Exercise training-induced PPARβ increases PGC-1α protein stability and improves insulin-induced glucose uptake in rodent muscles

This study aimed to investigate the long-term effects of training intervention and resting on protein expression and stability of peroxisome proliferator-activated receptor β/δ (PPARβ), peroxisome proliferator-activated receptor gamma coactivator 1-α (PGC1α), glucose transporter type 4 (GLUT4), and mitochondrial proteins, and determine whether glucose homeostasis can be regulated through stable expression of these proteins after training. Rats swam daily for 3, 6, 9, 14, or 28 days, and then allowed to rest for 5 days post-training. Protein and mRNA levels were measured in the skeletal muscles of these rats. PPARβ was overexpressed and knocked down in myotubes in the skeletal muscle to investigate the effects of swimming training on various signaling cascades of PGC-1α transcription, insulin signaling, and glucose uptake. Exercise training (Ext) upregulated PPARβ, PGC-1α, GLUT4, and mitochondrial enzymes, including NADH-ubiquinone oxidoreductase (NUO), cytochrome c oxidase subunit I (COX1), citrate synthase (CS), and cytochrome c (Cyto C) in a time-dependent manner and promoted the protein stability of PPARβ, PGC-1α, GLUT4, NUO, CS, and Cyto C, such that they were significantly upregulated 5 days after training cessation. PPARβ overexpression increased the PGC-1α protein levels post-translation and improved insulin-induced signaling responsiveness and glucose uptake. The present results indicate that Ext promotes the protein stability of key mitochondria enzymes GLUT4, PGC-1α, and PPARβ even after Ext cessation

Order in a Spatially Anisotropic Triangular Antiferromagnet

The phase diagram of the spin-1/2 Heisenberg antiferromagnet on an anisotropic triangular lattice of weakly coupled chains, a model relevant to Cs2CuCl4, is investigated using a renormalization group analysis, which includes marginal couplings important for connecting to numerical studies of this model. In particular, the relative stability of incommensurate spiral spin-density order and collinear antiferromagnetic order is studied. While incommensurate spiral order is found to exist over most of the phase diagram in the presence of a Dzyaloshinskii-Moriya (DM) interaction, at small interchain and extremely weak DM couplings, collinear antiferromagnetic order can survive. Our results imply that Cs2CuCl4 is well within the part of the phase diagram where spiral order is stable. The implications of the renormalization group analysis for numerical studies, many of which have found spin-liquidlike behavior, are discussed.Comment: 10 pages, 7 figures, minor edits and reference adde

Emergence of supersymmetry on the surface of three dimensional topological insulators

We propose two possible experimental realizations of a 2+1 dimensional spacetime supersymmetry at a quantum critical point on the surface of three dimensional topological insulators. The quantum critical point between the semi-metallic state with one Dirac fermion and the s-wave superconducting state on the surface is described by a supersymmetric conformal field theory within $\epsilon$-expansion. We predict the exact voltage dependence of the differential conductance at the supersymmetric critical point.Comment: 8 pages, 2 figures; published versio

Synergistic Signals for Natural Cytotoxicity Are Required to Overcome Inhibition by c-Cbl Ubiquitin Ligase

SummaryNatural killer (NK) cell cytotoxicity toward target cells depends on synergistic coactivation by NK cell receptors such as NKG2D and 2B4. How synergy occurs is not known. Synergistic phosphorylation of phospholipase PLC-γ2, Ca2+ mobilization, and degranulation triggered by NKG2D and 2B4 coengagement were blocked by Vav1 siRNA knockdown, but enhanced by knockdown of c-Cbl. c-Cbl inhibited Vav1-dependent signals, given that c-Cbl knockdown did not rescue the Vav1 defect. Moreover, c-Cbl knockdown and Vav1 overexpression each circumvented the necessity for synergy because NKG2D or 2B4 alone became sufficient for activation. Thus, synergy requires not strict complementation but, rather, strong Vav1 signals to overcome inhibition by c-Cbl. Inhibition of NK cell cytotoxicity by CD94-NKG2A binding to HLA-E on target cells was dominant over synergistic activation, even after c-Cbl knockdown. Therefore, NK cell activation by synergizing receptors is regulated at the level of Vav1 by a hierarchy of inhibitory mechanisms

Supersymmetry Breaking and Moduli Stabilization with Anomalous U(1) Gauge Symmetry

