Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 21
Filter
Add more filters










Publication year range
1.
Environ Monit Assess ; 195(5): 570, 2023 Apr 14.
Article in English | MEDLINE | ID: mdl-37059862

ABSTRACT

This study was undertaken with the aim of selecting one or more lichen species that are the most suitable for transplant-based surveys of air pollution in Tunisia, in areas where the local native lichen vegetation is scanty or missing at all. To this purpose, four epiphytic (tree inhabiting) lichen species (Evernia prunastri, Flavoparmelia caperata, Parmotrema perlatum, Ramalina farinacea) were collected from the Babouch forests, a remote and unpolluted area of NW Tunisia, and analyzed for their content of potentially toxic elements (PTEs), namely Al, As, Cd, Cr, Cu, Fe, Ni, Pb, Sb, and Zn, by ICP-MS. Moreover, also the physiological status of the lichen samples was evaluated by measuring their chlorophyll content, photosynthetic efficiency, and spectral reflectance. The results indicated a remarkable contribution of airborne soil and dust particles to the total PTE content, especially for the foliose species F. caperata and P. perlatum. The fruticose lichens E. prunastri and R. farinacea had a lower and similar content of PTEs, and hence were regarded as more suitable to be used in transplant studies, since are able to detect even minimal accumulation amounts. All lichen species were healthy, as emerged from the analysis of physiological parameters.


Subject(s)
Air Pollutants , Air Pollution , Lichens , Metals, Heavy , Air Pollutants/analysis , Environmental Monitoring/methods , Tunisia , Air Pollution/analysis , Metals, Heavy/analysis
2.
Lett Appl Microbiol ; 76(4)2023 Apr 03.
Article in English | MEDLINE | ID: mdl-36928103

ABSTRACT

Actinomycetes produce secondary metabolites with many bioactivities such as antimicrobial, which can be useful as alternatives against resistant bacterial strains. Therefore, the screening of new habitats is likely to provide new strains with high potential. In this work, the antimicrobial capacity was used to select Streptomyces sp. strains isolated from Raf Raf forest (Tunisia). From the strain displaying higher activity, FR7, an ethyl acetate extract was prepared under optimized culturing conditions (10 days at 30°C in ISP2 medium with initial pH 8), showing significant antimicrobial activity against Micrococcus luteus and Staphylococcus aureus (MIC = 5 µg ml-1), and Listeria monocytogenes and Pseudomonas aeruginosa (MIC = 20 µg ml-1). The extract displayed strong DPPH radical scavenging activity (IC50 = 1.3 µg ml-1) and protection of yeast cells from H2O2-induced oxidative stress determined by flow cytometry with dichlorofluorescein diacetate. The crude extract showed the presence of polyketides, with methylsalicylic acid as moiety, a large and diverse group of secondary metabolites with a wide range of bioactivities, including antioxidant and antibacterial. Based on 16S RNA gene sequences, strain FR7 was identified as belonging to genus Streptomyces with high resemblance to S. iakyrus. Streptomyces sp. FR7 has great potential as a source of antibacterial and antioxidant metabolites.


Subject(s)
Anti-Infective Agents , Streptomyces , Antioxidants/pharmacology , Antioxidants/metabolism , Soil , Streptomyces/metabolism , Hydrogen Peroxide/metabolism , Microbial Sensitivity Tests , Anti-Bacterial Agents/metabolism , Anti-Infective Agents/metabolism , Forests
3.
Nephrol Ther ; 14(3): 153-161, 2018 May.
Article in English | MEDLINE | ID: mdl-29325696

ABSTRACT

Renal allograft loss is most often a chronic process, irrespective of the mechanism at stake. In this prospective study, we studied the expression of epithelial to mesenchymal transition (EMT) markers vimentin and ß-catenin by immunohistochemistry in the surveillance biopsy and measured the mRNA encoding vimentin (VIM), CD45, GAPDH and uroplakin 1a (UPK) by quantitative PCR in urinary cells in 75 renal transplant patients. The aim is to establish a simple screening test for chronic renal allograft dysfunction. We found that the value of the mRNA of vimentin and CD45 relative to the uroplakin 1a (UPK) mRNA is correlated with the score in vimentin immunostaining in routine biopsies. These biomarkers could be used as a noninvasive tool to monitor the renal graft fibrogenesis. This test could be used for early detection of fibrotic diseases of the kidney transplant.


