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ObjectiveAltering dysbiotic gut flora through synbiotic supplementation has recently been recognized as a potential treatment strategy to reduce the levels of gut-derived uremic toxins and decrease inflammation. Assessing its efficacy and safety has been the main goal of our randomized, double-blind, placebo-controlled study.MethodsA total of 34 nondialyzed chronic kidney disease patients, aged ≥18 years, with an estimated glomerular filtration rate between 15 and 45 mL/minute, were randomized either to an intervention group (n = 17), receiving synbiotic (Lactobacillus acidophilus, Lactobacillus casei, and Bifidobacterium lactis, 32 billion colony forming units per day plus 3.2 g of inulin), or control group (n = 17), receiving placebo during 12 weeks. The impact of treatment on the dynamic of serum levels of gut-derived uremic toxins, total serum indoxyl sulfate, p-cresyl sulfate, and trimethylamine N-oxide, was defined as the primary outcome of the study. Secondary outcomes included changes in the stool microbiome, serum interleukin-6 levels, high-sensitivity C-reactive protein, estimated glomerular filtration rate, albuminuria, diet, gastrointestinal symptom dynamics, and safety. Serum levels of uremic toxins were determined using ultraperformance liquid chromatography. The stool microbiome analysis was performed using the 16S ribosomal ribonucleic acid gene sequencing approach.ResultsSynbiotic treatment significantly modified gut microbiome with Bifidobacteria, Lactobacillus, and Subdoligranulum genera enrichment and consequently reduced serum level of indoxyl sulfate (ΔIS –21.5% vs. 5.3%, P

Intensive use of pesticides requires innovative approaches for their removal from the environment. Here we report the method for degradation of dimethoate in water using non-thermal plasma needle and analyze kinetics of dimethoate removal and possible degradation pathways. The effects of dimethoate initial concentration, plasma treatment time, Argon flow rate and the presence of radical promoters on the effectiveness of proposed method are evaluated. With argon flow rate of 0.5 slm (standard litres per minute) 1 × 10−4 M dimethoate can be removed within 30 min of treatment. Using UPLC analysis it was confirmed that one of the decomposition products is dimethoate oxo-analogue omethoate, which is in fact more toxic than dimethoate. However, the overall toxicity of contaminated water was reduced upon the treatment. The addition of H2O2 as a free radical promoter enhances dimethoate removal, while K2S2O8 results with selective conversion to omethoate. Using mass spectrometry in combination with the theoretical calculations, possible degradation pathways were proposed. The feasibility of the proposed method for dimethoate degradation in real water samples is confirmed. The proposed method is demonstrated as a highly effective approach for dimethoate removal without significant accumulation of undesirable toxic products and secondary waste. © 2019 Elsevier Ltd

Yellow gentian (Gentiana lutea ssp. symphyandra (Murb.) Hayek) is a high-mountainous perennial spontaneously growing on meadows and open slopes of the Eastern part of the Alps and the Balkan Peninsula. While the excessive exploitation endangered its survival in the nature in many European countries, the orientation to its large-scale production enables its protection at natural stands and satisfaction of increasing market demands for its roots, a highly-valuable herbal drug (Gentianae radix). During the six-year field trial established with Yellow gentian nursery plants on black water-air permeable and biodegradable film, in dry farming conditions of Mountain Tara (Serbia), the influence of a sigle basal application of farm yard manure and mineral fertilizer, at different planting densities (11.1, 13.3 and 16 plants m −2 ) on produced yield (roots), has been investigated. Single dose fertilization positively influenced the yields but did not provide optimal supplies for cultivated crop in the second part of experiment. It depended on crop age, planting density but also the climatic conditions. In the second part of plant production period, particulary in denser establishemnts, additional fertilization should be applied. Providing the appropriate amounts of fertilizers, Yellow gentian can be successfully grown even in the densest planting model (16 plants m −2 ), which is quite important in respect to the economic feasibility of cultivation. Similar yields achieved in mineral and organic treatments (4.51 kg m −2 and 4.85 kg m -2 of fresh root, respectively), suggest the roots might be successfully produced in both, conventional and organic cultivation model. In attempt to estimate impact of fertilization treatments on chemical quality of produced raw material (Gentianae radix) the content of several pharmacological constituents (loganic acid, swertiamarin, gentiopicroside, sweroside, amarogentin and isogentisin) was evaluated; gentiopicroside and loganic acid were the most dominant ones, regadless the fertilization, whereas the content of isogentisin was significantly increased in both, organic and mineral fertilization model, and content of sweroside, only in mineral model. With regard to the safety of produced raw material, the contents of biogenic (Fe, Mn, Zn, Cu) and non-biogenic (Pb) trace elements were analyzed; all trace elements were within the safty limits except the Cd content which slightly exceeded the limit. © 2019 Elsevier B.V.

