Frequency of fruit and vegetable consumption and blood antioxidants in the Caerphilly cohort of older men

Objective: To assess the number of portions of fruit and vegetables consumed daily by a large representative sample of older men, and to determine how blood antioxidant (vitamins E, A and carotenoids) concentrations vary with fruit and vegetable consumption. Design: Cross-sectional study of free-living men. Subjects: Men aged 55-69 y (dietary data, n=1957; blood data, n=1874) participating in Phase III (1989-1993) of the Caerphilly and Speedwell Collaborative Heart Disease Studies. Methods: Dietary data were obtained by semi-quantitative food-frequency questionnaire and blood samples were analysed for antioxidant vitamins. Men were subdivided into groups on the basis of portions per day of fruit and vegetables. Within these sub-groups, mean and 95% ranges of intakes and of blood antioxidant levels were obtained. Log transformations were performed where appropriate. Results: Only 4.3% of the men met the recommended target of five portions, while 33.3% of the men consumed one or fewer portions of fruit and vegetables per day. Those men who consumed the poorest diets with respect to fruit and vegetable intakes were more likely to be from lower socio-economic classes, drink more alcohol and be current smokers. Fruit and vegetable intake reflected plasma concentrations of antioxidants, which showed a dose-response relationship to frequency of consumption. Conclusions: Older men in the UK consume much less fruit and vegetables than current recommendations. Major difficulties are likely to be encountered in trying to meet a dietary target that is clearly much higher than the fruit and vegetable consumption of large sections of the older population in the UK.

Significance of dietary antioxidants for health

Since evidence became available that free radicals were involved in mechanisms for the development of major diseases, including cardiovascular disease and cancer, there has been considerable research into the properties of natural dietary antioxidants. However, it has become clear that dietary antioxidants can only have beneficial effects in vivo by radical scavenging or effects on redox potential if they are present in tissues or bodily fluids at sufficient concentrations. For many dietary components, absorption is limited or metabolism into derivatives reduces the antioxidant capacity. For many dietary phytochemicals, direct antioxidant effects may be less important for health than other effects including effects on cell signalling or gene expression in vivo.

Highly potent delivery method of gp160 envelope vaccine combining lentivirus-like particles and DNA electrotransfer

Particulate antigen assemblies in the nanometer range and DNA plasmids are particularly interesting for designing vaccines. We hypothesised that a combination of these approaches could result in a new delivery method of gp160 envelope HIV-1 vaccine which could combine the potency of virus-like particles (VLPs) and the simplicity of use of DNA vaccines. Characterisation of lentivirus-like particles (lentiVLPs) by western blot, dynamic light scattering and electron microscopy revealed that their protein pattern, size and structure make them promising candidates for HIV-1 vaccines. Although all particles were similar with regard to size and distribution, they clearly differed in p24 capsid protein content suggesting that Rev may be required for particle maturation and Gag processing. In vivo, lentiVLP pseudotyping with the gp160 envelope or with a combination of gp160 and VSV-G envelopes did not influence the magnitude of the immune response but the combination of lentiVLPs with Alum adjuvant resulted in a more potent response. Interestingly, the strongest immune response was obtained when plasmids encoding lentiVLPs were co-delivered to mice muscles by electrotransfer, suggesting that lentiVLPs were efficiently produced in vivo or the packaging genes mediate an adjuvant effect. DNA electrotransfer of plasmids encoding lentivirus-like particles offers many advantages and appears therefore as a promising delivery method of HIV-1 vaccines. Keywords:VLP, Electroporation, Electrotransfer, HIV vaccine, DNA vaccine

Phosphorothioate backbone modifications of nucleotide-based drugs are potent platelet activators

Nucleotide-based drug candidates such as antisense oligonucleotides, aptamers, immunoreceptor-activating nucleotides, or (anti)microRNAs hold great therapeutic promise for many human diseases. Phosphorothioate (PS) backbone modification of nucleotide-based drugs is common practice to protect these promising drug candidates from rapid degradation by plasma and intracellular nucleases. Effects of the changes in physicochemical properties associated with PS modification on platelets have not been elucidated so far. Here we report the unexpected binding of PS-modified oligonucleotides to platelets eliciting strong platelet activation, signaling, reactive oxygen species generation, adhesion, spreading, aggregation, and thrombus formation in vitro and in vivo. Mechanistically, the platelet-specific receptor glycoprotein VI (GPVI) mediates these platelet-activating effects. Notably, platelets from GPVI function-deficient patients do not exhibit binding of PS-modified oligonucleotides, and platelet activation is fully abolished. Our data demonstrate a novel, unexpected, PS backbone-dependent, platelet-activating effect of nucleotide-based drug candidates mediated by GPVI. This unforeseen effect should be considered in the ongoing development programs for the broad range of upcoming and promising DNA/RNA therapeutics.

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

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 2384 Da) 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 (575 mg/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.

