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Abundant evidence for translation within the 5′ leaders of many human genes is rapidly emerging, especially, because of the advent of ribosome profiling. In most cases, it is believed that the act of translation rather than the encoded peptide is important. However, the wealth of available sequencing data in recent years allows phylogenetic detection of sequences within 5′ leaders that have emerged under coding constraint and therefore allow for the prediction of functional 5′ leader translation. Using this approach, we previously predicted a CUG-initiated, 173 amino acid N-terminal extension to the human tumour suppressor PTEN. Here, a systematic experimental analysis of translation events in the PTEN 5′ leader identifies at least two additional non-AUG-initiated PTEN proteoforms that are expressed in most human cell lines tested. The most abundant extended PTEN proteoform initiates at a conserved AUU codon and extends the canonical AUG-initiated PTEN by 146 amino acids. All N-terminally extended PTEN proteoforms tested retain the ability to downregulate the PI3K pathway. We also provide evidence for the translation of two conserved AUG-initiated upstream open reading frames within the PTEN 5′ leader that control the ratio of PTEN proteoforms.

Most of the microbial cells on earth under natural conditions exist in a dormant condition, commonly known as quiescent state. Quiescent cells exhibit low rates of transcription and translation suggesting that cellular abundance of proteins may be similar in quiescent cells. Therefore, this study aim to compare the proteome of budding yeast cells from two quiescent states viz. stationary phase/G0 and tetrads. Using iTRAQ (isobaric tag for relative and absolute quantitation) based quantitative proteomics we identified 289 proteins, among which around 40 proteins exhibited ±1.5 fold change consistently from the four biological replicates. Proteomics data was validated by western blot and denstiometric analysis of Hsp12 and Spg4. Level of budding yeast 14-3-3 proteins was found to be similar in both the quiescent states, whereas Hsp12 and Spg4 expressed only during stress. FACS (fluorescence-activated cell sorting) analysis showed that budding yeast cells were arrested at G1 stages both in tetrads as well as in stationary phase. We also observed that quiescent states did not express Ime1 (inducer of meiosis). Taken together, our present study demonstrates that the cells in quiescent state may have similar proteome and accumulation of proteins like Hsp12, Hsp26 and Spg4 may play an important role in retaining viability of the cells during dormancy.

The transcription factor hypoxia-inducible factor (HIF)-1 plays a central physiological role in oxygen and energy homeostasis, and is activated during hypoxia by stabilization of the subunit HIF-1 alpha. Activation can also occur by proinflammatory cytokines during inflammation. Hypoxia, as well as proinflammatory cytokines, plays an important role in the synovia in rheumatoid arthritis (RA) patients. Expression of HIF-1 alpha has been demonstrated in RA synovial lining layer. The aim of the study was to investigate the regulation of the intracellular signal transduction pathways, involved in the expression of HIF-1 alpha, and in the expression of genes regulated by HIF-1 alpha in rheumatoid synovial fibroblasts (RSF). RSF were cultured under proinflammatory conditions (IL-1 beta and TNF-alpha stimulation) and under chemical hypoxia (CoCl2 treatment). Expression of HIF-1 alpha was analyzed in nuclear extracts by Western blotting. The effect of inhibitors of the PI3K and the ERK pathway on HIF-1 alpha protein expression was measured. mRNA expression of HIF-1 alpha, COX-2, vascular endothelial growth factor (VEGF), and stromal cell-derived factor (SDF)-1 was determined by real-time RT-PCR, and protein production of VEGF and SDF-1 by ELISA. Treatment of the synovial fibroblasts with 150 MM CoCl2 as well as stimulation with 10 ng/mL IL-1 beta or TNF-alpha resulted in strong protein expression of HIF-1 alpha, measured with Western blotting. Pretreatment with the MEK1/2 inhibitor PD98059 as well as the PI3K inhibitor LY294002 resulted in inhibition of the cytokine-induced HIF-1 alpha expression. Furthermore, it was shown that cytokine-induced mRNA expression of HIF-1 alpha was inhibited by the PI3K inhibitor. We found that cytokine stimulation induced VEGF mRNA and protein production, but no significant effect of kinase inhibition was found on VEGF production in cytokine-stimulated RSF, Both the ERK pathway and the PI3K pathway are involved in the cytokine-induced HIF-1 alpha expression in RSF and in the expression of proangiogenic factors.

Insulin regulates glycaemia, lipogenesis and increases mRNA translation. Cells with reduced eukaryotic initiation factor 6 (eIF6) do not increase translation in response to insulin. The role of insulin-regulated translation is unknown. Here we show that reduction of insulin-regulated translation in mice heterozygous for eIF6 results in normal glycaemia, but less blood cholesterol and triglycerides. eIF6 controls fatty acid synthesis and glycolysis in a cell autonomous fashion. eIF6 acts by exerting translational control of adipogenic transcription factors like C/EBPβ, C/EBPδ and ATF4 that have G/C rich or uORF sequences in their 5′ UTR. The outcome of the translational activation by eIF6 is a reshaping of gene expression with increased levels of lipogenic and glycolytic enzymes. Finally, eIF6 levels modulate histone acetylation and amounts of rate-limiting fatty acid synthase (Fasn) mRNA. Since obesity, type 2 diabetes, and cancer require a Fasn-driven lipogenic state, we propose that eIF6 could be a therapeutic target for these diseases., Insulin enhances mRNA translation via the translation initiation factor eIF6. Here, Brina et al. show that insulin-mediated activation of eIF6 is associated with the selective translation of genes involved in glycolysis and lipid synthesis with characteristic G/C-rich and uORF sequences in their mRNA.

The Isolated Perfused Liver (IPL) model is a widely used and appreciated in vitro method to demonstrate liver viability and metabolism. Reperfusion is performed in a controlled setting, however, via the portal vein only. To study transplant related questions concerning bile and transport of bile, the in vitro Isolated dual Perfused Liver model is revisited. The IdPL is an in vitro reperfusion model, using both portal vein and hepatic artery. Livers from 12 Wistar rats were flushed with University of Wisconsin-organ preservation solution, procured and reperfused in either the conventional IPL-model (n=6) or the new IdPL-model (n=6). Liver injury, assessed by the release of aspartate amino transferase and lactate dehydrogenase, showed similar levels during both IPL and IdPL reperfusion, only alanine amino transferase showed an improvement. Cumulative bile production showed an improvement: 176.3 +/- 8.4 in the IdPL compared to 126.1 +/- 12.2 mu g/g-liver in the IPL (p

Cell cycle events in embryo axes of Norway maple (Acer platanoides L.) seeds were studied during dormancy breaking by flow cytometric analyses of the nuclear DNA content and by immunodetection of beta-tubulin. Most embryonic nuclei of dry, fully matured seeds were arrested in the G(2) phase of the cell cycle. In addition, the lowest content of beta-tubulin was detected in dry, mature seeds. Imbibition in water and cold stratification resulted in a decrease in the number of nuclei in G(2), and a simultaneous increase in beta-tubulin content. In germinated seeds the content of beta-tubulin was the highest and the number of cells in G(2) was the lowest. Both cell cycle events preceded cell expansion and division and subsequent growth of the radicle through the seed coat. The anatomical investigation has proved that the main reason for decrease in the number of nuclei in G(2) is mitosis, started with seeds germination ( radicle protrusion). The activation of the cell cycle and the beta-tubulin accumulation were associated with embryo dormancy breaking.

