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1.
Int J Med Mushrooms ; 22(2): 125-131, 2020.
Article in English | MEDLINE | ID: mdl-32479001

ABSTRACT

The chemical analysis of the methanol extract of Porodaedalea chrysoloma (Fr.) Fiasson & Niemela afforded the isolation of five compounds (1-5). The first two are phenolic derivatives: methyl (E)-3-(4-methoxycar-bonylphenoxy)-acrylate (1) is a new natural product, while methyl 3-(4-methoxycarbonylphenoxy)-propionate (2) was isolated from a natural source for the first time. The triterpene steroids ergone (3), 3ß-hydroxyergosta-7,22-diene (4), and ergosterol (5) have not been previously identified in this species. The structures of the compounds were determined on the basis of NMR and MS spectroscopic analysis. The isolated fungal metabolites 1-5 were evaluated for their antioxidant activity. Compounds 1, 2, and 4 proved to possess considerable antioxidant effect in the ORAC assay with 2.21 ± 0.34, 1.58 ± 0.18, and 5.02 ± 0.47 mmol TE/g, respectively.


Subject(s)
Antioxidants/chemistry , Basidiomycota/chemistry , Fruiting Bodies, Fungal/chemistry , Phenols/chemistry , Steroids/chemistry , Triterpenes/chemistry , Agaricales , Antioxidants/isolation & purification , Cholestenones/chemistry , Cholestenones/isolation & purification , Ergosterol/chemistry , Ergosterol/isolation & purification , Magnetic Resonance Spectroscopy , Mass Spectrometry , Molecular Structure , Oxygen Radical Absorbance Capacity , Phenols/isolation & purification , Steroids/isolation & purification , Triterpenes/isolation & purification
3.
Sci Rep ; 9(1): 17002, 2019 11 18.
Article in English | MEDLINE | ID: mdl-31740690

ABSTRACT

Ecdysteroids (arthropod molting hormones) play an important role in the development and sexual maturation of arthropods, and they have been shown to have anabolic and "energizing" effect in higher vertebrates. The aim of this study was to assess ecdysteroid diversity, levels according to bird species and months, as well as to observe the molting status of hard ticks (Acari: Ixodidae) infesting the birds. Therefore, blood samples and ticks were collected from 245 birds (244 songbirds and a quail). Mass spectrometric analyses showed that 15 ecdysteroids were regularly present in the blood samples. Molting hormones biologically most active in insects (including 20-hydroxyecdysone [20E], 2deoxy-20E, ajugasterone C and dacryhainansterone) reached different levels of concentration according to bird species and season. Similarly to ecdysteroids, the seasonal presence of affected, apolytic ticks peaked in July and August. In conclusion, this study demonstrates the presence of a broad range and high concentrations of ecdysteroids in the blood stream of wild-living passerine birds. These biologically active, anabolic compounds might possibly contribute to the known high metabolic rate of songbirds.


Subject(s)
Animals, Wild/blood , Ecdysone/blood , Ecdysteroids/blood , Songbirds/blood , Animals , Animals, Wild/parasitology , Arthropods/growth & development , Arthropods/metabolism , Ecdysone/chemistry , Ecdysteroids/chemistry , Ecdysterone/analogs & derivatives , Ecdysterone/blood , Ecdysterone/chemistry , Ecdysterone/metabolism , Host-Parasite Interactions , Ixodidae/growth & development , Ixodidae/physiology , Molecular Structure , Molting , Seasons , Songbirds/classification , Songbirds/parasitology , Species Specificity
4.
Pharmaceutics ; 11(9)2019 Sep 02.
Article in English | MEDLINE | ID: mdl-31480652