Lipid oxidation that occurs in different types of food can cause alterations in nutritional qualities, flavour, texture and shelf life of foods. Furthermore, high temperature cooking of protein-rich food can lead to formation of heterocyclic aromatic amines capable of compromising the integrity of DNA molecules. To reduce these harmful effects, research has been focused on investigating plants as a source of potential natural food additives and preservatives. Thus, the aim of this study was to estimate antioxidant and antigenotoxic activities of 50% ethanolic-aqueous root and leaf extracts of the medicinal plant, Gentiana lutea. Antioxidative effect was investigated using the DPPH assay, while antigenotoxicity against the mutagen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) was determined using Salmonella Typhimurium TA 1535 in the SOS/umuC assay. Leaf extract showed high antioxidative effect with the ability to neutralize up to 87% of free radicals at 400 µg mL-1. Antigenotoxicity testing revealed that both extracts exhibited remarkable genoprotective activity against PhIP-induced DNA damage, with the highest inhibition levels being 70% and 85% for root and leaf extracts, respectively. Results obtained are encouraging and suggest further research of G. lutea extracts as potential food preservatives and additives in improving food quality and human health.

AlCl3-Catalyzed {[}3 + 2] dipolar cycloaddition of the N,N'-cyclic azomethine imines to the acryloylferrocene enabling access to the series of 5-substituted 6-ferrocenoyl tetrahydropyrazolo {[}1,2-a]pyrazol-1(5H)-ones. This facile methodology shows high substituent tolerance. Furthermore, easy chromatographic separations afford isolation of the pure diastereoisomers. Optimized reaction conditions, spectroscopic and electrochemical characteristics of the reaction products are provided. The X-ray structural analyses of three cycloadducts were done and obtained results were compared with properties of reported N,N'-bicyclic systems those displayed conformational similarity. Antibacterial activities of all products against two Gram-positive and two Gram-negative bacterial strains were evaluated by the experimental methods. (c) 2018 Elsevier B.V. All rights reserved.

Medicinal plant Gentiana lutea is considered as an official drug for gastrointestinal disorders in many pharmacopoeias. Its uncontrolled overexploitation led to the protection regime and encouraged development of in vitro culture. The aim of this work was to chemically characterize root and leaf methanol extracts of plant grown in plantation and in vitro conditions, and to determine their antigenotoxicity against heterocyclic aromatic amines IQ and PhIP, the food-borne mutagens that are formed during high temperature cooking of protein-reach foods. High yields and growth ratios were determined for in vitro plants. Higher content of polyphenols and flavonoids were determined in aerial parts, while UPLC-MS/MS analysis pointed at the richness of in vitro grown shoot extract (GLvS) in active constituents, and high amounts of gentiopicroside in all tested extracts. Notable amounts of sweroside were detected in plantation root extract (GLR) and in GLvS, and of loganic acid in plantation leaf extract (GLL) and GLvS. Two experimental models for genotoxicity/antigenotoxicity study, i.e. SOS/umuC test with metabolic activation (addition of rat liver S9 fraction) and alkaline comet assay on hepatocellur carcinoma HepG2 cells indicated dual effects: genotoxic of high and antigenotoxic of lower non-genotoxic doses. While in vitro extracts were genotoxic in both models, plantation extracts were active only in SOS/umuC with S9. In contrast, inhibition of genotoxicity was observed in both models for all extracts (up to 83 %). Results of DPPH assay indicated that antioxidativity could be responsible for antigenotoxic properties. In conclusion, genoprotective effect encourages further investigation of antigenotoxicity, while high growth ratio and richness of GLvS in active compounds justify the use of in vitro cultivation method.