Subject(s)
Biomarkers/metabolism , Epithelial-Mesenchymal Transition/genetics , Graft Rejection/diagnosis , Kidney Transplantation/adverse effects , RNA, Messenger/urine , Adult , Allografts , Female , Graft Rejection/metabolism , Humans , Immunohistochemistry , Kidney/metabolism , Kidney/pathology , Leukocyte Common Antigens/metabolism , Male , Mass Screening/methods , Middle Aged , Prospective Studies , ROC Curve , Real-Time Polymerase Chain Reaction , Uroplakin Ia/metabolism , Vimentin/metabolism , beta Catenin/metabolism
4.
Chem Biodivers ; 14(1)2017 Jan.
Article in English | MEDLINE | ID: mdl-27514988

ABSTRACT

In the current study, the phenolic composition, antioxidant and antimicrobial activities of extracts from Rubus ulmifolius Schott leaves harvested in four localities (Sejnen, Tabarka, Faija and Ain drahem) in Tunisia were investigated for the first time. Great differences were found for the chemical composition, total phenol contents and biological activities among the evaluated extracts. HPLC analysis of methanolic extracts showed that the dominant compounds were kaempferol 3-O-rutinoside and naringenine. In addition, significant correlations were observed between antioxidant activities and phenolic contents. In fact, leaves collected from Sejnen presented higher total phenol content (53.32 mg GAE/g DW) and antioxidant activities (IC50 = 39.40 mg/l) than the others samples. All extracts showed significant antimicrobial activity against six used bacteria with the inhibition zones diameters and minimal inhibitory concentration values were in the range of 8 - 16 mm and 6.25 - 25 mg/ml, respectively. The highest antimicrobial activities were recorded in Sejnen extract against Gram-positive bacteria.


Subject(s)
Anti-Bacterial Agents/pharmacology , Plant Extracts/chemistry , Rubus/chemistry , Anti-Bacterial Agents/isolation & purification , Antioxidants/analysis , Antioxidants/pharmacology , Bacteria/drug effects , Microbial Sensitivity Tests , Phenols/analysis , Phenols/pharmacology , Plant Extracts/pharmacology , Tunisia
5.
J Oleo Sci ; 65(7): 533-42, 2016 Jul 01.
Article in English | MEDLINE | ID: mdl-27321118

ABSTRACT

The quality of olive oil is defined as a combination of characteristics that significantly determine its acceptance by consumers. This study was carried out to compare sensorial and chemical characteristics of sixty 'Chétoui' extra virgin olive oils (EVOOc) samples from six northern areas in Tunisia (Tebourba (EVOOT); Other regions (EVOON): Mornag, Sidi Amor, El Kef, Béjà and Jendouba). Trained panel taste detected ten sensory attributes. EVOOT and EVOON were defined by 'tomato' and 'grass/ leave notes, respectively. Twenty one volatile compounds from EVOOc were extracted and identified by Headspace Solid-Phase Microextraction followed by Gas Chromatography- Flame Ionization Detector. Principal component and cluster analysis of all studied parameters showed that EVOOT differed from EVOON. Sensory and volatile profiles of EVOOc revealed that the perception of different aromas, in monovarietal olive oil, was the result of synergic effect of oils' various components, whose composition was influenced by the geographical growing area.


Subject(s)
Odorants/analysis , Oils, Volatile/isolation & purification , Oils, Volatile/pharmacology , Olea/chemistry , Olea/classification , Olive Oil/chemistry , Olive Oil/pharmacology , Taste/drug effects , Chromatography, Gas , Humans , Oils, Volatile/chemistry , Olive Oil/isolation & purification , Principal Component Analysis , Solid Phase Microextraction , Tunisia
6.
Appl Biochem Biotechnol ; 176(3): 938-46, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25894950

ABSTRACT

The transesterification of soybean lecithin with ethyl esters of polyunsaturated fatty acids (eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) using immobilized lipase from Rhizomucor miehei was tested in the presence or absence of organic solvent (hexane) and additives (urea with Ca(2+) or Mg(2+)). The reaction was carried out at a water concentration of 4 % and ethyl ester to phospholipid mass ratio of 3:1. After 24 h of reaction without solvent or additive, fatty acid incorporation reached 29.1 % and thereafter increased only slightly. After 48 h, incorporation was highest in the presence of Mg(2+), urea, and solvent. After 72 h, it was highest with Mg(2+) and urea in the presence or absence of solvent (56.8 and 45.7 %, respectively). Incorporation of EPA and DHA was thus initially fast without solvent and additive, but was increased after prolonged reaction in the presence of Mg(2+) and urea with or without solvent. These results are innovative and promising since they show that immobilized Rhizomucor miehei lipase has potential as a biocatalyst for interesterification reactions without solvent.


