Electrical acupuncture increases protein synthesis through downregulation of let-7

Abstract Background: Our previous study found that acupuncture with low frequency electrical stimulation (Acu/LFES) prevents muscle atrophy by attenuation of protein degradation in chronic kidney disease. However, it is not clear whether Acu/LFES can increase protein synthesis in skeletal muscle. Methods: Normal C57/BL6 mice were given Acu/LFES treatment, applied for 30 minutes once. Gastrocnemius and triceps brachii muscles were harvested at 0, 6, 24, 48 and 72 hours after treatment. Protein synthesis was measured by the surface sensing of translation (SUnSET) assay. Exosomes were harvested using serial centrifugations and subjected to microRNA deep sequencing. The mature microRNA library was validated using a High Sensitivity DNA chip. The Student’s t-test and ANOVA were used for statistics. Results: Protein synthesis was enhanced in the both hindlimb (gastrocnemius) and forelimb (triceps brachii) muscles. To identify how exosomes regulate protein synthesis, we performed microRNA deep sequencing in serum exosomes isolated from treated and untreated mice and found that the 34 microRNAs were altered by Acu/LFES. Specifically, five members of the let-7 miRNA family were significantly decreased in the Acu/LFES treated mice. Blocking exosome secretion using GW4869 before treatment decreased the Acu/LFES-induced increases in protein synthesis. This provided evidence that the increased protein synthesis in response to Acu/LFES is exosome mediated. In cultured C2C12 myotubes, overexpressing let-7c-5p resulted in decreased protein synthesis. Conversely, inhibition of let-7c not only increased protein synthesis, but also increased the expression of Igf1, Igf1 receptor, insulin receptor and Igf2 receptor mRNA. In addition, inhibiting let-7c resulted in enhanced protein abundance of Igf1, Igf1 receptor, mTOR and p70S6. In silico searching suggested that let-7 could target Igf1. Using a luciferase reporter assay, we demonstrated that let-7 directly inhibited Igf1. Conclusions: Acu/LFES increases protein synthesis through a mechanism related with exosome secretion. Acu/LFES on hindlimb decreases let-7-5p in serum exosomes leading to upregulation of the Igf1 signaling pathway and increasing protein synthesis in both hindlimb and forelimb skeletal muscles.

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Downregulation of let-7 by Electrical Acupuncture Increases Protein Synthesis in Mice

Frontiers in Physiology ◽

10.3389/fphys.2021.697139 ◽

2021 ◽

Vol 12 ◽

Author(s):

Ying Huang ◽

Manshu Yu ◽

Akihiro Kuma ◽

Janet D. Klein ◽

Yanhua Wang ◽

...

Keyword(s):

Protein Synthesis ◽

Skeletal Muscles ◽

Muscle Protein ◽

Muscle Protein Synthesis ◽

High Sensitivity ◽

Luciferase Reporter ◽

C2c12 Myotubes ◽

Electrical Acupuncture ◽

The Impact ◽

Serum Exosomes

BackgroundOur previous study found that acupuncture with low frequency electrical stimulation (Acu/LFES) prevents muscle atrophy by attenuation of protein degradation in mice. The current study examines the impact of Acu/LFES on protein synthesis.MethodC57/BL6 mice received Acu/LFES treatment on hindlimb for 30 min once. Acu/LFES points were selected by WHO Standard Acupuncture Nomenclature and electric stimulation applied using an SDZ-II Electronic acupuncture instrument. Muscle protein synthesis was measured by the surface-sensing of translation (SUnSET) assay. Exosomes were isolated using serial centrifugation and concentration and size of the collected exosomes were measured using a NanoSight instrument. The mature microRNA library in serum exosomes was validated using a High Sensitivity DNA chip.ResultsProtein synthesis was enhanced in the both hindlimb and forelimb muscles. Blocking exosome secretion with GW4869 decreased the Acu/LFES-induced increases in protein synthesis. MicroRNA-deep sequencing demonstrated that four members of the Let-7 miRNA family were significantly decreased in serum exosomes. Real time qPCR further verified Acu/LFES-mediated decreases of let-7c-5p in serum exosomes and skeletal muscles. In cultured C2C12 myotubes, inhibition of let-7c not only increased protein synthesis, but also enhanced protein abundance of Igf1 and Igf1 receptors. Using a luciferase reporter assay, we demonstrated that let-7 directly inhibits Igf1.ConclusionAcu/LFES on hindlimb decreases let-7-5p leading to upregulation of the Igf1 signaling and increasing protein synthesis in both hindlimb and forelimb skeletal muscles. This provides a new understanding of how the electrical acupuncture treatment can positively influence muscle health.

