32 research outputs found

    Depletion of Myostatin b Promotes Somatic Growth and Lipid Metabolism in Zebrafish

    Get PDF
    Myostatin (MSTN) is a negative regulator of myogenesis in vertebrates. Depletion of mstn resulted in elevated muscle growth in several animal species. However, the report on the complete ablation of mstn in teleost fish has not yet become available. In this study, two independent mstnb-deficient mutant lines in zebrafish were generated with the TALENs technique. In the mstnb-deficient zebrafish, enhanced muscle growth with muscle fiber hyperplasia was achieved. Beginning at the adult stage (80 days postfertilization), the mstnb-deficient zebrafish exhibited increased circumferences and body weights compared with the wild-type sibling control fish. Although the overall total lipid/body weight ratios remained similar between the mstnb-deficient zebrafish and the control fish, the distribution of lipids was altered. The size of the visceral adipose tissues became smaller while more lipids accumulated in skeletal muscle in the mstnb-deficient zebrafish than in the wild-type control fish. Based on the transcriptional expression profiles, our results revealed that lipid metabolism, including lipolysis and lipogenesis processes, was highly activated in the mstnb-deficient zebrafish, which indicated the transition of energy metabolism from protein-dependent to lipid-dependent in mstnb-deficient zebrafish. Our mstnb-deficient model could be valuable in understanding not only the growth trait regulation in teleosts but also the mechanisms of teleost energy metabolism

    Optimization of Extraction Process by Response Surface Method and Analysis of Antioxidant Activity in Vitro of Total Flavonoids from Abrus precatorius Linn

    Get PDF
    The objective of this study was to optimize the extraction process of flavonoids from Abrus precatorius Linn, and explored its antioxidant activity. Ethanol volume fraction, solid-liquid ratio, ultrasonic energy and ultrasonic extracting time as variables, the yield of flavonoids as evaluation index, single factor tests and Box-Behnken method were used to optimize the extraction process. The scavenging ability on DPPH, ABTS+ free radicals, and the reducing power of flavonoids from Abrus precatorius Linn were also detected to estimate the antioxidant activities. Results showed that, when solid-liquid ratio reached 1:50, the optimum extraction process (0.696%, highest yield) could be achieved under condition of ethanol volume fraction 82%, ultrasonic energy 507 J and ultrasonic extracting time 42 min. Half effective concentration being EC50 0.028 and 0.009 mg/mL respectively. Abrus precatorius Linn flavonoids were able to scavenge DPPH and ABTS+ free radicals effectively, and its ability risen as mass concentration increases, meaning it is superior to Trolox. When flavonoid concentration was set at 5 mg/mL, the reducing power on iron ion reached 2.42 mmol/L, which was weaker than Trolox. To sum up, ultrasonic extraction technology can be effectively employed to the extraction of Abrus precatorius Linn flavonoids, resulting in better antioxidant activity

    OsHAC1;1 and OsHAC1;2 function as arsenate reductases and regulate arsenic accumulation

    Get PDF
    Rice is a major dietary source of the toxic metalloid arsenic (As). Reducing its accumulation in rice (Oryza sativa) grain is of critical importance to food safety. Rice roots take up arsenate and arsenite depending on the prevailing soil conditions. The first step of arsenate detoxification is its reduction to arsenite, but the enzyme(s) catalyzing this reaction in rice remains unknown. Here, we identify OsHAC1;1 and OsHAC1;2 as arsenate reductases in rice. OsHAC1;1 and OsHAC1;2 are able to complement an Escherichia coli mutant lacking the endogenous arsenate reductase and to reduce arsenate to arsenite. OsHAC1:1 and OsHAC1;2 are predominantly expressed in roots, with OsHAC1;1 being abundant in the epidermis, root hairs, and pericycle cells while OsHAC1;2 is abundant in the epidermis, outer layers of cortex, and endodermis cells. Expression of the two genes was induced by arsenate exposure. Knocking out OsHAC1;1 or OsHAC1;2 decreased the reduction of arsenate to arsenite in roots, reducing arsenite efflux to the external medium. Loss of arsenite efflux was also associated with increased As accumulation in shoots. Greater effects were observed in a double mutant of the two genes. In contrast, overexpression of either OsHAC1;1 or OsHAC1;2 increased arsenite efflux, reduced As accumulation, and enhanced arsenate tolerance. When grown under aerobic soil conditions, overexpression of either OsHAC1;1 or OsHAC1;2 also decreased As accumulation in rice grain, whereas grain As increased in the knockout mutants. We conclude that OsHAC1;1 and OsHAC1;2 are arsenate reductases that play an important role in restricting As accumulation in rice shoots and grain

    Genome-wide association mapping identifies a new arsenate reductase enzyme critical for limiting arsenic accumulation in plants

    Get PDF
    Inorganic arsenic is a carcinogen, and its ingestion through foods such as rice presents a significant risk to human health. Plants chemically reduce arsenate to arsenite. Using genome-wide association (GWA) mapping of loci controlling natural variation in arsenic accumulation in Arabidopsis thaliana allowed us to identify the arsenate reductase required for this reduction, which we named High Arsenic Content 1 (HAC1). Complementation verified the identity of HAC1, and expression in Escherichia coli lacking a functional arsenate reductase confirmed the arsenate reductase activity of HAC1. The HAC1 protein accumulates in the epidermis, the outer cell layer of the root, and also in the pericycle cells surrounding the central vascular tissue. Plants lacking HAC1 lose their ability to efflux arsenite from roots, leading to both increased transport of arsenic into the central vascular tissue and on into the shoot. HAC1 therefore functions to reduce arsenate to arsenite in the outer cell layer of the root, facilitating efflux of arsenic as arsenite back into the soil to limit both its accumulation in the root and transport to the shoot. Arsenate reduction by HAC1 in the pericycle may play a role in limiting arsenic loading into the xylem. Loss of HAC1-encoded arsenic reduction leads to a significant increase in arsenic accumulation in shoots, causing an increased sensitivity to arsenate toxicity. We also confirmed the previous observation that the ACR2 arsenate reductase in A. thaliana plays no detectable role in arsenic metabolism. Furthermore, ACR2 does not interact epistatically with HAC1, since arsenic metabolism in the acr2 hac1 double mutant is disrupted in an identical manner to that described for the hac1 single mutant. Our identification of HAC1 and its associated natural variation provides an important new resource for the development of low arsenic-containing food such as rice