ABSTRACT

To develop proper drug formulations and to optimize the delivery of their active ingredients through the dermal barrier, the Franz diffusion cell system is the most widely used in vitro/ex vivo technique. However, different providers and manufacturers make various types of this equipment (horizontal, vertical, static, flow-through, smaller and larger chambers, etc.) with high variability and not fully comparable and consistent data. Furthermore, a high amount of test drug formulations and large size of diffusion skin surface and membranes are important requirements for the application of these methods. The aim of our study was to develop a novel Microfluidic Diffusion Chamber device and compare it with the traditional techniques. Here the design, fabrication, and a pilot testing of a microfluidic skin-on-a chip device are described. Based on this chip, further developments can also be implemented for industrial purposes to assist the characterization and optimization of drug formulations, dermal pharmacokinetics, and pharmacodynamic studies. The advantages of our device, beside the low costs, are the small drug and skin consumption, low sample volumes, dynamic arrangement with continuous flow mimicking the dermal circulation, as well as rapid and reproducible results.

5.
Molecules ; 24(15)2019 Aug 05.
Article in English | MEDLINE | ID: mdl-31387269

ABSTRACT

Furocoumarins are known for their phototoxic and potential carcinogenic effects. These types of compounds have previously been reported from fennel (Foeniculum vulgare Mill.), a widely used medicinal plant and spice; however, no reliable quantitative data are available on the occurrence of these compounds in fennel fruits. For the first time, we report a comprehensive analysis of fennel fruit samples of different origins, representing a wide range of accessions for their furocoumarin content. Psoralene, 5-methoxypsoralene (bergapten), and imperatorin contents of 33 fennel samples were analyzed using a sensitive liquid chromatography-mass spectrometry (LC-MS) method. When applied at the highest therapeutic dose described in the monograph issued by the European Medicines Agency, the furocoumarin content of the fruits ranged up to 1.22 µg/d, which is below the most restrictive recommendations. Based on our findings, fennel consumption can be considered as safe, at least based on its low furocoumarin content.


Subject(s)
Foeniculum/chemistry , Furocoumarins/pharmacology , Plant Extracts/pharmacology , Ficusin/chemistry , Ficusin/pharmacology , Fruit/chemistry , Furocoumarins/chemistry , Gas Chromatography-Mass Spectrometry , Plant Extracts/chemistry , Solvents
6.
Molecules ; 24(13)2019 Jul 08.
Article in English | MEDLINE | ID: mdl-31288489

ABSTRACT

Black mulberry is a widely acknowledged ancient traditional medicine. Its extract and constituents have been reported to exert various bioactivities including antimicrobial, hypotensive, analgesic etc. effects. While black mulberry preparations are also used as antispasmodic agents in folk medicine, no related studies are available on its isolated constituents. Through an extensive chromatographic purification, seven phenolic compounds were isolated from the methanol extract of Morus nigra root bark, including morusin (1), kuwanon U (2), kuwanon E (3), moracin P (4), moracin O (5), albanol A (6), and albanol B (7). A complete NMR signal assignment of moracin P and O was achieved, and related literature errors confusing the identity of moracin derivatives are hereby clarified. Compounds 2, 5 and 7 were identified as strong antispasmodic agents on isolated rat ileum and tracheal smooth muscles, while compound 3, a methoxy derivative of 2, was inactive. Moracin O (5) inhibited the ileal and tracheal smooth muscle contractions with Emax values of 85% and 302 mg, respectively. Those actions were superior as compared with papaverine. Our findings demonstrate that prenylated arylbenzofurans, geranylated flavonoids and Diels-Alder adducts from Morus nigra are valuable antispasmodic agents. Compounds 2, 5 and 7 are suggested as marker compounds for quality control of antispasmodic mulberry preparations. Moracin O (5) is a new lead compound for related drug development initiatives.