Subject(s)
Docosahexaenoic Acids/chemistry , Eicosapentaenoic Acid/chemistry , Glycine max/chemistry , Lecithins/pharmacology , Lipase/metabolism , Rhizomucor/enzymology , Urea/pharmacology , Calcium/pharmacology , Esterification , Esters , Hexanes/pharmacology , Magnesium/pharmacology , Solvents/pharmacology , Water/analysis
7.
FEMS Microbiol Ecol ; 91(1): 1-13, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25764537

ABSTRACT

Adding inorganic P- and N-fixing legumes to semi-arid grasslands can increase forage yield, but soil nutrient concentrations and plant cover may also interact to modify soil fungal populations, impacting short- and long-term forage production. We tested the effect of plant assemblage (seven native grasses, seven native grasses + the domesticated N-fixing legume Medicago sativa, seven native grasses + the native N-fixing legume Dalea purpurea or the introduced grass Bromus biebersteinii + M. sativa) and soil P concentration (addition of 0 or 200 P2O5 kg ha(-1) at sowing) on the diversity and community structure of arbuscular mycorrhizal (AM) fungi and total fungi over two consecutive years, using 454-pyrosequencing of 18S rDNA and ITS amplicons. Treatment effects were stronger in the wet year (2008) than the dry year (2009). The presence of an N-fixing legume with native grasses generally increased AM fungal diversity, while the interaction between soil P concentration and plant assemblage modified total fungal community structure in 2008. Excluding interannual variations, which are likely driven by moisture and plant productivity, AM fungal communities in semi-arid grasslands appear to be primarily affected by plant assemblage composition, while the composition of other fungi is more closely linked to soil P.


Subject(s)
Biodiversity , Fungi/classification , Mycorrhizae/classification , Soil/chemistry , Base Sequence , DNA, Ribosomal , Grassland , Medicago sativa , Mycorrhizae/genetics , Nitrogen Fixation , Phosphorus/chemistry , Plants , Poaceae/microbiology , RNA, Ribosomal, 18S/genetics , Sequence Analysis, RNA , Soil Microbiology
8.
World J Microbiol Biotechnol ; 29(12): 2233-8, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23749246

ABSTRACT

The transesterification of soybean lecithin with methyl esters of EPA and DHA in an organic solvent (hexane) using various commercially available lipases was studied. Lipases produced by Candida antarctica, Pseudomonas fluorescens, Burkholderia cepacia, Mucor miehei, Thermomyces lanuginosus and Rhizomucor miehei were compared, in the absence or presence of histidine, arginine, urea, Ca²âº, Mg²âº, or a combination of urea and divalent cations (additives at 5 % of the total lipid mass). Transesterification using the R. miehei enzyme reached 11.32 and 12.30 % in the presence of Ca²âº or Mg²âº respectively, and 8.58 and 9.31 % when urea was also added. These were the greatest degrees of transesterification obtained. The results suggest the potential use of this immobilized lipase as a catalyst for interesterification reactions in organic solvent systems with low water content.


Subject(s)
Amines/metabolism , Cations, Divalent/metabolism , Fatty Acids, Omega-3/metabolism , Glycine max/chemistry , Lecithins/chemistry , Lipase/metabolism , Bacterial Proteins/metabolism , Biocatalysis , Burkholderia cepacia/enzymology , Candida/enzymology , Esterification , Esters , Fungal Proteins/metabolism , Methylation , Pseudomonas fluorescens/enzymology
9.
J Nat Prod ; 75(1): 2-8, 2012 Jan 27.
Article in English | MEDLINE | ID: mdl-22220635

ABSTRACT

The new chromophenazines A-F [9-methyl-5-(3'-methylbut-2'-enyl)-5H-benzo[a]phenazin-7-one (1a), 9-methyl-5-(3'-methylbut-2'-enyl)-7-oxo-5,7-dihydrobenzo[a]phenazine-1-carboxylic acid (1b), 5-(3'-methylbut-2'-enyl)-7-oxo-5,7-dihydrophenazine-1-carboxamide (2), 3-benzoyl-5-(3'-methylbut-2'-enyl)-5,10-dihydrophenazine-1-carboxylic acid (5a), 3,7-dibenzoyl-5-(3'-methylbut-2'-enyl)-5,10-dihydrophenazine-1-carboxylic acid (5b), and 3,7-dibenzoyl-5-(3'-methylbut-2'-enyl)-5,10-dihydrophenazine-1-carboxamide (5c)], together with phenazine-1-carboxylic acid, 1-phenazinecarboxamide, 1-phenazinol, tryptophol, and anthranilic acid, were isolated from Streptomyces sp. Ank 315. The structures of the new compounds were established on the basis of spectroscopic data, 1D NOE, 2D NMR, and ESIMS measurements and comparison with literature values.