Food mutagens formed from amino acids during heating of meat have the potential to induce serious consequences on human health. As a result, the identification of naturally occurring, genoprotective agents, is of great importance. The aim of this study was to chemically characterize a root and leaf extracts of Gentiana lutea and to investigate the antigenotoxic effects of extracts and pure constituents (gentiopicroside and mangiferin). Antigenotoxic effects were shown for combinations with the food borne mutagens IQ and PhIP using hepatoma HepG2 cells. Furthermore, their antioxidant activity and their capacity to modulate Nrf2 expression and affect the glutathione redox status were tested. Chemical analyses showed that the most abundant constituents found in root extract are gentiopicroside and sweroside. On the other hand, homoorientin and isovitexin were the dominant ones in leaf extract. Strong genoprotective activities of all tested compounds against both mutagens were observed in alkaline comet assays (up to 77% of tail intensity inhibition, p < 0.001). The protection against glutathione depletion was partially due to the radical scavenging activity and up-regulation of Nrf2 expression by the substances. The results of this study strongly encourage further investigations of the antimutagenic properties of G. lutea.

During high-temperature cooking of protein rich foods, especially meat and fish, heterocyclic aromatic amines can be formed. These amines are a class of potent mutagens that can cause alterations in the structure of DNA and chromosomes. In recent decades, research has been focused on investigating plants and their phytochemicals as potential antimutagens. The aim of this study was to examine the anti-genotoxic effect of methanolic root and leaf extracts of Gentiana lutea against the food mutagens 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) produced in thermally processed meat. To determine the protective potential of extracts, the alkaline comet assay was applied. The results obtained indicated strong anti-genotoxic effect of both extracts against the tested mutagens. The highest inhibition of IQ-induced genotoxicity was recorded for leaf extract (72%). Regarding PhiP, root extract achieved inhibition of 80% of DNA damage, so was more successful than leaf extract. The data obtained in this study stimulates further research of G. lutea extracts and its constituents as potential dietary supplements in improving human health. © Published under licence by IOP Publishing Ltd. Conference of 60th International Meat Industry Conference, MEATCON 2019 ; Conference Date: 22-25 September 2019; Conference Code:153290

The photoluminescence (PL) quenching mechanism of UV light and air-exposed amorphous thin films of 4,4-bis(2,2-diphenylvinyl)-1,1-biphenyl (DPVBi), a well-known hole-transport material used in organic light-emitting diodes, is studied. Thin films of DPVBi are stable when exposed to UV light in vacuum but tend to degrade if oxygen is present simultaneously. This is evident from the changes in UV-vis absorption spectra of the latter, showing that degradation rate of DPVBi films is linearly proportional to both oxygen concentration and UV light intensity. Mass spectrometry study of such films revealed a number of different oxygen-containing molecules and fragments of DPVBi thus confirming apparent photo-oxidation process. Also, DFT study of molecular DPVBi with and without oxygen was carried out, the IR spectra calculated for the lowest energy molecules found and the results are compared with the experiment. The most sensitive to photo-oxidation is DPVBi photoluminescence, which decays exponentially with respect to the concentration of photo-oxidized DPVBi molecules (impurities). The PL quantum yield of DPVBi thin film drops to a half of its original value for 0.2% of the impurities present, at which point an average distance between DPVBi molecules (the donors) and photo-oxidized DPVBi species (acceptors) is an order of magnitude larger than the separation between two adjacent molecules. This implies a need for a long-range Forster energy transfer, which we rule out based on the lack of a donor-acceptor spectral overlap. The apparent discrepancy can be removed by postulating exciton self-diffusion in DPVBi thin films, for which there is supporting evidence in existing literature. (C) 2015 Elsevier B.V. All rights reserved.

