of the inflammatory response. Cathelicidins with reduced proinflammatory activity and potent bactericidal activity in the low micromolar range against Gram-negative bacteria have been identified. Motifs in cathelicidins that impact bactericidal activity and cytotoxicity to human cells have been elucidated and used to generate peptides that have reduced activation of proinflammatory cytokine production and reduced cytotoxicity to human cells. The resultant peptides have bactericidal activities comparable to that of colistin and can kill colistin-resistant bacteria. PMID:27651360

  19. Structure–Activity Relationship Study Reveals ML240 and ML241 as Potent and Selective Inhibitors of p97 ATPase

    PubMed Central

    Chou, Tsui-Fen; Li, Kelin; Frankowski, Kevin J; Schoenen, Frank J; Deshaies, Raymond J

    2013-01-01

    To discover more potent p97 inhibitors, we carried out a structure–activity relationship study of the quinazoline scaffold previously identified from our HTS campaigns. Two improved inhibitors, ML240 and ML241, inhibit p97 ATPase with IC50 values of 100 nm. Both compounds inhibited degradation of a p97-dependent but not a p97-independent proteasome substrate in a dual-reporter cell line. They also impaired the endoplasmic-reticulum-associated degradation (ERAD) pathway. Unexpectedly, ML240 potently stimulated accumulation of LC3-II within minutes, inhibited cancer cell growth, and rapidly mobilized the executioner caspases 3 and 7, whereas ML241 did not. The behavior of ML240 suggests that disruption of the protein homeostasis function of p97 leads to more rapid activation of apoptosis than is observed with a proteasome inhibitor. Further characterization revealed that ML240 has broad antiproliferative activity toward the NCI-60 panel of cancer cell lines, but slightly lower activity toward normal cells. ML240 also synergizes with the proteasome inhibitor MG132 to kill multiple colon cancer cell lines. Meanwhile, both probes have low off-target activity toward a panel of protein kinases and central nervous system targets. Our results nominate ML240 as a promising starting point for the development of a novel agent for the chemotherapy of cancer, and provide a rationale for developing pathway-specific p97 inhibitors. PMID:23316025

  20. Taccalonolide binding to tubulin imparts microtubule stability and potent in vivo activity

    PubMed Central

    Risinger, AL; Li, J; Bennett, MJ; Rohena, CC; Peng, J; Schriemer, DC; Mooberry, SL

    2013-01-01

    The taccalonolides are highly acetylated steroids that stabilize cellular microtubules and overcome multiple mechanisms of taxane resistance. Recently, two potent taccalonolides, AF and AJ, were identified that bind tubulin directly and enhance microtubule polymerization. Extensive studies were conducted to characterize these new taccalonolides. AF and AJ caused aberrant mitotic spindles and bundling of interphase microtubules that differed from the effects of either paclitaxel or laulimalide. AJ also distinctly affected microtubule polymerization in that it enhanced the rate and extent of polymerization in the absence of any noticeable effect on microtubule nucleation. Additionally, the resulting microtubules were found to be profoundly cold stable. These data, along with studies showing synergistic antiproliferative effects between AJ and either paclitaxel or laulimalide, suggest a distinct binding site. Direct binding studies demonstrated that AJ could not be displaced from microtubules by paclitaxel, laulimalide or denaturing conditions, suggesting irreversible binding of AJ to microtubules. Mass spectrometry confirmed a covalent interaction of AJ with a peptide of β-tubulin containing the cyclostreptin binding sites. Importantly, AJ imparts strong inter-protofilament stability in a manner different from other microtubule stabilizers that covalently bind tubulin, consistent with the distinct effects of the taccalonolides as compared to other stabilizers. AF was found to be a potent and effective antitumor agent that caused tumor regression in the MDA-MB-231 breast cancer xenograft model. The antitumor efficacy of some taccalonolides, which stabilize microtubules in a manner different from other microtubule stabilizers, provides the impetus to explore the therapeutic potential of this site. PMID:24048820

  1. Resveratrol potently reduces prostaglandin E2 production and free radical formation in lipopolysaccharide-activated primary rat microglia

    PubMed Central

    Candelario-Jalil, Eduardo; de Oliveira, Antonio C Pinheiro; Gräf, Sybille; Bhatia, Harsharan S; Hüll, Michael; Muñoz, Eduardo; Fiebich, Bernd L

    2007-01-01

    Background Neuroinflammatory responses are triggered by diverse ethiologies and can provide either beneficial or harmful results. Microglial cells are the major cell type involved in neuroinflammation, releasing several mediators, which contribute to the neuronal demise in several diseases including cerebral ischemia and neurodegenerative disorders. Attenuation of microglial activation has been shown to confer protection against different types of brain injury. Recent evidence suggests that resveratrol has anti-inflammatory and potent antioxidant properties. It has been also shown that resveratrol is a potent inhibitor of cyclooxygenase (COX)-1 activity. Previous findings have demonstrated that this compound is able to reduce neuronal injury in different models, both in vitro and in vivo. The aim of this study was to examine whether resveratrol is able to reduce prostaglandin E2 (PGE2) and 8-iso-prostaglandin F2α (8-iso-PGF2α) production by lipopolysaccharide (LPS)-activated primary rat microglia. Methods Primary microglial cell cultures were prepared from cerebral cortices of neonatal rats. Microglial cells were stimulated with 10 ng/ml of LPS in the presence or absence of different concentrations of resveratrol (1–50 μM). After 24 h incubation, culture media were collected to measure the production of PGE2 and 8-iso-PGF2α using enzyme immunoassays. Protein levels of COX-1, COX-2 and microsomal prostaglandin E synthase-1 (mPGES-1) were studied by Western blotting after 24 h of incubation with LPS. Expression of mPGES-1 at the mRNA level was investigated using reverse transcription-polymerase chain reaction (RT-PCR) analysis. Results Our results indicate that resveratrol potently reduced LPS-induced PGE2 synthesis and the formation of 8-iso-PGF2α, a measure of free radical production. Interestingly, resveratrol dose-dependently reduced the expression (mRNA and protein) of mPGES-1, which is a key enzyme responsible for the synthesis of PGE2 by activated

  2. Fowlicidin-3 is an alpha-helical cationic host defense peptide with potent antibacterial and lipopolysaccharide-neutralizing activities.

    PubMed

    Bommineni, Yugendar R; Dai, Huaien; Gong, Yu-Xi; Soulages, Jose L; Fernando, Samodha C; Desilva, Udaya; Prakash, Om; Zhang, Guolong

    2007-01-01

    Cathelicidins are an important family of cationic host defense peptides in vertebrates with both antimicrobial and immunomodulatory activities. Fowlicidin-1 and fowlicidin-2 are two newly identified chicken cathelicidins with potent antibacterial activities. Here we report structural and functional characterization of the putatively mature form of the third chicken cathelicidin, fowlicidin-3, for exploration of its therapeutic potential. NMR spectroscopy revealed that fowlicidin-3 comprises 27 amino-acid residues and adopts a predominantly alpha-helical structure extending from residue 9 to 25 with a slight kink induced by a glycine at position 17. It is highly potent against a broad range of Gram-negative and Gram-positive bacteria in vitro, including antibiotic-resistant strains, with minimum inhibitory concentrations in the range 1-2 microM. It kills bacteria quickly, permeabilizing cytoplasmic membranes immediately on coming into contact with them. Unlike many other host defense peptides with antimicrobial activities that are diminished by serum or salt, fowlicidin-3 retains bacteria-killing activities in the presence of 50% serum or physiological concentrations of salt. Furthermore, it is capable of suppressing lipopolysaccharide-induced expression of proinflammatory genes in mouse macrophage RAW264.7 cells, with nearly complete blockage at 10 microM. Fowlicidin-3 appears to be an excellent candidate for future development as a novel antimicrobial and antisepsis agent, particularly against antibiotic-resistant pathogens.

  3. A potential endogenous ligand for the aryl hydrocarbon receptor has potent agonist activity in vitro and in vivo.

    PubMed

    Henry, E C; Bemis, J C; Henry, O; Kende, A S; Gasiewicz, T A

    2006-06-01

    The aryl hydrocarbon receptor (AhR) is best known as a mediator of toxicity of a diverse family of xenobiotic chemicals such as dioxins and PCBs. However, many naturally occurring compounds also activate AhR. One such compound, 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE), was isolated from tissue and found to be potent in preliminary tests [J. Song, M. Clagett-Dame, R.E. Peterson, M.E. Hahn, W.M. Westler, R.R. Sicinski, H.F. DeLuca, Proc. Natl. Acad. Sci. USA 99 (2002) 14694-14699]. We have synthesized ITE and [(3)H]ITE and further evaluated its AhR activity in several in vitro and in vivo assays in comparison with the toxic ligand, TCDD. AhR in Hepa1c1c7 cell cytosol bound [(3)H]ITE with high affinity and the AhR.ITE complex formed in vitro bound dioxin response element (DRE) oligonucleotide as potently as TCDD.AhR. In cells treated with ITE, nuclear translocation of AhR, and induction of CYP1A1 protein and of a DRE-dependent luciferase reporter gene were observed. ITE administered to pregnant DRE-LacZ transgenic mice activated fetal AhR, observed as X-gal staining in the same sites as in TCDD-treated mice. However, unlike TCDD, ITE did not induce cleft palate or hydronephrosis. TCDD but not ITE induced thymic atrophy in young adult mice, but both ITE and TCDD caused similar loss of cells and alterations of cell profiles in cultured fetal thymi. These data demonstrate that ITE is a potent AhR agonist in cell extracts, cultured cells, and intact animals, but does not cause the toxicity associated with the more stable xenobiotic ligand, TCDD.

  4. A Potent Gelatinase Inhibitor with Anti-Tumor-Invasive Activity and its Metabolic Disposition

    PubMed Central

    Lee, Mijoon; Celenza, Giuseppe; Boggess, Bill; Blase, Jennifer; Shi, Qicun; Toth, Marta; Bernardo, M. Margarida; Wolter, William R.; Suckow, Mark A.; Hesek, Dusan; Noll, Bruce C.; Fridman, Rafael; Mobashery, Shahriar; Chang, Mayland

    2009-01-01

    Metastatic tumors lead to more than 90% fatality. Despite the importance of invasiveness of tumors to poor disease outcome, no anti-invasive compounds have been commercialized. We describe herein the synthesis and evaluation of 4-(4-(thiiranylmethylsulfonyl)phenoxy)-phenyl methane-sulfonate (compound 2) as a potent and selective inhibitor of gelatinases (matrix metalloproteinases-2 and -9), two enzymes implicated in invasiveness of tumors. It was demonstrated that compound 2 significantly attenuated the invasiveness of human fibrosarcoma cells (HT1080). The metabolism of compound 2 involved hydroxylation at the a-methylene, which generates sulfinic acid, thiirane ring-opening, followed by methylation and oxidation, and cysteine conjugation of both the thiirane and phenyl rings. PMID:19207421

  5. Synthesis and structure-activity relationships of novel arylpiperazines as potent antagonists of α1-adrenoceptor.

    PubMed

    Silva, Renata Oliveira; de Oliveira, Andressa Souza; Nunes Lemes, Laís Flávia; de Camargo Nascente, Luciana; Coelho do Nascimento Nogueira, Patrícia; Silveira, Edilberto R; Brand, Guilherme D; Vistoli, Giulio; Cilia, Antonio; Poggesi, Elena; Buccioni, Michela; Marucci, Gabriella; Bolognesi, Maria Laura; Romeiro, Luiz Antonio Soares

    2016-10-21

    Arylpiperazines 2-11 were synthesized, and their biological profiles at α1-adrenergic receptors (α1-ARs) assessed by binding assays in CHO cells expressing human cloned subtypes and by functional experiments in isolated rat vas deferens (α1A), spleen (α1B), and aorta (α1D). Modifications at the 1,3-benzodioxole and phenyl phamacophoric units resulted in the identification of a number of potent compounds (moderately selective with respect to the α1b-AR), in binding experiments. Notably, compound 7 (LDT451) showed a subnanomolar pKi of 9.41 towards α1a-AR. An encouragingly lower α1B-potency was a general trend for all the series of compounds, which showed α1A/D over α1B selectivity in functional assays. If adequately optimized, such peculiar selectivity could have relevance for a potential LUTS/BPH therapeutic application. PMID:27448917

  6. Discovery of highly potent acid ceramidase inhibitors with in vitro tumor chemosensitizing activity

    PubMed Central

    Realini, Natalia; Solorzano, Carlos; Pagliuca, Chiara; Pizzirani, Daniela; Armirotti, Andrea; Luciani, Rosaria; Costi, Maria Paola; Bandiera, Tiziano; Piomelli, Daniele

    2013-01-01

    The expression of acid ceramidase (AC) – a cysteine amidase that hydrolyses the proapoptotic lipid ceramide – is abnormally high in several human tumors, which is suggestive of a role in chemoresistance. Available AC inhibitors lack, however, the potency and drug-likeness necessary to test this idea. Here we show that the antineoplastic drug carmofur, which is used in the clinic to treat colorectal cancers, is a potent AC inhibitor and that this property is essential to its anti-proliferative effects. Modifications in the chemical scaffold of carmofur yield new AC inhibitors that act synergistically with standard antitumoral drugs to prevent cancer cell proliferation. These findings identify AC as an unexpected target for carmofur, and suggest that this molecule can be used as starting point for the design of novel chemosensitizing agents. PMID:23301156

  7. Discovery and Characterization of a Potent Interleukin-6 Binding Peptide with Neutralizing Activity In Vivo

    PubMed Central

    Ranganath, Sheila; Bhandari, Ashok; Avitahl-Curtis, Nicole; McMahon, Jaimee; Wachtel, Derek; Zhang, Jenny; Leitheiser, Christopher; Bernier, Sylvie G.; Liu, Guang; Tran, Tran T.; Celino, Herodion; Tobin, Jenny; Jung, Joon; Zhao, Hong; Glen, Katie E.; Graul, Chris; Griffin, Aliesha; Schairer, Wayne C.; Higgins, Carolyn; Reza, Tammi L.; Mowe, Eva; Rivers, Sam; Scott, Sonya; Monreal, Alex; Shea, Courtney; Bourne, Greg; Coons, Casey; Smith, Adaline; Tang, Kim; Mandyam, Ramya A.; Masferrer, Jaime; Liu, David; Patel, Dinesh V.; Fretzen, Angelika; Murphy, Craig A.; Milne, G. Todd; Smythe, Mark L.; Carlson, Kenneth E.

    2015-01-01

    Interleukin-6 (IL-6) is an important member of the cytokine superfamily, exerting pleiotropic actions on many physiological processes. Over-production of IL-6 is a hallmark of immune-mediated inflammatory diseases such as Castleman’s Disease (CD) and rheumatoid arthritis (RA). Antagonism of the interleukin IL-6/IL-6 receptor (IL-6R)/gp130 signaling complex continues to show promise as a therapeutic target. Monoclonal antibodies (mAbs) directed against components of this complex have been approved as therapeutics for both CD and RA. To potentially provide an additional modality to antagonize IL-6 induced pathophysiology, a peptide-based antagonist approach was undertaken. Using a combination of molecular design, phage-display, and medicinal chemistry, disulfide-rich peptides (DRPs) directed against IL-6 were developed with low nanomolar potency in inhibiting IL-6-induced pSTAT3 in U937 monocytic cells. Targeted PEGylation of IL-6 binding peptides resulted in molecules that retained their potency against IL-6 and had a prolongation of their pharmacokinetic (PK) profiles in rodents and monkeys. One such peptide, PN-2921, contained a 40 kDa polyethylene glycol (PEG) moiety and inhibited IL-6-induced pSTAT3 in U937 cells with sub-nM potency and possessed 23, 36, and 59 h PK half-life values in mice, rats, and cynomolgus monkeys, respectively. Parenteral administration of PN-2921 to mice and cynomolgus monkeys potently inhibited IL-6-induced biomarker responses, with significant reductions in the acute inflammatory phase proteins, serum amyloid A (SAA) and C-reactive protein (CRP). This potent, PEGylated IL-6 binding peptide offers a new approach to antagonize IL-6-induced signaling and associated pathophysiology. PMID:26555695

  8. Discovery and Characterization of a Potent Interleukin-6 Binding Peptide with Neutralizing Activity In Vivo.

    PubMed

    Ranganath, Sheila; Bhandari, Ashok; Avitahl-Curtis, Nicole; McMahon, Jaimee; Wachtel, Derek; Zhang, Jenny; Leitheiser, Christopher; Bernier, Sylvie G; Liu, Guang; Tran, Tran T; Celino, Herodion; Tobin, Jenny; Jung, Joon; Zhao, Hong; Glen, Katie E; Graul, Chris; Griffin, Aliesha; Schairer, Wayne C; Higgins, Carolyn; Reza, Tammi L; Mowe, Eva; Rivers, Sam; Scott, Sonya; Monreal, Alex; Shea, Courtney; Bourne, Greg; Coons, Casey; Smith, Adaline; Tang, Kim; Mandyam, Ramya A; Masferrer, Jaime; Liu, David; Patel, Dinesh V; Fretzen, Angelika; Murphy, Craig A; Milne, G Todd; Smythe, Mark L; Carlson, Kenneth E

    2015-01-01

    Interleukin-6 (IL-6) is an important member of the cytokine superfamily, exerting pleiotropic actions on many physiological processes. Over-production of IL-6 is a hallmark of immune-mediated inflammatory diseases such as Castleman's Disease (CD) and rheumatoid arthritis (RA). Antagonism of the interleukin IL-6/IL-6 receptor (IL-6R)/gp130 signaling complex continues to show promise as a therapeutic target. Monoclonal antibodies (mAbs) directed against components of this complex have been approved as therapeutics for both CD and RA. To potentially provide an additional modality to antagonize IL-6 induced pathophysiology, a peptide-based antagonist approach was undertaken. Using a combination of molecular design, phage-display, and medicinal chemistry, disulfide-rich peptides (DRPs) directed against IL-6 were developed with low nanomolar potency in inhibiting IL-6-induced pSTAT3 in U937 monocytic cells. Targeted PEGylation of IL-6 binding peptides resulted in molecules that retained their potency against IL-6 and had a prolongation of their pharmacokinetic (PK) profiles in rodents and monkeys. One such peptide, PN-2921, contained a 40 kDa polyethylene glycol (PEG) moiety and inhibited IL-6-induced pSTAT3 in U937 cells with sub-nM potency and possessed 23, 36, and 59 h PK half-life values in mice, rats, and cynomolgus monkeys, respectively. Parenteral administration of PN-2921 to mice and cynomolgus monkeys potently inhibited IL-6-induced biomarker responses, with significant reductions in the acute inflammatory phase proteins, serum amyloid A (SAA) and C-reactive protein (CRP). This potent, PEGylated IL-6 binding peptide offers a new approach to antagonize IL-6-induced signaling and associated pathophysiology. PMID:26555695

  9. Discovery of the First N-Hydroxycinnamamide-Based Histone Deacetylase 1/3 Dual Inhibitors with Potent Oral Antitumor Activity

    PubMed Central

    2015-01-01

    In our previous study, we designed and synthesized a novel series of N-hydroxycinnamamide-based HDAC inhibitors (HDACIs), among which the representative compound 14a exhibited promising HDACs inhibition and antitumor activity. In this current study, we report the development of a more potent class of N-hydroxycinnamamide-based HDACIs, using 14a as lead, among which, compound 11r gave IC50 values of 11.8, 498.1, 3.9, 2000.8, 5700.4, 308.2, and 900.4 nM for the inhibition of HDAC1, HDAC2, HDAC3, HDAC8, HDAC4, HDAC6, and HDAC11, exhibiting dual HDAC1/3 selectivity. Compounds 11e, 11r, 11w, and 11y showed excellent growth inhibition in multiple tumor cell lines. In vivo antitumor assay in U937 xenograft model identified compound 11r as a potent, orally active HDACI. To the best of our knowledge, this work constitutes the first report of oral active N-hydroxycinnamamide-based HDACIs with dual HDAC1/3 selectivity. PMID:24694055

  10. Structure-Activity Relationships of Bacillus cereus and Bacillus anthracis Dihydrofolate Reductase: toward the Identification of New Potent Drug Leads

    PubMed Central

    Joska, Tammy M.; Anderson, Amy C.

    2006-01-01

    New and improved therapeutics are needed for Bacillus anthracis, the etiological agent of anthrax. To date, antimicrobial agents have not been developed against the well-validated target dihydrofolate reductase (DHFR). In order to address whether DHFR inhibitors could have potential use as clinical agents against Bacillus, 27 compounds were screened against this enzyme from Bacillus cereus, which is identical to the enzyme from B. anthracis at the active site. Several 2,4-diamino-5-deazapteridine compounds exhibit submicromolar 50% inhibitory concentrations (IC50s). Four of the inhibitors displaying potency in vitro were tested in vivo and showed a marked growth inhibition of B. cereus; the most potent of these has MIC50 and minimum bactericidal concentrations at which 50% are killed of 1.6 μg/ml and 0.09 μg/ml, respectively. In order to illustrate structure-activity relationships for the classes of inhibitors tested, each of the 27 inhibitors was docked into homology models of the B. cereus and B. anthracis DHFR proteins, allowing the development of a rationale for the inhibition profiles. A combination of favorable interactions with the diaminopyrimidine and substituted phenyl rings explains the low IC50 values of potent inhibitors; steric interactions explain higher IC50 values. These experiments show that DHFR is a reasonable antimicrobial target for Bacillus anthracis and that there is a class of inhibitors that possess sufficient potency and antibacterial activity to suggest further development. PMID:17005826

  11. Ivermectin is a potent inhibitor of flavivirus replication specifically targeting NS3 helicase activity: new prospects for an old drug

    PubMed Central

    Mastrangelo, Eloise; Pezzullo, Margherita; De Burghgraeve, Tine; Kaptein, Suzanne; Pastorino, Boris; Dallmeier, Kai; de Lamballerie, Xavier; Neyts, Johan; Hanson, Alicia M.; Frick, David N.; Bolognesi, Martino; Milani, Mario

    2012-01-01

    Objectives Infection with yellow fever virus (YFV), the prototypic mosquito-borne flavivirus, causes severe febrile disease with haemorrhage, multi-organ failure and a high mortality. Moreover, in recent years the Flavivirus genus has gained further attention due to re-emergence and increasing incidence of West Nile, dengue and Japanese encephalitis viruses. Potent and safe antivirals are urgently needed. Methods Starting from the crystal structure of the NS3 helicase from Kunjin virus (an Australian variant of West Nile virus), we identified a novel, unexploited protein site that might be involved in the helicase catalytic cycle and could thus in principle be targeted for enzyme inhibition. In silico docking of a library of small molecules allowed us to identify a few selected compounds with high predicted affinity for the new site. Their activity against helicases from several flaviviruses was confirmed in in vitro helicase/enzymatic assays. The effect on the in vitro replication of flaviviruses was then evaluated. Results Ivermectin, a broadly used anti-helminthic drug, proved to be a highly potent inhibitor of YFV replication (EC50 values in the sub-nanomolar range). Moreover, ivermectin inhibited, although less efficiently, the replication of several other flaviviruses, i.e. dengue fever, Japanese encephalitis and tick-borne encephalitis viruses. Ivermectin exerts its effect at a timepoint that coincides with the onset of intracellular viral RNA synthesis, as expected for a molecule that specifically targets the viral helicase. Conclusions The well-tolerated drug ivermectin may hold great potential for treatment of YFV infections. Furthermore, structure-based optimization may result in analogues exerting potent activity against flaviviruses other than YFV. PMID:22535622

  12. Central domain of IL-33 is cleaved by mast cell proteases for potent activation of group-2 innate lymphoid cells.

    PubMed

    Lefrançais, Emma; Duval, Anais; Mirey, Emilie; Roga, Stéphane; Espinosa, Eric; Cayrol, Corinne; Girard, Jean-Philippe

    2014-10-28

    Interleukin-33 (IL-33) is an alarmin cytokine from the IL-1 family. IL-33 activates many immune cell types expressing the interleukin 1 receptor-like 1 (IL1RL1) receptor ST2, including group-2 innate lymphoid cells (ILC2s, natural helper cells, nuocytes), the major producers of IL-5 and IL-13 during type-2 innate immune responses and allergic airway inflammation. IL-33 is likely to play a critical role in asthma because the IL33 and ST2/IL1RL1 genes have been reproducibly identified as major susceptibility loci in large-scale genome-wide association studies. A better understanding of the mechanisms regulating IL-33 activity is thus urgently needed. Here, we investigated the role of mast cells, critical effector cells in allergic disorders, known to interact with ILC2s in vivo. We found that serine proteases secreted by activated mast cells (chymase and tryptase) generate mature forms of IL-33 with potent activity on ILC2s. The major forms produced by mast cell proteases, IL-33(95-270), IL-33(107-270), and IL-33(109-270), were 30-fold more potent than full-length human IL-33(1-270) for activation of ILC2s ex vivo. They induced a strong expansion of ILC2s and eosinophils in vivo, associated with elevated concentrations of IL-5 and IL-13. Murine IL-33 is also cleaved by mast cell tryptase, and a tryptase inhibitor reduced IL-33-dependent allergic airway inflammation in vivo. Our study identifies the central cleavage/activation domain of IL-33 (amino acids 66-111) as an important functional domain of the protein and suggests that interference with IL-33 cleavage and activation by mast cell and other inflammatory proteases could be useful to reduce IL-33-mediated responses in allergic asthma and other inflammatory diseases.

  13. Synthesis and Biological Evaluation of 3-Alkyl-1,5-Diaryl-1H-Pyrazoles as Rigid Analogues of Combretastatin A-4 with Potent Antiproliferative Activity

    PubMed Central

    Xu, Qile; Qi, Huan; Sun, Maolin; Zuo, Daiying; Jiang, Xuewei; Wen, Zhiyong; Wang, Zhiwei; Wu, Yingliang; Zhang, Weige

    2015-01-01

    A series of novel 3-alkyl-1,5-diaryl-1H-pyrazoles were synthesized as combretastatin A-4 (CA-4) analogues and evaluated for antiproliferative activity against three human cancer cell lines (SGC-7901, A549 and HT-1080). Most of the target compounds displayed moderate to potent antiproliferative activity, and 7k was found to be the most potent compound. Structure-activity relationships indicated that compounds with a trimethoxyphenyl A-ring at the N-1 position of the pyrazole skeleton were more potent than those with the A-ring at the C-5 position. Tubulin polymerization and immunostaining experiments revealed that 7k potently inhibited tubulin polymerization and disrupted tubulin microtubule dynamics in a manner similar to CA-4. Computational modelling demonstrated that the binding of 7k to the colchicine binding site on microtubules may involve a similar mode as CA-4. PMID:26061410

  14. Inhibition of constitutive signal transducer and activator of transcription 3 activation by novel platinum complexes with potent antitumor activity.

    PubMed

    Turkson, James; Zhang, Shumin; Palmer, Jay; Kay, Heidi; Stanko, Joseph; Mora, Linda B; Sebti, Said; Yu, Hua; Jove, Richard

    2004-12-01

    DNA-alkylating agents that are platinum complexes induce apoptotic responses and have wide application in cancer therapy. The potential for platinum compounds to modulate signal transduction events that contribute to their therapeutic outcome has not been extensively examined. Among the signal transducer and activator of transcription (STAT) proteins, Stat3 activity is frequently up-regulated in many human tumors. Various lines of evidence have established a causal role for aberrant Stat3 activity in malignant transformation and provided validation for its targeting in the development of small-molecule inhibitors as novel cancer therapeutics. We report here that platinum-containing compounds disrupt Stat3 signaling and suppress its biological functions. The novel platinum (IV) compounds, CPA-1, CPA-7, and platinum (IV) tetrachloride block Stat3 activity in vitro at low micromolar concentrations. In malignant cells that harbor constitutively activated Stat3, CPA-1, CPA-7, and platinum (IV) tetrachloride inhibit cell growth and induce apoptosis in a manner that reflects the attenuation of persistent Stat3 activity. By contrast, cells that do not contain persistent Stat3 activity are marginally affected or are not affected by these compounds. Moreover, CPA-7 induces the regression of mouse CT26 colon tumor, which correlates with the abrogation of persistent Stat3 activity in tumors. Thus, the modulation of oncogenic signal transduction pathways, such as Stat3, may be one of the key molecular mechanisms for the antitumor effects of platinum (IV)-containing complexes.

  15. Synthesis and antiviral activity of the carbocyclic analogue of the highly potent and selective anti-VZV bicyclo furano pyrimidines.

    PubMed

    Migliore, Marco D; Zonta, Nicola; McGuigan, Christopher; Henson, Geoffrey; Andrei, Graciela; Snoeck, Robert; Balzarini, Jan

    2007-12-27

    Carbocyclic nucleoside analogues are catabolically stable since they are resistant to phosphorolytic cleavage by pyrimidine nucleoside phosphorylase enzymes. The carbocyclic analogue (C-BCNA) of the highly potent and selective anti-VZV bicyclic nucleoside analogue (BCNA) 6-pentylphenylfuro[2,3-d]pyrimidine-2'-deoxyribose was synthesized using carbocyclic 2'-deoxyuridine as starting material. C-BCNA was found to be chemically more stable than the furano lead, but it was shown to be significantly less antivirally active than its parent nucleoside analogue. It was noted to have a 10-fold lower inhibitory activity against the VZV-encoded thymidine kinase. This reduction of activity may be attributed to the different conformation of the sugar and base, as predicted by computational studies and supported by NMR studies. However, other factors besides affinity for VZV-TK must account for the greatly reduced antiviral potency. PMID:18052321

  16. Synthesis and in vitro/in vivo Evaluation of the Antitrypanosomal Activity of 3-Bromoacivicin, a Potent CTP Synthetase Inhibitor

    PubMed Central

    Conti, Paola; Pinto, Andrea; Wong, Pui E; Major, Louise L; Tamborini, Lucia; Iannuzzi, Maria C; De Micheli, Carlo; Barrett, Michael P; Smith, Terry K

    2011-01-01

    Abstract The first convenient synthesis of enantiomerically pure (αS,5S)-α-amino-3-bromo-4,5-dihydroisoxazol-5-yl acetic acid (3-bromoacivicin) is described. We demonstrate that 3-bromoacivicin is a CTP synthetase inhibitor three times as potent as its 3-chloro analogue, the natural antibiotic acivicin. Because CTP synthetase was suggested to be a potential drug target in African trypanosomes, the in vitro/in vivo antitrypanosomal activity of 3-bromoacivicin was assessed in comparison with acivicin. Beyond expectation, we observed a 12-fold enhancement in the in vitro antitrypanosomal activity, while toxicity against mammalian cells remained unaffected. Despite its good in vitro activity and selectivity, 3-bromoacivicin proved to be trypanostatic and failed to completely eradicate the infection when tested in vivo at its maximum tolerable dose. PMID:21275056

  17. Urolithins, intestinal microbial metabolites of Pomegranate ellagitannins, exhibit potent antioxidant activity in a cell-based assay.

    PubMed

    Bialonska, Dobroslawa; Kasimsetty, Sashi G; Khan, Shabana I; Ferreira, Daneel

    2009-11-11

    Many health benefits of pomegranate products have been attributed to the potent antioxidant action of their tannin components, mainly punicalagins and ellagic acid. While moving through the intestines, ellagitannins are metabolized by gut bacteria into urolithins that readily enter systemic circulation. In this study, the antioxidant properties of seven urolithin derivatives were evaluated in a cell-based assay. This method is biologically more relevant because it reflects bioavailability of the test compound to the cells, and the antioxidant action is determined in the cellular environment. Our results showed that the antioxidant activity of urolithins was correlated with the number of hydroxy groups as well as the lipophilicity of the molecule. The most potent antioxidants are urolithins C and D with IC(50) values of 0.16 and 0.33 microM, respectively, when compared to IC(50) values of 1.1 and 1.4 microM of the parent ellagic acid and punicalagins, respectively. The dihydroxylated urolithin A showed weaker antioxidant activity, with an IC(50) value 13.6 microM, however, the potency was within the range of urolithin A plasma concentrations. Therefore, products of the intestinal microbial transformation of pomegranate ellagitannins may account for systemic antioxidant effects.

  18. The Spider Venom Peptide Lycosin-II Has Potent Antimicrobial Activity against Clinically Isolated Bacteria

    PubMed Central

    Wang, Yongjun; Wang, Ling; Yang, Huali; Xiao, Haoliang; Farooq, Athar; Liu, Zhonghua; Hu, Min; Shi, Xiaoliu

    2016-01-01

    Antimicrobial peptides have been accepted as excellent candidates for developing novel antibiotics against drug-resistant bacteria. Recent studies indicate that spider venoms are the source for the identification of novel antimicrobial peptides. In the present study, we isolated and characterized an antibacterial peptide named lycosin-II from the venom of the spider Lycosa singoriensis. It contains 21 amino acid residue lacking cysteine residues and forms a typical linear amphipathic and cationic α-helical conformation. Lycosin-II displays potent bacteriostatic effect on the tested drug-resistant bacterial strains isolated from hospital patients, including multidrug-resistant A. baumannii, which has presented a huge challenge for the infection therapy. The inhibitory ability of lycosin-II might derive from its binding to cell membrane, because Mg2+ could compete with the binding sites to reduce the bacteriostatic potency of lycosin-II. Our data suggest that lycosin-II might be a lead in the development of novel antibiotics for curing drug-resistant bacterial infections. PMID:27128941

  19. The Spider Venom Peptide Lycosin-II Has Potent Antimicrobial Activity against Clinically Isolated Bacteria.

    PubMed

    Wang, Yongjun; Wang, Ling; Yang, Huali; Xiao, Haoliang; Farooq, Athar; Liu, Zhonghua; Hu, Min; Shi, Xiaoliu

    2016-04-26

    Antimicrobial peptides have been accepted as excellent candidates for developing novel antibiotics against drug-resistant bacteria. Recent studies indicate that spider venoms are the source for the identification of novel antimicrobial peptides. In the present study, we isolated and characterized an antibacterial peptide named lycosin-II from the venom of the spider Lycosa singoriensis. It contains 21 amino acid residue lacking cysteine residues and forms a typical linear amphipathic and cationic α-helical conformation. Lycosin-II displays potent bacteriostatic effect on the tested drug-resistant bacterial strains isolated from hospital patients, including multidrug-resistant A. baumannii, which has presented a huge challenge for the infection therapy. The inhibitory ability of lycosin-II might derive from its binding to cell membrane, because Mg(2+) could compete with the binding sites to reduce the bacteriostatic potency of lycosin-II. Our data suggest that lycosin-II might be a lead in the development of novel antibiotics for curing drug-resistant bacterial infections.

  20. Preclinical evaluation of novel imidazoacridinone derivatives with potent activity against experimental colorectal cancer.

    PubMed Central

    Burger, A. M.; Double, J. A.; Konopa, J.; Bibby, M. C.

    1996-01-01

    Novel imidazoacridinone derivatives, C1310 and C1311, have been evaluated for their potential to inhibit tumour cell growth in vitro and in vivo. A cell line panel, including seven human and murine colon carcinoma cell lines and three in vivo models, was used. The compounds were found to be potent inhibitors of tumour cell growth with IC50 values ranging between 10 nM and 2 microM in human colon cancer cell lines. Statistically significant tumour growth delay (P < 0.01) was observed after a single intraperitoneal (i.p.) dose of C1311 (100 mg kg-1 body weight) in MAC15A, MAC29 murine and HT29 human adenocarcinomas of the colon. Rapid accumulation of fluorescence of both C1310 and C1311 was seen in the nuclei of HT29 human colon tumour cells in culture. C1311 was also found to bind into calf thymus DNA as shown by spectrophotometric titration and thermal denaturation and to cause early inhibition of thymidine incorporation in HT29 cells in vitro. The results of this study suggest that C1311 should be considered as a candidate for clinical development. Images Figure 3 PMID:8912531

  1. Potent inhibition of Hendra virus infection via RNA interference and poly I:C immune activation.

    PubMed

    McCaskill, Jana L; Marsh, Glenn A; Monaghan, Paul; Wang, Lin-Fa; Doran, Timothy; McMillan, Nigel A J

    2013-01-01

    Hendra virus (HeV) is a highly pathogenic zoonotic paramyxovirus that causes fatal disease in a wide range of species, including humans. HeV was first described in Australia in 1994, and has continued to re-emerge with increasing frequency. HeV is of significant concern to human health due to its high mortality rate, increasing emergence, absence of vaccines and limited post exposure therapies. Here we investigate the use of RNA interference (RNAi) based therapeutics targeting HeV in conjunction with the TLR3 agonist Poly I:C and show that they are potent inhibitors of HeV infection in vitro. We found that short interfering RNAs (siRNAs) targeting the abundantly expressed N, P and M genes of HeV caused over 95% reduction of HeV virus titre, protein and mRNA. Furthermore, we found that the combination of HeV targeting siRNA and Poly I:C had an additive effect in suppressing HeV infection. Our results demonstrate for the first time that RNAi and type I interferon stimulation are effective inhibitors of HeV replication in vitro and may provide an effective therapy for this highly lethal, zoonotic pathogen.

  2. Design, synthesis and molecular docking of α,β-unsaturated cyclohexanone analogous of curcumin as potent EGFR inhibitors with antiproliferative activity.

    PubMed

    Xu, Yun-Yun; Cao, Yi; Ma, Hailkuo; Li, Huan-Qiu; Ao, Gui-Zhen

    2013-01-15

    A type of novel α,β-unsaturated cyclohexanone analogous, which designed based on the curcumin core structure, have been discovered as potential EGFR inhibitors. These compounds exhibit potent antiproliferative activity in two human tumor cell lines (Hep G2 and B16-F10). Among them, compounds I(3) and I(12) displayed the most potent EGFR inhibitory activity (IC(50) = 0.43 μM and 1.54 μM, respectively). Molecular docking of I(12) into EGFR TK active site was also performed. This inhibitor nicely fitting the active site might well explain its excellent inhibitory activity.

  3. Sulfonic acid polymers: Highly potent inhibition of HIV-1 and HIV-2 reverse transcriptase and antiviral activity

    SciTech Connect

    Mohan, P.; Verma, S.; Tan, G.T.; Wickramasinghe, A.; Pezzuto, J.M.; Huges, S.H.; Baba, M.

    1993-12-31

    In an extension of the authors` work in the sulfonic acid polymer area they have evaluated the reverse transcriptase (RT) inhibitory activity of several varying molecular weight aromatic and aliphatic derivatives. All the polymers possess anti-HIV activity at doses that are non-toxic to the host cells and act by inhibiting viral adsorption. In the RT assay, poly(4-styrenesulfonic acid) exhibited highly potent inhibition with IC{sub 50} values of 0.0008 {mu}M and 0.0007 {mu}M for HIV-1 and HIV-2 RT respectively. The discovery of the anti-RT potential of these derivatives provides the impetus to investigate additional intervention strategies that are coupled with the facilitated cellular penetration of these agents.

  4. 2,9-Dimethyl-1,10-phenanthroline (neocuproine): a potent, copper-dependent cytotoxin with anti-tumor activity.

    PubMed

    Mohindru, A; Fisher, J M; Rabinovitz, M

    1983-12-01

    2,9-Dimethyl-1,10-phenanthroline (2,9-DMP), a copper-specific chelator, was a potent cytotoxin against L1210 cells in vitro; its activity was dependent upon available Cu2+ in the medium. Other divalent ions, Fe2+ and Zn2+, were ineffective as promoters of growth inhibition. As the copper chelate, a 4 microM solution produced a 4 log kill after a 1-hr incubation. This was in marked contrast to 1,10-phenanthroline, whose inhibition of cell growth was overcome by added Cu2+, Fe2+ and Zn2+. Cellular uptake of labeled 2,9-dimethyl-1,10-phenanthroline also required added Cu2+ in the medium. This transport was energy dependent, and the drug was concentrated over 200-fold by the cells. In preliminary evaluations, copper-2,9-DMP showed significant chemotherapeutic activity against the P388 murine lymphoma in vivo.

  5. (-)-Englerin A is a potent and selective activator of TRPC4 and TRPC5 calcium channels.

    PubMed

    Akbulut, Yasemin; Gaunt, Hannah J; Muraki, Katsuhiko; Ludlow, Melanie J; Amer, Mohamed S; Bruns, Alexander; Vasudev, Naveen S; Radtke, Lea; Willot, Matthieu; Hahn, Sven; Seitz, Tobias; Ziegler, Slava; Christmann, Mathias; Beech, David J; Waldmann, Herbert

    2015-03-16

    Current therapies for common types of cancer such as renal cell cancer are often ineffective and unspecific, and novel pharmacological targets and approaches are in high demand. Here we show the unexpected possibility for the rapid and selective killing of renal cancer cells through activation of calcium-permeable nonselective transient receptor potential canonical (TRPC) calcium channels by the sesquiterpene (-)-englerin A. This compound was found to be a highly efficient, fast-acting, potent, selective, and direct stimulator of TRPC4 and TRPC5 channels. TRPC4/5 activation through a high-affinity extracellular (-)-englerin A binding site may open up novel opportunities for drug discovery aimed at renal cancer.

  6. Discovery of novel, high potent, ABC type PTP1B inhibitors with TCPTP selectivity and cellular activity.

    PubMed

    Liu, Peihong; Du, Yongli; Song, Lianhua; Shen, Jingkang; Li, Qunyi

    2016-08-01

    Protein tyrosine phosphatase 1B (PTP1B) as a key negative regulator of both insulin and leptin receptor pathways has been an attractive therapeutic target for the treatment of type 2 diabetes mellitus (T2DM) and obesity. With the goal of enhancing potency and selectivity of the PTP1B inhibitors, a series of methyl salicylate derivatives as ABC type PTP1B inhibitors (P1-P7) were discovered. More importantly, compound P6 exhibited high potent inhibitory activity (IC50 = 50 nM) for PTP1B with 15-fold selectivity over T-cell PTPase (TCPTP). Further studies on cellular activities revealed that compound P6 could enhance insulin-mediated insulin receptor β (IRβ) phosphorylation and insulin-stimulated glucose uptake. PMID:27123900

  7. Pharmacological profile of the abeorphine 201-678, a potent orally active and long lasting dopamine agonist

    SciTech Connect

    Jaton, A.L.; Giger, R.K.A.; Vigouret, J.M.; Enz, A.; Frick, W.; Closse, A.; Markstein, R.

    1986-01-13

    The central dopaminergic effects of an abeorphine derivative 201-678 were compared to those of apomorphine and bromocriptine in different model systems. After oral administration, this compound induced contralateral turning in rats with 6-hydroxydopamine induced nigral lesions and exhibited strong anti-akinetic properties in rats with 6-hydroxydopamine induced hypothalamic lesions. It decreased dopamine metabolism in striatum and cortex, but did not modify noradrenaline and serotonin metabolism in the rat brain. 201-678 counteracted the in vivo increase of tyrosine hydroxylase activity induced by ..gamma..-butyrolactone. In vitro it stimulated DA-sensitive adenylate cyclase and inhibited acetylcholine release from rat striatal slices. This compound had high affinity for /sup 3/H-dopamine and /sup 3/H-clonidine binding sites. These results indicate that 201-678 is a potent, orally active dopamine agonist with a long duration of action. Furthermore it appears more selective than other dopaminergic drugs. 29 references, 5 figures, 3 tables.

  8. Identification of potent orally active factor Xa inhibitors based on conjugation strategy and application of predictable fragment recommender system.

    PubMed

    Ishihara, Tsukasa; Koga, Yuji; Iwatsuki, Yoshiyuki; Hirayama, Fukushi

    2015-01-15

    Anticoagulant agents have emerged as a promising class of therapeutic drugs for the treatment and prevention of arterial and venous thrombosis. We investigated a series of novel orally active factor Xa inhibitors designed using our previously reported conjugation strategy to boost oral anticoagulant effect. Structural optimization of anthranilamide derivative 3 as a lead compound with installation of phenolic hydroxyl group and extensive exploration of the P1 binding element led to the identification of 5-chloro-N-(5-chloro-2-pyridyl)-3-hydroxy-2-{[4-(4-methyl-1,4-diazepan-1-yl)benzoyl]amino}benzamide (33, AS1468240) as a potent factor Xa inhibitor with significant oral anticoagulant activity. We also reported a newly developed Free-Wilson-like fragment recommender system based on the integration of R-group decomposition with collaborative filtering for the structural optimization process.

  9. Preclinical pharmacology, antitumor activity and development of pharmacodynamic markers for the novel, potent AKT inhibitor CCT128930

    PubMed Central

    Yap, Timothy A.; Walton, Mike I.; Hunter, Lisa-Jane K.; Valenti, Melanie; de Haven Brandon, Alexis; Eve, Paul D.; Ruddle, Ruth; Heaton, Simon P.; Henley, Alan; Pickard, Lisa; Vijayaraghavan, Gowri; Caldwell, John J.; Thompson, Neil T.; Aherne, Wynne; Raynaud, Florence I.; Eccles, Suzanne A.; Workman, Paul; Collins, Ian; Garrett, Michelle D.

    2016-01-01

    AKT is frequently deregulated in cancer, making it an attractive anticancer drug target. CCT128930 is a novel ATP-competitive AKT inhibitor discovered using fragment and structure-based approaches. It is a potent, advanced lead pyrrolopyrimidine compound exhibiting selectivity for AKT over PKA, achieved by targeting a single amino acid difference. CCT128930 exhibited marked antiproliferative activity and inhibited the phosphorylation of a range of AKT substrates in multiple tumor cell lines in vitro, consistent with AKT inhibition. CCT128930 caused a G1 arrest in PTEN-null U87MG human glioblastoma cells, consistent with AKT pathway blockade. Pharmacokinetic studies established that potentially active concentrations of CCT128930 could be achieved in human tumor xenografts. Furthermore, CCT128930 also blocked the phosphorylation of several downstream AKT biomarkers in U87MG tumor xenografts, indicating AKT inhibition in vivo. Antitumor activity was observed with CCT128930 in U87MG and HER2-positive, PIK3CA-mutant BT474 human breast cancer xenografts, consistent with its pharmacokinetic and pharmacodynamic properties. A quantitative immunofluorescence assay to measure the phosphorylation and total protein expression of the AKT substrate PRAS40 in hair follicles is presented. Significant decreases in pThr246 PRAS40 occurred in CCT128930-treated mouse whisker follicles in vivo and human hair follicles treated ex vivo, with minimal changes in total PRAS40. In conclusion, CCT128930 is a novel, selective and potent AKT inhibitor, which blocks AKT activity in vitro and in vivo and induces marked antitumor responses. We have also developed a novel biomarker assay for the inhibition of AKT in human hair follicles, which is currently being employed in clinical trials. PMID:21191045

  10. Preclinical pharmacology, antitumor activity, and development of pharmacodynamic markers for the novel, potent AKT inhibitor CCT128930.

    PubMed

    Yap, Timothy A; Walton, Mike I; Hunter, Lisa-Jane K; Valenti, Melanie; de Haven Brandon, Alexis; Eve, Paul D; Ruddle, Ruth; Heaton, Simon P; Henley, Alan; Pickard, Lisa; Vijayaraghavan, Gowri; Caldwell, John J; Thompson, Neil T; Aherne, Wynne; Raynaud, Florence I; Eccles, Suzanne A; Workman, Paul; Collins, Ian; Garrett, Michelle D

    2011-02-01

    AKT is frequently deregulated in cancer, making it an attractive anticancer drug target. CCT128930 is a novel ATP-competitive AKT inhibitor discovered using fragment- and structure-based approaches. It is a potent, advanced lead pyrrolopyrimidine compound exhibiting selectivity for AKT over PKA, achieved by targeting a single amino acid difference. CCT128930 exhibited marked antiproliferative activity and inhibited the phosphorylation of a range of AKT substrates in multiple tumor cell lines in vitro, consistent with AKT inhibition. CCT128930 caused a G(1) arrest in PTEN-null U87MG human glioblastoma cells, consistent with AKT pathway blockade. Pharmacokinetic studies established that potentially active concentrations of CCT128930 could be achieved in human tumor xenografts. Furthermore, CCT128930 also blocked the phosphorylation of several downstream AKT biomarkers in U87MG tumor xenografts, indicating AKT inhibition in vivo. Antitumor activity was observed with CCT128930 in U87MG and HER2-positive, PIK3CA-mutant BT474 human breast cancer xenografts, consistent with its pharmacokinetic and pharmacodynamic properties. A quantitative immunofluorescence assay to measure the phosphorylation and total protein expression of the AKT substrate PRAS40 in hair follicles is presented. Significant decreases in pThr246 PRAS40 occurred in CCT128930-treated mouse whisker follicles in vivo and human hair follicles treated ex vivo, with minimal changes in total PRAS40. In conclusion, CCT128930 is a novel, selective, and potent AKT inhibitor that blocks AKT activity in vitro and in vivo and induces marked antitumor responses. We have also developed a novel biomarker assay for the inhibition of AKT in human hair follicles, which is currently being used in clinical trials. PMID:21191045

  11. Identification of Tetraazacyclic Compounds as Novel Potent Inhibitors Antagonizing RORγt Activity and Suppressing Th17 Cell Differentiation

    PubMed Central

    Ding, Qingfeng; Zhao, Mei; Yu, Bolan; Bai, Chuan; Huang, Zhaofeng

    2015-01-01

    CD4+ T-helper cells that produce interleukin-17 (Th17 cells) are characterized as pathological T-helper cells in autoimmune diseases. Differentiation of human and mouse Th17 cells requires a key transcription regulator, retinoic acid receptor-related orphan receptor γt (RORγt), which is a potential therapeutic target for autoimmune diseases. To develop a therapeutic agent for Th17-mediated autoimmune diseases, we have established a high-throughput screening (HTS) assay for candidate screening, in which the luciferase activity in RORγt-LBD positive and negative Jurkat cells were analyzed to evaluate induction of RORγt activity by compounds. This technique was applied to screen a commercially-available drug-like chemical compound library (Enamine) which contains 20155 compounds. The screening identified 17 compounds that can inhibit RORγt function in the HTS screen system. Of these, three tetraazacyclic compounds can potently inhibit RORγt activity, and suppress Th17 differentiation and IL-17 production. These three candidate compounds could significantly attenuate the expression of the Il17a by 65%- 90%, and inhibit IL-17A secretion by 47%, 63%, and 74%, respectively. These compounds also exhibited a potent anti-RORγt activity, with EC50 values of 0.25 μM, 0.67 μM and 2.6 μM, respectively. Our data demonstrated the feasibility of targeting the RORγt to inhibit Th17 cell differentiation and function with these tetraazacyclic compounds, and the potential to improve the structure of these compounds for autoimmune diseases therapeutics. PMID:26368822

  12. A novel immunomodulatory hemocyanin from the limpet Fissurella latimarginata promotes potent anti-tumor activity in melanoma.

    PubMed

    Arancibia, Sergio; Espinoza, Cecilia; Salazar, Fabián; Del Campo, Miguel; Tampe, Ricardo; Zhong, Ta-Ying; De Ioannes, Pablo; Moltedo, Bruno; Ferreira, Jorge; Lavelle, Ed C; Manubens, Augusto; De Ioannes, Alfredo E; Becker, María Inés

    2014-01-01

    Hemocyanins, the huge oxygen-transporting glycoproteins of some mollusks, are used as immunomodulatory proteins with proven anti-cancer properties. The biodiversity of hemocyanins has promoted interest in identifying new anti-cancer candidates with improved immunological properties. Hemocyanins promote Th1 responses without known side effects, which make them ideal for long-term sustained treatment of cancer. In this study, we evaluated a novel hemocyanin from the limpet/gastropod Fissurella latimarginata (FLH). This protein has the typical hollow, cylindrical structure of other known hemocyanins, such as the keyhole limpet hemocyanin (KLH) and the Concholepas hemocyanin (CCH). FLH, like the KLH isoforms, is composed of a single type of polypeptide with exposed N- and O-linked oligosaccharides. However, its immunogenicity was significantly greater than that of KLH and CCH, as FLH induced a stronger humoral immune response and had more potent anti-tumor activity, delaying tumor growth and increasing the survival of mice challenged with B16F10 melanoma cells, in prophylactic and therapeutic settings. Additionally, FLH-treated mice demonstrated increased IFN-γ production and higher numbers of tumor-infiltrating CD4(+) lymphocytes. Furthermore, in vitro assays demonstrated that FLH, but not CCH or KLH, stimulated the rapid production of pro-inflammatory cytokines (IL-6, IL-12, IL-23 and TNF-α) by dendritic cells, triggering a pro-inflammatory milieu that may explain its enhanced immunological activity. Moreover, this effect was abolished when deglycosylated FLH was used, suggesting that carbohydrates play a crucial role in the innate immune recognition of this protein. Altogether, our data demonstrate that FLH possesses increased anti-tumor activity in part because it activates a more potent innate immune response in comparison to other known hemocyanins. In conclusion, FLH is a potential new marine adjuvant for immunization and possible cancer immunotherapy.

  13. A Novel Immunomodulatory Hemocyanin from the Limpet Fissurella latimarginata Promotes Potent Anti-Tumor Activity in Melanoma

    PubMed Central

    Arancibia, Sergio; Espinoza, Cecilia; Salazar, Fabián; Del Campo, Miguel; Tampe, Ricardo; Zhong, Ta-Ying; De Ioannes, Pablo; Moltedo, Bruno; Ferreira, Jorge; Lavelle, Ed C.; Manubens, Augusto; De Ioannes, Alfredo E.; Becker, María Inés

    2014-01-01

    Hemocyanins, the huge oxygen-transporting glycoproteins of some mollusks, are used as immunomodulatory proteins with proven anti-cancer properties. The biodiversity of hemocyanins has promoted interest in identifying new anti-cancer candidates with improved immunological properties. Hemocyanins promote Th1 responses without known side effects, which make them ideal for long-term sustained treatment of cancer. In this study, we evaluated a novel hemocyanin from the limpet/gastropod Fissurella latimarginata (FLH). This protein has the typical hollow, cylindrical structure of other known hemocyanins, such as the keyhole limpet hemocyanin (KLH) and the Concholepas hemocyanin (CCH). FLH, like the KLH isoforms, is composed of a single type of polypeptide with exposed N- and O-linked oligosaccharides. However, its immunogenicity was significantly greater than that of KLH and CCH, as FLH induced a stronger humoral immune response and had more potent anti-tumor activity, delaying tumor growth and increasing the survival of mice challenged with B16F10 melanoma cells, in prophylactic and therapeutic settings. Additionally, FLH-treated mice demonstrated increased IFN-γ production and higher numbers of tumor-infiltrating CD4+ lymphocytes. Furthermore, in vitro assays demonstrated that FLH, but not CCH or KLH, stimulated the rapid production of pro-inflammatory cytokines (IL-6, IL-12, IL-23 and TNF-α) by dendritic cells, triggering a pro-inflammatory milieu that may explain its enhanced immunological activity. Moreover, this effect was abolished when deglycosylated FLH was used, suggesting that carbohydrates play a crucial role in the innate immune recognition of this protein. Altogether, our data demonstrate that FLH possesses increased anti-tumor activity in part because it activates a more potent innate immune response in comparison to other known hemocyanins. In conclusion, FLH is a potential new marine adjuvant for immunization and possible cancer immunotherapy. PMID

  14. Thusin, a Novel Two-Component Lantibiotic with Potent Antimicrobial Activity against Several Gram-Positive Pathogens.

    PubMed

    Xin, Bingyue; Zheng, Jinshui; Liu, Hualin; Li, Junhua; Ruan, Lifang; Peng, Donghai; Sajid, Muhammad; Sun, Ming

    2016-01-01

    Due to the rapidly increasing prevalence of multidrug-resistant bacterial strains, the need for new antimicrobial drugs to treat infections has become urgent. Bacteriocins, which are antimicrobial peptides of bacterial origin, are considered potential alternatives to conventional antibiotics and have attracted widespread attention in recent years. Among these bacteriocins, lantibiotics, especially two-component lantibiotics, exhibit potent antimicrobial activity against some clinically relevant Gram-positive pathogens and have potential applications in the pharmaceutical industry. In this study, we characterized a novel two-component lantibiotic termed thusin that consists of Thsα, Thsβ, and Thsβ' (mutation of Thsβ, A14G) and that was isolated from a B. thuringiensis strain BGSC 4BT1. Thsα and Thsβ (or Thsβ') exhibit optimal antimicrobial activity at a 1:1 ratio and act sequentially to affect target cells, and they are all highly thermostable (100°C for 30 min) and pH tolerant (pH 2.0 to 9.0). Thusin shows remarkable efficacy against all tested Gram-positive bacteria and greater activities than two known lantibiotics thuricin 4A-4 and ticin A4, and one antibiotic vancomycin against various bacterial pathogens (Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus (MRSA), Staphylococcus sciuri, Enterococcus faecalis, and Streptococcus pneumoniae). Moreover, thusin is also able to inhibit the outgrowth of B. cereus spores. The potent antimicrobial activity of thusin against some Gram-positive pathogens indicates that it has potential for the development of new drugs. PMID:27486447

  15. Thusin, a Novel Two-Component Lantibiotic with Potent Antimicrobial Activity against Several Gram-Positive Pathogens

    PubMed Central

    Xin, Bingyue; Zheng, Jinshui; Liu, Hualin; Li, Junhua; Ruan, Lifang; Peng, Donghai; Sajid, Muhammad; Sun, Ming

    2016-01-01

    Due to the rapidly increasing prevalence of multidrug-resistant bacterial strains, the need for new antimicrobial drugs to treat infections has become urgent. Bacteriocins, which are antimicrobial peptides of bacterial origin, are considered potential alternatives to conventional antibiotics and have attracted widespread attention in recent years. Among these bacteriocins, lantibiotics, especially two-component lantibiotics, exhibit potent antimicrobial activity against some clinically relevant Gram-positive pathogens and have potential applications in the pharmaceutical industry. In this study, we characterized a novel two-component lantibiotic termed thusin that consists of Thsα, Thsβ, and Thsβ' (mutation of Thsβ, A14G) and that was isolated from a B. thuringiensis strain BGSC 4BT1. Thsα and Thsβ (or Thsβ') exhibit optimal antimicrobial activity at a 1:1 ratio and act sequentially to affect target cells, and they are all highly thermostable (100°C for 30 min) and pH tolerant (pH 2.0 to 9.0). Thusin shows remarkable efficacy against all tested Gram-positive bacteria and greater activities than two known lantibiotics thuricin 4A-4 and ticin A4, and one antibiotic vancomycin against various bacterial pathogens (Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus (MRSA), Staphylococcus sciuri, Enterococcus faecalis, and Streptococcus pneumoniae). Moreover, thusin is also able to inhibit the outgrowth of B. cereus spores. The potent antimicrobial activity of thusin against some Gram-positive pathogens indicates that it has potential for the development of new drugs. PMID:27486447

  16. Thusin, a Novel Two-Component Lantibiotic with Potent Antimicrobial Activity against Several Gram-Positive Pathogens.

    PubMed

    Xin, Bingyue; Zheng, Jinshui; Liu, Hualin; Li, Junhua; Ruan, Lifang; Peng, Donghai; Sajid, Muhammad; Sun, Ming

    2016-01-01

    Due to the rapidly increasing prevalence of multidrug-resistant bacterial strains, the need for new antimicrobial drugs to treat infections has become urgent. Bacteriocins, which are antimicrobial peptides of bacterial origin, are considered potential alternatives to conventional antibiotics and have attracted widespread attention in recent years. Among these bacteriocins, lantibiotics, especially two-component lantibiotics, exhibit potent antimicrobial activity against some clinically relevant Gram-positive pathogens and have potential applications in the pharmaceutical industry. In this study, we characterized a novel two-component lantibiotic termed thusin that consists of Thsα, Thsβ, and Thsβ' (mutation of Thsβ, A14G) and that was isolated from a B. thuringiensis strain BGSC 4BT1. Thsα and Thsβ (or Thsβ') exhibit optimal antimicrobial activity at a 1:1 ratio and act sequentially to affect target cells, and they are all highly thermostable (100°C for 30 min) and pH tolerant (pH 2.0 to 9.0). Thusin shows remarkable efficacy against all tested Gram-positive bacteria and greater activities than two known lantibiotics thuricin 4A-4 and ticin A4, and one antibiotic vancomycin against various bacterial pathogens (Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus (MRSA), Staphylococcus sciuri, Enterococcus faecalis, and Streptococcus pneumoniae). Moreover, thusin is also able to inhibit the outgrowth of B. cereus spores. The potent antimicrobial activity of thusin against some Gram-positive pathogens indicates that it has potential for the development of new drugs.

  17. Discovery of Highly Potent p53-MDM2 Antagonists and Structural Basis for Anti-Acute Myeloid Leukemia Activities

    PubMed Central

    2015-01-01

    The inhibition of p53-MDM2 interaction is a promising new approach to non-genotoxic cancer treatment. A potential application for drugs blocking the p53-MDM2 interaction is acute myeloid leukemia (AML) due to the occurrence of wild type p53 (wt p53) in the majority of patients. Although there are very promising preclinical results of several p53-MDM2 antagonists in early development, none of the compounds have yet proven the utility as a next generation anticancer agent. Herein we report the design, synthesis and optimization of YH239-EE (ethyl ester of the free carboxylic acid compound YH239), a potent p53-MDM2 antagonizing and apoptosis-inducing agent characterized by a number of leukemia cell lines as well as patient-derived AML blast samples. The structural basis of the interaction between MDM2 (the p53 receptor) and YH239 is elucidated by a co-crystal structure. YH239-EE acts as a prodrug and is the most potent compound that induces apoptosis in AML cells and patient samples. The observed superior activity compared to reference compounds provides the preclinical basis for further investigation and progression of YH239-EE. PMID:24405416

  18. Structure-Based Design of Potent Bcl-2/Bcl-xL Inhibitors with Strong in Vivo Antitumor Activity

    SciTech Connect

    Zhou, Haibin; Aguilar, Angelo; Chen, Jianfang; Bai, Longchuan; Liu, Liu; Meagher, Jennifer L.; Yang, Chao-Yie; McEachern, Donna; Cong, Xin; Stuckey, Jeanne A.; Wang, Shaomeng

    2012-08-21

    Bcl-2 and Bcl-xL are key apoptosis regulators and attractive cancer therapeutic targets. We have designed and optimized a class of small-molecule inhibitors of Bcl-2 and Bcl-xL containing a 4,5-diphenyl-1H-pyrrole-3-carboxylic acid core structure. A 1.4 {angstrom} resolution crystal structure of a lead compound, 12, complexed with Bcl-xL has provided a basis for our optimization. The most potent compounds, 14 and 15, bind to Bcl-2 and Bcl-xL with subnanomolar K{sub i} values and are potent antagonists of Bcl-2 and Bcl-xL in functional assays. Compounds 14 and 15 inhibit cell growth with low nanomolar IC{sub 50} values in multiple small-cell lung cancer cell lines and induce robust apoptosis in cancer cells at concentrations as low as 10 nM. Compound 14 also achieves strong antitumor activity in an animal model of human cancer.

  19. Characterization of SR 121463A, a highly potent and selective, orally active vasopressin V2 receptor antagonist.

    PubMed Central

    Serradeil-Le Gal, C; Lacour, C; Valette, G; Garcia, G; Foulon, L; Galindo, G; Bankir, L; Pouzet, B; Guillon, G; Barberis, C; Chicot, D; Jard, S; Vilain, P; Garcia, C; Marty, E; Raufaste, D; Brossard, G; Nisato, D; Maffrand, J P; Le Fur, G

    1996-01-01

    SR 121463A, a potent and selective, orally active, nonpeptide vasopressin V2 receptor antagonist, has been characterized in several in vitro and in vivo models. This compound displayed highly competitive and selective affinity for V2 receptors in rat, bovine and human kidney (0.6 < or = Ki [nM] < or = 4.1). In this latter preparation, SR 121463A potently antagonized arginine vasopressin (AVP)-stimulated adenylyl cyclase activity (Ki = 0.26+/-0.04 nM) without any intrinsic agonistic effect. In autoradiographic experiments performed in rat kidney sections, SR 121463A displaced [3H]AVP labeling especially in the medullo-papillary region and confirmed that it is a suitable tool for mapping V2 receptors. In comparison, the nonpeptide V2 antagonist, OPC-31260, showed much lower affinity for animal and human renal V2 receptors and lower efficacy to inhibit vasopressin-stimulated adenylyl cyclase (Ki in the 10 nanomolar range). Moreover, OPC-31260 exhibited a poor V2 selectivity profile and can be considered as a V2/V1a ligand. In normally hydrated conscious rats, SR 121463A induced powerful aquaresis after intravenous (0.003-0.3 mg/kg) or oral (0.03-10 mg/kg) administration. The effect was dose-dependent and lasted about 6 hours at the dose of 3 mg/kg p.o. OPC-31260 had a similar aquaretic profile but with markedly lower oral efficacy. The action of SR 121463A was purely aquaretic with no changes in urine Na+ and K+ excretions unlike that of known diuretic agents such as furosemide or hydrochlorothiazide. In addition, no antidiuretic properties have been detected with SR 121463A in vasopressin-deficient Brattleboro rats. Thus, SR 121463A is the most potent and selective, orally active V2 antagonist yet described and could be a powerful tool for exploring V2 receptors and the therapeutical usefulness of V2 blocker aquaretic agents in water-retaining diseases. PMID:8981918

  20. Synthesis, cellular uptake and structure-activity relationships for potent cytotoxic trichloridoiridium(III) polypyridyl complexes.