Hypothesis: Early burn wound excision modulates the hypermetabolic response in severe pediatric burn injuries.Design: Before-after trial.Setting: A 30-bed burn referral center in a private, university-affiliated hospital.Methods: We studied 35 severely burned children who were divided into 2 groups. One group (n = 20) was treated with early burn wound excision within 24 hours after the injury. The second group (n = 15) was treated conservatively with silver sulfadiazine in other burn facilities for 5 days, and burn wounds were surgically excised when patients were admitted to our burn center on day 6 after the injury. Data compiled included oxygen consumption and acute-phase protein, interleukin 1beta; interleukin 6, interleukin 10, tumor necrosis factor alpha, and anabolic hormone (growth hormone, insulinlike growth factor type 1) levels preoperatively and 24 hours and 5 days postoperatively.Main Outcome Measures: Acute-phase and hypermetabolic responses.Results: Early burn wound excision abrogated the hypermetabolic response in pediatric burn patients. Patients who underwent conservative treatment had a significantly more severe inflammatory and hypermetabolic response at the same time interval and significantly lower levels of anabolic hormones.Conclusions: Early burn wound excision is a safe therapeutic approach that modulates the hypermetabolic response after burn injury. It was superior to the conservative treatment of silver sulfadiazine and delayed excision, and it should be considered when treating all severe full-thickness burns.

Complete cDNA sequences were obtained for ribosomal protein (rp) L15 and eukaryotic initiation factor eIF2alpha from the lepidopteran insect Spodoptera frugiperda, and for elongation factor eEF2 from S. exigua. The presence of a 5' terminal oligopyrimidine (TOP) tract classified the lepidopteran rpL15 transcript as a TOP mRNA. For eEF2, two types of transcripts were observed, one of which had a 5'TOP tract. The transcript levels for rpL15, eEF2 and eIF2alpha decreased following baculovirus infection. Polysome analysis showed that the corresponding mRNAs remained to be translated until at least 16 h post-infection for both TOP and non-TOP mRNAs. Baculovirus-induced host shut-off therefore appears to be regulated at the level of RNA abundance rather than at the translational level.

The activity of heterotrophic soil microorganisms is usually limited by the availability and quality of carbon (C). Adding organic substances will thus trigger a microbial response. We studied the response in bacterial growth and respiration after the addition of low amounts of glucose. First we determined if additions of glucose, at concentrations which did not result in an exponential increase in respiration after the lag phase, still stimulated bacterial growth. The second aim was to determine the threshold concentration of glucose needed to induce bacterial growth. Adding glucose-C at 1000 mu g g(-1) soil resulted in an increased respiration rate, which was stable during 12 h, and then decreased without showing any exponential increase in respiration. Bacterial growth, determined as leucine incorporation, did not change compared to an unamended control during the first 12 h, but then increased to levels 5 times higher than in the control. Thus, after the lag phase, a period with increasing bacterial growth, but at the same time decreasing respiration rates, was found. Similar results, but with a more modest increase in bacterial growth, were found using 500 mu g glucose-C g(-1) soil. Adding 50-700 mu g glucose-C g(-1) resulted in increased respiration during 24 h correlating with the addition rate. In contrast, bacterial growth after 24 h was only stimulated by glucose additions >200 mu g C g(-1) soil. Thus, there was a threshold concentration of added substrate for inducing bacterial growth. Below the threshold concentration growth and respiration appear to be uncoupled. (C) 2014 Elsevier Ltd. All rights reserved.

We discovered a chromosomal locus containing 2 toxin-antitoxin modules (TAs) with an antisense transcriptional organization in the E. faecalis clinical isolate V583. These TAs are homologous to the type I txpA-ratA system and the type II mazEF, respectively. We have shown that the putative MazF is toxic for E. coli and triggers RNA degradation, and its cognate antitoxin MazE counteracts toxicity. The second module, adjacent to mazEF, expresses a toxin predicted to belong to the TxpA type I family found in Firmicutes, and the antisense RNA antidote, RatA. Genomic analysis indicates that the cis-association of mazEF and txpA-ratA modules has been favored during evolution, suggesting a selective advantage for this TA organization in the E. faecalis species. We showed regulatory interplays between the 2 modules, involving transcription control and RNA stability. Remarkably, our data reveal that MazE and MazEF have a dual transcriptional activity: they act as autorepressors and activate ratA transcription, most likely in a direct manner. RatA controls txpA RNA levels through stability. Our data suggest a pivotal role of MazEF in the coordinated expression of mazEF and txpA-ratA modules in V583. To our knowledge, this is the first report describing a crosstalk between type I and II TAs.

© 2015 International Society for Microbial Ecology All rights reserved. Functional genomics of diatom-dominated communities fromthe Antarctic Peninsula was studied using comparative metatranscriptomics. Samples obtained from diatom-rich communities in the Bransfield Strait, the western Weddell Sea and sea ice in the Bellingshausen Sea/Wilkins Ice Shelf yielded more than 500K pyrosequencing reads that were combined to produce a global metatranscriptome assembly. Multi-gene phylogenies recovered three distinct communities, and diatom-assigned contigs further indicated little read-sharing between communities, validating an assembly-based annotation and analysis approach. Although functional analysis recovered a core of abundant shared annotations that were expressed across the three diatom communities, over 40% of annotations (but accounting for 3 - uptake and utilization all pointed to irradiance stress and/or inorganic carbon limitation within sea ice. Ice-binding proteins and cold-shock transcription factors were also enriched in sea ice diatoms. Surprisingly, the abundance of gene transcripts for the translational machinery tracked decreasing environmental temperature across only a 4 °C range, possibly reflecting constraints on translational efficiency and protein production in cold environments., This work was supported by grants 'SOPA' from the Portuguese Science Foundation (FCT; PTDC/MAR/72630) to GAP and is a contribution to the ATOS project (POL2006-00550/CTM) funded by the Spanish Ministry of Economy and Competitiveness (under the scope of the International Polar Year (IPY))

The recovery from many injuries sustained in athletic training or competition often requires an extensive period of limb immobilisation (muscle disuse). Such periods induce skeletal muscle loss and consequent declines in metabolic health and functional capacity, particularly during the early stages (1-2 weeks) of muscle disuse. The extent of muscle loss during injury strongly influences the level and duration of rehabilitation required. Currently, however, efforts to intervene and attenuate muscle loss during the initial two weeks of injury are minimal. Mechanistically, muscle disuse atrophy is primarily attributed to a decline in basal muscle protein synthesis rate and the development of anabolic resistance to food intake. Dietary protein consumption is of critical importance for stimulating muscle protein synthesis rates throughout the day. Given that the injured athlete greatly reduces physical activity levels, maintaining muscle mass whilst simultaneously avoiding gains in fat mass can become challenging. Nevertheless, evidence suggests that maintaining or increasing daily protein intake by focusing upon the amount, type and timing of dietary protein ingestion throughout the day can restrict the loss of muscle mass and strength during recovery from injury. Moreover, neuromuscular electrical stimulation may be applied to evoke involuntary muscle contractions and support muscle mass maintenance in the injured athlete. Although more applied work is required to translate laboratory findings directly to the injured athlete, current recommendations for practitioners aiming to limit the loss of muscle mass and/or strength following injury in their athletes are outlined herein.

Drug analysis and development with PET should fully exhaust the ability of this tomographic technique to quantify regional tracer concentrations in vivo. Data evaluation based on visual inspection or assessment of regional image contrast is not sufficient for this purpose since much of the information present in dynamically acquired data is not used by these approaches. Compartment modelling of dynamic PET data is generally the method of choice since it allows a quantitative assessment of the underlying pharmacokinetic parameters describing drug transport, metabolism and molecular interactions. We present here an overview of key issues of compartment modelling with specific attention to the assumptions underlying the various models and their limitations. We believe that a thorough understanding of the applicability of models is mandatory for the development, successful execution and analysis of quantitative PET studies. Otherwise, meaningful and interpretable results will often not be obtained.