Subject(s)
Morus/chemistry , Parasympatholytics/chemistry , Phenols/chemistry , Plant Bark/chemistry , Plant Extracts/chemistry , Plant Roots/chemistry , Benzofurans/metabolism , Drug Evaluation, Preclinical , Flavanones/metabolism , Methanol/chemistry , Parasympatholytics/pharmacology , Prenylation , Resorcinols/metabolism , Solvents/chemistry , Structure-Activity Relationship
7.
J Nat Prod ; 81(11): 2483-2492, 2018 11 26.
Article in English | MEDLINE | ID: mdl-30411614

ABSTRACT

Nine new (1-9) and two known (10, 11) jatrophane diterpenoids were isolated from the methanol extract of Euphorbia dulcis. The structure elucidation of the compounds was performed by means of extensive spectroscopic analysis, including HRESIMS, 1D (1H, JMOD), and 2D (HSQC, HMBC, 1H-1H-COSY, NOESY) NMR experiments. The absolute configuration of compound 1 was determined by single-crystal X-ray diffraction. The electrophysiological effects of compounds 1-11 and the five diterpenoids (12-16) previously isolated from Euphorbia taurinensis were investigated on stable transfected HEK-GIRK1/4 (Kir3.1/3.4) and HEK-hERG (Kv11.1) cell lines using automated patch-clamp equipment. The majority of the diterpenoids showed significant blocking activity on GIRK channels (60.8-88.7% at 10 µM), while compounds 1, 2, 9-11, 13, and 14 exerted notable inhibitory effects even at 1 µM concentration. None of the jatrophane diterpenoids interfered with the function of hERG proteins; however, compound 14 remarkably hampered K+ flow through hERG channels. These selective activities suggest that jatrophane diterpenoids may represent a group of potential lead compounds for the development of novel therapeutic agents against atrial fibrillation.


Subject(s)
Diterpenes/isolation & purification , Diterpenes/pharmacology , Euphorbia/chemistry , G Protein-Coupled Inwardly-Rectifying Potassium Channels/antagonists & inhibitors , Potassium Channel Blockers/pharmacology , Diterpenes/chemistry , Molecular Structure , Potassium Channel Blockers/chemistry
8.
Molecules ; 23(7)2018 06 23.
Article in English | MEDLINE | ID: mdl-29937511

ABSTRACT

One-hundred and sixty-eight aqueous and organic extracts of 42 selected bryophyte species were screened in vitro for antiproliferative activity on a panel of human gynecological cancer cell lines containing HeLa (cervix epithelial adenocarcinoma), A2780 (ovarian carcinoma), and T47D (invasive ductal breast carcinoma) cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and for antibacterial activity on 11 strains using the disc-diffusion method. A total of 99 extracts derived from 41 species exerted ≥25% inhibition of proliferation of at least one of the cancer cell lines at 10 µg/mL. In the cases of Brachythecium rutabulum, Encalypta streptocarpa, Climacium dendroides, Neckera besseri, Pleurozium schreberi, and Pseudoleskeella nervosa, more than one extract was active in the antiproliferative assay, whereas the highest activity was observed in the case of Paraleucobryum longifolium. From the tested families, Brachytheciaceae and Amblystegiaceae provided the highest number of antiproliferative extracts. Only 19 samples of 15 taxa showed moderate antibacterial activity, including the most active Plagiomnium cuspidatum, being active on 8 tested strains. Methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus aureus were the most susceptible to the assayed species. This is the first report on the bioactivities of these 14 species.


Subject(s)
Anti-Infective Agents/pharmacology , Antineoplastic Agents, Phytogenic/pharmacology , Bryophyta/chemistry , Plant Extracts/pharmacology , Anti-Infective Agents/chemistry , Antineoplastic Agents, Phytogenic/chemistry , Bacillus subtilis/drug effects , Bacillus subtilis/growth & development , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Epithelial Cells/drug effects , Epithelial Cells/pathology , Female , Humans , Inhibitory Concentration 50 , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/growth & development , Microbial Sensitivity Tests , Moraxella catarrhalis/drug effects , Moraxella catarrhalis/growth & development , Plant Extracts/chemistry
9.
Brain Res Bull ; 139: 269-277, 2018 05.
Article in English | MEDLINE | ID: mdl-29522862