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Magnetoelastic Coupling and Delta-E Effect in Magnetoelectric Torsion Mode Resonators

Sensors ◽

10.3390/s21062022 ◽

2021 ◽

Vol 21 (6) ◽

pp. 2022

Author(s):

Benjamin Spetzler ◽

Elizaveta V. Golubeva ◽

Ron-Marco Friedrich ◽

Sebastian Zabel ◽

Christine Kirchhof ◽

...

Keyword(s):

Low Frequency ◽

High Sensitivity ◽

Element Model ◽

Mode Number ◽

Frequency Change ◽

General Description ◽

Resonance Modes ◽

Field Sensor ◽

Magnetic Sensitivity ◽

Bending Modes

Magnetoelectric resonators have been studied for the detection of small amplitude and low frequency magnetic fields via the delta-E effect, mainly in fundamental bending or bulk resonance modes. Here, we present an experimental and theoretical investigation of magnetoelectric thin-film cantilevers that can be operated in bending modes (BMs) and torsion modes (TMs) as a magnetic field sensor. A magnetoelastic macrospin model is combined with an electromechanical finite element model and a general description of the delta-E effect of all stiffness tensor components Cij is derived. Simulations confirm quantitatively that the delta-E effect of the C66 component has the promising potential of significantly increasing the magnetic sensitivity and the maximum normalized frequency change ∆fr. However, the electrical excitation of TMs remains challenging and is found to significantly diminish the gain in sensitivity. Experiments reveal the dependency of the sensitivity and ∆fr of TMs on the mode number, which differs fundamentally from BMs and is well explained by our model. Because the contribution of C11 to the TMs increases with the mode number, the first-order TM yields the highest magnetic sensitivity. Overall, general insights are gained for the design of high-sensitivity delta-E effect sensors, as well as for frequency tunable devices based on the delta-E effect.

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Enhanced specificity of clinical high-sensitivity tumor mutation profiling in cell-free DNA via paired normal sequencing using MSK-ACCESS

Nature Communications ◽

10.1038/s41467-021-24109-5 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

A. Rose Brannon ◽

Gowtham Jayakumaran ◽

Monica Diosdado ◽

Juber Patel ◽

Anna Razumova ◽

...

Keyword(s):

Cancer Patients ◽

De Novo ◽

Low Frequency ◽

High Sensitivity ◽

Clinical Analysis ◽

De Novo Mutation ◽

Cell Free Dna ◽

Free Dna ◽

Somatic Alterations ◽

Mutation Profiling

AbstractCirculating cell-free DNA from blood plasma of cancer patients can be used to non-invasively interrogate somatic tumor alterations. Here we develop MSK-ACCESS (Memorial Sloan Kettering - Analysis of Circulating cfDNA to Examine Somatic Status), an NGS assay for detection of very low frequency somatic alterations in 129 genes. Analytical validation demonstrated 92% sensitivity in de-novo mutation calling down to 0.5% allele frequency and 99% for a priori mutation profiling. To evaluate the performance of MSK-ACCESS, we report results from 681 prospective blood samples that underwent clinical analysis to guide patient management. Somatic alterations are detected in 73% of the samples, 56% of which have clinically actionable alterations. The utilization of matched normal sequencing allows retention of somatic alterations while removing over 10,000 germline and clonal hematopoiesis variants. Our experience illustrates the importance of analyzing matched normal samples when interpreting cfDNA results and highlights the importance of cfDNA as a genomic profiling source for cancer patients.