The leucine turnover in newborn infants is influenced by factors such as nutritional state and corticosteroid treatment. Little is known about maternal factors influencing the leucine turnover in the newborn. In order to approach the effect of preeclampsia in the mother on neonatal protein turnover, we studied the leucine turnover in preterm infants soon after birth and again after 7 days. Ten infants from preeclamptic mothers (birth weight 1,280 +/- 240 g, gestational age 31 +/- 2 weeks) and 15 control patients (birth weight 1,320 +/- 210 g, gestational age 30 +/- 2 weeks) were enrolled. The leucine turnover was measured using a primed constant 5-hour intravenous infusion of [1-C-13]leucine within the first 24 h after delivery and again on day 7 of life. The turnover (leucine flux; mumol(.)kg(-1.)h(-1)) was calculated from the enrichment in alpha-ketoisocaproic acid in plasma. The leucine turnover on day 1 was 300 +/- 65 in the preeclampsia group and 358 +/- 70 in the controls (ANOVA, p

Objective: To assess consolidation in amnestic mild cognitive impairment (aMCI), controlling for differences in initial learning and using a protracted delay period for recall. Method: 15 individuals with aMCI were compared with 15 healthy older adult controls on a story learning task. Subjects were trained to criteria to equalize initial learning across subjects. Recall was tested at both the 30-min typically used delay and a 1-week delay used to target consolidation. Results: Using repeated measures ANOVAs adjusted for age, we found group × time point interactions across the entire task between the final trial and 30-min delay, and again between the 30-min and 1-week delay periods, with aMCI having greater declines in recall as compared with controls. Significant group main effects were also found, with aMCI recalling less than controls. Conclusion: Consolidation was impaired in aMCI as compared with controls. Our findings indicate that aMCI-related performance typically measured at 30 min underestimates aMCI-associated memory deficits. This is the first study to isolate consolidation by controlling for initial learning differences and using a protracted delay period to target consolidation in an aMCI sample. (PsycInfo Database Record (c) 2020 APA, all rights reserved)

Angiotensin II is known to stimulate cardiac hypertrophy and contractility. Most angiotensin II effects are mediated via membrane bound AT(1) receptors. However, the role of myocardial AT(1) receptors in cardiac hypertrophy and contractility is still rarely defined. To address the hypothesis that increased myocardial AT(1) receptor density causes cardiac hypertrophy apart from high blood pressure we developed a transgenic rat model which expresses the human AT(1) receptor under the control of the alpha -myosin heavy-chain promoter specifically in the myocardium. Expression was identified and quantified by northern blot analysis and radioligand binding assays, demonstrating overexpression of angiotensin II receptors in the transgenic rats up to 46 times the amount seen in nontransgenic rats. Coupling of the human AT(1) receptor to rat G proteins and signal transduction cascade was verified by sensitivity to GTP-gamma -S and increased sensitivity of intracellular Ca2+ [Ca2+](i) to angiotensin II in fluo-3 loaded transgenic cardiomyocytes. Transgenic rats exhibited normal cardiac growth and function under baseline conditions. Pronounced hypertrophic growth and contractile responses to angiotensin II, however, were noted in transgenic rats challenged by volume and pressure overload. In summary, we generated a new transgenic rat model that exhibits an upregulated myocardial AT(1) receptor density and demonstrates augmented cardiac hypertrophy and contractile response to angiotensin II after volume and pressure overload, but not under baseline conditions.

The objective of this study was to determine whether insulin administration would prevent the well-documented catabolic effect of dexamethasone given to preterm infants with chronic lung disease. We studied leucine metabolism in 11 very-low-birth-weight infants before dexamethasone treatment and on d 2. 4. and 7 thereafter, During the first 4 d of dexamethasone. insulin was administered i.v. at a dose of 0.5 (n = 7) or 1.0 (n = 5) lU/kg/d. Leucine turnover was not significantly different between d 0 (337 +/- 41.3 mu mol leucine/kg/h). d 2 (288 +/- 27.2 mu mol leucine/kg/h), d 4 (302 +/- 22.1 mu mol leucine/kg/h), and d 7 (321 +/- 21.2 mu mol leucine/kg/h), and neither was leucine breakdown (272 +/- 21.9 mu mol leucine/kg/h on d 0, 225 +/- 21.5 mu mol leucine/kg/h on d 2, 231 +/- 21 mu mol leucine/kg/h on d 4, and 242 +/- 17.6 mu mol ieucine/kg/h on d 7). Weight gain rates were significantly tower during the first week of dexamethasone treatment compared with the week before treatment or the second and third week. We conclude that during insulin and corticosteroid administration ill very-low-birth-weight infants, no changes were observed in leucine kinetics in contrast to previous studies, The decrease in weight gain was not reversed.

The aim of the present study was to determine the rate of very-low-density lipoprotein (VLDL)-apolipoprotein (apo) B100 secretion in humans with a minimized amount of L-[1-C-13]valine infusion in combination with the use of gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) analysis. To compare this method with the conventional gas chromatography/mass spectrometry (GC/MS) technique, two different dosages of L-[1-C-13]valine and both analytical techniques were compared in a single study. A priming dose of L-[1-C-13]valine (2 mu mol/kg) followed by a constant infusion (2 mu mol/kg/h) was given for 3 h, directly followed by a second priming dose (15 mu mol/kg) and a constant infusion (15 mu mol/kg/h) for 4 h. The fractional secretion rate obtained by GC/C/IRMS measurements from the first 3 h of infusion (mean +/- SD: 0.22 +/- 0.09 pools/h) was similar to that obtained by GC/MS during the last 4 h of infusion (0.23 +/- 0.07 pools/h; P = 0.56). In conclusion, superior analytical accuracy and sensitivity of GC/C/IRMS enable measurements of VLDL-apo B100 secretion with much lower doses of L-[1-C-13]valine and allow for reduction of experimental costs. (C) 1998 Academic Press.

Proportionate increase of fibrinogen and albumin synthesis in nephrotic patients: Measurements with stable isotopes. Hyperfibrinogenemia is a common feature of the nephrotic syndrome, and contributes to increased tendency for thrombosis and atherosclerosis. Its genesis is not certain, but the increase in liver fibrinogen mRNA in nephrotic rats indicates increased synthesis. Data in humans are scarce. We presently compared synthesis rates of fibrinogen and albumin in nephrotic adults (N = 7; plasma albumin 22.3 ± 0.7 g/liter, proteinuria 12 g/day) and healthy control subjects (N = 8) using a primed/continuous infusion of the stable isotope L-[1-13C]valine for six hours. Absolute synthesis rate (ASR) of fibrinogen was 31 ± 3 mg/kg/day in nephrotic subjects and 21 ± 1 mg/kg/day in control subjects (P < 0.05), and positively correlated with plasma fibrinogen (P = 0.0317). The plasma fibrinogen pool was disproportionately increased in the nephrotic patients (271 ± 30 mg/kg) compared to the controls (126 ± 8 mg/kg), suggesting decreased fractional catabolic rate as well. The ASR of albumin was increased from 71 ± 4 mg/kg/day in the controls to 160 ± 19 mg/kg/day in the patients (P < 0.0001), and strongly correlated with the ASR of fibrinogen (P = 0.0046). Plasma α2-macroglobulin was also elevated and correlated with the albumin synthesis rate, whereas plasma serum amyloid A and C-reactive protein were not elevated. These data suggest that in nephrotic patients the increased albumin synthesis is associated with an increase in synthesis of a specific and coordinated group of proteins, among which is fibrinogen.