ABSTRACT

Decreased beta-amyloid clearance in Alzheimer's disease and increased blood-brain barrier permeability in aged subjects have been reported in several articles. However, morphological and functional characterization of blood-brain barrier and its membrane transporter activity have not been described in physiological aging yet. The aim of our study was to explore the structural changes in the brain microvessels and possible functional alterations of P-glycoprotein at the blood-brain barrier with aging. Our approach included MR imaging for anatomical orientation in middle aged rats, electronmicroscopy and immunohistochemistry to analyse the alterations at cellular level, dual or triple-probe microdialysis and SPECT to test P-glycoprotein functionality in young and middle aged rats. Our results indicate that the thickness of basal lamina increases, the number of tight junctions decreases and the size of astrocyte endfeet extends with advanced age. On the basis of microdialysis and SPECT results the P-gp function is reduced in old rats. With our multiparametric approach a complex regulation can be suggested which includes elements leading to increased permeability of blood-brain barrier by enhanced paracellular and transcellular transport, and factors working against it. To verify the role of P-gp pumps in brain aging further studies are warranted.


Subject(s)
Aging/physiology , Blood-Brain Barrier/physiology , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , ATP Binding Cassette Transporter, Subfamily B, Member 1/ultrastructure , Age Factors , Animals , Area Under Curve , Blood-Brain Barrier/diagnostic imaging , Blood-Brain Barrier/metabolism , Blood-Brain Barrier/ultrastructure , Chromatography, Liquid , Glial Fibrillary Acidic Protein/metabolism , Glial Fibrillary Acidic Protein/ultrastructure , Magnetic Resonance Imaging , Male , Microdialysis , Microvessels/metabolism , Microvessels/ultrastructure , Rats , Rats, Wistar , Tandem Mass Spectrometry , Tight Junctions/metabolism , Tight Junctions/ultrastructure , Tomography, Emission-Computed, Single-Photon
10.
Drug Metab Pharmacokinet ; 32(3): 165-171, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28365301

ABSTRACT

The purpose of this study was to characterize the uptake of carnitine, the physiological substrate, and the uptake of 3-(2,2,2-trimethylhydrazinium)propionate, a consensus substrate by rat Octn2 and human OCTN2 transporters as well as to characterize drug-mediated inhibition of l-carnitine uptake by the rat and human orthologs overexpressed in CHO-K1 cells. l-carnitine and 3-(2,2,2-trimethylhydrazinium)propionate were found to be a lower affinity substrate for rat Octn2 (KM = 32.66 ± 5.11 µM and 23.62 ± 4.99 µM respectively) than for human OCTN2 (KM = 3.08 ± 0.74 µM and 7.98 ± 0.63 µM). The intrinsic clearance (CLint) value for carnitine was higher for the human than for the rat transporter (22.82 ± 5.57 ml/min*mg vs 4.008 ± 0.675 ml/min*mg). For 3-(2,2,2-trimethylhydrazinium)propionate, in contrast, the CLint value for rat Octn2 was higher than for human OCTN2 (323.9 ± 72.8 ml/min*mg vs 65.11 ± 5.33 ml/min*mg). Furthermore, many pharmacologically important drugs were shown to affect l-carnitine transport by Octn2/OCTN2. The correlation between the IC50 datasets for the rat and human transporter resulted in an r value of 0.47 (p > 0.05). However, the greatest difference was less than seven-fold and 13 of 15 compounds yielded a difference less than 3-fold. Thus, the transporters from these two species showed an overlapping but somewhat different substrate and inhibitor specificity.


Subject(s)
Carnitine/pharmacology , Methylhydrazines/pharmacology , Solute Carrier Family 22 Member 5/antagonists & inhibitors , Animals , CHO Cells , Cells, Cultured , Cricetulus , Dose-Response Relationship, Drug , Humans , Kinetics , Male , Rats , Rats, Wistar , Solute Carrier Family 22 Member 5/genetics , Solute Carrier Family 22 Member 5/metabolism , Species Specificity , Structure-Activity Relationship
11.
Fitoterapia ; 115: 69-73, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27702667

