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1.
Food Chem ; 332: 127405, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-32603919

ABSTRACT

The two-phase technology for olive oil extraction generates large amounts of patè olive cake (POC), a by-product that is rich in bioactive health-promoting compounds. Here, response surface methodology (RSM) was used to maximize supercritical-CO2 oil extraction from POC, while minimizing operative temperature, pressure and time. Under the optimal parameters (40.2 °C, 43.8 MPa and time 30 min), the oil yield was 14.5 g·100 g-1 dw (~65% of the total oil content of the freeze-dried POC matrix), as predicted by RSM. Compared with freeze-dried POC, the oil contained more phytosterols (13-fold), tocopherols (6-fold) and squalene (8-fold) and was a good source of pentacyclic triterpenes. When the biological effects of POC oil intake (20-40 µL·die-1) were evaluated in the livers of BALB/c mice, no significant influence on redox homeostasis was observed. Notably, a decline in liver triglycerides alongside increased activities of NAD(P)H:Quinone Oxidoreductase 1, Carnitine Palmitoyl-CoA Transferase and mitochondrial respiratory complexes suggested a potential beneficial effect on liver fatty acid oxidation.


Subject(s)
Chromatography, Supercritical Fluid/methods , Olive Oil/chemistry , Animals , Carbon Dioxide/chemistry , Lipid Peroxidation , Liver/drug effects , Liver/metabolism , Mice , Mice, Inbred BALB C , Olea/metabolism , Olive Oil/isolation & purification , Olive Oil/pharmacology , Phytosterols/chemistry , Phytosterols/isolation & purification , Surface Properties , Temperature , Tocopherols/chemistry , Tocopherols/isolation & purification , Triglycerides/metabolism
2.
J Environ Manage ; 265: 110574, 2020 Jul 01.
Article in English | MEDLINE | ID: mdl-32421563

ABSTRACT

The Olive Mill Wastewaters (OMWs) are one of the most important agro-industrial wastes of the Mediterranean Countries and the disposal by draining them onto land has been proved to be damaging for soils, plants and groundwater due to their polluting power. The present report describes a new method for bio-detoxification of undiluted fresh OMW based on the driven selection of aerobic yeasts and bacteria. The identified yeast Candida boidinii A5y and the bacterium Paenibacillus albidus R32b strains allowed the treatment of freshly produced raw OMW characterized by very high COD value and phenolic content, when applied as sequential inoculum. The treated OMW showed the absence of antimicrobial effects and a strongly reduction of phytotoxic activity on the germination of several plant seeds. The process was successfully validated on an industrial scale without any pre-treatment, dilution and/or supplementation of the raw waste. Bio-detoxified OMW produced by this sustainable and low-cost process would be suitable for new non-chemical fertigation or soilless applications. The described procedure represents a virtuous example of circular economy efficaciously applied for a depleting agri-food resource.


Subject(s)
Olea , Wastewater , Bacteria , Industrial Waste , Olive Oil , Plant Oils , Saccharomyces cerevisiae , Waste Disposal, Fluid
3.
Plants (Basel) ; 8(8)2019 Aug 05.
Article in English | MEDLINE | ID: mdl-31387331

ABSTRACT

The olive is a fruit tree species with a century-old history of cultivation in theMediterranean basin. In Apulia (Southern Italy), the olive is of main social, cultural and economicimportance, and represents a hallmark of the rural landscape. However, olive cultivation in thisregion is threatened by the recent spread of the olive quick decline syndrome (OQDS) disease, thusthere is an urgent need to explore biodiversity and search for genetic sources of resistance. Herein,a genetic variation in Apulian olive germplasm was explored, as a first step to identify genotypeswith enhanced bio-agronomic traits, including resistance to OQDS. A preselected set of nuclearmicrosatellite markers allowed the acquisition of genotypic profiles, and to define geneticrelationships between Apulian germplasm and widespread cultivars. The analysis highlighted thebroad genetic variation in Apulian accessions and the presence of different unique genetic profiles.The results of this study lay a foundation for the organization of new breeding programs for olivegenetic improvement.