Hyperfibrinogenemia is a common feature of the nephrotic syndrome, and contributes to increased tendency for thrombosis and atherosclerosis. Its genesis is not certain, but the increase in liver fibrinogen mRNA in nephrotic rats indicates increased synthesis. Data in humans are scarce. We presently compared synthesis rates of fibrinogen and albumin in nephrotic adults (N = 7; plasma albumin 22.3 +/- 0.7 g/liter, proteinuria 12 g/day) and healthy control subjects (N = 8) using a primed/continuous infusion of the stable isotope L-[1-C-13]valine for six hours. Absolute synthesis rate (ASR) of fibrinogen was 31 +/- 3 mg/kg/day in nephrotic subjects and 21 +/- 1 mg/kg/day in control subjects (P

AIM: Short periods of muscle disuse, due to illness or injury, result in substantial skeletal muscle atrophy. Recently, we have shown that a single session of neuromuscular electrical stimulation (NMES) increases muscle protein synthesis rates. The aim was to investigate the capacity for daily NMES to attenuate muscle atrophy during short-term muscle disuse. METHODS: Twenty-four healthy, young (23 +/- 1 year) males participated in the present study. Volunteers were subjected to 5 days of one-legged knee immobilization with (NMES; n = 12) or without (CON; n = 12) supervised NMES sessions (40-min sessions, twice daily). Two days prior to and immediately after the immobilization period, CT scans and single-leg one-repetition maximum (1RM) strength tests were performed to assess quadriceps muscle cross-sectional area (CSA) and leg muscle strength respectively. Furthermore, muscle biopsies were taken to assess muscle fibre CSA, satellite cell content and mRNA and protein expression of selected genes. RESULTS: In CON, immobilization reduced quadriceps CSA by 3.5 +/- 0.5% (P < 0.0001) and muscle strength by 9 +/- 2% (P < 0.05). In contrast, no significant muscle loss was detected following immobilization in NMES although strength declined by 7 +/- 3% (P < 0.05). Muscle MAFbx and MuRF1 mRNA expression increased following immobilization in CON (P < 0.001 and P = 0.07 respectively), whereas levels either declined (P < 0.01) or did not change in NMES, respectively. Immobilization led to an increase in muscle myostatin mRNA expression in CON (P < 0.05), but remained unchanged in NMES. CONCLUSION: During short-term disuse, NMES represents an effective interventional strategy to prevent the loss of muscle mass, but it does not allow preservation of muscle strength. NMES during disuse may be of important clinical relevance in both health and disease.

Exercise has been shown to reduce age-related losses in cognitive function including learning and memory, but the mechanisms underlying this effect remain poorly understood. Memory formation occurs in stages that include an initial acquisition phase, an intermediate labile phase, and then a process of consolidation which leads to long term memory formation. An effective way to examine the mechanism by which exercise improves memory is to introduce the intervention (exercise), post-acquisition, making it possible to selectively examine memory storage and consolidation. Accordingly we evaluated the effects of post-trial exercise (10 minutes on a treadmill) on memory consolidation in aged canines both right after, an hour after, and twenty-four hours after acute exercise training in concurrent discrimination, object location memory (OLM) and novel object recognition (NOR) tasks. Our study shows that post-trial exercise facilitates memory function by improving memory consolidation in aged animals in a time-dependent manner. The improvements were significant at twenty-four hour post exercise and not right after or one hour after exercise. Aged animals were also tested following chronic exercise (10 min/day for 14 consecutive days) on OLM or till criterion were reached (for reversal learning task). We found improvements from a chronic exercise design in both the object location and reversal learning tasks. Our studies suggest that mechanisms to improve overall consolidation and cognitive function remain accessible even with progressing age and can be re-engaged by both acute and chronic exercise.

Indigenous heterotrophic marine bacteria are of great importance to global nutrient cycling. Predominant native bacteria are of ultramicrobacterial dimensions, are not associated with aggregates and must have truly remarkable abilities for substrate capture. Agar media are unsuited for the isolation of the dominant oceanic bacterioplankton. In contrast, the dilution culture technique [Button et al. (1993) Appl. Environ. Microbiol. 59, 881-891; Schut et al. (1993) Appl. Environ. Microbiol. 59, 2150-2160] leads to a successful enrichment of the dominant cell types. Up to 50% of the indigenous bacterial population in water obtained from Resurrection Bay was able to grow in dilution tubes containing only filtered, autoclaved natural sea water (FAS). Ultramicrobacteria (UMB), very small bacteria with small genomes, predominate in such cultures. Generally, dilution factors that resulted in inocula of approximately 2 cells per tube were optimal and prevented outgrowth of atypical large bacteria. Strain RB2256 [Schut et al. (1993) Appl. Environ. Microbiol. 59, 2150-2160], one of the UMB isolated by this dilution culture technique and tentatively identified as a marine Sphingomonas sp., was investigated in more detail. Although reverted from obligately oligotrophic to facultatively oligotrophic upon isolation, this strain possessed a number of traits assigned to a 'model oligotroph' and some unpredicted novel properties. The cells showed no miniaturisation upon starvation but consistently exhibited low cell volumes. They had a very low DNA content, were rich in protein, and contained only one copy of the rRNA operon. The cells were well adapted to the simultaneous utilisation of mixed substrates. A constitutive, high-affinity and binding protein-dependent uptake system for mixed amino acids was found that would allow realistic in situ generation times at the prevailing amino acid concentrations. Further studies on this same organism revealed that the cells appeared to be extremely resistant to various stress-inducing agents. High survival rates were observed after high-intensity heat shocks, treatments with H2O2 or with ethanol. Moreover, no marked differences were observed between starved or actively growing cells in this respect, particularly when cells were grown in chemostat. Application of the dilution culture technique to the field of subsurface microbiology could be adopted to study the occurrence of UMB in groundwater with a comparable and stable 'low-nutrient-conditioned' phenotype.

The aerobic degradation of phytoplankton debris collected in Dutch coastal waters on 2 days in 1991 (15 April and 8 May), representing 2 physiological stages of a phytoplankton spring bloom dominated by Phaeocystis sp., was studied in batch culture experiments. The bacterial production and the concentrations of particulate organic carbon (POC) and dissolved organic carbon (DOG) were monitored over a period of 102 d. Bacterial numbers and biomass were followed for 35 d. All experiments showed a rapid metabolic response of bacteria and a sharp decrease in the concentration of POC and DOC during the first days of the experiments. Thereafter bacterial production rates remained constant, and POC and DOC decreased slowly. Apparently, the phytoplankton debris consisted of a labile, rapidly degradable fraction and a refractory, slowly degradable fraction. The labile fraction comprised approximately 50 % of the debris, and was degraded with a bacterial carbon conversion efficiency of between 10 and 20%. There were no indications that antibiotic compounds present in the algal debris inhibited the degradation. Acrylate, a proposed antibiotic compound which was present in the algal debris, was rapidly degraded in a control experiment. The percentage of the material that had been degraded after 102 d was highest in the experiment with material collected in May. It was concluded that during the early phase of the bloom, more refractory compounds are produced.

