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Plant roots can exploit beneficial associations with soil-inhabiting microbes, promoting growth and expanding the immune capacity of the host plant. In this work, we aimed to provide new information on changes occurring in tomato interacting with the beneficial fungus Beauveria bassiana. The tomato leaf proteome revealed perturbed molecular pathways during the establishment of the plant–fungus relationship. In the early stages of colonization (5–7 d), proteins related to defense responses to the fungus were down-regulated and proteins related to calcium transport were up-regulated. At later time points (12–19 d after colonization), up-regulation of molecular pathways linked to protein/amino acid turnover and to biosynthesis of energy compounds suggests beneficial interaction enhancing plant growth and development. At the later stage, the profile of leaf hormones and related compounds was also investigated, highlighting up-regulation of those related to plant growth and defense. Finally, B. bassiana colonization was found to improve plant resistance to Botrytis cinerea , impacting plant oxidative damage. Overall, our findings further expand current knowledge on the possible mechanisms underlying the beneficial role of B. bassiana in tomato plants. [ABSTRACT FROM AUTHOR]

FMRP is an RNA-binding protein that represses the translation of specific mRNAs. In neurons, its depletion determines the exaggerated translation of mRNAs leading to dendritic and axonal aberrant development, two peculiar features of Fragile X syndrome patients. However, how FMRP binds to translational machinery to regulate the translation of its mRNA targets is not yet fully understood. Here, we show that FMRP localizes on translational machinery by interacting with the ribosomal binding protein, Receptor for Activated C Kinase 1 (RACK1). The binding of FMRP to RACK1 removes the translational repressive activity of FMRP and promotes the translation of PSD-95 mRNA, one specific target of FMRP. This binding also results in a reduction in the level of FMRP phosphorylation. We also find that the morphological abnormalities induced by Fmr1 siRNA in cortical neurons are rescued by the overexpression of a mutant form of RACK1 that cannot bind ribosomes. Thus, these results provide a new mechanism underlying FMRP activity that contributes to altered development in FXS. Moreover, these data confirm the role of ribosomal RACK1 as a ribosomal scaffold for RNA binding proteins. [ABSTRACT FROM AUTHOR]

Mechanistic target of rapamycin (MTOR) plays a critical role in the regulation of cell growth and in the response to energy state changes. Drugs inhibiting MTOR are increasingly used in antineoplastic therapies. Myocardial MTOR activity changes during hypertrophy and heart failure (HF). However, whether MTOR exerts a positive or a negative effect on myocardial function remains to be fully elucidated. Here, we show that ablation of Mtor in the adult mouse myocardium results in a fatal, dilated cardiomyopathy that is characterized by apoptosis, autophagy, altered mitochondrial structure, and accumulation of eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1). 4E-BP1 is an MTOR-containing multi-protein complex-1 (MTORC1) substrate that inhibits translation initiation. When subjected to pressure overload, Mtor-ablated mice demonstrated an impaired hypertrophic response and accelerated HF progression. When the gene encoding 4E-BP1 was ablated together with Mtor, marked improvements were observed in apoptosis, heart function, and survival. Our results demonstrate a role for the MTORC1 signaling network in the myocardial response to stress. In particular, they highlight the role of 4E-BP1 in regulating cardiomyocyte viability and in HF. Because the effects of reduced MTOR activity were mediated through increased 4E-BP1 inhibitory activity, blunting this mechanism may represent a novel therapeutic strategy for improving cardiac function in clinical HF., Introduction Mechanistic target of rapamycin (MTOR) is a key regulator of protein synthesis in the cardiomyocyte (1, 2). Increased protein synthesis underpins hypertrophic growth, a salient feature of the heart [...]

Author(s): Marcello Ceci [1, 2]; Cristina Gaviraghi [1, 2]; Chiara Gorrini [1, 2]; Leonardo A. Sala [1, 2]; Nina Offenhäuser [3]; Pier Carlo Marchisio [1, 2]; Stefano Biffo (corresponding author) [...]