ABSTRACT

The main objective of this project was to investigate the antibacterial activity of 19 species (Juncus acutus, J. alpinoarticulatus, J. articulatus, J. compressus, J. conglomeratus, J. effusus, J. filiformis, J. gerardii, J. inflexus, J. maritimus, J. monanthos, J. squarrosus, J. tenuis, J. trifidus, Luzula campestris, L. forsteri, L. luzuloides, L. sudetica and L. sylvatica) belonging to the family Juncaceae against methicillin-resistant S. aureus (MRSA), extended-spectrum ß-lactamase (ESBL)-producing C. freundii, E. coli, E. cloacae, K. pneumoniae, and multiresistant A. baumannii and P. aeruginosa. Antibacterial susceptibilities were screened for inhibitory zones and MIC values determined by microdilution method. Among the tested extracts (n=96) 16 extracts prepared from Juncus species and 3 extracts from Luzula species showed mild to strong inhibitory activities against MRSA strains (inhibition zones=6.7mm-14.6mm; MIC values 9.75-156µg/mL). It can be concluded that Juncus and Luzula species demonstrated promising anti-MRSA effect, and J. maritimus, J. tenuis and J. gerardii considered worthy of activity-guided phytochemical investigations. The main bioactive constituents of Juncaceae species are phenanthrenes. Four phenanthrenes [juncuenin D (1), juncusol (2), dehydrojuncuenin B (3), and jinflexin B (4)] isolated previously from J. inflexus with anti-MRSA activity were investigated by LC-MS in extracts proved to be active in antimicrobial test.


Subject(s)
Anti-Bacterial Agents/chemistry , Magnoliopsida/chemistry , Phenanthrenes/chemistry , Plant Extracts/chemistry , Anti-Bacterial Agents/isolation & purification , Magnoliopsida/classification , Methicillin-Resistant Staphylococcus aureus/drug effects , Microbial Sensitivity Tests , Phenanthrenes/isolation & purification
12.
In Vivo ; 30(5): 663-9, 2016.
Article in English | MEDLINE | ID: mdl-27566088

ABSTRACT

BACKGROUND/AIM: Nitric oxide (NO) pathway plays a major role in the development and advancement of inflammation. We aimed to design a study and investigate its feasibility to show the changes of L-arginine, asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA), which are important regulators of the NO pathway. PATIENTS AND METHODS: Concentrations of L-arginine, ADMA and SDMA were measured by liquid chromatography-tandem mass spectrometry. Seventeen septic survival patients were enrolled and blood samples were obtained on the first, third and fifth day after the diagnosis of sepsis. Sixteen non-septic matched controls were recruited. RESULTS: ADMA levels on admission correlated well with sequential organ failure assessment (SOFA) score. During the follow-up, L-arginine/ADMA ratio increased significantly from day 1 to day 3 (p=0.005), then decreased from day 3 to day 5 (p=0.023). CONCLUSION: This study design seems feasible to investigate changes of L-Arginine, ADMA and SDMA in sepsis survival patients.


Subject(s)
Arginine/analogs & derivatives , Arginine/blood , Sepsis/blood , Aged , Chromatography, Liquid , Female , Humans , Inflammation/blood , Inflammation/pathology , Male , Metabolic Networks and Pathways , Middle Aged , Nitric Oxide/blood , Sepsis/pathology , Tandem Mass Spectrometry
13.
J Nat Prod ; 79(8): 1990-2004, 2016 08 26.
Article in English | MEDLINE | ID: mdl-27441737

ABSTRACT

GIRK channels are activated by a large number of G protein-coupled receptors and regulate the electrical activity of neurons, cardiac atrial myocytes, and ß-pancreatic cells. Abnormalities in GIRK channel function have been implicated in the pathophysiology of neuropathic pain, drug addiction, and cardiac arrhythmias. In the heart, GIRK channels are selectively expressed in the atrium, and their activation inhibits pacemaker activity, thereby slowing the heart rate. In the present study, 19 new diterpenes, falcatins A-S (1-19), and the known euphorprolitherin D (20) were isolated from Euphorbia falcata. The compounds were assayed on stable transfected HEK-hERG (Kv11.1) and HEK-GIRK1/4 (Kir3.1 and Kir3.4) cells. Blocking activity on GIRK channels was exerted by 13 compounds (61-83% at 10 µM), and, among them, five possessed low potency on the hERG channel (4-20% at 10 µM). These selective activities suggest that myrsinane-related diterpenes are potential lead compounds for the treatment of atrial fibrillation.