    PubMed

    Scharwitz, Michael A; Ott, Ingo; Gust, Ronald; Kromm, Anna; Sheldrick, William S

    2008-08-01

    The complexes fac-[IrCl(3)(DMSO)(pp)] 1a-5a may be prepared by stepwise reaction of IrCl(3) x 3H(2)O with the appropriate polypyridyl ligand (pp=bpy, phen, dpq, dppz, dppn) and DMSO in CH(3)OH solution in the dark. The fac isomers of 1a-5a are stable in light-protected CD(2)Cl(2) solution but, with the exception of 5a, isomerize rapidly to a mixture of the fac and mer isomers in the presence of light. In contrast, solutions of the fac isomers in the polar solvents D(2)O and CD(3)OD are stable under such conditions. The isomer mer-[IrCl(3)(DMSO-kappa S)(phen)] 2b was, however, isolated by slow evaporation of an H(2)O/CH(3)OH solution of 2a and characterized by X-ray structural analysis. UV/Vis and CD studies of the interaction of 1a-5a with calf thymus DNA are in accordance with an effective absence of intercalation. (1)H NMR studies indicate that the complexes react slowly with compounds containing soft S donor atoms (e. g. N-acetylmethionine) but do not react with the guanine base of 5'-GMP(2-). The complexes 2a-5a are potent in vitro cytotoxic agents toward the human cell lines MCF-7 and HT-29 and their IC(50) values are dependent on the size of the polypyridyl ligand in the order phen, dpq>dppz>dppn. For instance IC(50) values of 5.5 (0.9), 0.8 (0.3) and 0.21 (0.11)microM were established for 3a-5a against MCF-7 cells and 6.1 (0.7), 1.5 (0.2) and 1.3 (0.4)microM against HT-29 cells. These values correlate with the cellular uptake efficiency which, on exposure to 10 microM solutions, reaches its highest levels (19.3(0.8) and 37.4(8.9) ng Ir/mg protein for MCF-7 and HT-29, respectively) for the dppn compound 5a. PMID:18472166

  1. Novel 1H-imidazol-2-amine derivatives as potent and orally active vascular adhesion protein-1 (VAP-1) inhibitors for diabetic macular edema treatment.

    PubMed

    Inoue, Takayuki; Morita, Masataka; Tojo, Takashi; Nagashima, Akira; Moritomo, Ayako; Miyake, Hiroshi

    2013-07-01

    Novel thiazole derivatives were synthesized and evaluated as vascular adhesion protein-1 (VAP-1) inhibitors. Although we previously identified a compound (2) with potent VAP-1 inhibitory activity in rats, the human activity was relatively weak. Here, to improve the human VAP-1 inhibitory activity of compound 2, we first evaluated the structure-activity relationships of guanidine bioisosteres as simple small molecules and identified a 1H-benzimidazol-2-amine (5) with potent activity compared to phenylguanidine (1). Based on the structure of compound 5, we synthesized a highly potent VAP-1 inhibitor (37b; human IC50=0.019 μM, rat IC50=0.0051 μM). Orally administered compound 37b also markedly inhibited ocular permeability in streptozotocin-induced diabetic rats after oral administration, suggesting it is a promising compound for the treatment of diabetic macular edema.

  2. Hypervalent iodine compounds as potent antibacterial agents against ice nucleation active (INA) Pseudomonas syringae.

    PubMed

    Menkissoglu-Spiroudi, U; Karamanoli, K; Spyroudis, S; Constantinidou, H I

    2001-08-01

    Twenty-three hypervalent iodine compounds belonging to aryliodonium salts, 1, aryliodonium ylides, 2, and (diacyloxyiodo)arenes, 3, were tested for their antibacterial activities against ice nucleation active (INA) Pseudomonas syringae, and the MIC and EC(50) values were determined. All of the compounds examined caused a dose-dependent decrease in bacterial growth rates. Aryliodonium salts, especially those with electron-withdrawing groups, exhibit higher antibacterial activities with MIC = 8-16 ppm, whereas the nature of the anion does not seem to affect the activities of the diaryliodonium salts. PMID:11513659

  3. Novel oxime-bearing coumarin derivatives act as potent Nrf2/ARE activators in vitro and in mouse model.

    PubMed

    Chang, Ken-Ming; Chen, Huang-Hui; Wang, Tai-Chi; Chen, I-Li; Chen, Yu-Tsen; Yang, Shyh-Chyun; Chen, Yeh-Long; Chang, Hsin-Huei; Huang, Chih-Hsiang; Chang, Jang-Yang; Shih, Chuan; Kuo, Ching-Chuan; Tzeng, Cherng-Chyi

    2015-12-01

    We have designed and synthesized certain novel oxime- and amide-bearing coumarin derivatives as nuclear factor erythroid 2 p45-related factor 2 (Nrf2) activators. The potency of these compounds was measured by antioxidant responsive element (ARE)-driven luciferase activity, level of Nrf2-related cytoprotective genes and proteins, and antioxidant activity. Among them, (Z)-3-(2-(hydroxyimino)-2-phenylethoxy)-2H-chromen-2-one (17a) was the most active, and more potent than the positive t-BHQ in the induction of ARE-driven luciferase activity. Exposure of HSC-3 cells to various concentrations of 17a strongly increased Nrf2 nuclear translocation and the expression level of Nrf2-mediated cytoprotective proteins in a concentration-dependent manner. HSC-3 cells pretreated with 17a significantly reduced t-BOOH-induced oxidative stress. In the animal experiment, Nrf2-mediated cytoprotective proteins, such as aldo-keto reductase 1 subunit C-1 (AKR1C1), glutathione reductase (GR), and heme oxygenase (HO-1), were obviously elevated in the liver of 17a-treated mice than that of control. These results suggested that novel oxime-bearing coumarin 17a is able to activate Nrf2/ARE pathway in vivo and are therefore seen as a promising candidate for further investigation.

  4. Structurally well-defined macrophage activating factor derived from vitamin D3-binding protein has a potent adjuvant activity for immunization.

    PubMed

    Yamamoto, N; Naraparaju, V R

    1998-06-01

    Freund's adjuvant produced severe inflammation that augments development of antibodies. Thus, mixed administration of antigens with adjuvant was not required as long as inflammation was induced in the hosts. Since macrophage activation for phagocytosis and antigen processing is the first step of antibody development, inflammation-primed macrophage activation plays a major role in immune development. Therefore, macrophage activating factor should act as an adjuvant for immunization. The inflammation-primed macrophage activation process is the major macrophage activating cascade that requires participation of serum vitamin D3-binding protein (DBP; human DBP is known as Gc protein) and glycosidases of B and T lymphocytes. Stepwise incubation of Gc protein with immobilized beta-galactosidase and sialidase efficiently generated the most potent macrophage activating factor (designated GcMAF) we have ever encountered. Administration of GcMAF (20 or 100 pg/mouse) resulted in stimulation of the progenitor cells for extensive mitogenesis and activation of macrophages. Administration of GcMAF (100 pg/mouse) along with immunization of mice with sheep red blood cells (SRBC) produced a large number of anti-SRBC antibody secreting splenic cells in 2-4 days. Thus, GcMAF has a potent adjuvant activity for immunization. Although malignant tumours are poorly immunogenic, 4 days after GcMAF-primed immunization of mice with heat-killed Ehrlich ascites tumour cells, the ascites tumour was no longer transplantable in these mice. PMID:9682967

  5. Water extracts of cinnamon and clove exhibits potent inhibition of protein glycation and anti-atherosclerotic activity in vitro and in vivo hypolipidemic activity in zebrafish.

    PubMed

    Jin, Seori; Cho, Kyung-Hyun

    2011-07-01

    Advanced glycation end products contribute to the pathogenesis of diabetic complications and atherosclerosis. Aqueous extracts of ground pepper, cinnamon, rosemary, ginger, and clove were analyzed and tested for anti-atherosclerotic activity in vitro and in vivo using hypercholesterolemic zebrafish. Cinnamon and clove extracts (at final 10 μg/mL) had the strongest anti-glycation and antioxidant activity in this study. Cinnamon and clove had the strongest inhibition of activity against copper-mediated low-density lipoprotein (LDL) oxidation and LDL phagocytosis by macrophages. Cinnamon or clove extracts had potent cholesteryl ester transfer protein (CETP) inhibitory activity in a concentration-dependent manner. They exhibited hypolipidemic activity in a hypercholesterolemic zebrafish model; the clove extract-treated group had a 68% and 80% decrease in serum cholesterol and TG levels, respectively. The clove extract-fed group had the smallest increase in body weight and height and the strongest antioxidant activity following a 5-week high cholesterol diet. Hydrophilic ingredients of cinnamon and clove showed potent activities to suppress the incidence of atherosclerosis and diabetes via strong antioxidant potential, prevention of apoA-I glycation and LDL-phagocytosis, inhibition of CETP, and hypolipidemic activity. These results suggest the potential to develop a new functional dietary agent to treat chronic metabolic diseases, such as hyperlipidemia and diabetes.

  6. Halichoblelide D, a New Elaiophylin Derivative with Potent Cytotoxic Activity from Mangrove-Derived Streptomyces sp. 219807.

    PubMed

    Han, Ying; Tian, Erli; Xu, Dongbo; Ma, Min; Deng, Zixin; Hong, Kui

    2016-07-25

    During our search for interesting bioactive secondary metabolites from mangrove actinomycetes, the strain Streptomyces sp. 219807 which produced a high elaiophylin yield of 4486 mg/L was obtained. A new elaiophylin derivative, halichoblelide D (1), along with seven known analogues 2-8 was isolated and identified from the culture broth. Their chemical structures were determined by detailed analysis of 1D and 2D NMR and HRMS data. The absolute configuration of halichoblelide D (1) was confirmed by comparing the CD spectrum with those of the reported analogues. Compounds 1-7 exhibited potent cytotoxic activities against HeLa and MCF-7 cells with IC50 values ranging from 0.19 to 2.12 μM.

  7. Halichoblelide D, a New Elaiophylin Derivative with Potent Cytotoxic Activity from Mangrove-Derived Streptomyces sp. 219807.

    PubMed

    Han, Ying; Tian, Erli; Xu, Dongbo; Ma, Min; Deng, Zixin; Hong, Kui

    2016-01-01

    During our search for interesting bioactive secondary metabolites from mangrove actinomycetes, the strain Streptomyces sp. 219807 which produced a high elaiophylin yield of 4486 mg/L was obtained. A new elaiophylin derivative, halichoblelide D (1), along with seven known analogues 2-8 was isolated and identified from the culture broth. Their chemical structures were determined by detailed analysis of 1D and 2D NMR and HRMS data. The absolute configuration of halichoblelide D (1) was confirmed by comparing the CD spectrum with those of the reported analogues. Compounds 1-7 exhibited potent cytotoxic activities against HeLa and MCF-7 cells with IC50 values ranging from 0.19 to 2.12 μM. PMID:27463707

  8. Tolyporphin: a natural product from cyanobacteria with potent photosensitizing activity against tumor cells in vitro and in vivo.

    PubMed

    Morlière, P; Mazière, J C; Santus, R; Smith, C D; Prinsep, M R; Stobbe, C C; Fenning, M C; Golberg, J L; Chapman, J D

    1998-08-15

    Tolyporphin (TP), a porphyrin extracted from cyanobacteria, was found to be a very potent photosensitizer of EMT-6 tumor cells grown both in vitro as suspensions or monolayers and in vivo in tumors implanted on the backs of C.B17/Icr severe combined immunodeficient mice. Thus, during photodynamic treatment (PDT) of EMT-6 tumor cells in vitro, the photokilling effectiveness of TP measured as the product of the reciprocal of D50 (the light dose necessary to kill 50% of cells) and the concentration of TP is approximately 5000 times higher than that of Photofrin II (PII), the only PDT photosensitizer thus far approved for clinical trials. TP almost exclusively localizes in the perinuclear region and specifically in the endoplasmic reticulum (ER), as shown by microspectrofluorometry on single living EMT-6 cells costained with the ER and/or Golgi fluorescent vital probes, 3,3'-dihexyloxacarbocyanine iodide and N-[4,4-difluoro-(5,7-dimethyl-BODIPY)-1-pentanoyl]-D-erythro-sphin gosine (Molecular Probes, Eugene, OR). As a result, the singlet oxygen-mediated photodynamic activity of TP induces an effective inactivation of the acyl CoA:cholesterol-O-acyltransferase, a sensitive marker of ER membrane integrity and alterations of the nuclear membrane. In vivo, with the EMT-6 mouse tumor model, an exceptional effectiveness is also observed as compared to that of PII and other second generation photosensitizers of the pheophorbide class, which are themselves much more potent than PII. The outstanding PDT activity of TP observed in vivo may be due to its unique biodistribution properties, in particular much less extraction by the liver, resulting in a higher delivery to other tissues, including tumor.

  9. Design, synthesis and in vitro anti-proliferative activity of 4,6-quinazolinediamines as potent EGFR-TK inhibitors.

    PubMed

    Mowafy, Samar; Farag, Nahla A; Abouzid, Khaled A M

    2013-03-01

    4-Anilino-6-substituted-quinazolines were designed, synthesized and evaluated for EGFR-TK and tumor growth inhibitory activities. The target compounds were designed with enamine ester or urea moieties appended at the C-6 of quinazoline as additional hydrogen bond acceptor functions. Most of the synthesized compounds displayed potent EGFR-TK inhibitory activity at 10 μM and the 6-ureido-anilinoquinazoline derivative 7a showed IC50 value of 0.061 μM. Moreover, six compounds were tested by National Cancer Institute (NCI), USA for their anti-proliferative activity at 10 μM in full NCI 60 cell panel. Compound 7a was further assayed for five dose molar ranges in full NCI 60 cell panel and exhibited remarkable growth inhibitory activity pattern against Non-Small Cell Lung Cancer EKVX (GI50 = 0.37 μM), NCI-H322M (GI50 = 0.36 μM), Renal Cancer A498 (GI50 = 0.46 μM), TK-10 (GI50 = 0.99 μM) and Breast Cancer MDA-MB-468 (GI50 = 1.096 μM) which are of high EGFR expression. Docking study was performed for the active compounds into ATP binding site of EGFR-TK which showed similar binding mode to gefitinib and additional binding with Cys-773 at the gatekeeper of EGFR-TK enzyme.

  10. Potent in vitro antiviral activity of Cistus incanus extract against HIV and Filoviruses targets viral envelope proteins

    PubMed Central

    Rebensburg, Stephanie; Helfer, Markus; Schneider, Martha; Koppensteiner, Herwig; Eberle, Josef; Schindler, Michael; Gürtler, Lutz; Brack-Werner, Ruth

    2016-01-01

    Novel therapeutic options are urgently needed to improve global treatment of virus infections. Herbal products with confirmed clinical safety features are attractive starting material for the identification of new antiviral activities. Here we demonstrate that Cistus incanus (Ci) herbal products inhibit human immunodeficiency virus (HIV) infections in vitro. Ci extract inhibited clinical HIV-1 and HIV-2 isolates, and, importantly, a virus isolate with multiple drug resistances, confirming broad anti-HIV activity. Antiviral activity was highly selective for virus particles, preventing primary attachment of the virus to the cell surface and viral envelope proteins from binding to heparin. Bioassay-guided fractionation indicated that Ci extract contains numerous antiviral compounds and therefore has favorably low propensity to induce virus resistance. Indeed, no resistant viruses emerged during 24 weeks of continuous propagation of the virus in the presence of Ci extracts. Finally, Ci extracts also inhibited infection by virus particles pseudotyped with Ebola and Marburg virus envelope proteins, indicating that antiviral activity of Ci extract extends to emerging viral pathogens. These results demonstrate that Ci extracts show potent and broad in vitro antiviral activity against viruses that cause life-threatening diseases in humans and are promising sources of agents that target virus particles. PMID:26833261

  11. Isolation and Characterization of an Endophytic Fungal Strain with Potent Antimicrobial and Termiticidal Activities From Port-Orford-Cedar.

    PubMed

    Sun, Liqing; Hse, Chung-Yun; Shupe, Todd; Sun, Mingjing; Wang, Xiaohua; Zhao, Kai

    2015-06-01

    Termites are responsible for an estimated US$1 billion annually in property damage, repairs, pest control, and prevention. There is an urgent need of finding a better alternative way to control and prevent termites. Port-Orford-Cedar (POC) has been known to have significant levels of natural durability and termiticidal activities due to its extractive contents. In this study, 25 endophytes including 22 fungal and 3 bacterial strains were isolated from the POC. Four strains, namely, HDZK-BYF21, HDZK-BYF1, HDZK-BYF2, and HDZK-BYB11, were chosen to test their termiticidal activities. The fermentation broth of strain HDZK-BYF21 displayed the potent antimicrobial and termiticidal activities. Morphological examination and 18 S rDNA sequence analysis demonstrated that strain HDZK-BYF21 belonged to the genus Aspergillus. This finding indicates the existence of an interesting chemical symbiosis between an endophytic fungus and its host. This is also the first report on endophytes isolated from the POC that may have potential termiticidal activities. Endophytes with termiticidal activities can be grown in bioreactor to provide an inexhaustible supply of bioactive compounds and thus can be exploited commercially.

  12. AZD-4547 exerts potent cytostatic and cytotoxic activities against fibroblast growth factor receptor (FGFR)-expressing colorectal cancer cells.

    PubMed

    Yao, Ting-Jing; Zhu, Jin-Hai; Peng, De-Feng; Cui, Zhen; Zhang, Chao; Lu, Pei-hua

    2015-07-01

    Colorectal cancer (CRC) causes significant mortalities worldwide. Fibroblast growth factor (FGF) receptor (FGFR) signaling is frequently dysregulated and/or constitutively activated in CRCs, contributing to cancer carcinogenesis and progression. Here, we studied the activity of AZD-4547, a novel and potent FGFR kinase inhibitor, on CRC cells. AZD-4547 inhibited CRC cell growth in vitro, and its activity correlated with the FGFR-1/2 expression level. AZD-4547 was cytotoxic and pro-apoptotic in FGFR-1/2-expressed CRC cell lines (NCI-H716 and HCT-116), but not in FGFR-1/2 null HT-29 cells. Further, AZD-4547 inhibited cell cycle progression and attenuated the activation of FGFR1-FGFR substrate 2 (FRS-2), ERK/mitogen-activated protein kinase (MAPK), and AKT/mammalian target of rapamycin (AKT/mTOR) signalings in NCI-H716 and HCT-116 cells. In vivo, AZD-4547 oral administration at effective doses inhibited NCI-H716 (high FGFR-1/2 expression) xenograft growth in nude mice. Phosphorylation of FGFR-1, AKT, and ERK1/2 in xenograft specimens was also inhibited by AZD-4547 administration. Thus, our preclinical studies strongly support possible clinical investigations of AZD-4547 for the treatment of CRCs harboring deregulated FGFR signalings. PMID:25691251

  13. Cytochrome P450-mediated activation of the fragrance compound geraniol forms potent contact allergens

    SciTech Connect

    Hagvall, Lina; Baron, Jens Malte; Boerje, Anna; Weidolf, Lars; Merk, Hans; Karlberg, Ann-Therese

    2008-12-01

    Contact sensitization is caused by low molecular weight compounds which penetrate the skin and bind to protein. In many cases, these compounds are activated to reactive species, either by autoxidation on exposure to air or by metabolic activation in the skin. Geraniol, a widely used fragrance chemical, is considered to be a weak allergen, although its chemical structure does not indicate it to be a contact sensitizer. We have shown that geraniol autoxidizes and forms allergenic oxidation products. In the literature, it is suggested but not shown that geraniol could be metabolically activated to geranial. Previously, a skin-like CYP cocktail consisting of cutaneous CYP isoenzymes, was developed as a model system to study cutaneous metabolism. In the present study, we used this system to investigate CYP-mediated activation of geraniol. In incubations with the skin-like CYP cocktail, geranial, neral, 2,3-epoxygeraniol, 6,7-epoxygeraniol and 6,7-epoxygeranial were identified. Geranial was the main metabolite formed followed by 6,7-epoxygeraniol. The allergenic activities of the identified metabolites were determined in the murine local lymph node assay (LLNA). Geranial, neral and 6,7-epoxygeraniol were shown to be moderate sensitizers, and 6,7-epoxygeranial a strong sensitizer. Of the isoenzymes studied, CYP2B6, CYP1A1 and CYP3A5 showed high activities. It is likely that CYP1A1 and CYP3A5 are mainly responsible for the metabolic activation of geraniol in the skin, as they are expressed constitutively at significantly higher levels than CYP2B6. Thus, geraniol is activated through both autoxidation and metabolism. The allergens geranial and neral are formed via both oxidation mechanisms, thereby playing a large role in the sensitization to geraniol.

  14. Cytochrome P450-mediated activation of the fragrance compound geraniol forms potent contact allergens.

    PubMed

    Hagvall, Lina; Baron, Jens Malte; Börje, Anna; Weidolf, Lars; Merk, Hans; Karlberg, Ann-Therese

    2008-12-01

    Contact sensitization is caused by low molecular weight compounds which penetrate the skin and bind to protein. In many cases, these compounds are activated to reactive species, either by autoxidation on exposure to air or by metabolic activation in the skin. Geraniol, a widely used fragrance chemical, is considered to be a weak allergen, although its chemical structure does not indicate it to be a contact sensitizer. We have shown that geraniol autoxidizes and forms allergenic oxidation products. In the literature, it is suggested but not shown that geraniol could be metabolically activated to geranial. Previously, a skin-like CYP cocktail consisting of cutaneous CYP isoenzymes, was developed as a model system to study cutaneous metabolism. In the present study, we used this system to investigate CYP-mediated activation of geraniol. In incubations with the skin-like CYP cocktail, geranial, neral, 2,3-epoxygeraniol, 6,7-epoxygeraniol and 6,7-epoxygeranial were identified. Geranial was the main metabolite formed followed by 6,7-epoxygeraniol. The allergenic activities of the identified metabolites were determined in the murine local lymph node assay (LLNA). Geranial, neral and 6,7-epoxygeraniol were shown to be moderate sensitizers, and 6,7-epoxygeranial a strong sensitizer. Of the isoenzymes studied, CYP2B6, CYP1A1 and CYP3A5 showed high activities. It is likely that CYP1A1 and CYP3A5 are mainly responsible for the metabolic activation of geraniol in the skin, as they are expressed constitutively at significantly higher levels than CYP2B6. Thus, geraniol is activated through both autoxidation and metabolism. The allergens geranial and neral are formed via both oxidation mechanisms, thereby playing a large role in the sensitization to geraniol.

  15. Activity of potent and selective host defense peptide mimetics in mouse models of oral candidiasis.

    PubMed

    Ryan, Lisa K; Freeman, Katie B; Masso-Silva, Jorge A; Falkovsky, Klaudia; Aloyouny, Ashwag; Markowitz, Kenneth; Hise, Amy G; Fatahzadeh, Mahnaz; Scott, Richard W; Diamond, Gill

    2014-07-01

    There is a strong need for new broadly active antifungal agents for the treatment of oral candidiasis that not only are active against many species of Candida, including drug-resistant strains, but also evade microbial countermeasures which may lead to resistance. Host defense peptides (HDPs) can provide a foundation for the development of such agents. Toward this end, we have developed fully synthetic, small-molecule, nonpeptide mimetics of the HDPs that improve safety and other pharmaceutical properties. Here we describe the identification of several HDP mimetics that are broadly active against C. albicans and other species of Candida, rapidly fungicidal, and active against yeast and hyphal cultures and that exhibit low cytotoxicity for mammalian cells. Importantly, specificity for Candida over commensal bacteria was also evident, thereby minimizing potential damage to the endogenous microbiome which otherwise could favor fungal overgrowth. Three compounds were tested as topical agents in two different mouse models of oral candidiasis and were found to be highly active. Following single-dose administrations, total Candida burdens in tongues of infected animals were reduced up to three logs. These studies highlight the potential of HDP mimetics as a new tool in the antifungal arsenal for the treatment of oral candidiasis.

  16. Activity of Potent and Selective Host Defense Peptide Mimetics in Mouse Models of Oral Candidiasis

    PubMed Central

    Ryan, Lisa K.; Freeman, Katie B.; Masso-Silva, Jorge A.; Falkovsky, Klaudia; Aloyouny, Ashwag; Markowitz, Kenneth; Hise, Amy G.; Fatahzadeh, Mahnaz; Scott, Richard W.

    2014-01-01

    There is a strong need for new broadly active antifungal agents for the treatment of oral candidiasis that not only are active against many species of Candida, including drug-resistant strains, but also evade microbial countermeasures which may lead to resistance. Host defense peptides (HDPs) can provide a foundation for the development of such agents. Toward this end, we have developed fully synthetic, small-molecule, nonpeptide mimetics of the HDPs that improve safety and other pharmaceutical properties. Here we describe the identification of several HDP mimetics that are broadly active against C. albicans and other species of Candida, rapidly fungicidal, and active against yeast and hyphal cultures and that exhibit low cytotoxicity for mammalian cells. Importantly, specificity for Candida over commensal bacteria was also evident, thereby minimizing potential damage to the endogenous microbiome which otherwise could favor fungal overgrowth. Three compounds were tested as topical agents in two different mouse models of oral candidiasis and were found to be highly active. Following single-dose administrations, total Candida burdens in tongues of infected animals were reduced up to three logs. These studies highlight the potential of HDP mimetics as a new tool in the antifungal arsenal for the treatment of oral candidiasis. PMID:24752272

  17. Structure-activity relationship for Fe(III)-salen-like complexes as potent anticancer agents.

    PubMed

    Ghanbari, Zahra; Housaindokht, Mohammad R; Izadyar, Mohammad; Bozorgmehr, Mohammad R; Eshtiagh-Hosseini, Hossein; Bahrami, Ahmad R; Matin, Maryam M; Khoshkholgh, Maliheh Javan

    2014-01-01

    Quantitative structure activity relationship (QSAR) for the anticancer activity of Fe(III)-salen and salen-like complexes was studied. The methods of density function theory (B3LYP/LANL2DZ) were used to optimize the structures. A pool of descriptors was calculated: 1497 theoretical descriptors and quantum-chemical parameters, shielding NMR, and electronic descriptors. The study of structure and activity relationship was performed with multiple linear regression (MLR) and artificial neural network (ANN). In nonlinear method, the adaptive neuro-fuzzy inference system (ANFIS) was applied in order to choose the most effective descriptors. The ANN-ANFIS model with high statistical significance (R (2) train = 0.99, RMSE = 0.138, and Q (2) LOO = 0.82) has better capability to predict the anticancer activity of the new compounds series of this family. Based on this study, anticancer activity of this compound is mainly dependent on the geometrical parameters, position, and the nature of the substituent of salen ligand. PMID:24955417

  18. Structure-Activity Relationship for Fe(III)-Salen-Like Complexes as Potent Anticancer Agents

    PubMed Central

    Ghanbari, Zahra; Housaindokht, Mohammad R.; Izadyar, Mohammad; Bozorgmehr, Mohammad R.; Eshtiagh-Hosseini, Hossein; Bahrami, Ahmad R.; Matin, Maryam M.; Khoshkholgh, Maliheh Javan

    2014-01-01

    Quantitative structure activity relationship (QSAR) for the anticancer activity of Fe(III)-salen and salen-like complexes was studied. The methods of density function theory (B3LYP/LANL2DZ) were used to optimize the structures. A pool of descriptors was calculated: 1497 theoretical descriptors and quantum-chemical parameters, shielding NMR, and electronic descriptors. The study of structure and activity relationship was performed with multiple linear regression (MLR) and artificial neural network (ANN). In nonlinear method, the adaptive neuro-fuzzy inference system (ANFIS) was applied in order to choose the most effective descriptors. The ANN-ANFIS model with high statistical significance (R2train = 0.99, RMSE = 0.138, and Q2LOO = 0.82) has better capability to predict the anticancer activity of the new compounds series of this family. Based on this study, anticancer activity of this compound is mainly dependent on the geometrical parameters, position, and the nature of the substituent of salen ligand. PMID:24955417

  19. Human Tyr-tRNA synthetase is a potent PARP-1 activating effector target for resveratrol

    PubMed Central

    Sajish, Mathew; Schimmel, Paul

    2014-01-01

    Resveratrol (RSV) is reported to extend life span1,2 and provide cardio-neuro-protective3, anti-diabetic4, and anti-cancer effects3,5 by initiating a stress response2 that induces survival genes. Because human tyrosyl tRNA synthetase (TyrRS) translocates to the nucleus under stress conditions6, we considered the possibility that the tyrosine-like phenolic ring of RSV might fit into the active site pocket to effect a nuclear role. Here we present a 2.1Å co-crystal structure of RSV bound to the active site of TyrRS. RSV nullified the catalytic activity and redirected TyrRS to a nuclear function, stimulating NAD+-dependent auto-poly-ADP-ribosylation of PARP-1. Downstream activation of key stress signaling pathways were causally connected to TyrRS-PARP-1-NAD+ collaboration. This collaboration was also demonstrated in the mouse, and was specifically blocked in vivo by a RSV-displacing tyrosyl adenylate analog. In contrast to functionally diverse tRNA synthetase catalytic nulls created by alternative splicing events that ablate active sites7, here a non-spliced TyrRS catalytic null reveals a new PARP-1- and NAD+-dependent dimension to the physiological mechanism of RSV. PMID:25533949

  20. Potent antibacterial activity of halogenated metabolites from Malaysian red algae, Laurencia majuscula (Rhodomelaceae, Ceramiales).

    PubMed

    Vairappan, Charles S

    2003-07-01

    Red algae genus Laurencia (Rhodomelaceae, Ceramiales) are known to produce a wide range of chemically interesting secondary halogenated metabolites. This investigation delves upon extraction, isolation, structural elucidation and antibacterial activity of inherently available secondary metabolites of Laurencia majuscula Harvey collected from two locations in waters of Sabah, Malaysia. Two major halogenated compounds, identified as elatol (1) and iso-obtusol (2) were isolated. Structures of these compounds were determined from their spectroscopic data such as IR, 1H-NMR, 13C-NMR and optical rotation. Antibacterial bioassay against human pathogenic bacteria was conducted using disc diffusion (Kirby-Bauer) method. Elatol (1) inhibited six species of bacteria, with significant antibacterial activities against Staphylococcus epidermis, Klebsiella pneumonia and Salmonella sp. while iso-obtusol (2) exhibited antibacterial activity against four bacterial species with significant activity against K. pneumonia and Salmonella sp. Elatol (1) showed equal and better antibacterial activity compared with tested commercial antibiotics while iso-obtusol (2) only equaled the potency of commercial antibiotics against K. pneumonia and Salmonella sp. Further tests conducted using dilution method showed both compounds as having bacteriostatic mode of action against the tested bacteria. PMID:12919806

  1. Omega-pyridiniumalkylethers of steroidal phenols: new compounds with potent antibacterial and antiproliferative activities.

    PubMed

    Lange, C; Holzhey, N; Schönecker, B; Beckert, R; Möllmann, U; Dahse, H-M

    2004-06-15

    Novel omega-pyridiniumalkylethers of two steroidal phenols were synthesized as compounds with potential antimicrobial activity. 3-Hydroxy-estra-1,3,5(10)-triene-17-one and 1-hydroxy-4-methyl-estra-1,3,5(10)-triene-17-one were reacted with omega,omega'-dibromoalkanes to omega-bromoalkoxy-estra-1,3,5(10)-trienes followed by reaction with pyridine to obtain the desired steroidal omega-pyridiniumalkoxy compounds as bromides. Their antimicrobial activity against strains of multiresistant Staphylococcus aureus (MRSA), a vancomycin resistant Enterococcus faecalis and fast growing mycobacteria depends clearly on the length of the alkyl chain. A strong broadband activity has been found for the compounds with eight or 10 C-atoms; in some cases better than ciprofloxacin or cetylpyridinium salts. In addition, the antiproliferative and cytotoxic activity depends on the chain length, too. The differentiation between antibacterial and cytotoxic activity is better for the steroid hybrid molecules than the cetylpyridinium salts. These new compounds can serve as lead compounds for further optimization.

  2. A Potent and Selective AMPK Activator That Inhibits de Novo Lipogenesis.

    PubMed

    Gómez-Galeno, Jorge E; Dang, Qun; Nguyen, Thanh H; Boyer, Serge H; Grote, Matthew P; Sun, Zhili; Chen, Mingwei; Craigo, William A; van Poelje, Paul D; MacKenna, Deidre A; Cable, Edward E; Rolzin, Paul A; Finn, Patricia D; Chi, Bert; Linemeyer, David L; Hecker, Scott J; Erion, Mark D

    2010-12-01

    AMP-activated protein kinase (AMPK) is a heterotrimeric kinase that regulates cellular energy metabolism by affecting energy-consuming pathways such as de novo lipid biosynthesis and glucose production as well as energy-producing pathways such as lipid oxidation and glucose uptake. Accordingly, compounds that activate AMPK represent potential drug candidates for the treatment of hyperlipidemia and type 2 diabetes. Screening of a proprietary library of AMP mimetics identified the phosphonic acid 2 that bears little structural resemblance to AMP but is capable of activating AMPK with high potency (EC50 = 6 nM vs AMP EC50 = 6 μM) and specificity. Phosphonate prodrugs of 2 inhibited de novo lipogenesis in cellular and animal models of hyperlipidemia.

  3. Discovery of novel N-substituted carbazoles as neuroprotective agents with potent anti-oxidative activity.

    PubMed

    Zhu, Daqian; Chen, Meihui; Li, Min; Luo, Bingling; Zhao, Yang; Huang, Peng; Xue, Fengtian; Rapposelli, Simona; Pi, Rongbiao; Wen, Shijun

    2013-10-01

    Carbazole moiety is an important scaffold with a variety of biological applications, for example, anti-oxidative stress. Our previous synthesized carbazoles were screened for their neuroprotective properties against two individual oxidative stresses. Some of the new carbazole derivatives were observed with modest to good neuroprotective effects on neuronal cells HT22 against cell injury induced by glutamate or homocysteic acid (HCA). Substituents introduced to the carbazole ring system play crucial roles in their biological activities. In particular, a bulky group favors the neuroprotective activity of the compounds. One of the new compounds, 6, showed the best neuroprotective effects, which might result from its anti-oxidative activity with a GSH-independent mechanism. These findings might provide an alternative strategy for the development of novel carbazole derivatives for the treatment of CNS diseases such as Alzheimer's disease.

  4. A Potent and Selective AMPK Activator That Inhibits de Novo Lipogenesis

    PubMed Central

    2010-01-01

    AMP-activated protein kinase (AMPK) is a heterotrimeric kinase that regulates cellular energy metabolism by affecting energy-consuming pathways such as de novo lipid biosynthesis and glucose production as well as energy-producing pathways such as lipid oxidation and glucose uptake. Accordingly, compounds that activate AMPK represent potential drug candidates for the treatment of hyperlipidemia and type 2 diabetes. Screening of a proprietary library of AMP mimetics identified the phosphonic acid 2 that bears little structural resemblance to AMP but is capable of activating AMPK with high potency (EC50 = 6 nM vs AMP EC50 = 6 μM) and specificity. Phosphonate prodrugs of 2 inhibited de novo lipogenesis in cellular and animal models of hyperlipidemia. PMID:24900234

  5. Optogenetic excitation of preBötzinger complex neurons potently drives inspiratory activity in vivo

    PubMed Central

    Alsahafi, Zaki; Dickson, Clayton T; Pagliardini, Silvia

    2015-01-01

    Understanding the sites and mechanisms underlying respiratory rhythmogenesis is of fundamental interest in the field of respiratory neurophysiology. Previous studies demonstrated the necessary and sufficient role of preBötzinger complex (preBötC) in generating inspiratory rhythms in vitro and in vivo. However, the influence of timed activation of the preBötC network in vivo is as yet unknown given the experimental approaches previously used. By unilaterally infecting preBötC neurons using an adeno-associated virus expressing channelrhodopsin we photo-activated the network in order to assess how excitation delivered in a spatially and temporally precise manner to the inspiratory oscillator influences ongoing breathing rhythms and related muscular activity in urethane-anaesthetized rats. We hypothesized that if an excitatory drive is necessary for rhythmogenesis and burst initiation, photo-activation of preBötC not only will increase respiratory rate, but also entrain it over a wide range of frequencies with fast onset, and have little effect on ongoing respiratory rhythm if a stimulus is delivered during inspiration. Stimulation of preBötC neurons consistently increased respiratory rate and entrained respiration up to fourfold baseline conditions. Furthermore, brief pulses of photostimulation delivered at random phases between inspiratory events robustly and consistently induced phase-independent (Type 0) respiratory reset and recruited inspiratory muscle activity at very short delays (∼100 ms). A 200 ms refractory period following inspiration was also identified. These data provide strong evidence for a fine control of inspiratory activity in the preBötC and provide further evidence that the preBötC network constitutes the fundamental oscillator of inspiratory rhythms. PMID:26010654

  6. Synthesis and pharmacological evaluation of a potent and selective σ1 receptor antagonist with high antiallodynic activity.

    PubMed

    Utech, Tina; Köhler, Jens; Buschmann, Helmut; Holenz, Jörg; Vela, Jose Miguel; Wünsch, Bernhard

    2011-07-01

    Based on the pharmacophore model of Glennon the conformationally restricted σ(1) receptor ligand 2 with a 1,3-dioxane moiety has been designed and synthesized. The three step synthesis (transacetalization with pentane-1,3,5-triol, tosylation, and nucleophilic substitution with benzylamine) provided diastereoselectively the cis-configured 1,3-dioxane 2 in good yields. The 1,3-dioxane 2 represents a potent σ(1) receptor ligand (K(i) = 19 nM) with moderate selectivity over the σ(2) subtype (K(i) = 92 nM) and excellent selectivity against more than 60 other targets. Additionally the hERG K(+) channel is not affected by 2. In the capsaicin assay 2 showed extraordinarily high analgesic activity with more than 70% analgesia at the very low dose of 0.25 mg/kg body weight, which indicates σ(1) antagonistic activity. Since 2 does only interact with σ(1) receptors, the in-vivo antiallodynic activity of 2 must be attributed to the σ(1) antagonistic activity. PMID:21598296

  7. Synthesis of a novel adamantyl nitroxide derivative with potent anti-hepatoma activity in vitro and in vivo

    PubMed Central

    Sun, Jin; Wang, Shan; Bu, Wei; Wei, Meng-Ying; Li, Wei-Wei; Yao, Min-Na; Ma, Zhong-Ying; Lu, Cheng-Tao; Li, Hui-Hui; Hu, Na-Ping; Zhang, En-Hu; Yang, Guo-Dong; Wen, Ai-Dong; Zhu, Xiao-He

    2016-01-01

    In this study, a novel adamantyl nitroxide derivative was synthesized and its antitumor activities in vitro and in vivo were investigated. The adamantyl nitroxide derivative 4 displayed a potent anticancer activity against all the tested human hepatoma cells, especially with IC50 of 68.1 μM in Bel-7404 cells, compared to the positive control 5-FU (IC50=607.7 μM). The significant inhibition of cell growth was also observed in xenograft mouse model, with low toxicity. Compound 4 suppressed the cell migration and invasion, induced the G2/M phase arrest. Further mechanistic studies revealed that compound 4 induced cell death, which was accompanied with damaging mitochondria, increasing the generation of intracellular reactive oxygen species, cleavages of caspase-9 and caspase-3, as well as activations of Bax and Bcl-2. These results confirmed that adamantyl nitroxide derivative exhibited selective antitumor activities via mitochondrial apoptosis pathway in Bel-7404 cells, and would be a potential anticancer agent for liver cancer. PMID:27429843

  8. Biological Clues to Potent DNA-Damaging Activities in Food and Flavoring

    PubMed Central

    Hossain, M. Zulfiquer; Gilbert, Samuel F.; Patel, Kalpesh; Ghosh, Soma; Bhunia, Anil K.; Kern, Scott E.

    2013-01-01

    Population differences in age-related diseases and cancer could stem from differences in diet. To characterize DNA strand-breaking activities in selected foods/beverages, flavorings, and some of their constituent chemicals, we used p53R cells, a cellular assay sensitive to such breaks. Substances testing positive included reference chemicals: quinacrine (peak response, 51X) and etoposide (33X); flavonoids: EGCG (19X), curcumin (12X), apigenin (9X), and quercetin (7X); beverages: chamomile (11X), green (21X), and black tea (26X) and coffee (3 to 29X); and liquid smoke (4 to 28X). Damage occurred at dietary concentrations: etoposide near 5 μg/ml produced responses similar to a 1:1000 dilution of liquid smoke, a 1:20 dilution of coffee, and a 1:5 dilution of tea. Pyrogallol-related chemicals and tannins are present in dietary sources and individually produced strong activity: pyrogallol (30X), 3-methoxycatechol (25X), gallic acid (21X), and 1,2,4-benzenetriol (21X). From structure-activity relationships, high activities depended on specific orientations of hydroxyls on the benzene ring. Responses accompanied cellular signals characteristic of DNA breaks such as H2AX phosphorylation. Breaks were also directly detected by comet assay. Cellular toxicological effects of foods and flavorings could guide epidemiologic and experimental studies of potential disease risks from DNA strand-breaking chemicals in diets. PMID:23402862

  9. Chemical constituents of Phragmanthera austroarabica A. G. Mill and J. A. Nyberg with potent antioxidant activity

    PubMed Central

    Badr, Jihan M.

    2015-01-01

    Background: Phragmanthera austroarabica A.G. Mill. and J. A. Nyberg is a semi parasitic plant belonging to family Loranthaceae. It was collected from Saudi Arabia. It is widely used in folk medicine among the kingdom in treatment of various diseases including diabetes mellitus. Objective: The total alcoholic extract of P. austroarabica collected from Saudi Arabia was investigated for the chemical structure and prominent biological activity of the main constituents. Materials and Methods: Isolation of the active constituents was performed using different chromatographic techniques including column chromatography packed with silica or sephadex and preparative thin layer chromatography. The structures of the isolated compounds were established based on different spectroscopic data as mass spectrum, one-dimensional and two-dimensional nuclear magnetic resonance (correlation spectroscopy, heteronuclear single quantum coherence, and heteronuclear multiple-bond correlation). Results: Phytochemical investigation of the plant resulted in isolation of 12 compounds. The isolated compounds were identified as chrysophanic acid, emodin, chrysophanic acid-8-O-glucoside, emodin-8-O-glucoside, pectolinarigenin, quercetin, dillenetin-3-O-glucoside, catechin, catechin-4’-O-gallate, methyl gallate, lupeol and ursolic acid. All the isolated phenolic compounds revealed significant free radical scavenging activities when tested using 2,2-diphenyl-1-picrylhydrazyl reagent. Conclusion: The antioxidant activities of the isolated compounds can justify the use of P. austroarabica in traditional medicine for treatment of diabetes and verify its possible application as an antihyperglycemic drug. PMID:26692747

  10. Potent chemopreventive/antioxidant activity detected in common spices of the Apiaceae family

    PubMed Central

    Jeyabalan, Jeyaprakash; Aqil, Farrukh; Soper, Lisa; Schultz, David J.; Gupta, Ramesh C.

    2015-01-01

    Spices are used worldwide, particularly, in the Asian and Middle-Eastern countries and considered protective against degenerative diseases, including cancer. Here, we report the efficacy of aqueous and non-aqueous extracts of eleven Apiaceae spices for free radical-scavenging activity and to inhibit cytochrome P450s in two separate reactions involving: i) 4-hydroxy-17β-estradiol (4E2), DNA and CuCl2 and ii) 17β-estradiol, rat liver microsomes, co-factors, DNA and CuCl2. Oxidative DNA adducts resulting from redox cycling of 4E2 were analyzed by 32P-postlabeling. Aqueous (5 mg/ml) and non-aqueous extracts (6 mg/ml) substantially inhibited (83% – 98%) formation of DNA adducts in the microsomal reaction. However, in non-microsomal reaction, only aqueous extracts showed the inhibitory activity (83% – 96%). Adduct inhibition was also observed at 5-fold lower concentrations of aqueous extracts of cumin (60%) and caraway (90%), and 10-fold lower concentrations of carrot seeds (76%) and ajowan (90%). These results suggests the presence of two groups of phytochemicals - polar compounds that have free radical-scavenging activity, and lipophilic compounds that selectively inhibit P450 activity associated with estrogen metabolism. Because most of these Apiaceae spices are used widely with no known toxicity, the phytochemicals from the Apiaceae spices used in foods may be potentially protective against estrogen-mediated breast cancer. PMID:26381237

  11. Potent Chemopreventive/Antioxidant Activity Detected in Common Spices of the Apiaceae Family.

    PubMed

    Jeyabalan, Jeyaprakash; Aqil, Farrukh; Soper, Lisa; Schultz, David J; Gupta, Ramesh C

    2015-01-01

    Spices are used worldwide, particularly in the Asian and Middle Eastern countries, and considered protective against degenerative diseases, including cancer. Here, we report the efficacy of aqueous and non-aqueous extracts of 11 Apiaceae spices for free radical-scavenging activity and to inhibit cytochrome P450s in two separate reactions involving: 1) 4-hydroxy-17ß-estradiol (4E2), DNA, and CuCl2 and 2) 17ß-estradiol, rat liver microsomes, cofactors, DNA and CuCl2. Oxidative DNA adducts resulting from redox cycling of 4E2 were analyzed by (32)P-postlabeling. Aqueous (5 mg/ml) and non-aqueous extracts (6 mg/ml) substantially inhibited (83-98%) formation of DNA adducts in the microsomal reaction. However, in nonmicrosomal reaction, only aqueous extracts showed the inhibitory activity (83-96%). Adduct inhibition was also observed at five-fold lower concentrations of aqueous extracts of cumin (60%) and caraway (90%), and 10-fold lower concentrations of carrot seeds (76%) and ajowan (90%). These results suggests the presence of 2 groups of phytochemicals: polar compounds that have free radical-scavenging activity and lipophilic compounds that selectively inhibit P450 activity associated with estrogen metabolism. Because most of these Apiaceae spices are used widely with no known toxicity, the phytochemicals from the Apiaceae spices used in foods may be potentially protective against estrogen-mediated breast cancer.

  12. Potent Chemopreventive/Antioxidant Activity Detected in Common Spices of the Apiaceae Family.

    PubMed

    Jeyabalan, Jeyaprakash; Aqil, Farrukh; Soper, Lisa; Schultz, David J; Gupta, Ramesh C

    2015-01-01

    Spices are used worldwide, particularly in the Asian and Middle Eastern countries, and considered protective against degenerative diseases, including cancer. Here, we report the efficacy of aqueous and non-aqueous extracts of 11 Apiaceae spices for free radical-scavenging activity and to inhibit cytochrome P450s in two separate reactions involving: 1) 4-hydroxy-17ß-estradiol (4E2), DNA, and CuCl2 and 2) 17ß-estradiol, rat liver microsomes, cofactors, DNA and CuCl2. Oxidative DNA adducts resulting from redox cycling of 4E2 were analyzed by (32)P-postlabeling. Aqueous (5 mg/ml) and non-aqueous extracts (6 mg/ml) substantially inhibited (83-98%) formation of DNA adducts in the microsomal reaction. However, in nonmicrosomal reaction, only aqueous extracts showed the inhibitory activity (83-96%). Adduct inhibition was also observed at five-fold lower concentrations of aqueous extracts of cumin (60%) and caraway (90%), and 10-fold lower concentrations of carrot seeds (76%) and ajowan (90%). These results suggests the presence of 2 groups of phytochemicals: polar compounds that have free radical-scavenging activity and lipophilic compounds that selectively inhibit P450 activity associated with estrogen metabolism. Because most of these Apiaceae spices are used widely with no known toxicity, the phytochemicals from the Apiaceae spices used in foods may be potentially protective against estrogen-mediated breast cancer. PMID:26381237

  13. Broad and potent antiviral activity of the NAE inhibitor MLN4924

    PubMed Central

    Le-Trilling, Vu Thuy Khanh; Megger, Dominik A.; Katschinski, Benjamin; Landsberg, Christine D.; Rückborn, Meike U.; Tao, Sha; Krawczyk, Adalbert; Bayer, Wibke; Drexler, Ingo; Tenbusch, Matthias; Sitek, Barbara; Trilling, Mirko

    2016-01-01

    In terms of infected human individuals, herpesviruses range among the most successful virus families. Subclinical herpesviral infections in healthy individuals contrast with life-threatening syndromes under immunocompromising and immunoimmature conditions. Based on our finding that cytomegaloviruses interact with Cullin Roc ubiquitin ligases (CRLs) in the context of interferon antagonism, we systematically assessed viral dependency on CRLs by utilizing the drug MLN4924. CRL activity is regulated through the conjugation of Cullins with the ubiquitin-like molecule Nedd8. By inhibiting the Nedd8-activating Enzyme (NAE), MLN4924 interferes with Nedd8 conjugation and CRL activity. MLN4924 exhibited pronounced antiviral activity against mouse and human cytomegalovirus, herpes simplex virus (HSV)- 1 (including multi-drug resistant clinical isolates), HSV-2, adeno and influenza viruses. Human cytomegalovirus genome amplification was blocked at nanomolar MLN4924 concentrations. Global proteome analyses revealed that MLN4924 blocks cytomegaloviral replication despite increased IE1 amounts. Expression of dominant negative Cullins assigned this IE regulation to defined Cullin molecules and phenocopied the antiviral effect of MLN4924. PMID:26829401

  14. Negatively charged liposomes show potent adjuvant activity when simply admixed with protein antigens

    PubMed Central

    Yanasarn, Nijaporn; Sloat, Brian R.; Cui, Zhengrong

    2011-01-01

    Liposomes have been investigated extensively as a vaccine delivery system. Herein the adjuvant activities of liposomes with different net surface charges (neutral, positive, or negative) were evaluated when admixed with protein antigens, ovalbumin (OVA, pI = 4.7), Bacillus anthracis protective antigen protein (PA, pI = 5.6), or cationized OVA (cOVA). Mice immunized subcutaneously with OVA admixed with different liposomes generated different antibody responses. Interestingly, OVA admixed with net negatively charged liposomes prepared with DOPA was as immunogenic as OVA admixed with positively charged liposomes prepared with DOTAP. Immunization of mice with the anthrax PA protein admixed with the net negatively charged DOPA liposomes also induced a strong and functional anti-PA antibody response. When the cationized OVA was used as a model antigen, liposomes with net neutral, negative, or positive charges showed comparable adjuvant activities. Immunization of mice with the OVA admixed with DOPA liposomes also induced OVA-specific CD8+ cytotoxic T lymphocyte responses and significantly delayed the growth of OVA-expressing B16-OVA tumors in mice. However, not all net negatively charged liposomes showed a strong adjuvant activity. The adjuvant activity of the negatively charged liposomes may be related to the liposome’s ability (i) to up-regulate the expression of molecules related to the activation and maturation of antigen-presenting cells and (ii) to slightly facilitate the uptake of the antigens by antigen-presenting cells. Simply admixing certain negatively charged liposomes with certain protein antigens of interest may represent a novel platform for vaccine development. PMID:21615153

  15. Oncostatin M secreted by skin infiltrating T lymphocytes is a potent keratinocyte activator involved in skin inflammation.

    PubMed

    Boniface, Katia; Diveu, Caroline; Morel, Franck; Pedretti, Nathalie; Froger, Josy; Ravon, Elisa; Garcia, Martine; Venereau, Emilie; Preisser, Laurence; Guignouard, Emmanuel; Guillet, Gérard; Dagregorio, Guy; Pène, Jérôme; Moles, Jean-Pierre; Yssel, Hans; Chevalier, Sylvie; Bernard, François-Xavier; Gascan, Hugues; Lecron, Jean-Claude

    2007-04-01

    Cutaneous inflammatory diseases such as psoriasis vulgaris and atopic dermatitis are associated with altered keratinocyte function, as well as with a particular cytokine production profile of skin-infiltrating T lymphocytes. In this study we show that normal human epidermal keratinocytes express a functional type II oncostatin-M (OSM) receptor (OSMR) consisting of the gp130 and OSMRbeta components, but not the type I OSMR. The type II OSMR is expressed in skin lesions from both psoriatic patients and those with atopic dermatitis. Its ligand, OSM, induces via the recruitment of the STAT3 and MAP kinase pathways a gene expression profile in primary keratinocytes and in a reconstituted epidermis that is characteristic of proinflammatory and innate immune responses. Moreover, OSM is a potent stimulator of keratinocyte migration in vitro and increases the thickness of a reconstituted epidermis. OSM transcripts are enhanced in both psoriatic and atopic dermatitic skin as compared with healthy skin and mirror the enhanced production of OSM by T cells isolated from diseased lesions. Results from a microarray analysis comparing the gene-modulating effects of OSM with those of 33 different cytokines indicate that OSM is a potent keratinocyte activator similar to TNF-alpha, IL-1, IL-17, and IL-22 and that it acts in synergy with the latter cytokines in the induction of S100A7 and beta-defensin 2 expression, characteristic of psoriatic skin. Taken together, these results demonstrate that OSM and its receptor play an important role in cutaneous inflammatory responses in general and that the specific effects of OSM are associated with distinct inflammatory diseases depending on the cytokine environment.

  16. Synthesis and characterization of tritylthioethanamine derivatives with potent KSP inhibitory activity.

    PubMed

    Rodriguez, Delany; Ramesh, Chinnasamy; Henson, Lauren H; Wilmeth, Lori; Bryant, Bj K; Kadavakollu, Samuel; Hirsch, Rebecca; Montoya, Johnelle; Howell, Porsha R; George, Jon M; Alexander, David; Johnson, Dennis L; Arterburn, Jeffrey B; Shuster, Charles B

    2011-09-15

    Assembly of a bipolar mitotic spindle requires the action of class 5 kinesins, and inhibition or depletion of this motor results in mitotic arrest and apoptosis. S-Trityl-l-cysteine is an allosteric inhibitor of vertebrate Kinesin Spindle Protein (KSP) that has generated considerable interest due to its anti-cancer properties, however, poor pharmacological properties have limited the use of this compound. We have modified the triphenylmethyl and cysteine groups, guided by biochemical and cell-based assays, to yield new cysteinol and cysteamine derivatives with increased inhibitory activity, greater efficacy in model systems, and significantly enhanced potency against the NCI60 tumor panel. These results reveal a promising new class of conformationally-flexible small molecules as allosteric KSP inhibitors for use as research tools, with activities that provide impetus for further development as anti-tumor agents.

  17. The antimicrobial peptide pardaxin exerts potent anti-tumor activity against canine perianal gland adenoma

    PubMed Central

    Pan, Chieh-Yu; Lin, Chao-Nan; Chiou, Ming-Tang; Yu, Chao Yuan; Chen, Jyh-Yih; Chien, Chi-Hsien

    2015-01-01

    Pardaxin is an antimicrobial peptide of 33 amino acids, originally isolated from marine fish. We previously demonstrated that pardaxin has anti-tumor activity against murine fibrosarcoma, both in vitro and in vivo. In this study, we examined the anti-tumor activity, toxicity profile, and maximally-tolerated dose of pardaxin treatment in dogs with different types of refractory tumor. Local injection of pardaxin resulted in a significant reduction of perianal gland adenoma growth between 28 and 38 days post-treatment. Surgical resection of canine histiocytomas revealed large areas of ulceration, suggesting that pardaxin acts like a lytic peptide. Pardaxin treatment was not associated with significant variations in blood biochemical parameters or secretion of immune-related proteins. Our findings indicate that pardaxin has strong therapeutic potential for treating perianal gland adenomas in dogs. These data justify the veterinary application of pardaxin, and also provide invaluable information for veterinary medicine and future human clinical trials. PMID:25544775

  18. Characterization of the potent in vitro and in vivo antimalarial activities of ionophore compounds.

    PubMed Central

    Gumila, C; Ancelin, M L; Delort, A M; Jeminet, G; Vial, H J

    1997-01-01

    Large-scale in vitro screening of different types of ionophores previously pinpointed nine compounds that were very active and selective in vitro against Plasmodium falciparum; their in vitro and in vivo antimalarial effects were further studied. Addition of the ionophores to synchronized P. falciparum suspensions revealed that all P. falciparum stages were sensitive to the drugs. However, the schizont stages were three- to ninefold more sensitive, and 12 h was required for complete parasite clearance. Pretreatment of healthy erythrocytes with toxic doses of ionophores for 24 to 48 h showed that the activity was not due to an irreversible effect on the host erythrocyte. No preferential ionophore adsorption in infected or uninfected erythrocytes occurred. On the other hand, ionophore molecules strongly bound to serum proteins since increasing the serum concentration from 2 to 50% led to almost a 25-fold parallel increase in the ionophore 50% inhibitory concentration. Mice infected with the malaria parasites Plasmodium vinckei petteri or Plasmodium chabaudi were successfully treated with eight ionophores in a 4-day suppressive test. The 50% effective dose after intraperitoneal administration ranged from 0.4 to 4.1 mg/kg of body weight, and the therapeutic indices were about 5 for all ionophores except monensin A methyl ether, 5-bromo lasalocid A, and gramicidin D, whose therapeutic indices were 12, 18, and 344, respectively. These three compounds were found to be curative, with no recrudescence. Gramicidin D, which presented impressive antimalarial activity, requires parenteral administration, while 5-bromo lasalocid A has the major advantage of being active after oral administration. Overall, the acceptable levels of toxicity and the good in vivo therapeutic indices in the rodent model highlight the interesting potential of these ionophores for the treatment of malaria in higher animals. PMID:9055986

  19. Structural basis of binding and rationale for the potent urease inhibitory activity of biscoumarins.

    PubMed

    Lodhi, Muhammad Arif; Shams, Sulaiman; Choudhary, Muhammad Iqbal; Lodhi, Atif; Ul-Haq, Zaheer; Jalil, Saima; Nawaz, Sarfraz Ahmad; Khan, Khalid Mohammed; Iqbal, Sajid; Rahman, Atta-ur

    2014-01-01

    Urease belongs to a family of highly conserved urea-hydrolyzing enzymes. A common feature of these enzymes is the presence of two Lewis acid nickel ions and reactive cysteine residue in the active sites. In the current study we examined a series of biscoumarins 1-10 for their mechanisms of inhibition with the nickel containing active sites of Jack bean and Bacillus pasteurii ureases. All these compounds competitively inhibited Jack bean urease through interaction with the nickel metallocentre, as deduced from Michaelis-Menten kinetics, UV-visible absorbance spectroscopic, and molecular docking simulation studies. Some of the compounds behaved differently in case of Bacillus pasteurii urease. We conducted the enzyme kinetics, UV-visible spectroscopy, and molecular docking results in terms of the known protein structure of the enzyme. We also evaluated possible molecular interpretations for the site of biscoumarins binding and found that phenyl ring is the major active pharmacophore. The excellent in vitro potency and selectivity profile of the several compounds described combined with their nontoxicity against the human cells and plants suggest that these compounds may represent a viable lead series for the treatment of urease associated problems. PMID:25295281

  20. Are pharmaceuticals potent environmental pollutants? Part I: environmental risk assessments of selected active pharmaceutical ingredients.

    PubMed

    Carlsson, Carina; Johansson, Anna-Karin; Alvan, Gunnar; Bergman, Kerstin; Kühler, Thomas

    2006-07-01

    As part of achieving national environmental goals, the Swedish Government commissioned an official report from the Swedish Medical Products Agency on environmental effects of pharmaceuticals. Considering half-lives/biodegradability, environmental occurrence, and Swedish sales statistics, 27 active pharmaceutical ingredients were selected for environmental hazard and risk assessments. Although there were large data gaps for many of the compounds, nine ingredients were identified as dangerous for the aquatic environment. Only the sex hormones oestradiol and ethinyloestradiol were considered to be associated with possible aquatic environmental risks. We conclude that risk for acute toxic effects in the environment with the current use of active pharmaceutical ingredients is unlikely. Chronic environmental toxic effects, however, cannot be excluded due to lack of chronic ecotoxicity data. Measures to reduce potential environmental impact posed by pharmaceutical products must be based on knowledge on chronic ecotoxic effects of both active pharmaceutical ingredients as well as excipients. We believe that the impact pharmaceuticals have on the environment should be further studied and be given greater attention such that informed assessments of hazards as well as risks can be done. PMID:16257037

  1. Potent Activities of Roemerine against Candida albicans and the Underlying Mechanisms.

    PubMed

    Ma, Chaoyu; Du, Faya; Yan, Lan; He, Gonghao; He, Jianchang; Wang, Chengying; Rao, Gaoxiong; Jiang, Yuanying; Xu, Guili

    2015-01-01

    Roemerine (RM) is an aporphine alkaloid isolated from the fresh rattan stem of Fibraurea recisa, and it has been demonstrated to have certain antifungal activity. This study aimed to investigate the antifungal activity of RM and the underlying mechanisms in Candida albicans (C. albicans). The in vitro antifungal activity of RM was evaluated by a series of experiments, including the XTT reduction assay, confocal laser scanning microscopy assay, scanning electron microscope assay. Results showed that 1 μg/mL RM inhibited biofilm formation significantly (p < 0.01) both in Spider medium and Lee's medium. In addition, RM could inhibit yeast-to-hyphae transition of C. albicans in a dose-dependent manner. The biofilm-specific and hypha-specific genes such as YWP1, SAP5, SAP6, HWP1, ECE1 were up-regulated and EFG1 was down-regulated after 8 μg/mL RM treatment. Furthermore, the toxicity of RM was investigated using C. elegans worms, three cancer cells and one normal cell. The date showed that RM had no significant toxicity. In conclusion, RM could inhibited the formation of C. albicans biofilm in vitro, but it had no fungicidal effect on planktonic C. albicans cells, and the anti-biofilm mechanism may be related to the cAMP pathway.

  2. Structure-activity relationship of highly potent galactonoamidine inhibitors toward β-galactosidase (Aspergillus oryzae).

    PubMed

    Fan, Qiu-Hua; Claunch, Kailey A; Striegler, Susanne

    2014-11-13

    A small library of 22 N-substituted galactonoamidines was synthesized, and their structure-activity relationship for inhibition of the hydrolytic activity of β-galactosidase (Aspergillus oryzae) was evaluated. A fast screening assay in 96-well plate format was used to follow the enzymatic hydrolysis of 2-chloro-4-nitrophenyl-β-D-galactopyranoside using UV-vis spectroscopy. The aglycon moiety of all compounds was found to have a profound effect on their inhibitory ability. In general, galactonoamidines derived from cyclic aliphatic and linear amines show higher inhibition activity than those derived from benzylamines. Hydrophobic interactions of the methyl group rather than π-π stacking interactions of the aromatic ring in p-methylbenzyl-D-galactonoamidine were identified to cause its transition-state-like character and the remarkably high inhibitory ability (K(i) = 8 nM). A flexible 3-carbon methylene spacer between the exo N atom of the sugar moiety and a phenyl group furthermore increased the observed apparent inhibition drastically.