In the current study, the biocontrol potential of a novel strain Bacillus sp. PPM3 isolated from marine sediment from the Red Sea in Hurghada, Egypt is recognized. This novel strain was selected out of 32 isolates based on its ability to suppress the growth of four plant pathogenic fungi: Aspergillus flavus, Fusariurn graminearum, Mucor sp. and Alternaria sp. The new marine strain was identified and characterized by phenotypic and molecular approaches. The culture filtrate of Bacillus sp. PPM3 suppressed the growth and spore germination of all tested fungi in vitro with the highest value of inhibition reported for Mucor sp. (97.5%). The antifungal effect of the culture filtrate from the strain PPM3 was due to production of highly stable secondary metabolites resistant to extreme pH, temperature and enzymatic treatments. A PCR analysis confirmed the expression of genes involved in the synthesis of antifungal lipopeptides: iturin, bacillomycin D, mycosubtilin and surfactin. In a greenhouse experiment strain PPM3 effectively reduced disease incidence of F. graminearum in maize plants and displayed additional plant growth stimulating effect. The results show that novel marine strain PPM3 could have a potential in commercial application as biocontrol agent for treatment of various plant diseases caused by soil-borne and postharvest pathogenic fungi.

A series of ferrocenes which contain dinitrogen-fused pyrazolidinone ring were synthesized from acryloylferrocene (4) and N,N′‑cyclic azomethine imines (3). Novel 5‑aryl‑6‑ferrocenoyltetrahydropyrazolo[1,2‑a]pyrazol‑1(5H)-ones were obtained as mixtures of two diastereoisomers (trans and cis) which were separated and isolated as pure substances. Ortho-substituted N,N′‑cyclic azomethine imines 5-oxo-2-(2,4,6-trimethylbenzylidene)pyrazolidin-2-ium-1-ide (3e) and 2-(2-methoxybenzylidene)-5-oxopyrazolidin-2-ium-1-ide (3f) reacted stereoselectively affording only trans-6-ferrocenoyl-5-mesityltetrahydropyrazolo[1,2-a]pyrazol-1(5H)-one (5e) and 6-ferrocenoyl-5-(2-methoxyphenyl)tetrahydropyrazolo[1,2-a]pyrazol-1(5H)-one (5f). Ferrocenyl derivatives were screened for in vitro antioxidant and antifungal activities and excellent DPPH and ABTS radicals scavenging activity was observed with majority of tested 5‑aryl‑6‑ferrocenoyltetrahydropyrazolo[1,2‑a]pyrazol‑1(5H)-ones. Several tested compounds showed selective scavenging properties neutralizing ABTS•+ radical cations in contrast to inactivity toward DPPH[rad] radicals. Trans-5-aryl-6-ferrocenoyltetrahydropyrazolo[1,2-a]pyrazol-1(5H)-ones 5b, 5c, 5d, 5j as well as cis-6-ferrocenoyl-5-(p-tolyl)tetrahydropyrazolo[1,2-a]pyrazol-1(5H)-one (6d) displayed fungal growth inhibition at low concentration against C. albicans and/or A. brasiliensis. Molecular docking studies revealed that the cis-6-ferrocenoyl-5-(4-nitrophenyl)tetrahydropyrazolo[1,2-a]pyrazol-1(5H)-one (6l) and cis-6-ferrocenoyl-5-(naphthalen-2-yl)tetrahydropyrazolo[1,2-a]pyrazol-1(5H)-one (6n) have potential to become lead molecules in drug discovery process. © 2018 Elsevier Inc.

UV-C irradiation is widely used in the food industry. However, the health effects from dietary exposure to the irradiated pesticide residues retained in foodstuffs are underestimated. In this study, technical chlorpyrifos (TCPF) and its oil in water (EW) and emulsifiable concentrate (EC) formulations were irradiated by UV-C, and their photodegradation products were subjected to toxicity assessment, including determination of acetylcholinesterase (AChE) activity, genotoxicity and oxidative stress using human blood cells as a model system. Toxicity studies were performed using the chlorpyrifos concentrations in the range of those proposed as the maximum residue levels in plant commodities. TCPF, EW and EC photodegradation products induced DNA damage and oxidative stress, and their genotoxicity did not decrease as a function of irradiation time. Irradiated TCPF and EC are more potent AChE inhibitors than irradiated EW. Accordingly, the application of UV-C irradiation must be considered when processing the plants previously treated with chlorpyrifos formulations. © 2018 Elsevier Ltd