Subject(s)
Anti-Infective Agents/isolation & purification , Phenazines/isolation & purification , Streptomyces/chemistry , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Bacillus subtilis/drug effects , Candida albicans/drug effects , Escherichia coli/drug effects , Microbial Sensitivity Tests , Molecular Structure , Mucor/drug effects , Nuclear Magnetic Resonance, Biomolecular , Phenazines/chemistry , Phenazines/pharmacology , Staphylococcus aureus/drug effects
10.
J Food Sci ; 76(2): C224-30, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21535739

ABSTRACT

Essential oils of Juniperus phoenicea L. leaves cultivated in 3 regions, Korbos, Matmata, and Tabarka of Tunisia were obtained by hydrodistillation (HD), steam distillation (SD), and Soxhlet (SH) extraction methods. The essential oils were analyzed and quantified by capillary gas chromatography using flame ionization detection (GC-FID) and mass spectrometry (GC-MS). The highest yield was observed in HD process (1.12%). Tabarka essential oil provided the best yield 0.79% compared to other regions. December month SD essential oil was the highest in oxygenated monoterpenes (52.7%). Nevertheless, SH essential oil showed a higher content in sesquitepenes hydrocarbons (64.5%). α-Terpinol (25.5%) was the main oxygenated component in Matmata juniper essential oil, extracted by SD. Moreover, the antioxidant activity of essential oils was evaluated using ABTS assays. The strongest antioxidant activity (IC(50) = 22.6 ± 0.7 mg/L) was obtained by the Matmata (October 2007) SD essential oil.


Subject(s)
Juniperus/chemistry , Oils, Volatile/isolation & purification , Plant Extracts/analysis , Plant Leaves/chemistry , Volatile Organic Compounds/analysis , Antioxidants/analysis , Distillation/methods , Flame Ionization , Gas Chromatography-Mass Spectrometry , Geography , Monoterpenes/analysis , Seasons , Tunisia
11.
Obes Facts ; 4(1): 45-52, 2011.
Article in English | MEDLINE | ID: mdl-21372610

ABSTRACT

OBJECTIVE: The aim of this study was to test the utility of preferred walk-run transition speed (WRTS) in exercise training adjunct to dietary restriction for obesity management in healthy obese women. MATERIALS AND METHODS: 37 obese women (age: 35 ± 9 years, body mass index (BMI): 34.9 ± 4.6 kg/m(2)) were assigned to an intervention pilot study during 6 months of restricted diet alone (RD) followed by 6 months of RD combined with WRTS (RD and WRTS) as a training exercise. Body mass, waist circumference (WC), fat mass (FM), fat free mass (FFM), active cell mass (ACM), fasting glucose, serum lipids (triacylglycerol (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), apo-lipoproteins A1 (ApoA1) and B (ApoB)], leptin and insulin concentrations, and HOMA-IR were assessed at baseline (T0), at the end of the RD alone (T1), and at the end of the RD and WRTS programme (T2). RESULTS: Mean weight loss was 8.6 ± 4.9 kg and 2.2 ± 2.9 kg for (T0-T1) and (T1-T2), respectively. Significant BMI and WC reductions were reported at T1 and T2. FM decreased significantly both with RD and with RD and WRTS training whereas FFM and ACM increased with RD and WRTS training only. TG decreased significantly with the two phases of the programme. A significant increase in HDL-C, and a decrease in LDL-C and TC/HDL-C ratio were noticed with RD and WRTS training. Heart rate monitored in training improved significantly after RD and WRTS training. A significant relationship (r = 0.542, p < 0.02) was demonstrated between reductions in serum leptin and insulin concentrations observed with both RD and WRTS training. CONCLUSION: The addition of WRTS training to RD promoted a greater reduction in body mass, WC, FM, leptin and insulin concentrations, improved metabolic and cardiovascular risk factors, and enhanced cardiovascular fitness.


