280 research outputs found
C2C12 MYOBLASTS RELEASE MICRO-VESICLES CONTAINING mtDNA AND PROTEINS INVOLVED IN SIGNAL TRANSDUCTION
none11Micro-vesicles can be released by different cell types and operate as ‘safe containers’ mediatine inter-cellular communication. In this work we investigated whether cultured myoblasts could release exosomes. The reported data demonstrate, for the first time, that C2C12 myoblasts release micro-vesicles as shown by the presence of two exosome markers (Tsg101 and Alix proteins). Using real-time PCR analysis it was shown that these micro-vesicles, like other cell types, carry mtDNA. Proteomic characterization of the released micro-vesicle contents showed the presence of many proteins involved in signal transduction. The bioinformatics assessment of the Disorder Index and Aggregation Index of these proteins suggested that C2C12 micro-vesicles mainly deliver the machinery for signal transduction to target cells rather than key proteins involved in hub functions in molecular networks. The presence of IGFBP-5 in the purified micro-vesicles represents an exception, since this binding protein can play a key role in the modulation of the IGF-1 signalling pathway.
In conclusion, the present findings demonstrate that skeletal muscle cells release micro-vesicles, which probably have an important role in the communication processes within skeletal muscles and between skeletal muscles and other organs. In particular, the present findings suggest possibile new diagnostic approaches to skeletal muscle diseases.openM. GUESCINI; D. GUIDOLIN; L. VALLORANI; L. CASADEI; A.M. GIOACCHINI; P. TIBOLLO; M. BATTISTELLI; E. FALCIERI; L. BATTISTIN; L.F. AGNATI; V. STOCCHIGuescini, Michele; D., Guidolin; Vallorani, Luciana; Casadei, Lucia; Gioacchini, ANNA MARIA; P., Tibollo; Battistelli, Michela; Falcieri, Elisabetta; L., Battistin; L. F., Agnati; Stocchi, Vilbert
Microvesicle and tunneling nanotube mediated intercellular transfer of g-protein coupled receptors in cell cultures.
none12Recent evidence shows that cells exchange collections of signals via microvesicles (MVs) and tunneling nano-tubes (TNTs). In this paper we have investigated whether in cell cultures GPCRs can be transferred by means of MVs and TNTs from a source cell to target cells. Western blot, transmission electron microscopy and gene expression analyses demonstrate that A(2A) and D(2) receptors are present in released MVs. In order to further demonstrate the involvement of MVs in cell-to-cell communication we created two populations of cells (HEK293T and COS-7) transiently transfected with D(2)R-CFP or A(2A)R-YFP. These two types of cells were co-cultured, and FRET analysis demonstrated simultaneously positive cells to the D(2)R-CFP and A(2A)R-YFP. Fluorescence microscopy analysis also showed that GPCRs can move from one cell to another also by means of TNTs. Finally, recipient cells pre-incubated for 24 h with A(2A)R positive MVs were treated with the adenosine A(2A) receptor agonist CGS-21680. The significant increase in cAMP accumulation clearly demonstrated that A(2A)Rs were functionally competent in target cells. These findings demonstrate that A(2A) receptors capable of recognizing and decoding extracellular signals can be safely transferred via MVs from source to target cells.openM. Guescini; G. Leo; S. Genedani; C. Carone; F. Pederzoli; F. Ciruela; D. Guidolin; V. Stocchi; M. Mantuano; D.O. Borroto-Escuela; K. Fuxe; L.F. AgnatiGuescini, Michele; G., Leo; S., Genedani; C., Carone; F., Pederzoli; F., Ciruela; D., Guidolin; Stocchi, Vilberto; Mantuano, Michela; D. O., Borroto Escuela; K., Fuxe; L. F., Agnat
Endothelin-1 (ET-1) modulates epithelial-mesenchymal transition (EMT), which contributes to kidney tubulo-interstitial fibrosis in angiotensin II-dependent hypertension