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Abstract 117: MicroRNA-138 regulates S100A1 in Endothelial Cells

Circulation Research ◽

10.1161/res.113.suppl_1.a117 ◽

2013 ◽

Vol 113 (suppl_1) ◽

Author(s):

Anagha Sen ◽

Shumei Ren ◽

Jianxin Sun ◽

Patrick Most ◽

Karsten Peppel

Keyword(s):

Gene Expression ◽

Endothelial Cells ◽

Reporter Gene ◽

Recombinant Adenovirus ◽

Limb Ischemia ◽

Bioinformatic Analysis ◽

Reporter Gene Expression ◽

Luciferase Reporter ◽

C2c12 Myotubes ◽

Luciferase Reporter Construct

Rationale: The EF-hand Ca2+ sensor S100A1 is essential for proper endothelial nitric oxide (NO) synthase (eNOS) activation. S100A1 levels are greatly reduced in endothelial cells (ECs) subjected to hypoxia, rendering them dysfunctional. Objective: To determine if the 3’UTR mediates the rapid hypoxia-induced downregulation of S100A1 in ECs. Methods and Results: ECs transfected with a S100A1 - 3’ untranslated region (UTR) luciferase reporter construct displayed significantly reduced gene expression when subjected to gas or chemical hypoxia. Bioinformatic analysis suggested that microRNA -138 (miR-138) could target the 3’UTR of S100A1. Hypoxia greatly increased miR-138 levels in ECs, but not in skeletal muscle C2C12 myotubes. Consistent with this finding, patients with critical limb ischemia (CLI) or mice subjected to femoral artery resection (FAR) displayed increased miR-138 levels. Transfection of a miR-138 mimic into ECs reduced S100A1 - 3 ‘UTR reporter gene expression, while transfection of an anti miR-138 (antagomir) prevented the hypoxia-induced downregulation of the reporter gene. The increased levels of miR-138 are dependent on Hif1-α activation as treatment with siRNA against Hif1-α prevented S100A1 reporter gene downregulation after hypoxia. Conversely, specific activation of Hif1-α by a selective prolyl-hydroxylase inhibitor (IOX2) reduced reporter gene expression. Finally, ECs transfected with miR-138 mimic displayed reduced tube formation when plated onto Matrigel matrix and expressed less NO when stimulated with VEGF. These effects were reversed by gene transfer of S100A1 using recombinant adenovirus. Conclusions: Our study shows that miR-138 is an essential mediator of EC dysfunction via its ability to target the 3’UTR of S100A1 in a hypoxia-induced manner. MiR-138 might thus be an attractive target for the treatment of pathologies that are linked to endothelial dysfunction.

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Low-frequency multiplex CARS microscopy with a high-repetition near-infrared supercontinuum laser

Applied Physics Express ◽

10.35848/1882-0786/ac39b1 ◽

2021 ◽

Author(s):

Yusuke Arashida ◽

Atsushi Taninaka ◽

Takayuki Ochiai ◽

Hiroyuki Mogi ◽

Shoji YOSHIDA ◽

...

Keyword(s):

Near Infrared ◽

High Efficiency ◽

Signal To Noise Ratio ◽

Low Frequency ◽

High Sensitivity ◽

High Repetition ◽

Spectrum Shaping ◽

Crystal Phase Transition ◽

Wavenumber Region ◽

Anti Stokes

Abstract We have developed a multiplex Coherent anti-Stokes Raman scattering (CARS) microscope effective for low-wavenumber measurement by combining a high-repetition supercontinuum light source of 1064 nm and an infrared high-sensitivity InGaAs diode array. This system could observe the low-wavenumber region down to 55 cm-1 with high sensitivity. In addition, using spectrum shaping and spectrum modulation techniques, we simultaneously realized a wide bandwidth (<1800 cm-1), high wavenumber resolution (9 cm-1), high efficiency, and increasing signal to noise ratio by reducing the effect of the background shape in low-wavenumber region. Spatial variation of a sulfur crystal phase transition with metastable states was visualized.