BACKGROUND: Fruit wines are well known for their profound health-promoting properties including both enzyme activations and inhibitions. They may act preventive in regard to diabetes melitus and other chronic diseases. OBJECTIVES: Potential α-glucosidase inhibitory activity of fruit wines made from blueberry, black chokeberry, blackberry, raspberry and sour cherry was the subject of this study. METHOD: In order to increase the alcohol content due to enriched extraction of total phenolics, sugar was added in the fruit pomace of the half of the examined fruit wine samples. RESULTS: Compared with acarbose used as a positive control (IC50 = 73.78 µg/mL), all fruit wine samples exhibited higher α-glucosidase inhibitory activity. Indeed, blueberry wine samples stood out, both prepared with IC50 = 24.14 µg/mL, lyophilised extract yield 3.23% and without IC50 = 46.39 µg/mL, lyophilised extract yield 2.89% and with addition of sugar before fermentation. Chlorogenic acid predominantly contributed to α-glucosidase inhibitory activity of the blueberry, black chokeberry and sour cherry wine samples. However, ellagic acid, a potent α-glucosidase inhibitor possessing a planar structure, only slightly affected the activity of the blueberry wine samples, due to the lower concentration. In addition to this, molecular docking study of chlorogenic acid pointed out the importance of binding energy (-8.5 kcal/mol) for the inhibition of the enzyme. CONCLUSION: In summary, fruit wines made from blueberry should be primarily taken into consideration as a medicinal food targeting diabetes mellitus type 2 in the early stage, if additional studies would confirm their therapeutic potential for the control of postprandial hyperglycemia. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

The present paper deals with the investigations of optimal conditions for the myeloperoxidase (MPO) mediated oxidation of chlorpyrifos, azinphos-methyl and phorate, organophosphorous pesticides (OPs) containing phosphorothionate group, from thio- to oxo-forms, in the presence of hydrogen peroxide. The aim of the work was to apply this oxidation method in the AChE based bioanalytical tests for OPs determination. The maximum concentration of oxo-forms for all tested pesticides was achieved after 10 min incubation of OPs in 50 mM phosphate buffer (pH 6.0) with 100 nM MPO in the presence of 50 mu M H(2)O(2). Optimal temperature for obtaining maximal concentration of oxo-forms was 37 degrees C. Only the parent compounds and their oxo-forms were identified chromatographically in the OPs samples after their exposure to MPO. Moreover, no hydrolysis products were detected in the time interval of 1 h after the MPO catalyzed reaction was stopped by catalase. The efficiency of OPs transformation from thio- to oxo-forms was measured using acethylcholinesterase (AChE) test, by comparison of percent of AChE inhibition before and after exposure to the oxidized sample. (C) 2011 Elsevier Inc. All rights reserved.

For the first time, complexes of Zn(II), Cd(II) and Co(II) (1–3) with N-benzyloxycarbonylglycine have been synthesized and characterized. The complexes adopt tetrahedral, pentagonal-bipyramidal and octahedral geometry, respectively. The structure of the polymeric cadmium complex was resolved by single crystal X-ray analysis. The cadmium ion has a distorted pentagonal-bipyramidal coordination formed by two water molecules and two N-benzyloxycarbonylglycinato ligands (N-Boc) coordinated in different fashions, one as bidentate and the second connecting three cadmium atoms. In a rather complicated 2D supramolecular structure, the phenyl rings interact mutually exclusively by the CH⋯π interactions. Investigation of the antimicrobial activity of the obtained complexes and N-benzyloxycarbonylglycine revealed that the ligand does not inhibit the growth of Candida albicans, whereas the newly synthesized complexes suppress the growth of this human fungal pathogen.