The origin of myofibroblasts remains uncertain, but studies suggest that the epithelial cells may acquire a fibroblast-like phenotype via epithelial-mesenchymal transition (EMT). Objective of the study was to investigate whether EMT may contribute to the development of kidney fibrosis in a model of angiotensin II-dependent hypertension and to identify the role of ET-1 via ETA/ETB receptors. Transgenic rats TGRen2 (n=35) received for 4 weeks one of the following treatments a) irbesartan, b) bosentan, non selective ETA /ETB receptor antagonist, c) BMS-182874, selective ETA,antagonist, d) BMS+irbesartan, e) placebo. EMT was assessed by investigating coexpression of a marker of epithelial cell (E-cadherin) and one of myofibroblast (S100A4 or alfa-SMA) with double immunofluorescence. Specific immunoreactivity was measured using QWinStandard Leica ImageTMsoftware. A reduction in blood pressure was found only with irbesartan, whereas both bosentan and irbesartan significantly lowered tubulo-interstitial fibrosis. Coexpression of E-cadherin and S100A4, or E-cadherin and alfa-SMA, markedly decreased in the tubular cells of TGRen2 treated with irbesartan or bosentan. Alfa-SMA expression decreased after irbesartan, bosentan and BMS+irbesartan, but not after BMS. S100A4 expression was reduced after irbesartan, bosentan and BMS+irbesartan. E-cadherin increased only after irbesartan. Coexpression of the markers of myofibroblasts and kidney epithelial cells, by demonstrating the development of EMT during the onset of kidney hypertension-induced damage, suggests a crucial role of EMT in the pathogenesis of Ang II-mediated fibrosis. The reduction of myofibroblast markers not only after irbesartan, but also after blockade of ETA/ETB receptors, suggests an involvement of ET-1 in the development of Ang II-mediated EMT
Endothelin-1 (ET-1) modulates epithelial-mesenchymal transition (EMT), which contributes to kidney tubulo-interstitial fibrosis in angiotensin II-dependent hypertension
The origin of myofibroblasts remains uncertain, but studies suggest that the epithelial cells may acquire a fibroblast-like phenotype via epithelial-mesenchymal transition (EMT). Objective of the study was to investigate whether EMT may contribute to the development of kidney fibrosis in a model of angiotensin II-dependent hypertension and to identify the role of ET-1 via ETA/ETB receptors. Transgenic rats TGRen2 (n=35) received for 4 weeks one of the following treatments a) irbesartan, b) bosentan, non selective ETA /ETB receptor antagonist, c) BMS-182874, selective ETA,antagonist, d) BMS+irbesartan, e) placebo. EMT was assessed by investigating coexpression of a marker of epithelial cell (E-cadherin) and one of myofibroblast (S100A4 or alfa-SMA) with double immunofluorescence. Specific immunoreactivity was measured using QWinStandard Leica ImageTMsoftware. A reduction in blood pressure was found only with irbesartan, whereas both bosentan and irbesartan significantly lowered tubulo-interstitial fibrosis. Coexpression of E-cadherin and S100A4, or E-cadherin and alfa-SMA, markedly decreased in the tubular cells of TGRen2 treated with irbesartan or bosentan. Alfa-SMA expression decreased after irbesartan, bosentan and BMS+irbesartan, but not after BMS. S100A4 expression was reduced after irbesartan, bosentan and BMS+irbesartan. E-cadherin increased only after irbesartan. Coexpression of the markers of myofibroblasts and kidney epithelial cells, by demonstrating the development of EMT during the onset of kidney hypertension-induced damage, suggests a crucial role of EMT in the pathogenesis of Ang II-mediated fibrosis. The reduction of myofibroblast markers not only after irbesartan, but also after blockade of ETA/ETB receptors, suggests an involvement of ET-1 in the development of Ang II-mediated EMT
Caracterização da autoincompatibilidade em populações segregantes de macieira via marcadores de DNA para alelos S.