Protein synthesis is a template polymerization process composed by three main steps: initiation, elongation, and termination. During translation, ribosomes are engaged into polysomes whose size is used for the quantitative characterization of translatome. However, simultaneous transcription and translation in the bacterial cytosol complicates the analysis of translatome data. We established a procedure for robust estimation of the ribosomal density in hundreds of genes from Lactococcus lactis polysome size measurements. We used a mechanistic model of translation to integrate the information about the ribosomal density and for the first time we estimated the protein synthesis rate for each gene and identified the rate limiting steps. Contrary to conventional considerations, we find significant number of genes to be elongation limited. This number increases during stress conditions compared to optimal growth and proteins synthesized at maximum rate are predominantly elongation limited. Consistent with bacterial physiology, we found proteins with similar rate and control characteristics belonging to the same functional categories. Under stress conditions, we found that synthesis rate of regulatory proteins is becoming comparable to proteins favored under optimal growth. These findings suggest that the coupling of metabolic states and protein synthesis is more important than previously thought., Author Summary Post-transcriptional regulation is important for the understanding of gene expression control. Our work is a genome-scale analysis of the translation steps of protein synthesis from transcripts. We have developed a mathematical model to integrate and analyze experimental ribosome density of hundreds of transcripts of Lactococcus lactis, providing robust estimation of polysome sizes. Using a mechanistic approach we have modeled for the first time in bacteria the protein synthesis rate for each gene and determined by control analysis the limiting rate between initiation, elongation and termination. Highly expressed proteins belonged to the group of the proteins with high synthesis rate and were controlled by elongation. Unexpectedly, a significant number of genes under elongation limitation were found although initiation was generally believed to be limiting. In addition, we showed that translation rate and control were in agreement with cellular requirements in cells growing in optimal environment but also in cells under nutritional limitation. This work provided a better understanding of translational regulation in bacteria and demonstrated how protein synthesis control was closely related to cellular metabolic states.

Situations such as the recovery from injury and illness can lead to enforced periods of muscle disuse or unloading. Such circumstances lead to rapid skeletal muscle atrophy, loss of functional strength and a multitude of related negative health consequences. The elderly population is particularly vulnerable to the acute challenges of muscle disuse atrophy. Any loss of skeletal muscle mass must be underpinned by a chronic imbalance between muscle protein synthesis and breakdown rates. It is recognized that muscle atrophy during prolonged ( > 10 days ) disuse is brought about primarily by declines in post-absorptive and post-prandial muscle protein synthesis rates, without a clear contribution from changes in muscle protein breakdown. Few data are available on the impact of short-term disuse ( < 10 days ) on muscle protein turnover in humans. However, indirect evidence indicates that considerable muscle atrophy occurs during this early phase, and is likely attributed to a rapid increase in muscle protein breakdown accompanied by the characteristic decline in muscle protein synthesis. Short-term disuse atrophy is of particular relevance in the development of sarcopenia, as it has been suggested that successive short periods of muscle disuse, due to sickness or injury, accumulate throughout an individual's lifespan and contributes considerably to the net muscle loss observed with aging. Research is warranted to elucidate the physiological and molecular basis for rapid muscle loss during short periods of disuse. Such mechanistic insight will allow the characterization of nutritional, exercise and/or pharmacological interventions to prevent or attenuate muscle loss during periods of disuse and therefore aid in the treatment of age-related sarcopenia.

AIM: The impact of disuse on the loss of skeletal muscle mass and strength has been well documented. Given that most studies have investigated muscle atrophy after more than 2 weeks of disuse, few data are available on the impact of shorter periods of disuse. We assessed the impact of 5 and 14 days of disuse on skeletal muscle mass, strength and associated intramuscular molecular signaling responses. METHODS: Twenty-four healthy, young (23+/-1 y) males were subjected to either 5 (n=12) or 14 (n=12) days of one-legged knee immobilization using a full leg cast. Before and immediately after the immobilization period, quadriceps muscle cross-sectional area (CSA), leg lean mass and muscle strength were assessed, and biopsies were collected from the vastus lateralis. RESULTS: Quadriceps muscle CSA declined from baseline by 3.5+/-0.5 (P

International audience; RNA maturation is a key event regulating genes at post-transcriptional level. In bacteria, it is employed to adjust the amounts of proteins and functional RNAs, often in response to environmental constraints. During the process of RNA maturation, enzymes and factors that would otherwise promote RNA degradation convert a labile RNA into a stable and biologically functional molecule.

Decades of research have resulted in a remarkably detailed understanding of the molecular mechanisms of bacterial DNA replication, transcription and translation. Our understanding of the kinetics and physical mechanisms that drive these processes forward has been expanded by the ability of single-molecule in vitro techniques, such as force spectroscopy and single-molecule Forster (fluorescence) resonance energy transfer (smFRET), to capture short-lived intermediate states in complex pathways. Furthermore, these technologies have revealed novel mechanisms that support enzyme processivity and govern the assembly of large multicomponent complexes. Here, we summarize the application of in vitro single-molecule studies to the analysis of fundamental bacterial processes, with a focus on the most recent functional insights that have been gained from fluorescence-based methods.

One of our most intriguing mental abilities is the capacity to store information and recall it from memory. Computational neuroscience has been influential in developing models and concepts of learning and memory. In this tutorial review we focus on the interplay between learning and forgetting. We discuss recent advances in the computational description of the learning and forgetting processes on synaptic, neuronal, and systems levels, as well as recent data that open up new challenges for statistical physicists.

Benthic oxygen uptake, sulphate reduction and benthic bacterial production were measured at two contrasting locations in the southern North Sea: the shallow and turbulent Broad Fourteens area in the Southern Eight, and the deeper Oyster Grounds, a deposition area, where thermohaline stratification occurs during summer, Oxygen uptake and sulphate reduction showed a clear seasonal pattern in the Broad Fourteens area, indicating a supply of carbon to the benthic system that is closely related to the standing stock of carbon in the water column. This close benthic-pelagic coupling is probably due to the influence of the tide in this part of the North Sea, which keeps the water column permanently mixed, At the Oyster Grounds, no seasonal pattern was observed. Peaks in oxygen uptake and sulphate reduction were found in winter, Irregularly occurring events, such as storms and fishery-related activities, are likely to affect the benthic mineralization patterns in this area, Annual benthic carbon mineralization rates estimated from oxygen uptake rates were 44 gC . m(-2) at the Broad Fourteens, and 131 gC . m(-2) at the Oyster Grounds, of which 26 and 28%, respectively, could be attributed to sulphate reduction (assuming an annual sulphide reoxidation rate of 100%). Although sulphate reduction rates in the southern North Sea are higher than previously suggested, aerobic respiration is the most important pathway for benthic carbon mineralization at the stations visited, Production rates of benthic bacterial carbon measured with labelled leucine were much higher than carbon mineralization rates based on oxygen uptake or sulphate reduction. This may either imply a very high bacterial carbon conversion efficiency, or point to shortcomings in the accuracy of the techniques. A critical evaluation of the techniques is recommended.