Subject(s)
Diterpenes , Euphorbia/chemistry , G Protein-Coupled Inwardly-Rectifying Potassium Channels/drug effects , Potassium Channel Blockers , Animals , Diterpenes/chemistry , Diterpenes/classification , Diterpenes/isolation & purification , Diterpenes/pharmacology , G Protein-Coupled Inwardly-Rectifying Potassium Channels/classification , Heart , Membrane Potentials/drug effects , Molecular Structure , Neurons/metabolism , Potassium Channel Blockers/pharmacology , Receptors, G-Protein-Coupled
14.
J Pharm Biomed Anal ; 130: 301-317, 2016 Oct 25.
Article in English | MEDLINE | ID: mdl-27321822

ABSTRACT

Extracts of milk thistle (Silybum marianum, Asteraceae) have been recognized for centuries as remedies for liver and gallbladder disorders. The active constituents of milk thistle fruits are flavonolignans, collectively known as silymarin. Flavonolignans in S. marianum are structurally diverse, 23 constituents have been isolated from purple- and white-flowering variants. Flavonolignans have a broad spectrum of bioactivities and silymarin has been the subject of intensive research for its profound pharmacological activities. Silymarin is extracted from the seeds, commercialized in standardized form, and widely used in drugs and dietary supplements. The thorough analysis of silymarin, its constituents and silymarin-containing products has a key role in the quality control of milk thistle-based products. Due to the low concentration of analytes, especially pharmacological and pharmacokinetic studies require more and more selective and sensitive, advanced techniques. The objective of the present review is to summarize the recent advances in the chemical analysis of S. marianum extracts, including the chemical composition, isolation and identification of flavonolignans, sample preparation, and methods used for qualitative and quantitative analysis. Various analytical approaches have been surveyed, and their respective advantages and limits are discussed.


Subject(s)
Flavonolignans/analysis , Plant Extracts/analysis , Silybum marianum , Silymarin/analysis , Animals , Chromatography, Thin Layer/methods , Chromatography, Thin Layer/trends , Flavonolignans/chemistry , Humans , Magnetic Resonance Spectroscopy/methods , Silybum marianum/chemistry , Plant Extracts/chemistry , Seeds/chemistry , Silymarin/chemistry , Spectrophotometry, Ultraviolet/methods , Spectrophotometry, Ultraviolet/trends
15.
Sci Rep ; 6: 23390, 2016 Mar 21.
Article in English | MEDLINE | ID: mdl-26996354

ABSTRACT

Ecdysteroids are important hormones that regulate moulting in arthropods. Three-host ixodid ticks normally moult to the next stage after finishing their blood meal, in the off-host environment. Presumably, three-host ticks that feed on the blood of insectivorous vertebrate hosts can be exposed to high levels of exogenous ecdysteroids causing them to initiate apolysis (the first step of moulting) on the vertebrate host. The aim of the present study was to investigate whether ticks undergo apolysis on insectivorous song birds, and if this phenomenon is associated with the seasonal variation in the availability of moths and with the presence of naturally acquired ecdysteroids in avian blood. During a triannual survey, 3330 hard tick larvae and nymphs were collected from 1164 insectivorous song birds of 46 species. A noteworthy proportion of ticks, 20.5%, showed apolysis. The occurrence of apolytic ticks on birds was correlated with the known seasonality of lepidopteran caterpillars. In addition, 18 blood samples of tick-infested birds were analysed with liquid chromatography - tandem mass spectrometry. Eight samples contained ecdysteroids or their derivatives, frequently in high concentrations, and the presence of these was associated with tick apolysis. In conclusion, naturally acquired ecdysteroids may reach high levels in the blood of insectivorous passerine birds, and will affect ticks (feeding on such blood) by shortening their parasitism.