The review is an overview of the current knowledge of neuronal regeneration properties in mammals and fish. The ability to regenerate the damaged parts of the nervous tissue has been demonstrated in all vertebrates. Notably, fish and amphibians have the highest capacity for neurogenesis, whereas reptiles and birds are able to only regenerate specific regions of the brain, while mammals have reduced capacity for neurogenesis. Zebrafish (Danio rerio) is a promising model of study because lesions in the brain or complete cross-section of the spinal cord are followed by an effective neuro-regeneration that successfully restores the motor function. In the brain and the spinal cord of zebrafish, stem cell activity is always able to re-activate the molecular programs required for central nervous system regeneration. In mammals, traumatic brain injuries are followed by reduced neurogenesis and poor axonal regeneration, often insufficient to functionally restore the nervous tissue, while spinal injuries are not repaired at all. The environment that surrounds the stem cell niche constituted by connective tissue and stimulating factors, including pro-inflammation molecules, seems to be a determinant in triggering stem cell proliferation and/or the trans-differentiation of connective elements (mainly fibroblasts). Investigating and comparing the neuronal regeneration in zebrafish and mammals may lead to a better understanding of the mechanisms behind neurogenesis, and the failure of the regenerative response in mammals, first of all, the role of inflammation, considered the main inhibitor of the neuronal regeneration. [ABSTRACT FROM AUTHOR]

Zebrafish hearts can regenerate through activation of growth factors and trans-differentiation of fibroblasts, epicardial, myocardial and endocardial cells, all positive for GATA4 during the process. A possible model of regeneration of the whole heart and the regenerating cells in ex-vivo culture is presented here by a stimulation of cocktail of growth factors. In ex-vivo growth-factors-supplemented culture the heart regeneration was quite complete without signs of fibrosis. Epicardial- and endocardial-derived cells have been analyzed by electron microscopy evidencing two main types: 1) larger/prismatic and 2) small/rounded. Type (1) showed on the surface protein-sculptures, while type(2) was smooth with sparse globular proteins. To confirm their nature we have contemporarily analyzed their proliferative capability and markers-positivity. The cells treated by growth factors have at least two-fold more proliferation with GATA4-positivity. The type (1) cell evidenced WT1+(marker of embryonic epicardium); the type (2) showed NFTA2+(marker of embryonic endocardium); whereas cTNT-cardiotroponin was negative. Under growth factors stimulation, GATA4+/WT1+ and GATA4+/NFTA2+ could be suitable candidates to be the cells with capability to move in/out of the tissue, probably by using their integrins, and it opens the possibility to have long term selected culture to future characterization. [ABSTRACT FROM AUTHOR]

The article introduces JudO, an OWL2 ontology library of legal knowledge that relies on the metadata contained in judicial documents. JudO represents the interpretations performed by a judge while conducting legal reasoning towards the adjudication of a case. To the aim of this application, judicial interpretation is intended in the restricted sense of the acts of judicial subsumption performed by the judge when he considers a material instance (token in Searle's terminology), and assigns it to an abstract category (type). The ontology library is based on a theoretical model and on some specific patterns that exploit some new features introduced by OWL2. JudO provides meaningful legal semantics, while retaining a strong connection to source documents (fragments of legal texts). The application task is to enable detection and modeling of jurisprudence-related information directly from the text, and to perform shallow reasoning on the resulting knowledge base. The ontology library is also supposed to support a defeasible rule set for legal argumentation on the groundings of judicial decisions. [ABSTRACT FROM AUTHOR]

Adult neurogenesis is a multistep process regulated by several extrinsic factors, including neurotrophins. Among them, little is known about the role of nerve growth factor (NGF) in the neurogenic niches of the mouse. Here we analyzed the biology of adult neural stem cells (NSCs) from the subventricular zone (SVZ) of AD11 anti-NGF transgenic mice, in which the expression of the recombinant antibody aD11 leads to a chronic postnatal neutralization of endogenous NGF. We showed that AD11-NSCs proliferate 10-fold less, with respect to their control counterparts, and display a significant impairment in their ability to differentiate into β-tubulin positive neurons. We found a considerable reduction in the number of SVZ progenitors and neuroblasts also in vivo, which correlates with a lower number of newborn neurons in the olfactory bulbs of AD11 mice and a severe deficit in the ability of these mice to discriminate between different odors. We also demonstrated that, in AD11 mice, the morphology of both SVZ-resident and neurosphere-derived astrocytes is significantly altered. We were able to reproduce the AD11 phenotype in vitro, by acutely treating wild type NSCs with the anti-NGF antibody, further demonstrating that both the proliferation and the differentiation defects are due to the NGF deprivation. Consistently, the proliferative impairment of AD11 progenitors, as well as the atrophic morphology of AD11 astrocytes, can be partly rescued in vitro and in vivo by exogenous NGF addition. Altogether, our results demonstrate a causal link between NGF signaling and proper proliferation and differentiation of neural stem cells from the SVZ. S tem C ells 2014;32:2516-2528 [ABSTRACT FROM AUTHOR]