Benthic oxygen uptake, sulphate reduction and benthic bacterial production were measured at two contrasting locations in the southern North Sea: the shallow and turbulent Broad Fourteens area in the Southern Eight, and the deeper Oyster Grounds, a deposition area, where thermohaline stratification occurs during summer, Oxygen uptake and sulphate reduction showed a clear seasonal pattern in the Broad Fourteens area, indicating a supply of carbon to the benthic system that is closely related to the standing stock of carbon in the water column. This close benthic-pelagic coupling is probably due to the influence of the tide in this part of the North Sea, which keeps the water column permanently mixed, At the Oyster Grounds, no seasonal pattern was observed. Peaks in oxygen uptake and sulphate reduction were found in winter, Irregularly occurring events, such as storms and fishery-related activities, are likely to affect the benthic mineralization patterns in this area, Annual benthic carbon mineralization rates estimated from oxygen uptake rates were 44 gC . m(-2) at the Broad Fourteens, and 131 gC . m(-2) at the Oyster Grounds, of which 26 and 28%, respectively, could be attributed to sulphate reduction (assuming an annual sulphide reoxidation rate of 100%). Although sulphate reduction rates in the southern North Sea are higher than previously suggested, aerobic respiration is the most important pathway for benthic carbon mineralization at the stations visited, Production rates of benthic bacterial carbon measured with labelled leucine were much higher than carbon mineralization rates based on oxygen uptake or sulphate reduction. This may either imply a very high bacterial carbon conversion efficiency, or point to shortcomings in the accuracy of the techniques. A critical evaluation of the techniques is recommended.

ACE inhibitors effectively reduce systemic vascular resistance in patients with hypertension, heart failure or chronic renal disease. This antihypertensive efficacy probably accounts for an important part of their long term renoprotective effects in patients with diabetic and non-diabetic renal disease.The renal mechanisms underlying the renal adverse effects of ACE inhibitors - intrarenal efferent vasodilation with a consequent fall in filtration pressure - are held to be involved in their renoprotective effects as well. The fall in filtration pressure presumably contributes to the antiproteinuric effect as well as to long term renoprotection. The former is suggested by the positive correlation between the fall in filtration fraction and the reduction in proteinuria found during ACE inhibition. The latter is suggested by the correlation between the (slight) reduction in glomerular filtration rate at onset of therapy and a more favourable course of renal function in the long term. Such a fall in filtration rate at the onset of ACE inhibitor treatment is reversible after withdrawal, and can be considered the trade-off for long term renal protection in patients with diabetic and nondiabetic chronic renal disease.In conditions in which glomerular filtration is critically dependent on angiotensin II-mediated efferent vascular tone (such as a post-stenotic kidney, or patients with heart failure and severe depletion of circulating volume), ACE inhibition can induce acute renal failure, which is reversible after withdrawal of the drug.Systemic and renal haemodynamic effects of ACE inhibition, both beneficial and adverse, are potentiated by sodium depletion. Consequently, sodium repletion contributes to the restoration of renal function in patients with ACE inhibitor-induced acute renal failure. On the other hand, co-treatment with diuretics and sodium restriction can improve therapeutic efficacy in patients in whom the therapeutic response of blood pressure or proteinuria is insufficient.Patients at the greatest risk for renal adverse effects (those with heart failure, diabetes mellitus and/or chronic renal failure) also can expect the greatest benefit. Therefore, ACE inhibitors should not be withheld in these patients, but dosages should be carefully titrated, with monitoring of renal function and serum potassium levels.

BACKGROUND: Fibrous ingredients for pig diets can be characterized by in vitro fermentation. In vitro fermentation methods often use a one-time measurement of gas production during the incubation of test substrates with one faecal inoculum. The representativeness of this approach can be questioned as measuring time and number of animals from which inoculum originates may influence fermentation results. An in vitro fermentation trial was conducted incubating three fibrous substrates with three inocula in five replicates (different fermentation runs) to test the influence of run and origin of inocula. RESULTS: Total gas production and maximal rate of gas production differed (P

The eukaryotic initiation factor 3 subunit f (eIF3f) is one of the 13 subunits of the translation initiation factor complex eIF3 required for several steps in the initiation of mRNA translation. In skeletal muscle, recent studies have demonstrated that eIF3f plays a central role in skeletal muscle size maintenance. Accordingly, eIF3f overexpression results in hypertrophy through modulation of protein synthesis via the mTORC1 pathway. Importantly, eIF3f Was described as a target of the E3 ubiquitin ligase MAFbx/atrogin-1 for proteasome-mediated breakdown under atrophic conditions. The biological importance of the MAFbx/atrogin-1-dependent targeting of eFI3f is highlighted by the finding that expression of ad eIF3f mutant insensitive to MAFbx/atrogin-1 polyubiquitination is associated with enhanced protection against starvation-induced muscle atrophy. A better understanding of the precise role of this subunit should lead to the development of new therapeutic approaches to prevent or limit muscle wasting that prevails in numerous physiological and pathological states such as immobilization, aging, denervated conditions, neuromuscular diseases, AIDS, cancer, diabetes. This article is part of a Directed Issue entitled: Molecular basis of muscle wasting. (C) 2013 Elsevier Ltd. All rights reserved.

International audience; The regulation of the protein synthesis has a crucial role in governing the eukaryotic cell growth. Subtle changes of proteins involved in the translation process may alter the rate of the protein synthesis and modify the cell fate by shifting the balance from normal status into a tumoral or apoptotic one. The largest eukaryotic initiation factor involved in translation regulation is eIF3. Amongst the 13 factors constituting eIF3, the f subunit finely regulates this balance in a cell-type-specific manner. Loss of this factor causes malignancy in several cells, and atrophy in normal muscle cells. The intracellular interacting partners which influence its physiological significance in both cancer and muscle cells are detailed in this review. By delineating the global interaction network of this factor and by clarifying its intracellular role, it becomes apparent that the f subunit represents a promising candidate molecule to use for biotherapeutic applications.

Cancer initiation and progression involve microRNAs that can function like tumor suppressors and oncogenes. The functional significance of most miRNAs is currently unknown. To determine systematically which microRNAs are essential for glioma growth, we screened a precursor microRNA library in three human glioblastoma and one astroglial cell line model systems. The most prominent and consistent cell proliferation–reducing hits were validated in secondary screening with an additional apoptosis endpoint. The functional screening data were integrated in the miRNA expression data to find underexpressed true functional tumor suppressor miRNAs. In addition, we used miRNA-target gene predictions and combined siRNA functional screening data to find the most probable miRNA-target gene pairs with a similar functional effect on proliferation. Nine novel functional miRNAs (hsa-miR-129, -136, -145, -155, -181b, -342-5p, -342-3p, -376a/b) in GBM cell lines were validated for their importance in glioma cell growth, and similar effects for six target genes (ROCK1, RHOA, MET, CSF1R, EIF2AK1, FGF7) of these miRNAs were shown functionally. The clinical significance of the functional hits was validated in miRNA expression data from the TCGA glioblastoma multiforme (GBM) tumor cohort. Five tumor suppressor miRNAs (hsa-miR-136, -145, -342, -129, -376a) showed significant underexpression in clinical GBM tumor samples from the TCGA GBM cohort further supporting the role of these miRNAs in vivo. Most importantly, higher hsa-miR-145 expression in GBM tumors yielded significantly better survival (p

We are grateful to Florence Blandel for carbonylated protein analysis. We would like to thank Morgane Le-Gall, Guilhem Clary, and Cedric Broussard for their help in the DIGE experiments and MS analysis. We also thank Professor E. Fontaine for helpful discussion.; Citrulline (Cit) actions on muscle metabolism remain unclear. Those latter were investigated using a proteomic approach on Tibialis muscles from male Sprague-Dawley rats. At 23 months of age, rats were either fed ad libitum (AL group) or subjected to dietary restriction for 12 weeks. At the end of the restriction period, one group of rats was euthanized (R group) and two groups were refed for one week with a standard diet supplemented with nonessential amino acids group or Cit (CIT group). Results of the proteomic approach were validated using targeted Western blot analysis and assessment of gene expression of the related genes. Maximal activities of the key enzymes involved in mitochondrial functioning were also determined. Cit supplementation results in a significant increase in the protein expression of the main myofibrillar constituents and of a few enzymes involved in glycogenolysis and glycolysis (CIT vs. AL and R, p < 0.05). Conversely, the expression of oxidative enzymes from Krebs cycle and mitochondrial respiratory chain was significantly decreased (CIT vs. AL, p < 0.05). However, maximal activities of key enzymes of mitochondrial metabolism were not significantly affected, except for complex 1 which presented an increased activity (CIT vs. AL and R, p < 0.05). In conclusion, Cit supplementation increases expression of the main myofibrillar proteins and seems to induce a switch in muscle energy metabolism, from aerobia toward anaerobia.