4.
Food Chem ; 240: 1184-1192, 2018 Feb 01.
Article in English | MEDLINE | ID: mdl-28946241

ABSTRACT

This study investigates the effects of tomato puree fortification with several anthocyanin-rich food colorants on bioactive compound content (phenolics, isoprenoids), antioxidant capacity, in vitro biological activities and consumer acceptance. Tomato puree (tp) was added with different anthocyanin extracts from black carrot (Anthocarrot), grape fruit skins (Enocolor), elderberry fruits (Elderberry) or mahaleb cherry fruits (Mahaleb), thus obtaining a 'functional tomato puree' (ftp). The consumer acceptance (colour, flavor, taste, visual appearance) was at high level, except for Mahaleb-added ftp. Compared to the control (tp), the addition of colouring extracts increased significantly the total phenolic content, before pasteurization, in addition to the expected anthocyanin content. However, after pasteurization, mostly Anthocarrot-ftp preserved an increased phenolic (+53%) content, as well as a higher antioxidant capacity (50%), more than the other added-extracts. Consistently, against tp, Anthocarrot-ftp exhibited an increased anti-inflammatory capacity as showed by the reduced expression of vascular cell adhesion molecule (VCAM)-1 in human cultured endothelial cells, under inflammatory conditions.


Subject(s)
Solanum lycopersicum , Anthocyanins , Antioxidants , Food, Fortified , Fruit , Humans , Phenols
5.
Appl Biochem Biotechnol ; 172(6): 2916-31, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24458655

ABSTRACT

The ERY4 laccase gene from Pleurotus eryngii was expressed in Saccharomyces cerevisiae and the recombinant laccase resulted to be not biologically active. This gene was thus modified to obtain chimerical enzymes derived from the substitution of N-, C- and both N- and C-terminal regions with the corresponding regions of Ery3 laccase, another laccase isoform of P. eryngii. The chimerical isoform named 4NC3, derived from the substitution of both N- and C-terminal regions, showed the best performances in terms of enzymatic activities, affinities for different substrates and stability at a broad range of temperatures and pHs. The chimerical 4NC3 laccase isoform was displayed on the cell surface of S. cerevisiae using the N-terminal fusion with either the Pir2 or the Flo1 S. cerevisiae proteins as anchor attachment sequence. Immunofluorescence microscopy and Western blot analyses confirmed the localization of 4NC3 on the yeast cell surface. The enzyme activity on specific laccase substrates revealed that 4NC3 laccase was immobilized in active form on the cell surface. To our knowledge, this is the first example of expression of a chimerical fungal laccase by yeast cell display.


Subject(s)
Fungal Proteins/genetics , Gene Expression Regulation, Fungal , Laccase/genetics , Pleurotus/genetics , Recombinant Fusion Proteins/genetics , Saccharomyces cerevisiae/genetics , Cell Surface Display Techniques , Fungal Proteins/metabolism , Glycoproteins/genetics , Glycoproteins/metabolism , Heat-Shock Proteins/genetics , Heat-Shock Proteins/metabolism , Hydrogen-Ion Concentration , Kinetics , Laccase/metabolism , Mannose-Binding Lectins/genetics , Mannose-Binding Lectins/metabolism , Pleurotus/metabolism , Protein Structure, Tertiary , Recombinant Fusion Proteins/metabolism , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/metabolism , Temperature
6.
Bioresour Technol ; 102(2): 982-9, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20934327

ABSTRACT

The yeast population dynamics in olive wastewaters (OMW), sampled in five mills from Salento (Apulia, Southern Italy), were investigated. Three hundred yeasts were isolated in five industrial mills and identified by molecular analysis. Strains belonging to Geotrichum, Saccharomyces, Pichia, Rhodotorula and Candida were detected. Five G. candidum strains were able to grow in OMW as the sole carbon source and to reduce phenolics, chemical oxygen demand (COD) and antimicrobial compounds. One G. candidum isolate was selected for whole-cell immobilization in calcium alginate gel. The COD and phenolic reduction obtained with immobilized cells showed a 2.2- and 2-fold increase compared to the removal obtained with free cells, respectively. The immobilization system enhanced yeast oxidative activity by avoiding the presence of microbial protease in treated OMW. To our knowledge, this is the first report on G. candidum whole-cell immobilization for OMW bioremediation.