Male hypogonadism is a disorder characterized by low levels of testosterone, but patients can either show normal insulin (insulin-sensitive (IS)) or over time they can become insulin-resistant (IR). Since the two groups showed different altered metabolisms, testosterone replacement therapy (TRT) could achieve different results. In this paper, we analyzed plasma from 20 IS patients with low testosterone (<8 nmol/L) and HOMAi < 2.5. The samples, pre- and post-treatment with testosterone for 60 days, were analyzed by UHPLC and mass spectrometry. Glycolysis was significantly upregulated, suggesting an improved glucose utilization. Conversely, the pentose phosphate pathway was reduced, while the Krebs cycle was not used. Branched amino acids and carnosine metabolism were positively influenced, while β-oxidation of fatty acids (FFA) was not activated. Cholesterol, HDL, and lipid metabolism did not show any improvements at 60 days but did so later in the experimental period. Finally, both malate and glycerol shuttle were reduced. As a result, both NADH and ATP were significantly lower. Interestingly, a significant production of lactate was observed, which induced the activation of the Cori cycle between the liver and muscles, which became the main source of energy for these patients without involving alanine. Thus, the treatment must be integrated with chemicals which are not restored in order to reactivate energy production. [ABSTRACT FROM AUTHOR]

Nerve Growth Factor (NGF) is being considered as a therapeutic candidate for Alzheimer's disease (AD) treatment but the clinical application is hindered by its potent pro-nociceptive activity. Thus, to reduce systemic exposure that would induce pain, in recent clinical studies NGF was administered through an invasive intracerebral gene-therapy approach. Our group demonstrated the feasibility of a non-invasive intranasal delivery of NGF in a mouse model of neurodegeneration. NGF therapeutic window could be further increased if its nociceptive effects could be avoided altogether. In this study we exploit forms of NGF, mutated at residue R100, inspired by the human genetic disease HSAN V (Hereditary Sensory Autonomic Neuropathy Type V), which would allow increasing the dose of NGF without triggering pain. We show that "painless" hNGF displays full neurotrophic and anti-amyloidogenic activities in neuronal cultures, and a reduced nociceptive activity in vivo. When administered intranasally to APPxPS1 mice ( n = 8), hNGFP61S/R100E prevents the progress of neurodegeneration and of behavioral deficits. These results demonstrate the in vivo neuroprotective and antiamyloidogenic properties of hNGFR100 mutants and provide a rational basis for the development of "painless" hNGF variants as a new generation of therapeutics for neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

In neurons, specific mRNAs are transported in a translationally repressed manner along dendrites or axons by transport ribonucleic-protein complexes called RNA granules. ZBP1 is one RNA binding protein present in transport RNPs, where it transports and represses the translation of cotransported mRNAs, including b-actin mRNA. The release of β-actin mRNA from ZBP1 and its subsequent translation depends on the phosphorylation of ZBP1 by Src kinase, but little is known about how this process is regulated. Here we demonstrate that the ribosomal-associated protein RACK1, another substrate of Src, binds the β-actin mRNA/ZBP1 complex on ribosomes and contributes to the release of β-actin mRNA from ZBP1 and to its translation. We identify the Src binding and phosphorylation site Y246 on RACK1 as the critical site for the binding to the bactin mRNA/ZBP1 complex. Based on these results we propose RACK1 as a ribosomal scaffold protein for specific mRNA-RBP complexes to tightly regulate the translation of specific mRNAs. [ABSTRACT FROM AUTHOR]