The extracellular nucleotides act as neurotransmitters and signaling molecules in CNS, binding to a P2X and P2Y receptors. Their concentration regulates a cascade of membrane ecto enzymes, including the ecto-nucleotide triphosphate diphosphohydrolases (E-NTPDases). In many neuropathological conditions, such as neuroinflammatory, epilepsy, depression and migraine, altering of E-NTPDase activity was observed. The objective of this study was to investigate whether Gentiana lutea (G. lutea) extracts affect E-NTPDase activity and which of their constituents (loganic acid, gentiopicroside, isovitexin, amarogentin and isogentisin) exert inhibitory activity. The constituent's concentration in the extracts was determined by ultra performance liquid chromatography coupled with mass spectrometry (UPLC-MS). Extracts and constituents were tested with E-NTPDase displayed on the rat synaptosomal membrane as well as by molecular docking study. Ethanol water extract (50%, v/v) exerted significant level of inhibition (52%) at concentration of 200 mg mL(-1). By inhibition studies with single constituents about 30% inhibition was achieved in any case, thus the model of one substrate acting on two enzymes was used to determine IC50 values. Molecular docking study revealed amarogentin, isovitexin and isogentisin dimer as the potent E-NTPDase inhibitors with the binding energies ranging from -9.4 to -10 kcal mol(-1) versus -8.0 kcal mol(-1) for ATP. Presence of isogentisin only in ethanol water extracts may explain their better inhibitory acitivities. Findings of this study are useful from the perspective of safety of products based on G. lutea extracts, while investigated constituents belong to secoiridoids and xanthones class of compounds could be considered as a source of potential E-NTPDase inhibitors.

Silver doped fluorapatite nanopowders were synthesised by neutralization method, which consists of dissolving Ag2O in solution of HF and H3PO4 and addition to suspension of Ca(OH)(2). The powder XRD, SEM and FTIR studies indicated the formation of a fluorapatite nanomaterials with average length of the particles is about 80 nm and a width of about 15 nm. The FUR studies show that carbonate content in samples is very small and carbonte ions substitute both phosphate and hydroxyl groups in the crystal structure of samples, forming AB-type fluorapatite. Antibacterial studies have demonstrated that all Ag+-doped fluorapatite samples exhibit bactericidal effect against pathogens: Staphylococcus aureus, Micrococcus luteus and Kllebsiela pneumoniae. Antibacterial activity increased with the increase of Ag+ in the samples. The atomic force microscopy studies revealed extensive damage to the bacterial cell envelops in the presence of AW-doped fluorapatite particles which may lead to their death. The synthesized Ag+-doped fluorapatite nanomaterials are promising as antibacterial biomaterials in orthopedics and dentistry. (C) 2015 Elsevier B.V. All rights reserved.

Accumulation of intracellular sorbitol due to increased aldose reductase (ALR2) activity has been implicated in the development of various secondary complications of diabetes. Thus, ALR2 inhibition could be an effective strategy in the prevention or delay of certain diabetic complications.Gentiana luteagrows naturally in the central and southern areas of Europe. Its roots are commonly consumed as a beverage in some European countries and are also known to have medicinal properties. The water, ethanol, methanol, and ether extracts of the roots ofG. luteawere subjected toin vitrobioassay to evaluate their inhibitory activity on the ALR2. While the ether and methanol extracts showed greater inhibitory activities against both rat lens and human ALR2, the water and ethanol extracts showed moderate inhibitory activities. Moreover, the ether and methanol extracts ofG. lutearoots significantly and dose-dependently inhibited sorbitol accumulation in human erythrocytes under high glucose conditions. Molecular docking studies with the constituents commonly present in the roots ofG. luteaindicate that a secoiridoid glycoside, amarogentin, may be a potential inhibitor of ALR2. This is the first paper that showsG. luteaextracts exhibit inhibitory activity towards ALR2 and these results suggest thatGentianaor its constituents might be useful to prevent or treat diabetic complications.