We examine the effects of anomalous U(1)_A gauge symmetry on soft supersymmetry breaking terms while incorporating the stabilization of the modulus-axion multiplet responsible for the Green-Schwarz (GS) anomaly cancellation mechanism. In case of the KKLT stabilization of the GS modulus, soft terms are determined by the GS modulus mediation, the anomaly mediation and the U(1)_A mediation which are generically comparable to each other, thereby yielding the mirage mediation pattern of superparticle masses at low energy scale. Independently of the mechanism of moduli stabilization and supersymmetry breaking, the U(1)_A D-term potential can not be an uplifting potential for de Sitter vacuum when the gravitino mass is smaller than the Planck scale by many orders of magnitude. We also discuss some features of the supersymmetry breaking by red-shifted anti-brane which is a key element of the KKLT moduli stabilization.Comment: 32 pages; references are adde

Research Article ( − 1)-Step Derivations on -Groupoids: The Case = 3

We define a ranked trigroupoid as a natural followup on the idea of a ranked bigroupoid. We consider the idea of a derivation on such a trigroupoid as representing a two-step process on a pair of ranked bigroupoids where the mapping is a self-derivation at each step. Following up on this idea we obtain several results and conclusions of interest. We also discuss the notion of a couplet ( , ) on , consisting of a two-step derivation and its square = ∘ , for example, whose defining property leads to further observations on the underlying ranked trigroupoids also

Sphingosine 1-Phosphate Activation of EGFR as a Novel Target for Meningitic \u3cem\u3eEscherichia coli\u3c/em\u3e Penetration of the Blood-Brain Barrier

Central nervous system (CNS) infection continues to be an important cause of mortality and morbidity, necessitating new approaches for investigating its pathogenesis, prevention and therapy. Escherichia coli is the most common Gram-negative bacillary organism causing meningitis, which develops following penetration of the blood–brain barrier (BBB). By chemical library screening, we identified epidermal growth factor receptor (EGFR) as a contributor to E. coli invasion of the BBB in vitro. Here, we obtained the direct evidence that CNS-infecting E. coli exploited sphingosine 1-phosphate (S1P) for EGFR activation in penetration of the BBB in vitro and in vivo. We found that S1P was upstream of EGFR and participated in EGFR activation through S1P receptor as well as through S1P-mediated up-regulation of EGFR-related ligand HB-EGF, and blockade of S1P function through targeting sphingosine kinase and S1P receptor inhibited EGFR activation, and also E. coli invasion of the BBB. We further found that both S1P and EGFR activations occurred in response to the same E. coli proteins (OmpA, FimH, NlpI), and that S1P and EGFR promoted E. coli invasion of the BBB by activating the downstream c-Src. These findings indicate that S1P and EGFR represent the novel host targets for meningitic E. coli penetration of the BBB, and counteracting such targets provide a novel approach for controlling E. coli meningitis in the era of increasing resistance to conventional antibiotics

Isolation and characterization of differentially expressed genes in the mycelium and fruit body of Pleurotus ostreatus

The fruiting body of one of the most widely cultivated mushrooms, the oyster mushroom (Pleurotus ostreatus) is highly interesting, both commercially and scientifically. In the present study, we performed comparative proteomic profiling of P. ostreatus at two unique developmental stages; mycelium and fruit body, using two-dimensional gel electrophoresis (2-DE). Seven hundred fourteen (714) spots were detected and 29 spots (showing a high level of difference in their expressions) were identified by tandem mass spectrometry and basic local alignment search tool (BLAST) searching of an expressed sequence tag (EST) database of P. ostreatus. Among them, six proteins (putative fatty acid oxygenase, heat shock sks2, PriA homologue, Ap-1 like transcription factor YAP7, mung bean seed albumin, and C2H2 Zinc finger domain protein) and one protein (peroxisomal biogenesis factor 6) showed increased expression levels at the fruiting process and the mycelial stage, respectively. Through reverse transcriptase-polymerase chain reaction analysis, priA homologue and AP-1 like transcription factor yap7 showed gradually increased expression from mycelia to fruit body, whereas putative fatty acid oxygenase and heat shock protein sks2 were expressed only in the fruit body. These results provide useful information for future studies of mushroom development of P. ostreatus.Keywords: Developmental stage, mushroom fruiting, Pleurotus ostreatus, protein, two-dimensional gel electrophoresisAfrican Journal of Biotechnology Vol. 12(24), pp. 3790-379