During adulthood, the neurotrophin Nerve Growth Factor (NGF) sensitizes nociceptors, thereby increasing the response to noxious stimuli. The relationship between NGF and pain is supported by genetic evidence: mutations in the NGF TrkA receptor in patients affected by an hereditary rare disease (Hereditary Sensory and Autonomic Neuropathy type IV, HSAN IV) determine a congenital form of severe pain insensitivity, with mental retardation, while a mutation in NGFB gene, leading to the aminoacid substitution R100W in mature NGF, determines a similar loss of pain perception, without overt cognitive neurological defects (HSAN V). The R100W mutation provokes a reduced processing of proNGF to mature NGF in cultured cells and a higher percentage of neurotrophin secreted is in the proNGF form. Moreover, using Surface Plasmon Resonance we showed that the R100W mutation does not affect NGF binding to TrkA, while it abolishes NGF binding to p75NTR receptors. However, it remains to be clarified whether the major impact of the mutation is on the biological function of proNGF or of mature NGF and to what extent the effects of the R100W mutation on the HSAN V clinical phenotype are developmental, or whether they reflect an impaired effectiveness of NGF to regulate and mediate nociceptive transmission in adult sensory neurons. Here we show that the R100 mutation selectively alters some of the signaling pathways activated downstream of TrkA NGF receptors. NGFR100 mutants maintain identical neurotrophic and neuroprotective properties in a variety of cell assays, while displaying a significantly reduced pain-inducing activity in vivo (n = 8-10 mice/group). We also show that proNGF has a significantly reduced nociceptive activity, with respect to NGF. Both sets of results jointly contribute to elucidating the mechanisms underlying the clinical HSAN V manifestations, and to clarifying which receptors and intracellular signaling cascades participate in the pain sensitizing action of NGF. [ABSTRACT FROM AUTHOR]

The article reports on the study of the mechanisms of excitation-contraction (EC) coupling defects in cardiomyocytes from mice with type 2 diabetes. It notes that the study aims to identify if 13 weeks of aerobic interval training could restore cardiomyocyte cycling and EC coupling. It presents the methods and results of the study wherein it concludes that aerobic interval training returned the contractile function of the diabetic cardiomyocyte.

Cigarette smoke contains hundreds of potentially toxic compounds and is an important risk factor for cardiovascular disease. However, the key components responsible for endothelial and myocardial dysfunction have not been fully identified. The objective of the present study was to determine the cardiovascular effects of long-term inhalation of carbon monoxide (CO) administrated to give concentrations in the blood similar to those observed in heavy smokers. Female rats were exposed to either CO or air (control group) (n = 12). The CO group was exposed to 200 ppm CO (100 h/wk) for 18 mo. Rats exposed to CO had 24% lower maximal oxygen uptake, longer (145 vs. 123 μ m) and wider (47 vs. 25 μ m) cardiomyocytes, reduced cardiomyocyte fractional shortening (12 vs. 7%), and 26% longer time to 50% re-lengthening than controls. In addition, cardiomyocytes from CO-exposed rats had 48% lower intracellular calcium (Ca2 +) amplitude, 22% longer time to Ca2 + decay, 34% lower capacity of sarcoplasmic reticulum Ca2 +-ATPase (SERCA2a), and 37% less t-tubule area compared to controls. Phosphorylation levels of phospholamban at Ser16 and Thr17 were significantly reduced in the CO group, whereas total concentration of phospholamban and SERCA2a were unchanged. Cardiac atrial natriuretic peptide, vascular endothelial growth factor, cyclic guanosine monophosphate, calcineurin, calmodulin, pERK, and pS6 increased, whereas pAkt and pCaMKII δ remained unchanged by CO. Endothelial function and systemic blood pressure were not affected by CO exposure. Long-term CO exposure reduces aerobe capacity and contractile function and leads to pathological hypertrophy. Impaired Ca2 + handling and increased growth factor signaling seem to be responsible for these pathological changes. [ABSTRACT FROM AUTHOR]