  3. Structural Basis of Binding and Rationale for the Potent Urease Inhibitory Activity of Biscoumarins

    PubMed Central

    Lodhi, Muhammad Arif; Choudhary, Muhammad Iqbal; Lodhi, Atif; Ul-Haq, Zaheer; Jalil, Saima; Nawaz, Sarfraz Ahmad; Khan, Khalid Mohammed; Iqbal, Sajid; Rahman, Atta-ur

    2014-01-01

    Urease belongs to a family of highly conserved urea-hydrolyzing enzymes. A common feature of these enzymes is the presence of two Lewis acid nickel ions and reactive cysteine residue in the active sites. In the current study we examined a series of biscoumarins 1–10 for their mechanisms of inhibition with the nickel containing active sites of Jack bean and Bacillus pasteurii ureases. All these compounds competitively inhibited Jack bean urease through interaction with the nickel metallocentre, as deduced from Michaelis-Menten kinetics, UV-visible absorbance spectroscopic, and molecular docking simulation studies. Some of the compounds behaved differently in case of Bacillus pasteurii urease. We conducted the enzyme kinetics, UV-visible spectroscopy, and molecular docking results in terms of the known protein structure of the enzyme. We also evaluated possible molecular interpretations for the site of biscoumarins binding and found that phenyl ring is the major active pharmacophore. The excellent in vitro potency and selectivity profile of the several compounds described combined with their nontoxicity against the human cells and plants suggest that these compounds may represent a viable lead series for the treatment of urease associated problems. PMID:25295281

  4. Potent Activities of Roemerine against Candida albicans and the Underlying Mechanisms.

    PubMed

    Ma, Chaoyu; Du, Faya; Yan, Lan; He, Gonghao; He, Jianchang; Wang, Chengying; Rao, Gaoxiong; Jiang, Yuanying; Xu, Guili

    2015-01-01

    Roemerine (RM) is an aporphine alkaloid isolated from the fresh rattan stem of Fibraurea recisa, and it has been demonstrated to have certain antifungal activity. This study aimed to investigate the antifungal activity of RM and the underlying mechanisms in Candida albicans (C. albicans). The in vitro antifungal activity of RM was evaluated by a series of experiments, including the XTT reduction assay, confocal laser scanning microscopy assay, scanning electron microscope assay. Results showed that 1 μg/mL RM inhibited biofilm formation significantly (p < 0.01) both in Spider medium and Lee's medium. In addition, RM could inhibit yeast-to-hyphae transition of C. albicans in a dose-dependent manner. The biofilm-specific and hypha-specific genes such as YWP1, SAP5, SAP6, HWP1, ECE1 were up-regulated and EFG1 was down-regulated after 8 μg/mL RM treatment. Furthermore, the toxicity of RM was investigated using C. elegans worms, three cancer cells and one normal cell. The date showed that RM had no significant toxicity. In conclusion, RM could inhibited the formation of C. albicans biofilm in vitro, but it had no fungicidal effect on planktonic C. albicans cells, and the anti-biofilm mechanism may be related to the cAMP pathway. PMID:26426004

  5. In vitro properties of designed antimicrobial peptides that exhibit potent antipneumococcal activity and produces synergism in combination with penicillin

    PubMed Central

    Le, Cheng-Foh; Yusof, Mohd Yasim Mohd; Hassan, Hamimah; Sekaran, Shamala Devi

    2015-01-01

    Antimicrobial peptides (AMPs) represent a promising class of novel antimicrobial agents owing to their potent antimicrobial activity. In this study, two lead peptides from unrelated classes of AMPs were systematically hybridized into a series of five hybrid peptides (DM1- DM5) with conserved N- and C-termini. This approach allows sequence bridging of two highly dissimilar AMPs and enables sequence-activity relationship be detailed down to single amino acid level. Presence of specific amino acids and physicochemical properties were used to describe the antipneumococcal activity of these hybrids. Results obtained suggested that cell wall and/or membrane targeting could be the principal mechanism exerted by the hybrids leading to microbial cell killing. Moreover, the pneumocidal rate was greater than penicillin (PEN). Combination treatment with both DMs and PEN produced synergism. The hybrids were also broad spectrum against multiple common clinical bacteria. Sequence analysis showed that presence of specific residues has a major role in affecting the antimicrobial and cell toxicity of the hybrids than physicochemical properties. Future studies should continue to investigate the mechanisms of actions, in vivo therapeutic potential, and improve rational peptide design based on the current strategy. PMID:25985150

  6. Synthesis and potent antitumor activity of new arylamino derivatives of nor-beta-lapachone and nor-alpha-lapachone.

    PubMed

    da Silva Júnior, Eufrânio N; de Souza, Maria Cecília B V; Pinto, Antônio V; Pinto, Maria do Carmo F R; Goulart, Marilia O F; Barros, Francisco W A; Pessoa, Claudia; Costa-Lotufo, Letícia V; Montenegro, Raquel C; de Moraes, Manoel O; Ferreira, Vitor F

    2007-11-15

    Several arylamino derivatives of nor-beta-lapachone were synthesized in moderate to high yields and found to show very potent cytotoxicity against six neoplastic cancer cells: SF-295 (central nervous system), HCT-8 (colon), MDAMB-435 (breast), HL-60 (leukaemia), PC-3 (prostate), and B-16 (murine melanoma), with IC(50) below 1 microg/mL. Their cytotoxicities were compared to doxorubicin and with their synthetic precursors, beta-lapachone and nor-beta-lapachone. The activity against a normal murine fibroblast L-929 showed that some of the compounds were selective against cancer cells. The absence of hemolytic activity (EC(50)>200 microg/mL), performed with erythrocyte suspensions, suggests that the cytotoxicity of the compounds was not related to membrane damage of mouse erythrocytes. For comparison purposes, one isomeric compound based on nor-alpha-lapachone was also synthesized and showed lower activity than the related ortho-derivative. The modified arylamino quinones appear as interesting new lead compounds in anti-cancer drug development.

  7. One novel quinoxaline derivative as a potent human cyclophilin A inhibitor shows highly inhibitory activity against mouse spleen cell proliferation.

    PubMed

    Li, Jian; Chen, Jing; Zhang, Li; Wang, Feng; Gui, Chunshan; Zhang, Li; Qin, Yu; Xu, Qiang; Liu, Hong; Nan, Fajun; Shen, Jingkang; Bai, Donglu; Chen, Kaixian; Shen, Xu; Jiang, Hualiang

    2006-08-15

    Cyclophilin A (CypA) is a ubiquitous cellular enzyme playing critical roles in many biological processes, and its inhibitor has been reported to have potential immunosuppressive activity. In this work, we reported a novel quinoxaline derivative, 2,3-di(furan-2-yl)-6-(3-N,N-diethylcarbamoyl-piperidino)carbonylamino quinoxaline (DC838, 3), which was confirmed to be a potent inhibitor against human CypA. By using the surface plasmon resonance (SPR) and fluorescence titration techniques, the kinetic analysis of CypA/DC838 interaction was quantitatively performed. CypA peptidyl prolyl cis-trans isomerase (PPIase) activity inhibition assay showed that DC838 demonstrated highly CypA PPIase inhibitory activity. In vivo assay results showed that DC838 could inhibit mouse spleen cell proliferation induced by concanavalin A (Con A). Molecular docking simulation further elucidated the specific DC838 binding to CypA at the atomic level. The current work should provide useful information in the discovery of immunosuppressor based on CypA inhibitor.

  8. Discovery of novel heteroarylmethylcarbamodithioates as potent anticancer agents: Synthesis, structure-activity relationship analysis and biological evaluation.

    PubMed

    Li, Ying-Bo; Yan, Xu; Li, Ri-Dong; Liu, Peng; Sun, Shao-Qian; Wang, Xin; Cui, Jing-Rong; Zhou, De-Min; Ge, Ze-Mei; Li, Run-Tao

    2016-04-13

    A series of new analogs based on the structure of lead compound 10 were designed, synthesized and evaluated for their in vitro anti-cancer activities against four selected human cancer cell lines (HL-60, Bel-7402, SK-BR-3 and MDA-MB-468). Several synthesized compounds exhibited improved anti-cancer activities comparing with lead compound 10. Among them, 1,3,4-oxadiazole analogs 17o showed highest bioactivity with IC50 values of 1.23, 0.58 and 4.29 μM against Bel-7402, SK-BR-3 and MDA-MB-468 cells, respectively. It is noteworthy that 17o has potent anti-proliferation activity toward a panel of cancer cells with relatively less cytotoxicity to nonmalignant cells. The further mechanistic study showed that it induced apoptosis and cell cycle arrest through disrupting spindle assembly in mitotic progression, indicating these synthesized dithiocarbamates represented a novel series of anti-cancer compounds targeting mitosis. PMID:26900655

  9. Novel STAT3 phosphorylation inhibitors exhibit potent growth suppressive activity in pancreatic and breast cancer cells

    PubMed Central

    Lin, Li; Hutzen, Brian; Zuo, Mingxin; Ball, Sarah; Deangelis, Stephanie; Foust, Elizabeth; Pandit, Bulbul; Ihnat, Michael A.; Shenoy, Satyendra S.; Kulp, Samuel; Li, Pui-Kai; Li, Chenglong; Fuchs, James; Lin, Jiayuh

    2010-01-01

    The constitutive activation of Signal Transducer and Activator of Transcription 3 (STAT3) is frequently detected in most types of human cancer where it plays important roles in survival, drug-resistance, angiogenesis, and other functions. Targeting constitutive STAT3 signaling is thus an attractive therapeutic approach for these cancers. We have recently developed novel small molecule STAT3 inhibitors known as FLLL31 and FLLL32, which are derived from curcumin (the primary bioactive compound of turmeric). These compounds are designed to bind selectively to Janus Kinase 2 (JAK2) and the STAT3 SH2 domain, which serves crucial roles in STAT3 dimerization and signal transduction. Here we show that FLLL31 and FLLL32 are effective inhibitors of STAT3 phosphorylation, DNA binding activity, and transactivation in vitro, leading to the impediment of multiple oncogenic processes and the induction of apoptosis in pancreatic and breast cancer cell lines. FLLL31 and FLLL32 also inhibit colony formation in soft agar, cell invasion, and exhibit synergy with the anti-cancer drug doxorubicin against breast cancer cells. In addition, we show that FLLL32 can inhibit the induction of STAT3 phosphorylation by Interferon-α (IFNα) and Interleukin-6 (IL-6) in breast cancer cells. We also demonstrate that administration of FLLL32 can inhibit tumor growth and vascularity in chicken embryo xenografts as well as substantially reduce tumor volumes in mouse xenografts. Our findings highlight the potential of these new compounds and their efficacy in targeting pancreatic and breast cancers that exhibit constitutive STAT3 signaling. PMID:20215512

  10. Potent Antidiabetic Activity and Metabolite Profiling of Melicope Lunu-ankenda Leaves.

    PubMed

    Al-Zuaidy, Mizher Hezam; Hamid, Azizah Abdul; Ismail, Amin; Mohamed, Suhaila; Abdul Razis, Ahmad Faizal; Mumtaz, Muhammad Waseem; Salleh, Syafiq Zikri

    2016-05-01

    Diabetes mellitus is normally characterized by chronic hyperglycemia associated with disturbances in the fat, carbohydrate, and protein metabolism. There is an increasing trend of using natural products instead of synthetic agents as alternative therapy for disorders due to their fewer side effects. In this study, antidiabetic and antioxidant activities of different Melicope lunu-ankenda (ML) ethanolic extracts were evaluated using inhibition of α-glucosidase and 2,2-diphenyl-l-picrylhydrazyl (DPPH) radicals scavenging activity, respectively; whereas, proton nuclear magnetic resonance ((1) H NMR) and ultra-high performance liquid chromatography-tandem mass spectrometric (UHPLC-MS/MS) techniques were used for metabolite profiling of ML leaf extracts at different concentrations of ethanol and water. Sixty percent of ethanolic ML extract showed highest inhibitory effect against α-glucosidase enzyme (IC50 of 37 μg/mL) and DPPH scavenging activity (IC50 of 48 μg/mL). Antidiabetic effect of ML extracts was also evaluated in vivo and it was found that the high doses (400 mg/Kg BW) of ML extract exhibited high suppression in fasting blood glucose level by 62.75%. The metabolites responsible for variation among ML samples with variable ethanolic levels have been evaluated successfully using (1) H-NMR-based metabolomics. The principal component analysis (PCA) and partial least squares(PLS) analysis scores depicted clear and distinct separations into 4 clusters representing the 4 ethanolic concentrations by PC1 and PC2, with an eigenvalue of 69.9%. Various (1) H-NMR chemical shifts related to the metabolites responsible for sample difference were also ascribed. The main bioactive compounds identified attributing toward the separation included: isorhamnetin, skimmianine, scopoletin, and melicarpinone. Hence, ML may be used as promising medicinal plant for the development of new functional foods, new generation antidiabetic drugs, as a single entity phytomedicine or in

  11. Potent Antidiabetic Activity and Metabolite Profiling of Melicope Lunu-ankenda Leaves.

    PubMed

    Al-Zuaidy, Mizher Hezam; Hamid, Azizah Abdul; Ismail, Amin; Mohamed, Suhaila; Abdul Razis, Ahmad Faizal; Mumtaz, Muhammad Waseem; Salleh, Syafiq Zikri

    2016-05-01

    Diabetes mellitus is normally characterized by chronic hyperglycemia associated with disturbances in the fat, carbohydrate, and protein metabolism. There is an increasing trend of using natural products instead of synthetic agents as alternative therapy for disorders due to their fewer side effects. In this study, antidiabetic and antioxidant activities of different Melicope lunu-ankenda (ML) ethanolic extracts were evaluated using inhibition of α-glucosidase and 2,2-diphenyl-l-picrylhydrazyl (DPPH) radicals scavenging activity, respectively; whereas, proton nuclear magnetic resonance ((1) H NMR) and ultra-high performance liquid chromatography-tandem mass spectrometric (UHPLC-MS/MS) techniques were used for metabolite profiling of ML leaf extracts at different concentrations of ethanol and water. Sixty percent of ethanolic ML extract showed highest inhibitory effect against α-glucosidase enzyme (IC50 of 37 μg/mL) and DPPH scavenging activity (IC50 of 48 μg/mL). Antidiabetic effect of ML extracts was also evaluated in vivo and it was found that the high doses (400 mg/Kg BW) of ML extract exhibited high suppression in fasting blood glucose level by 62.75%. The metabolites responsible for variation among ML samples with variable ethanolic levels have been evaluated successfully using (1) H-NMR-based metabolomics. The principal component analysis (PCA) and partial least squares(PLS) analysis scores depicted clear and distinct separations into 4 clusters representing the 4 ethanolic concentrations by PC1 and PC2, with an eigenvalue of 69.9%. Various (1) H-NMR chemical shifts related to the metabolites responsible for sample difference were also ascribed. The main bioactive compounds identified attributing toward the separation included: isorhamnetin, skimmianine, scopoletin, and melicarpinone. Hence, ML may be used as promising medicinal plant for the development of new functional foods, new generation antidiabetic drugs, as a single entity phytomedicine or in

  12. Potent Anti-Inflammatory Activity of Tetramethylpyrazine Is Mediated through Suppression of NF-k

    PubMed Central

    Chen, Wei; Chen, Weixiong; Zhu, Jinshui; Chen, Niwei; Lu, Yunmin

    2016-01-01

    The purpose of the current study was to evaluate the anti-inflammatory activity of tetramethlpyrazine on oxazolone-induced colitis mice. Spleen mononuclear cells (SMC), lamina propria mononuclear cells (LPMC) and peripheral blood mononuclear cells (PBMC) were isolated from oxazolone-induced colitis and normal mice. The colitis cells treated by oxazolone were randomly divided into model, low dose, middle dose and high dose groups treated with 0, 0.5, 1.0 and 2.0 g/L tetramethlpyrazine, respectively. The apoptotic rate of SMC and LPMC in the oxazolone-induced group was lower than that in the normal group. Compared with model group, apoptotic rate of SMC was significantly increased in the high dose group, while the apoptotic rate of LPMC in the middle dose group was increased. Compared with SMC, LPMC and PBMC of normal group, the mRNA level of nuclear factor kappa B (NF-kB), transcription factor-activated protein-1 (AP-1) and nuclear factor of activated T cells (NF-AT) were higher in model group. Tetramethylpyrazine inhibited the increase of NF-kB, AP-1 and NF-AT mRNA induced by oxazolone. For SMC, LPMC and PBMC there was significant difference in the mRNA level of AP-1 among the three different doses of tetramethylpyrazine treated groups. However, no significant difference was observed in the mRNA levels of NF-AT and NF-κB between normal and middle groups. Tetramethylpyrazine promoted the apoptotic rate of SMC and LPMC in-vitro, and suppressed the expression of transcription factors in SMC, LPMC and PBMC isolated from oxazolone-induced colitis mice. The study provides a novel insight into the mechanism behind the effect of etramethylpyrazine on colitis. PMID:27610159

  13. A New Octadecenoic Acid Derivative from Caesalpinia gilliesii Flowers with Potent Hepatoprotective Activity

    PubMed Central

    Osman, Samir M.; El-Haddad, Alaadin E.; El-Raey, Mohamed A.; Abd El-Khalik, Soad M.; Koheil, Mahmoud A.; Wink, Michael

    2016-01-01

    Background: Caesalpinia gilliesii Hook is an ornamental shrub with showy yellow flowers. It was used in folk medicine due to its contents of different classes of secondary metabolites. In our previous study, dichloromethane extract of C. gilliesii flowers showed a good antioxidant activity. Aim of the Study: Isolation and identification of bioactive hepatoprotective compounds from C. gilliesii flowers dichloromethane fraction. Materials and Methods: The hepatoprotective activity of dichloromethane fraction and isolated compounds were studied in CCl4-intoxicated rat liver slices by measuring liver injury markers (alanine aminotransferase, aspartate aminotransferase and glutathione [GSH]). All compounds were structurally elucidated on the basis of electron ionization-mass spectrometry, one- and two-dimensional nuclear magnetic resonance. Results: A new 12,13,16-trihydroxy-14(Z)-octadecenoic acid was identified in addition to the known β-sitosterol-3-O-butyl, daucosterol, isorhamnetin, isorhamnetin-3-O-rhamnoside, luteolin-7,4’-dimethyl ether, genistein-5-methyl ether, luteolin-7-O-rhamnoside, isovanillic acid, and p-methoxybenzoic acid. Dichloromethane fraction and isorhamnetin were able to significantly protect the liver against intoxication. Moreover, the dichloromethane fraction and the isolated phytosterols induced GSH above the normal level. Conclusion: The hepatoprotective activity of C. gilliesii may be attributed to its high content of phytosterols and phenolic compounds. SUMMARY Bioactive Hepatoprotective phytosterols and phenolics from chloroform extract of Caesalpinia gilliesii Abbreviations used: ALT: Alanine Aminotransferase; AST: Aspartate aminotransferase; GSH: Glutathione; SC50: Scavenging Capacity 50 (SC 50); COSY: Correlation spectroscopy; NMR: Nuclear Magnetic Resonance; CC: Column chromatography; EI-MS: Electron-impact mass spectrometry; HSQC: Heteronuclear single-quantum correlation. PMID:27563221

  14. Potent Anti-Inflammatory Activity of Tetramethylpyrazine Is Mediated through Suppression of NF-k.

    PubMed

    Chen, Wei; Chen, Weixiong; Zhu, Jinshui; Chen, Niwei; Lu, Yunmin

    2016-01-01

    The purpose of the current study was to evaluate the anti-inflammatory activity of tetramethlpyrazine on oxazolone-induced colitis mice. Spleen mononuclear cells (SMC), lamina propria mononuclear cells (LPMC) and peripheral blood mononuclear cells (PBMC) were isolated from oxazolone-induced colitis and normal mice. The colitis cells treated by oxazolone were randomly divided into model, low dose, middle dose and high dose groups treated with 0, 0.5, 1.0 and 2.0 g/L tetramethlpyrazine, respectively. The apoptotic rate of SMC and LPMC in the oxazolone-induced group was lower than that in the normal group. Compared with model group, apoptotic rate of SMC was significantly increased in the high dose group, while the apoptotic rate of LPMC in the middle dose group was increased. Compared with SMC, LPMC and PBMC of normal group, the mRNA level of nuclear factor kappa B (NF-kB), transcription factor-activated protein-1 (AP-1) and nuclear factor of activated T cells (NF-AT) were higher in model group. Tetramethylpyrazine inhibited the increase of NF-kB, AP-1 and NF-AT mRNA induced by oxazolone. For SMC, LPMC and PBMC there was significant difference in the mRNA level of AP-1 among the three different doses of tetramethylpyrazine treated groups. However, no significant difference was observed in the mRNA levels of NF-AT and NF-κB between normal and middle groups. Tetramethylpyrazine promoted the apoptotic rate of SMC and LPMC in-vitro, and suppressed the expression of transcription factors in SMC, LPMC and PBMC isolated from oxazolone-induced colitis mice. The study provides a novel insight into the mechanism behind the effect of etramethylpyrazine on colitis. PMID:27610159

  15. Potent antiprotozoal activity of a novel semi-synthetic berberine derivative.

    PubMed

    Bahar, Mark; Deng, Ye; Zhu, Xiaohua; He, Shanshan; Pandharkar, Trupti; Drew, Mark E; Navarro-Vázquez, Armando; Anklin, Clemens; Gil, Roberto R; Doskotch, Raymond W; Werbovetz, Karl A; Kinghorn, A Douglas

    2011-05-01

    Treatment of diseases such as African sleeping sickness and leishmaniasis often depends on relatively expensive or toxic drugs, and resistance to current chemotherapeutics is an issue in treating these diseases and malaria. In this study, a new semi-synthetic berberine analogue, 5,6-didehydro-8,8-diethyl-13-oxodihydroberberine chloride (1), showed nanomolar level potency against in vitro models of leishmaniasis, malaria, and trypanosomiasis as well as activity in an in vivo visceral leishmaniasis model. Since the synthetic starting material, berberine hemisulfate, is inexpensive, 8,8-dialkyl-substituted analogues of berberine may lead to a new class of affordable antiprotozoal compounds.

  16. Highly Potent, Water Soluble Benzimidazole Antagonist for Activated (alpha)4(beta)1 Integrin

    SciTech Connect

    Carpenter, R D; Andrei, M; Lau, E Y; Lightstone, F C; Liu, R; Lam, K S; Kurth, M J

    2007-08-29

    The cell surface receptor {alpha}{sub 4}{beta}{sub 1} integrin, activated constitutively in lymphoma, can be targeted with the bisaryl urea peptidomimetic antagonist 1 (LLP2A). However, concerns on its preliminary pharmacokinetic (PK) profile provided an impetus to change the pharmacophore from a bisaryl urea to a 2-arylaminobenzimidazole moiety resulting in improved solubility while maintaining picomolar potency [5 (KLCA4); IC{sub 50} = 305 pM]. With exceptional solubility, this finding has potential for improving PK to help diagnose and treat lymphomas.

  17. Synthesis and biological activity of trans-tiliroside derivatives as potent anti-diabetic agents.

    PubMed

    Zhu, Yujin; Zhang, Yanjun; Liu, Yi; Chu, Hongwan; Duan, Hongquan

    2010-12-10

    A set of novel trans-tiliroside derivatives were synthesized. The structures of the derivatives were identified by their IR, 1H-NMR, and MS spectra analysis. Their anti-diabetic activities were evaluated on the insulin resistant (IR) HepG2 cell model. As a result, compounds 7a, 7c, 7h, and trans-tiliroside exhibited significant glucose consumption-enhancing effects in IR-HepG2 cells compared with the positive control (metformin). This research provides useful clues for further design and discovery of anti-diabetic agents.

  18. Synthesis, Docking and Biological Activities of Novel Hybrids Celecoxib and Anthraquinone Analogs as Potent Cytotoxic Agents

    PubMed Central

    Almutairi, Maha S.; Hegazy, Gehan H.; Haiba, Mogedda E.; Ali, Hamed I.; Khalifa, Nagy M.; Soliman, Abd El-mohsen M.

    2014-01-01

    Herein, novel hybrid compounds of celecoxib and 2-aminoanthraquinone derivatives have been synthesized using condensation reactions of celecoxib with 2-aminoanthraquinone derivatives or 2-aminoanthraquinon with celecoxib derivatives. Celecoxib was reacted with different acid chlorides, 2-chloroethylisocyanate and bis (2-chloroethyl) amine hydrochloride. These intermediates were then reacted with 2-aminoanthraquinone. Also the same different acid chlorides and 2-chloroethylisocyanate were reacted with 2-aminoanthraquinone and the resulting intermediates were reacted with celecoxib to give isomers for the previous compounds. The antitumor activities against hepatic carcinoma tumor cell line (HEPG2) have been investigated in vitro, and all these compounds showed promising activities, especially compound 3c, 7, and 12. Flexible docking studies involving AutoDock 4.2 was investigated to identify the potential binding affinities and the mode of interaction of the hybrid compounds into two protein tyrosine kinases namely, SRC (Pp60v-src) and platelet-derived growth factor receptor, PDGFR (c-Kit). The compounds in this study have a preferential affinity for the c-Kit PDGFR PTK over the non-receptor tyrosine kinase SRC (Pp60v-src). PMID:25490139

  19. Novel composite plastics containing silver(I) acylpyrazolonato additives display potent antimicrobial activity by contact.

    PubMed

    Marchetti, Fabio; Palmucci, Jessica; Pettinari, Claudio; Pettinari, Riccardo; Condello, Francesca; Ferraro, Stefano; Marangoni, Mirko; Crispini, Alessandra; Scuri, Stefania; Grappasonni, Iolanda; Cocchioni, Mario; Nabissi, Massimo; Chierotti, Michele R; Gobetto, Roberto

    2015-01-01

    New silver(I) acylpyrazolonato derivatives displaying a mononuclear, polynuclear, or ionic nature, as a function of the ancillary azole ligands used in the synthesis, have been fully characterized by thermal analysis, solution NMR spectroscopy, solid-state IR and NMR spectroscopies, and X-ray diffraction techniques. These derivatives have been embedded in polyethylene (PE) matrix, and the antimicrobial activity of the composite materials has been tested against three bacterial strains (E. coli, P. aeruginosa, and S. aureus): Most of the composites show antimicrobial action comparable to PE embedded with AgNO3 . Tests by contact and release tests for specific migration of silver from PE composites clearly indicate that, at least in the case of the PE, for composites containing polynuclear silver(I) additives, the antimicrobial action is exerted by contact, without release of silver ions. Moreover, PE composites can be re-used several times, displaying the same antimicrobial activity. Membrane permeabilization studies and induced reactive oxygen species (ROS) generation tests confirm the disorganization of bacterial cell membranes. The cytotoxic effect, evaluated in CD34(+) cells by MTT (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazoliumbromide) and CFU (colony forming units) assays, indicates that the PE composites do not induce cytotoxicity in human cells. Studies of ecotoxicity, based on the test of Daphnia magna, confirm tolerability of the PE composites by higher organisms and exclude the release of Ag(+) ions in sufficient amounts to affect water environment.

  20. Dithiocarbamates with potent inhibitory activity against the Saccharomyces cerevisiae β-carbonic anhydrase.

    PubMed

    Bozdag, Murat; Carta, Fabrizio; Vullo, Daniela; Isik, Semra; AlOthman, Zeid; Osman, Sameh M; Scozzafava, Andrea; Supuran, Claudiu T

    2016-01-01

    Dithiocarbamates (DTCs) prepared from primary or secondary amines, which incorporated amino/hydroxyl-alkyl, mono-/bicyclic aliphatic/heterocyclic rings based on the quinuclidine, piperidine, hydroxy-/carboxy-/amino-substituted piperidine, morpholine and piperazine scaffolds, were investigated for the inhibition of α- and β-carbonic anhydrases (CAs, EC 4.2.1.1) of pharmacologic relevance, such as the human (h) isoform hCA I and II, as well as the Saccharomyces cerevisiae β-CA, scCA. The yeast and its β-CA were shown earlier to be useful models of pathogenic fungal infections. The DTCs investigated here were medium potency hCA I inhibitors (K(I)s of 66.5-910 nM), were more effective as hCA II inhibitors (K(I)s of 8.9-107 nM) and some of them showed excellent, low nanomolar activity against the yeast enzyme, with inhibition constants ranging between 6.4 and 259 nM. The detailed structure activity relationship for inhibition of the yeast and human enzymes is discussed. Several of the investigated DTCs showed excellent selectivity ratios for inhibiting the yeast over the human cytosolic CA isoforms. PMID:25669351

  1. Potent and Selective Monoamine Oxidase-B Inhibitory Activity: Fluoro- vs. Trifluoromethyl-4-hydroxylated Chalcone Derivatives.

    PubMed

    Mathew, Bijo; Mathew, Githa Elizabeth; Uçar, Gülberk; Baysal, Ipek; Suresh, Jerad; Mathew, Sincy; Haridas, Abitha; Jayaprakash, Venkatesan

    2016-08-01

    For various neurodegenerative disorders like Alzheimer's and Parkinson's diseases, selective and reversible MAO-B inhibitors have a great therapeutic value. In our previous study, we have shown that a series of methoxylated chalcones with F functional group exhibited high binding affinity toward human monoamine oxidase-B (hMAO-B). In continuation of our earlier study and to extend the understanding of the structure-activity relationships, a series of five new chalcones were studied for their inhibition of hMAO. The results demonstrated that these compounds are reversible and selective hMAO-B inhibitors with a competitive mode of inhibition. The most active compound, (2E)-1-(4-hydroxyphenyl)-3-[4-(trifluoromethyl)phenyl]prop-2-en-1-one, exhibited a Ki value of 0.33 ± 0.01 μm toward hMAO-B with a selectivity index of 26.36. A molecular docking study revealed that the presence of a H-bond network in hydroxylated chalcone with the N(5) atom of FAD is crucial for MAO-B selectivity and potency.

  2. Characterization of new human CD20 monoclonal antibodies with potent cytolytic activity against non-Hodgkin lymphomas.

    PubMed

    Teeling, Jessica L; French, Ruth R; Cragg, Mark S; van den Brakel, Jeroen; Pluyter, Marielle; Huang, Haichun; Chan, Claude; Parren, Paul W H I; Hack, C Erik; Dechant, Michael; Valerius, Thomas; van de Winkel, Jan G J; Glennie, Martin J

    2004-09-15

    Despite the rapid and widespread integration of chimeric CD20 monoclonal antibody (mAb), rituximab, into the management of non-Hodgkin lymphoma, its efficacy remains variable and often modest when used as a single agent. To develop more potent reagents, human immunoglobulin transgenic mice were used to generate a panel of immunoglobulin G1kappa (IgG1kappa) CD20 mAbs. All reagents bound strongly to CD20(+) cells and recruited mononuclear cells for the lysis of malignant B cells. However, 2 mAbs, 2F2 and 7D8, were exceptionally active in complement-dependent cytotoxicity (CDC), being able to lyse a range of rituximab-resistant targets, such as CD20-low chronic lymphocytic leukemia (CLL), in the presence of human plasma or unfractionated blood. Further analysis showed that 2F2 and 7D8, like rituximab, redistributed CD20 into Triton X-100-insoluble regions of the plasma membrane, but that they had markedly slower off-rates. To determine whether off-rate influenced CDC, a non-complement activating F(ab')(2) antihuman kappa reagent was used. This reagent markedly slowed the off-rate of rituximab and increased its CDC activity to that of 2F2 and 7D8. Thus, with increasing evidence that mAb therapeutic activity in vivo depends on complement activation, these new CD20 reagents with their slow off-rates and increased potency in CDC hold considerable promise for improved clinical activity.

  3. Anti-HIV-1 Activity of Elafin Is More Potent than Its Precursor's, Trappin-2, in Genital Epithelial Cells

    PubMed Central

    Drannik, Anna G.; Nag, Kakon; Yao, Xiao-Dan; Henrick, Bethany M.; Jain, Sumiti; Ball, T. Blake; Plummer, Francis A.; Wachihi, Charles; Kimani, Joshua

    2012-01-01

    Cervicovaginal lavage fluid (CVL) is a natural source of anti-HIV-1 factors; however, molecular characterization of the anti-HIV-1 activity of CVL remains elusive. In this study, we confirmed that CVLs from HIV-1-resistant (HIV-R) compared to HIV-1-susceptible (HIV-S) commercial sex workers (CSWs) contain significantly larger amounts of serine antiprotease trappin-2 (Tr) and its processed form, elafin (E). We assessed anti-HIV-1 activity of CVLs of CSWs and recombinant E and Tr on genital epithelial cells (ECs) that possess (TZM-bl) or lack (HEC-1A) canonical HIV-1 receptors. Our results showed that immunodepletion of 30% of Tr/E from CVL accounted for up to 60% of total anti-HIV-1 activity of CVL. Knockdown of endogenous Tr/E in HEC-1A cells resulted in significantly increased shedding of infectious R5 and X4 HIV-1. Pretreatment of R5, but not X4 HIV-1, with either Tr or E led to inhibition of HIV-1 infection of TZM-bl cells. Interestingly, when either HIV-1 or cells lacking canonical HIV-1 receptors were pretreated with Tr or E, HIV-1 attachment and transcytosis were significantly reduced, and decreased attachment was not associated with altered expression of syndecan-1 or CXCR4. Determination of 50% inhibitory concentrations (IC50) of Tr and E anti-HIV-1 activity indicated that E is ∼130 times more potent than its precursor, Tr, despite their equipotent antiprotease activities. This study provides the first experimental evidence that (i) Tr and E are among the principal anti-HIV-1 molecules of CVL; (ii) Tr and E affect cell attachment and transcytosis of HIV-1; (iii) E is more efficient than Tr regarding anti-HIV-1 activity; and (iv) the anti-HIV-1 effect of Tr and E is contextual. PMID:22345469

  4. Honey, pollen, and propolis extracts show potent inhibitory activity against the zinc metalloenzyme carbonic anhydrase.

    PubMed

    Sahin, H; Aliyazicioglu, R; Yildiz, O; Kolayli, S; Innocenti, A; Supuran, C T

    2011-06-01

    Three different honey extracts from the endemic plant in the Black Sea region Rhododendron ponticum, were investigated for their inhibitory effects against the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1), more precisely the human (h) isoforms hCA I and hCA II. Hexane, methanol, ethanol, and water solid-phase extractions (SPEs) showed inhibitory activity towards the two CA isozymes which were related to the total phenolic content. The highest inhibitory effects (0.036-0.039 mg/mL) were those of propolis methanolic extract. Among the three different samples investigated here, the aqueous extracts showed lower inhibitory effects compared to the organic solvent SPE extracts (in the range of 1.150- 5.144 mg/mL). The studied honey extracts constitute an interesting source of phenolic derivatives that might serve to identify lead compounds, targeting the physiologically relevant enzymes CA I and CA II.

  5. Development of GoSlo-SR-5-69, a potent activator of large conductance Ca2+-activated K+ (BK) channels.

    PubMed

    Roy, Subhrangsu; Large, Roddy J; Akande, Adebola Morayo; Kshatri, Aravind; Webb, Tim I; Domene, Carmen; Sergeant, Gerard P; McHale, Noel G; Thornbury, Keith D; Hollywood, Mark A

    2014-03-21

    We have designed, synthesised and characterised the effects of a number of novel anthraquinone derivatives and assessed their effects on large conductance, Ca(2+) activated K(+) (BK) channels recorded from rabbit bladder smooth muscle cells using the excised, inside/out configuration of the patch clamp technique. These compounds are members of the GoSlo-SR family of compounds, which potently open BK channels and shift the voltage required for half maximal activation (V1/2) negatively. The efficacy of the anilinoanthraquinone derivatives was enhanced when the size of ring D was increased, since the cyclopentane and cyclohexane derivatives shifted the V1/2, by -24 ± 6 mV and -54 ± 8 mV, respectively, whereas the cycloheptane and cyclooctane derivatives shifted the V1/2 by -61 ± 6 mV and -106 ± 6 mV. To examine if a combination of hydrophobicity and steric bulking of this region further enhanced their ability to open BK channels, we synthesised a number of naphthalene and tetrahydro-naphthalene derivatives. The tetrahydro-2-naphthalene derivative GoSlo-SR-5-69 was the most potent and efficacious of the series since it was able to shift the activation V1/2 by greater than -100 mV when applied at a concentration of 1 μM and had an EC50 of 251 nM, making it one of the most potent and efficacious BK channel openers synthesised to date. PMID:24561672

  6. Design and synthesis of chalcone derivatives as potent tyrosinase inhibitors and their structural activity relationship

    NASA Astrophysics Data System (ADS)

    Akhtar, Muhammad Nadeem; Sakeh, Nurshafika M.; Zareen, Seema; Gul, Sana; Lo, Kong Mun; Ul-Haq, Zaheer; Shah, Syed Adnan Ali; Ahmad, Syahida

    2015-04-01

    Browning of fruits and vegetables is a serious issue in the food industry, as it damages the organoleptic properties of the final products. Overproduction of melanin causes aesthetic problems such as melisma, freckles and lentigo. In this study, a series of chalcones (1-10) have been synthesized and examined for their tryrosinase inhibitory activity. The results showed that flavokawain B (1), flavokawain A (2) and compound 3 were found to be potential tyrosinase inhibitors, indicating IC50 14.20-14.38 μM values. This demonstrates that 4-substituted phenolic compound especially at ring A exhibited significant tyrosinase inhibition. Additionally, molecular docking results showed a strong binding affinity for compounds 1-3 through chelation between copper metal and ligands. The detailed molecular docking and SARs studies correlate well with the tyrosinase inhibition studies in vitro. The structures of these compounds were elucidated by the 1D and 2D NMR spectroscopy, mass spectrometry and single X-ray crystallographic techniques. These findings could lead to design and discover of new tyrosinase inhibitors to control the melanine overproduction and overcome the economic loss of food industry.

  7. Actinomycin D binding mode reveals the basis for its potent HIV-1 and cancer activity

    NASA Astrophysics Data System (ADS)

    Paramanathan, Thayaparan; Vladescu, Ioana D.; McCauley, Micah J.; Rouzina, Ioulia; Williams, Mark C.

    2011-03-01

    Actinomycin D (ActD) is one of the most studied antibiotics, which has been used as an anti-cancer agent and also shown to inhibit HIV reverse transcription. Initial studies with ActD established that it intercalates double stranded DNA (dsDNA). However, recent studies have shown that ActD binds with even higher affinity to single stranded DNA (ssDNA). In our studies we use optical tweezers to stretch and hold single dsDNA molecule at constant force in the presence of varying ActD concentrations until the binding reaches equilibrium. The change in dsDNA length upon ActD binding measured as a function of time yields the rate of binding in addition to the equilibrium lengthening of DNA. The results suggest extremely slow kinetics, on the order of several minutes and 0.52 +/- 0.06 μ M binding affinity. Holding DNA at constant force while stretching and relaxing suggests that ActD binds to two single strands that are close to each other rather than to pure dsDNA or ssDNA. This suggests that biological activity of ActD that contributes towards the inhibition of cellular replication is due to its ability to bind at DNA bubbles during RNA transcription, thereby stalling the transcription process.

  8. Potent antimicrobial activity of bone cement encapsulating silver nanoparticles capped with oleic acid

    PubMed Central

    Prokopovich, Polina; Köbrick, Mathias; Brousseau, Emmanuel; Perni, Stefano

    2015-01-01

    Bone cement is widely used in surgical treatments for the fixation for orthopaedic devices. Subsequently, 2–3% of patients undergoing these procedures develop infections that are both a major health risk for patients and a cost for the health service providers; this is also aggravated by the fact that antibiotics are losing efficacy because of the rising resistance of microorganisms to these substances. In this study, oleic acid capped silver nanoparticles (NP) were encapsulated into Poly(methyl methacrylate) (PMMA)-based bone cement samples at various ratios. Antimicrobial activity against Methicillin Resistant Staphylococcus aureus, S. aureus, Staphylococcus epidermidis, Acinetobacter baumannii was exhibited at NP concentrations as low as 0.05% (w/w). Furthermore, the mechanical properties and cytotoxicity of the bone cement containing these NP were assessed to guarantee that such material is safe to be used in orthopaedic surgical practice. © 2014 The Authors. Journal of Biomedical Materials Research Part B: Applied Biomaterials Published by Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 273–281, 2015. PMID:24819471

  9. Tocotrienol-Rich Fraction from Rice Bran Demonstrates Potent Radiation Protection Activity.

    PubMed

    Krager, Kimberly J; Pineda, E Nathalie; Kharade, Sujay V; Kordsmeier, Mary; Howard, Luke; Breen, Philip J; Compadre, Cesar M; Hauer-Jensen, Martin; Aykin-Burns, Nukhet

    2015-01-01

    The vitamin E analogs δ-tocotrienol (DT3) and γ-tocotrienol (GT3) have significant protective and mitigative capacity against the detrimental effects of ionizing radiation (IR). However, the expense of purification limits their potential use. This study examined the tocotrienol-rich fraction of rice bran (TRFRB) isolated from rice bran deodorizer distillate, a rice oil refinement waste product, to determine its protective effects against IR induced oxidative damage and H2O2. Several cell lines were treated with tocotrienols or TRFRB prior to or following exposure to H2O2 or IR. To determine the radioprotective capacity cells were analyzed for morphology, mitochondrial bioenergetics, clonogenic survival, glutathione oxidation, cell cycle, and migration rate. TRFRB displayed similar antioxidant activity compared to pure tocotrienols. Cells pretreated with TRFRB or DT3 exhibited preserved cell morphology and mitochondrial respiration when exposed to H2O2. Oxidized glutathione was decreased in TRFRB treated cells exposed to IR. TRFRB reversed mitochondrial uncoupling and protected cells migration rates following IR exposure. The protective antioxidant capacity of TRFRB treated cells against oxidative injury was similar to that of purified DT3. TRFRB effectively protects normal cells against IR induced injury suggesting that rice bran distillate may be an inexpensive and abundant alternate source. PMID:26425129

  10. Licochalcone A, a novel antiparasitic agent with potent activity against human pathogenic protozoan species of Leishmania.

    PubMed Central

    Chen, M; Christensen, S B; Blom, J; Lemmich, E; Nadelmann, L; Fich, K; Theander, T G; Kharazmi, A

    1993-01-01

    Licochalcone A, an oxygenated chalcone isolated from the roots of Chinese licorice plant, inhibited the growth of both Leishmania major and Leishmania donovani promastigotes and amastigotes. The structure of the licochalcone A was established by mass and nuclear magnetic resonance spectroscopies and by synthesis, and its purity was verified by high-pressure liquid chromatography. The 50% inhibition of growth of logarithmic- and stationary-phase promastigotes of L. major, as measured by [3H]thymidine uptake, were 4 and 2.5 micrograms/ml, respectively. The growth of L. major promastigotes was totally inhibited after a 20-h incubation period with licochalcone A at 5 micrograms/ml. At a concentration of 0.5 microgram/ml, licochalcone A markedly reduced the infection rate of human peripheral blood monocyte-derived macrophages and U937 cells with L. major promastigotes and exhibited a strong intracellular killing of the parasite. These data show that intracellular Leishmania amastigotes are more susceptible than promastigotes to licochalcone A. Results of studies on the site of action of licochalcone A indicate that the target organelle appears to be the parasite mitochondria. These findings demonstrate that licochalcone A in concentrations that are nontoxic to host cells exhibits a strong antileishmanial activity and that appropriate substituted chalcones might be a new class of antileishmanial drugs. Images PMID:8109916

  11. Highly active antiretroviral therapy potently suppresses HIV infection in humanized Rag2-/-gammac-/- mice.

    PubMed

    Sango, Kaori; Joseph, Aviva; Patel, Mahesh; Osiecki, Kristin; Dutta, Monica; Goldstein, Harris

    2010-07-01

    Humanized Rag2(-/-)gamma(c)(-/-) mice (Hu-DKO mice) become populated with functional human T cells, B cells, and dendritic cells following transplantation with human hematopoietic stem cells (HSC) and represent an improved model for studying HIV infection in vivo. In the current study we demonstrated that intrasplenic inoculation of hu-DKO mice with HIV-1 initiated a higher level of HIV infection than intravenous or intraperitoneal inoculation, associated with a reciprocal decrease in peripheral CD4(+) T cells and increase in peripheral CD8(+) T cells. HIV infection by intrasplenic injection increased serum levels of human IgG and IgM including human IgM and IgG specific for HIV-1 gp120. There was a significant inverse correlation between the level of HIV-1 infection and the extent of CD4(+) T cell depletion. Highly active antiretroviral therapy (HAART) initiated 1 week after HIV-1 inoculation markedly suppressed HIV-1 infection and prevented CD4(+) T cell depletion. Taken together, these findings demonstrate that intrasplenic injection of hu-DKO mice with HIV is a more efficient route of HIV infection than intravenous or intraperitoneal injection and generates increased infection associated with an increased anti-HIV humoral response. This animal model can serve as a valuable in vivo model to study the efficacy of anti-HIV therapies.

  12. Measles Edmonston Vaccine Strain Derivatives have Potent Oncolytic Activity against Osteosarcoma

    PubMed Central

    Musibay, Evidio Domingo; Allen, Cory; Kurokawa, Cheyne; Hardcastle, Jayson J.; Aderca, Ileana; Msaouel, Pavlos; Bansal, Aditya; Jiang, Huailei; DeGrado, Timothy R.; Galanis, Evanthia

    2015-01-01

    Osteosarcoma is the most common primary bone tumor affecting children and young adults, and development of metastatic disease is associated with poor prognosis. The purpose of this study was to evaluate the antitumor efficacy of virotherapy with engineered measles virus (MV) vaccine strains in the treatment of osteosarcoma. Cell lines derived from pediatric patients with osteosarcoma (HOS, MG63, 143B, KHOS-312H, U2-OS and SJSA1) were examined for MV-GFP and MV-NIS gene expression and cytotoxicity as defined by syncytial formation, cell death, and eradication of cell monolayers: significant antitumor activity was demonstrated. Findings were correlated with in vivo efficacy in subcutaneous, orthotopic (tibial bone), and lung metastatic osteosarcoma xenografts treated with the MV derivative MV-NIS via the intratumoral (IT) or intravenous (IV) route. Following treatment, we observed decrease in tumor growth of subcutaneous xenografts (p=0.0374) and prolongation of survival in mice with orthotopic (p<0.0001) and pulmonary metastatic osteosarcoma tumors (p=0.0207). Expression of the NIS transgene in MV-NIS infected tumors allowed for SPECT-CT and PET-CT imaging of virus infected tumors in vivo. Our data support the translational potential of MV-based virotherapy approaches in the treatment of recurrent and metastatic osteosarcoma. PMID:25394505

  13. Multifunctional oligomer incorporation: a potent strategy to enhance the transfection activity of poly(l-lysine).

    PubMed

    Liu, Shuai; Yang, Jixiang; Ren, Hongqi; O'Keeffe-Ahern, Jonathan; Zhou, Dezhong; Zhou, Hao; Chen, Jiatong; Guo, Tianying

    2016-03-01

    Natural polycations, such as poly(l-lysine) (PLL) and chitosan (CS), have inherent superiority as non-viral vectors due to their unparalleled biocompatibility and biodegradability. However, the application was constrained by poor transfection efficiency and safety concerns. Since previous modification strategies greatly weakened the inherent advantages of natural polycations, developing a strategy for functional group introduction with broad applicability to enhance the transfection efficiency of natural polycations without compromising their cationic properties is imperative. Herein, two uncharged functional diblock oligomers P(DMAEL-b-NIPAM) and P(DMAEL-b-Vlm) were prepared from a lactose derivative, N-iso-propyl acrylamide (NIPAM) as well as 1-vinylimidazole (Vlm) and further functionalized with four small ligands folate, glutathione, cysteine and arginine, respectively, aiming to enhance the interactions of complexes with cells, which were quantified utilizing a quartz crystal microbalance (QCM) biosensor, circumventing the tedious material screening process of cell transfection. Upon incorporation with PLL and DNA, the multifunctional oligomers endow the formulated ternary complexes with great properties suitable for transfection, such as anti-aggregation in serum, destabilized endosome membrane, numerous functional sites for promoted endocytosis and therefore robust transfection activity. Furthermore, different from the conventional strategy of decreasing cytotoxicity by reducing the charge density, the multifunctional oligomer incorporation strategy maintains the highly positive charge density, which is essential for efficient cellular uptake. This system develops a new platform to modify natural polycations towards clinical gene therapy. PMID:26797493

  14. Tocotrienol-Rich Fraction from Rice Bran Demonstrates Potent Radiation Protection Activity.

    PubMed

    Krager, Kimberly J; Pineda, E Nathalie; Kharade, Sujay V; Kordsmeier, Mary; Howard, Luke; Breen, Philip J; Compadre, Cesar M; Hauer-Jensen, Martin; Aykin-Burns, Nukhet

    2015-01-01

    The vitamin E analogs δ-tocotrienol (DT3) and γ-tocotrienol (GT3) have significant protective and mitigative capacity against the detrimental effects of ionizing radiation (IR). However, the expense of purification limits their potential use. This study examined the tocotrienol-rich fraction of rice bran (TRFRB) isolated from rice bran deodorizer distillate, a rice oil refinement waste product, to determine its protective effects against IR induced oxidative damage and H2O2. Several cell lines were treated with tocotrienols or TRFRB prior to or following exposure to H2O2 or IR. To determine the radioprotective capacity cells were analyzed for morphology, mitochondrial bioenergetics, clonogenic survival, glutathione oxidation, cell cycle, and migration rate. TRFRB displayed similar antioxidant activity compared to pure tocotrienols. Cells pretreated with TRFRB or DT3 exhibited preserved cell morphology and mitochondrial respiration when exposed to H2O2. Oxidized glutathione was decreased in TRFRB treated cells exposed to IR. TRFRB reversed mitochondrial uncoupling and protected cells migration rates following IR exposure. The protective antioxidant capacity of TRFRB treated cells against oxidative injury was similar to that of purified DT3. TRFRB effectively protects normal cells against IR induced injury suggesting that rice bran distillate may be an inexpensive and abundant alternate source.

  15. Rhamnazin, a novel inhibitor of VEGFR2 signaling with potent antiangiogenic activity and antitumor efficacy

    SciTech Connect

    Yu, Yao; Cai, Wei; Pei, Chong-gang; Shao, Yi

    2015-03-20

    Anti-angiogenesis targeting vascular endothelial growth factor receptor 2 (VEGFR2) has emerged as an important tool for cancer therapy. The identification of new drugs from natural products has a long and successful history. In this study, we described a novel VEGFR2 inhibitor, rhamnazin, which inhibits tumor angiogenesis and growth. Rhamnazin significantly inhibited proliferation, migration and tube formation of human umbilical vascular endothelial cells (HUVECs) in vitro as well as inhibited sprouts formation of rat aorta ring. In addition, it inhibited vascular endothelial growth factor (VEGF)-induced phosphorylation of VEGFR2 and its downstream signaling regulator in HUVECs. Moreover, rhamnazin could directly inhibit proliferation of breast cancer cells MDA-MB-231 in vitro and in vivo. Oral administration of rhamnazin at a dose of 200 mg/kg/day could markedly inhibited human tumor xenograft growth and decreased microvessel densities (MVD) in tumor sections. Taken together, these preclinical evaluations suggest that rhamnazin inhibits angiogenesis and may be a promising anticancer drug candidate. - Highlights: • Rhamnazin inhibits the response of HUVECs to VEGF in vitro. • Rhamnazin inhibits VEGFR2 kinase activity and its downstream signaling. • Rhamnazin prevents the growth of MDA-MB-231 tumor and reduces micro-vessel density in vivo.

  16. Enabling the Discovery and Virtual Screening of Potent and Safe Antimicrobial Peptides. Simultaneous Prediction of Antibacterial Activity and Cytotoxicity.

    PubMed

    Kleandrova, Valeria V; Ruso, Juan M; Speck-Planche, Alejandro; Dias Soeiro Cordeiro, M Natália

    2016-08-01

    Antimicrobial peptides (AMPs) represent promising alternatives to fight against bacterial pathogens. However, cellular toxicity remains one of the main concerns in the early development of peptide-based drugs. This work introduces the first multitasking (mtk) computational model focused on performing simultaneous predictions of antibacterial activities, and cytotoxicities of peptides. The model was created from a data set containing 3592 cases, and it displayed accuracy higher than 96% for classifying/predicting peptides in both training and prediction (test) sets. The technique known as alanine scanning was computationally applied to illustrate the calculation of the quantitative contributions of the amino acids (in their respective positions of the sequence) to the biological effects of a defined peptide. A small library formed by 10 peptides was generated, where peptides were designed by considering the interpretations of the different descriptors in the mtk-computational model. All the peptides were predicted to exhibit high antibacterial activities against multiple bacterial strains, and low cytotoxicity against various cell types. The present mtk-computational model can be considered a very useful tool to support high throughput research for the discovery of potent and safe AMPs.

  17. Enabling the Discovery and Virtual Screening of Potent and Safe Antimicrobial Peptides. Simultaneous Prediction of Antibacterial Activity and Cytotoxicity.

    PubMed

    Kleandrova, Valeria V; Ruso, Juan M; Speck-Planche, Alejandro; Dias Soeiro Cordeiro, M Natália

    2016-08-01

    Antimicrobial peptides (AMPs) represent promising alternatives to fight against bacterial pathogens. However, cellular toxicity remains one of the main concerns in the early development of peptide-based drugs. This work introduces the first multitasking (mtk) computational model focused on performing simultaneous predictions of antibacterial activities, and cytotoxicities of peptides. The model was created from a data set containing 3592 cases, and it displayed accuracy higher than 96% for classifying/predicting peptides in both training and prediction (test) sets. The technique known as alanine scanning was computationally applied to illustrate the calculation of the quantitative contributions of the amino acids (in their respective positions of the sequence) to the biological effects of a defined peptide. A small library formed by 10 peptides was generated, where peptides were designed by considering the interpretations of the different descriptors in the mtk-computational model. All the peptides were predicted to exhibit high antibacterial activities against multiple bacterial strains, and low cytotoxicity against various cell types. The present mtk-computational model can be considered a very useful tool to support high throughput research for the discovery of potent and safe AMPs. PMID:27280735

  18. Potent neutralization of VEGF biological activities with a fully human antibody Fab fragment directed against VEGF receptor 2

    SciTech Connect

    Miao, H.-Q. . E-mail: hua-quan.miao@imclone.com; Hu, Kun; Jimenez, Xenia; Navarro, Elizabeth; Zhang, Haifan; Lu Dan; Ludwig, Dale L.; Balderes, Paul; Zhu Zhenping . E-mail: zhenping.zhu@imclone.com

    2006-06-23

    Compelling evidence suggest that vascular endothelial growth factor (VEGF) and its receptors, especially receptor 2 (VEGFR2, or kinase insert domain-containing receptor, KDR), play a critical role in angiogenesis under both physiological and pathological conditions, including cancer and angiogenic retinopathies such as age-related macular degeneration (AMD). To this end, inhibition of angiogenesis with antagonists to either VEGF or KDR has yielded significant therapeutic efficacy both in preclinical studies in animal models and in clinical trials in patients with cancer and AMD. We previously reported the identification of a high affinity, fully human anti-KDR antibody fragment, 1121B Fab, through a highly stringent affinity maturation process with a Fab originally isolated from a naive human antibody phage display library. In this study, we demonstrate that 1121B Fab is able to strongly block KDR/VEGF interaction, resulting in potent inhibition of an array of biological activities of VEGF, including activation of the receptor and its signaling pathway, intracellular calcium mobilization, and migration and proliferation of endothelial cells. Taken together, our data lend strong support to the further development of 1121B Fab fragment as an anti-angiogenesis agent in both cancer and angiogenic retinopathies.

  19. A novel small molecule agent displays potent anti-myeloma activity by inhibiting the JAK2-STAT3 signaling pathway

    PubMed Central

    Zhu, Jingyu; Xu, Yujia; Wang, Siyu; Xu, Xin; Ji, Peng; Yu, Yang; Cao, Biyin; Han, Kunkun; Hou, Tingjun; Xu, Zhuan; Kong, Yan; Jiang, Gaofeng; Tang, Xiaowen; Qiao, Chunhua; Mao, Xinliang

    2016-01-01

    The oncogenic STAT3 signaling pathway is emerging as a promising target for the treatment of multiple myeloma (MM). In the present study, we identified a novel STAT3 inhibitor SC99 in a target-based high throughput screen. SC99 inhibited JAK2-STAT3 activation but had no effects on other transcription factors such as NF-κB, and kinases such as AKT, ERK, and c-Src that are in association with STAT3 signaling pathway. Furthermore, SC99 downregulated the expression of STAT3-modulated genes, including Bcl-2, Bcl-xL, VEGF, cyclin D2, and E2F-1. By inhibiting the STAT3 signaling, SC99 induced MM cell apoptosis which could be partly abolished by the ectopic expression of STAT3. Furthermore, SC99 displayed potent anti-MM activity in two independent MM xenograft models in nude mice. Oral administration of SC99 led to marked decrease of tumor growth within 10 days at a daily dosage of 30 mg/kg, but did not raise toxic effects. Taken together, this study identified a novel oral JAK2/STAT3 inhibitor that could be developed as an anti-myeloma agent. PMID:26814430

  20. COH-203, a novel microtubule inhibitor, exhibits potent anti-tumor activity via p53-dependent senescence in hepatocellular carcinoma.

    PubMed

    Qi, Huan; Zuo, Dai-Ying; Bai, Zhao-Shi; Xu, Jing-Wen; Li, Zeng-Qiang; Shen, Qi-Rong; Wang, Zhi-Wei; Zhang, Wei-Ge; Wu, Ying-Liang

    2014-12-12

    5-(3-Hydroxy-4-methoxyphenyl)-4-(3,4,5-trimethoxyphenyl)-3H-1,2-dithiol-3-one (COH-203) is a novel synthesized analogue of combretastatin A-4 that can be classified as a microtubule inhibitor. In this study, we evaluated the anti-hepatoma effect of COH-203 in vitro and in vivo and explored the underlying molecular mechanisms. COH-203 was shown to be more effective in inhibiting the proliferation of liver cancer cells compared with normal liver cells. COH-203 also displayed potent anti-tumor activity in a hepatocellular carcinoma xenograft model without significant toxicity. Mechanistic studies demonstrated that treatment with COH-203 induced mitotic arrest by inhibiting tubulin polymerization in BEL-7402 liver cancer cells. Long-term COH-203 treatment in BEL-7402 cells led to mitotic slippage followed by senescence via the p14(Arf)-p53-p21 and p16(INK4α)-Rb pathways. Furthermore, suppression of p53 via pifithrin-α (p53 inhibitor) and p53-siRNA attenuated COH-203-induced senescence in BEL-7402 cells, suggesting that COH-203 induced senescence p53-dependently. In conclusion, we report for the first time that COH-203, one compound in the combretastatin family, promotes anti-proliferative activity through the induction of p-53 dependent senescence. Our findings will provide a molecular rationale for the development of COH-203 as a promising anti-tumor agent.

  1. Combined activation of the energy and cellular-defense pathways may explain the potent anti-senescence activity of methylene blue.

    PubMed

    Atamna, Hani; Atamna, Wafa; Al-Eyd, Ghaith; Shanower, Gregory; Dhahbi, Joseph M

    2015-12-01

    Methylene blue (MB) delays cellular senescence, induces complex-IV, and activates Keap1/Nrf2; however, the molecular link of these effects to MB is unclear. Since MB is redox-active, we investigated its effect on the NAD/NADH ratio in IMR90 cells. The transient increase in NAD/NADH observed in MB-treated cells triggered an investigation of the energy regulator AMPK. MB induced AMPK phosphorylation in a transient pattern, which was followed by the induction of PGC1α and SURF1: both are inducers of mitochondrial and complex-IV biogenesis. Subsequently MB-treated cells exhibited >100% increase in complex-IV activity and a 28% decline in cellular oxidants. The telomeres erosion rate was also significantly lower in MB-treated cells. A previous research suggested that the pattern of AMPK activation (i.e., chronic or transient) determines the AMPK effect on cell senescence. We identified that the anti-senescence activity of MB (transient activator) was 8-times higher than that of AICAR (chronic activator). Since MB lacked an effect on cell cycle, an MB-dependent change to cell cycle is unlikely to contribute to the anti-senescence activity. The current findings in conjunction with the activation of Keap1/Nrf2 suggest a synchronized activation of the energy and cellular defense pathways as a possible key factor in MB's potent anti-senescence activity.

  2. Combined activation of the energy and cellular-defense pathways may explain the potent anti-senescence activity of methylene blue

    PubMed Central

    Atamna, Hani; Atamna, Wafa; Al-Eyd, Ghaith; Shanower, Gregory; Dhahbi, Joseph M.

    2015-01-01

    Methylene blue (MB) delays cellular senescence, induces complex-IV, and activates Keap1/Nrf2; however, the molecular link of these effects to MB is unclear. Since MB is redox-active, we investigated its effect on the NAD/NADH ratio in IMR90 cells. The transient increase in NAD/NADH observed in MB-treated cells triggered an investigation of the energy regulator AMPK. MB induced AMPK phosphorylation in a transient pattern, which was followed by the induction of PGC1α and SURF1: both are inducers of mitochondrial and complex-IV biogenesis. Subsequently MB-treated cells exhibited >100% increase in complex-IV activity and a 28% decline in cellular oxidants. The telomeres erosion rate was also significantly lower in MB-treated cells. A previous research suggested that the pattern of AMPK activation (i.e., chronic or transient) determines the AMPK effect on cell senescence. We identified that the anti-senescence activity of MB (transient activator) was 8-times higher than that of AICAR (chronic activator). Since MB lacked an effect on cell cycle, an MB-dependent change to cell cycle is unlikely to contribute to the anti-senescence activity. The current findings in conjunction with the activation of Keap1/Nrf2 suggest a synchronized activation of the energy and cellular defense pathways as a possible key factor in MB's potent anti-senescence activity. PMID:26386875

  3. Breast Milk of HIV-Positive Mothers Has Potent and Species-Specific In Vivo HIV-Inhibitory Activity

    PubMed Central

    Wahl, Angela; Baker, Caroline; Spagnuolo, Rae Ann; Stamper, Lisa W.; Fouda, Genevieve G.; Permar, Sallie R.; Hinde, Katie; Kuhn, Louise; Bode, Lars; Aldrovandi, Grace M.

    2015-01-01

    ABSTRACT Despite the nutritional and health benefits of breast milk, breast milk can serve as a vector for mother-to-child HIV transmission. Most HIV-infected infants acquire HIV through breastfeeding. Paradoxically, most infants breastfed by HIV-positive women do not become infected. This is potentially attributed to anti-HIV factors in breast milk. Breast milk of HIV-negative women can inhibit HIV infection. However, the HIV-inhibitory activity of breast milk from HIV-positive mothers has not been evaluated. In addition, while significant differences in breast milk composition between transmitting and nontransmitting HIV-positive mothers have been correlated with transmission risk, the HIV-inhibitory activity of their breast milk has not been compared. This knowledge may significantly impact the design of prevention approaches in resource-limited settings that do not deny infants of HIV-positive women the health benefits of breast milk. Here, we utilized bone marrow/liver/thymus humanized mice to evaluate the in vivo HIV-inhibitory activity of breast milk obtained from HIV-positive transmitting and nontransmitting mothers. We also assessed the species specificity and biochemical characteristics of milk's in vivo HIV-inhibitory activity and its ability to inhibit other modes of HIV infection. Our results demonstrate that breast milk of HIV-positive mothers has potent HIV-inhibitory activity and indicate that breast milk can prevent multiple routes of infection. Most importantly, this activity is unique to human milk. Our results also suggest multiple factors in breast milk may contribute to its HIV-inhibitory activity. Collectively, our results support current recommendations that HIV-positive mothers in resource-limited settings exclusively breastfeed in combination with antiretroviral therapy. IMPORTANCE Approximately 240,000 children become infected with HIV annually, the majority via breastfeeding. Despite daily exposure to virus in breast milk, most infants

  4. Exploration of structure-activity relationships at the two C-terminal residues of potent 11mer Glucagon-Like Peptide-1 receptor agonist peptides via parallel synthesis.

    PubMed

    Haque, Tasir S; Martinez, Rogelio L; Lee, Ving G; Riexinger, Douglas G; Lei, Ming; Feng, Ming; Koplowitz, Barry; Mapelli, Claudio; Cooper, Christopher B; Zhang, Ge; Huang, Christine; Ewing, William R; Krupinski, John

    2010-07-01

    We report the identification of potent agonists of the Glucagon-Like Peptide-1 receptor (GLP-1R) via evaluation of two positional scanning libraries and a two-dimensional focused library, synthesized in part on SynPhase Lanterns. These compounds are 11 amino acid peptides containing several unnatural amino acids, including (in particular) analogs of biphenylalanine (Bip) at the two C-terminal positions. Typical activities of the most potent peptides in this class are in the picomolar range in an in vitro functional assay using human GLP-1 receptor.

  5. Rational design, synthesis, and structure-activity relationship of benzoxazolones: new potent mglu5 receptor antagonists based on the fenobam structure.

    PubMed

    Ceccarelli, Simona M; Jaeschke, Georg; Buettelmann, Bernd; Huwyler, Jörg; Kolczewski, Sabine; Peters, Jens-Uwe; Prinssen, Eric; Porter, Richard; Spooren, Will; Vieira, Eric

    2007-03-01

    A novel class of potent and stable mGlu5 receptor antagonists was developed by combining information from a high-throughput screening campaign with the structure of the known anxiolytic fenobam. Representative compounds from this class show favorable pharmacokinetic properties and are active in an in vivo model of anxiety.

  6. Synergistic anti-tumor therapy by a comb-like multifunctional antibody nanoarray with exceptionally potent activity

    NASA Astrophysics Data System (ADS)

    Li, Huafei; Sun, Yun; Chen, Di; Zhao, He; Zhao, Mengxin; Zhu, Xiandi; Ke, Changhong; Zhang, Ge; Jiang, Cheng; Zhang, Li; Zhang, Fulei; Wei, Huafeng; Li, Wei

    2015-10-01

    Simultaneously blocking multiple mediators offers new hope for the treatment of complex diseases. However, the curative potential of current combination therapy by chronological administration of separate monoclonal antibodies (mAbs) or multi-specific mAbs is still moderate due to inconvenient manipulation, low cooperative effectors, poor pharmacokinetics and insufficient tumor accumulation. Here, we describe a facile strategy that arms distinct mAbs with cooperative effectors onto a long chain to form a multicomponent comb-like nano mAb. Unlike dissociative parental mAbs, the multifunctional mAb nanoarray (PL-RB) constructed from type I/II anti-CD20 mAbs shows good pharmacokinetics. This PL-RB simultaneously targets distinct epitopes on a single antigen (Ag) and neighboring Ags on different lymphocytes. This unique intra- and intercellular Ag cross-linking endows the multifunctional mAb nanoarray with potent apoptosis activity. The exceptional apoptosis, complement-dependent cytotoxicity (CDC), antibody-dependent cellular cytotoxicity (ADCC) that are synchronously evoked by the nano PL-RB are further synergistically promoted via enhanced permeability and retention (EPR), which resulted in high intratumor accumulation and excellent anti-lymphoma efficiency.