Abstract - The objective of this study was to characterize the parents and respective populations of apple trees regarding S-alleles to confirm their genealogy and to evaluate the efficiency of the molecular markers used. Sixteen specific sets of primers were used for identification of apple S-alleles by PCR. Two segregating populations of the Epagri Apple Breeding Program resulting from crosses between ?Fred Hough? × ?Monalisa? and ?M-11/00? × ?M-13/91? were evaluated. The expected segregations are 1:1:1:1 for full compatibility and 1:1 for semi-compatibility, which can be confirmed by the X2 test. The ?Fred Hough? (S5 S19) × ?Monalisa? (S2 S10) cross proved to be fully compatible; and two triploids were identified among the hybrids as well. The ?M-11/00? (S3 S19) × ?M-13/91? (S3 S5 ) cross was characterized as semi-compatible based on DNA markers, and the segregation of the S-alleles in the hybrids was 1:1, as expected. The segregation of the DNA markers occurred together with their respective S-alleles: S2, S3 , S5 , S10, and S19. Thus, characterization of the S-alleles not only allowed identification of compatibility between parents but also identified contaminations in segregating populations. Index terms: Malus × domestica Borkh., S genotype, S-RNase, allele-specific PCR, segregation. Caracterização da autoincompatibilidade em populações segregantes de macieira via marcadores de DNA para alelos S Resumo - O objetivo deste trabalho foi caracterizar genitores e respectivas populações de macieiras quanto aos alelos S para confirmar sua genealogia e para avaliar a eficiência dos marcadores moleculares utilizados. Conjuntos específicos de iniciadores foram utilizados para a identificação dos alelos S via PCR. Foram avaliadas duas populações segregantes do Programa de Melhoramento Genético de Macieira da Epagri resultantes dos cruzamentos entre ?Fred Hough? × ?Monalisa? e ?M-11/00? × ?M-13/91?. As segregações esperadas são 1:1:1:1 para compatibilidade total e 1:1 para semi compatibilidade, que podem ser confirmadas pelo teste X2 . O cruzamento ?Fred Hough? (S5 S19) × ?Monalisa? (S2 S10) foi identificado como totalmente compatível, e foram identificados dois triploides entre os híbridos. O cruzamento entre ?M-11/00? (S3 S19) × ?M-13/91? (S3 S5 ) mostrou-se semicompatível baseado nos marcadores moleculares, e a segregação dos alelos S nos híbridos foi de 1:1, como esperado. A segregação dos marcadores de DNA para S2 , S3, S5, S10 e S19 ocorreujuntamente com seus respectivos alelos S. Dessa forma, a caracterização dos alelos S, além de permitir identificar a compatibilidade entre os genitores, serviu para identificar contaminações em populações segregantes. Termos para indexação: Malus × domestica Borkh., genótipo S, S-RNase, PCR alelo-específico, segregação. 1 Industrial biotechnologist, M.Sc. Doctora
Biocontrol traits of Bacillus licheniformis GL174, a culturable endophyte of Vitis vinifera cv. Glera
Background
Bacillus licheniformis GL174 is a culturable endophytic strain isolated from Vitis vinifera cultivar Glera, the grapevine mainly cultivated for the Prosecco wine production. This strain was previously demonstrated to possess some specific plant growth promoting traits but its endophytic attitude and its role in biocontrol was only partially explored. In this study, the potential biocontrol action of the strain was investigated in vitro and in vivo and, by genome sequence analyses, putative functions involved in biocontrol and plant-bacteria interaction were assessed.
Results
Firstly, to confirm the endophytic behavior of the strain, its ability to colonize grapevine tissues was demonstrated and its biocontrol properties were analyzed. Antagonism test results showed that the strain could reduce and inhibit the mycelium growth of diverse plant pathogens in vitro and in vivo. The strain was demonstrated to produce different molecules of the lipopeptide class; moreover, its genome was sequenced, and analysis of the sequences revealed the presence of many protein-coding genes involved in the biocontrol process, such as transporters, plant-cell lytic enzymes, siderophores and other secondary metabolites.