Cardiomyocyte hypertrophy differs according to the stress exerted on the myocardium. While pressure overload-induced cardiomyocyte hypertrophy is associated with depressed contractile function, physiological hypertrophy after exercise training associates with preserved or increased inotropy. We determined the activation state of myocardial Akt signaling with downstream substrates and fetal gene reactivation in exercise-induced physiological and pressure overload-induced pathological hypertrophies. C57BL/6J mice were either treadmill trained for 6 weeks, 5 days/week, at 85–90% of maximal oxygen uptake (VO2max), or underwent transverse aortic constriction (TAC) for 1 or 8 weeks. Total and phosphorylated protein levels were determined with SDS-PAGE, and fetal genes by real-time RT-PCR. In the physiologically hypertrophied heart after exercise training, total Akt protein level was unchanged, but Akt was chronically hyperphosphorylated at serine 473. This was accompanied by activation of the mammalian target of rapamycin (mTOR), measured as phosphorylation of its two substrates: the ribosomal protein S6 kinase-1 (S6K1) and the eukaryotic translation initiation factor-4E binding protein-1 (4E-BP1). Exercise training did not reactivate the fetal gene program (β-myosin heavy chain, atrial natriuretic factor, skeletal muscle actin). In contrast, pressure overload after TAC reactivated fetal genes already after 1 week, and partially inactivated the Akt/mTOR pathway and downstream substrates after 8 weeks. In conclusion, changes in opposite directions of the myocardial Akt/mTOR signal pathway appears to distinguish between physiological and pathological hypertrophies; exercise training associating with activation and pressure overload associating with inactivation of the Akt/mTOR pathway. J. Cell. Physiol. 214: 316–321, 2008. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Abstract: Tif6p (eIF6) is necessary for 60S biogenesis, rRNA maturation and must be released from 60S to permit 80S assembly and translation. We characterized Tif6p interactors. Tif6p is mostly on 66S–60S pre-ribosomes, partly free. Tif6p complex(es) contain nucleo-ribosomal factors and Asc1p. Surprisingly, Tif6p particle contains the low-abundance endonuclease Sen34p. We analyzed Sen34p role on rRNA/tRNA synthesis, in vivo. Sen34p depletion impairs tRNA splicing and causes unexpected 80S accumulation. Accordingly, Sen34p overexpression causes 80S decrease and increased polysomes which suggest increased translational efficiency. With delayed kinetics, Sen34p depletion impairs rRNA processing. We conclude that Sen34p is absolutely required for tRNA splicing and that it is a rate-limiting element for efficient translation. Finally, we confirm that Tif6p accompanies 27S pre-rRNA maturation to 25S rRNA and we suggest that Sen34p endonuclease in Tif6p complex may affect also rRNA maturation. [Copyright &y& Elsevier]

The assembly of 80S ribosomes requires joining of the 40S and 60S subunits, which is triggered by the formation of an initiation complex on the 40S subunit. This event is rate-limiting for translation, and depends on external stimuli and the status of the cell. Here we show that 60S subunits are activated by release of eIF6 (also termed p27BBP). In the cytoplasm, eIF6 is bound to free 60S but not to 80S. Furthermore, eIF6 interacts in the cytoplasm with RACK1, a receptor for activated protein kinase C (PKC). RACK1 is a major component of translating ribosomes, which harbour significant amounts of PKC. Loading 60S subunits with eIF6 caused a dose-dependent translational block and impairment of 80S formation, which were reversed by expression of RACK1 and stimulation of PKC in vivo and in vitro. PKC stimulation led to eIF6 phosphorylation, and mutation of a serine residue in the carboxy terminus of eIF6 impaired RACK1/PKC-mediated translational rescue. We propose that eIF6 release regulates subunit joining, and that RACK1 provides a physical and functional link between PKC signalling and ribosome activation. [ABSTRACT FROM AUTHOR]

p27BBP/eIF6 is an evolutionarily conserved protein necessary for ribosome biogenesis which was cloned in mammals for its ability to bind the cytodomain of β4 integrin. In cultured cells, a conspicuous fraction of p27BBP/eIF6 is associated with the intermediate filaments/nuclear matrix (IF/NM) cytoskeleton. The mechanism of this association is not known. Here we show that in epidermis p27BBP/eIF6 is naturally associated with IF/NM. To analyze the intrinsic capability of p27BBP/eIF6 to generate cytoskeletal networks, the properties of the pure, recombinant, untagged protein were studied. Recombinant p27BBP/eIF6 binds β4 integrin. Upon dialysis against IF buffer, p27BBP/eIF6 forms polymers which, strikingly, have a morphology identical to NM filaments. Cross-linking experiments suggested that polymerization is favored by the formation of disulphide bridges. These data suggest that p27BBP/eIF6 is associated with the cytoskeleton, and contributes to formation of NM filaments. These findings help to settle the controversy on nuclear matrix. [Copyright &y& Elsevier]