Subject(s)
Industrial Waste/analysis , Plant Oils/chemistry , Waste Disposal, Fluid , Water Purification/methods , Yeasts/cytology , Yeasts/metabolism , Anti-Bacterial Agents/pharmacology , Bacillus megaterium/drug effects , Biodegradation, Environmental/drug effects , Biological Oxygen Demand Analysis , Biomass , Cells, Immobilized/cytology , Cells, Immobilized/metabolism , Extracellular Space/drug effects , Extracellular Space/enzymology , Molecular Sequence Data , Olive Oil , Oxidation-Reduction/drug effects , Phenols/isolation & purification , Time Factors , Yeasts/drug effects , Yeasts/isolation & purification
7.
Plant Biol (Stuttg) ; 13(1): 51-8, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21143725

ABSTRACT

Artemisia annua L. is a herb traditionally used for treatment of fevers. The glandular trichomes of this plant accumulate, although at low levels, artemisinin, which is highly effective against malaria. Due to the great importance of this compound, many efforts have been made to improve knowledge on artemisinin production both in plants and in cell cultures. In this study, A. annua suspension cultures were established in order to investigate the effects of methyl jasmonate (MeJA) and miconazole on artemisinin biosynthesis. Twenty-two micro molar MeJA induced a three-fold increase of artemisinin production in around 30 min; while 200 µm miconazole induced a 2.5-fold increase of artemisinin production after 24 h, but had severe effects on cell viability. The influence of these treatments on expression of biosynthetic genes was also investigated. MeJA induced up-regulation of CYP71AV1, while miconazole induced up-regulation of CPR and DBR2.


Subject(s)
Acetates/pharmacology , Artemisia annua/drug effects , Artemisia annua/metabolism , Artemisinins/metabolism , Cyclopentanes/pharmacology , Gene Expression Regulation, Plant/drug effects , Miconazole/pharmacology , Oxylipins/pharmacology , Artemisia annua/cytology , Artemisia annua/genetics , Artemisinins/chemistry , Cell Survival/drug effects , Cells, Cultured , Molecular Structure , RNA, Messenger/biosynthesis
8.
Plant Biol (Stuttg) ; 12(1): 13-22, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20653884

ABSTRACT

Plants respond to environmental stimuli, such as heat shock, by re-programming cellular activity through differential gene expression, mainly controlled at the transcription level. The current study refers to two sunflower small heat shock protein (sHSP) genes arranged in tandem in head-to-head orientation and linked by a 3809 bp region. These genes exhibit only slight structural differences in the coding portion. They code for cytosolic class I sHSPs and are named HaHSP17.6a and HaHSP17.6b according to the molecular weight of the putative proteins. The genomic organization of these genes is consistent with the idea that many HSP genes originate from duplication events; in this case, probably an inversion and duplication occurred. The HaHSP17.6a and HaHSP17.6b genes are characterized by different expression levels under various heat stress conditions; moreover, their expression is differently induced by various elicitors. The differential regulation observed for HaHSP17.6a and HaHSP17.6b genes differs from previous observations on duplicated sHSP genes in plants.