  7. Peptidomic analysis of skin secretions from the bullfrog Lithobates catesbeianus (Ranidae) identifies multiple peptides with potent insulin-releasing activity.

    PubMed

    Mechkarska, Milena; Ojo, Opeolu O; Meetani, Mohammed A; Coquet, Laurent; Jouenne, Thierry; Abdel-Wahab, Yasser H A; Flatt, Peter R; King, Jay D; Conlon, J Michael

    2011-02-01

    Using a combination of reversed-phase HPLC and electrospray mass spectrometry, peptidomic analysis of norepinephrine-stimulated skin secretions of the American bullfrog Lithobates catesbeianus Shaw, 1802 led to the identification and characterization of five newly described peptides (ranatuerin-1CBb, ranatuerin-2CBc, and -CBd, palustrin-2CBa, and temporin-CBf) together with seven peptides previously isolated on the basis of their antimicrobial activity (ranatuerin-1CBa, ranatuerin-2CBa, brevinin-1CBa, and -1CBb, temporin-CBa, -CBb, and -CBd). The abilities of the most abundant of the purified peptides to stimulate the release of insulin from the rat BRIN-BD11 clonal β cell line were evaluated. Ranatuerin-2CBd (GFLDIIKNLGKTFAGHMLDKIRCTIGTCPPSP) was the most potent peptide producing a significant stimulation of insulin release (119% of basal rate, P<0.01) from BRIN-BD11 cells at a concentration of 30nM, with a maximum response (236% of basal rate, P<0.001) at a concentration of 3μM. Ranatuerin-2CBd did not stimulate release of the cytosolic enzyme, lactate dehydrogenase at concentrations up to 3μM, indicating that the integrity of the plasma membrane had been preserved. Brevinin-1CBb (FLPFIARLAAKVFPSIICSVTKKC) produced the maximum stimulation of insulin release (285% of basal rate, P<0.001 at 3μM) but the peptide was cytotoxic at this concentration. PMID:21087647

  8. Synergistic anti-tumor therapy by a comb-like multifunctional antibody nanoarray with exceptionally potent activity

    PubMed Central

    Li, Huafei; Sun, Yun; Chen, Di; Zhao, He; Zhao, Mengxin; Zhu, Xiandi; Ke, Changhong; Zhang, Ge; Jiang, Cheng; Zhang, Li; Zhang, Fulei; Wei, Huafeng; Li, Wei

    2015-01-01

    Simultaneously blocking multiple mediators offers new hope for the treatment of complex diseases. However, the curative potential of current combination therapy by chronological administration of separate monoclonal antibodies (mAbs) or multi-specific mAbs is still moderate due to inconvenient manipulation, low cooperative effectors, poor pharmacokinetics and insufficient tumor accumulation. Here, we describe a facile strategy that arms distinct mAbs with cooperative effectors onto a long chain to form a multicomponent comb-like nano mAb. Unlike dissociative parental mAbs, the multifunctional mAb nanoarray (PL-RB) constructed from type I/II anti-CD20 mAbs shows good pharmacokinetics. This PL-RB simultaneously targets distinct epitopes on a single antigen (Ag) and neighboring Ags on different lymphocytes. This unique intra- and intercellular Ag cross-linking endows the multifunctional mAb nanoarray with potent apoptosis activity. The exceptional apoptosis, complement-dependent cytotoxicity (CDC), antibody-dependent cellular cytotoxicity (ADCC) that are synchronously evoked by the nano PL-RB are further synergistically promoted via enhanced permeability and retention (EPR), which resulted in high intratumor accumulation and excellent anti-lymphoma efficiency. PMID:26508306

  9. P1-Substituted Symmetry-Based Human Immunodeficiency Virus Protease Inhibitors with Potent Antiviral Activity against Drug-Resistant Viruses

    SciTech Connect

    DeGoey, David A.; Grampovnik, David J.; Chen, Hui-Ju; Flosi, William J.; Klein, Larry L.; Dekhtyar, Tatyana; Stoll, Vincent; Mamo, Mulugeta; Molla, Akhteruzzaman; Kempf, Dale J.

    2013-03-07

    Because there is currently no cure for HIV infection, patients must remain on long-term drug therapy, leading to concerns over potential drug side effects and the emergence of drug resistance. For this reason, new and safe antiretroviral agents with improved potency against drug-resistant strains of HIV are needed. A series of HIV protease inhibitors (PIs) with potent activity against both wild-type (WT) virus and drug-resistant strains of HIV was designed and synthesized. The incorporation of substituents with hydrogen bond donor and acceptor groups at the P1 position of our symmetry-based inhibitor series resulted in significant potency improvements against the resistant mutants. By this approach, several compounds, such as 13, 24, and 29, were identified that demonstrated similar or improved potencies compared to 1 against highly mutated strains of HIV derived from patients who previously failed HIV PI therapy. Overall, compound 13 demonstrated the best balance of potency against drug resistant strains of HIV and oral bioavailability in pharmacokinetic studies. X-ray analysis of an HIV PI with an improved resistance profile bound to WT HIV protease is also reported.

  10. Knockdown of the small conductance Ca2+‐activated K+ channels is potently cytotoxic in breast cancer cell lines

    PubMed Central

    Abdulkareem, Zana Azeez; Gee, Julia MW

    2015-01-01

    Background and Purpose Small conductance calcium‐activated potassium (KCa2.x) channels have a widely accepted canonical function in regulating cellular excitability. In this study, we address a potential non‐canonical function of KCa2.x channels in breast cancer cell survival, using in vitro models. Experimental Approach The expression of all KCa2.x channel isoforms was initially probed using RT‐PCR, Western blotting and microarray analysis in five widely studied breast cancer cell lines. In order to assess the effect of pharmacological blockade and siRNA‐mediated knockdown of KCa2.x channels on these cell lines, we utilized MTS proliferation assays and also followed the corresponding expression of apoptotic markers. Key Results All of the breast cancer cell lines, regardless of their lineage or endocrine responsiveness, were highly sensitive to KCa2.x channel blockade. UCL1684 caused cytotoxicity, with LD50 values in the low nanomolar range, in all cell lines. The role of KCa2.x channels was confirmed using pharmacological inhibition and siRNA‐mediated knockdown. This reduced cell viability and also reduced expression of Bcl‐2 but increased expression of active caspase‐7 and caspase‐9. Complementary to these results, a variety of cell lines can be protected from apoptosis induced by staurosporine using the KCa2.x channel activator CyPPA. Conclusions and Implications In addition to a well‐established role for KCa2.x channels in migration, blockade of these channels was potently cytotoxic in breast cancer cell lines, pointing to modulation of KCa2.x channels as a potential therapeutic approach to breast cancer. PMID:26454020

  11. Fibroblast growth factor, but not activin, is a potent activator of mitogen-activated protein kinase in Xenopus explants.

    PubMed Central

    Graves, L M; Northrop, J L; Potts, B C; Krebs, E G; Kimelman, D

    1994-01-01

    Isolated explants from the animal hemisphere of Xenopus embryos were incubated with Xenopus basic fibroblast growth factor (XbFGF) or human activin A. XbFGF incubation resulted in the rapid activation of mitogen-activated protein kinase (MAPK) and ribosomal S6 protein kinase (pp90rsk) in a dose-dependent manner with the highest levels of activation occurring at 50 ng/ml. Maximal activation occurred within 6-10 min after the addition of growth factor, and the activity of both kinases declined to unstimulated levels after 30 min. Activin was unable to activate either MAPK or pp90rsk in the Xenopus explants to a substantial level, although it induced dorsal mesoderm better than XbFGF under the same experimental conditions. The regulatory protein Xwnt-8 did not activate MAPK, nor did it enhance the activation of MAPK by XbFGF. XbFGF was able to activate MAPK through at least the midgastrula stage, suggesting that this family of growth factors may have a role in gastrula-stage events. Images PMID:7510404

  12. The angular structure of ONC201, a TRAIL pathway-inducing compound, determines its potent anti-cancer activity

    PubMed Central

    Wagner, Jessica; Kline, Christina Leah; Pottorf, Richard S.; Nallaganchu, Bhaskara Rao; Olson, Gary L.; Dicker, David T.; Allen, Joshua E.; El-Deiry, Wafik S.

    2014-01-01

    We previously identified TRAIL-inducing compound 10 (TIC10), also known as NSC350625 or ONC201, from a NCI chemical library screen as a small molecule that has potent anti-tumor efficacy and a benign safety profile in preclinical cancer models. The chemical structure that was originally published by Stahle, et. al. in the patent literature was described as an imidazo[1,2-a]pyrido[4,3-d]pyrimidine derivative. The NCI and others generally accepted this as the correct structure, which was consistent with the mass spectrometry analysis outlined in the publication by Allen et. al. that first reported the molecule's anticancer properties. A recent publication demonstrated that the chemical structure of ONC201 material from the NCI is an angular [3,4-e] isomer of the originally disclosed, linear [4,3-d] structure. Here we confirm by NMR and X-ray structural analysis of the dihydrochloride salt form that the ONC201 material produced by Oncoceutics is the angular [3,4-e] structure and not the linear structure originally depicted in the patent literature and by the NCI. Similarly, in accordance with our biological evaluation, the previously disclosed anti-cancer activity is associated with the angular structure and not the linear isomer. Together these studies confirm that ONC201, produced by Oncoceutics or obtained from the NCI, possesses an angular [3,4-e] structure that represents the highly active anti-cancer compound utilized in prior preclinical studies and now entering clinical trials in advanced cancers. PMID:25587031

  13. Antitumor activity of a potent MEK inhibitor, TAK-733, against colorectal cancer cell lines and patient derived xenografts

    PubMed Central

    Lieu, Christopher H.; Klauck, Peter J.; Henthorn, Patrick K.; Tentler, John J.; Tan, Aik-Choon; Spreafico, Anna; Selby, Heather M.; Britt, Blair C.; Bagby, Stacey M.; Arcaroli, John J.; Messersmith, Wells A.; Pitts, Todd M.; Eckhardt, S. Gail

    2015-01-01

    Background CRC is a significant cause of cancer mortality, and new therapies are needed for patients with advanced disease. TAK-733 is a highly potent and selective investigational novel MEK allosteric site inhibitor. Materials and Methods In a preclinical study of TAK-733, a panel of CRC cell lines were exposed to varying concentrations of the agent for 72 hours followed by a sulforhodamine B assay. Twenty patient-derived colorectal cancer xenografts were then treated with TAK-733 in vivo. Tumor growth inhibition index (TGII) was assessed to evaluate the sensitivity of the CRC explants to TAK-733 while linear regression was utilized to investigate the predictive effects of genotype on the TGII of explants. Results Fifty-four CRC cell lines were exposed to TAK-733, while 42 cell lines were deemed sensitive across a broad range of mutations. Eighty-two percent of the cell lines within the sensitive subset were BRAF or KRAS/NRAS mutant, whereas 80% of the cell lines within the sensitive subset were PIK3CA WT. Twenty patient-derived human tumor CRC explants were then treated with TAK-733. In total, 15 primary human tumor explants were found to be sensitive to TAK-733 (TGII ≤ 20%), including 9 primary human tumor explants that exhibited tumor regression (TGII > 100%). Explants with a BRAF/KRAS/NRAS mutant and PIK3CA wild-type genotype demonstrated increased sensitivity to TAK-733 with a median TGII of −6%. MEK-response gene signatures also correlated with responsiveness to TAK-733 in KRAS-mutant CRC. Conclusions The MEK inhibitor TAK-733 demonstrated robust antitumor activity against CRC cell lines and patient-derived tumor explants. While the preclinical activity observed in this study was considerable, single-agent efficacy in the clinic has been limited in CRC, supporting the use of these models in an iterative manner to elucidate resistance mechanisms that can guide rational combination strategies. PMID:26439693

  14. LLY-507, a Cell-active, Potent, and Selective Inhibitor of Protein-lysine Methyltransferase SMYD2*

    PubMed Central

    Nguyen, Hannah; Allali-Hassani, Abdellah; Antonysamy, Stephen; Chang, Shawn; Chen, Lisa Hong; Curtis, Carmen; Emtage, Spencer; Fan, Li; Gheyi, Tarun; Li, Fengling; Liu, Shichong; Martin, Joseph R.; Mendel, David; Olsen, Jonathan B.; Pelletier, Laura; Shatseva, Tatiana; Wu, Song; Zhang, Feiyu Fred; Arrowsmith, Cheryl H.; Brown, Peter J.; Campbell, Robert M.; Garcia, Benjamin A.; Barsyte-Lovejoy, Dalia; Mader, Mary; Vedadi, Masoud

    2015-01-01

    SMYD2 is a lysine methyltransferase that catalyzes the monomethylation of several protein substrates including p53. SMYD2 is overexpressed in a significant percentage of esophageal squamous primary carcinomas, and that overexpression correlates with poor patient survival. However, the mechanism(s) by which SMYD2 promotes oncogenesis is not understood. A small molecule probe for SMYD2 would allow for the pharmacological dissection of this biology. In this report, we disclose LLY-507, a cell-active, potent small molecule inhibitor of SMYD2. LLY-507 is >100-fold selective for SMYD2 over a broad range of methyltransferase and non-methyltransferase targets. A 1.63-Å resolution crystal structure of SMYD2 in complex with LLY-507 shows the inhibitor binding in the substrate peptide binding pocket. LLY-507 is active in cells as measured by reduction of SMYD2-induced monomethylation of p53 Lys370 at submicromolar concentrations. We used LLY-507 to further test other potential roles of SMYD2. Mass spectrometry-based proteomics showed that cellular global histone methylation levels were not significantly affected by SMYD2 inhibition with LLY-507, and subcellular fractionation studies indicate that SMYD2 is primarily cytoplasmic, suggesting that SMYD2 targets a very small subset of histones at specific chromatin loci and/or non-histone substrates. Breast and liver cancers were identified through in silico data mining as tumor types that display amplification and/or overexpression of SMYD2. LLY-507 inhibited the proliferation of several esophageal, liver, and breast cancer cell lines in a dose-dependent manner. These findings suggest that LLY-507 serves as a valuable chemical probe to aid in the dissection of SMYD2 function in cancer and other biological processes. PMID:25825497

  15. COH-203, a novel microtubule inhibitor, exhibits potent anti-tumor activity via p53-dependent senescence in hepatocellular carcinoma

    SciTech Connect

    Qi, Huan; Zuo, Dai-Ying; Bai, Zhao-Shi; Xu, Jing-Wen; Li, Zeng-Qiang; Shen, Qi-Rong; Wang, Zhi-Wei; Zhang, Wei-Ge; Wu, Ying-Liang

    2014-12-12

    Highlights: • COH-203 exhibits anti-hepatoma effects in vitro and in vivo with low toxicity. • COH-203 inhibits tubulin polymerization. • COH-203 induces mitotic arrest followed by mitotic slippage in BEL-7402 cells. • COH-203 induces p53-dependent senescence in BEL-7402 cells. - Abstract: 5-(3-Hydroxy-4-methoxyphenyl)-4-(3,4,5-trimethoxyphenyl)-3H-1, 2-dithiol-3-one (COH-203) is a novel synthesized analogue of combretastatin A-4 that can be classified as a microtubule inhibitor. In this study, we evaluated the anti-hepatoma effect of COH-203 in vitro and in vivo and explored the underlying molecular mechanisms. COH-203 was shown to be more effective in inhibiting the proliferation of liver cancer cells compared with normal liver cells. COH-203 also displayed potent anti-tumor activity in a hepatocellular carcinoma xenograft model without significant toxicity. Mechanistic studies demonstrated that treatment with COH-203 induced mitotic arrest by inhibiting tubulin polymerization in BEL-7402 liver cancer cells. Long-term COH-203 treatment in BEL-7402 cells led to mitotic slippage followed by senescence via the p14{sup Arf}–p53–p21 and p16{sup INK4α}–Rb pathways. Furthermore, suppression of p53 via pifithrin-α (p53 inhibitor) and p53-siRNA attenuated COH-203-induced senescence in BEL-7402 cells, suggesting that COH-203 induced senescence p53-dependently. In conclusion, we report for the first time that COH-203, one compound in the combretastatin family, promotes anti-proliferative activity through the induction of p-53 dependent senescence. Our findings will provide a molecular rationale for the development of COH-203 as a promising anti-tumor agent.

  16. The Epithelial Danger Signal IL-1α Is a Potent Activator of Fibroblasts and Reactivator of Intestinal Inflammation

    PubMed Central

    Scarpa, Melania; Kessler, Sean; Sadler, Tammy; West, Gail; Homer, Craig; McDonald, Christine; de la Motte, Carol; Fiocchi, Claudio; Stylianou, Eleni

    2016-01-01

    Intestinal epithelial cell (IEC) death is typical of inflammatory bowel disease (IBD). We investigated: i) whether IEC–released necrotic cell products (proinflammatory mediators) amplify mucosal inflammation, ii) the capacity of necrotic cell lysates from HT29 cells or human IECs to induce human intestinal fibroblasts' (HIF) production of IL-6 and IL-8, and iii) whether IL-1α, released by injured colonocytes, exacerbated experimental IBD. Necrotic cell lysates potently induced HIF IL-6 and IL-8 production independent of Toll-like receptors 2 and 4, receptor for advanced glycation end-products, high-mobility group box 1, uric acid, IL-33, or inflammasome activation. IL-1α was the key IEC-derived necrotic cell product involved in HIF cytokine production. IL-1α–positive cells were identified in the epithelium in human IBD and dextran sulfate sodium (DSS)-induced colitis. IL-1α was detected in the stool of colitic mice before IL-1β. IL-1α enemas reactivated inflammation after DSS colitis recovery, induced IL-1 receptor expression in subepithelial fibroblasts, and activated de novo inflammation even in mice without overt colitis, after the administration of low-dose DSS. IL-1α amplifies gut inflammation by inducing cytokine production by mesenchymal cells. IL-1α–mediated IEC–fibroblast interaction may be involved in amplifying and perpetuating inflammation, even without obvious intestinal damage. IL-1α may be a target for treating early IBD or preventing the reactivation of IBD. PMID:25864926

  17. Synthesis and Evaluation of 1,5-Disubstituted Tetrazoles as Rigid Analogues of Combretastatin A-4 with Potent Antiproliferative and Antitumor Activity

    PubMed Central

    Romagnoli, Romeo; Baraldi, Pier Giovanni; Salvador, Maria Kimatrai; Preti, Delia; Tabrizi, Mojgan Aghazadeh; Brancale, Andrea; Fu, Xian-Hua; Li, Jun; Zhang, Su-Zhan; Hamel, Ernest; Bortolozzi, Roberta; Basso, Giuseppe; Viola, Giampietro

    2012-01-01

    Tubulin, the major structural component of microtubules, is a target for the development of anticancer agents. Two series of 1,5-diaryl substituted 1,2,3,4-tetrazoles were concisely synthesized, using a palladium-catalyzed cross-coupling reaction, and identified as potent antiproliferative agents and novel tubulin polymerization inhibitors that act at the colchicine site. SAR analysis indicated that compounds with a 4-ethoxyphenyl group at the N-1 or C-5 position of the 1,2,3,4-tetrazole ring exhibited maximal activity. Several of these compounds also had potent activity in inhibiting the growth of multidrug resistant cells overexpressing P-glycoprotein. Active compounds induced apoptosis through the mitochondrial pathway with activation of caspase-9 and caspase-3. Furthermore, compound 4l significantly reduced in vivo the growth of the HT-29 xenograft in a nude mouse model, suggesting that 4l is a promising new antimitotic agent with clinical potential. PMID:22136312

  18. Synthesis and evaluation of 1,5-disubstituted tetrazoles as rigid analogues of combretastatin A-4 with potent antiproliferative and antitumor activity.

    PubMed

    Romagnoli, Romeo; Baraldi, Pier Giovanni; Salvador, Maria Kimatrai; Preti, Delia; Aghazadeh Tabrizi, Mojgan; Brancale, Andrea; Fu, Xian-Hua; Li, Jun; Zhang, Su-Zhan; Hamel, Ernest; Bortolozzi, Roberta; Basso, Giuseppe; Viola, Giampietro

    2012-01-12

    Tubulin, the major structural component of microtubules, is a target for the development of anticancer agents. Two series of 1,5-diaryl substituted 1,2,3,4-tetrazoles were concisely synthesized, using a palladium-catalyzed cross-coupling reaction, and identified as potent antiproliferative agents and novel tubulin polymerization inhibitors that act at the colchicine site. SAR analysis indicated that compounds with a 4-ethoxyphenyl group at the N-1 or C-5 position of the 1,2,3,4-tetrazole ring exhibited maximal activity. Several of these compounds also had potent activity in inhibiting the growth of multidrug resistant cells overexpressing P-glycoprotein. Active compounds induced apoptosis through the mitochondrial pathway with activation of caspase-9 and caspase-3. Furthermore, compound 4l significantly reduced in vivo the growth of the HT-29 xenograft in a nude mouse model, suggesting that 4l is a promising new antimitotic agent with clinical potential.

  19. Discovery of 2-(4-sulfonamidophenyl)-indole 3-carboxamides as potent and selective inhibitors with broad hepatitis C virus genotype activity targeting HCV NS4B.

    PubMed

    Zhang, Nanjing; Turpoff, Anthony; Zhang, Xiaoyan; Huang, Song; Liu, Yalei; Almstead, Neil; Njoroge, F George; Gu, Zhengxian; Graci, Jason; Jung, Stephen P; Pichardo, John; Colacino, Joseph; Lahser, Fred; Ingravallo, Paul; Weetall, Marla; Nomeir, Amin; Karp, Gary M

    2016-01-15

    A novel series of 2-(4-sulfonamidophenyl)-indole 3-carboxamides was identified and optimized for activity against the HCV genotype 1b replicon resulting in compounds with potent and selective activity. Further evaluation of this series demonstrated potent activity across HCV genotypes 1a, 2a and 3a. Compound 4z had reduced activity against HCV genotype 1b replicons containing single mutations in the NS4B coding sequence (F98C and V105M) indicating that NS4B is the target. This novel series of 2-(4-sulfonamidophenyl)-indole 3-carboxamides serves as a promising starting point for a pan-genotype HCV discovery program.

  20. Platelet-activating factor is a potent pyrogen and cryogen, but it does not mediate lipopolysaccharide fever or hypothermia.

    PubMed

    Steiner, Alexandre A; Romanovsky, Andrej A

    2015-01-01

    We examined whether platelet-activating factor (PAF) and its receptor mediate lipopolysaccharide (LPS)-induced fever and hypothermia in rats. Two highly potent, structurally distinct antagonists of the PAF receptor, CV6209 and WEB2086, were used. At a neutral ambient temperature (Ta) of 30ºC, administration of LPS at a low (10 μg/kg, i.v.) or high (1,000 μg/kg, i.v.) dose resulted in fever. The response to the high dose was turned into hypothermia at a subneutral Ta of 22ºC. Neither LPS-induced fever nor hypothermia was affected by pretreatment with CV6209 (5 mg/kg, i.v.) or WEB2086 (5 mg/kg, i.v.). However, both PAF antagonists were efficacious in blocking the thermoregulatory response caused by PAF (334 pmol/kg/min, 1 h, i.v.), regardless of whether the response was a fever (at 30ºC) or hypothermia (at 22ºC). Additional experiments showed that the thermoregulatory responses to LPS and PAF are also distinct in terms of their mediation by prostaglandins. Neither PAF fever nor PAF hypothermia was affected by pretreatment with the cyclooxygenase-2 inhibitor SC236 (5 mg/kg, i.p.), which is known to abrogate LPS fever. The responses to PAF were also unaffected by pretreatment with the cyclooxygenase-1 inhibitor SC560 (5 mg/kg, i.p.), which is known to attenuate LPS hypothermia. In conclusion, PAF infusion at a picomolar dose causes fever at thermoneutrality but hypothermia in a subthermoneutral environment, both responses being dependent on the PAF receptor and independent of prostaglandins. However, the PAF receptor does not mediate LPS-induced fever or hypothermia, thus challenging the dogma that PAF is an upstream mediator of responses to LPS. PMID:27227073

  1. Parallel functional activity profiling reveals valvulopathogens are potent 5-hydroxytryptamine(2B) receptor agonists: implications for drug safety assessment.

    PubMed

    Huang, Xi-Ping; Setola, Vincent; Yadav, Prem N; Allen, John A; Rogan, Sarah C; Hanson, Bonnie J; Revankar, Chetana; Robers, Matt; Doucette, Chris; Roth, Bryan L

    2009-10-01

    Drug-induced valvular heart disease (VHD) is a serious side effect of a few medications, including some that are on the market. Pharmacological studies of VHD-associated medications (e.g., fenfluramine, pergolide, methysergide, and cabergoline) have revealed that they and/or their metabolites are potent 5-hydroxytryptamine(2B) (5-HT(2B)) receptor agonists. We have shown that activation of 5-HT(2B) receptors on human heart valve interstitial cells in vitro induces a proliferative response reminiscent of the fibrosis that typifies VHD. To identify current or future drugs that might induce VHD, we screened approximately 2200 U.S. Food and Drug Administration (FDA)-approved or investigational medications to identify 5-HT(2B) receptor agonists, using calcium-based high-throughput screening. Of these 2200 compounds, 27 were 5-HT(2B) receptor agonists (hits); 14 of these had previously been identified as 5-HT(2B) receptor agonists, including seven bona fide valvulopathogens. Six of the hits (guanfacine, quinidine, xylometazoline, oxymetazoline, fenoldopam, and ropinirole) are approved medications. Twenty-three of the hits were then "functionally profiled" (i.e., assayed in parallel for 5-HT(2B) receptor agonism using multiple readouts to test for functional selectivity). In these assays, the known valvulopathogens were efficacious at concentrations as low as 30 nM, whereas the other compounds were less so. Hierarchical clustering analysis of the pEC(50) data revealed that ropinirole (which is not associated with valvulopathy) was clearly segregated from known valvulopathogens. Taken together, our data demonstrate that patterns of 5-HT(2B) receptor functional selectivity might be useful for identifying compounds likely to induce valvular heart disease. PMID:19570945

  2. Platelet-activating factor is a potent pyrogen and cryogen, but it does not mediate lipopolysaccharide fever or hypothermia

    PubMed Central

    Steiner, Alexandre A; Romanovsky, Andrej A

    2015-01-01

    We examined whether platelet-activating factor (PAF) and its receptor mediate lipopolysaccharide (LPS)-induced fever and hypothermia in rats. Two highly potent, structurally distinct antagonists of the PAF receptor, CV6209 and WEB2086, were used. At a neutral ambient temperature (Ta) of 30ºC, administration of LPS at a low (10 μg/kg, i.v.) or high (1,000 μg/kg, i.v.) dose resulted in fever. The response to the high dose was turned into hypothermia at a subneutral Ta of 22ºC. Neither LPS-induced fever nor hypothermia was affected by pretreatment with CV6209 (5 mg/kg, i.v.) or WEB2086 (5 mg/kg, i.v.). However, both PAF antagonists were efficacious in blocking the thermoregulatory response caused by PAF (334 pmol/kg/min, 1 h, i.v.), regardless of whether the response was a fever (at 30ºC) or hypothermia (at 22ºC). Additional experiments showed that the thermoregulatory responses to LPS and PAF are also distinct in terms of their mediation by prostaglandins. Neither PAF fever nor PAF hypothermia was affected by pretreatment with the cyclooxygenase-2 inhibitor SC236 (5 mg/kg, i.p.), which is known to abrogate LPS fever. The responses to PAF were also unaffected by pretreatment with the cyclooxygenase-1 inhibitor SC560 (5 mg/kg, i.p.), which is known to attenuate LPS hypothermia. In conclusion, PAF infusion at a picomolar dose causes fever at thermoneutrality but hypothermia in a subthermoneutral environment, both responses being dependent on the PAF receptor and independent of prostaglandins. However, the PAF receptor does not mediate LPS-induced fever or hypothermia, thus challenging the dogma that PAF is an upstream mediator of responses to LPS. PMID:27227073

  3. DSR-98776, a novel selective mGlu5 receptor negative allosteric modulator with potent antidepressant and antimanic activity.

    PubMed

    Kato, Taro; Takata, Makoto; Kitaichi, Maiko; Kassai, Momoe; Inoue, Mitsuhiro; Ishikawa, Chihiro; Hirose, Wataru; Yoshida, Kozo; Shimizu, Isao

    2015-06-15

    Modulation of monoaminergic systems has been the main stream of treatment for patients with mood disorders. However, recent evidence suggests that the glutamatergic system plays an important role in the pathophysiology of these disorders. This study pharmacologically characterized a structurally novel metabotropic glutamate 5 (mGlu5) receptor negative allosteric modulator, DSR-98776, and evaluated its effect on rodent models of depression and mania. First, DSR-98776 in vitro profile was assessed using intracellular calcium and radioligand binding assays. This compound showed dose-dependent inhibitory activity for mGlu5 receptors by binding to the same allosteric site as 2-methyl-6-(phenylethynyl)-pyridine (MPEP), a known mGlu5 inhibitor. The in vivo therapeutic benefits of DSR-98776 were evaluated in common rodent models of depression and mania. In the rat forced swimming test, DSR-98776 (1-3mg/kg) significantly reduced rats immobility time after treatment for 7 consecutive days, while paroxetine (3 and 10mg/kg) required administration for 2 consecutive weeks to reduce rats immobility time. In the mouse forced swimming test, acute administration of DSR-98776 (10-30 mg/kg) significantly reduced immobility time. This effect was not influenced by 4-chloro-DL-phenylalanine methyl ester hydrochloride-induced 5-HT depletion. Finally, DSR-98776 (30 mg/kg) significantly decreased methamphetamine/chlordiazepoxide-induced hyperactivity in mice, which reflects this compound antimanic-like effect. These results indicate that DSR-98776 acts as an orally potent antidepressant and antimanic in rodent models and can be a promising therapeutic option for the treatment of a broad range of mood disorders with depressive and manic states. PMID:25823809

  4. Design, synthesis, and antibacterial activities of neomycin-lipid conjugates: polycationic lipids with potent gram-positive activity.

    PubMed

    Bera, Smritilekha; Zhanel, George G; Schweizer, Frank

    2008-10-01

    Aminoglycoside antibiotics and cationic detergents constitute two classes of clinically important drugs and antiseptics. Their bacteriological and clinical efficacy, however, has decreased recently due to antibiotic resistance. We have synthesized aminoglycoside-lipid conjugates in which the aminoglycoside neomycin forms the cationic headgroup of a polycationic detergent. Our results show that neomycin-C16 and neomycin-C20 conjugates exhibit strong Gram-positive activity but reduced Gram-negative activity. The MIC of neomycin-C16 (C20) conjugates against methicillin-resistant Staphylococcus aureus (MRSA) is comparable to clinically used antiseptics.

  5. Design and synthesis of novel PEG-conjugated 20(S)-camptothecin sulfonylamidine derivatives with potent in vitro antitumor activity via Cu-catalyzed three-component reaction.

    PubMed

    Song, Zi-Long; Chen, Hai-Le; Wang, Yu-Han; Goto, Masuo; Gao, Wen-Jing; Cheng, Pi-Le; Morris-Natschke, Susan L; Liu, Ying-Qian; Zhu, Gao-Xiang; Wang, Mei-Juan; Lee, Kuo-Hsiung

    2015-07-01

    In our continuing search for camptothecin (CPT)-derived antitumor drugs, novel structurally diverse PEG-based 20(S)-CPT sulfonylamidine derivatives were designed, synthesized via a Cu-multicomponent reaction (MCR), and evaluated for cytotoxicity against four human tumor cell lines (A-549, MDA-MB-231, KB, and KBvin). All of the derivatives showed promising in vitro cytotoxic activity against the tested tumor cell lines, and were more potent than irinotecan. Significantly, these derivatives exhibited comparable cytotoxicity against KBvin, while irinotecan was less active against this cell line. With a concise efficient synthesis and potent cytotoxic profiles, especially significant activity towards KBvin, these compounds merit further development as a new generation of CPT-derived PEG-conjugated drug candidates.

  6. Discovery of a novel COX-2 inhibitor as an orally potent anti-pyretic and anti-inflammatory drug: design, synthesis, and structure-activity relationship.

    PubMed

    Hayashi, Shigeo; Sumi, Yoko; Ueno, Naomi; Murase, Akio; Takada, Junji

    2011-10-01

    Cyclooxygenase (COX) has been considered as a significant pharmacological target because of its pivotal roles in the prostaglandin biosynthesis and following cascades that lead to various (patho)physiological effects. Non-steroidal anti-inflammatory drugs (NSAIDs) that suppress COX activities have been used clinically for the treatment of fever, inflammation, and pain; however, nonselective COX inhibitors exhibit serious side-effects such as gastrointestinal damage because of their inhibitory activities against COX-1. Thus, COX-1 is constitutive and expressed ubiquitously and serves a housekeeping role, while COX-2 is inducible or upregulated by inflammatory/injury stimuli such as interleukin-1β, tumor necrosis factor-α, and lipopolysaccharide in macrophage, monocyte, synovial, liver, and lung, and is associated with prostaglandin E₂ and prostacyclin production that evokes or sustains systemic/peripheral inflammatory symptoms. Also, hypersensitivity of aspirin is a significant concern clinically. Hence, design, synthesis, and structure-activity relationship of [2-{[(4-substituted)-pyridin-2-yl]carbonyl}-(6- or 5-substituted)-1H-indol-3-yl]acetic acid analogues were investigated to discover novel acid-type COX-2 inhibitor as an orally potent new-class anti-pyretic and anti-inflammatory drug. As significant findings, compounds 1-3 demonstrated potent COX-2 inhibitory activities with high selectivities for COX-2 over COX-1 in human cells or whole-blood in vitro, and demonstrated orally potent anti-pyretic activity against lipopolysaccharide-induced systemic-inflammatory fever model in F344 rats. Also compound 1 demonstrated orally potent anti-inflammatory activity against edema formation and a suppressive effect against PGE₂ production in carrageenan-induced peripheral-inflammation model on the paw of SD rats. These results suggest that compounds 1-3 are potential agents for the treatment of inflammatory disease and are useful for further pharmacological COX-2

  7. EBI-907, a novel BRAF(V600E) inhibitor, has potent oral anti-tumor activity and a broad kinase selectivity profile.

    PubMed

    Zhang, Jiayin; Lu, Biao; Liu, Dong; Shen, Ru; Yan, Yinfa; Yang, Liuqing; Zhang, Minsheng; Zhang, Lei; Cao, Guoqing; Cao, Hu; Fu, Beibei; Gong, Aishen; Sun, Qiming; Wan, Hong; Zhang, Lianshan; Tao, Weikang; Cao, Jingsong

    2016-01-01

    The oncogenic mutation of BRAF(V600E) has been found in approximately 8% of all human cancers, including more than 60% of melanoma and 10% of colorectal cancers. The clinical proof of concept in treating BRAF(V600E)-driving melanoma patients with the BRAF inhibitors has been well established. We have sought to identify and develop novel BRAF(V600E) inhibitors with more favorable profiles. Our chemistry effort has led to the discovery of EBI-907 as a novel BRAF(V600E) inhibitor with potent anti-tumor activity in vitro and in vivo. In a LanthaScreen BRAF(V600E) kinase assay, EBI-907 showed an IC50 of 4.8 nM, which is >10 -fold more potent than Vemurafenib (IC50 = 58.5 nM). In addition, EBI-907 showed a broader kinase selectivity profile, with potent activity against a number of important oncogenic kinases including FGFR1-3, RET, c-Kit, and PDGFRb. Concomitant with such properties, EBI-907 exhibits potent and selective cytotoxicity against a broader range of BRAF(V600E)-dependent cell lines including certain colorectal cancer cell lines with innate resistance to Vemurafenib. In BRAF(V600E)-dependent human Colo-205 and A375 tumor xenograft mouse models, EBI-907 caused a marked tumor regression in a dose-dependent manner, with superior efficacy to Vemurafenib. Our results also showed that combination with EGFR or MEK inhibitor enhanced the potency of EBI-907 in cell lines with innate or acquired resistance to BRAF inhibition alone. Our findings present EBI-907 as a potent and promising BRAF inhibitor, which might be useful in broader indications. PMID:26810733

  8. EBI-907, a novel BRAF(V600E) inhibitor, has potent oral anti-tumor activity and a broad kinase selectivity profile.

    PubMed

    Zhang, Jiayin; Lu, Biao; Liu, Dong; Shen, Ru; Yan, Yinfa; Yang, Liuqing; Zhang, Minsheng; Zhang, Lei; Cao, Guoqing; Cao, Hu; Fu, Beibei; Gong, Aishen; Sun, Qiming; Wan, Hong; Zhang, Lianshan; Tao, Weikang; Cao, Jingsong

    2016-01-01

    The oncogenic mutation of BRAF(V600E) has been found in approximately 8% of all human cancers, including more than 60% of melanoma and 10% of colorectal cancers. The clinical proof of concept in treating BRAF(V600E)-driving melanoma patients with the BRAF inhibitors has been well established. We have sought to identify and develop novel BRAF(V600E) inhibitors with more favorable profiles. Our chemistry effort has led to the discovery of EBI-907 as a novel BRAF(V600E) inhibitor with potent anti-tumor activity in vitro and in vivo. In a LanthaScreen BRAF(V600E) kinase assay, EBI-907 showed an IC50 of 4.8 nM, which is >10 -fold more potent than Vemurafenib (IC50 = 58.5 nM). In addition, EBI-907 showed a broader kinase selectivity profile, with potent activity against a number of important oncogenic kinases including FGFR1-3, RET, c-Kit, and PDGFRb. Concomitant with such properties, EBI-907 exhibits potent and selective cytotoxicity against a broader range of BRAF(V600E)-dependent cell lines including certain colorectal cancer cell lines with innate resistance to Vemurafenib. In BRAF(V600E)-dependent human Colo-205 and A375 tumor xenograft mouse models, EBI-907 caused a marked tumor regression in a dose-dependent manner, with superior efficacy to Vemurafenib. Our results also showed that combination with EGFR or MEK inhibitor enhanced the potency of EBI-907 in cell lines with innate or acquired resistance to BRAF inhibition alone. Our findings present EBI-907 as a potent and promising BRAF inhibitor, which might be useful in broader indications.

  9. Anti-cariogenic effect of a cetylpyridinium chloride-containing nanoemulsion

    PubMed Central

    Lee, Valerie A.; Karthikeyan, Ramalingam; Rawls, H. Ralph; Amaechi, Bennett T.

    2010-01-01

    Objectives The aim of this pilot study was to investigate the anticaries activity of a nanoemulsion composed of soybean oil, water, Triton X-100 and cetylpyridinium chloride. Methods Tooth blocks (3 mm length × 3 mm width × 2 mm thickness) were cut from smooth surfaces of selected molar teeth using a water-cooled diamond wire saw. The blocks were randomly assigned to three experimental groups, (A) nanoemulsion, (B) 0.12% chlorhexidine gluconate, and (C) no treatment. The formation of dental caries in human tooth enamel was tested using a continuous flow dual-organism (Streptococcus mutans and Lactobacillus casei), biofilm model, which acts as an artificial mouth and simulates the biological and physiological activities observed within the oral environment. Experimental groups A and B were treated with their respective solutions once daily for 30 seconds on each occasion, while group C received no treatment. 10% sucrose was supplied every 6 hours for 6 minutes to simulate meals and pH cycling. The experiment lasted for 5 days, and the tooth blocks were harvested and processed for demineralization assessment using transverse microradiography (TMR). Results For both lesion depth and mineral loss, statistical analysis indicated that Emulsion was significantly lower than Control and Chlorhexidine, and Chlorhexidine was significantly lower than Control. Conclusions We conclude that cetylpyridinium-containing nanoemulsions appear to present a feasible means of preventing the occurrence of early caries. PMID:20600554

  10. Leiodermatolide, a novel marine natural product, has potent cytotoxic and antimitotic activity against cancer cells, appears to affect microtubule dynamics, and exhibits antitumor activity.

    PubMed

    Guzmán, Esther A; Xu, Qunli; Pitts, Tara P; Mitsuhashi, Kaoru Ogawa; Baker, Cheryl; Linley, Patricia A; Oestreicher, Judy; Tendyke, Karen; Winder, Priscilla L; Suh, Edward M; Wright, Amy E

    2016-11-01

    Pancreatic cancer, the fourth leading cause of cancer death in the United States, has a negative prognosis because metastasis occurs before symptoms manifest. Leiodermatolide, a polyketide macrolide with antimitotic activity isolated from a deep water sponge of the genus Leiodermatium, exhibits potent and selective cytotoxicity toward the pancreatic cancer cell lines AsPC-1, PANC-1, BxPC-3, and MIA PaCa-2, and potent cytotoxicity against skin, breast and colon cancer cell lines. Induction of apoptosis by leiodermatolide was confirmed in the AsPC-1, BxPC-3 and MIA PaCa-2 cells. Leiodermatolide induces cell cycle arrest but has no effects on in vitro polymerization or depolymerization of tubulin alone, while it enhances polymerization of tubulin containing microtubule associated proteins (MAPs). Observations through confocal microscopy show that leiodermatolide, at low concentrations, causes minimal effects on polymerization or depolymerization of the microtubule network in interphase cells, but disruption of spindle formation in mitotic cells. At higher concentrations, depolymerization of the microtubule network is observed. Visualization of the growing microtubule in HeLa cells expressing GFP-tagged plus end binding protein EB-1 showed that leiodermatolide stopped the polymerization of tubulin. These results suggest that leiodermatolide may affect tubulin dynamics without directly interacting with tubulin and hint at a unique mechanism of action. In a mouse model of metastatic pancreatic cancer, leiodermatolide exhibited significant tumor reduction when compared to gemcitabine and controls. The antitumor activities of leiodermatolide, as well as the proven utility of antimitotic compounds against cancer, make leiodermatolide an interesting compound with potential chemotherapeutic effects that may merit further research. PMID:27376928

  11. Leiodermatolide, a novel marine natural product, has potent cytotoxic and antimitotic activity against cancer cells, appears to affect microtubule dynamics, and exhibits antitumor activity.

    PubMed

    Guzmán, Esther A; Xu, Qunli; Pitts, Tara P; Mitsuhashi, Kaoru Ogawa; Baker, Cheryl; Linley, Patricia A; Oestreicher, Judy; Tendyke, Karen; Winder, Priscilla L; Suh, Edward M; Wright, Amy E

    2016-11-01

    Pancreatic cancer, the fourth leading cause of cancer death in the United States, has a negative prognosis because metastasis occurs before symptoms manifest. Leiodermatolide, a polyketide macrolide with antimitotic activity isolated from a deep water sponge of the genus Leiodermatium, exhibits potent and selective cytotoxicity toward the pancreatic cancer cell lines AsPC-1, PANC-1, BxPC-3, and MIA PaCa-2, and potent cytotoxicity against skin, breast and colon cancer cell lines. Induction of apoptosis by leiodermatolide was confirmed in the AsPC-1, BxPC-3 and MIA PaCa-2 cells. Leiodermatolide induces cell cycle arrest but has no effects on in vitro polymerization or depolymerization of tubulin alone, while it enhances polymerization of tubulin containing microtubule associated proteins (MAPs). Observations through confocal microscopy show that leiodermatolide, at low concentrations, causes minimal effects on polymerization or depolymerization of the microtubule network in interphase cells, but disruption of spindle formation in mitotic cells. At higher concentrations, depolymerization of the microtubule network is observed. Visualization of the growing microtubule in HeLa cells expressing GFP-tagged plus end binding protein EB-1 showed that leiodermatolide stopped the polymerization of tubulin. These results suggest that leiodermatolide may affect tubulin dynamics without directly interacting with tubulin and hint at a unique mechanism of action. In a mouse model of metastatic pancreatic cancer, leiodermatolide exhibited significant tumor reduction when compared to gemcitabine and controls. The antitumor activities of leiodermatolide, as well as the proven utility of antimitotic compounds against cancer, make leiodermatolide an interesting compound with potential chemotherapeutic effects that may merit further research.

  12. Structural definition of a potent macrophage activating factor derived from vitamin D3-binding protein with adjuvant activity for antibody production.

    PubMed

    Yamamoto, N

    1996-10-01

    Incubation of human vitamin D3-binding protein (Gc protein), with a mixture of immobilized beta-galactosidase and sialidase, efficiently generated a potent macrophage activating factor, a protein with N-acetylgalactosamine as the remaining sugar. Stepwise incubation of Gc protein with immobilized beta-galactosidase and sialidase, and isolation of the intermediates with immobilized lectins, revealed that either sequence of hydrolysis of Gc glycoprotein by these glycosidases yields the macrophage-activating factor, implying that Gc protein carries a trisaccharide composed of N-acetylgalactosamine and dibranched galactose and sialic acid termini. A 3 hr incubation of mouse peritoneal macrophages with picomolar amounts of the enzymatically generated macrophage-activating factor (GcMAF) resulted in a greatly enhanced phagocytic activity. Administration of a minute amount (10-50 pg/mouse) of GcMAF resulted in a seven- to nine-fold enhanced phagocytic activity of macrophages. Injection of sheep red blood cells (SRBC) along with GcMAF into mice produced a large number of anti-SRBC antibody secreting splenic cells in 2-4 days. PMID:9070663

  13. Discovery of a potent class I selective ketone histone deacetylase inhibitor with antitumor activity in vivo and optimized pharmacokinetic properties.

    PubMed

    Kinzel, Olaf; Llauger-Bufi, Laura; Pescatore, Giovanna; Rowley, Michael; Schultz-Fademrecht, Carsten; Monteagudo, Edith; Fonsi, Massimiliano; Gonzalez Paz, Odalys; Fiore, Fabrizio; Steinkühler, Christian; Jones, Philip

    2009-06-11

    The optimization of a potent, class I selective ketone HDAC inhibitor is shown. It possesses optimized pharmacokinetic properties in preclinical species, has a clean off-target profile, and is negative in a microbial mutagenicity (Ames) test. In a mouse xenograft model it shows efficacy comparable to that of vorinostat at a 10-fold reduced dose.

  14. 1-(Fluoroalkylidene)-1,1-bisphosphonic Acids are Potent and Selective Inhibitors of the Enzymatic Activity of Toxoplasma gondii Farnesyl Pyrophosphate Synthase

    PubMed Central

    Szajnman, Sergio H.; Rosso, Valeria S.; Malayil, Leena; Smith, Alyssa; Moreno, Silvia N. J.; Docampo, Roberto

    2012-01-01

    α-Fluorinated-1,1-bisphosphonic acids derived from fatty acids were designed, synthesized and biologically evaluated against Trypanosoma cruzi, the etiologic agent of Chagas disease and against Toxoplasma gondii, the responsible agent of toxoplasmosis and also towards the target parasitic enzymes farnesyl pyrophosphate synthase of T. cruzi (TcFPPS) and T gondii (TgFPPS), respectively. Interestingly, 1-fluorononylidene-1,1-bisphosphonic acid (compound 43) has proven to be an extremely potent inhibitor of the enzymatic activity of TgFPPS at the low nanomolar range exhibiting an IC50 of 30 nM. This compound was two-fold more potent than risedronate (IC50 = 74 nM) taken as a positive control. This enzymatic activity was associated to a strong cell growth inhibition against tachyzoites of T. gondii having an IC50 value of 2.7 μM. PMID:22215028

  15. Teotihuacanin, a Diterpene with an Unusual Spiro-10/6 System from Salvia amarissima with Potent Modulatory Activity of Multidrug Resistance in Cancer Cells.

    PubMed

    Bautista, Elihú; Fragoso-Serrano, Mabel; Toscano, Rubén A; García-Peña, María del Rosario; Ortega, Alfredo

    2015-07-01

    Teotihuacanin (1), an unusual rearranged clerodane diterpene with a new carbon skeleton containing a spiro-10/6 bicyclic system, was isolated from the leaves and flowers of Salvia amarissima. Its structure was determined through spectroscopic analyses. Its absolute configuration was established by single-crystal X-ray diffraction. Compound 1 showed potent modulatory activity of multidrug resistance in vinblastine-resistant MCF-7 cancer cell line (reversal fold, RFMCF-7/Vin+ > 10703) at 25 μg/mL.

  16. Activation of antigen-exposed iMC-DCs at the "right place" and "right time" promotes potent anti-tumor immunity.

    PubMed

    Spencer, David M

    2012-05-01

    To better control the "licensing" of pro-Th1 dendritic cells (DCs), Spencer and colleagues have developed a synthetic ligand-inducible chimeric receptor, iMyD88/CD40 (iMC), incorporating synergistic Toll-like receptor (TLR) and costimulatory signaling elements, permitting DC regulation in vivo within the context of an immunological synapse. This novel technology results in potent anti-cancer activity.

  17. Catechins and procyanidins of Ginkgo biloba show potent activities towards the inhibition of β-amyloid peptide aggregation and destabilization of preformed fibrils.

    PubMed

    Xie, Haiyan; Wang, Jing-Rong; Yau, Lee-Fong; Liu, Yong; Liu, Liang; Han, Quan-Bin; Zhao, Zhongzhen; Jiang, Zhi-Hong

    2014-04-22

    Catechins and procyanidins, together with flavonoid glycosides and terpene trilactones, are three important categories of components in the standard extract of Ginkgo biloba leaves (EGb761). In this research, catechins and proanthocyanidins were found to exist in both the extract of Ginkgo leaves and Ginkgo products. By comparing with reference compounds, six of them were identified as (+)-catechin, (-)-epicatechin, (-)-gallocatechin, (-)-epigallocatechin and procyanidins B1 and B3. The activities of these polyphenols in the inhibition of Aβ42 aggregation and the destabilization of preformed fibrils were evaluated using biochemical assays, which showed that all six of the polyphenols, as well as a fraction of the extract of Ginkgo biloba leaves (EGb) containing catechins and procyanidins, exerted potent inhibitory activities towards Aβ42 aggregation and could also destabilize the performed fibrils. Catechins and procyanidins can therefore be regarded as the potent active constituents of EGb761 in terms of their inhibition of Aβ42 aggregation and destabilization of the fibrils. Although quantitative mass spectroscopic analysis revealed that the catechins and procyanidins are only present in low concentrations in EGb761, these components should be studied in greater detail because of their potent inhibitory effects towards Aβ42 aggregation and their ability to destabilize preformed fibrils, especially during the quality control of Ginkgo leaves and the manufacture of Ginkgo products.

  18. 10-oxo-12(Z)-octadecenoic acid, a linoleic acid metabolite produced by gut lactic acid bacteria, potently activates PPARγ and stimulates adipogenesis

    SciTech Connect

    Goto, Tsuyoshi; Kim, Young-Il; Furuzono, Tomoya; Takahashi, Nobuyuki; Yamakuni, Kanae; Yang, Ha-Eun; Li, Yongjia; Ohue, Ryuji; Nomura, Wataru; Sugawara, Tatsuya; Yu, Rina; Kitamura, Nahoko; and others

    2015-04-17

    Our previous study has shown that gut lactic acid bacteria generate various kinds of fatty acids from polyunsaturated fatty acids such as linoleic acid (LA). In this study, we investigated the effects of LA and LA-derived fatty acids on the activation of peroxisome proliferator-activated receptors (PPARs) which regulate whole-body energy metabolism. None of the fatty acids activated PPARδ, whereas almost all activated PPARα in luciferase assays. Two fatty acids potently activated PPARγ, a master regulator of adipocyte differentiation, with 10-oxo-12(Z)-octadecenoic acid (KetoA) having the most potency. In 3T3-L1 cells, KetoA induced adipocyte differentiation via the activation of PPARγ, and increased adiponectin production and insulin-stimulated glucose uptake. These findings suggest that fatty acids, including KetoA, generated in gut by lactic acid bacteria may be involved in the regulation of host energy metabolism. - Highlights: • Most LA-derived fatty acids from gut lactic acid bacteria potently activated PPARα. • Among tested fatty acids, KetoA and KetoC significantly activated PPARγ. • KetoA induced adipocyte differentiation via the activation of PPARγ. • KetoA enhanced adiponectin production and glucose uptake during adipogenesis.

  19. Structure-guided design of aminopyrimidine amides as potent, selective inhibitors of lymphocyte specific kinase: synthesis, structure-activity relationships, and inhibition of in vivo T cell activation.

    PubMed

    DiMauro, Erin F; Newcomb, John; Nunes, Joseph J; Bemis, Jean E; Boucher, Christina; Chai, Lilly; Chaffee, Stuart C; Deak, Holly L; Epstein, Linda F; Faust, Ted; Gallant, Paul; Gore, Anu; Gu, Yan; Henkle, Brad; Hsieh, Faye; Huang, Xin; Kim, Joseph L; Lee, Josie H; Martin, Matthew W; McGowan, David C; Metz, Daniela; Mohn, Deanna; Morgenstern, Kurt A; Oliveira-dos-Santos, Antonio; Patel, Vinod F; Powers, David; Rose, Paul E; Schneider, Stephen; Tomlinson, Susan A; Tudor, Yan-Yan; Turci, Susan M; Welcher, Andrew A; Zhao, Huilin; Zhu, Li; Zhu, Xiaotian

    2008-03-27

    The lymphocyte-specific kinase (Lck), a member of the Src family of cytoplasmic tyrosine kinases, is expressed in T cells and natural killer (NK) cells. Genetic evidence, including knockout mice and human mutations, demonstrates that Lck kinase activity is critical for normal T cell development, activation, and signaling. Selective inhibition of Lck is expected to offer a new therapy for the treatment of T-cell-mediated autoimmune and inflammatory disease. With the aid of X-ray structure-based analysis, aminopyrimidine amides 2 and 3 were designed from aminoquinazolines 1, which had previously been demonstrated to exhibit potent inhibition of Lck and T cell proliferation. In this report, we describe the synthesis and structure-activity relationships of a series of novel aminopyrimidine amides 3 possessing improved cellular potency and selectivity profiles relative to their aminoquinazoline predecessors 1. Orally bioavailable compound 13b inhibited the anti-CD3-induced production of interleukin-2 (IL-2) in mice in a dose-dependent manner (ED 50 = 9.4 mg/kg). PMID:18321037

  20. Sj7170, a Unique Dual-function Peptide with a Specific α-Chymotrypsin Inhibitory Activity and a Potent Tumor-activating Effect from Scorpion Venom*

    PubMed Central

    Song, Yu; Gong, Ke; Yan, Hong; Hong, Wei; Wang, Le; Wu, Yingliang; Li, Wenhua; Li, Wenxin; Cao, Zhijian

    2014-01-01

    A new peptide precursor, termed Sj7170, was characterized from the venomous gland cDNA library of the scorpion Scorpiops jendeki. Sj7170 was deduced to be a 62-amino acid peptide cross-linked by five disulfide bridges. The recombinant Sj7170 peptide (rSj7170) with chromatographic purity was produced by a prokaryotic expression system. Enzyme inhibition assay in vitro and in vivo showed that rSj7170 specifically inhibited the activity of α-chymotrypsin at micromole concentrations. In addition, Sj7170 not only promoted cell proliferation and colony formation by up-regulating the expression of cyclin D1 in vitro but also enhanced tumor growth in nude mice. Finally, Sj7170 accelerated cellular migration and invasion by increasing the expression of the transcription factor Snail and then inducing the epithelial-mesenchymal transition. Moreover, Sj7170 changed cell morphology and cytoskeleton of U87 cells by the GTPase pathway. Taken together, Sj7170 is a unique dual-function peptide, i.e. a specific α-chymotrypsin inhibitor and a potent tumorigenesis/metastasis activator. Our work not only opens an avenue of developing new modulators of tumorigenesis/metastasis from serine protease inhibitors but also strengthens the functional link between protease inhibitors and tumor activators. PMID:24584937

  1. Significant decrease of ADP release rate underlies the potent activity of dimethylenastron to inhibit mitotic kinesin Eg5 and cancer cell proliferation

    SciTech Connect

    Sun, Linlin; Sun, Xiaodong; Xie, Songbo; Yu, Haiyang; Zhong, Diansheng

    2014-05-09

    Highlights: • DIMEN displays higher anti-proliferative activity than enastron. • DIMEN induced mitotic arrest and apoptosis more significantly than enastron. • DIMEN blocked the conformational change of ADP-binding pocket more effectively. • DIMEN hindered ADP release more potently than enastron. - Abstract: Eg5 is a mitotic kinesin that plays a crucial role in the formation of bipolar mitotic spindles, by hydrolyzing ATP to push apart anti-parallel microtubules. Dimethylenastron is potent specific small molecule inhibitor of Eg5. The mechanism by which dimethylenastron inhibits Eg5 function remains unclear. By comparing with enastron, here we report that dimethylenastron prevents the growth of pancreatic and lung cancer cells more effectively, by halting mitotic progression and triggering apoptosis. We analyze their interactions with ADP-bound Eg5 crystal structure, and find that dimethylenastron binds Eg5 motor domain with higher affinity. In addition, dimethylenastron allosterically blocks the conformational change of the “sandwich”-like ADP-binding pocket more effectively. We subsequently use biochemical approach to reveal that dimethylenastron slows ADP release more significantly than enastron. These data thus provide biological, structural and mechanistic insights into the potent inhibitory activity of dimethylenastron.

  2. Discovery of a tetracyclic quinoxaline derivative as a potent and orally active multifunctional drug candidate for the treatment of neuropsychiatric and neurological disorders.

    PubMed

    Li, Peng; Zhang, Qiang; Robichaud, Albert J; Lee, Taekyu; Tomesch, John; Yao, Wei; Beard, J David; Snyder, Gretchen L; Zhu, Hongwen; Peng, Youyi; Hendrick, Joseph P; Vanover, Kimberly E; Davis, Robert E; Mates, Sharon; Wennogle, Lawrence P

    2014-03-27

    We report the synthesis and structure-activity relationships of a class of tetracyclic butyrophenones that exhibit potent binding affinities to serotonin 5-HT(2A) and dopamine D2 receptors. This work has led to the discovery of 4-((6bR,10aS)-3-methyl-2,3,6b,9,10,10a-hexahydro-1H,7H-pyrido[3',4':4,5]pyrrolo[1,2,3-de]quinoxalin-8-yl)-1-(4-fluorophenyl)-butan-1-one 4-methylbenzenesulfonate (ITI-007), which is a potent 5-HT(2A) antagonist, postsynaptic D2 antagonist, and inhibitor of serotonin transporter. This multifunctional drug candidate is orally bioavailable and exhibits good antipsychotic efficacy in vivo. Currently, this investigational new drug is under clinical development for the treatment of neuropsychiatric and neurological disorders.

  3. Synthesis and structure-activity relationship of pyripyropene A derivatives as potent and selective acyl-CoA:cholesterol acyltransferase 2 (ACAT2) inhibitors: part 3.

    PubMed

    Ohtawa, Masaki; Yamazaki, Hiroyuki; Ohte, Satoshi; Matsuda, Daisuke; Ohshiro, Taichi; Rudel, Lawrence L; Ōmura, Satoshi; Tomoda, Hiroshi; Nagamitsu, Tohru

    2013-07-01

    In an effort to develop potent and selective inhibitors toward ACAT2, structure-activity relationship studies were carried out using derivatives based on pyripyropene A (PPPA, 1). In particular, we investigated the possibility of introducing appropriate 1,11-O-benzylidene and 7-O-substituted benzoyl moieties into PPPA (1). The new o-substituted benzylidene derivatives showed higher selectivity for ACAT2 than PPPA (1). Among them, 1,11-O-o-methylbenzylidene-7-O-p-cyanobenzoyl PPPA derivative 7q and 1,11-O-o,o-dimethylbenzylidene-7-O-p-cyanobenzoyl PPPA derivative 7z proved to be potent ACAT2 inhibitors with unprecedented high isozyme selectivity. PMID:23711919

  4. GD2-specific CAR T Cells Undergo Potent Activation and Deletion Following Antigen Encounter but can be Protected From Activation-induced Cell Death by PD-1 Blockade.

    PubMed

    Gargett, Tessa; Yu, Wenbo; Dotti, Gianpietro; Yvon, Eric S; Christo, Susan N; Hayball, John D; Lewis, Ian D; Brenner, Malcolm K; Brown, Michael P

    2016-06-01

    Chimeric antigen receptor (CAR) T cells have shown great promise in the treatment of hematologic malignancies but more variable results in the treatment of solid tumors and the persistence and expansion of CAR T cells within patients has been identified as a key correlate of antitumor efficacy. Lack of immunological "space", functional exhaustion, and deletion have all been proposed as mechanisms that hamper CAR T-cell persistence. Here we describe the events following activation of third-generation CAR T cells specific for GD2. CAR T cells had highly potent immediate effector functions without evidence of functional exhaustion in vitro, although reduced cytokine production reversible by PD-1 blockade was observed after longer-term culture. Significant activation-induced cell death (AICD) of CAR T cells was observed after repeated antigen stimulation, and PD-1 blockade enhanced both CAR T-cell survival and promoted killing of PD-L1(+) tumor cell lines. Finally, we assessed CAR T-cell persistence in patients enrolled in the CARPETS phase 1 clinical trial of GD2-specific CAR T cells in the treatment of metastatic melanoma. Together, these data suggest that deletion also occurs in vivo and that PD-1-targeted combination therapy approaches may be useful to augment CAR T-cell efficacy and persistence in patients.

  5. The Compound of Mangiferin-Berberine Salt Has Potent Activities in Modulating Lipid and Glucose Metabolisms in HepG2 Cells.

    PubMed

    Wang, Can; Jiang, Jian-Dong; Wu, Wei; Kong, Wei-Jia

    2016-01-01

    The mangiferin-berberine (MB) salt was synthesized by ionic bonding of mangiferin (M) and berberine (B) at an equal molecular ratio. This study aimed to investigate the activities of MB salt in modulating lipid and glucose metabolisms in HepG2 cells. After 24 h treatment of the studying compounds, cellular AMP-activated protein kinase α (AMPKα)/acetyl-CoA carboxylase (ACC) protein levels and carnitine palmitoyltransferase (CPT) 1 activities, intracellular lipid contents, mRNA expression levels of target genes, glucose consumption, and glucose production amounts were determined. Compound C (CC) was used in the blocking experiments. Our results showed that MB salt increased p-AMPKα (Thr172)/p-ACC (Ser79) levels and CPT1 activity and suppressed oleic acid- (OA-) induced lipid accumulation and upregulation of lipogenic genes potently in HepG2 cells. The above activities of MB salt were AMPK dependent and were superior to those of M or B when administered at an equal molar concentration. MB salt enhanced basal and insulin-stimulated glucose consumption and suppressed gluconeogenesis more potently than M or B alone. The inhibiting activity of MB salt on cellular gluconeogenesis was AMPK dependent. Our results may support MB salt as a new kind of agent for the development of novel lipid or glucose-lowering drugs in the future. PMID:27123455

  6. The Compound of Mangiferin-Berberine Salt Has Potent Activities in Modulating Lipid and Glucose Metabolisms in HepG2 Cells

    PubMed Central

    Wang, Can; Jiang, Jian-Dong; Wu, Wei; Kong, Wei-Jia

    2016-01-01

    The mangiferin-berberine (MB) salt was synthesized by ionic bonding of mangiferin (M) and berberine (B) at an equal molecular ratio. This study aimed to investigate the activities of MB salt in modulating lipid and glucose metabolisms in HepG2 cells. After 24 h treatment of the studying compounds, cellular AMP-activated protein kinase α (AMPKα)/acetyl-CoA carboxylase (ACC) protein levels and carnitine palmitoyltransferase (CPT) 1 activities, intracellular lipid contents, mRNA expression levels of target genes, glucose consumption, and glucose production amounts were determined. Compound C (CC) was used in the blocking experiments. Our results showed that MB salt increased p-AMPKα (Thr172)/p-ACC (Ser79) levels and CPT1 activity and suppressed oleic acid- (OA-) induced lipid accumulation and upregulation of lipogenic genes potently in HepG2 cells. The above activities of MB salt were AMPK dependent and were superior to those of M or B when administered at an equal molar concentration. MB salt enhanced basal and insulin-stimulated glucose consumption and suppressed gluconeogenesis more potently than M or B alone. The inhibiting activity of MB salt on cellular gluconeogenesis was AMPK dependent. Our results may support MB salt as a new kind of agent for the development of novel lipid or glucose-lowering drugs in the future. PMID:27123455

  7. Identification and Characterization of the First Cathelicidin from Sea Snakes with Potent Antimicrobial and Anti-inflammatory Activity and Special Mechanism.