Aberrant production of reactive oxygen species (ROS) is a common feature of damaged retinal neurons in diabetic retinopathy, and antioxidants may exert both preventive and therapeutic action. To evaluate the beneficial and antioxidant properties of food supplementation with Lisosan G, a powder of bran and germ of grain (Triticum aestivum) obtained by fermentation with selected lactobacillus and natural yeast strains, we used an in vivo model of hyperglycemia-induced retinal damage, the fruit fly Drosophila melanogaster fed with high-sucrose diet. Lisosan G positively affected the visual system of hyperglycemic flies at structural/functional level, decreased apoptosis, and reactivated protective autophagy at the retina internal network. Also, in high sucrose-fed Drosophila, Lisosan G reduced the levels of brain ROS and retina peroxynitrite. The analysis of oxidative stress-related metabolites suggested 7,8-dihydrofolate, uric acid, dihydroorotate, γ-L-glutamyl-L-cysteine, allantoin, cysteinyl-glycine, and quinolate as key mediators of Lisosan G-induced inhibition of neuronal ROS, along with the upregulation of glutathione system. Of note, Lisosan G may impact oxidative stress and the ensuing retinal cell death, also independently from autophagy, although the autophagy-ROS cross-talk is critical. This study demonstrated that the continuous supplementation with the alimentary integrator Lisosan G exerts a robust and multifaceted antioxidant effect on retinal neurons, thus providing efficacious neuroprotection of hyperglycemic eye. [ABSTRACT FROM AUTHOR]

Cardiomyocytes adapt to physical stress by increasing their size while maintaining cell function. The serine/threonine kinase Akt plays a critical role in this process of adaptation. We previously reported that transgenic overexpression of an active form of Akt (Akt-E4AI)K) in mice results in increased cardiac contractility and cell size, as well as improved sarcoplasmic reticulum (SR) Ca2+ handling. Because it is not fully elucidated, we decided to study the molecular mechanism by which Akt-E40K overexpression improves SR Ca2+ handling. To this end, SR Ca2+ uptake and the phosphorylation status of phospholamban (PLN) were evaluated in heart extracts from wild-type and Akt-E40K mice and mice harboring inducible and cardiac specffic knock-out of phosphatidylinositol-dependent kinase-1, the upstream activator of Akt. Moreover, the effect of Akt was assessed in vitro by overexpressing a mutant Akt targeted preferentially to the SR, and by biochemical assays to evaluate potential interaction with PLN. We found that when activated, Akt interacts with and phosphorylates PLN at Thr17, the Ca2+-calmodulin-dependent kinase IIδ site, whereas silencing Akt signaling, through the knock-out of phosphatidylinositol-dependent kinase-1, resulted in reduced phosphorylation of PLN at Thr17. Furthermore, overexpression of SR-targeted Akt in cardiomyocytes improved Ca2+ handling without affecting cell size. Thus, we describe here a new mechanism whereby the preferential translocation of Akt to the SR is responsible for enhancement of contractility without stimulation of hypertrophy. [ABSTRACT FROM AUTHOR]

Abstract: Cardiac adaptation to aerobic exercise training includes improved cardiomyocyte contractility and calcium handling. Our objective was to determine whether cytosolic calcium/calmodulin-dependent kinase II and its downstream targets are modulated by exercise training. A six-week aerobic interval training program by treadmill running increased maximal oxygen uptake by 35% in adult mice, whereupon left ventricular cardiomyocyte function was studied and myocardial tissue samples were used for biochemical analysis. Cardiomyocytes from trained mice had enhanced contractility and faster relaxation rates, which coincided with larger amplitude and faster decay of the calcium transient, but not increased peak systolic calcium levels. These changes were associated with reduced phospholamban expression relative to sarcoplasmic reticulum calcium ATPase and constitutively increased phosphorylation of phospholamban at the threonine 17, but not at the serine 16 site. Calcium/calmodulin-dependent kinase IIδ phosphorylation was increased at threonine 287, indicating activation. To investigate the physiological role of calcium/calmodulin-dependent kinase IIδ phosphorylation, this kinase was blocked specifically by autocamtide-2 related inhibitory peptide II. This maneuver completely abolished training-induced improvements of cardiomyocyte contractility and calcium handling and blunted, but did not completely abolish the training-induced increase in Ca2+ sensitivity. Also, inhibition of calcium/calmodulin-dependent kinase II reduced the greater frequency-dependent acceleration of relaxation that was observed after aerobic interval training. These observations indicate that calcium/calmodulin-dependent kinase IIδ contributes significantly to the functional adaptation of the cardiomyocyte to regular exercise training. [Copyright &y& Elsevier]