We report on a new maternally-inherited syndrome characterized by a combination of sensorineural hearing loss, ataxia and myoclonus in a large kindred from Sicily, Hearing loss was the most widespread and sometimes the only symptom found in family members. Sequence analysis of the mitochondrial DNA regions encompassing the tRNA genes revealed the presence of a heteroplasmic insertion at nucleotide position 7472. The insertion adds a seventh cytosine to a six-cytosine run that is part of the mitochondrial tRNA(Ser(UCN)) gene, Conformational analysis showed that this mutation is likely to alter the structure of the T Psi C loop in the tRNA(Ser(UCN)) clover leaf secondary structure, Moreover, the degree of heteroplasmy in blood and muscle was correlated with the clinical phenotype, and homoplasmic mutant cybrids showed decreased complex I activity, low oxygen consumption and high lactic acid output, indicating faulty oxidative phosphorylation, Finally, mutation was absent in 381 unrelated maternal lineages, suggesting specific segregation with the disease. We propose that the C7472 insertion-mutation is pathogenic, and etiologically related to hearing loss and other symptoms that define a novel maternally-inherited clinical entity.

1. The aim of this study was to find a drug that induces an almost complete degranulation of secretory cells in rat parotid and submandibular glands. 2. Phenylephrine (alpha-adrenergic), isoproterenol (beta-adrenergic) and mecholine (muscarinic cholinergic) were tested. Time and degree of maximal depletion of acinar and granular convoluted tubule cells were determined morphologically. 3. Following phenylephrine-injection (5 mg/kg or 10.2 mg/kg, i.p.), no effect on the acinar granulation level was observed in either of the glands, while about 50-60% granular convoluted tubules were degranulated for at least 120-180 min postinjection. 4. With isoproterenol (5, 10, 40, 70 or 100 mg/kg, i.p.), degranulation of 100% of the acinar cells in the parotid and 80% of the acinar cells in the submandibular gland was observed 90 min post-injection. Granular convoluted tubule cells did not respond to this beta-adrenergic drug. 5. Mecholine (3.75 or 7.5 mg/kg, i.p.) induced mainly degranulation of granular convoluted tubule cells (about 50% after 120 min). Numbers of granulated acinar cells decreased only slightly in both glands (about 10%, 90-120 min). 6. From this study it appears that with a relatively low dosage (5 mg/kg, i.p.) of isoproterenol, a high level of degranulation can be induced in acinar cells of rat parotid and submandibular glands without toxic side effects. Concerning granular convoluted tubules, only moderate degranulation was observed with phenylephrine and mecholine, respectively.

We thank Mai Persson, Charles Ford, Jaime Gransee, and Melissa Aakre for technical expertise. We are grateful to Drs. Ethan Anderson and Darryl Neufer for guidance on H2O2 production measurements; Caloric restriction (CR) mitigates many detrimental effects of aging and prolongs life span. CR has been suggested to increase mitochondrial biogenesis, thereby attenuating age-related declines in mitochondrial function, a concept that is challenged by recent studies. Here we show that lifelong CR in mice prevents age-related loss of mitochondrial oxidative capacity and efficiency, measured in isolated mitochondria and permeabilized muscle fibers. We find that these beneficial effects of CR occur without increasing mitochondrial abundance. Whole-genome expression profiling and large-scale proteomic surveys revealed expression patterns inconsistent with increased mitochondrial biogenesis, which is further supported by lower mitochondrial protein synthesis with CR. We find that CR decreases oxidant emission, increases antioxidant scavenging, and minimizes oxidative damage to DNA and protein. These results demonstrate that CR preserves mitochondrial function by protecting the integrity and function of existing cellular components rather than by increasing mitochondrial biogenesis.

Bu çalışma, 12-15 Mayıs 2005 tarihleri arasında Tirana[Arnavutluk]’da düzenlenen 5. Balkan Symposium on Vegetables and Potatoes’da bildiri olarak sunulmuştur. In this study, hydration (priming with PEG 8000 and humidification) treatments were carried out in seeds of onion cultivars 'Akgun-12', 'Valencia', 'TEG-502' and 'Contes' (having approximately 80% viability) in order to investigate their effects on germination rate, mean germination time (MGT), total lipid, total protein, soluble protein and malondialdehyde (MDA) contents and catalase activity. Priming treatments increased germination rate in cultivars 'Akgun-12' and 'Contes', however, no significant effect was observed in cultivars 'Valencia' and 'TEG-502'. Priming treatments shortened MGT in cultivars 'Akgun-12' and 'Contes', nevertheless, prolonged in cultivar 'TEG-502'. Moreover, no significant change was observed in cultivar 'Valencia'. Humidification treatments increased germination rate and shortened MGT in all the cultivars. While priming treatments had no significant effect on total lipid and protein rates in all the cultivars, humidification treatments reduced total lipid rate but increased total protein rate. Hydration treatments did not have any significant effect on soluble protein content in seeds of all the onion cultivars. Following hydration treatments, MDA content decreased in cultivars 'TEG-502' and 'Contes', however, there was no significant effect in cultivars 'Akgun-12' and 'Valencia'. Furthermore, hydration treatments increased catalase activity in all the cultivars. On the other hand, humidification treatments increased catalase activity more than priming treatments. Consequently, instead of priming, humidification technique is recommended for onion seeds as a general practice in gene banks and seed companies, since it is a more economical treatment in terms of time and expenses and its ease of use. Int Soc Hort Sci (ISHS)

Placental vascular formation and blood flow are crucial for fetal survival, growth and development, and arginine regulates vascular development and function. This study determined the effects of dietary arginine or N-carbamylglutamate (NCG) supplementation during late gestation of sows on the microRNAs, vascular endothelial growth factor A (VEGFA) and endothelial nitric oxide synthase (eNOS) expression in umbilical vein. Twenty-seven landrace × large white sows at day (d) 90 of gestation were assigned randomly to three groups and fed the following diets: a control diet and the control diet supplemented with 1.0% l-arginine or 0.10% NCG. Umbilical vein of fetuses with body weight around 2.0 kg (oversized), 1.5 kg (normal) and 0.6 kg (intrauterine growth restriction, IUGR) were obtained immediately after farrowing for miR-15b, miR-16, miR-221, miR-222, VEGFA and eNOS real-time PCR analysis. Compared with the control diets, dietary Arg or NCG supplementation enhanced the reproductive performance of sows, significantly increased (P

Diurnal cycles provide a tractable system to study the response of metabolism and growth to fluctuating temperatures. We reasoned that the response to daytime and night temperature may vary; while daytime temperature affects photosynthesis, night temperature affects use of carbon that was accumulated in the light. Three Arabidopsis thaliana accessions were grown in thermocycles under carbon-limiting conditions with different daytime or night temperatures (12 to 24 degrees C) and analyzed for biomass, photosynthesis, respiration, enzyme activities, protein levels, and metabolite levels. The data were used to model carbon allocation and growth rates in the light and dark. Low daytime temperature led to an inhibition of photosynthesis and an even larger inhibition of growth. The inhibition of photosynthesis was partly ameliorated by a general increase in protein content. Low night temperature had no effect on protein content, starch turnover, or growth. In a warm night, there is excess capacity for carbon use. We propose that use of this capacity is restricted by feedback inhibition, which is relaxed at lower night temperature, thus buffering growth against fluctuations in night temperature. As examples, the rate of starch degradation is completely temperature compensated against even sudden changes in temperature, and polysome loading increases when the night temperature is decreased.