The aim of this study was to investigate the inhibitory activity of Gentiana lutea extracts on the enzyme myeloperoxidase (MPO), as well as the antioxidant activity of these extracts and their correlation with the total polyphenol content. Extracts were prepared using methanol (100%), water and ethanol aqueous solutions (96, 75, 50 and 25% v/v) as solvents for extraction. Also, isovitexin, amarogentin and gentiopicroside, pharmacologically active constituents of G. lutea were tested as potential inhibitors of MPO. Antioxidant activity of extracts was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging test and also using cyclic voltammetry (CV). Among all extracts, the antioxidant capacity of 50% ethanol aqueous extract was the highest, both when measured using the DPPH test, with IC50 = 20.6 mu g/ml, and when using CV. Also, 50% ethanol extract, showed the best inhibition of MPO activity in comparison with other extracts. In the group of the selected G. lutea constituents, gentiopicroside has proved to be the strongest inhibitor of MPO, with IC50 = 0.8 mu g/ml. Also, the concentration of G. lutea constituents were determined in all extracts, using Ultra Performance Liquid Chromatography (UPLC). (C) 2012 Elsevier B.V. All rights reserved.

Multiple sclerosis (MS) is a debilitating inflammatory disease of the central nervous system (CNS) characterized by local destruction of the insulating myelin surrounding neuronal axons. With more than 200 million MS patients worldwide, the absence of treatments that prevent progression or induce repair poses a major challenge. Anti-inflammatory therapies have met with limited success only in preventing relapses. Previous screening of human serum samples revealed natural IgM antibodies that bind oligodendrocytes and promote both cell signaling and remyelination of CNS lesions in an MS model involving chronic infection of susceptible mice by Theiler’s encephalomyelitis virus and in the lysolecithin model of focal demyelination. This intriguing result raises the possibility that molecules with binding specificity for oligodendrocytes or myelin components may promote therapeutic remyelination in MS. Because of the size and complexity of IgM antibodies, it is of interest to identify smaller myelin-specific molecules with the ability to promote remyelination in vivo. Here we show that a 40-nucleotide single-stranded DNA aptamer selected for affinity to murine myelin shows this property. This aptamer binds multiple myelin components in vitro. Peritoneal injection of this aptamer results in distribution to CNS tissues and promotes remyelination of CNS lesions in mice infected by Theiler’s virus. Interestingly, the selected DNA aptamer contains guanosine-rich sequences predicted to induce folding involving guanosine quartet structures. Relative to monoclonal antibodies, DNA aptamers are small, stable, and non-immunogenic, suggesting new possibilities for MS treatment.

Immobilization of divalent Nickel cations provides a tool for affinity purification of proteins containing hexahistidine tags. During experiments to generate single-stranded DNA aptamers to immobilized proteins we inadvertently identified DNA sequences with affinity for Nickel-nitrilotriacetic acid (Ni(2+)-NTA) magnetic beads. Analysis of these aptamers revealed that affinity for the Ni(2+)-NTA support requires only single-stranded sequences with multiple adenosine residues. Bound nucleic acids can be eluted with imidazole. A single-stranded dA(20) affinity tag (but not other homopolymer sequences) is sufficient for immobilization of double-stranded DNA PCR products on Ni(2+)-NTA magnetic beads. Addition of an rA(20) sequence to an RNA transcript allowed its affinity capture on Ni(2+)-NTA magnetic beads, suggesting an approach for purification of poly(A) mRNA.

Herbal preparation Chlamyfin was investigated for its total polyphenol content, 2,2-diphenyl-1- picrylhydrazyl (DPPH) scavenging activity, and anti-inflammatory and genotoxic properties. A high total polyphenol content provided evidence of high DPPH radical scavenging activity (IC50 = 4.96 ± 0.23 μg/ml). Analysis of the electrochemical behavior of Chlamyfin indicated high reducing ability, i.e., high antioxidant capacity, in agreement with the DPPH test. Analysis of myeloperoxidase (MPO) inhibition by Chlamyfin suggested anti-inflammatory action (IC50 values of 5.40 μg/ml and 4.45 μg/ml for an incubation time of 10 and 30 min, respectively). For genotoxic assessment, oxidative stress was induced by irradiation of peripheral whole blood with gamma-radiation in vitro. In the presence of Chlamyfin, reduced incidence of micronuclei without disturbance to the proliferative potential of cells was evidenced in both irradiated and unirradiated samples, indicating its genoprotective properties. It was shown that Chlamyfin, in addition to its bactericidal effect, also possesses strong antioxidant, anti-inflammatory and anti-genotoxic properties.