Subject(s)
Diet, Reducing , Energy Metabolism/physiology , Obesity/therapy , Running/physiology , Walking/physiology , Acceleration , Adult , Female , Humans , Middle Aged , Physical Education and Training/methods , Pilot Projects , Prospective Studies , Treatment Outcome , Young Adult
12.
J Econ Entomol ; 104(1): 188-93, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21404857

ABSTRACT

Embryonated eggs of Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) genetic sexing strain (GSS), VIENNA 8 were treated with low concentrations of five disinfectants-formaldehyde, iodine, sodium hypochlorite, peracetic acid, and quaternary ammonium--for decontamination and egg hatch improvement. The newly laid eggs were successfully treated with formaldehyde at 100 ppm for 1 min with 74.2% hatching and with quaternary ammonium at 150 ppm for 1 and 2 min with 70.4 and 69% hatching, respectively. Increased formaldehyde concentration may have affected the embryos, because it resulted in a decrease in the hatching percentage. However, egg viability was not impaired and hatch was not affected by quaternary ammonium treatment compared with controls and eggs treated with other disinfectants. Quaternary ammonium shows promise for decontaminating eggs and improving egg hatch.


Subject(s)
Animal Husbandry , Ceratitis capitata , Disinfectants , Ovum , Pest Control, Biological , Animals , Female , Male , Pupa
13.
Clin Neurol Neurosurg ; 112(10): 849-52, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20691532

ABSTRACT

OBJECTIVE: The aim of our study was to investigate the association of HLA-DRB1 and -DQB1 alleles with multiple sclerosis (MS) in a Tunisian population and their effect on age at onset and disease severity. METHODS: 58 MS patients and 105 healthy controls were genotyped for HLA class II alleles by PCR-SSP technique. RESULTS: An association of MS with HLA-DRB1*15 was found (14.7% vs 3.8%, OR (95% CI)=4.34 (1.69-11.39), p(c)=2.5×10(-3)) after Bonferroni's correction. Moreover, the DRB1*15-DQB1*06 (13.8% vs 2.8%, OR (95% CI)=5.44 (1.92-17.41), p(c)=1.1×10(-3)) and DRB1*04-DQB1*04 (8.6% vs 1.9%, OR (95% CI)=4.86 (1.36-21.62), p(c)=0.028) haplotypes were found to confer a susceptibility to multiple sclerosis. CONCLUSION: To our knowledge, this is the first study performed to analyze the association of HLA-DRB1/DQB1 alleles on MS susceptibility in Tunisia. The modern Tunisian gene pool shows some degree of heterogeneity and reflects a significant gene flow from Mediterranean regions.


Subject(s)
Genes, MHC Class II/genetics , Multiple Sclerosis/genetics , Adolescent , Adult , Age of Onset , Case-Control Studies , Female , Gene Frequency , Genetic Predisposition to Disease , HLA-DQ Antigens/genetics , HLA-DQ beta-Chains , HLA-DR Antigens/genetics , HLA-DRB1 Chains , Haplotypes , Histocompatibility Testing , Humans , Male , Middle Aged , Multiple Sclerosis/epidemiology , Multiple Sclerosis/pathology , Tunisia/epidemiology , Young Adult
14.
J Sci Food Agric ; 90(3): 462-70, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20355069

ABSTRACT

BACKGROUND: Juniperus phoenicea is an important medicinal plant. In the present study, essential oils (18 samples) from leaves and berries of Juniperus phoenicea L. (Cupressaceae), obtained by various drying methods and in different collection months, were analysed by gas chromatography-mass spectrometry and also evaluated for in vitro antimicrobial and antioxidant activities. Correlations were studied between antimicrobial activity and the chemical composition of essential oils. RESULTS: Sixty-seven compounds were identified in essential oils, representing 97.7-100%. Essential oils were dominated by monoterpenes and sesquiterpenes, which presented 35.0-93.3% and 6.7-62.0%, respectively, depending of organ, season and drying method. Antimicrobial tests showed that essential oils strongly inhibited the growth of Gram-positive microorganisms and Mucor ramamnianus, but was inactive against Gram-negative strains. Antioxidant activity was tested using the ABTS radical-scavenging assay. Most samples showed good activity (the best IC(50) = 41.7 + or - 1.5 mg L(-1)). CONCLUSIONS: It could be concluded that drying of leaves of J. phoenicea in the sun and berries in oven-drying was more suitable and was recommended for obtaining higher essential oil yield, but for a higher percentage of some special components such as alpha-pinene and delta-3-carene shade-drying was more suitable.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antifungal Agents/pharmacology , Antioxidants/pharmacology , Juniperus/chemistry , Oils, Volatile/pharmacology , Plant Extracts/pharmacology , Anti-Bacterial Agents/analysis , Antifungal Agents/analysis , Antioxidants/analysis , Bacteria/drug effects , Desiccation , Fruit , Mucor/drug effects , Oils, Volatile/analysis , Plant Extracts/chemistry , Plant Leaves , Seasons
15.
J Food Sci ; 74(7): M364-71, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19895482