Subject(s)
Ecdysteroids/blood , Molting , Songbirds/parasitology , Ticks/growth & development , Animals , Ecdysteroids/chemistry , Lepidoptera/parasitology , Seasons , Songbirds/blood , Ticks/parasitology
16.
Neuroendocrinology ; 93(2): 90-105, 2011.
Article in English | MEDLINE | ID: mdl-20938166

ABSTRACT

Alzheimer disease is characterized by accumulation of ß-amyloid (Aß) and cognitive dysfunctions linked to early loss of cholinergic neurons. As estrogen-based hormone replacement therapy has beneficial effects on cognition of demented patients, and it may prevent memory impairments, we investigated the effect of estrogen-pretreatment on Aß-induced cholinergic neurodegeneration in the nucleus basalis magnocellularis (NBM). We tested which Aß species induces the more pronounced cholinotoxic effect in vivo. We injected different Aß assemblies in the NBM of mice, and measured cholinergic cell and cortical fiber loss. Spherical Aß oligomers had the most toxic effect. Pretreatment of ovariectomized mice with estrogen before Aß injection decreased cholinergic neuron loss and partly prevented fiber degeneration. By using proteomics, we searched for proteins involved in estrogen-mediated protection and in Aß toxicity 24 h following injection. The change in expression of, e.g., DJ-1, NADH ubiquinone oxidoreductase, ATP synthase, phosphatidylethanolamine-binding protein 1, protein phosphatase 2A and dimethylarginine dimethylaminohydrolase 1 support our hypothesis that Aß induces mitochondrial dysfunction, decreases MAPK signaling, and increases NOS activation in NBM. On the other hand, altered expression of, e.g., MAP kinase kinase 1 and 2, protein phosphatase 1 and 2A by Aß might increase MAPK suppression and NOS signaling in the cortical target area. Estrogen pretreatment reversed most of the changes in the proteome in both areas. Our experiments suggest that regulation of the MAPK pathway, mitochondrial pH and NO production may all contribute to Aß toxicity, and their regulation can be prevented partly by estrogen pretreatment.


Subject(s)
Amyloid beta-Peptides/toxicity , Basal Nucleus of Meynert/drug effects , Cell Death/drug effects , Cholinergic Fibers/drug effects , Estradiol/pharmacology , Neuroprotective Agents/pharmacology , Amyloid beta-Peptides/administration & dosage , Amyloid beta-Peptides/chemistry , Animals , Basal Nucleus of Meynert/pathology , Cholinergic Fibers/pathology , Female , Mice , Mice, Inbred C57BL , Microinjections , Particle Size , Proteomics/methods , Signal Transduction/drug effects
17.
Vet Microbiol ; 147(1-2): 96-102, 2011 Jan 10.
Article in English | MEDLINE | ID: mdl-20599331

ABSTRACT

Methicillin and oxacillin-hydrolyzing enzymes of 6 borderline methicillin-resistant and 1 methicillin-resistant Staphylococcus aureus strains isolated from human clinical samples and 4 borderline methicillin-resistant S. aureus strains isolated from bovine mastitis were investigated. As previous studies suggested the involvement of an additional enzyme besides the penicillinase BlaZ in the determination of borderline resistance, we analyzed the expressed extracellular and membrane-bound ß-lactamases with 2-D gel electrophoresis and mass spectrometry. Our analysis showed that the penicillin-hydrolyzing BlaZ alone was responsible for the hydrolysis of both methicillin and oxacillin. All supernatant and membrane fractions contained the same enzyme with slight sequence variations. The size and pI of the proteins were also variable, probably due to spontaneous hydrolysis and/or posttranslational modifications. Interestingly, we found also cytotoxins and other virulence factors in some nitrocefin-hydrolyzing dots, suggesting that those proteins might have a role in the reduction of local antibiotic concentration.