Potent anthelmintic activity of galloylated proanthocyanidins from shea meal (Vitellaria paradoxa)

Proanthocyanindins (PAs) from shea meal (SM), a by-product obtained after lipid extraction of the nuts, contained B-type linkages, had a high ratio of prodelphinidins (73%) and were galloylated (42%). The average polymer size was 8 flavan-3-ol subunits (≈2384 Daltons) and epigallocatechin gallate was the major subunit. Purified PA fractions from SM were tested in vitro for anthelmintic properties against gastrointestinal nematodes from ruminants (H. contortus and T. colubriformis) [1] by the larval exsheathment inhibition assay and from pigs (A. suum) by the larval migration inhibition assay. Results showed that PAs from SM have a potent anthelmintic activity against those parasites similar to white clover (Trifolium repens) flowers (WCF) [1, 2] (EC50 µg/mL; SM: 55.1, 16.5, 75.9; WCF: 37.4, 14.5, 110.1 for A. suum, H. contortus and T. colubriformis respectively). WCF PAs are constituted almost exclusively of prodelphinidin (PD) compared to SM (98% vs. 73%) but do not contained galloylated PAs. Studies [1, 2] have shown that anthelmintic activity of PAs was mainly associated with their PD ratio but our current results suggest that galloylation can be a major factor to anthelmintic activity and SM as a potential nutraceutical anthelmintic feed for controlling parasitic nematodes.

Crotalphine induces potent antinociception in neuropathic pain by acting at peripheral opioid receptors

Neuropathic pain is an important clinical problem and it is usually resistant to the current therapy. We have recently characterized a novel analgesic peptide, crotalphine, from the venom of the South American rattlesnake Crotalus durissus terrificus. In the present work, the antinociceptive effect of crotalphine was evaluated in an experimental model of neuropathic pain induced in rats by chronic constriction, of sciatic nerve. The effect of the peptide was compared to that induced by the crude venom, which confirmed that crotalphine is responsible for the antinociceptive effect of the crotalid venom on neuropathic pain. For characterization of neuropathic pain, the presence of hyperalgesia, allodynia and spontaneous pain was assessed at different times after nerve constriction. These phenomena were detected 24 h after surgery and persisted at least for 14 days. The pharmacological treatments were performed on day 14 after surgery. Crotalphine (0.2-5 mu g/kg) and the crude venom (400-1600 mu g/kg) administered p.o. inhibited hyperalgesia, allodynia and spontaneous pain induced by nerve constriction. The antinociceptive effect of the peptide and crude venom was long lasting, since it was detected up to 3 days after treatment. Intraplantar injection of naloxone (1 mu g/paw) blocked the antinociceptive effect, indicating the involvement of opioid receptors in this phenomenon. Gabapentin (200 mg/kg, p.o.), and morphine (5 mg/kg, s.c.), used as positive controls, blocked hyperalgesia and partially inhibited allodynia induced by nerve constriction. These data indicate that crotalphine induces a potent and long lasting opioid antinociceptive effect in neuropathic pain that surpasses that observed with standard analgesic drugs. (C) 2008 Elsevier B.V. All rights reserved.

Biomimetic biosensor based on lipidic layers containing tyrosinase and lutetium bisphthalocyanine for the detection of antioxidants

This paper describes the preparation of a biomimetic Langmuir-Blodgett film of tyrosinase incorporated in a lipidic layer and the use of lutetium bisphthalocyanine as an electron mediator for the voltammetric detection of phenol derivatives, which include one monophenol (vanillic acid), two diphenols (catechol and caffeic acid) and two triphenols (gallic acid and pyrogallol). The first redox process of the voltammetric responses is associated with the reduction of the enzymatically formed o-quinone and is favoured by the lutetium bisphthalocyanine because significant signal amplification is observed, while the second is associated with the electrochemical oxidation of the antioxidant and occurs at lower potentials in the presence of an electron mediator. The biosensor shows low detection limit (1.98 x 10(-6)-27.49 x 10(-6) M), good reproducibility, and high affinity to antioxidants (Km in the range of 62.31-144.87 mu M). The excellent functionality of the enzyme obtained using a biomimetic immobilisation method, the selectivity afforded by enzyme catalysis, the signal enhancement caused by the lutetium bisphthalocyanine mediator and the increased selectivity of the curves due to the occurrence of two redox processes make these sensors exceptionally suitable for the detection of phenolic compounds. (C) 2010 Elsevier B.V. All rights reserved.

Synthesis of the C11-C23 Fragment of the Potent Antitumor Agent Dictyostatin

We wish to report here our initial efforts toward the total synthesis of the potent antitumor agent dictyostatin, describing a short and efficient synthesis of the C11-C23 fragment. ( (C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Three-dimensional quantitative structure-activity relationships for a large series of potent antitubercular agents

Comparative molecular field analysis (CoMFA) studies were conducted on a series of 100 isoniazid derivatives as anti-tuberculosis agents using two receptor-independent structural data set alignment strategies: (1) rigid-body fit, and (2) pharmacophore-based. Significant cross-validated correlation coefficients were obtained (CoMFA(1), q(2) = 0,75 and CoMFA(2), q(2) = 0.74), indicating the potential of the models for untested compounds. The models were then used to predict the inhibitory potency of 20 test set compounds that were not included in the training set, and the predicted values were in good agreement with the experimental results.