    PubMed

    Wei, Lin; Gao, Jiuxiang; Zhang, Shumin; Wu, Sijin; Xie, Zeping; Ling, Guiying; Kuang, Yi-Qun; Yang, Yongliang; Yu, Haining; Wang, Yipeng

    2015-07-01

    Cathelicidins are a family of gene-encoded peptide effectors of innate immunity found exclusively in vertebrates. They play pivotal roles in host immune defense against microbial invasions. Dozens of cathelicidins have been identified from several vertebrate species. However, no cathelicidin from marine reptiles has been characterized previously. Here we report the identification and characterization of a novel cathelicidin (Hc-CATH) from the sea snake Hydrophis cyanocinctus. Hc-CATH is composed of 30 amino acids, and the sequence is KFFKRLLKSVRRAVKKFRKKPRLIGLSTLL. Circular dichroism spectroscopy and structure modeling analysis indicated that Hc-CATH mainly assumes an amphipathic α-helical conformation in bacterial membrane-mimetic solutions. It possesses potent broad-spectrum and rapid antimicrobial activity. Meanwhile, it is highly stable and shows low cytotoxicity toward mammalian cells. The microbial killing activity of Hc-CATH is executed through the disruption of cell membrane and lysis of bacterial cells. In addition, Hc-CATH exhibited potent anti-inflammatory activity by inhibiting the LPS-induced production of nitric oxide (NO) and pro-inflammatory cytokines such as TNF-α, IL-1β, and IL-6. Hc-CATH directly binds with LPS to neutralize its toxicity, and it also binds to Toll-like receptor 4 (TLR4/MD2 complex), which therefore inhibits the binding of LPS to TLR4/MD2 complex and the subsequent activation of LPS-induced inflammatory response pathways. Taken together, our study demonstrates that Hc-CATH, the first cathelicidin from sea snake discovered to have both antimicrobial and anti-inflammatory activity, is a potent candidate for the development of peptide antibiotics.

  8. Identification and Characterization of the First Cathelicidin from Sea Snakes with Potent Antimicrobial and Anti-inflammatory Activity and Special Mechanism*

    PubMed Central

    Wei, Lin; Gao, Jiuxiang; Zhang, Shumin; Wu, Sijin; Xie, Zeping; Ling, Guiying; Kuang, Yi-Qun; Yang, Yongliang; Yu, Haining; Wang, Yipeng

    2015-01-01

    Cathelicidins are a family of gene-encoded peptide effectors of innate immunity found exclusively in vertebrates. They play pivotal roles in host immune defense against microbial invasions. Dozens of cathelicidins have been identified from several vertebrate species. However, no cathelicidin from marine reptiles has been characterized previously. Here we report the identification and characterization of a novel cathelicidin (Hc-CATH) from the sea snake Hydrophis cyanocinctus. Hc-CATH is composed of 30 amino acids, and the sequence is KFFKRLLKSVRRAVKKFRKKPRLIGLSTLL. Circular dichroism spectroscopy and structure modeling analysis indicated that Hc-CATH mainly assumes an amphipathic α-helical conformation in bacterial membrane-mimetic solutions. It possesses potent broad-spectrum and rapid antimicrobial activity. Meanwhile, it is highly stable and shows low cytotoxicity toward mammalian cells. The microbial killing activity of Hc-CATH is executed through the disruption of cell membrane and lysis of bacterial cells. In addition, Hc-CATH exhibited potent anti-inflammatory activity by inhibiting the LPS-induced production of nitric oxide (NO) and pro-inflammatory cytokines such as TNF-α, IL-1β, and IL-6. Hc-CATH directly binds with LPS to neutralize its toxicity, and it also binds to Toll-like receptor 4 (TLR4/MD2 complex), which therefore inhibits the binding of LPS to TLR4/MD2 complex and the subsequent activation of LPS-induced inflammatory response pathways. Taken together, our study demonstrates that Hc-CATH, the first cathelicidin from sea snake discovered to have both antimicrobial and anti-inflammatory activity, is a potent candidate for the development of peptide antibiotics. PMID:26013823

  9. Bis-Arylidene Oxindole–Betulinic Acid Conjugate: A Fluorescent Cancer Cell Detector with Potent Anticancer Activity

    PubMed Central

    2015-01-01

    Molecules offering simultaneous detection and killing of cancer cells are advantageous. Hybrid of cancer cell-selective, ROS generator betulinic acid and bis-arylidene oxindole with amino propyl-linker is developed. With intrinsic fluorescence, the molecule exhibited cancer cell-specific residence. Further, it generated ROS, triggered apoptosis, and exhibited potent cytotoxicity in cancer cells selectively. We demonstrate the first example and use of isatins as betulinic acid conjugate for selective detection of cancer and subsequent killing of cancer cells via apoptosis. PMID:26005543

  10. Substituted N-aryl-6-pyrimidinones: A new class of potent, selective, and orally active p38 MAP kinase inhibitors

    SciTech Connect

    Devadas, Balekudru; Selness, Shaun R.; Xing, Li; Madsen, Heather M.; Marrufo, Laura D.; Shieh, Huey; Messing, Dean M.; Yang, Jerry Z.; Morgan, Heidi M.; Anderson, Gary D.; Webb, Elizabeth G.; Zhang, Jian; Devraj, Rajesh V.; Monahan, Joseph B.

    2012-02-28

    A novel series of highly potent and selective p38 MAP kinase inhibitors was developed originating from a substituted N-aryl-6-pyrimidinone scaffold. SAR studies coupled with in vivo evaluations in rat arthritis model culminated in the identification of 10 with excellent oral efficacy. Compound 10 exhibited a significantly enhanced dissolution rate compared to 1, translating to a high oral bioavailability (>90%) in rat. In animal studies 10 inhibited LPS-stimulated production of tumor necrosis factor-{alpha} in a dose-dependent manner and demonstrated robust efficacy comparable to dexamethasone in a rat streptococcal cell wall-induced arthritis model.

  11. Potent antitumor activities of recombinant human PDCD5 protein in combination with chemotherapy drugs in K562 cells

    SciTech Connect

    Shi, Lin; Song, Quansheng; Zhang, Yingmei; Lou, Yaxin; Wang, Yanfang; Tian, Linjie; Zheng, Yi; Ma, Dalong; Ke, Xiaoyan; Wang, Ying

    2010-05-28

    Conventional chemotherapy is still frequently used. Programmed cell death 5 (PDCD5) enhances apoptosis of various tumor cells triggered by certain stimuli and is lowly expressed in leukemic cells from chronic myelogenous leukemia patients. Here, we describe for the first time that recombinant human PDCD5 protein (rhPDCD5) in combination with chemotherapy drugs has potent antitumor effects on chronic myelogenous leukemia K562 cells in vitro and in vivo. The antitumor efficacy of rhPDCD5 protein with chemotherapy drugs, idarubicin (IDR) or cytarabine (Ara-C), was examined in K562 cells in vitro and K562 xenograft tumor models in vivo. rhPDCD5 protein markedly increased the apoptosis rates and decreased the colony-forming capability of K562 cells after the combined treatment with IDR or Ara-C. rhPDCD5 protein by intraperitoneal administration dramatically improved the antitumor effects of IDR treatment in the K562 xenograft model. The tumor sizes and cell proliferation were significantly decreased; and TUNEL positive cells were significantly increased in the combined group with rhPDCD5 protein and IDR treatment compared with single IDR treatment groups. rhPDCD5 protein, in combination with IDR, has potent antitumor effects on chronic myelogenous leukemia K562 cells and may be a novel and promising agent for the treatment of chronic myelogenous leukemia.

  12. Ethyl acetate extract from marine sponge Hyattella cribriformis exhibit potent anticancer activity by promoting tubulin polymerization as evidenced mitotic arrest and induction of apoptosis

    PubMed Central

    Annamalai, Pazhanimuthu; Thayman, Malini; Rajan, Sowmiya; Raman, Lakshmi Sundaram; Ramasubbu, Sankar; Perumal, Pachiappan

    2015-01-01

    Background: Marine sponges are important sources of bioactive compounds. Objective: This study investigated the anticancer properties of Hyattella cribriformis ethyl acetate (EA) fraction in various cancer and normal cell lines. Materials and Methods: anticancer assay was carried out in 15 cell lines to evaluate the anticancer potential of the EA fraction. Impact on cell cycle distribution was determined using flow cytometry. The fraction was investigated for interfering microtubules assembly in both in vitro and cellular assay. Further studies were conducted to determine the fraction induced cell death (apoptosis) using calcein/propidium iodide dual staining, activated caspase-3 and phosphorylation of Bcl-2 protein at Ser70. DNA fragmentation assay was performed to confirm the apoptosis. Results: EA fraction exhibited potent inhibition of cancer cell growth and resulted in 50% growth inhibition (GI50) of 0.27 μg/mL in A673 cell line. Sarcoma (MG-63, Saos-2) and ovarian (SK-OV-3 and OVCAR-3) cancer cell lines also showed superior anticancer activity GI50 of 1.0 μg/mL. Colon and breast cancer cell lines exhibited moderate GI compare other cancer cell lines and normal human lung fibroblast showed GI50 of 15.6 μg/mL. EA fraction showed potent G2/M phase arrest in A673 cell line and induced apoptosis at 48 h exposure. EA fraction promoted microtubule polymerization in tubulin polymerization assay and increased level of polymerized tubulin in the HeLa cells. Fraction induced the activation of caspase-3 and phosphorylation of Bcl-2 anti-apoptotic protein. Fraction induced DNA fragmentation in HeLa cells as evidence of apoptosis. Conclusion: Marine sponge H. cribriformis EA fraction exhibited potent anticancer activity through tubulin polymerization and induction of apoptosis. PMID:25829774

  13. Arctigenin, a phenylpropanoid dibenzylbutyrolactone lignan, inhibits MAP kinases and AP-1 activation via potent MKK inhibition: the role in TNF-alpha inhibition.

    PubMed

    Cho, Min Kyung; Jang, Young Pyo; Kim, Young Choong; Kim, Sang Geon

    2004-10-01

    Arctigenin, naturally occurring in Bardanae fructus, Saussurea medusa, Arctium lappa L., Torreya nucifera and Ipomea cairica, is a phenylpropanoid dibenzylbutyrolactone lignan with antioxidant and anti-inflammatory activities. Previously, we showed that arctigenin potently inhibited the induction of nitric oxide synthase (iNOS) by lipopolysaccharide (LPS), which involved suppression of NF-kappaB activation. In the present study, we examined the effects of arctigenin on mitogen-activated protein (MAP) kinase activation in Raw264.7 cells and MAP kinase kinase (MKK) activity. The effect of arctigenin on activator protein-1 (AP-1) activation was also studied in association with tumor necrosis factor-alpha (TNF-alpha) expression. Immunoblot analysis showed that arctigenin inhibited phosphorylation of MAP kinases ERK1/2, p38 kinase and JNK and their activities in Raw264.7 cells treated with LPS. Arctigenin potently inhibited the activity of MKK1 in vitro with the IC(50) value of 1 nM. Gel shift and reporter gene analyses revealed that arctigenin inhibited LPS-inducible AP-1 binding to the AP-1 consensus oligonucleotide and AP-1-mediated reporter gene expression. In view of the potential role of AP-1 in the induction of TNF-alpha, we next examined the inhibitory effects of arctigenin on the expression of TNF-alpha. Arctigenin blocked TNF-alpha production and decreased the level of TNF-alpha mRNA in the cells exposed to LPS. These results showed that arctigenin inhibited activation of MAP kinases including ERK1/2, p38 kinase and JNK through the inhibition of MKK activities, leading to AP-1 inactivation, which might, at least in part, contribute to the inhibition of TNF-alpha production.

  14. Identification of Potent, Selective P2Y-Purinoceptor Agonists: Structure–Activity Relationships for 2-Thioether Derivatives of Adenosine 5′-Triphosphate†

    PubMed Central

    Fischer, Bilha; Boyer, José L.; Hoyle, Charles H. V.; Ziganshin, Airat U.; Brizzolara, Antonia L.; Knight, Gillian E.; Zimmet, Jeffrey; Burnstock, Geoffrey; Harden, T. Kendall; Jacobson, Kenneth A.

    2012-01-01

    Study of P2-purinoceptor subtypes has been difficult due to the lack of potent and selective ligands. With the goal of developing high affinity P2-purinoceptor-selective agonists, we have synthesized a series of analogues of adenine nucleotides modified on the purine ring as chain-extended 2-thioethers or as N6-methyl-substituted compounds. Chemical functionality incorporated in the thioether moiety included cyanoalkyl, nitroaromatic, amino, thiol, cycloalkyl, n-alkyl, and olefinic groups. Apparent affinity of the compounds for P2Y-purinoceptors was established by measurement of P2Y-purinoceptor-promoted phospholipase C activity in turkey erythrocyte membranes and relaxation of carbachol-contracted smooth muscle in three different preparations (guinea pig taenia coil, rabbit aorta, and rabbit mesenteric artery). Activity at P2X-purinoceptors was established by measurement of contraction of rabbit saphenous artery and of the guinea pig vas deferens and urinary bladder. All 11 of the 2-thioethers of ATP stimulated the production of inositol phosphates with K0.5 values of 1.5–770 nM, with an (aminophenyl)ethyl derivative being most potent. Two adenosine diphosphate analogues were equipotent to the corresponding ATP analogues. Adenosine monophosphate analogues were full agonists, although generally 4 orders of magnitude less potent. ATP 2-thioethers displayed pD2 values in the range of 6–8 in smooth muscle assay systems for activity at P2Y-receptors. There was a significant correlation for the 2-thioether compounds between the pK0.5 values for inositol phosphate production and the pD2 values for relaxation mediated via the P2Y-purinoceptors in the guinea pig taenia coli, but not for the vascular P2Y-receptors or for the P2X-receptors. At P2X-receptors, no activity was observed in the rabbit saphenous artery, but variable degrees of activity were observed in the guinea pig vas deferens and bladder depending on distal substituents of the thioether moiety. N6-Methyl

  15. Novel potent and selective bile acid derivatives as TGR5 agonists: biological screening, structure-activity relationships, and molecular modeling studies.

    PubMed

    Sato, Hiroyuki; Macchiarulo, Antonio; Thomas, Charles; Gioiello, Antimo; Une, Mizuho; Hofmann, Alan F; Saladin, Régis; Schoonjans, Kristina; Pellicciari, Roberto; Auwerx, Johan

    2008-03-27

    TGR5, a metabotropic receptor that is G-protein-coupled to the induction of adenylate cyclase, has been recognized as the molecular link connecting bile acids to the control of energy and glucose homeostasis. With the aim of disclosing novel selective modulators of this receptor and at the same time clarifying the molecular basis of TGR5 activation, we report herein the biological screening of a collection of natural occurring bile acids, bile acid derivatives, and some steroid hormones, which has resulted in the discovery of new potent and selective TGR5 ligands. Biological results of the tested collection of compounds were used to extend the structure-activity relationships of TGR5 agonists and to develop a binary classification model of TGR5 activity. This model in particular could unveil some hidden properties shared by the molecular shape of bile acids and steroid hormones that are relevant to TGR5 activation and may hence be used to address the design of novel selective and potent TGR5 agonists.

  16. Potent activity of the lichen antibiotic (+)-usnic acid against clinical isolates of vancomycin-resistant enterococci and methicillin-resistant Staphylococcus aureus

    NASA Astrophysics Data System (ADS)

    Elo, Hannu; Matikainen, Jorma; Pelttari, Eila

    2007-06-01

    Vancomycin-resistant enterococci (VRE) and methicillin-resistant staphylococci, most notably methicillin-resistant Staphylococcus aureus (MRSA), are serious clinical problems. The antibiotic arsenal available against them is limited, and new mutants worsen the situation. We studied the activity of (+)-usnic acid, an old lichen-derived drug, and its sodium salt against clinical isolates of VRE and MRSA using the agar diffusion and minimal inhibitory concentration (MIC) methods. The acid and, especially, the sodium salt had potent antimicrobial activity against all clinical isolates of VRE and MRSA studied. The MIC values of the sodium salt against VRE strains ranged between 4 and 16 μg/ml (1-day test) and between 4 and 31 μg/ml (2-day test), being below 8 μg/ml for most strains. The salt had potent activity even against those strains that were not inhibited by ampicillin (125 μg/ml), and it never lost its activity after 24 h, in contrast to ampicillin. Thus, in spite of the fact that usnic acid can in some cases cause serious toxicity, it and its salts may be worth considering in clinical practice in cases where other therapies have failed or the microbe is resistant toward other agents.

  17. Cumulin, an Oocyte-secreted Heterodimer of the Transforming Growth Factor-β Family, Is a Potent Activator of Granulosa Cells and Improves Oocyte Quality.

    PubMed

    Mottershead, David G; Sugimura, Satoshi; Al-Musawi, Sara L; Li, Jing-Jie; Richani, Dulama; White, Melissa A; Martin, Georgia A; Trotta, Andrew P; Ritter, Lesley J; Shi, Junyan; Mueller, Thomas D; Harrison, Craig A; Gilchrist, Robert B

    2015-09-25

    Growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15) are oocyte-specific growth factors with central roles in mammalian reproduction, regulating species-specific fecundity, ovarian follicular somatic cell differentiation, and oocyte quality. In the human, GDF9 is produced in a latent form, the mechanism of activation being an open question. Here, we produced a range of recombinant GDF9 and BMP15 variants, examined their in silico and physical interactions and their effects on ovarian granulosa cells (GC) and oocytes. We found that the potent synergistic actions of GDF9 and BMP15 on GC can be attributed to the formation of a heterodimer, which we have termed cumulin. Structural modeling of cumulin revealed a dimerization interface identical to homodimeric GDF9 and BMP15, indicating likely formation of a stable complex. This was confirmed by generation of recombinant heterodimeric complexes of pro/mature domains (pro-cumulin) and covalent mature domains (cumulin). Both pro-cumulin and cumulin exhibited highly potent bioactivity on GC, activating both SMAD2/3 and SMAD1/5/8 signaling pathways and promoting proliferation and expression of a set of genes associated with oocyte-regulated GC differentiation. Cumulin was more potent than pro-cumulin, pro-GDF9, pro-BMP15, or the two combined on GC. However, on cumulus-oocyte complexes, pro-cumulin was more effective than all other growth factors at notably improving oocyte quality as assessed by subsequent day 7 embryo development. Our results support a model of activation for human GDF9 dependent on cumulin formation through heterodimerization with BMP15. Oocyte-secreted cumulin is likely to be a central regulator of fertility in mono-ovular mammals.

  18. Cumulin, an Oocyte-secreted Heterodimer of the Transforming Growth Factor-β Family, Is a Potent Activator of Granulosa Cells and Improves Oocyte Quality*

    PubMed Central

    Mottershead, David G.; Sugimura, Satoshi; Al-Musawi, Sara L.; Li, Jing-Jie; Richani, Dulama; White, Melissa A.; Martin, Georgia A.; Trotta, Andrew P.; Ritter, Lesley J.; Shi, Junyan; Mueller, Thomas D.; Harrison, Craig A.; Gilchrist, Robert B.

    2015-01-01

    Growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15) are oocyte-specific growth factors with central roles in mammalian reproduction, regulating species-specific fecundity, ovarian follicular somatic cell differentiation, and oocyte quality. In the human, GDF9 is produced in a latent form, the mechanism of activation being an open question. Here, we produced a range of recombinant GDF9 and BMP15 variants, examined their in silico and physical interactions and their effects on ovarian granulosa cells (GC) and oocytes. We found that the potent synergistic actions of GDF9 and BMP15 on GC can be attributed to the formation of a heterodimer, which we have termed cumulin. Structural modeling of cumulin revealed a dimerization interface identical to homodimeric GDF9 and BMP15, indicating likely formation of a stable complex. This was confirmed by generation of recombinant heterodimeric complexes of pro/mature domains (pro-cumulin) and covalent mature domains (cumulin). Both pro-cumulin and cumulin exhibited highly potent bioactivity on GC, activating both SMAD2/3 and SMAD1/5/8 signaling pathways and promoting proliferation and expression of a set of genes associated with oocyte-regulated GC differentiation. Cumulin was more potent than pro-cumulin, pro-GDF9, pro-BMP15, or the two combined on GC. However, on cumulus-oocyte complexes, pro-cumulin was more effective than all other growth factors at notably improving oocyte quality as assessed by subsequent day 7 embryo development. Our results support a model of activation for human GDF9 dependent on cumulin formation through heterodimerization with BMP15. Oocyte-secreted cumulin is likely to be a central regulator of fertility in mono-ovular mammals. PMID:26254468

  19. Tepoxalin: a dual cyclooxygenase/5-lipoxygenase inhibitor of arachidonic acid metabolism with potent anti-inflammatory activity and a favorable gastrointestinal profile.

    PubMed

    Argentieri, D C; Ritchie, D M; Ferro, M P; Kirchner, T; Wachter, M P; Anderson, D W; Rosenthale, M E; Capetola, R J

    1994-12-01

    Tepoxalin [5-(4-chlorophenyl)-N-hydroxy-(4-methoxyphenyl)-N-methyl-1H- pyrazole-3-propanamide] is a potent inhibitor of sheep seminal vesicle cyclooxygenase (CO) (IC50 = 4.6 microM), rat basophilic leukemia cell (RBL-1) lysate CO (IC50 = 2.85 microM) and CO from intact RBL-1 cells (IC50 = 4.2 microM). The compound inhibits the production of thromboxane B2 (TxB2) in Ca++ ionophore A-23187-stimulated human peripheral blood leukocytes (HPBL; IC50 = 0.01 microM) and human whole blood (IC50 = 0.08 microM) and is a potent inhibitor of epinephrine-induced human platelet aggregation (IC50 = 0.045 microM). Tepoxalin inhibits lipoxygenase (LO) in RBL-1 lysates (IC50 = 0.15 microM) and intact RBL-1 cells (IC50 = 1.7 microM) and inhibits the generation of leukotriene B4 (LTB4) in calcium ionophore A-23187-stimulated HPBL (IC50 = 0.07 microM) and human whole blood (IC50 = 1.57 microM). Human platelet 12-LO (IC50 = 3.0 microM) is inhibited, but 15-LO is only weakly so (IC50 = 157 microM). In vivo, tepoxalin, administered orally, demonstrated potent anti-inflammatory activity in the established adjuvant arthritic rat (ED50 = 3.5 mg/kg) and potent analgesic activity in the acetic acid abdominal construction assay in mice (ED50 = 0.45 mg/kg). In an ex vivo whole blood eicosanoid production assay, tepoxalin produces a dose-related inhibition of prostaglandin (PG) and LT production in dogs (PGF2 alpha - ED50 = 0.015 mg/kg; LTB4 - ED50 = 2.37 mg/kg) and adjuvant arthritic rats following oral administration. In adjuvant arthritic rats, tepoxalin is devoid of ulcerogenic activity within its anti-inflammatory therapeutic range (1-33 mg/kg p.o.) and does not exhibit ulcerogenic activity in normal rats at doses lower than 100 mg/kg (UD50 = 173 mg/kg p.o.). Tepoxalin represents a new class of anti-inflammatory drugs which may exhibit less gastrointestinal toxicity and may be efficacious in immunoinflammatory disease states where excessive PG and LT production has been implicated and may

  20. The latex sap of the 'Old World Plant' Lagenaria siceraria with potent lectin activity mitigates neoplastic malignancy targeting neovasculature and cell death.

    PubMed

    Vigneshwaran, V; Thirusangu, Prabhu; Madhusudana, S; Krishna, V; Pramod, Siddanakoppalu N; Prabhakar, B T

    2016-10-01

    Lifestyle and dietary modifications have contributed much to somatic genetic alteration which has concomitantly led to increase in malignant diseases. Henceforth, plant based and dietary interventions to mitigate and impede oncogenic transformation are in great demand. We investigated the latex sap (LSL) of the dietary Lagenaria siceraria vegetable, the first domesticated plant species with the potent lectin activity for its functional role against the tumor progression and its mechanism. LSL has markedly stimulated proliferation of lymphocytes and displayed strong cytotoxic activity against cancer both in-vitro and in-vivo. The tumor regression was paralleled with drastic reduction in tumoral neovasculature as evidenced from angiogenic parameters and abrogated related gene expressions. LSL has also triggered apoptotic signaling cascade in cancer cells through activation of caspase-3 mediated activation of endonuclease and inducing apoptotic cellular events. Collectively our study provides tangible evidences that latex sap from L. siceraria with immunopotentiating ability significantly regresses the tumor progression by targeting angiogenesis and inducing cell death.

  1. New betulinic acid derivatives induce potent and selective antiproliferative activity through cell cycle arrest at the S phase and caspase dependent apoptosis in human cancer cells.

    PubMed

    Santos, Rita C; Salvador, Jorge A R; Cortés, Roldán; Pachón, Gisela; Marín, Silvia; Cascante, Marta

    2011-06-01

    New semisynthetic derivatives of betulinic acid (BA) RS01, RS02 and RS03 with 18-45 times improved cytotoxic activity against HepG2 cells, were tested for their ability to induce apoptosis and cell cycle arrest in HepG2, HeLa and Jurkat cells. All the compounds induced significant increase in the population at the S phase more effectively than BA. RS01, RS02 and RS03 were also found to be potent inducers of apoptosis with RS01 being markedly more potent than BA, suggesting that the introduction of the imidazolyl moiety is crucial for enhancing the induction of apoptosis and the cell cycle arrest. The mechanism of apoptosis induction has been studied in HepG2 cells and found to be mediated by activation of the postmitochondrial caspases-9 and -3 cascade and possibly by mitochondrial amplification loop involving caspase-8. These facts were corroborated by detection of mitochondrial cytochrome c release and DNA fragmentation. Because RS01, RS02 and RS03 exhibited significant improved antitumor activity with respect to BA, they may be promising new agents for the treatment of cancer. In particular, RS01 is the most promising compound with an IC(50) value 45 times lower than BA on HepG2 cells and 61 times lower than the one found for the non-tumoral Chang liver cells.

  2. Novel triterpenoids isolated from raisins exert potent antiproliferative activities by targeting mitochondrial and Ras/Raf/ERK signaling in human breast cancer cells.

    PubMed

    Liu, Juan; Wang, Yihai; Liu, Rui Hai; He, Xiangjiu

    2016-07-13

    Raisins are produced in many regions of the world and may be eaten raw or used in cooking, baking and brewing. Bioactivity-guided fractionation of raisins was used to determine the chemical identity of bioactive constituents. Seven triterpenoids, including three novel triterpenoids, were isolated and identified. The novel triterpenoids were elucidated to be 3β,13β-dihydroxy-12,13-dihydrooleanolic acid (1), 3β,12β,13β-trihydroxy-12,13-dihydrooleanolic acid (2, TOA), and 3β,13β-dihydroxy-12,13-dihydroursolic acid (7), respectively. TOA showed the highest antiproliferative activity against MCF-7/DOX cells, with an EC50 value of 3.60 ± 0.55 μM. Compounds 1, 3 and 7 also exhibited potent antiproliferative activity against MCF-7/DOX cells, with an EC50 value of 7.10 ± 0.65, 10.22 ± 0.90 and 8.91 ± 1.12 μM. Compounds 1 and 2 also exhibited potent antioxidant activities. Moreover, the detailed cytotoxic mechanisms of TOA were investigated by targeting the mitochondrial and protein tyrosine kinase signaling (Ras/Raf/ERK). The results strongly demonstrated that the novel triterpenoids isolated from raisins could be promising candidates for therapy of breast cancer. PMID:27359376

  3. Synthesis and antibacterial evaluation of novel 4″-glycyl linked quinolyl-azithromycins with potent activity against macrolide-resistant pathogens.

    PubMed

    Pavlović, Dražen; Mutak, Stjepan

    2016-03-15

    A new azithromycin-based series of antibacterial macrolones is reported, which features the use of a 4″-ester linked glycin for tethering the quinolone side chain to the macrolide scaffold. Among the analogs prepared, compounds 9e and 22f with a quinolon-6-yl moiety were found to have potent and well-balanced activity against clinically important respiratory tract pathogens, including erythromycin-susceptible and MLSB resistant strains of Streptococcus pneumoniae, Streptococcus pyogenes, and Haemophilus influenzae. In addition, potential lead compounds 9e and 22f demonstrated outstanding levels of activity against Moraxella catarrhalis and inducibly MLSB resistant Staphylococcus aureus. The best member of this series 22f rivals or exceeds, in potency, some of the most active ketolide antibacterial agents known today, such as telithromycin and cethromycin. PMID:26860929

  4. Oblongifolin M, an active compound isolated from a Chinese medical herb Garcinia oblongifolia, potently inhibits enterovirus 71 reproduction through downregulation of ERp57

    PubMed Central

    Wang, Hua; He, Yaqing; Chen, Ying; Zhang, Hong; Wu, Rong; Chen, Xinchun; Zhou, Boping; He, Jason; Kung, Hsiang-Fu; Huang, Canhua; Wei, Yuquan; Huang, Jian-dong; Xu, Hongxi; He, Ming-Liang

    2016-01-01

    There is no effective drug to treat EV71 infection yet. Traditional Chinese herbs are great resources for novel antiviral compounds. Here we showed that Oblongifolin M (OM), an active compound isolated from Garcinia oblongifolia, potently inhibited EV71 infection in a dose dependent manner. To identify its potential effectors in the host cells, we successfully identified 18 proteins from 52 differentially expressed spots by comparative proteomics studies. Further studies showed that knockdown of ERp57 inhibited viral replication through downregulating viral IRES (internal ribosome entry site) activities, whereas ectopic expression of ERp57 increased IRES activity and partly rescued the inhibitory effects of OM on viral replication. We demonstrated that OM is an effective antiviral agent; and that ERp57 is one of its cellular effectors against EV71 infection. PMID:26848777

  5. Synthesis and antibacterial evaluation of novel 4″-glycyl linked quinolyl-azithromycins with potent activity against macrolide-resistant pathogens.

    PubMed

    Pavlović, Dražen; Mutak, Stjepan

    2016-03-15

    A new azithromycin-based series of antibacterial macrolones is reported, which features the use of a 4″-ester linked glycin for tethering the quinolone side chain to the macrolide scaffold. Among the analogs prepared, compounds 9e and 22f with a quinolon-6-yl moiety were found to have potent and well-balanced activity against clinically important respiratory tract pathogens, including erythromycin-susceptible and MLSB resistant strains of Streptococcus pneumoniae, Streptococcus pyogenes, and Haemophilus influenzae. In addition, potential lead compounds 9e and 22f demonstrated outstanding levels of activity against Moraxella catarrhalis and inducibly MLSB resistant Staphylococcus aureus. The best member of this series 22f rivals or exceeds, in potency, some of the most active ketolide antibacterial agents known today, such as telithromycin and cethromycin.

  6. Altertoxins with potent anti-HIV activity from Alternaria tenuissima QUE1Se, a fungal endophyte of Quercus emoryi.

    PubMed

    Bashyal, Bharat P; Wellensiek, Brian P; Ramakrishnan, Rajesh; Faeth, Stanley H; Ahmad, Nafees; Gunatilaka, A A Leslie

    2014-11-01

    Screening of a small library of natural product extracts derived from endophytic fungi of the Sonoran desert plants in a cell-based anti-HIV assay involving T-cells infected with the HIV-1 virus identified the EtOAc extract of a fermentation broth of Alternaria tenuissima QUE1Se inhabiting the stem tissue of Quercus emoryi as a promising candidate for further investigation. Bioactivity-guided fractionation of this extract led to the isolation and identification of two new metabolites, altertoxins V (1) and VI (2) together with the known compounds, altertoxins I (3), II (4), and III (5). The structures of 1 and 2 were determined by detailed spectroscopic analysis and those of 3-5 were established by comparison with reported data. When tested in our cell-based assay at concentrations insignificantly toxic to T-cells, altertoxins V (1), I (3), II (4), and III (5) completely inhibited replication of the HIV-1 virus at concentrations of 0.50, 2.20, 0.30, and 1.50 μM, respectively. Our findings suggest that the epoxyperylene structural scaffold in altertoxins may be manipulated to produce potent anti-HIV therapeutics.

  7. The oncolytic adenovirus Δ24-RGD in combination with cisplatin exerts a potent anti-osteosarcoma activity.

    PubMed

    Martinez-Velez, Naiara; Xipell, Enric; Jauregui, Patricia; Zalacain, Marta; Marrodan, Lucía; Zandueta, Carolina; Vera, Beatriz; Urquiza, Leire; Sierrasesúmaga, Luis; Julián, Mikel San; Toledo, Gemma; Fueyo, Juan; Gomez-Manzano, Candelaria; Torre, Wensceslao; Lecanda, Fernando; Patiño-García, Ana; Alonso, Marta M

    2014-10-01

    Osteosarcoma is the most common malignant bone tumor in children and adolescents. The presence of metastases and the lack of response to conventional treatment are the major adverse prognostic factors. Therefore, there is an urgent need for new treatment strategies that overcome both of these problems. Our purpose was to elucidate whether the use of the oncolytic adenovirus Δ24-RGD alone or in combination with standard chemotherapy would be effective, in vitro and in vivo, against osteosarcoma. Our results showed that Δ24-RGD exerted a potent antitumor effect against osteosarcoma cell lines that was increased by the addition of cisplatin. Δ24-RGD osteosarcoma treatment resulted in autophagy in vitro that was further enhanced when combined with cisplatin. Of importance, administration of Δ24-RGD and/or cisplatin, in novel orthotopic and two lung metastatic models in vivo resulted in a significant reduction of tumor burden meanwhile maintaining a safe toxicity profile. Together, our data underscore the potential of Δ24-RGD to become a realistic therapeutic option for primary and metastatic pediatric osteosarcoma. Moreover, this study warrants a future clinical trial to evaluate the safety and efficacy of Δ24-RGD for this devastating disease. PMID:24737304

  8. A Novel Laccase with Potent Antiproliferative and HIV-1 Reverse Transcriptase Inhibitory Activities from Mycelia of Mushroom Coprinus comatus

    PubMed Central

    Zhao, Shuang; Rong, Cheng-Bo; Kong, Chang; Liu, Yu; Xu, Feng; Miao, Qian-Jiang; Wang, Shou-Xian; Wang, He-Xiang

    2014-01-01

    A novel laccase was isolated and purified from fermentation mycelia of mushroom Coprinus comatus with an isolation procedure including three ion-exchange chromatography steps on DEAE-cellulose, CM-cellulose, and Q-Sepharose and one gel-filtration step by fast protein liquid chromatography on Superdex 75. The purified enzyme was a monomeric protein with a molecular weight of 64 kDa. It possessed a unique N-terminal amino acid sequence of AIGPVADLKV, which has considerably high sequence similarity with that of other fungal laccases, but is different from that of C. comatus laccases reported. The enzyme manifested an optimal pH value of 2.0 and an optimal temperature of 60°C using 2,2′-azinobis(3-ethylbenzothiazolone-6-sulfonic acid) diammonium salt (ABTS) as the substrate. The laccase displayed, at pH 2.0 and 37°C, Km values of 1.59 mM towards ABTS. It potently suppressed proliferation of tumor cell lines HepG2 and MCF7, and inhibited human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) with an IC50 value of 3.46 μM, 4.95 μM, and 5.85 μM, respectively, signifying that it is an antipathogenic protein. PMID:25540778

  9. Tetrahydro-2-naphthyl and 2-Indanyl Triazolopyrimidines Targeting Plasmodium falciparum Dihydroorotate Dehydrogenase Display Potent and Selective Antimalarial Activity

    PubMed Central

    2016-01-01

    Malaria persists as one of the most devastating global infectious diseases. The pyrimidine biosynthetic enzyme dihydroorotate dehydrogenase (DHODH) has been identified as a new malaria drug target, and a triazolopyrimidine-based DHODH inhibitor 1 (DSM265) is in clinical development. We sought to identify compounds with higher potency against Plasmodium DHODH while showing greater selectivity toward animal DHODHs. Herein we describe a series of novel triazolopyrimidines wherein the p-SF5-aniline was replaced with substituted 1,2,3,4-tetrahydro-2-naphthyl or 2-indanyl amines. These compounds showed strong species selectivity, and several highly potent tetrahydro-2-naphthyl derivatives were identified. Compounds with halogen substitutions displayed sustained plasma levels after oral dosing in rodents leading to efficacy in the P. falciparum SCID mouse malaria model. These data suggest that tetrahydro-2-naphthyl derivatives have the potential to be efficacious for the treatment of malaria, but due to higher metabolic clearance than 1, they most likely would need to be part of a multidose regimen. PMID:27127993

  10. Tetrahydro-2-naphthyl and 2-Indanyl Triazolopyrimidines Targeting Plasmodium falciparum Dihydroorotate Dehydrogenase Display Potent and Selective Antimalarial Activity.

    PubMed

    Kokkonda, Sreekanth; Deng, Xiaoyi; White, Karen L; Coteron, Jose M; Marco, Maria; de Las Heras, Laura; White, John; El Mazouni, Farah; Tomchick, Diana R; Manjalanagara, Krishne; Rudra, Kakali Rani; Chen, Gong; Morizzi, Julia; Ryan, Eileen; Kaminsky, Werner; Leroy, Didier; Martínez-Martínez, María Santos; Jimenez-Diaz, Maria Belen; Bazaga, Santiago Ferrer; Angulo-Barturen, Iñigo; Waterson, David; Burrows, Jeremy N; Matthews, Dave; Charman, Susan A; Phillips, Margaret A; Rathod, Pradipsinh K

    2016-06-01

    Malaria persists as one of the most devastating global infectious diseases. The pyrimidine biosynthetic enzyme dihydroorotate dehydrogenase (DHODH) has been identified as a new malaria drug target, and a triazolopyrimidine-based DHODH inhibitor 1 (DSM265) is in clinical development. We sought to identify compounds with higher potency against Plasmodium DHODH while showing greater selectivity toward animal DHODHs. Herein we describe a series of novel triazolopyrimidines wherein the p-SF5-aniline was replaced with substituted 1,2,3,4-tetrahydro-2-naphthyl or 2-indanyl amines. These compounds showed strong species selectivity, and several highly potent tetrahydro-2-naphthyl derivatives were identified. Compounds with halogen substitutions displayed sustained plasma levels after oral dosing in rodents leading to efficacy in the P. falciparum SCID mouse malaria model. These data suggest that tetrahydro-2-naphthyl derivatives have the potential to be efficacious for the treatment of malaria, but due to higher metabolic clearance than 1, they most likely would need to be part of a multidose regimen. PMID:27127993

  11. Analysis of the anti-apoptotic activity of four vaccinia virus proteins demonstrates that B13 is the most potent inhibitor in isolation and during viral infection

    PubMed Central

    Veyer, David L.; Maluquer de Motes, Carlos; Sumner, Rebecca P.; Ludwig, Louisa; Johnson, Benjamin F.

    2014-01-01

    Vaccinia virus (VACV) is a large dsDNA virus encoding ~200 proteins, several of which inhibit apoptosis. Here, a comparative study of anti-apoptotic proteins N1, F1, B13 and Golgi anti-apoptotic protein (GAAP) in isolation and during viral infection is presented. VACVs strains engineered to lack each gene separately still blocked apoptosis to some degree because of functional redundancy provided by the other anti-apoptotic proteins. To overcome this redundancy, we inserted each gene separately into a VACV strain (vv811) that lacked all these anti-apoptotic proteins and that induced apoptosis efficiently during infection. Each protein was also expressed in cells using lentivirus vectors. In isolation, each VACV protein showed anti-apoptotic activity in response to specific stimuli, as measured by immunoblotting for cleaved poly(ADP ribose) polymerase-1 and caspase-3 activation. Of the proteins tested, B13 was the most potent inhibitor, blocking both intrinsic and extrinsic stimuli, whilst the activity of the other proteins was largely restricted to inhibition of intrinsic stimuli. In addition, B13 and F1 were effective blockers of apoptosis induced by vv811 infection. Finally, whilst differences in induction of apoptosis were barely detectable during infection with VACV strain Western Reserve compared with derivative viruses lacking individual anti-apoptotic genes, several of these proteins reduced activation of caspase-3 during infection by vv811 strains expressing these proteins. These results illustrated that vv811 was a useful tool to determine the role of VACV proteins during infection and that whilst all of these proteins have some anti-apoptotic activity, B13 was the most potent. PMID:25090990

  12. Vialinin A and thelephantin G, potent inhibitors of tumor necrosis factor-α production, inhibit sentrin/SUMO-specific protease 1 enzymatic activity.

    PubMed

    Yoshioka, Yasukiyo; Namiki, Daisuke; Makiuchi, Mao; Sugaya, Kouichi; Onose, Jun-Ichi; Ashida, Hitoshi; Abe, Naoki

    2016-09-01

    Several p-terphenyl compounds have been isolated from the edible Chinese mushroom Thelephora vialis. Vialinin A, a p-terphenyl compound, strongly inhibits tumor necrosis factor-α production and release. Vialinin A inhibits the enzymatic activity of ubiquitin-specific peptidase 5, one of the target molecules in RBL-2H3 cells. Here we examined the inhibitory effect of p-terphenyl compounds, including vialinin A, against sentrin/SUMO-specific protease 1 (SENP1) enzymatic activity. The half maximal inhibitory concentration values of vialinin A and thelephantin G against full-length SENP1 were 1.64±0.23μM and 2.48±0.02μM, respectively. These findings suggest that p-terphenyl compounds are potent SENP1 inhibitors. PMID:27491710

  13. Fragment-based discovery of a new family of non-peptidic small-molecule cyclophilin inhibitors with potent antiviral activities

    PubMed Central

    Ahmed-Belkacem, Abdelhakim; Colliandre, Lionel; Ahnou, Nazim; Nevers, Quentin; Gelin, Muriel; Bessin, Yannick; Brillet, Rozenn; Cala, Olivier; Douguet, Dominique; Bourguet, William; Krimm, Isabelle; Pawlotsky, Jean-Michel; Guichou, Jean- François

    2016-01-01

    Cyclophilins are peptidyl-prolyl cis/trans isomerases (PPIase) that catalyse the interconversion of the peptide bond at proline residues. Several cyclophilins play a pivotal role in the life cycle of a number of viruses. The existing cyclophilin inhibitors, all derived from cyclosporine A or sanglifehrin A, have disadvantages, including their size, potential for side effects unrelated to cyclophilin inhibition and drug–drug interactions, unclear antiviral spectrum and manufacturing issues. Here we use a fragment-based drug discovery approach using nucleic magnetic resonance, X-ray crystallography and structure-based compound optimization to generate a new family of non-peptidic, small-molecule cyclophilin inhibitors with potent in vitro PPIase inhibitory activity and antiviral activity against hepatitis C virus, human immunodeficiency virus and coronaviruses. This family of compounds has the potential for broad-spectrum, high-barrier-to-resistance treatment of viral infections. PMID:27652979

  14. Potent immunosuppressive principles, dimeric sesquiterpene thioalkaloids, isolated from nupharis rhizoma, the rhizoma of Nuphar pumilum (nymphaeaceae): structure-requirement of nuphar-alkaloid for immunosuppressive activity.

    PubMed

    Yamahara, J; Shimoda, H; Matsuda, H; Yoshikawa, M

    1996-09-01

    Potent immunosuppressants, the dimeric sesquiterpene thioalkaloids, 6-hydroxythiobinupharidine (2), 6,6'-dihydroxythiobinupharidine (3), 6-hydroxythionuphlutine B (5) and 6'-hydroxythionuphlutine B (6), were isolated from a natural medicine, Nupharis Rhizoma, the rhizoma of Nuphar pumilum (TIMM.) DC., through bioassay-guided separation together with five quinolizidine alkaloids (8, 9, 10, 11, 12). Dimeric sesquiterpene thioalkaloids (2, 3, 5, 6) were found to significantly inhibit anti-sheep erythrocyte plaque forming cell formation in mice spleen cells at 10(-6) M concentration. At this concentration, 2, 5 and 6 were found to exhibit no cytotoxicity to mice spleen cells, and 3 also showed only a little cytotoxicity. In addition, the inhibitory activity of several Nuphar alkaloids, dimeric sesquiterpene thioalkaloids (1, 4, 7, 8), and monomeric sesquiterpene alkaloids (9, 10, 11, 12) on anti-sheep erythrocyte plaque forming cell formation was examined and some structural requirement of Nuphar alkaloid for immunosuppressive activity was determined.

  15. Anti-AIDS agents 87. New bio-isosteric dicamphanoyl-dihydropyranochromone (DCP) and dicamphanoyl-khellactone (DCK) analogues with potent anti-HIV activity.

    PubMed

    Liu, Hong-Shan; Xu, Shi-Qing; Cheng, Ming; Chen, Ying; Xia, Peng; Qian, Keduo; Xia, Yi; Yang, Zheng-Yu; Chen, Chin-Ho; Morris-Natschke, Susan L; Lee, Kuo-Hsiung

    2011-10-01

    Six 3'R,4'R-di-O-(S)-camphanoyl-2',2'-dimethyldihydropyrano[2,3-f]chromone (DCP) and two 3'R,4'R-di-O-(S)-camphanoyl-(+)-cis-khellactone (DCK) derivatives were designed, synthesized, and evaluated for inhibition of HIV-1(NL4-3) replication in TZM-bl cells. 2-Ethyl-2'-monomethyl-1'-oxa- and -1'-thia-DCP (5a, 6a), as well as 2-ethyl-1'-thia-DCP (7a) exhibited potent anti-HIV activity with EC(50) values of 30, 38 and 54 nM and therapeutic indexes of 152.6, 48.0 and 100.0, respectively, which were better than or comparable to those of the lead compound 2-ethyl-DCP in the same assay. 4-Methyl-1'-thia-DCK (8a) also showed significant inhibitory activity with an EC(50) of 128 nM and TI of 237.9.

  16. Potent and Selective Triazole-Based Inhibitors of the Hypoxia-Inducible Factor Prolyl-Hydroxylases with Activity in the Murine Brain

    PubMed Central

    Chan, Mun Chiang; Atasoylu, Onur; Hodson, Emma; Tumber, Anthony; Leung, Ivanhoe K. H.; Chowdhury, Rasheduzzaman; Gómez-Pérez, Verónica; Demetriades, Marina; Rydzik, Anna M.; Holt-Martyn, James; Tian, Ya-Min; Bishop, Tammie; Claridge, Timothy D. W.; Kawamura, Akane; Pugh, Christopher W.; Ratcliffe, Peter J.; Schofield, Christopher J.

    2015-01-01

    As part of the cellular adaptation to limiting oxygen availability in animals, the expression of a large set of genes is activated by the upregulation of the hypoxia-inducible transcription factors (HIFs). Therapeutic activation of the natural human hypoxic response can be achieved by the inhibition of the hypoxia sensors for the HIF system, i.e. the HIF prolyl-hydroxylases (PHDs). Here, we report studies on tricyclic triazole-containing compounds as potent and selective PHD inhibitors which compete with the 2-oxoglutarate co-substrate. One compound (IOX4) induces HIFα in cells and in wildtype mice with marked induction in the brain tissue, revealing that it is useful for studies aimed at validating the upregulation of HIF for treatment of cerebral diseases including stroke. PMID:26147748

  17. Mechanisms underlying the exquisite sensitivity of Candida albicans to combinatorial cationic and oxidative stress that enhances the potent fungicidal activity of phagocytes.

    PubMed

    Kaloriti, Despoina; Jacobsen, Mette; Yin, Zhikang; Patterson, Miranda; Tillmann, Anna; Smith, Deborah A; Cook, Emily; You, Tao; Grimm, Melissa J; Bohovych, Iryna; Grebogi, Celso; Segal, Brahm H; Gow, Neil A R; Haynes, Ken; Quinn, Janet; Brown, Alistair J P

    2014-01-01

    Immune cells exploit reactive oxygen species (ROS) and cationic fluxes to kill microbial pathogens, such as the fungus Candida albicans. Yet, C. albicans is resistant to these stresses in vitro. Therefore, what accounts for the potent antifungal activity of neutrophils? We show that simultaneous exposure to oxidative and cationic stresses is much more potent than the individual stresses themselves and that this combinatorial stress kills C. albicans synergistically in vitro. We also show that the high fungicidal activity of human neutrophils is dependent on the combinatorial effects of the oxidative burst and cationic fluxes, as their pharmacological attenuation with apocynin or glibenclamide reduced phagocytic potency to a similar extent. The mechanistic basis for the extreme potency of combinatorial cationic plus oxidative stress--a phenomenon we term stress pathway interference--lies with the inhibition of hydrogen peroxide detoxification by the cations. In C. albicans this causes the intracellular accumulation of ROS, the inhibition of Cap1 (a transcriptional activator that normally drives the transcriptional response to oxidative stress), and altered readouts of the stress-activated protein kinase Hog1. This leads to a loss of oxidative and cationic stress transcriptional outputs, a precipitous collapse in stress adaptation, and cell death. This stress pathway interference can be suppressed by ectopic catalase (Cat1) expression, which inhibits the intracellular accumulation of ROS and the synergistic killing of C. albicans cells by combinatorial cationic plus oxidative stress. Stress pathway interference represents a powerful fungicidal mechanism employed by the host that suggests novel approaches to potentiate antifungal therapy. Importance: The immune system combats infection via phagocytic cells that recognize and kill pathogenic microbes. Human neutrophils combat Candida infections by killing this fungus with a potent mix of chemicals that includes

  18. Investigational drug MLN0128, a novel TORC1/2 inhibitor, demonstrates potent oral antitumor activity in human breast cancer xenograft models.

    PubMed

    Gökmen-Polar, Yesim; Liu, Yi; Toroni, Rachel A; Sanders, Kerry L; Mehta, Rutika; Badve, Sunil; Rommel, Christian; Sledge, George W

    2012-12-01

    Aberrant activation of the mammalian target of rapamycin (mTOR) signaling plays an important role in breast cancer progression and represents a potential therapeutic target for breast cancer. In this study, we report the impact of the investigational drug MLN0128, a potent and selective small molecule active-site TORC1/2 kinase inhibitor, on tumor growth and metastasis using human breast cancer xenograft models. We assessed in vitro antiproliferative activity of MLN0128 in a panel of breast cancer cell lines. We next evaluated the impact of MLN0128 on tumor growth, angiogenesis and metastasis using mammary fat pad xenograft models of a non-VEGF (ML20) and a VEGF-driven (MV165) MCF-7 sublines harboring PIK3CA mutations. MLN0128 potently inhibited cell proliferation in various breast cancer cell lines harboring PIK3CA (IC(50): 1.5-53 nM), PTEN (IC(50): 1-149 nM), KRAS, and/or BRAF mutations (IC(50): 13-162 nM), and in human endothelial cells (IC(50): 33-40 nM) in vitro. In vivo, MLN0128 decreased primary tumor growth significantly in both non-VEGF (ML20; p = 0.05) and VEGF-driven MCF-7 (MV165; p = 0.014) xenograft models. MLN0128 decreased the phosphorylation of Akt, S6, 4E-BP1, and NDRG1 in both models. In contrast, rapamycin increased Akt activity and failed to reduce the phosphorylation of 4E-BP1, PRAS40, and NDRG1. VEGF-induced lung metastasis in MV165 is inhibited by MLN0128 and rapamycin. In conclusion, MLN0128 inhibits TORC1/2-dependent signaling in preclinical models of breast cancer. MLN0128 appears to be superior in blocking mTORC1/2 signaling in contrast to rapamycin. Our findings support the clinical research of MLN0128 in patients with breast cancer and metastasis.

  19. Taselisib (GDC-0032), a Potent β-Sparing Small Molecule Inhibitor of PI3K, Radiosensitizes Head and Neck Squamous Carcinomas Containing Activating PIK3CA Alterations

    PubMed Central

    Zumsteg, Zachary S.; Morse, Natasha; Krigsfeld, Gabriel; Gupta, Gaorav; Higginson, Daniel S.; Lee, Nancy Y.; Morris, Luc; Ganly, Ian; Shiao, Stephan L.; Powell, Simon N.; Chung, Christine H.; Scaltriti, Maurizio; Baselga, José

    2016-01-01

    Purpose Activating PIK3CA genomic alterations are frequent in head and neck squamous cell carcinoma (HNSCC), and there is an association between phosphoinositide 3-kinase (PI3K) signaling and radioresistance. Hence, we investigated the therapeutic efficacy of inhibiting PI3K with GDC-0032, a PI3K inhibitor with potent activity against p110α, in combination with radiation in HNSCC. Experimental Design The efficacy of GDC-0032 was assessed in vitro in 26 HNSCC cell lines with crystal violet proliferation assays, and changes in PI3K signaling were measured by Western blot analysis. Cytotoxicity and radiosensitization were assessed with Annexin V staining via flow cytometry and clonogenic survival assays, respectively. DNA damage repair was assessed with immunofluorescence for γH2AX foci, and cell cycle analysis was performed with flow cytometry. In vivo efficacy of GDC-0032 and radiation was assessed in xenografts implanted into nude mice. Results GDC-0032 inhibited potently PI3K signaling and displayed greater antiproliferative activity in HNSCC cell lines with PIK3CA mutations or amplification, whereas cell lines with PTEN alterations were relatively resistant to its effects. Pretreatment with GDC-0032 radiosensitized PIK3CA-mutant HNSCC cells, enhanced radiation-induced apoptosis, impaired DNA damage repair, and prolonged G2–M arrest following irradiation. Furthermore, combined GDC-0032 and radiation was more effective than either treatment alone in vivo in subcutaneous xenograft models. Conclusions GDC-0032 has increased potency in HNSCC cell lines harboring PIK3CA-activating aberrations. Further, combined GDC-0032 and radiotherapy was more efficacious than either treatment alone in PIK3CA-altered HNSCC in vitro and in vivo. This strategy warrants further clinical investigation PMID:26589432

  20. Eupafolin and Ethyl Acetate Fraction of Kalanchoe gracilis Stem Extract Show Potent Antiviral Activities against Enterovirus 71 and Coxsackievirus A16

    PubMed Central

    Wang, Ching-Ying; Huang, Shun-Chueh; Lai, Zhen-Rung; Ho, Yu-Ling; Jou, Yu-Jen; Kung, Szu-Hao; Zhang, Yongjun; Chang, Yuan-Shiun; Lin, Cheng-Wen

    2013-01-01

    Enterovirus 71 (EV71) and coxsackievirus A16 (CoxA16) are main pathogens of hand-foot-and-mouth disease, occasionally causing aseptic meningitis and encephalitis in tropical and subtropical regions. Kalanchoe gracilis, Da-Huan-Hun, is a Chinese folk medicine for treating pain and inflammation, exhibiting antioxidant and anti-inflammatory activities. Our prior report (2012) cited K. gracilis leaf extract as moderately active against EV71 and CoxA16. This study further rates antienteroviral potential of K. gracilis stem (KGS) extract to identify potent antiviral fractions and components. The extract moderately inhibits viral cytopathicity and virus yield, as well as in vitro replication of EV71 (IC50 = 75.18 μg/mL) and CoxA16 (IC50 = 81.41 μg/mL). Ethyl acetate (EA) fraction of KGS extract showed greater antiviral activity than that of n-butanol or aqueous fraction: IC50 values of 4.21 μg/mL against EV71 and 9.08 μg/mL against CoxA16. HPLC analysis, UV-Vis absorption spectroscopy, and plaque reduction assay indicate that eupafolin is a vital component of EA fraction showing potent activity against EV71 (IC50 = 1.39 μM) and CoxA16 (IC50 = 5.24 μM). Eupafolin specifically lessened virus-induced upregulation of IL-6 and RANTES by inhibiting virus-induced ERK1/2, AP-1, and STAT3 signals. Anti-enteroviral potency of KGS EA fraction and eupafolin shows the clinical potential against EV71 and CoxA16 infection. PMID:24078828

  1. Dual control mechanism for heme oxygenase: tin(IV)-protoporphyrin potently inhibits enzyme activity while markedly increasing content of enzyme protein in liver.

    PubMed Central

    Sardana, M K; Kappas, A

    1987-01-01

    Tin(IV)-protoporphyrin (Sn-protoporphyrin) potently inhibits heme degradation to bile pigments in vitro and in vivo, a property that confers upon this synthetic compound the ability to suppress a variety of experimentally induced and naturally occurring forms of jaundice in animals and humans. Utilizing rat liver heme oxygenase purified to homogeneity together with appropriate immunoquantitation techniques, we have demonstrated that Sn-protoporphyrin possesses the additional property of potently inducing the synthesis of heme oxygenase protein in liver cells while, concurrently, completely inhibiting the activity of the newly formed enzyme. Substitution of tin for the central iron atom of heme thus leads to the formation of a synthetic heme analogue that regulates heme oxygenase by a dual mechanism, which involves competitive inhibition of the enzyme for the natural substrate heme and simultaneous enhancement of new enzyme synthesis. Cobaltic(III)-protoporphyrin (Co-protoporphyrin) also inhibits heme oxygenase activity in vitro, but unlike Sn-protoporphyrin it greatly enhances the activity of the enzyme in the whole animal. Co-protoporphyrin also acts as an in vivo inhibitor of heme oxygenase; however, its inducing effect on heme oxygenase synthesis is so pronounced as to prevail in vivo over its inhibitory effect on the enzyme. These studies show that certain synthetic heme analogues possess the ability to simultaneously inhibit as well as induce the enzyme heme oxygenase in liver. The net balance between these two actions, as reflected in the rate of heme oxidation activity in the whole animal, appears to be influenced by the nature of the central metal atom of the synthetic metalloporphyrin. Images PMID:3470805

  2. A novel, selective inhibitor of fibroblast growth factor receptors that shows a potent broad spectrum of antitumor activity in several tumor xenograft models.

    PubMed

    Zhao, Genshi; Li, Wei-Ying; Chen, Daohong; Henry, James R; Li, Hong-Yu; Chen, Zhaogen; Zia-Ebrahimi, Mohammad; Bloem, Laura; Zhai, Yan; Huss, Karen; Peng, Sheng-Bin; McCann, Denis J

    2011-11-01

    The fibroblast growth factor receptors (FGFR) are tyrosine kinases that are present in many types of endothelial and tumor cells and play an important role in tumor cell growth, survival, and migration as well as in maintaining tumor angiogenesis. Overexpression of FGFRs or aberrant regulation of their activities has been implicated in many forms of human malignancies. Therefore, targeting FGFRs represents an attractive strategy for development of cancer treatment options by simultaneously inhibiting tumor cell growth, survival, and migration as well as tumor angiogenesis. Here, we describe a potent, selective, small-molecule FGFR inhibitor, (R)-(E)-2-(4-(2-(5-(1-(3,5-Dichloropyridin-4-yl)ethoxy)-1H-indazol-3yl)vinyl)-1H-pyrazol-1-yl)ethanol, designated as LY2874455. This molecule is active against all 4 FGFRs, with a similar potency in biochemical assays. It exhibits a potent activity against FGF/FGFR-mediated signaling in several cancer cell lines and shows an excellent broad spectrum of antitumor activity in several tumor xenograft models representing the major FGF/FGFR relevant tumor histologies including lung, gastric, and bladder cancers and multiple myeloma, and with a well-defined pharmacokinetic/pharmacodynamic relationship. LY2874455 also exhibits a 6- to 9-fold in vitro and in vivo selectivity on inhibition of FGF- over VEGF-mediated target signaling in mice. Furthermore, LY2874455 did not show VEGF receptor 2-mediated toxicities such as hypertension at efficacious doses. Currently, this molecule is being evaluated for its potential use in the clinic.

  3. Romidepsin (FK228) and its analogs directly inhibit phosphatidylinositol 3-kinase activity and potently induce apoptosis as histone deacetylase/phosphatidylinositol 3-kinase dual inhibitors.

    PubMed

    Saijo, Ken; Katoh, Tadashi; Shimodaira, Hideki; Oda, Akifumi; Takahashi, Ohgi; Ishioka, Chikashi

    2012-11-01

    Activation of phosphatidylinositol 3-kinase (PI3K) signaling is involved in carcinogenesis and cancer progression. The PI3K inhibitors are considered candidate drugs for cancer treatment. Here, we describe a drug screening system for novel PI3K inhibitors using Saccharomyces cerevisiae strains with deleterious mutations in the ATP-binding cassette transporter genes, because wild-type S. cerevisiae uses drug efflux pumps for reducing intracellular drug concentrations. By screening the chemical library of the Screening Committee of Anticancer Drugs, we identified the histone deacetylase (HDAC) inhibitor romidepsin (FK228) and its novel analogs. In vitro PI3K activity assays confirmed that these compounds directly inhibit PI3K activity at μM-range concentrations. FK-A5 analog was the most potent inhibitor. Western blotting revealed that these compounds inhibit phosphorylation of protein kinase B and downstream signaling components. Molecular modeling of the PI3K-FK228 complex indicated that FK228 binds to the ATP-binding pocket of PI3K. At μM-range concentrations, FK228 and FK-A5 show potent cytotoxicity, inducing apoptosis even in HDAC inhibitor-resistant cells. Furthermore, HDAC/PI3K dual inhibition by FK228 and FK-A5 at μM-range concentrations potentiates the apoptosis induction, mimicking the effect of combining specific HDAC and PI3K inhibitors. In this study, we showed that FK228 and its analogs directly inhibit PI3K activity and induce apoptosis at μM-range concentrations, similar to HDAC/PI3K dual inhibition. In future, optimizing the potency of FK228 and its analogs against PI3K may contribute to the development of novel HDAC/PI3K dual inhibitors for cancer treatment.

  4. Potent Natural Soluble Epoxide Hydrolase Inhibitors from Pentadiplandra brazzeana Baillon: Synthesis, Quantification, and Measurement of Biological Activities In Vitro and In Vivo

    PubMed Central

    Kitamura, Seiya; Morisseau, Christophe; Inceoglu, Bora; Kamita, Shizuo G.; De Nicola, Gina R.; Nyegue, Maximilienne; Hammock, Bruce D.

    2015-01-01

    We describe here three urea-based soluble epoxide hydrolase (sEH) inhibitors from the root of the plant Pentadiplandra brazzeana. The concentration of these ureas in the root was quantified by LC-MS/MS, showing that 1, 3-bis (4-methoxybenzyl) urea (MMU) is the most abundant (42.3 μg/g dry root weight). All of the ureas were chemically synthesized, and their inhibitory activity toward recombinant human and recombinant rat sEH was measured. The most potent compound, MMU, showed an IC50 of 92 nM via fluorescent assay and a Ki of 54 nM via radioactivity-based assay on human sEH. MMU effectively reduced inflammatory pain in a rat nociceptive pain assay. These compounds are among the most potent sEH inhibitors derived from natural sources. Moreover, inhibition of sEH by these compounds may mechanistically explain some of the therapeutic effects of P. brazzeana. PMID:25659109

  5. Effects of 14-methoxymetopon, a potent opioid agonist, on the responses to the tail electric stimulation test and plus-maze activity in male rats: neuroendocrine correlates.

    PubMed

    Urigüen, Leyre; Fernández, Beatriz; Romero, Eva Maria; De Pedro, Nuria; Delgado, Maria Jesús; Guaza, Carmen; Schmidhammer, Helmut; Viveros, Maria Paz

    2002-03-15

    We have studied the effects of 14-methoxymetopon (HS 198), a potent opioid agonist, on the responses to the tail electric stimulation test and plus-maze activity of adult male rats. The prototype mu agonist morphine was used as the drug of reference. Besides we addressed the effects of HS 198 on the serum corticosterone levels and on serotonergic systems of discrete brain regions. Both drugs were administered subcutaneously. Morphine (5 mg/kg) and HS 198 (30 microg/kg) induced a similar effect on the nociceptive test, with both drugs significantly increasing the threshold for the vocalization afterdischarge, which is related to the emotional component of pain. In the plus-maze, morphine (5 mg/kg) and HS 198 (20 and 30 microg/kg) induced similar increases in the percentages of entries and time in the open arms, two parameters related to the anxiety state of the animals. The results indicate that HS 198 is far more potent than morphine in reducing the emotive/affective component of pain and in inducing an anxiolytic effect. HS 198 (30 microg/kg) also induced parallel increases in the serum corticosterone levels and the hypothalamic serotonin content. A possible correlation between the anxiolytic action of the drug and its effect on the hypothalamic serotonergic system is suggested.

  6. Potent antitumor 9-anilinoacridines and acridines bearing an alkylating N-mustard residue on the acridine chromophore: synthesis and biological activity.