ABSTRACT

GC-FID and GC-MS analysis of essential oils of Juniperus phoenicea resulted in the identification of 30 compounds, representing more than 98% of the total composition. alpha-pinene (55.7% and 80.7%), delta-3-carene (10.7% and 4.5%), and gamma-cadinene (2.9% and 5.1%) were the main components, respectively, in leaves and berries essential oil. Extracts of J. phoenicea were obtained by different extraction solvents: methanol, ethanol, ethyl acetate, and dichloromethane and evaluated composition for polyphenols (gallic acid equivalent 52 to 217 g/kg), tannins (catechin equivalent 6.5 to 60.2 g/kg), antocyanins (cyanidin equivalent 84 to 373 mg/kg), and flavonoids (quercetin equivalent 6.4 to 29.3 g/kg). The samples (essential oils and extracts) were subjected to a screening for their antioxidant activity by using DPPH and ABTS assays; antimicrobial activity was tested with 6 bacteria (3 Gram-positive and 3 Gram-negative), 1 yeast, and 2 fungi. The strongest antioxidant activity was obtained by the methanolic extract (IC(50)= 6.5 +/- 0.3 mg/L). Flavonoids are likely to contribute to the antifungal activity against Saccharomyces cerevisiae. Correlations were studied between chemical composition and antioxidant and antimicrobial activities.


Subject(s)
Anti-Infective Agents/pharmacology , Antioxidants/pharmacology , Juniperus/chemistry , Oils, Volatile/chemistry , Oils, Volatile/pharmacology , Plant Extracts/chemistry , Plant Extracts/pharmacology , Anti-Infective Agents/chemistry , Anti-Infective Agents/isolation & purification , Antioxidants/chemistry , Antioxidants/isolation & purification , Distillation , Flame Ionization , Flavonoids/analysis , Free Radical Scavengers/chemistry , Free Radical Scavengers/isolation & purification , Free Radical Scavengers/pharmacology , Fruit/chemistry , Fungi/drug effects , Gas Chromatography-Mass Spectrometry , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Microbial Sensitivity Tests , Oils, Volatile/isolation & purification , Phenols/analysis , Plant Extracts/isolation & purification , Plant Leaves/chemistry , Polyphenols , Species Specificity , Tannins/analysis , Yeasts/drug effects
16.
Phytochemistry ; 70(11-12): 1435-41, 2009.
Article in English | MEDLINE | ID: mdl-19766274

ABSTRACT

An antiplasmodial bioguided investigation of the EtOAc extract of the aerial parts of Teucrium ramosissimum led to isolation and identification of three sesquiterpenoids, teucmosin, 4alpha-hydroxy-homalomenol C, 1beta,4beta,7alpha-trihydroxy-8,9-eudesmene and two trinorsesquiterpenoids, 4beta-hydroxy-11,12,13-trinor-5-eudesmen-1,7-dione and 1beta,4beta-dihydroxy-11,12,13-trinor-8,9-eudesmen-7-one together with five known sesquiterpenoids, oplopanone, homalomenol C, oxo-T-cadinol, 1beta,4beta,6beta-trihydroxyeudesmane, 1beta,4beta,7alpha-trihydroxyeudesmane and four flavonoids, 5-hydroxy-7,4'-dimethoxyflavone, salvigenin, genkwanin and cirsimaritin. The structures and the relative stereochemistry were elucidated by extensive spectroscopic studies including 1D and 2D NMR and mass spectrometry (MS). Homalomenol C, 4beta-hydroxy-11,12,13-trinor-5-eudesmen-1,7-dione, oxo-T-cadinol and 1beta,4beta,6beta-trihydroxyeudesmane displayed a significant in vitro antiplasmodial activity against Plasmodium falciparum with IC(50) values ranging from 1.2 to 5.0 microg/ml. Furthermore, no cytotoxicity was observed upon the human diploid lung cell line MRC-5 for these compounds.


Subject(s)
Antimalarials/isolation & purification , Plant Extracts/isolation & purification , Plasmodium falciparum/drug effects , Sesquiterpenes/isolation & purification , Teucrium/chemistry , Animals , Antimalarials/chemistry , Antimalarials/pharmacology , Cell Line , Humans , Lung/cytology , Lung/drug effects , Molecular Structure , Plant Components, Aerial , Plant Extracts/chemistry , Plant Extracts/pharmacology , Sesquiterpenes/chemistry , Sesquiterpenes/pharmacology
17.
Cell Calcium ; 45(2): 144-54, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18947868