Conclusions
This step-by-step analysis shows that Bacillus licheniformis GL174 may be a good biocontrol agent candidate, and describes some distinguished traits and possible key elements involved in this process. The use of this strain could potentially help grapevine plants to cope with pathogen attacks and reduce the amount of chemicals used in the vineyard
Effects of Hylan G-F 20 supplementation on cartilage preservation detected by magnetic resonance imaging in osteoarthritis of the knee: a two-year single-blind clinical trial
<p>Abstract</p> <p>Background</p> <p>Although viscosupplementation is an effective symptomatic treatment for knee osteoarthritis (OA), the effect of longer term administration on articular cartilage has not been fully explored. We examined the effect of viscosupplementation with Hylan G-F 20 on knee cartilage over 2 years in patients with knee OA.</p> <p>Methods</p> <p>In this prospective, single-blind, parallel control group pilot study, 78 patients with symptomatic knee OA (Kellgren-Lawrence grade II and III) were assigned to either intervention group (n = 39 receiving 4 courses of 3 × 2.0 ml of intra-articular Hylan G-F 20 injections at 6 month intervals) or control group (n = 39 receiving usual care for knee OA without injections). Magnetic resonance imaging of the study knee was performed at baseline, 12 and 24 months. Cartilage volume and defects were assessed using validated methods.</p> <p>Results</p> <p>Fifty-five subjects (71%) completed 24 month follow up. Over 24 months, the intervention group had a reduced annual percentage rate of medial and lateral tibial cartilage volume loss (mean ± SD, -0.3 ± 2.7% and -1.4 ± 4.3%) compared with the control group (2.3 ± 2.6% and 1.4 ± 2.6%, P = 0.001 and 0.005 for difference, respectively). The intervention group also showed reduced cartilage defect score increment in the medial tibiofemoral compartment (0.1 ± 1.3) compared with the control group (0.8 ± 1.5, P = 0.05).</p> <p>Conclusions</p> <p>Six monthly intra-articular injections of Hylan G-F 20 administered to patients with symptomatic knee OA have a beneficial effect on knee cartilage preservation measured by both cartilage volume and cartilage defects. Hylan G-F 20 warrants further evaluation in larger clinical trials as a possible disease-modifying agent in the treatment of knee OA.</p> <p>Trial Registration</p> <p>The study was registered with ClinicalTrials.gov (<a href="http://www.clinicaltrials.gov/ct2/show/NCT00393393">NCT00393393</a>).</p
Early Embryonic Vascular Patterning by Matrix-Mediated Paracrine Signalling: A Mathematical Model Study
During embryonic vasculogenesis, endothelial precursor cells of mesodermal origin known as angioblasts assemble into a characteristic network pattern. Although a considerable amount of markers and signals involved in this process have been identified, the mechanisms underlying the coalescence of angioblasts into this reticular pattern remain unclear. Various recent studies hypothesize that autocrine regulation of the chemoattractant vascular endothelial growth factor (VEGF) is responsible for the formation of vascular networks in vitro. However, the autocrine regulation hypothesis does not fit well with reported data on in vivo early vascular development. In this study, we propose a mathematical model based on the alternative assumption that endodermal VEGF signalling activity, having a paracrine effect on adjacent angioblasts, is mediated by its binding to the extracellular matrix (ECM). Detailed morphometric analysis of simulated networks and images obtained from in vivo quail embryos reveals the model mimics the vascular patterns with high accuracy. These results show that paracrine signalling can result in the formation of fine-grained cellular networks when mediated by angioblast-produced ECM. This lends additional support to the theory that patterning during early vascular development in the vertebrate embryo is regulated by paracrine signalling
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