Subject(s)
Heat-Shock Proteins/metabolism , Helianthus/genetics , Hot Temperature , Plant Proteins/metabolism , Base Sequence , Cloning, Molecular , DNA, Plant/genetics , Gene Expression Regulation, Plant , Genomic Library , Heat-Shock Proteins/genetics , Helianthus/metabolism , Molecular Sequence Data , Plant Proteins/genetics , Sequence Analysis, DNA
9.
Food Addit Contam ; 22(4): 309-15, 2005 Apr.
Article in English | MEDLINE | ID: mdl-16019800

ABSTRACT

Fusarium trichothecenes are a group of fungal toxic metabolites whose synthesis requires the action of gene products from three different genetic loci. We evaluated, both chemically and by PCR assays, 55 isolates of Fusarium culmorum from eight European countries and different host plants for their ability to produce trichothecenes. Specific sequences in the Tri6-Tri5 intergenic region were associated with deoxynivalenol production. Sequences in the Tri3 gene were also associated with deoxynivalenol production and specific primer sets were selected from these sequences to identify 3-acetyl-deoxynivalenol or 15-acetyl-deoxynivalenol chemotypes. Specific sequences in the Tri5 and Tri7 genes were associated with the nivalenol chemotype but not with the deoxynivalenol chemotype. Two chemotypes were identified by chemical analysis and confirmed by PCR. Strains of the nivalenol chemotype produced nivalenol (up to 260 microg g(-1)) and 4-acetyl-nivalenol (up to 60 microg g(-1)), strains with the 3-acetyl-deoxynivalenol chemotype produced deoxynivalenol (up to 1700 microg g(-1)) and 3-acetyl-deoxynivalenol (up to 600 microg g(-1)). Three strains of F. culmorum from France, previously reported as 15-acetyl-deoxynivalenol producers, had the 3-acetyl-deoxynivalenol chemotype. The results are consistent with data from other European countries on the occurrence of the nivalenol and 3-acetyl-deoxynivalenol chemotypes and provide support for the hypothesis that European isolates of F. culmorum producing deoxynivalenol belong only to the 3-acetyl-deoxynivalenol chemotype. The production of trichothecenes from F. culmorum isolates from walnut (3-acetyl-deoxynivalenol chemotype) and leek (nivalenol chemotype) is reported for the first time.


Subject(s)
Food Microbiology , Fusarium/classification , Trichothecenes/biosynthesis , DNA, Fungal/genetics , Europe , Fusarium/genetics , Fusarium/metabolism , Genes, Fungal , Mycological Typing Techniques/methods , Mycoses/microbiology , Plant Diseases/microbiology , Polymerase Chain Reaction/methods , Triticum/microbiology
10.
Food Addit Contam ; 22(4): 389-95, 2005 Apr.
Article in English | MEDLINE | ID: mdl-16019809

ABSTRACT

In recent years, public pressure to reduce the use of synthetic fungicides in agriculture has increased. Concerns have been raised about both the environmental impact and the potential health risk related to the use of these compounds. Therefore, considerable efforts have been made towards the development of alternative crop protectants. The European Commission has been actively encouraging the development and commercial implementation of new compounds known as 'green chemicals'. In this context, an increase in the knowledge of plant defence responses to toxigenic fungi, which is covered in this review, will help to discover new plant products with antifungal activity and to design new strategies to improve plant resistance to these pathogens.


Subject(s)
Antifungal Agents/pharmacology , Crops, Agricultural/microbiology , Mycoses/prevention & control , Plant Diseases/microbiology , Food Contamination/prevention & control , Fungi/drug effects , Plant Proteins/pharmacology
11.
Biosens Bioelectron ; 20(6): 1140-8, 2004 Dec 15.
Article in English | MEDLINE | ID: mdl-15556360

ABSTRACT

Surface plasmon resonance (SPR) has recently gained attention as a label-free method for the detection of biological molecules binding onto functionalised surfaces. It is one of the most sensitive detection method for monitor variations in the thickness and refractive index in ultra-thin films. Here, the adsorption processes of oligonucleotides onto gold substrates have been investigated in aqueous buffer solution using SPR imaging measurements. The hybridization of a thiol-modified, single stranded oligonucleotide anchored to a gold surface via thiol group, with its complementary sequence has been observed and characterised monitoring the hybridization process by SPR equipment. In situ investigation of smallest changes in SPR imaging measurements dynamically performed in liquid phase in the presence of DNA complementary probes was performed. Infrared spectroscopy and scanning electron microscopy characterisation of the functionalised gold surfaces of the biosensor were compared with the images obtained by SPR experimental apparatus.