ABSTRACT

The human sarco/endoplasmic reticulum (ER) Ca(2+)ATPase 3 (SERCA3) gene gives rise to SERCA3a-3f isoforms, the latter inducing ER stress in vitro. Here, we first demonstrated the co-expression of SERCA3a, -3d and -3f proteins in the heart. Evidence for endogenous proteins was obtained by using isoform-specific antibodies including a new SERCA3d-specific antibody, and either Western blotting of protein lysates or immunoprecipitation of membrane proteins. An immunolocalization study of both left ventricle tissue and isolated cardiomyocytes showed a distinct compartmentalization of the SERCA3 isoforms, as a uniform distribution of SERCA3a was detected while -3d and -3f isoforms were observed around the nucleus and in close vicinity of plasma membrane, respectively. Second, we studied their expressions in failing hearts including mixed (MCM) (n=1) and idiopathic dilated (IDCM) cardiomyopathies (n=4). Compared with controls (n=5), similar expressions of SERCA3a and -3d mRNAs were observed in all patients. In contrast, SERCA3f mRNA was found to be up-regulated in failing hearts (125+/-7%). Remarkably, overexpression of SERCA3f paralleled an increase in ER stress markers including processing of X-box-binding protein-1 (XBP-1) mRNA (176+/-24%), and expression of XBP-1 protein and glucose-regulated protein (GRP)78 (232+/-21%). These findings revisit the human heart's Ca(2+)ATPase system and indicate that SERCA3f may account for the mechanism of ER stress in vivo in heart failure.


Subject(s)
Cell Compartmentation , Endoplasmic Reticulum/enzymology , Endoplasmic Reticulum/pathology , Heart Failure/enzymology , Sarcoplasmic Reticulum Calcium-Transporting ATPases/metabolism , Adult , Cell Line , DNA-Binding Proteins/metabolism , Endoplasmic Reticulum Chaperone BiP , Gene Expression Profiling , Gene Expression Regulation, Enzymologic , Heart Failure/genetics , Heat-Shock Proteins , Humans , Intracellular Space/enzymology , Isoenzymes/genetics , Isoenzymes/metabolism , Middle Aged , Molecular Chaperones , Myocardium/enzymology , Myocardium/pathology , Myocytes, Cardiac/enzymology , RNA, Messenger/genetics , RNA, Messenger/metabolism , Regulatory Factor X Transcription Factors , Sarcoplasmic Reticulum Calcium-Transporting ATPases/genetics , Transcription Factors/metabolism , Transcription, Genetic , X-Box Binding Protein 1
18.
Platelets ; 18(7): 543-9, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17957572

ABSTRACT

Platelet Ca(2+) homeostasis is controlled by a multi-Ca(2+)ATPase system including two PMCA (plasma membrane Ca(2+)ATPase) and seven SERCA (sarco/endoplasmic reticulum Ca(2+)ATPase) isoforms. Previous studies have shown similar platelet Ca(2+) abnormalities in diabetic and hypertensive patients, including an increase in intracellular [Ca(2+)](I), a possible modulation of PMCA activity and increased PMCA tyrosine phosphorylation. Very recently, we found that platelets from diabetic patients also exhibited increased PMCA4b expression. In the present study we looked for further similarities between diabetic and hypertensive patients. We first confirmed a decrease in Ca(2+)ATPase activity (mean 55 + 7%) in mixed platelet membranes isolated from 10 patients with hypertension compared with those from 10 healthy controls. In addition, the decreased Ca(2+)ATPase activity correlated with the DBP of the different patients, as expected for PMCA activity. Second, we performed a pilot study of six hypertensives to examine their expressions of PMCA and SERCA mRNA and proteins. Like the diabetic patients, 100% of hypertensives were found to present a major increase in PMCA4b expression (mean value of 218 +/- 21%). We thus determined that platelets from diabetic and hypertensive patients showed similar increased PMCA4b isoform. Since increased PMCA4b expression was recently found to be associated with a perturbation of megakaryocytopoiesis, these findings may also point to an abnormality in platelet maturation in hypertension.