    PubMed

    Su, Tsann-Long; Lin, Yi-Wen; Chou, Ting-Chao; Zhang, Xiuguo; Bacherikov, Valeriy A; Chen, Ching-Huang; Liu, Leroy F; Tsai, Tsong-Jen

    2006-06-15

    A series of 9-anilinoacridine and acridine derivatives bearing an alkylating N-mustard residue at C4 of the acridine chromophore were synthesized. The N-mustard pharmacophore was linked to the C4 of the acridine ring with an O-ethyl (O-C(2)), O-propyl (O-C(3)), or O-butyl (O-C(4)) spacer. It revealed that all newly synthesized compounds were very potent cytotoxic agents against human leukemia and various solid tumors in vitro. These agents did not exhibit cross-resistance against vinblastine-resistant (CCRF-CEM/VBL) or taxol-resistant (CCRF-CEM/taxol) cells. It also showed that these agents were DNA cross-linking agents rather than topoisomerase II inhibitors. Of these agents, compounds 27a and 27c were shown to have potent antitumor activity in nude mice bearing the human breast carcinoma MX-1 xenograft. The therapeutic efficacies of these two agents are comparable to that of taxol.

  7. 2-Alkynyl derivatives of adenosine-5'-N-ethyluronamide: selective A2 adenosine receptor agonists with potent inhibitory activity on platelet aggregation.

    PubMed

    Cristalli, G; Volpini, R; Vittori, S; Camaioni, E; Monopoli, A; Conti, A; Dionisotti, S; Zocchi, C; Ongini, E

    1994-05-27

    A series of new 2-alkynyl and 2-cycloalkynyl derivatives of adenosine-5'-N-ethyluronamide (NECA) and of N-ethyl-1'-deoxy-1'-(6-amino-2-hexynyl-9H-purin-9-yl)-beta-D- ribofuranuronamide (1, HE-NECA), bearing hydroxy, amino, chloro, and cyano groups in the side chain, were synthesized. The compounds were studied in binding and functional assays to assess their potency for the A2 compared to A1 adenosine receptor. The presence of an alpha-hydroxyl group in the alkynyl chain of NECA derivatives accounts for the A2 agonist potency, leading to compounds endowed with sub-nanomolar affinity in binding studies. However, these analogues also possess good A1 receptor affinity resulting in low A2 selectivity. From functional experiments the 4-hydroxy-1-butynyl (6) and the 4-(2-tetrahydro-2H-pyranyloxy)-1-butynyl (16) derivatives appear to be very potent in inducing vasorelaxation without appreciable effect on heart rate. The new compounds were also tested as inhibitors of platelet aggregation induced by ADP. Introduction of an alpha-hydroxyl group in the alkynyl side chain caused a greater increase in antiaggregatory activity than either NECA or HE-NECA, resulting in the most potent inhibitors of platelet aggregation so far known in the nucleoside series. The presence of an alpha-quaternary carbon such as the 3-hydroxy-3,5-dimethyl-1-hexynyl (12) and the 3-hydroxy-3-phenyl-1-butynyl (15) derivatives markedly reduced the antiaggregatory potency without affecting the A2 affinity. The hydrophobicity index (k') of the new nucleosides barely correlated with the binding data, whereas high k' values were associated with increased A2 vs A1 selectivity but with reduced activity in all functional assays. Some of the compounds synthesized possess interesting pharmacological properties. Compounds having an appropriate balance between vasorelaxation and antiplatelet activity, if confirmed in vivo, deserve further development for the treatments of cardiovascular disorders.

  8. Candida albicans isolates from a Malaysian hospital exhibit more potent phospholipase and haemolysin activities than non-albicans Candida isolates.

    PubMed

    Chin, V K; Foong, K J; Maha, A; Rusliza, B; Norhafizah, M; Ng, K P; Chong, P P

    2013-12-01

    This study was aimed at determining the phospholipase and haemolysin activity of Candida isolates in Malaysia. A total of 37 Candida clinical isolates representing seven species, Candida albicans (12), Candida tropicalis (8), Candida glabrata (4), Candida parapsilosis (1), Candida krusei (4), Candida orthopsilosis (1) and Candida rugosa (7) were tested. In vitro phospholipase activity was determined by using egg yolk plate assay whereas in vitro haemolysin activity was tested by using blood plate assay on sheep blood Sabouraud's dextrose agar (SDA) enriched with glucose. Phospholipase activity was detected in 75% (9 out of 12) of the C. albicans isolates. Among the 25 non- C. albicans Candida isolates, phospholipase activity was detected in only 24% of these isolates. The phospholipase activity of C. albicans was significantly higher than that of the non- C. albicans Candida isolates (P=0.002). Haemolysin activity was detected in 100% of the C. albicans, C. tropicalis, C. glabrata, C. krusei, C. parapsilosis, and C. orthopsilosis isolates while 75% of the C. krusei isolates and 12.3% of the C. rugosa isolates showed haemolysin activity. The haemolytic activity of C. albicans was significantly higher than that of the non- C. albicans Candida isolates (P=0.0001).The findings in this study indicate that C. albicans isolates in Malaysia may possess greater virulence potential than the non-albicans species.

  9. Synthesis and potent antiprotozoal activity of mono/di amidino 2-anilinobenzimidazoles versus Plasmodium falciparum and Trypanosoma brucei rhodesiense.

    PubMed

    Karaaslan, Cigdem; Kaiser, Marcel; Brun, Reto; Göker, Hakan

    2016-09-15

    A series of mono and dicationic new 2-anilinobenzimidazole carboxamidines were prepared in a four step process starting from 4-amino-3-nitrobenzonitrile and corresponding o-phenylenediamines. Their antiparasitic activity against Plasmodium falciparum (P. falciparum) and Trypanosoma brucei rhodesiense (T.b. rhodesiense) were evaluated in vitro. Some of the dicationic compounds (10,12,14) showed equal or very close activity against T.b. rhodesiense with melarsoprol and also showed promising activity against P. falciparum as compared to chloroquine. Among the monocationic derivatives compound 21 exhibited best inhibitory activity against P. falciparum. PMID:27387356

  10. The Antipancreatic Cancer Activity of OSI-027, a Potent and Selective Inhibitor of mTORC1 and mTORC2

    PubMed Central

    Chen, Bo; Xu, Ming; Zhang, Hui; Xu, Ming-zheng; Wang, Xu-jing; Tang, Qing-he

    2015-01-01

    In the present study, we investigated the potential activity of OSI-027, a potent and selective mammalian target of rapamycin (mTOR) complex 1/2 (mTORC1/2) dual inhibitor, against pancreatic cancer cells both in vitro and in vivo. We demonstrated that OSI-027 inhibited survival and growth of both primary and transformed (PANC-1 and MIA PaCa-2 lines) human pancreatic cancer cells. Meanwhile, OSI-027 induced caspase-dependent apoptotic death of the pancreatic cancer cells. On the other hand, caspase inhibitors alleviated cytotoxicity by OSI-027. At the molecular level, OSI-027 treatment blocked mTORC1 and mTORC2 activation simultaneously, without affecting ERK–mitogen-activated protein kinase activation. Importantly, OSI-027 activated cytoprotective autophagy in the above cancer cells. Whereas pharmacological blockage of autophagy or siRNA knockdown of Beclin-1 significantly enhanced the OSI-027-induced activity against pancreatic cancer cells. Specifically, a relatively low dose of OSI-027 sensitized gemcitabine-induced pancreatic cancer cell death in vitro. Further, administration of OSI-027 or together with gemcitabine dramatically inhibited PANC-1 xenograft growth in severe combined immunodeficiency mice, leading to significant mice survival improvement. In summary, the preclinical results of this study suggest that targeting mTORC1/2 synchronously by OSI-027 could be further investigated as a valuable treatment for pancreatic cancer. PMID:26284306

  11. The Antipancreatic Cancer Activity of OSI-027, a Potent and Selective Inhibitor of mTORC1 and mTORC2.

    PubMed

    Chen, Bo; Xu, Ming; Zhang, Hui; Xu, Ming-zheng; Wang, Xu-jing; Tang, Qing-he; Tang, Jian-ying

    2015-10-01

    In the present study, we investigated the potential activity of OSI-027, a potent and selective mammalian target of rapamycin (mTOR) complex 1/2 (mTORC1/2) dual inhibitor, against pancreatic cancer cells both in vitro and in vivo. We demonstrated that OSI-027 inhibited survival and growth of both primary and transformed (PANC-1 and MIA PaCa-2 lines) human pancreatic cancer cells. Meanwhile, OSI-027 induced caspase-dependent apoptotic death of the pancreatic cancer cells. On the other hand, caspase inhibitors alleviated cytotoxicity by OSI-027. At the molecular level, OSI-027 treatment blocked mTORC1 and mTORC2 activation simultaneously, without affecting ERK-mitogen-activated protein kinase activation. Importantly, OSI-027 activated cytoprotective autophagy in the above cancer cells. Whereas pharmacological blockage of autophagy or siRNA knockdown of Beclin-1 significantly enhanced the OSI-027-induced activity against pancreatic cancer cells. Specifically, a relatively low dose of OSI-027 sensitized gemcitabine-induced pancreatic cancer cell death in vitro. Further, administration of OSI-027 or together with gemcitabine dramatically inhibited PANC-1 xenograft growth in severe combined immunodeficiency mice, leading to significant mice survival improvement. In summary, the preclinical results of this study suggest that targeting mTORC1/2 synchronously by OSI-027 could be further investigated as a valuable treatment for pancreatic cancer. PMID:26284306

  12. Synthesis of potent and broad genotypically active NS5B HCV non-nucleoside inhibitors binding to the thumb domain allosteric site 2 of the viral polymerase.

    PubMed

    Pierra Rouvière, Claire; Amador, Agnès; Badaroux, Eric; Convard, Thierry; Da Costa, Daniel; Dukhan, David; Griffe, Ludovic; Griffon, Jean-François; LaColla, Massimiliano; Leroy, Frédéric; Liuzzi, Michel; Loi, Anna Giulia; McCarville, Joe; Mascia, Valeria; Milhau, Julien; Onidi, Loredana; Paparin, Jean-Laurent; Rahali, Rachid; Sais, Efisio; Seifer, Maria; Surleraux, Dominique; Standring, David; Dousson, Cyril

    2016-09-15

    The hepatitis C virus (HCV) NS5B RNA-dependent RNA polymerase (RdRp) plays a central role in virus replication. NS5B has no functional equivalent in mammalian cells and, as a consequence, is an attractive target for selective inhibition. This Letter describes the discovery of a new family of HCV NS5B non-nucleoside inhibitors, based on the bioisosterism between amide and phosphonamidate functions. As part of this program, SAR in this new series led to the identification of IDX17119, a potent non-nucleoside inhibitor, active on the genotypes 1b, 2a, 3a and 4a. The structure and binding domain of IDX17119 were confirmed by X-ray co-crystallization study. PMID:27520942

  13. A Newly Emerged Swine-Origin Influenza A(H3N2) Variant Dampens Host Antiviral Immunity but Induces Potent Inflammasome Activation.

    PubMed

    Cao, Weiping; Mishina, Margarita; Ranjan, Priya; De La Cruz, Juan A; Kim, Jin Hyang; Garten, Rebecca; Kumar, Amrita; García-Sastre, Adolfo; Katz, Jacqueline M; Gangappa, Shivaprakash; Sambhara, Suryaprakash

    2015-12-15

    We compared the innate immune response to a newly emerged swine-origin influenza A(H3N2) variant containing the M gene from 2009 pandemic influenza A(H1N1), termed "A(H3N2)vpM," to the immune responses to the 2010 swine-origin influenza A(H3N2) variant and seasonal influenza A(H3N2). Our results demonstrated that A(H3N2)vpM-induced myeloid dendritic cells secreted significantly lower levels of type I interferon (IFN) but produced significantly higher levels of proinflammatory cytokines and induced potent inflammasome activation. The reduction in antiviral immunity with increased inflammatory responses upon A(H3N2)vpM infection suggest that these viruses have the potential for increased disease severity in susceptible hosts. PMID:26068782

  14. The Curcumin Analog C-150, Influencing NF-κB, UPR and Akt/Notch Pathways Has Potent Anticancer Activity In Vitro and In Vivo

    PubMed Central

    Hackler, László; Ózsvári, Béla; Gyuris, Márió; Sipos, Péter; Fábián, Gabriella; Molnár, Eszter; Marton, Annamária; Faragó, Nóra; Mihály, József; Nagy, Lajos István; Szénási, Tibor; Diron, Andrea; Párducz, Árpád; Kanizsai, Iván; Puskás, László G.

    2016-01-01

    C-150 a Mannich-type curcumin derivative, exhibited pronounced cytotoxic effects against eight glioma cell lines at micromolar concentrations. Inhibition of cell proliferation by C-150 was mediated by affecting multiple targets as confirmed at transcription and protein level. C-150 effectively reduced the transcription activation of NFkB, inhibited PKC-alpha which are constitutively over-expressed in glioblastoma. The effects of C-150 on the Akt/ Notch signaling were also demonstrated in a Drosophila tumorigenesis model. C-150 reduced the number of tumors in Drosophila with similar efficacy to mitoxantrone. In an in vivo orthotopic glioma model, C-150 significantly increased the median survival of treated nude rats compared to control animals. The multi-target action of C-150, and its preliminary in vivo efficacy would render this curcumin analogue as a potent clinical candidate against glioblastoma. PMID:26943907

  15. Synthesis of potent and broad genotypically active NS5B HCV non-nucleoside inhibitors binding to the thumb domain allosteric site 2 of the viral polymerase.

    PubMed

    Pierra Rouvière, Claire; Amador, Agnès; Badaroux, Eric; Convard, Thierry; Da Costa, Daniel; Dukhan, David; Griffe, Ludovic; Griffon, Jean-François; LaColla, Massimiliano; Leroy, Frédéric; Liuzzi, Michel; Loi, Anna Giulia; McCarville, Joe; Mascia, Valeria; Milhau, Julien; Onidi, Loredana; Paparin, Jean-Laurent; Rahali, Rachid; Sais, Efisio; Seifer, Maria; Surleraux, Dominique; Standring, David; Dousson, Cyril

    2016-09-15

    The hepatitis C virus (HCV) NS5B RNA-dependent RNA polymerase (RdRp) plays a central role in virus replication. NS5B has no functional equivalent in mammalian cells and, as a consequence, is an attractive target for selective inhibition. This Letter describes the discovery of a new family of HCV NS5B non-nucleoside inhibitors, based on the bioisosterism between amide and phosphonamidate functions. As part of this program, SAR in this new series led to the identification of IDX17119, a potent non-nucleoside inhibitor, active on the genotypes 1b, 2a, 3a and 4a. The structure and binding domain of IDX17119 were confirmed by X-ray co-crystallization study.

  16. The Curcumin Analog C-150, Influencing NF-κB, UPR and Akt/Notch Pathways Has Potent Anticancer Activity In Vitro and In Vivo.

    PubMed

    Hackler, László; Ózsvári, Béla; Gyuris, Márió; Sipos, Péter; Fábián, Gabriella; Molnár, Eszter; Marton, Annamária; Faragó, Nóra; Mihály, József; Nagy, Lajos István; Szénási, Tibor; Diron, Andrea; Párducz, Árpád; Kanizsai, Iván; Puskás, László G

    2016-01-01

    C-150 a Mannich-type curcumin derivative, exhibited pronounced cytotoxic effects against eight glioma cell lines at micromolar concentrations. Inhibition of cell proliferation by C-150 was mediated by affecting multiple targets as confirmed at transcription and protein level. C-150 effectively reduced the transcription activation of NFkB, inhibited PKC-alpha which are constitutively over-expressed in glioblastoma. The effects of C-150 on the Akt/ Notch signaling were also demonstrated in a Drosophila tumorigenesis model. C-150 reduced the number of tumors in Drosophila with similar efficacy to mitoxantrone. In an in vivo orthotopic glioma model, C-150 significantly increased the median survival of treated nude rats compared to control animals. The multi-target action of C-150, and its preliminary in vivo efficacy would render this curcumin analogue as a potent clinical candidate against glioblastoma. PMID:26943907

  17. Efficient radical trapping at the surface and inside the phospholipid membrane is responsible for highly potent antiperoxidative activity of the carotenoid astaxanthin.

    PubMed

    Goto, S; Kogure, K; Abe, K; Kimata, Y; Kitahama, K; Yamashita, E; Terada, H

    2001-06-01

    The effects of the carotenoids beta-carotene and astaxanthin on the peroxidation of liposomes induced by ADP and Fe(2+) were examined. Both compounds inhibited production of lipid peroxides, astaxanthin being about 2-fold more effective than beta-carotene. The difference in the modes of destruction of the conjugated polyene chain between beta-carotene and astaxanthin suggested that the conjugated polyene moiety and terminal ring moieties of the more potent astaxanthin trapped radicals in the membrane and both at the membrane surface and in the membrane, respectively, whereas only the conjugated polyene chain of beta-carotene was responsible for radical trapping near the membrane surface and in the interior of the membrane. The efficient antioxidant activity of astaxanthin is suggested to be due to the unique structure of the terminal ring moiety. PMID:11406102

  18. FRAG1, a gene that potently activates fibroblast growth factor receptor by C-terminal fusion through chromosomal rearrangement.

    PubMed Central

    Lorenzi, M V; Horii, Y; Yamanaka, R; Sakaguchi, K; Miki, T

    1996-01-01

    A constitutively active form of fibroblast growth factor 2 (FGFR2) was identified in rat osteosarcoma (ROS) cells by an expression cloning strategy. Unlike other tyrosine kinase receptors activated by N-terminal truncation in tumors, this receptor, FGFR2-ROS, contains an altered C terminus generated from chromosomal rearrangement with a novel gene, designated FGFR activating gene 1 (FRAG1). While the removal of the C terminus slightly activates FGFR2, the presence of the FRAG1 sequence drastically stimulates the transforming activity and autophosphorylation of the receptor. FGFR2-ROS is expressed as a unusually large protein and is highly phosphorylated in NIH 3T3 transfectants. FRAG1 is ubiquitously expressed and encodes a predicted protein of 28 kDa lacking significant structural similarity to known proteins. Epitope-tagged FRAG1 protein showed a perinuclear localization by immunofluorescence staining. The highly activated state of FGFR2-ROS appears to be attributed to constitutive dimer formation and higher phosphorylation level as well as possibly altered subcellular localization. These results indicate a unique mechanism of receptor activation by a C terminus alteration through a chromosomal fusion with FRAG1. Images Fig. 1 Fig. 2 Fig. 3 Fig. 5 Fig. 6 PMID:8799135

  19. Design of an α-helical antimicrobial peptide with improved cell-selective and potent anti-biofilm activity

    PubMed Central

    Zhang, Shi-Kun; Song, Jin-wen; Gong, Feng; Li, Su-Bo; Chang, Hong-Yu; Xie, Hui-Min; Gao, Hong-Wei; Tan, Ying-Xia; Ji, Shou-Ping

    2016-01-01

    AR-23 is a melittin-related peptide with 23 residues. Like melittin, its high α-helical amphipathic structure results in strong bactericidal activity and cytotoxicity. In this study, a series of AR-23 analogues with low amphipathicity were designed by substitution of Ala1, Ala8 and Ile17 with positively charged residues (Arg or Lys) to study the effect of positively charged residue distribution on the biological viability of the antimicrobial peptide. Substitution of Ile17 on the nonpolar face with positively charged Lys dramatically altered the hydrophobicity, amphipathicity, helicity and the membrane-penetrating activity against human cells as well as the haemolytic activity of the peptide. However, substitution on the polar face only slightly affected the peptide biophysical properties and biological activity. The results indicate that the position rather than the number of positively charged residue affects the biophysical properties and selectivity of the peptide. Of all the analogues, A(A1R, A8R, I17K), a peptide with Ala1-Arg, Ala8-Arg and Ile17-Lys substitutions, exhibited similar bactericidal activity and anti-biofilm activity to AR-23 but had much lower haemolytic activity and cytotoxicity against mammalian cells compared with AR-23. Therefore, the findings reported here provide a rationalization for peptide design and optimization, which will be useful for the future development of antimicrobial agents. PMID:27271216

  20. Small molecule kinase inhibitor LRRK2-IN-1 demonstrates potent activity against colorectal and pancreatic cancer through inhibition of doublecortin-like kinase 1

    PubMed Central

    2014-01-01

    Background Doublecortin-like kinase 1 (DCLK1) is emerging as a tumor specific stem cell marker in colorectal and pancreatic cancer. Previous in vitro and in vivo studies have demonstrated the therapeutic effects of inhibiting DCLK1 with small interfering RNA (siRNA) as well as genetically targeting the DCLK1+ cell for deletion. However, the effects of inhibiting DCLK1 kinase activity have not been studied directly. Therefore, we assessed the effects of inhibiting DCLK1 kinase activity using the novel small molecule kinase inhibitor, LRRK2-IN-1, which demonstrates significant affinity for DCLK1. Results Here we report that LRRK2-IN-1 demonstrates potent anti-cancer activity including inhibition of cancer cell proliferation, migration, and invasion as well as induction of apoptosis and cell cycle arrest. Additionally we found that it regulates stemness, epithelial-mesenchymal transition, and oncogenic targets on the molecular level. Moreover, we show that LRRK2-IN-1 suppresses DCLK1 kinase activity and downstream DCLK1 effector c-MYC, and demonstrate that DCLK1 kinase activity is a significant factor in resistance to LRRK2-IN-1. Conclusions Given DCLK1’s tumor stem cell marker status, a strong understanding of its biological role and interactions in gastrointestinal tumors may lead to discoveries that improve patient outcomes. The results of this study suggest that small molecule inhibitors of DCLK1 kinase should be further investigated as they may hold promise as anti-tumor stem cell drugs. PMID:24885928

  1. Hepatocyte-specific deletion of the keap1 gene activates Nrf2 and confers potent resistance against acute drug toxicity

    SciTech Connect

    Okawa, Hiromi; Motohashi, Hozumi; Kobayashi, Akira; Aburatani, Hiroyuki; Kensler, Thomas W.; Yamamoto, Masayuki . E-mail: masi@tara.tsukuba.ac.jp

    2006-01-06

    Nrf2 is a key regulator of many detoxifying enzyme genes, and cytoplasmic protein Keap1 represses the Nrf2 activity under quiescent conditions. Germ line deletion of the keap1 gene results in constitutive activation of Nrf2, but the pups unexpectedly died before weaning. To investigate how constitutive activation of Nrf2 influences the detoxification system in adult mice, we generated mice bearing a hepatocyte-specific disruption of the keap1 gene. Homozygous mice were viable and their livers displayed no apparent abnormalities, but nuclear accumulation of Nrf2 is elevated. Microarray analysis revealed that, while many detoxifying enzyme genes are highly expressed, some of the typical Nrf2-dependent genes are only marginally increased in the Keap1-deficient liver. The mutant mice were significantly more resistant to toxic doses of acetaminophen than control animals. These results demonstrate that chronic activation of Nrf2 confers animals with resistance to xenobiotics without affecting the morphological and physiological integrity of hepatocytes.

  2. Potent and selective activation of abscisic acid receptors in vivo by mutational stabilization of their agonist-bound conformation

    PubMed Central

    Mosquna, Assaf; Peterson, Francis C.; Park, Sang-Youl; Lozano-Juste, Jorge; Volkman, Brian F.; Cutler, Sean R.

    2011-01-01

    Pyrabactin resistance (PYR) 1 and its relatives belong to a family of soluble abscisic acid (ABA) receptors that inhibit type 2C protein phosphatases (PP2C) when in their agonist-stabilized conformation. Given their switch-like properties, we envisioned that mutations that stabilize their agonist-bound conformation could be used to activate signaling in vivo. To identify such mutations, we subjected PYR1 to site-saturation mutagenesis at 39 highly conserved residues that participate in ABA or PP2C contacts. All 741 possible single amino acid substitutions at these sites were tested to identify variants that increase basal PYR1-PP2C interactions, which uncovered activating mutations in 10 residues that preferentially cluster in PYR1's gate loop and C-terminal helix. The mutations cause measurable but incomplete receptor activation in vitro; however, specific triple and quadruple mutant combinations were constructed that promote an agonist-bound conformation, as measured by heteronuclear single quantum coherence NMR, and lead to full receptor activation. Moreover, these mutations retain functionality when introduced into divergent family members, and can therefore be used to dissect individual receptor function in vivo, which has been problematic because of redundancy and family size. Expression of activated PYL2 in Arabidopsis seeds activates ABA signaling by a number of measures: modulation of ABA-regulated gene expression, induction of hyperdormancy, and suppression of ABA deficiency phenotypes in the aba2-1 mutant. Our results set the stage for systematic gain-of-function studies of PYR1 and related ABA receptors and reveal that, despite the large number of receptors, activation of a single receptor is sufficient to activate signaling in planta. PMID:22139369

  3. Potent Anti-Inflammatory Activity of Ursolic Acid, a Triterpenoid Antioxidant, Is Mediated through Suppression of NF-κB, AP-1 and NF-AT

    PubMed Central

    Checker, Rahul; Sandur, Santosh K.; Sharma, Deepak; Patwardhan, Raghavendra S.; Jayakumar, S.; Kohli, Vineet; Sethi, Gautam; Aggarwal, Bharat B.; Sainis, Krishna B.

    2012-01-01

    Background Ursolic acid (UA), a pentacyclic triterpenoid carboxylic acid, is the major component of many plants including apples, basil, cranberries, peppermint, rosemary, oregano and prunes and has been reported to possess antioxidant and anti-tumor properties. These properties of UA have been attributed to its ability to suppress NF-κB (nuclear factor kappa B) activation. Since NF-κB, in co-ordination with NF-AT (nuclear factor of activated T cells) and AP-1(activator protein-1), is known to regulate inflammatory genes, we hypothesized that UA might exhibit potent anti-inflammatory effects. Methodology/Principal Findings The anti-inflammatory effects of UA were assessed in activated T cells, B cells and macrophages. Effects of UA on ERK, JNK, NF-κB, AP-1 and NF-AT were studied to elucidate its mechanism of action. In vivo efficacy of UA was studied using mouse model of graft-versus-host disease. UA inhibited activation, proliferation and cytokine secretion in T cells, B cells and macrophages. UA inhibited mitogen-induced up-regulation of activation markers and co-stimulatory molecules in T and B cells. It inhibited mitogen-induced phosphorylation of ERK and JNK and suppressed the activation of immunoregulatory transcription factors NF-κB, NF-AT and AP-1 in lymphocytes. Treatment of cells with UA prior to allogenic transplantation significantly delayed induction of acute graft-versus-host disease in mice and also significantly reduced the serum levels of pro-inflammatory cytokines IL-6 and IFN-γ. UA treatment inhibited T cell activation even when added post-mitogenic stimulation demonstrating its therapeutic utility as an anti-inflammatory agent. Conclusions/Significance The present study describes the detailed mechanism of anti-inflammatory activity of UA. Further, UA may find application in the treatment of inflammatory disorders. PMID:22363615

  4. HIV-specific CD4-induced Antibodies Mediate Broad and Potent Antibody-dependent Cellular Cytotoxicity Activity and are Commonly Detected in Plasma from HIV-infected Humans

    PubMed Central

    Williams, Katherine L.; Cortez, Valerie; Dingens, Adam S.; Gach, Johannes S.; Rainwater, Stephanie; Weis, Julie F.; Chen, Xuemin; Spearman, Paul; Forthal, Donald N.; Overbaugh, Julie

    2015-01-01

    HIV-specific antibodies (Abs) can reduce viral burden by blocking new rounds of infection or by destroying infected cells via activation of effector cells through Fc–FcR interaction. This latter process, referred to as antibody-dependent cellular cytotoxicity (ADCC), has been associated with viral control and improved clinical outcome following both HIV and SIV infections. Here we describe an HIV viral-like particle (VLP)-based sorting strategy that led to identification of HIV-specific memory B cells encoding Abs that mediate ADCC from a subtype A-infected Kenyan woman at 914 days post-infection. Using this strategy, 12 HIV-envelope-specific monoclonal antibodies (mAbs) were isolated and three mediated potent ADCC activity when compared to well-characterized ADCC mAbs. The ADCC-mediating Abs also mediated antibody-dependent cell-mediated virus inhibition (ADCVI), which provides a net measure of Fc receptor-triggered effects against replicating virus. Two of the three ADCC-mediating Abs targeted a CD4-induced (CD4i) epitope also bound by the mAb C11; the third antibody targeted the N-terminus of V3. Both CD4i Abs identified here demonstrated strong cross-clade breadth with activity against 10 of 11 envelopes tested, including those from clades A, B, C, A/D and C/D, whereas the V3-specific antibody showed more limited breadth. Variants of these CD4i, C11-like mAbs engineered to interrupt binding to FcγRs inhibited a measurable percentage of the donor's ADCC activity starting as early as 189 days post-infection. C11-like antibodies also accounted for between 18–78% of ADCC activity in 9 chronically infected individuals from the same cohort study. Further, the two CD4i Abs originated from unique B cells, suggesting that antibodies targeting this epitope can be commonly produced. Taken together, these data provide strong evidence that CD4i, C11-like antibodies develop within the first 6 months of infection and they can arise from unique B-cell lineages in the

  5. A Serine Protease Isolated from the Bristles of the Amazonic Caterpillar, Premolis semirufa, Is a Potent Complement System Activator

    PubMed Central

    Villas Boas, Isadora Maria; Pidde-Queiroz, Giselle; Magnoli, Fabio Carlos; Gonçalves-de-Andrade, Rute M.; van den Berg, Carmen W.; Tambourgi, Denise V.

    2015-01-01

    Background The caterpillar of the moth Premolis semirufa, commonly named pararama, is found in the Brazilian Amazon region. Accidental contact with the caterpillar bristles causes an intense itching sensation, followed by symptoms of an acute inflammation, which last for three to seven days after the first incident. After multiple accidents a chronic inflammatory reaction, called “Pararamose”, characterized by articular synovial membrane thickening with joint deformities common to chronic synovitis, frequently occurs. Although complement mediated inflammation may aid the host defense, inappropriate or excessive activation of the complement system and generation of anaphylatoxins can lead to inflammatory disorder and pathologies. The aim of the present study was to evaluate, in vitro, whether the Premolis semirufa’s bristles extract could interfere with the human complement system. Results The bristles extract was able to inhibit the haemolytic activity of the alternative pathway, as well as the activation of the lectin pathway, but had no effect on the classical pathway, and this inhibition seemed to be caused by activation and consumption of complement components. The extract induced the production of significant amounts of all three anaphylatoxins, C3a, C4a and C5a, promoted direct cleavage of C3, C4 and C5 and induced a significant generation of terminal complement complexes in normal human serum. By using molecular exclusion chromatography, a serine protease of 82 kDa, which activates complement, was isolated from P. semirufa bristles extract. The protease, named here as Ps82, reduced the haemolytic activity of the alternative and classical pathways and inhibited the lectin pathway. In addition, Ps82 induced the cleavage of C3, C4 and C5 and the generation of C3a and C4a in normal human serum and it was capable to cleave human purified C5 and generate C5a. The use of Phenanthroline, metalloprotease inhibitor, in the reactions did not significantly

  6. A fibrinolytic protease AfeE from Streptomyces sp. CC5, with potent thrombolytic activity in a mouse model.

    PubMed

    Sun, Zhibin; Liu, Pingping; Cheng, Guangyan; Zhang, Biying; Dong, Weiliang; Su, Xingli; Huang, Yan; Cui, Zhongli; Kong, Yi

    2016-04-01

    Fibrinolytic proteases have potential applications in cardiovascular disease therapy. A novel fibrinolytic protease, AfeE, with strong thrombolytic activity was purified from Streptomyces sp. CC5. AfeE displayed maximum activity at 40°C in the pH range of 7.0-12.0. It was strongly inhibited by serine protease inhibitor phenylmethanesulfonylfluoride, soybean trypsin inhibitor, tosyl-l-lysine chloromethyl ketone and tosyl-l-phenylalanine chloromethyl ketone. The activity of the enzyme was partially inhibited by Cu(2+), Co(2+) and Zn(2+). AfeE exhibited higher substrate specificity for fibrin than fibrinogen, which has rarely been reported in fibrinolytic enzymes. AfeE also showed high thrombolytic activity in a carrageenan-induced mouse tail thrombosis model. AfeE prolonged prothrombin time, activated partial thromboplastin time, and thrombin time in rat blood. A bleeding time assay revealed that AfeE did not prolong bleeding time in mice at a dose of 1mg/kg. No acute cytotoxicity was observed for AfeE at 320μg/well in human umbilical vein endothelial cells. The afeE gene was cloned from the genome of Streptomyces sp. CC5. Full-length AFE-CC5E contained 434 amino acids and was processed into a mature form consisting 284 amino acids by posttranslational modification, as revealed by high-resolution mass spectrometry analysis. These results indicate that AfeE is a prospective candidate for antithrombotic drug development. PMID:26721382

  7. Characterization of Aloeride, a new high-molecular-weight polysaccharide from Aloe vera with potent immunostimulatory activity.

    PubMed

    Pugh, N; Ross, S A; ElSohly, M A; Pasco, D S

    2001-02-01

    We have characterized a new immunostimulatory polysaccharide called Aloeride from commercial aloe vera (Aloe barbadensis) juice. Aloeride is between 4 and 7 million Da, and its glycosyl components include glucose (37.2%), galactose (23.9%), mannose (19.5%), and arabinose (10.3%). At 0.5 microg/mL Aloeride increased NF-kappa B directed luciferase expression in THP-1 human monocytic cells to levels 50% of those achieved by maximal concentrations (10 microg/mL) of LPS. Aloeride induced the expression of the mRNAs encoding IL-1beta and TNF-alpha to levels equal to those observed in cells maximally activated by LPS. Acemannan, the major carbohydrate component from aloe, used at 200 microg/mL in the macrophage assay resulted in negligible NF-kappa B activation. Analysis of acemannan and Aloeride using size-exclusion chromatography suggests that the low activity of acemannan is due to trace amounts of Aloeride. Although Aloeride comprises only 0.015% of the aloe juice dry weight, its potency for macrophage activation accounts fully for the activity of the crude juice.

  8. Orally active opioid μ/δ dual agonist MGM-16, a derivative of the indole alkaloid mitragynine, exhibits potent antiallodynic effect on neuropathic pain in mice.

    PubMed

    Matsumoto, Kenjiro; Narita, Minoru; Muramatsu, Naotaka; Nakayama, Terumi; Misawa, Kaori; Kitajima, Mariko; Tashima, Kimihito; Devi, Lakshmi A; Suzuki, Tsutomu; Takayama, Hiromitsu; Horie, Syunji

    2014-03-01

    (E)-Methyl 2-((2S,3S,7aS,12bS)-3-ethyl-7a-hydroxy-8-methoxy-1,2,3,4,6,7,7a,12b-octahydroindolo[2,3-a]quinolizin-2-yl)-3-methoxyacrylate (7-hydroxymitragynine), a main active constituent of the traditional herbal medicine Mitragyna speciosa, is an indole alkaloid that is structurally different from morphine. 7-Hydroxymitragynine induces a potent antinociceptive effect on mouse acute pain through μ-opioid receptors. In this study, we developed dual-acting μ- and δ-opioid agonists MGM-15 and MGM-16 from 7-hydroxymitragynine for the treatment of acute and chronic pain. MGM-16 showed a higher potency than that of 7-hydroxymitragynine and MGM-15 in in vitro and in vivo assays. MGM-16 exhibited a high affinity for μ- and δ-opioid receptors, with K(i) values of 2.1 and 7.0 nM, respectively. MGM-16 showed μ- and δ-opioid full agonistic effects in a guanosine 5'-O-(3-[(35)S]thiotriphosphate) binding assay and in a functional test using electrically elicited guinea pig ileum and mouse vas deferens contractions. Systemic administration of MGM-16 produced antinociceptive effects in a mouse acute pain model and antiallodynic effects in a chronic pain model. The antinociceptive effect of MGM-16 was approximately 240 times more potent than that of morphine in a mouse tail-flick test, and its antiallodynic effect was approximately 100 times more potent than that of gabapentin in partial sciatic nerve-ligated mice, especially with oral administration. The antinociceptive effect of MGM-16 was completely and partially blocked by the μ-selective antagonist β-funaltrexamine hydrochloride (β-FNA) and by the δ-selective antagonist naltrindole, respectively, in a tail-flick test. The antiallodynic effect of MGM-16 was completely blocked by β-FNA and naltrindole in a neuropathic pain model. These findings suggest that MGM-16 could become a class of a compound with potential therapeutic utility for treating neuropathic pain. PMID:24345467

  9. Anti cancer activity on Graviola, an exciting medicinal plant extract vs various cancer cell lines and a detailed computational study on its potent anti-cancerous leads.

    PubMed

    Paul, Jeno; Gnanam, R; Jayadeepa, R M; Arul, L

    2013-01-01

    Nature is the world's best chemist: Many naturally occurring compounds have very complicated structures that present great challenges to chemists wishing to determine their structures or replicate them. The plant derived herbal compounds have a long history of clinical use, better patient tolerance and acceptance. Their high ligand binding affinity to the target introduce the prospect of their use in chemo preventive applications; in addition they are freely available natural compounds that can be safely used to prevent various ailments. Plants became the basis of traditional medicine system throughout the world for thousands of years and continue to provide mankind with new remedies. Here, we present a research study on a medicinal plant, Graviola, a native of North America but rarely grown in India. It has a wide potent anticancerous agents coined as Acetogenins which play a key role towards many varieties of cancer, Acetogenins are potent inhibitors of NADH oxidase of the plasma membranes of cancer cells. Potent leads were taken for the study through literature survey, major types of cancer targets were identified, the natureceuticals and the cancer protein were subjected to docking analysis, further with the help of the dock score and other descriptor properties top ranked molecules were collected, commercial drug was also selected and identified as a Test compound for the study. Later, the phytochemicals were subjected to toxicity analysis. Those screened compounds were then considered for active site analysis and to find the best binding site for the study. R Programming library was used to find the best leads. Phytochemicals such as Anonaine, Friedelin, Isolaureline, Annonamine, Anomurine, Kaempferol, Asimilobine, Quercetin, Xylopine were clustered and the highly clustered compounds such as Annonamine , Kaempferol termed to be a potential lead for the study. Further study on experimental analysis may prove the potentiality of these compounds. In the

  10. Lipophilic stinging nettle extracts possess potent anti-inflammatory activity, are not cytotoxic and may be superior to traditional tinctures for treating inflammatory disorders

    PubMed Central

    Johnson, Tyler A.; Sohn, Johann; Inman, Wayne D.; Bjeldanes, Leonard F.; Rayburn, Keith

    2012-01-01

    Extracts of four plant portions (roots, stems, leaves and flowers) of Urtica dioica, (the stinging nettle) were prepared using accelerated solvent extraction (ASE) involving water, hexanes, methanol and dichloromethane. The extracts were evaluated for their anti-inflammatory and cytotoxic activity in an NF-κB luciferase and MTT assay using macrophage immune (RAW264.7) cells. A standardized commercial ethanol extract of nettle leaves were also evaluated. The methanolic extract of the flowering portions displayed significant anti-inflammatory activity on par with the standard anti-inflammatory agent celastrol (1) but was moderately cytotoxic. Alternatively, the polar extracts (water, methanol, ethanol) of the roots, stems and leaves plant portions displayed moderate to weak anti-inflammatory activity, while the methanol and especially the water soluble extracts exhibited noticeable cytotoxicity. In contrast, the lipophilic dichloromethane extracts of the roots, stems and leaves exhibited potent anti-inflammatory effects ≥ 1 with minimal cytotoxicity to RAW264.7 cells. Collectively these results suggest that using lipophilic extracts of the roots, stems or leaves of stinging nettle may be more effective then traditional tinctures (water, methanol, ethanol) to undergo clinical evaluations for the treatment of inflammatory disorders including arthritis. A chemical investigation into the lipophillic extracts of stinging nettle to identify the bioactive compound(s) responsible for their observed anti-inflammatory activity is further warranted. PMID:23092723

  11. Lipophilic stinging nettle extracts possess potent anti-inflammatory activity, are not cytotoxic and may be superior to traditional tinctures for treating inflammatory disorders.

    PubMed

    Johnson, Tyler A; Sohn, Johann; Inman, Wayne D; Bjeldanes, Leonard F; Rayburn, Keith

    2013-01-15

    Extracts of four plant portions (roots, stems, leaves and flowers) of Urtica dioica (the stinging nettle) were prepared using accelerated solvent extraction (ASE) involving water, hexanes, methanol and dichloromethane. The extracts were evaluated for their anti-inflammatory and cytotoxic activities in an NF-κB luciferase and MTT assay using macrophage immune (RAW264.7) cells. A standardized commercial ethanol extract of nettle leaves was also evaluated. The methanolic extract of the flowering portions displayed significant anti-inflammatory activity on par with a standard compound celastrol (1) but were moderately cytotoxic. Alternatively, the polar extracts (water, methanol, ethanol) of the roots, stems and leaves displayed moderate to weak anti-inflammatory activity, while the methanol and especially the water soluble extracts exhibited noticeable cytotoxicity. In contrast, the lipophilic dichloromethane extracts of the roots, stems and leaves exhibited potent anti-inflammatory effects greater than or equal to 1 with minimal cytotoxicity to RAW264.7 cells. Collectively these results suggest that using lipophilic extracts of stinging nettle may be more effective than traditional tinctures (water, methanol, ethanol) in clinical evaluations for the treatment of inflammatory disorders especially arthritis. A chemical investigation into the lipophilic extracts of stinging nettle to identify the bioactive compound(s) responsible for their observed anti-inflammatory activity is further warranted. PMID:23092723

  12. Isolation of peptides of the brevinin-1 family with potent candidacidal activity from the skin secretions of the frog Rana boylii.

    PubMed

    Conlon, J M; Sonnevend, A; Patel, M; Davidson, C; Nielsen, P F; Pál, T; Rollins-Smith, L A

    2003-11-01

    The emergence of strains of the human pathogen Candida albicans with resistance to commonly used antibiotics has necessitated a search for new types of antifungal agents. Six peptides with antimicrobial activity were isolated from norepinephrine-stimulated skin secretions from the foothill yellow-legged frog Rana boylii. Brevinin-1BYa (FLPILASLAA10KFGPKLF CLV20TKKC) was particularly potent against C. albicans [minimal inhibitory concentration (MIC) = 3 microm] and also active against Escherichia coli (MIC = 17 microm) and Staphylococcus aureus (MIC = 2 microm), but its therapeutic potential for systemic use is limited by its strong hemolytic activity (HC50 = 4 microm). The single amino acid substitution (Phe12 --> Leu) in brevinin-1BYb resulted in a fourfold lower potency against C. albicans and the additional amino acid substitutions (Lys11 --> Thr, Phe17 --> Leu and Val20 --> Ile) in brevinin-1BYc resulted in a ninefold decrease in activity. Two members of the ranatuerin-2 family and one member of the temporin family were also isolated from the secretions but showed relatively low potency against the three microorganisms tested.

  13. The prenylflavonoid isoxanthohumol from hops (Humulus lupulus L.) is activated into the potent phytoestrogen 8-prenylnaringenin in vitro and in the human intestine.

    PubMed

    Possemiers, Sam; Bolca, Selin; Grootaert, Charlotte; Heyerick, Arne; Decroos, Karel; Dhooge, Willem; De Keukeleire, Denis; Rabot, Sylvie; Verstraete, Willy; Van de Wiele, Tom

    2006-07-01

    Hops, an essential beer ingredient, are a source of prenylflavonoids, including 8-prenylnaringenin (8-PN), one of the most potent phytoestrogens. Because 8-PN concentrations in beers are generally low, its health effects after moderate beer consumption were considered negligible. However, human intestinal microbiota may activate up to 4 mg/L isoxanthohumol (IX) in beer into 8-PN. Depending on interindividual differences in the intestinal transformation potential, this conversion could easily increase the 8-PN exposure 10-fold upon beer consumption. Here, we present a further investigation of the process both in vitro and in vivo. In vitro experiments with the dynamic SHIME model showed that hop prenylflavonoids pass unaltered through the stomach and small intestine and that activation of IX into 8-PN (up to 80% conversion) occurs only in the distal colon. In vitro incubations of 51 fecal samples from female volunteers with IX enabled us to separate the fecal microbiota into high (8 of 51), moderate (11 of 51) and slow (32 of 51) 8-PN producers, clearly illustrating an interindividual variability. Three women, selected from the respective groups, received a daily dose of 5.59 mg IX for 4 d. Intestinal IX activation and urinary 8-PN excretion were correlated (R(2) = 0.6417, P < 0.01). These data show that intestinal conversion of IX upon moderate beer consumption can lead to 8-PN exposure values that might fall within the range of human biological activity.

  14. The latex sap of the 'Old World Plant' Lagenaria siceraria with potent lectin activity mitigates neoplastic malignancy targeting neovasculature and cell death.

    PubMed

    Vigneshwaran, V; Thirusangu, Prabhu; Madhusudana, S; Krishna, V; Pramod, Siddanakoppalu N; Prabhakar, B T

    2016-10-01

    Lifestyle and dietary modifications have contributed much to somatic genetic alteration which has concomitantly led to increase in malignant diseases. Henceforth, plant based and dietary interventions to mitigate and impede oncogenic transformation are in great demand. We investigated the latex sap (LSL) of the dietary Lagenaria siceraria vegetable, the first domesticated plant species with the potent lectin activity for its functional role against the tumor progression and its mechanism. LSL has markedly stimulated proliferation of lymphocytes and displayed strong cytotoxic activity against cancer both in-vitro and in-vivo. The tumor regression was paralleled with drastic reduction in tumoral neovasculature as evidenced from angiogenic parameters and abrogated related gene expressions. LSL has also triggered apoptotic signaling cascade in cancer cells through activation of caspase-3 mediated activation of endonuclease and inducing apoptotic cellular events. Collectively our study provides tangible evidences that latex sap from L. siceraria with immunopotentiating ability significantly regresses the tumor progression by targeting angiogenesis and inducing cell death. PMID:27475665

  15. A Highly Pure Sub-Fraction of Shallot Extract With Potent in vitro Anti-Angiogenic Activity

    PubMed Central

    Famil Samavati, Shima; Mohammadi-Motlagh, Hamid-Reza; Mostafaie, Ali

    2014-01-01

    Our previous studies showed that various extracts of Persian shallot (Allium hirtifolium) have anti- angiogenic effects. This study has been undertaken to isolate and identify the major effective anti- angiogeneic sub-fraction of shallot. After preparation of the 50% hydroalcoholic extract of shallot bulbs, the extract was successively fractionated into n- hexane, ethyl acetate, n- butanol and aqueous fractions. Anti-angiogenesis activity of fractions was examined by in vitro angiogenesis assay. The ethyl acetate fraction which had the most anti-angiogenesis activity was further fractionated to four sub- fractions by thin layer chromatography (TLC), silica gel column chromatography and then analyzed by High Performance TLC (HPTLC) with ethyl acetate-methanol- water as the solvent system. Our results showed that one of the four sub- fractions, as the major band in HPTLC, had the most anti- angiogenic activity. Purification and characterization of the major anti- angiogenic compound/compounds of shallot's extract may constitute one means by which diets rich in shallot confer protection against cancer and finally introduce new agents with pharmacological activities in shallot as a potential candidate in cancer therapy. PMID:25635250

  16. A Highly Pure Sub-Fraction of Shallot Extract With Potent in vitro Anti-Angiogenic Activity.

    PubMed

    Famil Samavati, Shima; Mohammadi-Motlagh, Hamid-Reza; Mostafaie, Ali

    2014-01-01

    Our previous studies showed that various extracts of Persian shallot (Allium hirtifolium) have anti- angiogenic effects. This study has been undertaken to isolate and identify the major effective anti- angiogeneic sub-fraction of shallot. After preparation of the 50% hydroalcoholic extract of shallot bulbs, the extract was successively fractionated into n- hexane, ethyl acetate, n- butanol and aqueous fractions. Anti-angiogenesis activity of fractions was examined by in vitro angiogenesis assay. The ethyl acetate fraction which had the most anti-angiogenesis activity was further fractionated to four sub- fractions by thin layer chromatography (TLC), silica gel column chromatography and then analyzed by High Performance TLC (HPTLC) with ethyl acetate-methanol- water as the solvent system. Our results showed that one of the four sub- fractions, as the major band in HPTLC, had the most anti- angiogenic activity. Purification and characterization of the major anti- angiogenic compound/compounds of shallot's extract may constitute one means by which diets rich in shallot confer protection against cancer and finally introduce new agents with pharmacological activities in shallot as a potential candidate in cancer therapy.

  17. Polyphenolics from various extracts/fractions of red onion (Allium cepa) peel with potent antioxidant and antimutagenic activities.

    PubMed

    Singh, Brahma N; Singh, B R; Singh, R L; Prakash, D; Singh, D P; Sarma, B K; Upadhyay, G; Singh, H B

    2009-06-01

    In order to determine antioxidant activity, the five extracts/fractions of red onion peel were studied for their total content of phenolics (TPC), flavonoids (TFC), antioxidant activity (AOA), free radical scavenging activity (FRSA), assayed by DPPH radical in the terms of anti-radical power (ARP) and reducing power (RP), expressed as ascorbic acid equivalents (ASE)/ml. High TPC (384.7 +/- 5.0 mg GAE/g), TFC (165.2+/- 3.2 mg QE/g), AOA (97.4 +/- 7.6%), ARP (75.3 +/-4.5) and RP (1.6 +/-0.3 ASE/ml) were found for the ethyl acetate (EA) fraction. EA fraction had markedly higher antioxidant capacity than butylated hydroxytoluene (BHT) in preventive or scavenging capacities against FeCl3-induced lipid peroxidation, protein fragmentation, hydroxyl (site-specific and non-site-specific), superoxide anion and nitric oxide radicals. EA fraction also showed dose dependent antimutagenic activity by following the inhibition of tobacco-induced mutagenicity in Salmonella typhimurium strains (TA102) and hydroxyl radical-induced nicking in plasmid pUC18 DNA. HPLC and MS/MS analysis showed the presence of ferulic, gallic, protocatechuic acids, quercetin and kaempferol. The large amount of polyphenols contained in EA fraction may cause its strong antioxidant and antimutagenic properties. This information shows that EA fraction of red onion peel can be used as natural antioxidant in nutraceutical preparations. PMID:19425188

  18. A Highly Pure Sub-Fraction of Shallot Extract With Potent in vitro Anti-Angiogenic Activity.

    PubMed

    Famil Samavati, Shima; Mohammadi-Motlagh, Hamid-Reza; Mostafaie, Ali

    2014-01-01

    Our previous studies showed that various extracts of Persian shallot (Allium hirtifolium) have anti- angiogenic effects. This study has been undertaken to isolate and identify the major effective anti- angiogeneic sub-fraction of shallot. After preparation of the 50% hydroalcoholic extract of shallot bulbs, the extract was successively fractionated into n- hexane, ethyl acetate, n- butanol and aqueous fractions. Anti-angiogenesis activity of fractions was examined by in vitro angiogenesis assay. The ethyl acetate fraction which had the most anti-angiogenesis activity was further fractionated to four sub- fractions by thin layer chromatography (TLC), silica gel column chromatography and then analyzed by High Performance TLC (HPTLC) with ethyl acetate-methanol- water as the solvent system. Our results showed that one of the four sub- fractions, as the major band in HPTLC, had the most anti- angiogenic activity. Purification and characterization of the major anti- angiogenic compound/compounds of shallot's extract may constitute one means by which diets rich in shallot confer protection against cancer and finally introduce new agents with pharmacological activities in shallot as a potential candidate in cancer therapy. PMID:25635250

  19. Lactobacillus rhamnosus strain GG restores alkaline phosphatase activity in differentiating Caco-2 cells dosed with the potent mycotoxin deoxynivalenol.

    PubMed

    Turner, P C; Wu, Q K; Piekkola, S; Gratz, S; Mykkänen, H; El-Nezami, H

    2008-06-01

    Deoxynivalenol (DON) contamination of cereal crops occurs frequently, and may cause acute exposure at high levels or chronic more moderate exposure. DON has proven toxicity including restriction of enterocyte differentiation, which may play a part in DON induced gastroenteritis. The probiotic bacteria Lactobacillus rhamnosus strain GG (GG) can bind DON, and therefore potentially restrict bioavailability of this toxin. Binding efficacy is not significantly altered by heat treatment, and therefore this in vitro study evaluated whether heat inactivated GG could restore the differentiation process in Caco-2 cells, using alkaline phosphatase (ALP) activity as a marker of differentiation. DON (200ng/mL) caused a significant (p<0.001) 36% reduction in ALP activity (1598+/-137U/mg protein) compared to untreated cells (2502+/-80U/mg). A dose dependant restoration of ALP activity was observed where DON treated cells were co-incubated with heat inactivated GG (1719+/-84; 2007+/-142; 2272+/-160U/mg for GG at 1x10(4) (p>0.9), 1x10(7) (p<0.001), and 1x10(10)CFU/mL (p<0.001), respectively). Co-incubation of the non-binding strain, LC-705 (1x10(10)CFU/mL), with DON did not significantly restore the ALP (1841+/-97U/mg, p<0.077) compared to DON only treated cells. When viable GG were co-incubated with DON a similar restoration of ALP activity was observed as seen for heat inactivated GG. These combined data suggest that the major effect of GG on restoring ALP activity, and therefore Caco-2 cell differentiation, was due to specific binding of DON, with possibly a more minor role of non-specific bacterial interference.

  20. Characteristics of a group of nonnucleoside reverse transcriptase inhibitors with structural diversity and potent anti-human immunodeficiency virus activity.

    PubMed

    Yang, S S; Fliakas-Boltz, V; Bader, J P; Buckheit, R W

    1995-10-01

    Current thrust in controlling the Acquired Immune Deficiency Syndrome (AIDS) focuses on antiviral drug development targeting the infection and replication of the human immunodeficiency virus (HIV), the causative agent of AIDS. To date, treatment of AIDS has relied on nucleoside reverse transcriptase inhibitors such as AZT, ddI, and ddC, which eventually become ineffective upon the emergence of resistant mutants bearing specific nucleotide substitutions. The Anti-AIDS Drug Screening Program of the NCI conducts and coordinates a high-capacity semi-robotic in vitro screening of synthetic or natural compounds submitted by academic, research and pharmaceutical institutions world-wide. About 10,000 synthetic compounds are screened annually for anti-HIV activity. Confirmed active agents are subjected to in-depth studies on range and mechanism of action. Emerging from this intense screening activity were a number of potentially promising categories of nonnucleoside reverse transcriptase inhibitors (NNRTI) with structural diversity but strong and reproducible anti-HIV activity. Over 2500 active compounds were evaluated for their inhibitory activity against a panel of both laboratory and clinical virus isolates in the appropriate established cell line or fresh human peripheral blood leukocyte and macrophage preparations. Out of these, 40 agents could be placed structurally in nine categories with an additional 16 unique compounds that share the characteristics of NNRTI. These NNRTIs were shown to inhibit reverse transcriptase enzymatically using homopolymeric or ribosomal RNA as templates. NNRTIs demonstrated similarity in their inhibitory pattern against the HIV-1 laboratory strains IIIB and RF, and an AZT-resistant strain; all were inactive against HIV-2. These compounds were further tested against NNRTI-resistant HIV-1 isolates. NNRTI-resistant HIV-1 isolates were selected and characterized with respect to the change(s) in the viral reverse transcriptase nucleotide

  1. Regorafenib (BAY 73-4506): a new oral multikinase inhibitor of angiogenic, stromal and oncogenic receptor tyrosine kinases with potent preclinical antitumor activity.

    PubMed

    Wilhelm, Scott M; Dumas, Jacques; Adnane, Lila; Lynch, Mark; Carter, Christopher A; Schütz, Gunnar; Thierauch, Karl-Heinz; Zopf, Dieter

    2011-07-01

    Angiogenesis, a critical driver of tumor development, is controlled by interconnected signaling pathways. Vascular endothelial growth factor receptor (VEGFR) 2 and tyrosine kinase with immunoglobulin and epidermal growth factor homology domain 2 play crucial roles in the biology of normal and tumor vasculature. Regorafenib (BAY 73-4506), a novel oral multikinase inhibitor, potently inhibits these endothelial cell kinases in biochemical and cellular kinase phosphorylation assays. Furthermore, regorafenib inhibits additional angiogenic kinases (VEGFR1/3, platelet-derived growth factor receptor-β and fibroblast growth factor receptor 1) and the mutant oncogenic kinases KIT, RET and B-RAF. The antiangiogenic effect of regorafenib was demonstrated in vivo by dynamic contrast-enhanced magnetic resonance imaging. Regorafenib administered once orally at 10 mg/kg significantly decreased the extravasation of Gadomer in the vasculature of rat GS9L glioblastoma tumor xenografts. In a daily (qd)×4 dosing study, the pharmacodynamic effects persisted for 48 hr after the last dosing and correlated with tumor growth inhibition (TGI). A significant reduction in tumor microvessel area was observed in a human colorectal xenograft after qd×5 dosing at 10 and 30 mg/kg. Regorafenib exhibited potent dose-dependent TGI in various preclinical human xenograft models in mice, with tumor shrinkages observed in breast MDA-MB-231 and renal 786-O carcinoma models. Pharmacodynamic analyses of the breast model revealed strong reduction in staining of proliferation marker Ki-67 and phosphorylated extracellular regulated kinases 1/2. These data demonstrate that regorafenib is a well-tolerated, orally active multikinase inhibitor with a distinct target profile that may have therapeutic benefit in human malignancies.

  2. Characterization of the potent luteinizing hormone-releasing activity of KiSS-1 peptide, the natural ligand of GPR54.

    PubMed

    Navarro, V M; Castellano, J M; Fernández-Fernández, R; Tovar, S; Roa, J; Mayen, A; Nogueiras, R; Vazquez, M J; Barreiro, M L; Magni, P; Aguilar, E; Dieguez, C; Pinilla, L; Tena-Sempere, M

    2005-01-01

    Loss-of-function mutations of the gene encoding GPR54, the putative receptor for the KiSS-1-derived peptide metastin, have been recently associated with hypogonadotropic hypogonadism, in both rodents and humans. Yet the actual role of the KiSS-1/GPR54 system in the neuroendocrine control of gonadotropin secretion remains largely unexplored. To initiate such analysis, the effects of KiSS-1 peptide on LH secretion were monitored using in vivo and in vitro settings under different experimental conditions. Central intracerebroventricular administration of KiSS-1 peptide potently elicited LH secretion in vivo over a range of doses from 10 pmol to 1 nmol. The effect of centrally injected KiSS-1 appeared to be mediated via the hypothalamic LHRH. However, no effect of central administration of KiSS-1 was detected on relative LHRH mRNA levels. Likewise, systemic (i.p. and i.v.) injection of KiSS-1 markedly stimulated LH secretion. This effect was similar in terms of maximum response to that of central administration of KiSS-1 and might be partially attributed to its ability to stimulate LH secretion directly at the pituitary. Finally, the LH-releasing activity of KiSS-1 was persistently observed after blockade of endogenous excitatory amino acid and nitric oxide pathways, i.e. relevant neurotransmitters in the neuroendocrine control of LH secretion. In summary, our results provide solid evidence for a potent stimulatory effect of KiSS-1 on LH release, acting at central levels (likely the hypothalamus) and eventually at the pituitary, and further document a novel role of the KiSS-1/GPR54 system as a relevant downstream element in the neuroendocrine network governing LH secretion. PMID:15375028

  3. Tuning sensitivity of CAR to EGFR density limits recognition of normal tissue while maintaining potent anti-tumor activity

    PubMed Central

    Caruso, Hillary G.; Hurton, Lenka V.; Najjar, Amer; Rushworth, David; Ang, Sonny; Olivares, Simon; Mi, Tiejuan; Switzer, Kirsten; Singh, Harjeet; Huls, Helen; Lee, Dean A.; Heimberger, Amy B.; Champlin, Richard E.; Cooper, Laurence J. N.

    2015-01-01

    Many tumors over express tumor-associated antigens relative to normal tissue, such as epidermal growth factor receptor (EGFR). This limits targeting by human T cells modified to express chimeric antigen receptors (CARs) due to potential for deleterious recognition of normal cells. We sought to generate CAR+ T cells capable of distinguishing malignant from normal cells based on the disparate density of EGFR expression by generating two CARs from monoclonal antibodies which differ in affinity. T cells with low affinity Nimo-CAR selectively targeted cells over-expressing EGFR, but exhibited diminished effector function as the density of EGFR decreased. In contrast, the activation of T cells bearing high affinity Cetux-CAR was not impacted by the density of EGFR. In summary, we describe the generation of CARs able to tune T-cell activity to the level of EGFR expression in which a CAR with reduced affinity enabled T cells to distinguish malignant from non-malignant cells. PMID:26330164

  4. Development of DANDYs, new 3,5-diaryl-7-azaindoles demonstrating potent DYRK1A kinase inhibitory activity.

    PubMed

    Gourdain, Stéphanie; Dairou, Julien; Denhez, Clément; Bui, Linh Chi; Rodrigues-Lima, Fernando; Janel, Nathalie; Delabar, Jean M; Cariou, Kevin; Dodd, Robert H

    2013-12-12

    A series of 3,5-diaryl-1H-pyrrolo[2,3-b]pyridines were synthesized and evaluated for inhibition of DYRKIA kinase in vitro. Derivatives having hydroxy groups on the aryl moieties (2c, 2j-l) demonstrated high inhibitory potencies with Kis in the low nanomolar range. Their methoxy analogues were up to 100 times less active. Docking studies at the ATP binding site suggested that these compounds bind tightly to this site via a network of multiple H-bonds with the peptide backbone. None of the active compounds were cytotoxic to KB cells at 10(-6) M. Kinase profiling revealed that compound 2j showed 2-fold selectivity for DYRK1A with respect to DYRK2 and DYRK3. PMID:24188002

  5. Potent biphalin analogs with µ/δ mixed opioid activity: in vivo and in vitro biological evaluation.

    PubMed

    Costante, Roberto; Pinnen, Francesco; Stefanucci, Azzurra; Mollica, Adriano

    2014-05-01

    Biphalin [(Tyr-D-Ala-Gly-Phe-NH-)2 ] is an octapeptide with mixed μ/δ opioid activity. Its structure is based on two identical enkephalin-like portions linked "tail-to-tail" by a hydrazine bridge. This study presents the synthesis and in vitro and in vivo bioassays of two biphalin analogs that do not present the toxicity connected with the presence of the hydrazine moiety and are able to elicit a higher antinociceptive effect than biphalin. PMID:24798820

  6. MK-4101, a Potent Inhibitor of the Hedgehog Pathway, Is Highly Active against Medulloblastoma and Basal Cell Carcinoma.

    PubMed

    Filocamo, Gessica; Brunetti, Mirko; Colaceci, Fabrizio; Sasso, Romina; Tanori, Mirella; Pasquali, Emanuela; Alfonsi, Romina; Mancuso, Mariateresa; Saran, Anna; Lahm, Armin; Di Marcotullio, Lucia; Steinkühler, Christian; Pazzaglia, Simonetta

    2016-06-01

    Aberrant activation of the Hedgehog (Hh) signaling pathway is implicated in the pathogenesis of many cancers, including medulloblastoma and basal cell carcinoma (BCC). In this study, using neonatally irradiated Ptch1(+/-) mice as a model of Hh-dependent tumors, we investigated the in vivo effects of MK-4101, a novel SMO antagonist, for the treatment of medulloblastoma and BCC. Results clearly demonstrated a robust antitumor activity of MK-4101, achieved through the inhibition of proliferation and induction of extensive apoptosis in tumor cells. Of note, beside antitumor activity on transplanted tumors, MK-4101 was highly efficacious against primary medulloblastoma and BCC developing in the cerebellum and skin of Ptch1(+/-) mice. By identifying the changes induced by MK-4101 in gene expression profiles in tumors, we also elucidated the mechanism of action of this novel, orally administrable compound. MK-4101 targets the Hh pathway in tumor cells, showing the maximum inhibitory effect on Gli1 MK-4101 also induced deregulation of cell cycle and block of DNA replication in tumors. Members of the IGF and Wnt signaling pathways were among the most highly deregulated genes by MK-4101, suggesting that the interplay among Hh, IGF, and Wnt is crucial in Hh-dependent tumorigenesis. Altogether, the results of this preclinical study support a therapeutic opportunity for MK-4101 in the treatment of Hh-driven cancers, also providing useful information for combination therapy with drugs targeting pathways cooperating with Hh oncogenic activity. Mol Cancer Ther; 15(6); 1177-89. ©2016 AACR. PMID:26960983

  7. Activity of quinfamide against natural infections of Entamoeba criceti in hamsters: a new potent agent for intestinal amoebiasis.