Acridone alkaloids as potent inhibitors of cathepsin V

Cathepsin V is a lysosomal cysteine peptidase highly expressed in thymus, testis and corneal epithelium. Eleven acridone alkaloids were isolated from Swinglea glutinosa (Bl.) Merr. (Rutaceae), with eight of them being identified as potent and reversible inhibitors of cathepsin V (IC(50) values ranging from 1.2 to 3.9 mu M). Detailed mechanistic characterization of the effects of these compounds on the cathepsin V-catalyzed reaction showed clear competitive inhibition with respect to substrate, with dissociation constants (K(i)) in the low micromolar range (2, K(i) = 1.2 mu M; 6, K(i) = 1.0 mu M; 7, K(i) = 0.2 mu M; and 11, K(i) = 1.7 mu M). Molecular modeling studies provided important insight into the structural basis for binding affinity and enzyme inhibition. Experimental and computational approaches, including biological evaluation, mode of action assessment and modeling studies were successfully employed in the discovery of a small series of acridone alkaloid derivatives as competitive inhibitors of catV. The most potent inhibitor (7) has a K(i) value of 200 nM. (C) 2011 Elsevier Ltd. All rights reserved.

Synthesis of the Macrolactone of Migrastatin and Analogues with Potent Cell-Migration Inhibitory Activity

The synthesis of the macrolactone core of migrastatin 2, its potent anti-metastasis analogue 34, and ester derivatives 35 and 38 are reported. The approach involves the use of a dihydroxylation reaction to establish the desired C-8 stereocenter followed by a metathesis cyclization reaction. The effects of the compounds on the migration and invasion of human breast cancer cells were evaluated by using the wound-healing and the Boyden-chamber cell-migration and cell-invasion assays. The results revealed a high potency of the macrolactones 2 and 34 and the ester analogues 35 and 38, which suggests they have potential as antimetastatic agents.

Studies towards the identification of putative bioactive conformation of potent vasodilator arylidene N-acylhydrazone derivatives

In this report we disclose the synthesis, vasodilatory activity, and identification of bioactive conformation of new N-acylhydrazone and N-methyl-N-acylhydrazone derivatives, structurally designed by bioisosteric replacements of previously described cardioactive compounds LASSBio-294 and its N-methyl derivative LASSBio-785. Some of these novel derivatives presented improved vasorelaxant properties, being new cardiovascular drug candidates. (C) 2009 Elsevier Masson SAS. All rights reserved.

Effect of some antioxidants on oxidative DNA damage induced by autoxidation of microquantities of sulfite in the presence of Ni(II)/Gly-Gly-L-His

Ni(II)GGH (GGH, glycylglycyl-L-histidine) reacts rapidly with S(IV), in air-saturated solution, to produce Ni(III)GGH. A mechanism is proposed where Ni(III) oxidizes SO(3)(2-) to SO(3)(center dot-), which reacts with dissolved oxygen to produce SO(5)(center dot-), initiating radical chain reactions. DNA strand breaks and 8-oxo-7,8-dihydro-20-deoxyguanosine (8-oxodGuo) formation were observed in air-saturated solutions containing micromolar concentrations of nickel(II) and S(IV). The efficacies of melatonin, (-)-epigallocatechin-gallate (from green tea), resveratrol, tannic, and ascorbic acids in terms of their inhibitory activities of DNA strand breaks and 8-oxodGuo formation were evaluated.

Atmospheric pressure photoionization mass spectrometry as a tool for the investigation of the hydrolysis reaction mechanisms of phosphite antioxidants

The hydrolysis reaction mechanism of phosphite antioxidants is investigated by liquid chromatography-mass spectrometry (LC/MS). The phosphites were chosen because they differed in chemical structure and phosphorus content. Dopant assisted-atmospheric pressure photoionization (DA-APPI) is chosen as the ion source for (lie ionization of the compounds. [it our previous work, DA-APPI was shown to offer an attractive alternative to atmospheric pressure chemical ionization (APCI) since it provided background-ion free mass spectra and higher sensitivity [M. Papanastasiou, et al., Polymer Degradation and Stability 91 (11) (2006) 2675-2682]. In positive ion mode, the molecules are generally detected in their protonated form. In negative ion mode, the phosphites are unstable and only fragment ions are observed: these however, are characteristic of each phosphite and may be used for the identification of the analytes in complex mixtures. The analytes under investigation are exposed to accelerated humid ageing conditions and their hydrolytic pathway and stability is investigated. Different substituents around the phosphorus atom are shown to have a significant effect on the stability of the phosphites, with phenol substituents producing very hydrolytically stable structures. Alkanox P24 and PEP-36 follow a similar hydrolytic pathway via the scission of the first and then the second P-O-phenol bonds, eventually leading to the formation of phenol, Phosphorous acid and pentaerythritol as end products. HP-10 exhibits a rather different Structure and the products detected suggest scission of either the P-O-hydrocarbon or one of the P-O-phenol bonds. A phenomenon similar to that of autocatalysis is observed for all phosphites and is attributed to the formation of dialkyl phosphites as intermediate products. (C) 2008 Elsevier B.V. All rights reserved.