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PARAMETRIC AMPLIFICATION OF THE SIGNALS IN THE ELECTROSTATIC GRAVIINERTIAL SENSOR

Devices and Methods of Measurements ◽

10.21122/2220-9506-2017-8-2-108-121 ◽

2017 ◽

Vol 8 (2) ◽

pp. 108-121

Author(s):

I. Z. Gilavdary ◽

S. N. Mekid ◽

N. N. Riznookaya

Keyword(s):

Torsional Rigidity ◽

Low Frequency ◽

High Sensitivity ◽

Elastic Stiffness ◽

Parametric Amplification ◽

Distinctive Features ◽

Torsion Suspension ◽

Wide Range ◽

Differential Circuits ◽

Simultaneous Reading

The challenges of designing simple, reliable, and high sensitivity graviinertial sensors are investigated. The sensor comprises a proof mass (PM) and is fixed with the housing by the elastic torsion suspension. PM makes small rotations under the action of gravitational forces or inertial forces.The distinctive features of the sensor are that the differential electrostatic system provides simultaneous reading of the desired signal and a control the torsional rigidity of suspension. In addition, the PM's rotational angular velocity transforms in the alternating current flowing through the capacitors. The presence of аlternating current (AC) voltage sources allows to get the parametric amplification of AC and significantly to improve the sensitivity of the sensor. In the simplest case, the sensor does not contain any feedback circuits.As an example, calculations of the micromechanical linear accelerations confirm that the periodic modulation of the coefficient of elastic stiffness of the suspension can significantly increase the sensitivity in the low frequency range, even in the absence of parametric resonance.Conditions for suppressions of background current participating in the output signal from a parametric pumping due to the asymmetry of the differential circuits are set. The frequency characteristics calculations of the sensor were carried out. It is expected, that the proposed sensor design ensures minimum noise level, which can be achievable in the graviinertial sensors. This design and the constructed theory can serve as a basis for creating a wide range of graviinertial devices operating on a movable base, for example, linear and angular accelerometer, gravity gradiometer, gravimeters, and inclinometers, which can be realized in the hybrid and in the micromechanical versions.

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Proteasome- and Calpain-Mediated Proteolysis, but Not Autophagy, Is Required for Leucine-Induced Protein Synthesis in C2C12 Myotubes

Physiologia ◽

10.3390/physiologia1010005 ◽

2021 ◽

Vol 1 (1) ◽

pp. 22-33

Author(s):

Shelby C. Osburn ◽

Christopher G. Vann ◽

David D. Church ◽

Arny A. Ferrando ◽

Michael D. Roberts

Keyword(s):

Protein Synthesis ◽

Muscle Protein ◽

Muscle Protein Synthesis ◽

Muscle Growth ◽

Proteasome Inhibition ◽

Coupled Processes ◽

C2c12 Myotubes ◽

Calpain Inhibitor ◽

Tightly Coupled

Muscle protein synthesis and proteolysis are tightly coupled processes. Given that muscle growth is promoted by increases in net protein balance, it stands to reason that bolstering protein synthesis through amino acids while reducing or inhibiting proteolysis could be a synergistic strategy in enhancing anabolism. However, there is contradictory evidence suggesting that the proper functioning of proteolytic systems in muscle is required for homeostasis. To add clarity to this issue, we sought to determine if inhibiting different proteolytic systems in C2C12 myotubes in conjunction with acute and chronic leucine treatments affected markers of anabolism. In Experiment 1, myotubes underwent 1-h, 6-h, and 24-h treatments with serum and leucine-free DMEM containing the following compounds (n = 6 wells per treatment): (i) DMSO vehicle (CTL), (ii) 2 mM leucine + vehicle (Leu-only), (iii) 2 mM leucine + 40 μM MG132 (20S proteasome inhibitor) (Leu + MG132), (iv) 2 mM leucine + 50 μM calpeptin (calpain inhibitor) (Leu + CALP), and (v) 2 mM leucine + 1 μM 3-methyladenine (autophagy inhibitor) (Leu + 3MA). Protein synthesis levels significantly increased (p < 0.05) in the Leu-only and Leu + 3MA 6-h treatments compared to CTL, and levels were significantly lower in Leu + MG132 and Leu + CALP versus Leu-only and CTL. With 24-h treatments, total protein yield was significantly lower in Leu + MG132 cells versus other treatments. Additionally, the intracellular essential amino acid (EAA) pool was significantly greater in 24-h Leu + MG132 treatments versus other treatments. In a follow-up experiment, myotubes were treated for 48 h with CTL, Leu-only, and Leu + MG132 for morphological assessments. Results indicated Leu + MG132 yielded significantly smaller myotubes compared to CTL and Leu-only. Our data are limited in scope due to the utilization of select proteolysis inhibitors. However, this is the first evidence to suggest proteasome and calpain inhibition with MG132 and CALP, respectively, abrogate leucine-induced protein synthesis in myotubes. Additionally, longer-term Leu + MG132 treatments translated to an atrophy phenotype. Whether or not proteasome inhibition in vivo reduces leucine- or EAA-induced anabolism remains to be determined.

