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131.
Veronica Costiniti Iolanda Spera Roberta Menabò Erika M. Palmieri Alessio Menga Pasquale Scarcia Vito Porcelli Rosanna Gissi Alessandra Castegna Marcella Canton 《生物化学与生物物理学报:疾病的分子基础》2018,1864(9):3050-3059
Monoamine oxidase (MAO), a mitochondrial enzyme that oxidizes biogenic amines generating hydrogen peroxide, is a major source of oxidative stress in cardiac injury. However, the molecular mechanisms underlying its overactivation in pathological conditions are still poorly characterized.Here, we investigated whether the enhanced MAO-dependent hydrogen peroxide production can be due to increased substrate availability using a metabolomic profiling method. We identified N1-methylhistamine -the main catabolite of histamine- as an important substrate fueling MAO in Langendorff mouse hearts, directly perfused with a buffer containing hydrogen peroxide or subjected to ischemia/reperfusion protocol. Indeed, when these hearts were pretreated with the MAO inhibitor pargyline we observed N1-methylhistamine accumulation along with reduced oxidative stress. Next, we showed that synaptic terminals are the major source of N1-methylhistamine. Indeed, in vivo sympathectomy caused a decrease of N1-methylhistamine levels, which was associated with a marked protection in post-ischemic reperfused hearts. As far as the mechanism is concerned, we demonstrate that exogenous histamine is transported into isolated cardiomyocytes and triggers a rise in the levels of reactive oxygen species (ROS). Once again, pargyline pretreatment induced intracellular accumulation of N1-methylhistamine along with decrease in ROS levels. These findings uncover a receptor-independent mechanism for histamine in cardiomyocytes.In summary, our study reveals a novel and important pathophysiological causative link between MAO activation and histamine availability during pathophysiological conditions such as oxidative stress/cardiac injury. 相似文献
132.
133.
Rosanna Maccari Antonella Del Corso Paolo Paoli Ilenia Adornato Giulia Lori Francesco Balestri Mario Cappiello Alexandra Naß Gerhard Wolber Rosaria Ottanà 《Bioorganic & medicinal chemistry letters》2018,28(23-24):3712-3720
Designed multiple ligands (DMLs), developed to modulate simultaneously a number of selected targets involved in etiopathogenetic mechanisms of a multifactorial disease, such as diabetes mellitus (DM), are considered a promising alternative to combinations of drugs, when monotherapy results to be unsatisfactory. In this work, compounds 1–17 were synthesized and in vitro evaluated as DMLs directed to aldose reductase (AR) and protein tyrosine phosphatase 1B (PTP1B), two key enzymes involved in different events which are critical for the onset and progression of type 2 DM and related pathologies. Out of the tested 4-thiazolidinone derivatives, compounds 12 and 16, which exhibited potent AR inhibitory effects along with interesting inhibition of PTP1B, can be assumed as lead compounds to further optimize and balance the dual inhibitory profile. Moreover, several structural portions were identified as features that could be useful to achieve simultaneous inhibition of both human AR and PTP1B through binding to non-catalytic regions of both target enzymes. 相似文献
134.
Marina Papaianni Felice Contaldi Andrea Fulgione Sheridan L. Woo Angela Casillo Maria Michela Corsaro Ermenegilda Parrilli Luca Marcolungo Marzia Rossato Massimo Delledonne Marianna Garonzi Domenico Iannelli Rosanna Capparelli 《BMC microbiology》2018,18(1):208
Background
The study describes the Salmonella Rissen phage ?1 isolated from the ?1-sensitive Salmonella Rissen strain RW. The same phage was then used to select the resistant strain RR?1+, which can harbour or not ?1.Results
Following this approach, we found that ?1, upon excision from RW cells with mitomycin, behaves as a temperate phage: lyses host cells and generates phage particles; instead, upon spontaneous excision from RR?1+ cells, it does not generate phage particles; causes loss of phage resistance; switches the O-antigen from the smooth to the rough phenotype, and favors the transition of Salmonella Rissen from the planktonic to the biofilm growth.The RW and RR?1+ strains differ by 10 genes; of these, only two (phosphomannomutase_1 and phosphomannomutase_2; both involved in the mannose synthesis pathway) display significant differences at the expression levels. This result suggests that phage resistance is associated with these two genes.Conclusions
Phage ?1 displays the unusual property of behaving as template as well as lytic phage. This feature was used by the phage to modulate several phases of Salmonella Rissen lifestyle.135.