Abstract Neuroblastoma is the most frequent solid tumor among those diagnosed during infancy and like most tumors, it is characterized by elevated rates of cell proliferation, migration and invasion. RACK1 is among the top 10 genes identified for unfavorable prognosis at 5 years in neuroblastoma cases and its depletion negatively affects proliferation, invasion and migration. Here, we show that the ribosomal localization of RACK1 modulates the proliferation of SH-SY5Y neuroblastoma cells by regulating the expression of cell cycle genes, such as Cyclin D1, D3 and B1 independently of global translation increase. Ribosomal RACK1 is not involved in general protein synthesis, which is instead dependent on total RACK1 and PKC but independent from mTOR. Thus, ribosomal RACK1 may represent a new target to develop more efficient therapies for neuroblastoma treatment. Highlights • Ribosomal RACK1 controls proliferation of neuroblastoma cells. • The increase in proliferation is independen of up-regulation of global translation. • Ribosomal RACK1 does not regulate general protein synthesis. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • High level of metals act as apoptotic process inductor on several key tissues. • HSP70 and metalloprotein are able scarcely to block the apoptosis process. • BKPME, POPs and PAH induce in fish high levels of apoptosis. • Insecticides are in grade to provoked apoptosis in liver, gonads, kidney and blood. • Biological compounds, like bacterial-lypopolysaccaride are able to induce apoptosis. Abstract The industrial wastes, sewage effluents, agricultural run-off and decomposition of biological waste may cause high environmental concentration of chemicals that can interfere with the cell cycle activating the programmed process of cells death (apoptosis). In order to provide a detailed understanding of environmental pollutants-induced apoptosis, here we reviewed the current knowledge on the interactions of environmental chemicals and programmed cell death. Metals (aluminum, arsenic, cadmium, chromium, cobalt, zinc, copper, mercury and silver) as well as other chemicals including bleached kraft pulp mill effluent (BKME), persistent organic pollutants (POPs), and pesticides (organo-phosphated, organo-chlorinated, carbamates, phyretroids and biopesticides) were evaluated in relation to apoptotic pathways, heat shock proteins and metallothioneins. Although research performed over the past decades has improved our understanding of processes involved in apoptosis in fish, yet there is lack of knowledge on associations between environmental pollutants and apoptosis. Thus, this review could be useful tool to study the cytotoxic/apoptotic effects of different pollutants in fish species. [ABSTRACT FROM AUTHOR]

Cardiac hypertrophy is determined by an increase of cell size in cardiomyocytes (CMCs). Among the cellular processes regulating the growth of cell size, the increase of protein synthesis rate represents a critical event. Most of translational factors promoting protein synthesis stimulate cardiac hypertrophy. In contrast, activity of translational repressor factors, in cardiac hypertrophy, is not fully determined yet. Here we report the effect of a translational modulator, eIF6/p27 BBP in the hypertrophy of neonatal rat CMCs. The increase of eIF6 levels surprisingly prevent the growth of cell size induced by phenylephrine, through a block of protein synthesis without affecting skeletal rearrangement and ANF mRNA expression. Thus, this work uncovers a new translational cardiac regulator independent by other well-known factors such as mTOR signalling or eIF2β. [ABSTRACT FROM AUTHOR]

Mechanistic target of rapamycin (MTOR) plays a critical role in the regulation of cell growth and in the response to energy state changes. Drugs inhibiting MTOR are increasingly used in antineoplastic therapies. Myocardial MTOR activity changes during hypertrophy and heart failure (HF). However, whether MTOR exerts a positive or a negative effect on myocardial function remains to be fully elucidated. Here, we show that ablation of Mtor in the adult mouse myocardium results in a fatal, dilated cardiomyopathy that is characterized by apoptosis, autophagy, altered mitochondrial structure, and accumulation of eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1). 4E-BP1 is an MTOR-containing multiprotein complex-1 (MTORC1) substrate that inhibits translation initiation. When subjected to pressure overload, Mtor-ablated mice demonstrated an impaired hypertrophic response and accelerated HF progression. When the gene encoding 4E-BP1 was ablated together with Mtor, marked improvements were observed in apoptosis, heart function, and survival. Our results demonstrate a role for the MTORC1 signaling network in the myocardial response to stress. In particular, they highlight the role of 4E-BP1 in regulating cardiomyocyte viability and in HF. Because the effects of reduced MTOR activity were mediated through increased 4E-BP1 inhibitory activity, blunting this mechanism may represent a novel therapeutic strategy for improving cardiac function in clinical HF. [ABSTRACT FROM AUTHOR]