Subject(s)
Biosensing Techniques/methods , DNA Probes/chemistry , DNA/analysis , DNA/chemistry , In Situ Hybridization/methods , Oligonucleotide Array Sequence Analysis/methods , Surface Plasmon Resonance/methods , Biosensing Techniques/instrumentation , Coated Materials, Biocompatible/chemistry , DNA/ultrastructure , DNA Probes/ultrastructure , In Situ Hybridization/instrumentation , Oligonucleotide Array Sequence Analysis/instrumentation , Solutions , Surface Properties
12.
Eur J Biochem ; 268(5): 1500-7, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11231304

ABSTRACT

We have characterized an almond (Prunus dulcis) lipoxygenase (LOX) that is expressed early in seed development. The presence of an active lipoxygenase was confirmed by western blot analysis and by measuring the enzymatic activity in microsomal and soluble protein samples purified from almond seeds at this stage of development. The almond lipoxygenase, which had a pH optimum around 6, was identified as a 9-LOX on the basis of the isomers of linoleic acid hydroperoxides produced in the enzymatic reaction. A genomic clone containing a complete lipoxygenase gene was isolated from an almond DNA library. The 6776-bp sequence reported includes an open reading frame of 4667 bp encoding a putative polypeptide of 862 amino acids with a calculated molecular mass of 98.0 kDa and a predicted pI of 5.61. Almond seed lipoxygenase shows 71% identity with an Arabidopsis LOX1 gene and is closely related to tomato fruit and potato tuber lipoxygenases. The sequence of the active site was consistent with the isolated gene encoding a 9-LOX.


Subject(s)
Gene Expression Regulation, Plant , Lipoxygenase/genetics , Lipoxygenase/metabolism , Rosales/enzymology , Seeds/enzymology , Amino Acid Sequence , Arabidopsis/enzymology , Base Sequence , Chromatography, High Pressure Liquid , Cloning, Molecular , DNA Probes/genetics , DNA Probes/metabolism , Exons , Fatty Acids, Unsaturated/metabolism , Gene Expression Regulation, Developmental , Gene Expression Regulation, Enzymologic , Hydrogen-Ion Concentration , Introns , Linoleic Acids/metabolism , Lipid Peroxides/metabolism , Lipoxygenase/chemistry , Microsomes/enzymology , Molecular Sequence Data , Molecular Weight , Phylogeny , Rosales/genetics , Rosales/growth & development , Seeds/genetics , Seeds/growth & development , Solubility
13.
Article in English | MEDLINE | ID: mdl-15954598

ABSTRACT

We identified a lipoxygenase expressed early during almond seed development. Biochemical and molecular characterisation showed that the enzyme produces almost exclusively 9-hydroperoxides which have been demonstrated to be important factors for the production of characteristic aromas in several fruits. An almond LOX cDNA was identified by RT-PCR using RNA extracted from immature almond seeds. Sequence analysis revealed that the identified gene is closely related to tomato fruit and potato tuber lipoxygenases. The isolated cDNA was cloned into pET24a and the expression of recombinant protein was induced in E. coli. The presence of an active LOX was confirmed in cells containing the recombinant vector. HPLC analysis of the reaction products of recombinant almond LOX confirmed that the isolated cDNA encodes a 9-LOX.


Subject(s)
Lipoxygenase/metabolism , Catalysis , Chromatography, High Pressure Liquid , Corylus/enzymology , Food Industry , Kinetics , Lipoxygenase/genetics , Prunus/enzymology , Prunus/genetics , RNA/genetics , RNA/isolation & purification , Recombinant Proteins/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Seeds/enzymology , Taste
14.
Plant Cell Rep ; 16(11): 792-796, 1997 Sep.
Article in English | MEDLINE | ID: mdl-30727691

ABSTRACT

Sunflower suspension cell cultures were subjected to different heat treatments and the electrophoretic patterns of heat-induced endocellular and secreted proteins were analyzed. In response to heat shock (3 h at 40°C), sunflower cells synthesized new polypeptides and secreted them into the medium, while the synthesis of other polypeptides was suppressed. Two major polypeptides of about 50 and 32 kDa were strongly induced. The two-dimensional electrophoretic analysis showed that the 32-kDa band is composed of at least four different polypeptides. Western blotting hybridizations of secreted proteins with various lectins were performed. The 32-kDa band gave a positive signal with concanavalin A.