136.
Ermenegilda Parrilli Annarita Ricciardelli Angela Casillo Filomena Sannino Rosanna Papa Marco Tilotta Marco Artini Laura Selan Maria Michela Corsaro Maria Luisa Tutino 《Extremophiles : life under extreme conditions》2016,20(2):227-234
Microbial biofilms are mainly studied due to detrimental effects on human health but they are also well established in industrial biotechnology for the production of chemicals. Moreover, biofilm can be considered as a source of novel drugs since the conditions prevailing within biofilm can allow the production of specific metabolites. Antarctic bacterium Pseudoalteromonas haloplanktis TAC125 when grown in biofilm condition produces an anti-biofilm molecule able to inhibit the biofilm of the opportunistic pathogen Staphylococcus epidermidis. In this paper we set up a P. haloplanktis TAC125 biofilm cultivation methodology in automatic bioreactor. The biofilm cultivation was designated to obtain two goals: (1) the scale up of cell-free supernatant production in an amount necessary for the anti-biofilm molecule/s purification; (2) the recovery of P. haloplanktis TAC125 cells grown in biofilm for physiological studies. We set up a fluidized-bed reactor fermentation in which floating polystyrene supports were homogeneously mixed, exposing an optimal air–liquid interface to let bacterium biofilm formation. The proposed methodology allowed a large-scale production of anti-biofilm molecule and paved the way to study differences between P. haloplanktis TAC125 cells grown in biofilm and in planktonic conditions. In particular, the modifications occurring in the lipopolysaccharide of cells grown in biofilm were investigated. 相似文献
137.
Carla Tatone Elisabetta Benedetti Maurizio Vitti Giovanna Di Emidio Rosanna Ciriminna Maria Elena Vento Vito Cela Placido Borzì Gaspare Carta Monica Lispi Anna Maria Cimini Paolo Giovanni Artini on Behalf of Italian Society of Embryology Reproduction Research 《Journal of cellular physiology》2016,231(4):908-914
138.
139.
Codon reassignment to facilitate genetic engineering and biocontainment in the chloroplast of Chlamydomonas reinhardtii 下载免费PDF全文
There is a growing interest in the use of microalgae as low‐cost hosts for the synthesis of recombinant products such as therapeutic proteins and bioactive metabolites. In particular, the chloroplast, with its small, genetically tractable genome (plastome) and elaborate metabolism, represents an attractive platform for genetic engineering. In Chlamydomonas reinhardtii, none of the 69 protein‐coding genes in the plastome uses the stop codon UGA, therefore this spare codon can be exploited as a useful synthetic biology tool. Here, we report the assignment of the codon to one for tryptophan and show that this can be used as an effective strategy for addressing a key problem in chloroplast engineering: namely, the assembly of expression cassettes in Escherichia coli when the gene product is toxic to the bacterium. This problem arises because the prokaryotic nature of chloroplast promoters and ribosome‐binding sites used in such cassettes often results in transgene expression in E. coli, and is a potential issue when cloning genes for metabolic enzymes, antibacterial proteins and integral membrane proteins. We show that replacement of tryptophan codons with the spare codon (UGG→UGA) within a transgene prevents functional expression in E. coli and in the chloroplast, and that co‐introduction of a plastidial trnW gene carrying a modified anticodon restores function only in the latter by allowing UGA readthrough. We demonstrate the utility of this system by expressing two genes known to be highly toxic to E. coli and discuss its value in providing an enhanced level of biocontainment for transplastomic microalgae. 相似文献
140.
Pollen data collected with a Hirst spore-trap from 1981 to 1988 are presented and related to flora, vegetation and climate
of the city of Turin. A comparison of vegetational and aerosporological data collected in other European cities show that,
from this point of view, Turin is more similar to the Central-European area than to the Mediterranean one. 相似文献