Abstract: Nerve Growth Factor (NGF) signalling is mediated by the TrkA and p75NTR receptors. Besides its neurotrophic and survival activities, NGF displays a potent pro-nociceptive activity. Recently, a missense point mutation was found in the NGFB gene (C661T, leading to the aminoacid substitution R100W) of individuals affected by a form of hereditary loss of pain perception (hereditary sensory and autonomic neuropathy type V, HSAN V). In order to gain insights into the functional consequences of the HSAN V NGF mutation, two sets of hNGFR100 mutants were expressed in Escherichia coli and purified, as mature NGF or proNGF, for in vitro receptor binding studies. Here, we show by Surface Plasmon Resonance analysis that the R100 mutation selectively disrupts binding of hNGF to p75NTR receptor, to an extent which depends on the substituting residue at position 100, while the affinity of hNGFR100 mutants for TrkA receptor is not affected. As for unprocessed hproNGF, the binding of the R100 variants to p75NTR receptor shows only a limited impairment, showing that the impact of the R100 mutation on p75NTR receptor binding is greater in the context of mature, processed hNGF. These results provide a basis for elucidating the mechanisms underlying the clinical manifestations of HSAN V patients, and provide a basis for the development of “painless” hNGF molecules with therapeutic potential. [Copyright &y& Elsevier]

Abstract: Reduced Ca2+ release from the sarcoplasmic reticulum (SR) and a negative force–frequency relation characterize end-stage human heart failure. The MLP–/– mouse with dilated cardiomyopathy is used as a model to explore novel therapeutic interventions but the alterations in Ca2+ handling in MLP–/– remain incompletely understood. We studied [Ca2+]i in left ventricular myocytes from MLP–/– and WT mice (3–4 months old; whole-cell voltage clamp, 30 °C). At 1 Hz stimulation, the amplitude of [Ca2+]i transients was similar. However, in contrast to WT, at higher frequencies the [Ca2+]i transient amplitude declined in MLP–/– and there was no increase in SR Ca2+ content. Unexpectedly, the decline of [Ca2+]i was faster in MLP–/– than in WT (at 1 Hz, τ of 80 ± 9 vs. 174 ± 29 ms, P < 0.001) and the frequency-dependent acceleration of the decline was abolished suggesting an enhanced basal SERCA activity. Indeed, the Ca2+ affinity of SR Ca2+ uptake in homogenates was higher in MLP–/–, with the maximal uptake rate similar to WT. Phosphorylation of phospholamban in MLP–/– was increased (2.3-fold at Ser16 and 2.9-fold at the Thr17 site, P < 0.001) with similar SERCA and total phospholamban protein levels. On increasing stimulation frequency to 4 Hz, WT, but not MLP–/–, myocytes had a net gain of Ca2+, suggesting inadequate Ca2+ sequestration in MLP–/–. In conclusion, increased baseline phosphorylation of phospholamban in MLP–/– leads to a reduced reserve for frequency-dependent increase of Ca2+ release. This represents a novel paradigm for altered Ca2+ handling in heart failure, underscoring the importance of phosphorylation pathways. [Copyright &y& Elsevier]

The main hallmark of many forms of familiar and sporadic amyotrophic lateral sclerosis (ALS) is a reduction in nuclear TDP-43 protein and its inclusion in cytoplasmic aggregates in motor neurons. In order to understand which cellular and molecular mechanisms underlie the mislocalization of TDP-43, we examined human skin fibroblasts from two individuals with familial ALS, both with mutations in TDP-43, and two individuals with sporadic ALS, both without TDP-43 mutations or mutations in other ALS related genes. We found that all ALS fibroblasts had a partially cytoplasmic localization of TDP-43 and had reduced cell metabolism as compared to fibroblasts from apparently healthy individuals. ALS fibroblasts showed an increase in global protein synthesis and an increase in 4E-BP1 and rpS6 phosphorylation, which is indicative of mTORC1 activity. We also observed a decrease in glutathione (GSH), which suggests that oxidative stress is elevated in ALS. ERK1/2 activity regulated the extent of oxidative stress and the localization of TDP-43 in the cytoplasm in all ALS fibroblasts. Lastly, ALS fibroblasts showed reduced stress granule formation in response to H 2 O 2 stress. In conclusion, these findings identify specific cellular and molecular defects in ALS fibroblasts, thus providing insight into potential mechanisms that may also occur in degenerating motor neurons. • ALS human skin fibroblasts have reduced cell viability and replicate rapidly • Elevated mTOR activity results in increased global translation in ALS fibroblasts • Oxidative stress activates ERK1/2, leading to cytoplasmic TDP-43 in ALS fibroblasts • ALS results in the impairment of stress granule formation [ABSTRACT FROM AUTHOR]