15.
Rev. Inst. Méd. Sucre ; 41(105): 89-91, feb. 1995. ilus
Article in Spanish | LILACS | ID: lil-174623

ABSTRACT

Se presenta un caso de higado poliquistico en una paciente en la sexta decada de la vida, cuya presentacion clinica y examnenes complementarios, como ecografia y laboratorio, demuestran la presencia de una colecistitis cronica con litiasis multiple y la poliquistosis hepatica. Se realiza el tratamiento de colecistectomia y quistectomia anterior con drenaje de contenido quistico liquido. El estudio histopatologico reporta colecistitis cronica reagudizada. No se encuentra amebas ni escolex. Paciente en buenas condicones y con examenes de laboratorio normales, despues de la operacion.


Subject(s)
Humans , Female , Aged , Liver/pathology , Choledochal Cyst/surgery , Bolivia , Cholecystectomy/rehabilitation , Clinical Diagnosis , Drainage/statistics & numerical data , Pain/physiopathology , Surgical Procedures, Operative , Ultrasonography
16.
J Neurochem ; 63(5): 1900-7, 1994 Nov.
Article in English | MEDLINE | ID: mdl-7523602

ABSTRACT

LAN-1 is a human neuroblastoma cell line that, in the undifferentiated state, does not respond to membrane depolarization with an elevation of [Ca2+]i, monitored by fura-2 single-cell microfluorimetry. The exposure of LAN-1 cells to the differentiating agent retinoic acid induced the appearance of [Ca2+]i elevation elicited by 55 mM K+. Maitotoxin, a putative activator of voltage-sensitive Ca2+ channels, did not evoke an elevation of [Ca2+]i in undifferentiated LAN-1 cells, but produced a marked and sustained increase in [Ca2+]i when superfused in retinoic acid-treated cells. Both high K(+)- and maitotoxin-induced [Ca2+]i elevation in retinoic acid-differentiated LAN-1 cells was reversed by the lanthanide Gd3+, an inorganic Ca(2+)-entry blocker, and by the snail toxin omega-conotoxin GVIA, which interacts with the N subtype of voltage-sensitive Ca2+ channels. In contrast, both Bay K 8644 and nimodipine, dihydropyridines that selectively activate or block, respectively, the L-channel subtype, were completely ineffective. The tumor promoter phorbol 12-myristate 13-acetate (100 nM), a protein kinase C activator, inhibited the elevation of [Ca2+]i due to Ca2+ influx elicited by membrane depolarization. K(+)-induced [Ca2+]i elevation appeared 24 h after the addition of retinoic acid and reached the highest magnitude after 72 h. Furthermore, 8 days after the removal of the differentiating agent from the culture medium, the high K(+)-induced increase of [Ca2+]i was still present.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Calcium/metabolism , Marine Toxins/pharmacology , Membrane Potentials/physiology , Neuroblastoma/metabolism , Neuroblastoma/pathology , Oxocins , Tretinoin/pharmacology , 3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester/pharmacology , Calcium/analysis , Cell Differentiation/drug effects , Cytophotometry , Humans , Membrane Potentials/drug effects , Neuroblastoma/chemistry , Nimodipine/pharmacology , Peptides/pharmacology , Potassium/pharmacology , Tetradecanoylphorbol Acetate/pharmacology , Time Factors , Tumor Cells, Cultured , omega-Conotoxin GVIA
17.
Plant Cell Rep ; 13(7): 406-10, 1994 Apr.
Article in English | MEDLINE | ID: mdl-24193912

ABSTRACT

An in vitro culture of Alkanna tinctoria Tausch cells was set up in order to investigate the possibility of producing alkannin, a red naphthoquinone naturally present in the root bark of this plant. Furthermore, an in vitro culture of callusderived roots was established and the production of alkannin evaluated. In the different experimental conditions investigated, differences in the production of alkannin derivatives as well as in the type of pigments produced, were observed. The potential use of this technology is discussed.