Subject(s)
Penicillins/pharmacology , Proteomics , Staphylococcus aureus/enzymology , Staphylococcus aureus/isolation & purification , beta-Lactamases/isolation & purification , beta-Lactamases/metabolism , Animals , Anti-Bacterial Agents/pharmacology , Cattle , Cephalosporins/metabolism , Drug Resistance, Bacterial , Female , Humans , Membrane Proteins/metabolism , Methicillin-Resistant Staphylococcus aureus/enzymology , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Penicillinase/metabolism , Staphylococcal Infections/microbiology , Staphylococcus aureus/drug effects
18.
Eur Neuropsychopharmacol ; 20(2): 96-111, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20015620

ABSTRACT

Recently, several attempts have been made to describe changes related to certain anxiety states in the proteome of experimental animal models. However, these studies are restricted by limitations regarding the number and correct identification of separated proteins. Moreover, the application of a systems biology approach to discover the molecular mechanisms of anxiety requires genetically homogenous inbred animal models. Therefore, we developed a novel mouse model of anxiety using a combination of crossbreeding (inbred for 35 generations) and behavioral selection. We found significant changes in 82 proteins in the total brain proteome compared to the control proteome. Thirty-four of these proteins had been previously identified in other anxiety, depression or repeated psychosocial stress studies. The identified proteins are associated with different cellular functions, including synaptic transmission, metabolism, proteolysis, protein biosynthesis and folding, cytoskeletal proteins, brain development and neurogenesis, oxidative stress, signal transduction. Our proteomics data suggest that alterations in serotonin receptor-associated proteins, in the carbohydrate metabolism, in the cellular redox system and in synaptic docking are all involved in anxiety.


Subject(s)
Anxiety/metabolism , Brain/metabolism , Disease Models, Animal , Nerve Tissue Proteins/metabolism , Proteome/metabolism , Animals , Exploratory Behavior , Hybridization, Genetic , Maze Learning , Mice , Mice, Inbred Strains , Models, Molecular , Species Specificity
19.
J Bacteriol ; 190(19): 6448-57, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18689470

ABSTRACT

Upon induction, Bacillus megaterium 216 produces the bacteriocin megacin A-216, which leads to lysis of the producer cell and kills B. megaterium and a few other bacterial species. The DNA region responsible for megacinogeny was cloned in B. megaterium. The nucleotide sequence of a 5,494-bp-long subfragment was determined, and the function of the genes on this fragment was studied by generating deletions and analyzing their effects on MegA phenotypes. An open reading frame (ORF) encoding a 293-amino-acid protein was identified as the gene (megA) coding for megacin A-216. BLAST searches detected sequence similarity between megacin A-216 and proteins with phospholipase A2 activity. Purified biologically active megacin A-216 preparations contained three proteins. Mass spectrometry analysis showed that the largest protein is the full-length translation product of the megA gene, whereas the two shorter proteins are fragments of the long protein created by cleavage between Gln-185 and Val-186. The molecular masses of the three polypeptides are 32,855, 21,018, and 11,855 Da, respectively. Comparison of different megacin preparations suggests that the intact chain as well as the two combined fragments can form biologically active megacin. An ORF located next to the megA gene and encoding a 91-amino-acid protein was shown to be responsible for the relative immunity displayed by the producer strain against megacin A-216. Besides the megA gene, at least two other genes, including a gene encoding a 188-amino-acid protein sharing high sequence similarity with RNA polymerase sigma factors, were shown to be required for induction of megacin A-216 expression.


Subject(s)
Bacillus megaterium/genetics , Bacillus megaterium/metabolism , DNA, Bacterial/genetics , Megacins/biosynthesis , Chromatography, Gel , Cloning, Molecular , DNA, Bacterial/chemistry , Electrophoresis, Polyacrylamide Gel , Models, Genetic , Molecular Sequence Data , Open Reading Frames/genetics , Sequence Analysis, DNA , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
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