    PubMed

    Slighter, R G; Yarinsky, A; Drobeck, H P; Bailey, D M

    1980-08-01

    A novel tetrahydroquinolinyl ester, quinfamide, administered orally in multiple doses for 3 days had an ED50 of 0.25 mg/kg/day (total dose 0.75 mg/kg) for eradicating Entamoeba criceti in hamsters in several tests. It was significantly more active by direct comparison than 3 commercially available amoebicides and at least as active as 2 other esters of the parent compound, 1-(dichloroacety)-1,2,3,4-tetrahydro-6-quinolinol. After administration of a single dose, ED50 calculations for quinfamide averaged 0.9 mg/kg. Quinfamide was considerably more active than the other tetrahydroquinolinols, diloxanide furoate and teclozan, and it was approximately 1.5 times more active than etofamide; a statistical significance between the latter 2 drugs could be demonstrated in one of 4 tests. Administered prophylactically, quinfamide was shown to protect hamsters from re-infection with E. criceti. It also inhibited propagation of E. histolytica in vitro at a concentration of 20 microgram/ml. No adverse effects were noted in rodents after a single dose as high as 10 g/kg. Daily administration to monkeys of doses up to 500 mg/kg for as long as 37 days produced no pharmacological aberrations during or after medication; haematological studies and urine analyses were normal and no gross or microscopical tissue changes attributable to quinfamide were observed. No toxicity was revealed following acute (2 g/kg) and chronic (500 mg/kg/day x 31 days) administration of the drug to dogs and rats, respectively.

  8. Influence of ring size on the cognition-enhancing activity of DM235 and MN19, two potent nootropic drugs.

    PubMed

    Guandalini, L; Martini, E; Di Cesare Mannelli, L; Dei, S; Manetti, D; Scapecchi, S; Teodori, E; Ghelardini, C; Romanelli, M N

    2012-03-01

    A series of analogs of DM235 and MN19, characterized by rings with different size, have been prepared and evaluated for their nootropic activity in the mouse passive-avoidance test. It was found that the optimal ring size for the analogs of DM235, showing endocyclic both amidic groups, is 6 or 7 atoms. For the compounds structurally related to MN19, carrying an exocyclic amide group, the piperidine ring is the moiety which gives the most interesting compounds.

  9. A lectin with highly potent inhibitory activity toward breast cancer cells from edible tubers of Dioscorea opposita cv. nagaimo.

    PubMed

    Chan, Yau Sang; Ng, Tzi Bun

    2013-01-01

    A 70-kDa galactose-specific lectin was purified from the tubers of Dioscorea opposita cv. nagaimo. The purification involved three chromatographic steps: anion exchange chromatography on a Q-Sepharose column, FPLC-anion exchange chromatography on a Mono Q column, and FPLC-gel filtration on a Superdex 75 column. The purified nagaimo lectin presented as a single 35-kDa band in reducing SDS-PAGE while it exhibited a 70-kDa single band in non-reducing SDS-PAGE suggesting its dimeric nature. Nagaimo lectin displayed moderate thermostability, retaining full hemagglutinating activity after heating up to 62°C for 30 minutes. It also manifested stability over a wide pH range from pH 2 to 13. Nagaimo lectin was a galactose-specific lectin, as evidenced by binding with galactose and galactose-containing sugars such as lactose and raffinose. The minimum concentration of galactose, lactose and raffinose required to exert an inhibitory effect on hemagglutinating activity of nagaimo lectin was 20 mM, 5 mM and 40 mM, respectively. Nagaimo lectin inhibited the growth of some cancer cell lines including breast cancer MCF7 cells, hepatoma HepG2 cells and nasopharyngeal carcinoma CNE2 cells, with IC(50) values of 3.71 µM, 7.12 µM and 19.79 µM, respectively, after 24 hour treatment with nagaimo lectin. The induction of phosphatidylserine externalization and mitochondrial depolarization indicated that nagaimo lectin evoked apoptosis in MCF7 cells. However, the anti-proliferative activity of nagaimo lectin was not blocked by application of galactose, signifying that the activity was not related to the carbohydrate binding specificity of the lectin. PMID:23349827

  10. A Lectin with Highly Potent Inhibitory Activity toward Breast Cancer Cells from Edible Tubers of Dioscorea opposita cv. Nagaimo

    PubMed Central

    Chan, Yau Sang; Ng, Tzi Bun

    2013-01-01

    A 70-kDa galactose-specific lectin was purified from the tubers of Dioscorea opposita cv. nagaimo. The purification involved three chromatographic steps: anion exchange chromatography on a Q-Sepharose column, FPLC-anion exchange chromatography on a Mono Q column, and FPLC-gel filtration on a Superdex 75 column. The purified nagaimo lectin presented as a single 35-kDa band in reducing SDS-PAGE while it exhibited a 70-kDa single band in non-reducing SDS-PAGE suggesting its dimeric nature. Nagaimo lectin displayed moderate thermostability, retaining full hemagglutinating activity after heating up to 62°C for 30 minutes. It also manifested stability over a wide pH range from pH 2 to 13. Nagaimo lectin was a galactose-specific lectin, as evidenced by binding with galactose and galactose-containing sugars such as lactose and raffinose. The minimum concentration of galactose, lactose and raffinose required to exert an inhibitory effect on hemagglutinating activity of nagaimo lectin was 20 mM, 5 mM and 40 mM, respectively. Nagaimo lectin inhibited the growth of some cancer cell lines including breast cancer MCF7 cells, hepatoma HepG2 cells and nasopharyngeal carcinoma CNE2 cells, with IC50 values of 3.71 µM, 7.12 µM and 19.79 µM, respectively, after 24 hour treatment with nagaimo lectin. The induction of phosphatidylserine externalization and mitochondrial depolarization indicated that nagaimo lectin evoked apoptosis in MCF7 cells. However, the anti-proliferative activity of nagaimo lectin was not blocked by application of galactose, signifying that the activity was not related to the carbohydrate binding specificity of the lectin. PMID:23349827

  11. Incorporation of Bulky and Cationic Cyclam-Triazole Moieties into Marimastat Can Generate Potent MMP Inhibitory Activity without Inducing Cytotoxicity

    PubMed Central

    Yu, Mingfeng; Lim, Ngee H; Ellis, Samantha; Nagase, Hideaki; Triccas, James A; Rutledge, Peter J; Todd, Matthew H

    2013-01-01

    The synthesis and matrix metalloproteinase (MMP) inhibitory activity of a cyclam–marimastat conjugate and its metal complexes are described. The conjugate, synthesized with a copper(I)-catalyzed Huisgen 1,3-dipolar cycloaddition (“click” reaction), contains two zinc-binding groups (ZBGs). The metal complexation behavior with copper(II) and zinc(II) was investigated using UV/Vis spectrophotometry and 1H NMR spectroscopy, respectively, demonstrating that the first equivalent of the metal ion was chelated by the cyclam-triazole moiety rather than the hydroxamic acid site. Thus, the corresponding mononuclear metal–cyclam complexes were successfully prepared with one equivalent of the metal salt. Both the cyclam–marimastat conjugate and its metal complexes exhibited slightly reduced potency against MMP-1, but essentially identical inhibitory activity against MMP-3. The conjugate and its metal complexes displayed little or no cytotoxicity, further supporting their potential suitability for imaging MMP localization and activity. To the best of our knowledge, this is the first report that describes the incorporation of metal complexes into an MMP inhibitor without influencing the preexisting ZBG, and the first report of the evaluation of structures containing more than one ZBG as MMP inhibitors. PMID:24551546

  12. Potent antifungal activity of extracts and pure compound isolated from pomegranate peels and synergism with fluconazole against Candida albicans.

    PubMed

    Endo, Eliana Harue; Cortez, Diógenes Aparício Garcia; Ueda-Nakamura, Tânia; Nakamura, Celso Vataru; Dias Filho, Benedito Prado

    2010-09-01

    Activity-guided repeated fractionation of crude hydro alcoholic extract prepared from the fruit peel of Punica granatum on a silica-gel column yielded a compound that exhibited strong antifungal activity against Candida spp. Based on spectral analyses, the compound was identified as punicalagin. Punicalagin showed strong activity against Candida albicans and Candida parapsilosis, with MICs of 3.9 and 1.9 microg/ml, respectively. The combination of punicalagin and fluconazole showed a synergistic interaction. MIC for fluconazole decreased twofold when combined with the extract. The FIC index was 0.25. The synergism observed in disk-diffusion and checkerboard assays was confirmed in time-kill curves. The effect of punicalagin on the morphology and ultrastructure in treated yeast cells was examined by scanning and transmission electron microscopy. An irregular budding pattern and pseudohyphae were seen in treated yeasts. By transmission electron microscopy, treated cells showed a thickened cell wall, changes in the space between cell wall and the plasma membrane, vacuoles, and a reduction in cytoplasmic content. Since the punicalagin concentration effective in vitro is achievable in vivo, the combination of this agent with fluconazole represents an attractive prospect for the development of new management strategies for candidiasis, and should be investigated further in in vivo models. PMID:20541606

  13. Anti-inflammatory activity of cinnamon (C. zeylanicum and C. cassia) extracts - identification of E-cinnamaldehyde and o-methoxy cinnamaldehyde as the most potent bioactive compounds.

    PubMed

    Gunawardena, Dhanushka; Karunaweera, Niloo; Lee, Samiuela; van Der Kooy, Frank; Harman, David G; Raju, Ritesh; Bennett, Louise; Gyengesi, Erika; Sucher, Nikolaus J; Münch, Gerald

    2015-03-01

    Chronic inflammation is a contributing factor in many age-related diseases. In a previous study, we have shown that Sri Lankan cinnamon (C. zeylanicum) was one of the most potent anti-inflammatory foods out of 115 foods tested. However, knowledge about the exact nature of the anti-inflammatory compounds and their distribution in the two major cinnamon species used for human consumption is limited. The aim of this investigation was to determine the anti-inflammatory activity of C. zeylanicum and C. cassia and elucidate their main phytochemical compounds. When extracts were tested in LPS and IFN-γ activated RAW 264.7 macrophages, most of the anti-inflammatory activity, measured by down-regulation of nitric oxide and TNF-α production, was observed in the organic extracts. The most abundant compounds in these extracts were E-cinnamaldehyde and o-methoxycinnamaldehyde. The highest concentration of E-cinnamaldehyde was found in the DCM extract of C. zeylanicum or C. cassia (31 and 34 mg g(-1) of cinnamon, respectively). When these and other constituents were tested for their anti-inflammatory activity in RAW 264.7 and J774A.1 macrophages, the most potent compounds were E-cinnamaldehyde and o-methoxycinnamaldehyde, which exhibited IC₅₀ values for NO with RAW 264.7 cells of 55 ± 9 μM (7.3 ± 1.2 μg mL(-1)) and 35 ± 9 μM (5.7 ± 1.5 μg mL(-1)), respectively; and IC₅₀ values for TNF-α of 63 ± 9 μM (8.3 ± 1.2 μg mL(-1)) and 78 ± 16 μM (12.6 ± 2.6 μg mL(-1)), respectively. If therapeutic concentrations can be achieved in target tissues, cinnamon and its components may be useful in the treatment of age-related inflammatory conditions.

  14. Pharmacokinetics and pharmacodynamics of orally administered acetylenic tricyclic bis(cyanoenone), a highly potent Nrf2 activator with a reversible covalent mode of action

    SciTech Connect

    Kostov, Rumen V.; Knatko, Elena V.; McLaughlin, Lesley A.; Henderson, Colin J.; Zheng, Suqing; Huang, Jeffrey T.-J.; Honda, Tadashi; Dinkova-Kostova, Albena T.

    2015-09-25

    The acetylenic tricyclic bis(cyanoenone) TBE-31 is a highly potent cysteine targeting compound with a reversible covalent mode of action; its best-characterized target being Kelch-like ECH-associated protein-1 (Keap1), the cellular sensor for oxidants and electrophiles. TBE-31 reacts with cysteines of Keap1, impairing its ability to target nuclear factor-erythroid 2 p45-related factor 2 (Nrf2) for degradation. Consequently, Nrf2 accumulates and orchestrates cytoprotective gene expression. In this study we investigated the pharmacokinetic and pharmacodynamic properties of TBE-31 in C57BL/6 mice. After a single oral dose of 10 μmol/kg (∼200 nmol/animal), the concentration of TBE-31 in blood exhibited two peaks, at 22.3 nM and at 15.5 nM, 40 min and 4 h after dosing, respectively, as determined by a quantitative stable isotope dilution LC-MS/MS method. The AUC{sub 0–24h} was 195.5 h/nmol/l, the terminal elimination half-life was 10.2 h, and the k{sub el} was 0.068 h{sup −1}. To assess the pharmacodynamics of Nrf2 activation by TBE-31, we determined the enzyme activity of its prototypic target, NAD(P)H:quinone oxidoreductase 1 (NQO1) and found it elevated by 2.4- and 1.5-fold in liver and heart, respectively. Continuous feeding for 18 days with diet delivering the same daily doses of TBE-31 under conditions of concurrent treatment with the immunosuppressive agent azathioprine had a similar effect on Nrf2 activation without any indications of toxicity. Together with previous reports showing the cytoprotective effects of TBE-31 in animal models of carcinogenesis, our results demonstrate the high potency, efficacy and suitability for chronic administration of cysteine targeting reversible covalent drugs. - Highlights: • TBE-31 is a cysteine targeting compound with a reversible covalent mode of action. • After a single oral dose, the blood concentration of TBE-31 exhibits two peaks. • Oral TBE-31 is a potent activator of Nrf2-dependent enzymes in

  15. Improved total synthesis and biological evaluation of potent apratoxin S4 based anticancer agents with differential stability and further enhanced activity.

    PubMed

    Chen, Qi-Yin; Liu, Yanxia; Cai, Weijing; Luesch, Hendrik

    2014-04-10

    Apratoxins are cytotoxic natural products originally isolated from marine cyanobacteria that act by preventing cotranslational translocation early in the secretory pathway to downregulate receptor levels and inhibit growth factor secretion, leading to potent antiproliferative activity. Through rational design and total synthesis of an apratoxin A/E hybrid, apratoxin S4 (1a), we have previously improved the antitumor activity and tolerability in vivo. Compound 1a and newly designed analogues apratoxins S7-S9 (1b-d), with various degrees of methylation at C34 (1b,c) or epimeric configuration at C30 (1d), were efficiently synthesized utilizing improved procedures. Optimizations have been applied to the synthesis of key intermediate aldehyde 7 and further include the application of Leighton's silanes and modifications of Kelly's methods to induce thiazoline ring formation in other crucial steps of the apratoxin synthesis. Apratoxin S9 (1d) exhibited increased activity with subnanomolar potency. Apratoxin S8 (1c) lacks the propensity to be deactivated by dehydration and showed efficacy in a human HCT116 xenograft mouse model.

  16. Improved Total Synthesis and Biological Evaluation of Potent Apratoxin S4 Based Anticancer Agents with Differential Stability and Further Enhanced Activity

    PubMed Central

    2015-01-01

    Apratoxins are cytotoxic natural products originally isolated from marine cyanobacteria that act by preventing cotranslational translocation early in the secretory pathway to downregulate receptor levels and inhibit growth factor secretion, leading to potent antiproliferative activity. Through rational design and total synthesis of an apratoxin A/E hybrid, apratoxin S4 (1a), we have previously improved the antitumor activity and tolerability in vivo. Compound 1a and newly designed analogues apratoxins S7–S9 (1b–d), with various degrees of methylation at C34 (1b,c) or epimeric configuration at C30 (1d), were efficiently synthesized utilizing improved procedures. Optimizations have been applied to the synthesis of key intermediate aldehyde 7 and further include the application of Leighton’s silanes and modifications of Kelly’s methods to induce thiazoline ring formation in other crucial steps of the apratoxin synthesis. Apratoxin S9 (1d) exhibited increased activity with subnanomolar potency. Apratoxin S8 (1c) lacks the propensity to be deactivated by dehydration and showed efficacy in a human HCT116 xenograft mouse model. PMID:24660812

  17. Selective inhibition of EZH2 by ZLD1039 blocks H3K27methylation and leads to potent anti-tumor activity in breast cancer

    PubMed Central

    Song, Xuejiao; Gao, Tiantao; Wang, Ningyu; Feng, Qiang; You, Xinyu; Ye, Tinghong; Lei, Qian; Zhu, Yongxia; Xiong, Menghua; Xia, Yong; Yang, Fangfang; Shi, Yaojie; Wei, Yuquan; Zhang, Lidan; Yu, Luoting

    2016-01-01

    Enhancer of zeste homolog 2 (EZH2) is a candidate oncogenic driver due to its prevalent overexpression and aberrant repression of tumor suppressor genes in diverse cancers. Therefore, blocking EZH2 enzyme activity may present a valid therapeutic strategy for the treatment of cancers with EZH2 overexpression including breast cancers. Here, we described ZLD1039 a potent, highly selective, and orally bioavailable small molecule inhibitor of EZH2, which inhibited breast tumor growth and metastasis. ZLD1039 considerably inhibited EZH2 methyltransferase activity with nanomolar potency, decreased global histone-3 lysine-27 (H3K27) methylation, and reactivated silenced tumor suppressors connected to increased survival of patients with breast cancer. Comparable to conditional silencing of EZH2, its inhibition by ZLD1039 decreased cell proliferation, cell cycle arrest, and induced apoptosis. Comparably, treatment of xenograft-bearing mice with ZLD1039 led to tumor growth regression and metastasis inhibition. These data confirmed the dependency of breast cancer progression on EZH2 activity and the usefulness of ZLD1039 as a promising treatment for breast cancer. PMID:26868841

  18. The pro-apoptotic protein, Bik, exhibits potent antitumor activity that is dependent on its BH3 domain.

    PubMed

    Tong, Y; Yang, Q; Vater, C; Venkatesh, L K; Custeau, D; Chittenden, T; Chinnadurai, G; Gourdeau, H

    2001-12-01

    The Bcl-2 homology 3 (BH3) domain is present in most members of the Bcl-2 protein family and is required to confer the death-inducing properties of pro-apoptotic members, including Bax, Bak, Bad, and Bik, in cell-based assay systems. To determine whether the BH3 domain possesses a similar role in tumor tissues in vivo, we overexpressed the wild-type Bik protein and its BH3-deleted counterpart, using adenoviral technology, in chemoresistant human tumor prostate (PC-3) and colon (HT-29) cell lines growing in vitro and in vivo. Bik caused apoptosis in both PC-3 and HT-29 cells in vitro by inducing the release of cytochrome c from mitochondria to cytoplasm, resulting in the catalytic activation of caspases 9, 7, and 3 and cleavage of poly(ADP-ribose) polymerase and DNA fragmentation. When the BH3 domain was deleted from the Bik protein, no effect on mitochondrial activity or cell morphology could be observed. Furthermore, intratumoral injection of an adenovirus vector expressing the Bik gene, but not the deleted BH3 Bik gene, suppressed the growth of PC-3 and HT-29 xenografts established in nude mice. Histological examination of tumors from mice treated with the wild-type Bik adenoviral construct demonstrated cellular debris, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling positive staining, and morphological changes associated with apoptosis. In contrast, tissue sections obtained from tumors treated with the BH3-deleted Bik adenoviral construct showed no evidence of apoptosis. Thus, our results suggest that the BH3 domain is required for the antitumor activity of the Bik protein and provides a novel therapeutic approach for cancer therapy.

  19. BRAF inhibitors reverse the unique molecular signature and phenotype of hairy cell leukemia and exert potent antileukemic activity

    PubMed Central

    Pettirossi, Valentina; Santi, Alessia; Imperi, Elisa; Russo, Guido; Pucciarini, Alessandra; Bigerna, Barbara; Schiavoni, Gianluca; Fortini, Elisabetta; Spanhol-Rosseto, Ariele; Sportoletti, Paolo; Mannucci, Roberta; Martelli, Maria Paola; Klein-Hitpass, Ludger; Falini, Brunangelo

    2015-01-01

    Hairy cell leukemia (HCL) shows unique clinicopathological and biological features. HCL responds well to purine analogs but relapses are frequent and novel therapies are required. BRAF-V600E is the key driver mutation in HCL and distinguishes it from other B-cell lymphomas, including HCL-like leukemias/lymphomas (HCL-variant and splenic marginal zone lymphoma). The kinase-activating BRAF-V600E mutation also represents an ideal therapeutic target in HCL. Here, we investigated the biological and therapeutic importance of the activated BRAF–mitogen-activated protein kinase kinase (MEK)–extracellular signal-regulated kinase (ERK) pathway in HCL by exposing in vitro primary leukemic cells purified from 26 patients to clinically available BRAF (vemurafenib; dabrafenib) or MEK (trametinib) inhibitors. Results were validated in vivo in samples from vemurafenib-treated HCL patients within a phase 2 clinical trial. BRAF and MEK inhibitors caused, specifically in HCL (but not HCL-like) cells, marked MEK/ERK dephosphorylation, silencing of the BRAF-MEK-ERK pathway transcriptional output, loss of the HCL-specific gene expression signature, downregulation of the HCL markers CD25, tartrate-resistant acid phosphatase, and cyclin D1, smoothening of leukemic cells’ hairy surface, and, eventually, apoptosis. Apoptosis was partially blunted by coculture with bone marrow stromal cells antagonizing MEK-ERK dephosphorylation. This protective effect could be counteracted by combined BRAF and MEK inhibition. Our results strongly support and inform the clinical use of BRAF and MEK inhibitors in HCL. PMID:25480661

  20. Potent inhibitory effects of benzyl and p-xylidine-bis dithiocarbamate sodium salts on activities of mushroom tyrosinase.

    PubMed

    Amin, E; Saboury, A A; Mansuri-Torshizi, H; Moosavi-Movahedi, A A

    2010-04-01

    A novel monofunctional benzyldithiocarbamate, C(6)H(5)CH(2)NHCSSNa (I), and a bifunctional p-xylidine-bis(dithiocarbamate), NaSSCNHCH(2)C(6)H(4)CH(2)NHCSSNa (II), as sodium salts, were synthesized by reaction between p-xylylenediamine or benzylamine with CS(2) in the presence of NaOH. They were characterized by spectroscopic techniques such as (1)H NMR, IR, and elemental analysis. These water-soluble compounds were examined for their inhibition of both activities of mushroom tyrosinase (MT) from a commercial source of Agricus bisporus. l-3,4- Dihydroxyphenylalanine (L-DOPA) and l-tyrosine were used as natural substrates for the catecholase and cresolase enzyme reactions, respectively. Kinetic studies showed noncompetitive inhibition of I and mixed type inhibition of II on both activities of MT. The inhibition constant (K(I)) of II was smaller than that of I. Raising the temperature from 27 to 37 degrees C caused a decrease in K(I) values of I and an increase in values of II. The binding process for inhibition of I was only entropy driven, which means that the predominant interaction in the active site of the enzyme is hydrophobic; meanwhile, the electrostatic interaction can be important for the inhibition of II due to the enthalpy driven binding process. Fluorescence studies showed a decrease of emission intensity without a shift of emission maximum in the presence of different concentrations of compounds. An extrinsic fluorescence study did not show any considerable change of the tertiary structure of MT. Probably, the conformation of inhibitor-bound MT is stable and inflexible compared with uninhibited MT.

  1. Chemical synthesis of echistatin, a potent inhibitor of platelet aggregation from Echis carinatus: synthesis and biological activity of selected analogs.

    PubMed

    Garsky, V M; Lumma, P K; Freidinger, R M; Pitzenberger, S M; Randall, W C; Veber, D F; Gould, R J; Friedman, P A

    1989-06-01

    Echistatin, a polypeptide from the venom of the saw-scaled viper, Echis carinatus, containing 49 amino acids and 4 cystine bridges was synthesized by solid-phase methodology in 4% yield. In the final step, air oxidation of the octahydroderivative was found to be optimal at pH 8. The synthetic product was shown to be physically and biologically indistinguishable from native material. It inhibits fibrinogen-dependent platelet aggregation stimulated by ADP with IC50 = 3.3 x 10(-8) M and also prevents aggregation initiated by thrombin, epinephrine, collagen, or platelet-activating factor. Reduction of purified synthetic echistatin to octahydroechistatin with dithiothreitol followed by air oxidation regenerated homogeneous echistatin in quantitative yield. This highly specific refolding strongly suggests that the linear sequence of octahydroechistatin contains all of the information that is required for the proper folding of the peptide. The sequence Arg24-Gly-Asp of echistatin occurs also in adhesive glycoproteins that bind to the platelet fibrinogen receptor--a heterodimeric complex composed of glycoproteins IIb and IIIa. In an effort to evaluate the role of this putative binding site we have synthesized analogs of echistatin with substitution of Arg-24. Replacement with ornithine-24 (Orn-24) resulted in an analog having a platelet aggregation inhibitory activity with IC50 = 1.05 x 10(-7) M. Substitution with Ala-24 gave IC50 = 6.1 x 10(-7) M. The inhibitory activity of the corresponding short sequence analogs Arg-Gly-Asp-Phe (IC50 = 6 x 10(-6) M), Orn-Gly-Asp-Phe (IC50 = 1.3 x 10(-4) M), and Ala-Gly-Asp-Phe (IC50 = 5.0 x 10(-4) M) was also determined. These results suggest that arginine plays a more important role in the binding of the tetrapeptide than in that of echistatin. PMID:2726764

  2. Two new neolignans from Patrinia scabra with potent cytotoxic activity against HeLa and MNK-45 cells.

    PubMed

    Di, Lei; Yan, Guo-Qing; Wang, Ling-Yu; Ma, Wei; Wang, Kai-Jin; Li, Ning

    2013-10-01

    Two new neolignans, patrineolignan A (1) and patrineolignan B (2), together with seven known lignans, were isolated from the 90 % aqueous EtOH extract of the roots of Patrinia scabra. Their structures were elucidated on the basis of spectroscopic data (HRESIMS, IR, 1D and 2D NMR) and comparison with literature data. The two new neolignans were evaluated in vitro for cytotoxic properties against human cervical carcinoma HeLa cell line and gastric carcinoma MNK-45 cell line using the microculture tetrazolium assay, and both 1 and 2 exhibited strongly cytotoxic activity against the two tumor cell lines. PMID:23737105

  3. M. tuberculosis induces potent activation of IDO-1, but this is not essential for the immunological control of infection.

    PubMed

    Blumenthal, Antje; Nagalingam, Gayathri; Huch, Jennifer H; Walker, Lara; Guillemin, Gilles J; Smythe, George A; Ehrt, Sabine; Britton, Warwick J; Saunders, Bernadette M

    2012-01-01

    Indoleamine 2,3-dioxygenesae-1 (IDO-1) catalyses the initial, rate-limiting step in tryptophan metabolism, thereby regulating tryptophan availability and the formation of downstream metabolites, including picolinic and quinolinic acid. We found that Mycobacterium tuberculosis infection induced marked upregulation of IDO-1 expression in both human and murine macrophages in vitro and in the lungs of mice following aerosol challenge with M. tuberculosis. The absence of IDO-1 in dendritic cells enhanced the activation of mycobacteria-specific T cells in vitro. Interestingly, IDO-1-deficiency during M. tuberculosis infection in mice was not associated with altered mycobacteria-specific T cell responses in vivo. The bacterial burden of infected organs, pulmonary inflammatory responses, and survival were also comparable in M. tuberculosis-infected IDO-1 deficient and wild type animals. Tryptophan is metabolised into either picolinic acid or quinolinic acid, but only picolinic acid inhibited the growth of M. tuberculosis in vitro. By contrast macrophages infected with pathogenic mycobacteria, produced quinolinic, rather than picolinic acid, which did not reduce M. tuberculosis growth in vitro. Therefore, although M. tuberculosis induces robust expression of IDO-1 and activation of tryptophan metabolism, IDO-1-deficiency fails to impact on the immune control and the outcome of the infection in the mouse model of tuberculosis.

  4. A novel PI3K inhibitor PIK-C98 displays potent preclinical activity against multiple myeloma

    PubMed Central

    Yu, Yang; Qi, Huixin; Han, Kunkun; Tang, Juan; Zhang, Zubin; Zeng, Yuanying; Cao, Biyin; Qiao, Chunhua; Zhang, Hongjian; Hou, Tingjun; Mao, Xinliang

    2015-01-01

    Recent clinical trials have demonstrated targeting PI3K pathway is a promising strategy for the treatment of blood cancers. To identify novel PI3K inhibitors, we performed a high throughput virtual screen and identified several novel small molecule compounds, including PIK-C98 (C98). The cell-free enzymatic studies showed that C98 inhibited all class I PI3Ks at nano- or low micromolar concentrations but had no effects on AKT or mTOR activity. Molecular docking analysis revealed that C98 interfered with the ATP-binding pockets of PI3Ks by forming H-bonds and arene-H interactions with specific amino acid residues. The cellular assays demonstrated that C98 specifically inhibited PI3K/AKT/mTOR signaling pathway, but had no effects on other kinases and proteins including IGF-1R, ERK, p38, c-Src, PTEN, and STAT3. Inhibition of PI3K by C98 led to myeloma cell apoptosis. Furthermore, oral administration of C98 delayed tumor growth in two independent human myeloma xenograft models in nude mice but did not show overt toxicity. Pharmacokinetic analyses showed that C98 was well penetrated into myeloma tumors. Therefore, through a high throughput virtual screen we identified a novel PI3K inhibitor that is orally active against multiple myeloma with great potential for further development. PMID:25474140

  5. Folate-associated lipoplexes mediate efficient gene delivery and potent antitumoral activity in vitro and in vivo.

    PubMed

    Duarte, Sónia; Faneca, Henrique; Lima, Maria C Pedroso de

    2012-02-28

    The lack of suitable vectors for efficient nucleic acid delivery into target cells represents a major hurdle for the successful application of gene therapy. Cationic liposomes exhibit attractive features for gene delivery, but their efficacy is still unsatisfactory, particularly for in vivo applications, which justifies the drive to further improve their performance by developing novel and efficient formulations. In the present study, we generated a new formulation of lipoplexes through electrostatic association of folate (FA) to 1-palmitoyl-2-oleoyl-sn-glycero-3-ethylphosphocholine (EPOPC):cholesterol (Chol) liposomes, prepared at different lipid/DNA charge ratios, and explored their potential to mediate gene delivery. The optimal FA-lipoplex formulation was evaluated for its efficacy to mediate antitumoral activity upon application of HSV-tk suicide gene therapy, both in vitro and in an animal model of oral cancer. Our results demonstrate that FA-EPOPC:Chol/DNA lipoplexes were able to promote a great enhancement of transfection and high in vitro antitumoral activity compared to plain lipoplexes in two different cancer cell lines. Most importantly, a considerable reduction of tumor growth was achieved with the developed FA-lipoplexes as compared to that observed for control FA-lipoplexes or plain lipoplexes. Overall, our study shows that FA-EPOPC:Chol/DNA lipoplexes constitute a promising system for the successful application of suicide gene therapy aiming at treating solid tumors. PMID:22209825

  6. Potent antimicrobial and antibiofilm activities of bacteriogenically synthesized gold-silver nanoparticles against pathogenic bacteria and their physiochemical characterizations.

    PubMed

    Ramasamy, Mohankandhasamy; Lee, Jin-Hyung; Lee, Jintae

    2016-09-01

    The objective of this study was to develop a bimetallic nanoparticle with enhanced antibacterial activity that would improve the therapeutic efficacy against bacterial biofilms. Bimetallic gold-silver nanoparticles were bacteriogenically synthesized using γ-proteobacterium, Shewanella oneidensis MR-1. The antibacterial activities of gold-silver nanoparticles were assessed on the planktonic and biofilm phases of individual and mixed multi-cultures of pathogenic Gram negative (Escherichia coli and Pseudomonas aeruginosa) and Gram positive bacteria (Enterococcus faecalis and Staphylococcus aureus), respectively. The minimum inhibitory concentration of gold-silver nanoparticles was 30-50 µM than that of other nanoparticles (>100 µM) for the tested bacteria. Interestingly, gold-silver nanoparticles were more effective in inhibiting bacterial biofilm formation at 10 µM concentration. Both scanning and transmission electron microscopy results further accounted the impact of gold-silver nanoparticles on biocompatibility and bactericidal effect that the small size and bio-organic materials covering on gold-silver nanoparticles improves the internalization and thus caused bacterial inactivation. Thus, bacteriogenically synthesized gold-silver nanoparticles appear to be a promising nanoantibiotic for overcoming the bacterial resistance in the established bacterial biofilms. PMID:27117745

  7. MmTX1 and MmTX2 from coral snake venom potently modulate GABAA receptor activity.

    PubMed

    Rosso, Jean-Pierre; Schwarz, Jürgen R; Diaz-Bustamante, Marcelo; Céard, Brigitte; Gutiérrez, José M; Kneussel, Matthias; Pongs, Olaf; Bosmans, Frank; Bougis, Pierre E

    2015-02-24

    GABAA receptors shape synaptic transmission by modulating Cl(-) conductance across the cell membrane. Remarkably, animal toxins that specifically target GABAA receptors have not been identified. Here, we report the discovery of micrurotoxin1 (MmTX1) and MmTX2, two toxins present in Costa Rican coral snake venom that tightly bind to GABAA receptors at subnanomolar concentrations. Studies with recombinant and synthetic toxin variants on hippocampal neurons and cells expressing common receptor compositions suggest that MmTX1 and MmTX2 allosterically increase GABAA receptor susceptibility to agonist, thereby potentiating receptor opening as well as desensitization, possibly by interacting with the α(+)/β(-) interface. Moreover, hippocampal neuron excitability measurements reveal toxin-induced transitory network inhibition, followed by an increase in spontaneous activity. In concert, toxin injections into mouse brain result in reduced basal activity between intense seizures. Altogether, we characterized two animal toxins that enhance GABAA receptor sensitivity to agonist, thereby establishing a previously unidentified class of tools to study this receptor family.

  8. MmTX1 and MmTX2 from coral snake venom potently modulate GABAA receptor activity

    PubMed Central

    Rosso, Jean-Pierre; Schwarz, Jürgen R.; Diaz-Bustamante, Marcelo; Céard, Brigitte; Gutiérrez, José M.; Kneussel, Matthias; Pongs, Olaf; Bosmans, Frank; Bougis, Pierre E.

    2015-01-01

    GABAA receptors shape synaptic transmission by modulating Cl− conductance across the cell membrane. Remarkably, animal toxins that specifically target GABAA receptors have not been identified. Here, we report the discovery of micrurotoxin1 (MmTX1) and MmTX2, two toxins present in Costa Rican coral snake venom that tightly bind to GABAA receptors at subnanomolar concentrations. Studies with recombinant and synthetic toxin variants on hippocampal neurons and cells expressing common receptor compositions suggest that MmTX1 and MmTX2 allosterically increase GABAA receptor susceptibility to agonist, thereby potentiating receptor opening as well as desensitization, possibly by interacting with the α+/β− interface. Moreover, hippocampal neuron excitability measurements reveal toxin-induced transitory network inhibition, followed by an increase in spontaneous activity. In concert, toxin injections into mouse brain result in reduced basal activity between intense seizures. Altogether, we characterized two animal toxins that enhance GABAA receptor sensitivity to agonist, thereby establishing a previously unidentified class of tools to study this receptor family. PMID:25675485

  9. Design, Synthesis and Structure-Activity Relationship Studies of Novel Survivin Inhibitors with Potent Anti-Proliferative Properties

    PubMed Central

    Xiao, Min; Wang, Jin; Lin, Zongtao; Lu, Yan; Li, Zhenmei; White, Stephen W.; Miller, Duane D.; Li, Wei

    2015-01-01

    The anti-apoptotic protein survivin is highly expressed in most human cancer cells, but has very low expression in normal differentiated cells. Thus survivin is considered as an attractive cancer drug target. Herein we report the design and synthesis of a series of novel survivin inhibitors based on the oxyquinoline scaffold from our recently identified hit compound UC-112. These new analogs were tested against a panel of cancer cell lines including one with multidrug-resistant phenotype. Eight of these new UC-112 analogs showed IC50 values in the nanomole range in anti-proliferative assays. The best three compounds among them along with UC-112 were submitted for NCI-60 cancer cell line screening. The results indicated that structural modification from UC-112 to our best compound 4g has improved activity by four folds (2.2 μM for UC-112 vs. 0.5 μM for 4g, average GI50 values over all cancer cell lines in the NCI-60 panel).Western blot analyses demonstrated the new compounds maintained high selectivity for survivin inhibition over other members in the inhibition of apoptosis protein family. When tested in an A375 human melanoma xenograft model, the most active compound 4g effectively suppressed tumor growth and strongly induced cancer cell apoptosis in tumor tissues. This novel scaffold is promising for the development of selective survivin inhibitors as potential anticancer agents. PMID:26070194

  10. Novel Indole-2-Carboxamide Compounds Are Potent Broad-Spectrum Antivirals Active against Western Equine Encephalitis Virus In Vivo

    PubMed Central

    Delekta, Phillip C.; Dobry, Craig J.; Sindac, Janice A.; Barraza, Scott J.; Blakely, Pennelope K.; Xiang, Jianming; Kirchhoff, Paul D.; Keep, Richard F.; Irani, David N.; Larsen, Scott D.

    2014-01-01

    ABSTRACT Neurotropic alphaviruses, including western, eastern, and Venezuelan equine encephalitis viruses, cause serious and potentially fatal central nervous system infections in humans for which no currently approved therapies exist. We previously identified a series of thieno[3,2-b]pyrrole derivatives as novel inhibitors of neurotropic alphavirus replication, using a cell-based phenotypic assay (W. Peng et al., J. Infect. Dis. 199:950–957, 2009, doi:http://dx.doi.org/10.1086/597275), and subsequently developed second- and third-generation indole-2-carboxamide derivatives with improved potency, solubility, and metabolic stability (J. A. Sindac et al., J. Med. Chem. 55:3535–3545, 2012, doi:http://dx.doi.org/10.1021/jm300214e; J. A. Sindac et al., J. Med. Chem. 56:9222–9241, 2013, http://dx.doi.org/10.1021/jm401330r). In this report, we describe the antiviral activity of the most promising third-generation lead compound, CCG205432, and closely related analogs CCG206381 and CCG209023. These compounds have half-maximal inhibitory concentrations of ∼1 μM and selectivity indices of >100 in cell-based assays using western equine encephalitis virus replicons. Furthermore, CCG205432 retains similar potency against fully infectious virus in cultured human neuronal cells. These compounds show broad inhibitory activity against a range of RNA viruses in culture, including members of the Togaviridae, Bunyaviridae, Picornaviridae, and Paramyxoviridae families. Although their exact molecular target remains unknown, mechanism-of-action studies reveal that these novel indole-based compounds target a host factor that modulates cap-dependent translation. Finally, we demonstrate that both CCG205432 and CCG209023 dampen clinical disease severity and enhance survival of mice given a lethal western equine encephalitis virus challenge. These studies demonstrate that indole-2-carboxamide compounds are viable candidates for continued preclinical development as inhibitors of

  11. Novel indole-2-carboxamide compounds are potent broad-spectrum antivirals active against western equine encephalitis virus in vivo.

    PubMed

    Delekta, Phillip C; Dobry, Craig J; Sindac, Janice A; Barraza, Scott J; Blakely, Pennelope K; Xiang, Jianming; Kirchhoff, Paul D; Keep, Richard F; Irani, David N; Larsen, Scott D; Miller, David J

    2014-10-01

    Neurotropic alphaviruses, including western, eastern, and Venezuelan equine encephalitis viruses, cause serious and potentially fatal central nervous system infections in humans for which no currently approved therapies exist. We previously identified a series of thieno[3,2-b]pyrrole derivatives as novel inhibitors of neurotropic alphavirus replication, using a cell-based phenotypic assay (W. Peng et al., J. Infect. Dis. 199:950-957, 2009, doi:http://dx.doi.org/10.1086/597275), and subsequently developed second- and third-generation indole-2-carboxamide derivatives with improved potency, solubility, and metabolic stability (J. A. Sindac et al., J. Med. Chem. 55:3535-3545, 2012, doi:http://dx.doi.org/10.1021/jm300214e; J. A. Sindac et al., J. Med. Chem. 56:9222-9241, 2013, http://dx.doi.org/10.1021/jm401330r). In this report, we describe the antiviral activity of the most promising third-generation lead compound, CCG205432, and closely related analogs CCG206381 and CCG209023. These compounds have half-maximal inhibitory concentrations of ∼1 μM and selectivity indices of >100 in cell-based assays using western equine encephalitis virus replicons. Furthermore, CCG205432 retains similar potency against fully infectious virus in cultured human neuronal cells. These compounds show broad inhibitory activity against a range of RNA viruses in culture, including members of the Togaviridae, Bunyaviridae, Picornaviridae, and Paramyxoviridae families. Although their exact molecular target remains unknown, mechanism-of-action studies reveal that these novel indole-based compounds target a host factor that modulates cap-dependent translation. Finally, we demonstrate that both CCG205432 and CCG209023 dampen clinical disease severity and enhance survival of mice given a lethal western equine encephalitis virus challenge. These studies demonstrate that indole-2-carboxamide compounds are viable candidates for continued preclinical development as inhibitors of neurotropic

  12. The riluzole derivative 2-amino-6-trifluoromethylthio-benzothiazole (SKA-19), a mixed KCa2 activator and NaV blocker, is a potent novel anticonvulsant.

    PubMed

    Coleman, Nichole; Nguyen, Hai M; Cao, Zhengyu; Brown, Brandon M; Jenkins, David Paul; Zolkowska, Dorota; Chen, Yi-Je; Tanaka, Brian S; Goldin, Alan L; Rogawski, Michael A; Pessah, Isaac N; Wulff, Heike

    2015-01-01

    Inhibitors of voltage-gated sodium channels (Na(v)) have been used as anticonvulsants since the 1940s, while potassium channel activators have only been investigated more recently. We here describe the discovery of 2-amino-6-trifluoromethylthio-benzothiazole (SKA-19), a thioanalog of riluzole, as a potent, novel anticonvulsant, which combines the two mechanisms. SKA-19 is a use-dependent NaV channel blocker and an activator of small-conductance Ca(2+)-activated K(+) channels. SKA-19 reduces action potential firing and increases medium afterhyperpolarization in CA1 pyramidal neurons in hippocampal slices. SKA-19 is orally bioavailable and shows activity in a broad range of rodent seizure models. SKA-19 protects against maximal electroshock-induced seizures in both rats (ED50 1.6 mg/kg i.p.; 2.3 mg/kg p.o.) and mice (ED50 4.3 mg/kg p.o.), and is also effective in the 6-Hz model in mice (ED50 12.2 mg/kg), Frings audiogenic seizure-susceptible mice (ED50 2.2 mg/kg), and the hippocampal kindled rat model of complex partial seizures (ED50 5.5 mg/kg). Toxicity tests for abnormal neurological status revealed a therapeutic index (TD50/ED50) of 6-9 following intraperitoneal and of 33 following oral administration. SKA-19 further reduced acute pain in the formalin pain model and raised allodynic threshold in a sciatic nerve ligation model. The anticonvulsant profile of SKA-19 is comparable to riluzole, which similarly affects Na(V) and KCa2 channels, except that SKA-19 has a ~4-fold greater duration of action owing to more prolonged brain levels. Based on these findings we propose that compounds combining KCa2 channel-activating and Na(v) channel-blocking activity exert broad-spectrum anticonvulsant and analgesic effects.

  13. The potent Cdc7-Dbf4 (DDK) kinase inhibitor XL413 has limited activity in many cancer cell lines and discovery of potential new DDK inhibitor scaffolds.

    PubMed

    Sasi, Nanda Kumar; Tiwari, Kanchan; Soon, Fen-Fen; Bonte, Dorine; Wang, Tong; Melcher, Karsten; Xu, H Eric; Weinreich, Michael

    2014-01-01

    Cdc7-Dbf4 kinase or DDK (Dbf4-dependent kinase) is required to initiate DNA replication by phosphorylating and activating the replicative Mcm2-7 DNA helicase. DDK is overexpressed in many tumor cells and is an emerging chemotherapeutic target since DDK inhibition causes apoptosis of diverse cancer cell types but not of normal cells. PHA-767491 and XL413 are among a number of potent DDK inhibitors with low nanomolar IC50 values against the purified kinase. Although XL413 is highly selective for DDK, its activity has not been extensively characterized on cell lines. We measured anti-proliferative and apoptotic effects of XL413 on a panel of tumor cell lines compared to PHA-767491, whose activity is well characterized. Both compounds were effective biochemical DDK inhibitors but surprisingly, their activities in cell lines were highly divergent. Unlike PHA-767491, XL413 had significant anti-proliferative activity against only one of the ten cell lines tested. Since XL413 did not effectively inhibit DDK in multiple cell lines, this compound likely has limited bioavailability. To identify potential leads for additional DDK inhibitors, we also tested the cross-reactivity of ∼400 known kinase inhibitors against DDK using a DDK thermal stability shift assay (TSA). We identified 11 compounds that significantly stabilized DDK. Several inhibited DDK with comparable potency to PHA-767491, including Chk1 and PKR kinase inhibitors, but had divergent chemical scaffolds from known DDK inhibitors. Taken together, these data show that several well-known kinase inhibitors cross-react with DDK and also highlight the opportunity to design additional specific, biologically active DDK inhibitors for use as chemotherapeutic agents.

  14. The Potent Cdc7-Dbf4 (DDK) Kinase Inhibitor XL413 Has Limited Activity in Many Cancer Cell Lines and Discovery of Potential New DDK Inhibitor Scaffolds

    PubMed Central

    Sasi, Nanda Kumar; Tiwari, Kanchan; Soon, Fen-Fen; Bonte, Dorine; Wang, Tong; Melcher, Karsten; Xu, H. Eric; Weinreich, Michael

    2014-01-01

    Cdc7-Dbf4 kinase or DDK (Dbf4-dependent kinase) is required to initiate DNA replication by phosphorylating and activating the replicative Mcm2-7 DNA helicase. DDK is overexpressed in many tumor cells and is an emerging chemotherapeutic target since DDK inhibition causes apoptosis of diverse cancer cell types but not of normal cells. PHA-767491 and XL413 are among a number of potent DDK inhibitors with low nanomolar IC50 values against the purified kinase. Although XL413 is highly selective for DDK, its activity has not been extensively characterized on cell lines. We measured anti-proliferative and apoptotic effects of XL413 on a panel of tumor cell lines compared to PHA-767491, whose activity is well characterized. Both compounds were effective biochemical DDK inhibitors but surprisingly, their activities in cell lines were highly divergent. Unlike PHA-767491, XL413 had significant anti-proliferative activity against only one of the ten cell lines tested. Since XL413 did not effectively inhibit DDK in multiple cell lines, this compound likely has limited bioavailability. To identify potential leads for additional DDK inhibitors, we also tested the cross-reactivity of ∼400 known kinase inhibitors against DDK using a DDK thermal stability shift assay (TSA). We identified 11 compounds that significantly stabilized DDK. Several inhibited DDK with comparable potency to PHA-767491, including Chk1 and PKR kinase inhibitors, but had divergent chemical scaffolds from known DDK inhibitors. Taken together, these data show that several well-known kinase inhibitors cross-react with DDK and also highlight the opportunity to design additional specific, biologically active DDK inhibitors for use as chemotherapeutic agents. PMID:25412417

  15. Cholera toxin, a potent inducer of epidermal hyperplasia but with no tumor promoting activity in mouse skin carcinogenesis

    SciTech Connect

    Kuroki, T.; Chida, K.; Munakata, K.; Murakami, Y.

    1986-05-29

    Intracutaneous injection of cholera toxin into mice induced epidermal hyperplasia to a greater extent than 12-O-tetra-decanoylphorbol-13-acetate. It also induced adenylate cyclase and through weakly, ornithine decarboxylase of the epidermis. Cholera toxin, however, showed no tumor promoting activity in mouse skin carcinogenesis. In the single stage promotion, cholera toxin (50 ng) was injected once a week for 10 weeks into the skin of SENCAR mice initiated with 25 ..mu..g 7,12-dimethyl-benz(a)anthracene, but no tumors developed. In the two-stage promotion test, cholera toxin (10-100 ng) was injected for one or two weeks into the initiated skin and then mezerein (4 ..mu..g) was applied twice a week for 18 weeks, but the toxin did not increase incidence or numbers of papillomas.

  16. Selectivity Profiling and Biological Activity of Novel β-Carbolines as Potent and Selective DYRK1 Kinase Inhibitors

    PubMed Central

    Rüben, Katharina; Wurzlbauer, Anne; Walte, Agnes; Sippl, Wolfgang; Bracher, Franz; Becker, Walter

    2015-01-01

    DYRK1A is a pleiotropic protein kinase with diverse functions in cellular regulation, including cell cycle control, neuronal differentiation, and synaptic transmission. Enhanced activity and overexpression of DYRK1A have been linked to altered brain development and function in Down syndrome and neurodegenerative diseases such as Alzheimer’s disease. The β-carboline alkaloid harmine is a high affinity inhibitor of DYRK1A but suffers from the drawback of inhibiting monoamine oxidase A (MAO-A) with even higher potency. Here we characterized a series of novel harmine analogs with minimal or absent MAO-A inhibitory activity. We identified several inhibitors with submicromolar potencies for DYRK1A and selectivity for DYRK1A and DYRK1B over the related kinases DYRK2 and HIPK2. An optimized inhibitor, AnnH75, inhibited CLK1, CLK4, and haspin/GSG2 as the only off-targets in a panel of 300 protein kinases. In cellular assays, AnnH75 dose-dependently reduced the phosphorylation of three known DYRK1A substrates (SF3B1, SEPT4, and tau) without negative effects on cell viability. AnnH75 inhibited the cotranslational tyrosine autophosphorylation of DYRK1A and threonine phosphorylation of an exogenous substrate protein with similar potency. In conclusion, we have characterized an optimized β-carboline inhibitor as a highly selective chemical probe that complies with desirable properties of drug-like molecules and is suitable to interrogate the function of DYRK1A in biological studies. PMID:26192590

  17. Selectivity Profiling and Biological Activity of Novel β-Carbolines as Potent and Selective DYRK1 Kinase Inhibitors.

    PubMed

    Rüben, Katharina; Wurzlbauer, Anne; Walte, Agnes; Sippl, Wolfgang; Bracher, Franz; Becker, Walter

    2015-01-01

    DYRK1A is a pleiotropic protein kinase with diverse functions in cellular regulation, including cell cycle control, neuronal differentiation, and synaptic transmission. Enhanced activity and overexpression of DYRK1A have been linked to altered brain development and function in Down syndrome and neurodegenerative diseases such as Alzheimer's disease. The β-carboline alkaloid harmine is a high affinity inhibitor of DYRK1A but suffers from the drawback of inhibiting monoamine oxidase A (MAO-A) with even higher potency. Here we characterized a series of novel harmine analogs with minimal or absent MAO-A inhibitory activity. We identified several inhibitors with submicromolar potencies for DYRK1A and selectivity for DYRK1A and DYRK1B over the related kinases DYRK2 and HIPK2. An optimized inhibitor, AnnH75, inhibited CLK1, CLK4, and haspin/GSG2 as the only off-targets in a panel of 300 protein kinases. In cellular assays, AnnH75 dose-dependently reduced the phosphorylation of three known DYRK1A substrates (SF3B1, SEPT4, and tau) without negative effects on cell viability. AnnH75 inhibited the cotranslational tyrosine autophosphorylation of DYRK1A and threonine phosphorylation of an exogenous substrate protein with similar potency. In conclusion, we have characterized an optimized β-carboline inhibitor as a highly selective chemical probe that complies with desirable properties of drug-like molecules and is suitable to interrogate the function of DYRK1A in biological studies. PMID:26192590

  18. Human Genetic Relevance and Potent Antitumor Activity of Heat Shock Protein 90 Inhibition in Canine Lung Adenocarcinoma Cell Lines

    PubMed Central

    Clemente-Vicario, Francisco; Alvarez, Carlos E.; Rowell, Jennie L.; Roy, Satavisha; London, Cheryl A.; Kisseberth, William C.; Lorch, Gwendolen

    2015-01-01

    Background It has been an open question how similar human and canine lung cancers are. This has major implications in availability of human treatments for dogs and in establishing translational models to test new therapies in pet dogs. The prognosis for canine advanced lung cancer is poor and new treatments are needed. Heat shock protein 90 (HSP90) is an ATPase-dependent molecular chaperone ubiquitously expressed in eukaryotic cells. HSP90 is essential for posttranslational conformational maturation and stability of client proteins including protein kinases and transcription factors, many of which are important for the proliferation and survival of cancer cells. We investigated the activity of STA-1474, a HSP90 inhibitor, in two canine lung cancer cell lines, BACA and CLAC. Results Comparative genomic hybridization analysis of both cell lines revealed genetic relevance to human non-small cell lung cancer. STA-1474 inhibited growth and induced apoptosis of both cell lines in a dose- and time-dependent manner. The ICs50 after 72 h treatment with STA-1474 were 0.08 and 0.11 μM for BACA and CLAC, respectively. When grown as spheroids, the IC50 of STA-1474 for BACA cells was approximately two-fold higher than when grown as a monolayer (0.348 μM vs. 0.168 μM), whereas CLAC spheroids were relatively drug resistant. Treatment of tumor-stromal fibroblasts with STA-1474 resulted in a dose-dependent decrease in their relative cell viability with a low IC50 of 0.28 μM. Conclusions Here we first established that lung adenocarcinoma in people and dogs are genetically and biochemically similar. STA1474 demonstrated biological activity in both canine lung cancer cell lines and tumor-stromal fibroblasts. As significant decreases in relative cell viability can be achieved with nanomolar concentrations of STA-1474, investigation into the clinical efficacy of this drug in canine lung cancer patients is warranted. PMID:26560147

  19. Potent Antiviral Activities of the Direct-Acting Antivirals ABT-493 and ABT-530 with Three-Day Monotherapy for Hepatitis C Virus Genotype 1 Infection

    PubMed Central

    O'Riordan, William D.; Asatryan, Armen; Freilich, Bradley L.; Box, Terry D.; Overcash, J. Scott; Lovell, Sandra; Ng, Teresa I.; Liu, Wei; Campbell, Andrew; Lin, Chih-Wei; Yao, Betty; Kort, Jens

    2015-01-01

    ABT-493 is a hepatitis C virus (HCV) nonstructural (NS) protein 3/4A protease inhibitor, and ABT-530 is an HCV NS5A inhibitor. These direct-acting antivirals (DAAs) demonstrated potent antiviral activity against major HCV genotypes and high barriers to resistance in vitro. In this open-label dose-ranging trial, antiviral activity and safety were assessed during 3 days of monotherapy with ABT-493 or ABT-530 in treatment-naive adults with HCV genotype 1 infection, with or without compensated cirrhosis. The presence of baseline resistance-associated variants (RAVs) was also evaluated. The mean maximal decreases in HCV RNA levels from baseline were approximately 4 log10 IU/ml for all ABT-493 doses ranging from 100 mg to 700 mg and for ABT-530 doses of ≥40 mg. There were no meaningful differences in viral load declines for patients with versus without compensated cirrhosis. Twenty-four (50%) of the baseline samples from patients treated with ABT-493 had RAVs to NS3/4A protease inhibitors. Among 40 patients treated with ABT-530, 6 (15%) carried baseline RAVs to NS5A inhibitors. Viral load declines in patients with single baseline NS5A RAVs were similar to those in patients without RAVs. One patient harbored baseline RAVs at 3 NS5A positions and appeared to have a slightly less robust viral load decline on day 3 of monotherapy. No serious or grade 3 (severe) or higher adverse events and no clinically relevant laboratory abnormalities were observed with either compound. ABT-493 and ABT-530 demonstrated potent antiviral activity and acceptable safety during 3-day monotherapy in patients with HCV genotype 1 infection, with or without compensated cirrhosis. Based on these results, phase II studies assessing the combination of these DAAs for the treatment of chronic HCV infection in patients with or without compensated cirrhosis have been initiated. (This study has been registered at ClinicalTrials.gov under registration no. NCT01995071.) PMID:26711747

  20. Intrastrain Comparison of the Chemical Composition and Antioxidant Activity of an Edible Mushroom, Pleurotus giganteus, and Its Potent Neuritogenic Properties

    PubMed Central

    David, Pamela; Tan, Yee-Shin; Wong, Kah-Hui; Kuppusamy, Umah Rani; Sabaratnam, Vikineswary

    2014-01-01

    Two strains of Pleurotus giganteus (commercial and wild) were tested for their ability to induce neurite outgrowth in rat pheochromocytoma (PC12) and mouse neuroblastoma-2a (N2a) cells. Treatment with the mushroom extracts resulted in neuronal differentiation and neuronal elongation, but not nerve growth factor (NGF) production. Linoleic acid (4.5–5.0%, w/w) which is a major fatty acid present in the ethanol extract promoted NGF biosynthesis when augmented with low concentration of NGF (5 ng/mL). The two strains of mushroom were found to be high in protein (154–192 g kg−1), total polysaccharides, phenolics, and flavonoids as well as vitamins B1, B2, and B3. The total phenolics present in the mushroom extracts were positively correlated to the antioxidant activity (free radical scavenging, ferric reducing power, and lipid peroxidation inhibition). To conclude, P. giganteus could potentially be used in well-balanced diet and as a source of dietary antioxidant to promote neuronal health. PMID:25121118

  1. Enhanced activity of carbosilane dendrimers against HIV when combined with reverse transcriptase inhibitor drugs: searching for more potent microbicides

    PubMed Central

    Vacas-Córdoba, Enrique; Galán, Marta; de la Mata, Francisco J; Gómez, Rafael; Pion, Marjorie; Muñoz-Fernández, M Ángeles

    2014-01-01

    Self-administered topical microbicides or oral preexposure prophylaxis could be very helpful tools for all risk groups to decrease the human immunodeficiency virus (HIV)-1 infection rates. Up until now, antiretrovirals (ARVs) have been the most advanced microbicide candidates. Nevertheless, the majority of clinical trials has failed in HIV-1 patients. Nanotechnology offers suitable approaches to develop novel antiviral agents. Thereby, new nanosystems, such as carbosilane dendrimers, have been shown to be safe and effective compounds against HIV with great potential as topical microbicides. In addition, because most of the attempts to develop effective topical microbicides were unsuccessful, combinatorial strategies could be a valid approach when designing new microbicides. We evaluated various combinations of anionic carbosilane dendrimers with sulfated (G3-S16) and naphthyl sulfonated (G2-NF16) ended groups with different ARVs against HIV-1 infection. The G3-S16 and G2-NF16 dendrimers showed a synergistic or additive activity profile with zidovudine, efavirenz, and tenofovir in the majority of the combinations tested against the X4 and R5 tropic HIV-1 in cell lines, as well as in human primary cells. Therefore, the combination of ARVs and polyanionic carbosilane dendrimers enhances the antiviral potency of the individual compounds, and our findings support further clinical research on combinational approaches as potential microbicides to block the sexual transmission of HIV-1. PMID:25114528

  2. Molecular recognition of CYP26A1 binding pockets and structure-activity relationship studies for design of potent and selective retinoic acid metabolism blocking agents.

    PubMed

    Sun, Bin; Song, Shuai; Hao, Chen-Zhou; Huang, Wan-Xu; Liu, Chun-Chi; Xie, Hong-Lei; Lin, Bin; Cheng, Mao-Sheng; Zhao, Dong-Mei

    2015-03-01

    All-trans-retinoic acid (ATRA), the biologically most active metabolite of vitamin A, plays a major role in the regulation of cellular differentiation and proliferation, and it is also an important pharmacological agent particularly used in the treatment of cancer, skin, neurodegenerative and autoimmune diseases. However, ATRA is very easy to be metabolized into 4-hydroxyl-RA in vivo by CYP26A1, an inducible cytochrome P450 enzyme, eventually into more polar metabolites. Therefore, it is vital to develop specific retinoic acid metabolism blocking agents (RAMBAs) to inhibit the metabolic enzyme CYP26A1 in the treatment of relevant diseases aforementioned. In this study, CYP26A1 and its interactions with retinoic acid-competitive metabolism blocking agents were investigated by a combined ligand- and structure-based approach. First, since the crystal structure of CYP26A1 protein has not been determined, we constructed the 3D structure of CYP26A1 using homology modeling. In order to achieve a deeper insight into the mode of action of RAMBAs in the active site, the molecular superimposition model and the common feature pharmacophore model were constructed, and molecular docking was performed. The molecular superimposition model is composed of three features: the main chain groups, side chain groups, and azole groups. The common feature pharmacophore model consists of five chemical features: four hydrophobic groups and one hydrogen acceptor (HHHHA). The results of molecular docking show that the characteristic groups of RAMBAs were mapped into three different active pockets, respectively. A structure-activity relationship (SAR) was obtained by a combination of the molecular superimposition and docking results with the pharmacophore model. This study gives more insight into the interaction model inside the CYP26A1 active site and provides guidance for the design of more potent and possibly more selective RAMBAs. PMID:25541526

  3. Molecular recognition of CYP26A1 binding pockets and structure-activity relationship studies for design of potent and selective retinoic acid metabolism blocking agents.

    PubMed

    Sun, Bin; Song, Shuai; Hao, Chen-Zhou; Huang, Wan-Xu; Liu, Chun-Chi; Xie, Hong-Lei; Lin, Bin; Cheng, Mao-Sheng; Zhao, Dong-Mei

    2015-03-01

    All-trans-retinoic acid (ATRA), the biologically most active metabolite of vitamin A, plays a major role in the regulation of cellular differentiation and proliferation, and it is also an important pharmacological agent particularly used in the treatment of cancer, skin, neurodegenerative and autoimmune diseases. However, ATRA is very easy to be metabolized into 4-hydroxyl-RA in vivo by CYP26A1, an inducible cytochrome P450 enzyme, eventually into more polar metabolites. Therefore, it is vital to develop specific retinoic acid metabolism blocking agents (RAMBAs) to inhibit the metabolic enzyme CYP26A1 in the treatment of relevant diseases aforementioned. In this study, CYP26A1 and its interactions with retinoic acid-competitive metabolism blocking agents were investigated by a combined ligand- and structure-based approach. First, since the crystal structure of CYP26A1 protein has not been determined, we constructed the 3D structure of CYP26A1 using homology modeling. In order to achieve a deeper insight into the mode of action of RAMBAs in the active site, the molecular superimposition model and the common feature pharmacophore model were constructed, and molecular docking was performed. The molecular superimposition model is composed of three features: the main chain groups, side chain groups, and azole groups. The common feature pharmacophore model consists of five chemical features: four hydrophobic groups and one hydrogen acceptor (HHHHA). The results of molecular docking show that the characteristic groups of RAMBAs were mapped into three different active pockets, respectively. A structure-activity relationship (SAR) was obtained by a combination of the molecular superimposition and docking results with the pharmacophore model. This study gives more insight into the interaction model inside the CYP26A1 active site and provides guidance for the design of more potent and possibly more selective RAMBAs.

  4. Limiting dilution analysis (LDA) of cells responding to recombinant interleukin-2 without previous stimulation: evidence that all responding cells are lymphokine-activated potent effectors.

    PubMed Central

    Vie, H; Bonneville, M; Sondermeyer, P; Moreau, J F; Soulillou, J P

    1986-01-01

    The relationship between peripheral blood mononucleated cells spontaneously bearing the IL-2 receptor (IL-2R) and cell cytotoxicity for the natural killer (NK)-sensitive K562 target cell line was investigated. For this purpose, three types of experiments were performed. (i) Positive selection of cells spontaneously bearing the IL-2R was carried out by culturing peripheral blood lymphocytes (PBL) in the sole presence of recombinant IL-2 (rIL-2). Cytotoxicity was assessed at Day 6 of the culture in a 4 hr cytotoxic assay. (ii) Negative selection was performed by complement mediated lysis using the B1.49.9 monoclonal antibody which is specific for the IL-2R. (iii) Limiting dilution analysis of non-adherent PBL was carried out in the presence of rIL-2 alone. The colonies obtained were divided and daughter colonies assayed for anti-K562 cytotoxicity in a 6 hr cytotoxic assay and for proliferation. The results show that: (i) a 6-day culture of human non-adherent PBL in the presence of rIL-2 alone leads to a sharp increase in anti-K562 cytotoxicity; (ii) depletion of B1.49.9 positive PBL strongly decreases cytotoxicity against K562 targets; (iii) limiting dilution analysis indicates that all colonies grown without activation in the presence of autologous serum and rIL-2 can mediate cytotoxicity against K562 targets, which is not the case when the starting population is activated. Thus, our data taken together strongly suggest that lymphocytes spontaneously bearing the IL-2R are directly involved in K562 lysis by fresh PBL (classical NK activity). Moreover, we demonstrate that all colonies able to proliferate without any activation, in the sole presence of rIL-2, are potent K562 killers (in this case, these cells correspond to the so-called lymphokine activated killers, LAK). PMID:3082744

  5. Phenolic indeno[1,2-b]indoles as ABCG2-selective potent and non-toxic inhibitors stimulating basal ATPase activity.

    PubMed

    Gozzi, Gustavo Jabor; Bouaziz, Zouhair; Winter, Evelyn; Daflon-Yunes, Nathalia; Honorat, Mylène; Guragossian, Nathalie; Marminon, Christelle; Valdameri, Glaucio; Bollacke, Andre; Guillon, Jean; Pinaud, Noël; Marchivie, Mathieu; Cadena, Silvia M; Jose, Joachim; Le Borgne, Marc; Di Pietro, Attilio

    2015-01-01

    Ketonic indeno[1,2-b]indole-9,10-dione derivatives, initially designed as human casein kinase II (CK2) inhibitors, were recently shown to be converted into efficient inhibitors of drug efflux by the breast cancer resistance protein ABCG2 upon suited substitutions including a N (5)-phenethyl on C-ring and hydrophobic groups on D-ring. A series of ten phenolic and seven p-quinonic derivatives were synthesized and screened for inhibition of both CK2 and ABCG2 activities. The best phenolic inhibitors were about threefold more potent against ABCG2 than the corresponding ketonic derivatives, and showed low cytotoxicity. They were selective for ABCG2 over both P-glycoprotein and MRP1 (multidrug resistance protein 1), whereas the ketonic derivatives also interacted with MRP1, and they additionally displayed a lower interaction with CK2. Quite interestingly, they strongly stimulated ABCG2 ATPase activity, in contrast to ketonic derivatives, suggesting distinct binding sites. In contrast, the p-quinonic indenoindoles were cytotoxic and poor ABCG2 inhibitors, whereas a partial inhibition recovery could be reached upon hydrophobic substitutions on D-ring, similarly to the ketonic derivatives.