Subject(s)
Blood Platelets/metabolism , Hypertension/blood , Plasma Membrane Calcium-Transporting ATPases/metabolism , Adult , Case-Control Studies , Gene Expression Profiling , Humans , Middle Aged , Sarcoplasmic Reticulum Calcium-Transporting ATPases/metabolism , Thrombopoiesis/physiology
19.
Platelets ; 17(6): 421-33, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16973504

ABSTRACT

The aetiology of adolescent idiopathic scoliosis (AIS), the most common form of scoliosis, is unclear. Previous studies showed controversial platelet abnormalities including intracellular calcium. Platelet Ca2+ homeostasis is controlled by a multi-Ca2+-ATPase system including SERCA (sarco/endoplasmic reticulum Ca2+-ATPase) and PMCA (plasma membrane Ca2+-ATPase) isoforms. Here, we first investigated the expression of PMCA4b, SERCA3a and SERCA2b isoforms in platelets of 17 patients with AIS. Patients presenting thoracic curves were found to present a higher PMCA4b expression coupled to a lower SERCA3a one in agreement with an abnormality in platelet maturation. Indeed, using PMA-treated MEG 01 cells, an in vitro model of megakaryocytopoiesis, we found an increase in SERCA3a expression, associated to a caspase-3 mediated C terminal proteolysis of PMCA4b. To look whether platelets reflect a basic defect in cell differentiation, we next identified osteoblast Ca2+-ATPases and studied their expressions in AIS. Major expressions of PMCA4b and SERCA2b were found in normal osteoblasts. Comparing platelets and osteoblasts in two additional patients with AIS, we found opposite and concerted regulations of the expressions of PMCA4b and caspase-3 substrate, PARP in both cell types. A systemic defect in cell differentiation involving caspase-3 can be proposed as a novel mechanism in the etiopathogenesis of the most frequent type of AIS. *R. Bredoux and E. Corvazier contributed equally to this work.


Subject(s)
Blood Platelets/enzymology , Cell Differentiation/physiology , Osteoblasts/enzymology , Plasma Membrane Calcium-Transporting ATPases/metabolism , Sarcoplasmic Reticulum Calcium-Transporting ATPases/metabolism , Scoliosis/enzymology , Thrombopoiesis/physiology , Adolescent , Adult , Biomarkers/blood , Biomarkers/metabolism , Cell Membrane/genetics , Cell Membrane/metabolism , Child , Child, Preschool , Endoplasmic Reticulum/metabolism , Female , Gene Expression Profiling , Humans , Male , Osteoblasts/metabolism , Plasma Membrane Calcium-Transporting ATPases/genetics , Sarcoplasmic Reticulum Calcium-Transporting ATPases/genetics , Scoliosis/blood , Scoliosis/classification , Thrombopoiesis/genetics
20.
Biochem Biophys Res Commun ; 345(4): 1377-85, 2006 Jul 14.
Article in English | MEDLINE | ID: mdl-16725111

ABSTRACT

Sarco/endoplasmic reticulum Ca(2+)ATPases (SERCAs) pump free Ca(2+) from the cytosol into the endoplasmic reticulum. The human SERCA3 family counts six members named SERCA3a to 3f. However, the exact role of these different isoforms in cellular physiology remains undetermined. In this study, we compared some physiological consequences of SERCA3b and SERCA3f overexpression in HEK-293 cells. We observed that overexpression of SERCA3b affected cell adhesion capacity associated with a major disorganization of F-actin and a decrease in focal adhesion. Furthermore, we found that SERCA3f overexpression resulted in an increase in endoplasmic reticulum stress markers (including processing of X-box-binding protein-1 (XBP-1) mRNA and expression of chaperone glucose-regulated protein 78 (GRP78)). This was associated with the activation of caspase cascade and a higher spontaneous cell death. In conclusion, these data point for the first time to distinct physiological roles of SERCA3 isoforms in cell functions.


Subject(s)
Calcium-Transporting ATPases/metabolism , Caspases/metabolism , Isoenzymes/metabolism , Apoptosis/drug effects , Apoptosis/physiology , Blotting, Western , Calcium-Transporting ATPases/genetics , Calcium-Transporting ATPases/physiology , Caspase 3 , Caspase Inhibitors , Cell Adhesion/drug effects , Cell Adhesion/physiology , Cell Line , Cell Survival/drug effects , Cell Survival/physiology , Cysteine Proteinase Inhibitors/pharmacology , DNA-Binding Proteins/genetics , Endoplasmic Reticulum Chaperone BiP , Enzyme Activation/drug effects , Gene Expression , Humans , Isoenzymes/genetics , Isoenzymes/physiology , Nuclear Proteins/genetics , Oligopeptides/pharmacology , RNA, Messenger/genetics , RNA, Messenger/metabolism , Regulatory Factor X Transcription Factors , Reverse Transcriptase Polymerase Chain Reaction , Sarcoplasmic Reticulum/metabolism , Sarcoplasmic Reticulum/physiology , Sarcoplasmic Reticulum Calcium-Transporting ATPases , Time Factors , Transcription Factors , Transfection , X-Box Binding Protein 1
SELECTION OF CITATIONS
SEARCH DETAIL
...