International audience; Skeletal muscle loss is observed in several physiopathological situations. Strategies to prevent, slow down, or increase recovery of muscle have already been tested. Besides exercise, nutrition, and more particularly protein nutrition based on increased amino acid, leucine or the quality of protein intake has generated positive acute postprandial effect on muscle protein anabolism. However, on the long term, these nutritional strategies have often failed in improving muscle mass even if given for long periods of time in both humans and rodent models. Muscle mass loss situations have been often correlated to a resistance of muscle protein anabolism to food intake which may be explained by an increase of the anabolic threshold toward the stimulatory effect of amino acids. In this paper, we will emphasize how this anabolic resistance may affect the intensity and the duration of the muscle anabolic response at the postprandial state and how it may explain the negative results obtained on the long term in the prevention of muscle mass. Sarcopenia, the muscle mass loss observed during aging, has been chosen to illustrate this concept but it may be kept in mind that it could be extended to any other catabolic states or recovery situations.

Regular physical activity positively influences whole body energy metabolism and substrate handling in exercising muscle. While it is recognized that the effects of exercise extend beyond exercising muscle, it is unclear to what extent exercise impacts non-exercising muscles. Here we investigated the effects of an acute endurance exercise bouts on gene expression in exercising and non-exercising human muscle. To that end, 12 male subjects aged 44-56 performed one hour of one-legged cycling at 50% W(max). Muscle biopsies were taken from the exercising and non-exercising leg before and immediately after exercise and analyzed by microarray. One-legged cycling raised plasma lactate, free fatty acids, cortisol, noradrenalin, and adrenalin levels. Surprisingly, acute endurance exercise not only caused pronounced gene expression changes in exercising muscle but also in non-exercising muscle. In the exercising leg the three most highly induced genes were all part of the NR4A family. Remarkably, many genes induced in non-exercising muscle were PPAR targets or related to PPAR signalling, including PDK4, ANGPTL4 and SLC22A5. Pathway analysis confirmed this finding. In conclusion, our data indicate that acute endurance exercise elicits pronounced changes in gene expression in non-exercising muscle, which are likely mediated by changes in circulating factors such as free fatty acids. The study points to a major influence of exercise beyond the contracting muscle.

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Objective: We aimed to evaluate the effects of resistance exercise (RE) and leucine (LEU) supplementation on dexamethasone (DEXA)-induced muscle atrophy and insulin resistance.Methods: Male Wistar rats were randomly divided into DEXA(DEX), DEXA + RE (DEX-RE), DEXA + LEU (DEX-LEU), and DEXA + RE + LEU (DEX-RE-LEU) groups. Each group received DEXA 5 mg . kg(-1) . d(-1) for 7 d from drinking water and were pair-fed to the DEX group; LEU-supplemented groups received 0.135 g . kg(-1) . d(-1) through gavage for 7 d; the RE protocol was based on three sessions of squat-type exercise composed by three sets of 10 repetitions at 70% of maximal voluntary strength capacity.Results: the plantaris mass was significantly greater in both trained groups compared with the non-trained groups. Muscle cross-sectional area and fiber areas did not differ between groups. Both trained groups displayed significant increases in the number of intermediated fibers (IIa/IIx), a decreased number of fast-twitch fibers (IIb), an increased ratio of the proteins phospho(Ser2448)/ total mammalian target of rapamycin and phospho(Thr389)/total 70-kDa ribosomal protein S6 kinase. and a decreased ratio of phospho(Ser253)/total Forkhead box protein-3a. Plasma glucose was significantly increased in the DEX-LEU group compared with the DEX group and RE significantly decreased hyperglycemia. the DEX-LEU group displayed decreased glucose transporter-4 translocation compared with the DEX group and RE restored this response. LEU supplementation worsened insulin sensitivity and did not attenuate muscle wasting in rats treated with DEXA. Conversely, RE modulated glucose homeostasis and fiber type transition in the plantaris muscle.Conclusion: Resistance exercise but not LEU supplementation promoted fiber type transition and improved glucose homeostasis in DEXA-treated rats. (C) 2012 Elsevier Inc. All rights reserved. Univ São Paulo, Lab Appl Nutr & Metab, Sch Phys Educ & Sports, São Paulo, Brazil Univ São Paulo, Inst Biomed Sci, São Paulo, Brazil Univ São Paulo, Lab Mol & Cellular Physiol Exercise, Sch Phys Educ & Sports, São Paulo, Brazil Univ São Paulo, Sch Med, Lab Expt Hypertens, São Paulo, Brazil Universidade Federal de São Paulo, Dept Biosci, São Paulo, Brazil Clermont Univ, UFR Med, UMR Nutr Humaine 1019, Clermont Ferrand, France INRA, UMR Unite Nutr Humaine 1019, F-63122 St Genes Champanelle, France Universidade Federal de São Paulo, Dept Biosci, São Paulo, Brazil FAPESP: 08/51090-1 FAPESP: 10/07062-3 FAPESP: 10/10852-6 FAPESP: 11/04690-6 Web of Science

Dexamethasone (DEXA) is a potent immunosupressant and anti-inflammatory agent whose main side effects are muscle atrophy and insulin resistance in skeletal muscles. In this context, leucine supplementation may represent a way to limit the DEXA side effects. In this study, we have investigated the effects of a low and a high dose of leucine supplementation (via a bolus) on glucose homeostasis, muscle mass and muscle strength in energy-restricted and DEXA-treated rats. Since the leucine response may also be linked to the administration of this amino acid, we performed a second set of experiments with leucine given in bolus (via gavage) versus leucine given via drinking water. Leucine supplementation was found to produce positive effects (e. g., reduced insulin levels) only when administrated in low dosage, both via the bolus or via drinking water. However, under DEXA treatment, leucine administration was found to significantly influence this response, since leucine supplementation via drinking water clearly induced a diabetic state, whereas the same effect was not observed when supplied via the gavage.

It is unknown what feeding strategy to use during chemotherapy-induced gastrointestinal mucositis, which causes weight loss and possibly malabsorption. To study the absorptive capacity of amino acids during mucositis, we determined the plasma availability of enterally administered amino acids (AA), their utilization for protein synthesis, and the preferential side of the intestine for AA uptake in rats with and without methotrexate (MTX)-induced mucositis. Four days after injection with MTX (60 mg/kg) or saline (controls), rats received a primed, continuous dual-isotope infusion (intraduodenal and intravenous) of labeled L-leucine, L-lysine, L-phenylalanine, L-threonine, and L-methionine. We collected blood samples, assessed jejunal histology, and determined labeled AA incorporation in proximal and distal small intestinal mucosa, plasma albumin, liver, and thigh muscle. MTX-induced mucositis was confirmed by histology. The median systemic availability of all AA except for leucine was similar in MTX-treated rats and in controls. However, the individual availability of all AA differed substantially within the group of MTX-treated rats, ranging from severely reduced ( 40% of intake in 5 of 9 rats). More AA originating from basolateral uptake than those originating from apical uptake were used for intestinal protein synthesis in MTX-treated rats (>= 420% more, P