  6. A Schiff base-derived copper (II) complex is a potent inducer of apoptosis in colon cancer cells by activating the intrinsic pathway.

    PubMed

    Hajrezaie, Maryam; Paydar, Mohammadjavad; Moghadamtousi, Soheil Zorofchian; Hassandarvish, Pouya; Gwaram, Nura Suleiman; Zahedifard, Maryam; Rouhollahi, Elham; Karimian, Hamed; Looi, Chung Yeng; Ali, Hapipah Mohd; Abdul Majid, Nazia; Abdulla, Mahmood Ameen

    2014-01-01

    Metal-based drugs with extensive clinical applications hold great promise for the development of cancer chemotherapeutic agents. In the last few decades, Schiff bases and their complexes have become well known for their extensive biological potential. In the present study, we examined the antiproliferative effect of a copper (II) complex on HT-29 colon cancer cells. The Cu(BrHAP)2 Schiff base compound demonstrated a potent antiproliferative effect in HT-29 cells, with an IC50 value of 2.87  μg/ml after 72 h of treatment. HT-29 cells treated with Cu (II) complexes underwent apoptosis death, as exhibited by a progressive elevation in the proportion of the G1 cell population. At a concentration of 6.25  μg/ml, the Cu(BrHAP)2 compound caused significant elevation in ROS production following perturbation of mitochondrial membrane potential and cytochrome c release, as assessed by the measurement of fluorescence intensity in stained cells. Furthermore, the activation of caspases 3/7 and 9 was part of the Cu (II) complex-induced apoptosis, which confirmed the involvement of mitochondrial-mediated apoptosis. Meanwhile, there was no significant activation of caspase-8. Taken together, these results imply that the Cu(BrHAP)2 compound is a potential candidate for further in vivo and clinical colon cancer studies to develop novel chemotherapeutic agents derived from metal-based agents.

  7. Targeting Attenuated Interferon-α to Myeloma Cells with a CD38 Antibody Induces Potent Tumor Regression with Reduced Off-Target Activity.

    PubMed

    Pogue, Sarah L; Taura, Tetsuya; Bi, Mingying; Yun, Yong; Sho, Angela; Mikesell, Glen; Behrens, Collette; Sokolovsky, Maya; Hallak, Hussein; Rosenstock, Moti; Sanchez, Eric; Chen, Haiming; Berenson, James; Doyle, Anthony; Nock, Steffen; Wilson, David S

    2016-01-01

    Interferon-α (IFNα) has been prescribed to effectively treat multiple myeloma (MM) and other malignancies for decades. Its use has waned in recent years, however, due to significant toxicity and a narrow therapeutic index (TI). We sought to improve IFNα's TI by, first, attaching it to an anti-CD38 antibody, thereby directly targeting it to MM cells, and, second, by introducing an attenuating mutation into the IFNα portion of the fusion protein rendering it relatively inactive on normal, CD38 negative cells. This anti-CD38-IFNα(attenuated) immunocytokine, or CD38-Attenukine™, exhibits 10,000-fold increased specificity for CD38 positive cells in vitro compared to native IFNα and, significantly, is ~6,000-fold less toxic to normal bone marrow cells in vitro than native IFNα. Moreover, the attenuating mutation significantly decreases IFNα biomarker activity in cynomolgus macaques indicating that this approach may yield a better safety profile in humans than native IFNα or a non-attenuated IFNα immunocytokine. In human xenograft MM tumor models, anti-CD38-IFNα(attenuated) exerts potent anti-tumor activity in mice, inducing complete tumor regression in most cases. Furthermore, anti-CD38-IFNα(attenuated) is more efficacious than standard MM treatments (lenalidomide, bortezomib, dexamethasone) and exhibits strong synergy with lenalidomide and with bortezomib in xenograft models. Our findings suggest that tumor-targeted attenuated cytokines such as IFNα can promote robust tumor killing while minimizing systemic toxicity. PMID:27611189

  8. Isolation, Co-Crystallization and Structure-Based Characterization of Anabaenopeptins as Highly Potent Inhibitors of Activated Thrombin Activatable Fibrinolysis Inhibitor (TAFIa)

    PubMed Central

    Schreuder, Herman; Liesum, Alexander; Lönze, Petra; Stump, Heike; Hoffmann, Holger; Schiell, Matthias; Kurz, Michael; Toti, Luigi; Bauer, Armin; Kallus, Christopher; Klemke-Jahn, Christine; Czech, Jörg; Kramer, Dan; Enke, Heike; Niedermeyer, Timo H. J.; Morrison, Vincent; Kumar, Vasant; Brönstrup, Mark

    2016-01-01

    Mature thrombin activatable fibrinolysis inhibitor (TAFIa) is a carboxypeptidase that stabilizes fibrin clots by removing C-terminal arginines and lysines from partially degraded fibrin. Inhibition of TAFIa stimulates the degradation of fibrin clots and may help to prevent thrombosis. Applying a lead finding approach based on literature-mining, we discovered that anabaenopeptins, cyclic peptides produced by cyanobacteria, were potent inhibitors of TAFIa with IC50 values as low as 1.5 nM. We describe the isolation and structure elucidation of 20 anabaenopeptins, including 13 novel congeners, as well as their pronounced structure-activity relationships (SAR) with respect to inhibition of TAFIa. Crystal structures of the anabaenopeptins B, C and F bound to the surrogate protease carboxypeptidase B revealed the binding modes of these large (~850 Da) compounds in detail and explained the observed SAR, i.e. the strong dependence of the potency on a basic (Arg, Lys) exocyclic residue that addressed the S1’ binding pocket, and a broad tolerance towards substitutions in the pentacyclic ring that acted as a plug of the active site. PMID:27604544

  9. Design, Synthesis, and Evaluation of in Vitro and in Vivo Anticancer Activity of 4-Substituted Coumarins: A Novel Class of Potent Tubulin Polymerization Inhibitors.

    PubMed

    Cao, Dong; Liu, Yibin; Yan, Wei; Wang, Chunyu; Bai, Peng; Wang, Taijin; Tang, Minghai; Wang, Xiaoyan; Yang, Zhuang; Ma, Buyun; Ma, Liang; Lei, Lei; Wang, Fang; Xu, Bixue; Zhou, Yuanyuan; Yang, Tao; Chen, Lijuan

    2016-06-23

    In this paper, a series of novel 4-substituted coumarin derivatives were synthesized. Among these compounds 34, 39, 40, 43, 62, 65, and 67 exhibited significant antiproliferative activity toward a panel of tumor cell lines at subnanomolar IC50 values. Compound 65 showed potent antiproliferative ability (IC50 values of 7-47 nM) and retained full activity in multidrug resistant cancer cells. Compound 65 caused G2/M phase arrest and interacted with the colchicine-binding site in tubulin, as confirmed by immune-fluorescence staining, microtubule dynamics assays, and competition assays with N,N'-ethylene-bis(iodoacetamide). Compound 65 reduced the cell migration and disrupted capillary-like tube formation in HUVEC cells. Importantly, compound 65 significantly and dose-dependently reduced tumor growth in four xenografts models including paclitaxel sensitive and resistant ovarian tumors (A2780s and A2780/T), adrmicycin sensitive and resistant breast tumors (MCF-7 and MCF-7/ADR), suggesting that compound 65 is a promising novel antimitotic compound for the potential treatment of cancer. PMID:27213819

  10. A quantitative structure-activity relationship (QSAR) study on a few series of potent, highly selective inhibitors of nitric oxide synthase.

    PubMed

    Bharti, Vishwa Deepak; Gupta, Satya P; Kumar, Harish

    2014-02-01

    QSAR study was performed on a series of 1,2-dihydro-4-quinazolinamines, 4,5-dialkylsubstituted-2-imino-1,3-thiazolidine derivatives and 4,5-disubstituted-1,3-oxazolidin-2-imine derivatives studied by Tinker et al. [J Med Chem (2003), 46, 913-916], Ueda et al. [Bioorg Med Chem (2004) 12, 4101-4116] and Ueda et al. [Bioorg Med Chem Lett (2004) 14, 313-316], respectively, as potent, highly selective inhibitors of inducible nitric oxide synthase (iNOS). The iNOS inhibition activity of the whole series of compounds was analyzed in relation to the physicochemical and molecular properties of the compounds. The QSAR analysis revealed that the inhibition potency of the compounds was controlled by a topological parameter 1chi(v) (Kier's first order valence molecular connectivity index), density (D), surface tension (St) and length (steric parameter) of a substituent. This suggested that the drug-receptor interaction predominantly involved the dispersion interaction, but the bulky molecule would face steric problem because of which the molecule may not completely fit in active sites of the receptor and thus may not have the optimum interaction.

  11. Repeated dosing of ABT-102, a potent and selective TRPV1 antagonist, enhances TRPV1-mediated analgesic activity in rodents, but attenuates antagonist-induced hyperthermia.

    PubMed

    Honore, Prisca; Chandran, Prasant; Hernandez, Gricelda; Gauvin, Donna M; Mikusa, Joseph P; Zhong, Chengmin; Joshi, Shailen K; Ghilardi, Joseph R; Sevcik, Molly A; Fryer, Ryan M; Segreti, Jason A; Banfor, Patricia N; Marsh, Kennan; Neelands, Torben; Bayburt, Erol; Daanen, Jerome F; Gomtsyan, Arthur; Lee, Chih-Hung; Kort, Michael E; Reilly, Regina M; Surowy, Carol S; Kym, Philip R; Mantyh, Patrick W; Sullivan, James P; Jarvis, Michael F; Faltynek, Connie R

    2009-03-01

    Transient receptor potential vanilloid type 1 (TRPV1) is a ligand-gated ion channel that functions as an integrator of multiple pain stimuli including heat, acid, capsaicin and a variety of putative endogenous lipid ligands. TRPV1 antagonists have been shown to decrease inflammatory pain in animal models and to produce limited hyperthermia at analgesic doses. Here, we report that ABT-102, which is a potent and selective TRPV1 antagonist, is effective in blocking nociception in rodent models of inflammatory, post-operative, osteoarthritic, and bone cancer pain. ABT-102 decreased both spontaneous pain behaviors and those evoked by thermal and mechanical stimuli in these models. Moreover, we have found that repeated administration of ABT-102 for 5-12 days increased its analgesic activity in models of post-operative, osteoarthritic, and bone cancer pain without an associated accumulation of ABT-102 concentration in plasma or brain. Similar effects were also observed with a structurally distinct TRPV1 antagonist, A-993610. Although a single dose of ABT-102 produced a self-limiting increase in core body temperature that remained in the normal range, the hyperthermic effects of ABT-102 effectively tolerated following twice-daily dosing for 2 days. Therefore, the present data demonstrate that, following repeated administration, the analgesic activity of TRPV1 receptor antagonists is enhanced, while the associated hyperthermic effects are attenuated. The analgesic efficacy of ABT-102 supports its advancement into clinical studies.

  12. Isolation, Co-Crystallization and Structure-Based Characterization of Anabaenopeptins as Highly Potent Inhibitors of Activated Thrombin Activatable Fibrinolysis Inhibitor (TAFIa).

    PubMed

    Schreuder, Herman; Liesum, Alexander; Lönze, Petra; Stump, Heike; Hoffmann, Holger; Schiell, Matthias; Kurz, Michael; Toti, Luigi; Bauer, Armin; Kallus, Christopher; Klemke-Jahn, Christine; Czech, Jörg; Kramer, Dan; Enke, Heike; Niedermeyer, Timo H J; Morrison, Vincent; Kumar, Vasant; Brönstrup, Mark

    2016-01-01

    Mature thrombin activatable fibrinolysis inhibitor (TAFIa) is a carboxypeptidase that stabilizes fibrin clots by removing C-terminal arginines and lysines from partially degraded fibrin. Inhibition of TAFIa stimulates the degradation of fibrin clots and may help to prevent thrombosis. Applying a lead finding approach based on literature-mining, we discovered that anabaenopeptins, cyclic peptides produced by cyanobacteria, were potent inhibitors of TAFIa with IC50 values as low as 1.5 nM. We describe the isolation and structure elucidation of 20 anabaenopeptins, including 13 novel congeners, as well as their pronounced structure-activity relationships (SAR) with respect to inhibition of TAFIa. Crystal structures of the anabaenopeptins B, C and F bound to the surrogate protease carboxypeptidase B revealed the binding modes of these large (~850 Da) compounds in detail and explained the observed SAR, i.e. the strong dependence of the potency on a basic (Arg, Lys) exocyclic residue that addressed the S1' binding pocket, and a broad tolerance towards substitutions in the pentacyclic ring that acted as a plug of the active site. PMID:27604544

  13. A Schiff Base-Derived Copper (II) Complex Is a Potent Inducer of Apoptosis in Colon Cancer Cells by Activating the Intrinsic Pathway

    PubMed Central

    Hajrezaie, Maryam; Paydar, Mohammadjavad; Zorofchian Moghadamtousi, Soheil; Hassandarvish, Pouya; Gwaram, Nura Suleiman; Zahedifard, Maryam; Rouhollahi, Elham; Karimian, Hamed; Looi, Chung Yeng; Ali, Hapipah Mohd; Abdul Majid, Nazia; Abdulla, Mahmood Ameen

    2014-01-01

    Metal-based drugs with extensive clinical applications hold great promise for the development of cancer chemotherapeutic agents. In the last few decades, Schiff bases and their complexes have become well known for their extensive biological potential. In the present study, we examined the antiproliferative effect of a copper (II) complex on HT-29 colon cancer cells. The Cu(BrHAP)2 Schiff base compound demonstrated a potent antiproliferative effect in HT-29 cells, with an IC50 value of 2.87 μg/ml after 72 h of treatment. HT-29 cells treated with Cu (II) complexes underwent apoptosis death, as exhibited by a progressive elevation in the proportion of the G1 cell population. At a concentration of 6.25 μg/ml, the Cu(BrHAP)2 compound caused significant elevation in ROS production following perturbation of mitochondrial membrane potential and cytochrome c release, as assessed by the measurement of fluorescence intensity in stained cells. Furthermore, the activation of caspases 3/7 and 9 was part of the Cu (II) complex-induced apoptosis, which confirmed the involvement of mitochondrial-mediated apoptosis. Meanwhile, there was no significant activation of caspase-8. Taken together, these results imply that the Cu(BrHAP)2 compound is a potential candidate for further in vivo and clinical colon cancer studies to develop novel chemotherapeutic agents derived from metal-based agents. PMID:24737979

  14. Advanced Glycation End Products (AGE) Potently Induce Autophagy through Activation of RAF Protein Kinase and Nuclear Factor κB (NF-κB).

    PubMed

    Verma, Neeharika; Manna, Sunil K

    2016-01-15

    Advanced glycation end products (AGE) accumulate in diabetic patients and aging people because of high amounts of three- or four-carbon sugars derived from glucose, thereby causing multiple consequences, including inflammation, apoptosis, obesity, and age-related disorders. It is important to understand the mechanism of AGE-mediated signaling leading to the activation of autophagy (self-eating) that might result in obesity. We detected AGE as one of the potent inducers of autophagy compared with doxorubicin and TNF. AGE-mediated autophagy is inhibited by suppression of PI3K and potentiated by the autophagosome maturation blocker bafilomycin. It increases autophagy in different cell types, and that correlates with the expression of its receptor, receptor for AGE. LC3B, the marker for autophagosomes, is shown to increase upon AGE stimulation. AGE-mediated autophagy is partially suppressed by inhibitor of NF-κB, PKC, or ERK alone and significantly in combination. AGE increases sterol regulatory element binding protein activity, which leads to an increase in lipogenesis. Although AGE-mediated lipogenesis is affected by autophagy inhibitors, AGE-mediated autophagy is not influenced by lipogenesis inhibitors, suggesting that the turnover of lipid droplets overcomes the autophagic clearance. For the first time, we provide data showing that AGE induces several cell signaling cascades, like NF-κB, PKC, ERK, and MAPK, that are involved in autophagy and simultaneously help with the accumulation of lipid droplets that are not cleared effectively by autophagy, therefore causing obesity.

  15. Phenolic indeno[1,2-b]indoles as ABCG2-selective potent and non-toxic inhibitors stimulating basal ATPase activity

    PubMed Central

    Gozzi, Gustavo Jabor; Bouaziz, Zouhair; Winter, Evelyn; Daflon-Yunes, Nathalia; Honorat, Mylène; Guragossian, Nathalie; Marminon, Christelle; Valdameri, Glaucio; Bollacke, Andre; Guillon, Jean; Pinaud, Noël; Marchivie, Mathieu; Cadena, Silvia M; Jose, Joachim; Le Borgne, Marc; Di Pietro, Attilio

    2015-01-01

    Ketonic indeno[1,2-b]indole-9,10-dione derivatives, initially designed as human casein kinase II (CK2) inhibitors, were recently shown to be converted into efficient inhibitors of drug efflux by the breast cancer resistance protein ABCG2 upon suited substitutions including a N5-phenethyl on C-ring and hydrophobic groups on D-ring. A series of ten phenolic and seven p-quinonic derivatives were synthesized and screened for inhibition of both CK2 and ABCG2 activities. The best phenolic inhibitors were about threefold more potent against ABCG2 than the corresponding ketonic derivatives, and showed low cytotoxicity. They were selective for ABCG2 over both P-glycoprotein and MRP1 (multidrug resistance protein 1), whereas the ketonic derivatives also interacted with MRP1, and they additionally displayed a lower interaction with CK2. Quite interestingly, they strongly stimulated ABCG2 ATPase activity, in contrast to ketonic derivatives, suggesting distinct binding sites. In contrast, the p-quinonic indenoindoles were cytotoxic and poor ABCG2 inhibitors, whereas a partial inhibition recovery could be reached upon hydrophobic substitutions on D-ring, similarly to the ketonic derivatives. PMID:26170632

  16. Anticonvulsant activity, neural tube defect induction, mutagenicity and pharmacokinetics of a new potent antiepileptic drug, N-methoxy-2,2,3,3-tetramethylcyclopropane carboxamide.

    PubMed

    Sobol, Eyal; Yagen, Boris; Lamb, John G; White, H Steve; Wlodarczyk, Bogdan J; Finnell, Richard H; Bialer, Meir

    2007-01-01

    N-methoxy-2,2,3,3-tetramethylcyclopropane carboxamide (OM-TMCD) is a methoxyamide derivative of a cyclopropyl analogue of valproic acid (VPA). The structural considerations used in the design of OM-TMCD were aimed to enhance OM-TMCD anticonvulsant potency (compared to VPA) and to prevent VPA's two life-threatening side effects, i.e., induction of neural tube defects (NTDs) and hepatotoxicity. Following i.p. administration to rats OM-TMCD demonstrated a broad spectrum of anticonvulsant activity and showed better potency than VPA in the maximal electroshock seizure and subcutaneous pentylenetetrazole tests as well as in the hippocampal kindling model. OM-TMCD was inactive in the mouse 6-Hz test at 100 mg/kg dose. Teratogenicity studies performed in a SWV/Fnn-mouse model for VPA-induced-exencephaly showed that on the equimolar basis OM-TMCD possesses the same fetal toxicity and ability to induce NTDs as VPA, but since OM-TMCD is a much more potent anticonvulsant its activity/exencephaly formation ratio appears to be much more beneficial than that of VPA. OM-TMCD was found to be non-mutagenic and non-pro-mutagenic in the Ames test. It showed a beneficial pharmacokinetic profile in rats, having a high oral bioavailability of 75% and satisfactory values of clearance and volume of distribution. These results support further studies to fully characterize the therapeutic potential of OM-TMCD.

  17. Targeting Attenuated Interferon-α to Myeloma Cells with a CD38 Antibody Induces Potent Tumor Regression with Reduced Off-Target Activity

    PubMed Central

    Pogue, Sarah L.; Taura, Tetsuya; Bi, Mingying; Yun, Yong; Sho, Angela; Mikesell, Glen; Behrens, Collette; Sokolovsky, Maya; Hallak, Hussein; Rosenstock, Moti; Sanchez, Eric; Chen, Haiming; Berenson, James; Doyle, Anthony; Nock, Steffen; Wilson, David S.

    2016-01-01

    Interferon-α (IFNα) has been prescribed to effectively treat multiple myeloma (MM) and other malignancies for decades. Its use has waned in recent years, however, due to significant toxicity and a narrow therapeutic index (TI). We sought to improve IFNα’s TI by, first, attaching it to an anti-CD38 antibody, thereby directly targeting it to MM cells, and, second, by introducing an attenuating mutation into the IFNα portion of the fusion protein rendering it relatively inactive on normal, CD38 negative cells. This anti-CD38-IFNα(attenuated) immunocytokine, or CD38-Attenukine™, exhibits 10,000-fold increased specificity for CD38 positive cells in vitro compared to native IFNα and, significantly, is ~6,000-fold less toxic to normal bone marrow cells in vitro than native IFNα. Moreover, the attenuating mutation significantly decreases IFNα biomarker activity in cynomolgus macaques indicating that this approach may yield a better safety profile in humans than native IFNα or a non-attenuated IFNα immunocytokine. In human xenograft MM tumor models, anti-CD38-IFNα(attenuated) exerts potent anti-tumor activity in mice, inducing complete tumor regression in most cases. Furthermore, anti-CD38-IFNα(attenuated) is more efficacious than standard MM treatments (lenalidomide, bortezomib, dexamethasone) and exhibits strong synergy with lenalidomide and with bortezomib in xenograft models. Our findings suggest that tumor-targeted attenuated cytokines such as IFNα can promote robust tumor killing while minimizing systemic toxicity. PMID:27611189

  18. Thiolates Chemically Induce Redox Activation of BTZ043 and Related Potent Nitro Aromatic Anti-Tuberculosis Agents

    PubMed Central

    Tiwari, Rohit; Moraski, Garrett C.; Krchňák, Viktor; Miller, Patricia A.; Colon-Martinez, Mariangelli; Herrero, Eliza; Oliver, Allen G.; Miller, Marvin J.

    2013-01-01

    The development of multidrug resistant (MDR) and extensively drug resistant (XDR) forms of tuberculosis (TB) has stimulated research efforts globally to expand the new drug pipeline. Nitro aromatic compounds, including 1, 3-Benzothiazin-4-ones (BTZs) and related agents, are a promising new class for the treatment of TB. Research has shown that the nitroso intermediates of BTZs that are generated in vivo cause suicide inhibition of decaprenylphosphoryl-β-D-ribose 2′ oxidase (DprE1), which is responsible for cell wall arabinogalactan biosynthesis. We have designed and synthesized novel anti-TB agents inspired from BTZs and other nitroaromatic compounds. Computational studies indicated that the unsubstituted aromatic carbons of BTZ043 and related nitroaromatic compounds are the most electron deficient and might be prone to nucleophilic attack. Our chemical studies on BTZ043 and the additional nitro aromatic compounds synthesized by us and the others confirmed the postulated reactivity. The results indicate that nucleophiles such as thiolates, cyanide and hydride induce non-enzymatic reduction of the nitro groups present in these compounds to the corresponding nitroso intermediates by addition at the unsubstituted electron deficient aromatic carbon present in these compounds. Furthermore we demonstrate here that these compounds are good candidates for the classical von Richter reaction. These chemical studies offer an alternate hypotheses for the mechanism of action of nitro aromatic anti-TB agents in that the cysteine thiol(ate) or a hydride source at the active site of DprE1 may trigger the reduction of the nitro groups in a manner similar to the von Richter reaction to the nitroso intermediates, to initiate the inhibition of DprE1. PMID:23402278

  19. Apelin-36, a potent peptide, protects against ischemic brain injury by activating the PI3K/Akt pathway.

    PubMed

    Gu, Qin; Zhai, Lijing; Feng, Xing; Chen, Jing; Miao, Zhigang; Ren, Liyan; Qian, Xuanchen; Yu, Jian; Li, Yan; Xu, Xingshun; Liu, Chun-Feng

    2013-11-01

    Apelin is an endogenous ligand of G protein-coupled receptor-apelin and angiotensin-1-like receptor (APJ). The biological effects of apelin-APJ system are reported in multiple systems including cardiovascular, endocrinal, and gastrointestinal system. Previous studies had shown that apelin-13 is a potential protective agent on cardiac ischemia; however, the role of apelin in the central nervous system remained unknown. In this study, we investigated therapeutic effects of apelin-36, a long form of apelin, in ischemic brain injury models. We found that apelin-36 reduced cerebral infarct volume in the middle cerebral artery occlusion (MCAO) model and the neonatal hypoxic/ischemic (H/I) injury model. Apelin-36 improved neurological deficits in the MCAO model and promoted long-term functional recovery after H/I brain injury. We further explored the protective mechanisms of apelin-36 on H/I brain injury. We clearly demonstrated that apelin-36 significantly reduced the levels of cleaved caspase-3 and Bax, two well-established apoptotic markers after H/I injury, indicating the anti-apoptotic activity of apelin-36 in ischemic injury. Since apelin-36 increased the level of phosphorylated Akt after H/I injury, we treated neonates with a specific PI3K inhibitor LY294002. We found that LY294002 decreased the phosphorylated Akt level and attenuated protective effects of apelin-36 on apoptosis. These suggested that the PI3K/Akt pathway was at least in part involved in the anti-apoptotic mechanisms of apelin-36. Our findings demonstrated that apelin-36 was a promising therapeutic agent on the treatment of ischemic brain injury.

  20. Potent antitumor activity of oncolytic adenovirus expressing Beclin-1 via induction of autophagic cell death in leukemia

    PubMed Central

    Liu, Hui; Li, Lu; Meng, Haitao; Qian, Qijun

    2013-01-01

    An attractive strategy among adenovirus-based oncolytic systems is to design adenoviral vectors to express pro-apoptotic genes, in which this gene-virotherapy approach significantly enhances tumor cell death by activating apoptotic pathways. However, the existence of cancer cells with apoptotic defects is one of the major obstacles in gene-virotherapy. Here, we investigated whether a strategy that combines the oncolytic effects of an adenoviral vector with simultaneous expression of Beclin-1, an autophagy gene, offers a therapeutic advantage for leukemia. A Beclin-1 cDNA was cloned in an oncolytic adenovirus with chimeric Ad5/11 fiber (SG511-BECN). SG511-BECN treatment induced significant autophagic cell death, and resulted in enhanced cell killing in a variety of leukemic cell lines and primary leukemic blasts. SG511-BECN effects were seen in chronic myeloid leukemia and acute myeloid leukemia with resistance to imatinib or chemotherapy, but exhibited much less cytotoxicity on normal cells. The SG511-BECN-induced autophagic cell death could be partially reversed by RNA interference knockdown of UVRAG, ATG5, and ATG7. We also showed that SG511-BECN strongly inhibited the growth of leukemic progenitors in vitro. In murine leukemia models, SG511-BECN prolonged the survival and decreased the xenograft tumor size by inducing autophagic cell death. Our results suggest that infection of leukemia cells with an oncolytic adenovirus overexpressing Beclin-1 can induce significant autophagic cell death and provide a new strategy for the elimination of leukemic cells via a unique mechanism of action distinct from apoptosis. PMID:23765161

  1. Anxiolytic and antidepressant-like activities of the novel and potent non-imidazole histamine H₃ receptor antagonist ST-1283.

    PubMed

    Bahi, Amine; Schwed, Johannes Stephan; Walter, Miriam; Stark, Holger; Sadek, Bassem

    2014-01-01

    Previous studies have suggested a potential link between histamine H₃ receptors (H₃R) signaling and anxiolytic-like and antidepressant-like effects. The aim of this study was to investigate the acute effects of ST-1283, a novel H₃R antagonist, on anxiety-related and depression-related behaviors in comparison with those of diazepam and fluoxetine. The effects of ST-1283 were evaluated using the elevated plus maze test, open field test, marbles burying test, tail suspension test, novelty suppressed feeding test, and forced swim test in male C57BL/6 mice. The results showed that, like diazepam, ST-1283 (7.5 mg/kg) significantly modified all the parameters observed in the elevated plus maze test. In addition, ST-1283 significantly increased the amount of time spent in the center of the arena without altering general motor activity in the open field test. In the same vein, ST-1283 reduced the number of buried marbles as well as time spent digging in the marbles burying test. The tail suspension test and forced swim test showed that ST-1283 was able to reduce immobility time, like the recognized antidepressant drug fluoxetine. In the novelty suppressed feeding test, treatment with ST-1283 decreased latency to feed with no effect on food intake in the home cage. Importantly, pretreatment with the H₃R agonist R-α-methylhistamine abrogated the anxiolytic and antidepressant effects of ST-1283. Taken together, the present series of studies demonstrates the novel effects of this newly synthesized H₃R antagonist in a number of preclinical models of psychiatric disorders and highlights the histaminergic system as a potential therapeutic target for the treatment of anxiety-related and depression-related disorders.

  2. Targeting of the orphan receptor GPR35 by pamoic acid: a potent activator of extracellular signal-regulated kinase and β-arrestin2 with antinociceptive activity.

    PubMed

    Zhao, Pingwei; Sharir, Haleli; Kapur, Ankur; Cowan, Alan; Geller, Ellen B; Adler, Martin W; Seltzman, Herbert H; Reggio, Patricia H; Heynen-Genel, Susanne; Sauer, Michelle; Chung, Thomas D Y; Bai, Yushi; Chen, Wei; Caron, Marc G; Barak, Larry S; Abood, Mary E

    2010-10-01

    Known agonists of the orphan receptor GPR35 are kynurenic acid, zaprinast, 5-nitro-2-(3-phenylproplyamino) benzoic acid, and lysophosphatidic acids. Their relatively low affinities for GPR35 and prominent off-target effects at other pathways, however, diminish their utility for understanding GPR35 signaling and for identifying potential therapeutic uses of GPR35. In a screen of the Prestwick Library of drugs and drug-like compounds, we have found that pamoic acid is a potent GPR35 agonist. Pamoic acid is considered by the Food and Drug Administration as an inactive compound that enables long-acting formulations of numerous drugs, such as the antihelminthics oxantel pamoate and pyrantel pamoate; the psychoactive compounds hydroxyzine pamoate (Vistaril) and imipramine pamoate (Tofranil-PM); and the peptide hormones triptorelin pamoate (Trelstar) and octreotide pamoate (OncoLar). We have found that pamoic acid induces a G(i/o)-linked, GPR35-mediated increase in the phosphorylation of extracellular signal-regulated kinase 1/2, recruitment of β-arrestin2 to GPR35, and internalization of GPR35. In mice, it attenuates visceral pain perception, indicating an antinociceptive effect, possibly through GPR35 receptors. We have also identified in collaboration with the Sanford-Burnham Institute Molecular Libraries Probe Production Center new classes of GPR35 antagonist compounds, including the nanomolar potency antagonist methyl-5-[(tert-butylcarbamothioylhydrazinylidene)methyl]-1-(2,4-difluorophenyl)pyrazole-4-carboxylate (CID2745687). Pamoic acid and potent antagonists such as CID2745687 present novel opportunities for expanding the chemical space of GPR35, elucidating GPR35 pharmacology, and stimulating GPR35-associated drug development. Our results indicate that the unexpected biological functions of pamoic acid may yield potential new uses for a common drug constituent. PMID:20826425

  3. Substituted (pyridylmethoxy)naphthalenes as potent and orally active 5-lipoxygenase inhibitors; synthesis, biological profile, and pharmacokinetics of L-739,010.

    PubMed

    Hamel, P; Riendeau, D; Brideau, C; Chan, C C; Desmarais, S; Delorme, D; Dubé, D; Ducharme, Y; Ethier, D; Grimm, E; Falgueyret, J P; Guay, J; Jones, T R; Kwong, E; McAuliffe, M; McFarlane, C S; Piechuta, H; Roumi, M; Tagari, P; Young, R N; Girard, Y

    1997-08-29

    Dioxabicyclooctanyl naphthalenenitriles have been reported as a class of potent and nonredox 5-lipoxygenase (5-LO) inhibitors. These bicyclo derivatives were shown to be metabolically more stable than their tetrahydropyranyl counterparts but were not well orally absorbed. Replacement of the phenyl ring in the naphthalenenitrile 1 by a pyridine ring leads to the potent and orally absorbed inhibitor 3g (L-739,010, 2-cyano-4-(3-furyl)-7-[[6-[3-(3-hydroxy-6,8-dioxabicyclo[3.2.1] octanyl)]-2-pyridyl]methoxy]naphthalene). Compound 3g inhibits 5-HPETE production by human 5-LO and LTB4 biosynthesis by human PMN leukocytes and human whole blood (IC50S of 20, 1.6, and 42 nM, respectively). Derivative 3g is orally active in the rat pleurisy model (inhibition of LTB4, ED50 = 0.3 mg/kg) and in the anesthetized dog model (inhibition of ex vivo whole blood LTB4 and urinary LTE4, ED50 = 0.45 and 0.23 microgram/kg/min, respectively, i.v. infusion). In addition, 3g shows excellent functional activity against ovalbumin-induced dyspnea in rats (60% inhibition at 0.5 mg/kg, 4 h pretreatment) and Ascaris-induced bronchoconstriction in conscious sheep (50% and > 85% inhibition in early and late phases, respectively at 2.5 micrograms/kg/min, i.v. infusion) and, more particularly in the conscious antigen sensitive squirrel monkey model (53% inhibition of the increase in RL and 76% in the decrease of Cdyn, at 0.1 mg/kg, po). In rats and dogs, 3g presents excellent pharmacokinetics (estimated half-lives of 5 and 16 h, respectively) and bioavailabilities (26% and 73% when dosed as its hydrochloride salt at doses of 20 and 10 mg/kg, respectively, in methocel suspension). Based on its overall biological profile, compound 3g has been selected for preclinical animal toxicity studies.

  4. Identification, Characterization, and Recombinant Expression of Epidermicin NI01, a Novel Unmodified Bacteriocin Produced by Staphylococcus epidermidis That Displays Potent Activity against Staphylococci

    PubMed Central

    Sandiford, Stephanie

    2012-01-01

    We describe the discovery, purification, characterization, and expression of an antimicrobial peptide, epidermicin NI01, which is an unmodified bacteriocin produced by Staphylococcus epidermidis strain 224. It is a highly cationic, hydrophobic, plasmid-encoded peptide that exhibits potent antimicrobial activity toward a wide range of pathogenic Gram-positive bacteria including methicillin-resistant Staphylococcus aureus (MRSA), enterococci, and biofilm-forming S. epidermidis strains. Purification of the peptide was achieved using a combination of hydrophobic interaction, cation exchange, and high-performance liquid chromatography (HPLC). Matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) analysis yielded a molecular mass of 6,074 Da, and partial sequence data of the peptide were elucidated using a combination of tandem mass spectrometry (MS/MS) and de novo sequencing. The draft genome sequence of the producing strain was obtained using 454 pyrosequencing technology, thus enabling the identification of the structural gene using the de novo peptide sequence data previously obtained. Epidermicin NI01 contains 51 residues with four tryptophan and nine lysine residues, and the sequence showed approximately 50% identity to peptides lacticin Z, lacticin Q, and aureocin A53, all of which belong to a new family of unmodified type II-like bacteriocins. The peptide is active in the nanomolar range against S. epidermidis, MRSA isolates, and vancomycin-resistant enterococci. Other unique features displayed by epidermicin include a high degree of protease stability and the ability to retain antimicrobial activity over a pH range of 2 to 10, and exposure to the peptide does not result in development of resistance in susceptible isolates. In this study we also show the structural gene alone can be cloned into Escherichia coli strain BL21(DE3), and expression yields active peptide. PMID:22155816

  5. Flavonoids of Cynara scolymus possess potent xanthinoxidase inhibitory activity in vitro but are devoid of hypouricemic effects in rats after oral application.

    PubMed

    Sarawek, Sasiporn; Feistel, Bjoern; Pischel, Ivo; Butterweck, Veronika

    2008-02-01

    Artichoke (Cynara scolymus L.) leaves have been historically used for the treatment of hyperuricemia and gout, however whether artichoke is truly efficacious for this indication, is still a matter of debate. Thus, the goal of the present study was first to examine the xanthine oxidase (XO) inhibitory activity of an artichoke leaf extract (ALE) and some of its main compounds in vitro and then further test potentially active substances for possible hypouricemic effects using an in vivo rat model. The in vitro study showed that ALE inhibited XO with only minimal inhibitory action (< 5 %) at 100 microg/mL. However, when selected compounds were tested, the caffeic acid derivatives revealed a weak XO inhibitory effect with IC (50) > 100 microM. From the tested flavones the aglycone luteolin potently inhibited XO with an IC (50) value of 1.49 microM. Luteolin 7-O-glucoside and luteolin 7-O-glucuronide showed lower XO inhibition activities with IC (50) values of 19.90 microM and 20.24 microM, respectively. However, oral administration of an aqueous ALE, luteolin, and luteolin 7-O-glucoside did not produce any observable hypouricemic effects after acute oral treatment in potassium oxonate-treated rats. After intraperitoneal injection of luteolin a decrease in uric acid levels was detected suggesting that the hypouricemic effects of luteolin are due to its original form rather than its metabolites produced by the gut flora. In conclusion, an aqueous ALE, caffeic acid derivatives and flavones exerted XO inhibitory effects in vitro but a hypouricemic activity could not be confirmed after oral administration.

  6. Anti-myeloma activity of a multi targeted kinase inhibitor, AT9283, via potent Aurora Kinase and STAT3 inhibition either alone or in combination with lenalidomide

    PubMed Central

    Santo, Loredana; Hideshima, Teru; Cirstea, Diana; Bandi, Madhavi; Nelson, Erik A.; Gorgun, Gullu; Rodig, Scott; Vallet, Sonia; Pozzi, Samantha; Patel, Kishan; Unitt, Christine; Squires, Matt; Hu, Yiguo; Chauhan, Dharminder; Mahindra, Anuj; Munshi, Nikhil C.; Anderson, Kenneth C.; Raje, Noopur

    2014-01-01

    Purpose Aurora Kinases, whose expression is linked to genetic instability and cellular proliferation, are under investigation as novel therapeutic targets in multiple myeloma (MM). Here, we investigated the preclinical activity of a small molecule–multi-targeted kinase inhibitor, AT9283, with potent activity against Aurora kinase A (AURKA), Aurora kinase B (AURKB) and Janus Kinase 2/3. Experimental design We evaluated the in vitro anti myeloma activity of AT9283 alone and in combination with lenalidomide and the in vivo efficacy by using a Xenograft mouse model of human MM. Results Our data demonstrated AT9283 induced cell growth inhibition and apoptosis in MM. Studying the apoptosis mechanism of AT9283 in MM, we observed features consistent with both AURKA and AURKB inhibition, e.g increase of cells with polyploid DNA content, decrease in phospho-Histone H3, and decrease of phospho-Aurora A. Importantly, AT9283 also inhibited STAT3 tyrosine phosphorylation in MM cells. Genetic depletion of STAT3, AURKA or AURKB showed growth inhibition of MM cells, suggesting a role of AT9283-induced inhibition of these molecules in the underlying mechanism of MM cell death. In vivo studies demonstrated decreased MM cell growth and prolonged survival in AT9283-treated mice compared to controls. Importantly, combination studies of AT9283 with lenalidomide showed significant synergistic cytotoxicity in MM cells, even in the presence of bone marrow stromal cells (BMSCs). Enhanced cytotoxicity was associated with increased inhibition of pSTAT3 and pERK. Conclusions Demonstration of in vitro and in vivo anti-MM activity of AT9283 provides the rationale for the clinical evaluation of AT9283 as monotherapy and in combination in patients with MM. PMID:21430070

  7. Identification, characterization, and recombinant expression of epidermicin NI01, a novel unmodified bacteriocin produced by Staphylococcus epidermidis that displays potent activity against Staphylococci.

    PubMed

    Sandiford, Stephanie; Upton, Mathew

    2012-03-01

    We describe the discovery, purification, characterization, and expression of an antimicrobial peptide, epidermicin NI01, which is an unmodified bacteriocin produced by Staphylococcus epidermidis strain 224. It is a highly cationic, hydrophobic, plasmid-encoded peptide that exhibits potent antimicrobial activity toward a wide range of pathogenic Gram-positive bacteria including methicillin-resistant Staphylococcus aureus (MRSA), enterococci, and biofilm-forming S. epidermidis strains. Purification of the peptide was achieved using a combination of hydrophobic interaction, cation exchange, and high-performance liquid chromatography (HPLC). Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) analysis yielded a molecular mass of 6,074 Da, and partial sequence data of the peptide were elucidated using a combination of tandem mass spectrometry (MS/MS) and de novo sequencing. The draft genome sequence of the producing strain was obtained using 454 pyrosequencing technology, thus enabling the identification of the structural gene using the de novo peptide sequence data previously obtained. Epidermicin NI01 contains 51 residues with four tryptophan and nine lysine residues, and the sequence showed approximately 50% identity to peptides lacticin Z, lacticin Q, and aureocin A53, all of which belong to a new family of unmodified type II-like bacteriocins. The peptide is active in the nanomolar range against S. epidermidis, MRSA isolates, and vancomycin-resistant enterococci. Other unique features displayed by epidermicin include a high degree of protease stability and the ability to retain antimicrobial activity over a pH range of 2 to 10, and exposure to the peptide does not result in development of resistance in susceptible isolates. In this study we also show the structural gene alone can be cloned into Escherichia coli strain BL21(DE3), and expression yields active peptide.

  8. Attenuation of rodent neuropathic pain by an orally active peptide, RAP-103, which potently blocks CCR2- and CCR5-mediated monocyte chemotaxis and inflammation.

    PubMed

    Padi, Satyanarayana S V; Shi, Xiang Q; Zhao, Yuan Q; Ruff, Michael R; Baichoo, Noel; Pert, Candace B; Zhang, Ji

    2012-01-01

    Chemokine signaling is important in neuropathic pain, with microglial cells expressing CCR2 playing a well-established key role. DAPTA, a HIV gp120-derived CCR5 entry inhibitor, has been shown to inhibit CCR5-mediated monocyte migration and to attenuate neuroinflammation. We report here that as a stabilized analog of DAPTA, the short peptide RAP-103 exhibits potent antagonism for both CCR2 (half maximal inhibitory concentration [IC50] 4.2 pM) and CCR5 (IC50 0.18 pM) in monocyte chemotaxis. Oral administration of RAP-103 (0.05-1 mg/kg) for 7 days fully prevents mechanical allodynia and inhibits the development of thermal hyperalgesia after partial ligation of the sciatic nerve in rats. Administered from days 8 to 12, RAP-103 (0.2-1 mg/kg) reverses already established hypersensitivity. RAP-103 relieves behavioral hypersensitivity, probably through either or both CCR2 and CCR5 blockade, because by using genetically deficient animals, we demonstrated that in addition to CCR2, CCR5 is also required for the development of neuropathic pain. Moreover, RAP-103 is able to reduce spinal microglial activation and monocyte infiltration, and to inhibit inflammatory responses evoked by peripheral nerve injury that cause chronic pain. Our findings suggest that targeting CCR2/CCR5 should provide greater efficacy than targeting CCR2 or CCR5 alone, and that dual CCR2/CCR5 antagonist RAP-103 has the potential for broad clinical use in neuropathic pain treatment.

  9. Design, Synthesis and Antitumor Activity of Novel link-bridge and B-Ring Modified Combretastatin A-4 (CA-4) Analogues as Potent Antitubulin Agents.

    PubMed

    Duan, Yong-Tao; Man, Ruo-Jun; Tang, Dan-Jie; Yao, Yong-Fang; Tao, Xiang-Xiang; Yu, Chen; Liang, Xin-Yi; Makawana, Jigar A; Zou, Mei-Juan; Wang, Zhong-Chang; Zhu, Hai-Liang

    2016-01-01

    A series of 12 novel acylhydrazone, chalcone and amide-bridged analogues of combretastatin A-4 were designed and synthesized toward tubulin. All these compounds were determined by elemental analysis, (1)H NMR, and MS. Among them, compound 7 with acylhydrazone-bridge, bearing a benzyl at the indole-N position, was identified as a potent antiproliferative agent against a panel of cancer cell lines with IC50 values ranging from 0.08 to 35.6 μM. In contrast, its cytotoxic effects on three normal human cells were minimal. Cellular studies have revealed that the induction of apoptosis by compound 7 was associated with a collapse of mitochondrial membrane potential, accumulation of reactive oxygen species, alterations in the expression of some cell cycle-related proteins (Cyclin B1, Cdc25c, Cdc2, P21) and some apoptosis-related proteins (Bax, PARP, Bcl-2, Caspase3). The docking mode showed the binding posture of CA-4 and compound 7 are similar in the colchicine-binding pocket of tubulin, as confirmed by colchicine-tubulin competitive binding assay, tubulin polymerization inhibitory activity, extracellular protein expression determination assay and confocal immunofluorescence microscopy. In vivo study, compound 7 effectively inhibited A549 xenograft tumor growth without causing significant loss of body weight suggesting that compound 7 is a promising new antimitotic agent with clinical potential.

  10. Enabling virtual screening of potent and safer antimicrobial agents against noma: mtk-QSBER model for simultaneous prediction of antibacterial activities and ADMET properties.

    PubMed

    Speck-Planche, Alejandro; Cordeiro, M N D S

    2015-01-01

    Neglected diseases are infections that thrive mainly among underdeveloped countries, particularly those belonging to regions found in Asia, Africa, and America. One of the most complex diseases is noma, a dangerous health condition characterized by a polymicrobial and opportunistic nature. The search for potent and safer antibacterial agents against this disease is therefore a goal of particular interest. Chemoinformatics can be used to rationalize the discovery of drug candidates, diminishing time and financial resources. However, in the case of noma, there is no in silico model available for its use in the discovery of efficacious antibacterial agents. This work is devoted to report the first mtk-QSBER model, which integrates dissimilar kinds of chemical and biological data. The model was generated with the aim of simultaneously predicting activity against bacteria present in noma, and ADMET (absorption, distribution, metabolism, elimination, toxicity) parameters. The mtk-QSBER model was constructed by employing a large and heterogeneous dataset of chemicals and displayed accuracies higher than 90% in both training and prediction sets. We confirmed the practical applicability of the model by predicting multiple profiles of the investigational antibacterial drug delafloxacin, and the predictions converged with the experimental reports. To date, this is the first model focused on the virtual search for desirable anti-noma agents. PMID:25769968

  11. Design, Synthesis and Antitumor Activity of Novel link-bridge and B-Ring Modified Combretastatin A-4 (CA-4) Analogues as Potent Antitubulin Agents

    PubMed Central

    Duan, Yong-Tao; Man, Ruo-Jun; Tang, Dan-Jie; Yao, Yong-Fang; Tao, Xiang-Xiang; Yu, Chen; Liang, Xin-Yi; Makawana, Jigar A.; Zou, Mei-Juan; Wang, Zhong-Chang; Zhu, Hai-Liang

    2016-01-01

    A series of 12 novel acylhydrazone, chalcone and amide–bridged analogues of combretastatin A-4 were designed and synthesized toward tubulin. All these compounds were determined by elemental analysis, 1H NMR, and MS. Among them, compound 7 with acylhydrazone-bridge, bearing a benzyl at the indole-N position, was identified as a potent antiproliferative agent against a panel of cancer cell lines with IC50 values ranging from 0.08 to 35.6 μM. In contrast, its cytotoxic effects on three normal human cells were minimal. Cellular studies have revealed that the induction of apoptosis by compound 7 was associated with a collapse of mitochondrial membrane potential, accumulation of reactive oxygen species, alterations in the expression of some cell cycle-related proteins (Cyclin B1, Cdc25c, Cdc2, P21) and some apoptosis-related proteins (Bax, PARP, Bcl-2, Caspase3). The docking mode showed the binding posture of CA-4 and compound 7 are similar in the colchicine-binding pocket of tubulin, as confirmed by colchicine-tubulin competitive binding assay, tubulin polymerization inhibitory activity, extracellular protein expression determination assay and confocal immunofluorescence microscopy. In vivo study, compound 7 effectively inhibited A549 xenograft tumor growth without causing significant loss of body weight suggesting that compound 7 is a promising new antimitotic agent with clinical potential. PMID:27138035

  12. Enabling virtual screening of potent and safer antimicrobial agents against noma: mtk-QSBER model for simultaneous prediction of antibacterial activities and ADMET properties.

    PubMed

    Speck-Planche, Alejandro; Cordeiro, M N D S

    2015-01-01

    Neglected diseases are infections that thrive mainly among underdeveloped countries, particularly those belonging to regions found in Asia, Africa, and America. One of the most complex diseases is noma, a dangerous health condition characterized by a polymicrobial and opportunistic nature. The search for potent and safer antibacterial agents against this disease is therefore a goal of particular interest. Chemoinformatics can be used to rationalize the discovery of drug candidates, diminishing time and financial resources. However, in the case of noma, there is no in silico model available for its use in the discovery of efficacious antibacterial agents. This work is devoted to report the first mtk-QSBER model, which integrates dissimilar kinds of chemical and biological data. The model was generated with the aim of simultaneously predicting activity against bacteria present in noma, and ADMET (absorption, distribution, metabolism, elimination, toxicity) parameters. The mtk-QSBER model was constructed by employing a large and heterogeneous dataset of chemicals and displayed accuracies higher than 90% in both training and prediction sets. We confirmed the practical applicability of the model by predicting multiple profiles of the investigational antibacterial drug delafloxacin, and the predictions converged with the experimental reports. To date, this is the first model focused on the virtual search for desirable anti-noma agents.

  13. Design, Synthesis and Antitumor Activity of Novel link-bridge and B-Ring Modified Combretastatin A-4 (CA-4) Analogues as Potent Antitubulin Agents.

    PubMed

    Duan, Yong-Tao; Man, Ruo-Jun; Tang, Dan-Jie; Yao, Yong-Fang; Tao, Xiang-Xiang; Yu, Chen; Liang, Xin-Yi; Makawana, Jigar A; Zou, Mei-Juan; Wang, Zhong-Chang; Zhu, Hai-Liang

    2016-01-01

    A series of 12 novel acylhydrazone, chalcone and amide-bridged analogues of combretastatin A-4 were designed and synthesized toward tubulin. All these compounds were determined by elemental analysis, (1)H NMR, and MS. Among them, compound 7 with acylhydrazone-bridge, bearing a benzyl at the indole-N position, was identified as a potent antiproliferative agent against a panel of cancer cell lines with IC50 values ranging from 0.08 to 35.6 μM. In contrast, its cytotoxic effects on three normal human cells were minimal. Cellular studies have revealed that the induction of apoptosis by compound 7 was associated with a collapse of mitochondrial membrane potential, accumulation of reactive oxygen species, alterations in the expression of some cell cycle-related proteins (Cyclin B1, Cdc25c, Cdc2, P21) and some apoptosis-related proteins (Bax, PARP, Bcl-2, Caspase3). The docking mode showed the binding posture of CA-4 and compound 7 are similar in the colchicine-binding pocket of tubulin, as confirmed by colchicine-tubulin competitive binding assay, tubulin polymerization inhibitory activity, extracellular protein expression determination assay and confocal immunofluorescence microscopy. In vivo study, compound 7 effectively inhibited A549 xenograft tumor growth without causing significant loss of body weight suggesting that compound 7 is a promising new antimitotic agent with clinical potential. PMID:27138035

  14. Rapid Discovery and Structure–Activity Relationships of Pyrazolopyrimidines That Potently Suppress Breast Cancer Cell Growth via SRC Kinase Inhibition with Exceptional Selectivity over ABL Kinase

    PubMed Central

    2016-01-01

    Novel pyrazolopyrimidines displaying high potency and selectivity toward SRC family kinases have been developed by combining ligand-based design and phenotypic screening in an iterative manner. Compounds were derived from the promiscuous kinase inhibitor PP1 to search for analogs that could potentially target a broad spectrum of kinases involved in cancer. Phenotypic screening against MCF7 mammary adenocarcinoma cells generated target-agnostic structure–activity relationships that biased subsequent designs toward breast cancer treatment rather than to a particular target. This strategy led to the discovery of two potent antiproliferative leads with phenotypically distinct anticancer mode of actions. Kinase profiling and further optimization resulted in eCF506, the first small molecule with subnanomolar IC50 for SRC that requires 3 orders of magnitude greater concentration to inhibit ABL. eCF506 exhibits excellent water solubility, an optimal DMPK profile and oral bioavailability, halts SRC-associated neuromast migration in zebrafish embryos without inducing life-threatening heart defects, and inhibits SRC phosphorylation in tumor xenografts in mice. PMID:27115835

  15. Discovery of Potent Anticancer Agent HJC0416, an Orally Bioavailable Small Molecule Inhibitor of Signal Transducer and Activator of Transcription 3 (STAT3)

    PubMed Central

    Chen, Haijun; Yang, Zhengduo; Ding, Chunyong; Xiong, Ailian; Wild, Christopher; Wang, Lili; Ye, Na; Cai, Guoshuai; Flores, Rudolfo M.; Ding, Ye; Shen, Qiang; Zhou, Jia

    2014-01-01

    In a continuing effort to develop orally bioavailable small-molecule STAT3 inhibitors as potential therapeutic agents for human cancer, a series of novel diversified analogues based on our identified lead compound HJC0149 (1) (5-chloro-N-(1,1-dioxo-1H-1λ6-benzo[b]thiophen-6-yl)-2-hydroxybenzamide, Eur. J. Med. Chem. 2013, 62, 498–507) have been rationally designed, synthesized, and pharmacologically evaluated. Molecular docking studies and biological characterization supported our earlier findings that the O-alkylamino-tethered side chain on the hydroxyl group is an effective and essential structural determinant for improving biological activities and druglike properties of these molecules. Compounds with such modifications exhibited potent antiproliferative effects against breast and pancreatic cancer cell lines with IC50 values from low micromolar to nanomolar range. Among them, the newly discovered STAT3 inhibitor 12 (HJC0416) displayed an intriguing anticancer profile both in vitro and in vivo (i.p. & p.o.). More importantly, HJC0416 is an orally bioavailable anticancer agent as a promising candidate for further development. PMID:24904966

  16. Potent and rapid antigonococcal activity of the venom peptide BmKn2 and its derivatives against different Maldi biotype of multidrug-resistant Neisseria gonorrhoeae.

    PubMed

    Arpornsuwan, Teerakul; Buasakul, Brisana; Jaresitthikunchai, Janthima; Roytrakul, Sittiruk

    2014-03-01

    The emergence of multidrug-resistant strains of Neisseria gonorrhoeae constitutes a serious threat to public health and necessitates the discovery of new types of antimicrobial agents. Among the 18 clinical isolates of N. gonorrhoeae with susceptible to spectinomycin, ceftriaxone and cefixime, 14 isolates were resistance to penicillin, tetracycline and ciprofloxacin, while 2 isolates were susceptible to tetracycline and another was penicillin intermediate isolate. Significant differences between laboratory strain and multidrug resistant strains were revealed by means of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry profiling and bioinformatics examination using the MALDI BioTyper software. However, Maldi Biotyper was not successfully separated ciprofloxacin-penicillin resistance and ciprofloxacin-tetracycline resistance from ciprofloxacin-penicillin-tetracycline resistant N. gonorrhoeae isolates. BmKn2 is a basic, alpha-helical peptide with no disulfide-bridge venom peptides that was first isolated from Buthus martensii Kasch. A panel of BmKn2 scorpion venom peptide and its derivatives of varying length and characteristics were synthesized chemically and evaluated for their ability to inhibit the growth of clinical N. gonorrhoeae isolates. Synthetic BmKn2 displayed potent activity against 18 clinical isolates of N. gonorrhoeae with MIC50 values of 6.9-27.6 μM. BmKn2 exerted its antibacterial activity via a bactericidal mechanism. Cyclic BmKn1 did not show antigonococcal activity. Decreasing the cationicity and helix percentage at the C-terminus of BmKn2 reduced the potency against N. gonorrhoeae. Taken together, the BmKn1 peptide can be developed as a topical therapeutic agent for treating multidrug-resistant strains of N. gonorrhoeae infections. PMID:24184420

  17. Pharmacokinetics and pharmacodynamics of orally administered acetylenic tricyclic bis(cyanoenone), a highly potent Nrf2 activator with a reversible covalent mode of action

    PubMed Central

    Kostov, Rumen V.; Knatko, Elena V.; McLaughlin, Lesley A.; Henderson, Colin J.; Zheng, Suqing; Huang, Jeffrey T.-J.; Honda, Tadashi; Dinkova-Kostova, Albena T.

    2015-01-01

    The acetylenic tricyclic bis(cyanoenone) TBE-31 is a highly potent cysteine targeting compound with a reversible covalent mode of action; its best-characterized target being Kelch-like ECH-associated protein-1 (Keap1), the cellular sensor for oxidants and electrophiles. TBE-31 reacts with cysteines of Keap1, impairing its ability to target nuclear factor-erythroid 2 p45-related factor 2 (Nrf2) for degradation. Consequently, Nrf2 accumulates and orchestrates cytoprotective gene expression. In this study we investigated the pharmacokinetic and pharmacodynamic properties of TBE-31 in C57BL/6 mice. After a single oral dose of 10 μmol/kg (∼200 nmol/animal), the concentration of TBE-31 in blood exhibited two peaks, at 22.3 nM and at 15.5 nM, 40 min and 4 h after dosing, respectively, as determined by a quantitative stable isotope dilution LC-MS/MS method. The AUC0–24h was 195.5 h/nmol/l, the terminal elimination half-life was 10.2 h, and the kel was 0.068 h−1. To assess the pharmacodynamics of Nrf2 activation by TBE-31, we determined the enzyme activity of its prototypic target, NAD(P)H:quinone oxidoreductase 1 (NQO1) and found it elevated by 2.4- and 1.5-fold in liver and heart, respectively. Continuous feeding for 18 days with diet delivering the same daily doses of TBE-31 under conditions of concurrent treatment with the immunosuppressive agent azathioprine had a similar effect on Nrf2 activation without any indications of toxicity. Together with previous reports showing the cytoprotective effects of TBE-31 in animal models of carcinogenesis, our results demonstrate the high potency, efficacy and suitability for chronic administration of cysteine targeting reversible covalent drugs. PMID:26265043

  18. LSN2424100: a novel, potent orexin-2 receptor antagonist with selectivity over orexin-1 receptors and activity in an animal model predictive of antidepressant-like efficacy.

    PubMed

    Fitch, Thomas E; Benvenga, Mark J; Jesudason, Cynthia D; Zink, Charity; Vandergriff, Amy B; Menezes, Michelle M; Schober, Douglas A; Rorick-Kehn, Linda M

    2014-01-01

    We describe a novel, potent and selective orexin-2 (OX2)/hypocretin-2 receptor antagonist with in vivo activity in an animal model predictive of antidepressant-like efficacy. N-biphenyl-2-yl-4-fluoro-N-(1H-imidazol-2-ylmethyl) benzenesulfonamide HCl (LSN2424100) binds with high affinity to recombinant human OX2 receptors (Ki = 4.5 nM), and selectivity over OX1 receptors (Ki = 393 nM). LSN2424100 inhibited OXA-stimulated intracellular calcium release in HEK293 cells expressing human and rat OX2 receptors (Kb = 0.44 and 0.83 nM, respectively) preferentially over cells expressing human and rat OX1 (Kb = 90 and 175 nM, respectively). LSN2424100 exhibits good exposure in Sprague-Dawley rats after IP, but not PO, administration of a 30 mg/kg dose (AUC0-6 h = 1300 and 269 ng(*)h/mL, respectively). After IP administration in rats and mice, LSN2424100 produces dose-dependent antidepressant-like activity in the delayed-reinforcement of low-rate (DRL) assay, a model predictive of antidepressant-like efficacy. Efficacy in the DRL model was lost in mice lacking OX2, but not OX1 receptors, confirming OX2-specific activity. Importantly, antidepressant-like efficacy of the tricyclic antidepressant, imipramine, was maintained in both OX1 and OX2 receptor knock-out mice. In conclusion, the novel OX2 receptor antagonist, LSN2424100, is a valuable tool compound that can be used to explore the role of OX2 receptor-mediated signaling in mood disorders. PMID:24478625

  19. Potent Ex Vivo Activity of Naphthoquine and Methylene Blue against Drug-Resistant Clinical Isolates of Plasmodium falciparum and Plasmodium vivax.

    PubMed

    Wirjanata, Grennady; Sebayang, Boni F; Chalfein, Ferryanto; Prayoga; Handayuni, Irene; Trianty, Leily; Kenangalem, Enny; Noviyanti, Rintis; Campo, Brice; Poespoprodjo, Jeanne Rini; Möhrle, Jörg J; Price, Ric N; Marfurt, Jutta

    2015-10-01

    The 4-aminoquinoline naphthoquine (NQ) and the thiazine dye methylene blue (MB) have potent in vitro efficacies against Plasmodium falciparum, but susceptibility data for P. vivax are limited. The species- and stage-specific ex vivo activities of NQ and MB were assessed using a modified schizont maturation assay on clinical field isolates from Papua, Indonesia, where multidrug-resistant P. falciparum and P. vivax are prevalent. Both compounds were highly active against P. falciparum (median [range] 50% inhibitory concentration [IC50]: NQ, 8.0 nM [2.6 to 71.8 nM]; and MB, 1.6 nM [0.2 to 7.0 nM]) and P. vivax (NQ, 7.8 nM [1.5 to 34.2 nM]; and MB, 1.2 nM [0.4 to 4.3 nM]). Stage-specific drug susceptibility assays revealed significantly greater IC50s in parasites exposed at the trophozoite stage than at the ring stage for NQ in P. falciparum (26.5 versus 5.1 nM, P = 0.021) and P. vivax (341.6 versus 6.5 nM, P = 0.021) and for MB in P. vivax (10.1 versus 1.6 nM, P = 0.010). The excellent ex vivo activities of NQ and MB against both P. falciparum and P. vivax highlight their potential utility for the treatment of multidrug-resistant malaria in areas where both species are endemic.

  20. Alkylphenol Xenoestrogens with Varying Carbon Chain Lengths Differentially and Potently Activate Signaling and Functional Responses in GH3/B6/F10 Somatomammotropes

    PubMed Central

    Kochukov, Mikhail Y.; Jeng, Yow-Jiun; Watson, Cheryl S.

    2009-01-01

    Background Alkylphenols varying in their side-chain lengths [ethyl-, propyl-, octyl-, and nonylphenol (EP, PP, OP, and NP, respectively)] and bisphenol A (BPA) represent a large group of structurally related xenoestrogens that have endocrine-disruptive effects. Their rapid nongenomic effects that depend on structure for cell signaling and resulting functions are unknown. Objectives We compared nongenomic estrogenic activities of alkylphenols with BPA and 17β-estradiol (E2) in membrane estrogen receptor-α–enriched GH3/B6/F10 pituitary tumor cells. These actions included calcium (Ca) signaling, prolactin (PRL) release, extracellular-regulated kinase (ERK) phosphorylation, and cell proliferation. Methods We imaged Ca using fura-2, measured PRL release via radioimmunoassay, detected ERK phosphorylation by fixed cell immunoassay, and estimated cell number using the crystal violet assay. Results All compounds caused increases in Ca oscillation frequency and intracellular Ca volume at 100 fM to 1 nM concentrations, although long-chain alkylphenols were most effective. All estrogens caused rapid PRL release at concentrations as low as 1 fM to 10 pM; the potency of EP, PP, and NP exceeded that of E2. All compounds at 1 nM produced similar increases in ERK phosphorylation, causing rapid peaks at 2.5–5 min, followed by inactivation and additional 60-min peaks (except for BPA). Dose–response patterns of ERK activation at 5 min were similar for E2, BPA, and PP, whereas EP caused larger effects. Only E2 and NP increased cell number. Some rapid estrogenic responses showed correlations with the hydrophobicity of estrogenic molecules; the more hydrophobic OP and NP were superior at Ca and cell proliferation responses, whereas the less hydrophobic EP and PP were better at ERK activations. Conclusions Alkylphenols are potent estrogens in evoking these nongenomic responses contributing to complex functions; their hydrophobicity can largely predict these behaviors. PMID