18.
J Neurochem ; 59(1): 1-9, 1992 Jul.
Article in English | MEDLINE | ID: mdl-1319463

ABSTRACT

The LAN-1 clone, a cell line derived from a human neuroblastoma, possesses muscarinic receptors. The stimulation of these receptors with increasing concentrations of carbachol (CCh; 1-1,000 microM) caused a dose-dependent increase of the intracellular free Ca2+ concentration ([Ca2+]i). This increase was characterized by an early peak phase (10 s) and a late plateau phase. The removal of extracellular Ca2+ reduced the magnitude of the peak phase to approximately 70% but completely abolished the plateau phase. The muscarinic-activated Ca2+ channel was gadolinium (Gd3+) blockade and nimodipine and omega-conotoxin insensitive. In addition, membrane depolarization did not cause any increase in [Ca2+]i. The CCh-induced [Ca2+]i elevation was concentration-dependently inhibited by pirenzepine and 4-diphenylacetoxy-N-methylpiperidine methiodide, two rather selective antagonists of M1 and M3 muscarinic receptor subtypes, respectively, whereas methoctramine, an M2 antagonist, was ineffective. The coupling of M1 and M3 receptor activation with [Ca2+]i elevation does not seem to be mediated by a pertussis toxin-sensitive guanine nucleotide-binding protein or by the diacylglycerol-protein kinase C system. The mobilization of [Ca2+]i elicited by M1 and M3 muscarinic receptor stimulation seems to be dependent on an inositol trisphosphate-sensitive intracellular store. In addition, ryanodine did not prevent CCh-induced [Ca2+]i mobilization, and, finally, LAN-1 cells appear to lack caffeine-sensitive Ca2+ stores, because the methylxanthine was unable to elicit intracellular Ca2+ mobilization, under basal conditions, after a subthreshold concentration of CCh (0.3 microM), or after thapsigargin.


Subject(s)
Calcium/metabolism , Neuroblastoma/metabolism , Receptors, Muscarinic/metabolism , Calcium Channel Blockers/pharmacology , Calcium Channels/metabolism , Calcium Channels/physiology , Carbachol/pharmacology , Electrophysiology , Humans , Inositol 1,4,5-Trisphosphate/pharmacology , Intracellular Membranes/metabolism , Muscarinic Antagonists , Neuroblastoma/pathology , Osmolar Concentration , Pertussis Toxin , Protein Kinase C/metabolism , Tumor Cells, Cultured , Virulence Factors, Bordetella/pharmacology
19.
Funct Neurol ; 7(3): 239-42, 1992.
Article in English | MEDLINE | ID: mdl-1323509

ABSTRACT

Endothelin-1 (ET-1) produced a dose-dependent increase of intracellular Ca++ concentrations [Ca++]i characterized by an early peak phase and a delayed plateau in LAN-1 human neuroblastoma cells. The ET-1 receptor showed a rapid desensitization since a second pulse application of ET-1 did not elicit a further [Ca++]i increase. Furthermore thapsigargin, an endoplasmic reticulum Ca(++)-ATPase inhibitor, completely abolished the ET-1 induced intracellular Ca++ elevation.


Subject(s)
Calcium/metabolism , Endothelins/pharmacology , Intracellular Fluid/drug effects , Receptors, Cell Surface/drug effects , Tumor Cells, Cultured/drug effects , Cell Line , Dose-Response Relationship, Drug , Humans , Intracellular Fluid/physiology , Microscopy, Fluorescence , Neuroblastoma , Receptors, Cell Surface/physiology , Receptors, Endothelin
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