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A broadband two axis flux-gate magnetometer

Annals of Geophysics ◽

10.4401/ag-4356 ◽

1998 ◽

Vol 41 (3) ◽

Author(s):

P. Palangio

Keyword(s):

Magnetic Field ◽

Low Frequency ◽

High Sensitivity ◽

Magnetic Sensors ◽

Frequency Range ◽

Field Station ◽

Low Weight ◽

Highly Sensitive ◽

Flux Gate ◽

Magnetic Field Variations

A broadband two axis flux-gate magnetometer was developed to obtain high sensitivity in magnetotelluric measurements. In magnetotelluric sounding, natural low frequency electromagnetic fields are used to estimate the conductivity of the Earth's interior. Because variations in the natural magnetic field have small amplitude(10-100 pT) in the frequency range 1 Hz to 100 Hz, highly sensitive magnetic sensors are required. In magnetotelluric measurements two long and heavy solenoids, which must be installed, in the field station, perpendicular to each other (north-south and east-west) and levelled in the horizontal plane are used. The coil is a critical component in magnetotelluric measurements because very slight motions create noise voltages, particularly troublesome in wooded areas; generally the installation takes place in a shallow trench. Moreover the coil records the derivative of the variations rather than the magnetic field variations, consequently the transfer function (amplitude and phase) of this sensor is not constant throughout the frequency range 0.001-100 Hz. The instrument, developed at L'Aquila Geomagnetic Observatory, has a flat response in both amplitude and phase in the frequency band DC-100 Hz, in addition it has low weight, low power, small volume and it is easier to install in the field than induction magnetometers. The sensivity of this magnetometer is 10 pT rms.

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Effects of temperature variations in high-sensitivity Sagnac gyroscope

The European Physical Journal Plus ◽

10.1140/epjp/s13360-021-01470-4 ◽

2021 ◽

Vol 136 (5) ◽

Author(s):

Andrea Basti ◽

Nicolò Beverini ◽

Filippo Bosi ◽

Giorgio Carelli ◽

Donatella Ciampini ◽

...

Keyword(s):

Earth Rotation ◽

Mechanical Design ◽

Low Frequency ◽

Environmental Parameters ◽

High Sensitivity ◽

Rotation Axes ◽

The Earth ◽

Sagnac Gyroscope ◽

Laser Gyroscopes

AbstractGINGERINO is one of the most sensitive Sagnac laser-gyroscopes based on an heterolithic mechanical structure. It is a prototype for GINGER, the laser gyroscopes array proposed to reconstruct the Earth rotation vector and in this way to measure General Relativity effects. Many factors affect the final sensitivity of laser gyroscopes, in particular, when they are used in long-term measurements, slow varying environmental parameters come into play. To understand the role of different terms allows to design more effective mechanical as well as optical layouts, while a proper model of the dynamics affecting long-term (low frequency) signals would increase the effectiveness of the data analysis for improving the overall sensitivity. In this contribution, we focus our concerns on the effects of room temperature and pressure aiming at further improving mechanical design and long-term stability of the apparatus. Our data are compatible with a local orientation changes of the Gran Sasso site below $$\mu $$ μ rad as predicted by geodetic models. This value is consistent with the requirements for GINGER and the installation of an high-sensitivity Sagnac gyroscope oriented at the maximum signal, i.e. along the Earth rotation axes.

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