    Robust estimation of bacterial cell count from optical density

    Get PDF
    Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

    Protective Effects and Target Network Analysis of Ginsenoside Rg1 in Cerebral Ischemia and Reperfusion Injury: A Comprehensive Overview of Experimental Studies

    No full text
    Cerebral ischemia-reperfusion is a complicated pathological process. The injury and cascade reactions caused by cerebral ischemia and reperfusion are characterized by high mortality, high recurrence, and high disability. However, only a limited number of antithrombotic drugs, such as recombinant tissue plasminogen activator (r-TPA), aspirin, and heparin, are currently available for ischemic stroke, and its safety concerns is inevitable which associated with reperfusion injury and hemorrhage. Therefore, it is necessary to further explore and examine some potential neuroprotective agents with treatment for cerebral ischemia and reperfusion injury to reduce safety concerns caused by antithrombotic drugs in ischemic stroke. Ginseng Rg1 (G-Rg1) is a saponin composed of natural active ingredients and derived from the roots or stems of Panax notoginseng and ginseng in traditional Chinese medicine. Its pharmacological effects exert remarkable neurotrophic and neuroprotective effects in the central nervous system. To explore and summarize the protective effects and mechanisms of ginsenoside Rg1 against cerebral ischemia and reperfusion injury, we conducted this review, in which we searched the PubMed database to obtain and organize studies concerning the pharmacological effects and mechanisms of ginsenoside Rg1 against cerebral ischemia and reperfusion injury. This study provides a valuable reference and clues for the development of new agents to combat ischemic stroke. Our summarized review and analysis show that the pharmacological effects of and mechanisms underlying ginsenoside Rg1 activity against cerebral ischemia and reperfusion injury mainly involve 4 sets of mechanisms: anti-oxidant activity and associated apoptosis via the Akt, Nrf2/HO-1, PPARγ/HO-1, extracellular regulated protein kinases (ERK), p38, and c-Jun N-terminal kinase (JNK) pathways (or mitochondrial apoptosis pathway) and the caspase-3/ROCK1/MLC pathway; anti-inflammatory and immune stimulatory-related activities that involve apoptosis or necrosis via MAPK pathways (the JNK1/2 + ERK1/2 and PPARγ/HO-1 pathways), endoplasmic reticulum stress (ERS), high mobility group protein1 (HMGB1)-induced TLR2/4/9 and receptor for advanced glycation end products (RAGE) pathways, and the activation of NF-κB; neurological cell cycle, proliferation, differentiation, and regeneration via the MAPK pathways (JNK1/2 + ERK1/2, PI3K-Akt/mTOR, PKB/Akt and HIF-1α/VEGF pathways); and energy metabolism and the regulation of cellular ATP levels, the blood-brain barrier and other effects via N-methyl-D-aspartic acid (NMDA) receptors, ERS, and AMP/AMPK-GLUT pathways. Collectively, these mechanisms result in significant neuroprotective effects against cerebral ischemic injury. These findings will be valuable in that they should further promote the development of candidate drugs and provide more information to support the application of previous findings in stroke clinical trials

    CAT Computer Aided Design for Technical Systems - ein Werkzeug im Verbundvorhaben PROSYT CAT-Abschlussbericht

    No full text
    Within the framework of the project documented here, a portable program system including design and system tools was developed, which can be implemented for small applications on high-performance personal computers (performance classes CADMUS 9000, INTEL 86/300 or similar) and for major applications on a terminal or workstation network, supported by a data processing center, if required. The core of this system is represented by a tool frame system consisting of a powerful interactive system (text + graphics), a retrieval system, a universal data keeping system and the Project Advisor. In most cases existing tools will be ''hooked'' into this tool frame. In exceptional cases non-available tools were developed or existing tools were extended in a way desired by users. (orig./RHM)Im Rahmen des dokumentierten Vorhabens wurde ein portables Programmsystem, mit Entwurfs- und Systemproduktionswerkzeugen entwickelt, das fuer kleine Anwendungen auf leistungsfaehigen Personal-Computern (Leistungsklassen CADMUS 9000, INTEL 86/300 o.ae.), fuer grosse Anwendungen auf einem gegebenenfalls durch ein Rechenzentrum gestuetztes Terminal- oder Arbeitsplatzrechnernetz implementiert werden kann. Der Kern des Systems stellt ein Werkzeugrahmensystem dar, bestehend aus einem leistungsfaehigen Dialogsystem (Text + Grafik), einem Auskunftsystem, einem universellen Datenhaltungssystem und dem Projekt-Advisor. In diesen Werkzeugrahmen wurden vornehmlich existierende Werkzeuge ''eingehaengt''. In Ausnahmefaellen wurden fehlende Werkzeuge entwickelt, bzw. bestehende Werkzeuge in von den Anwendern gewuenschter Weise erweitert. (orig./RHM)SIGLEAvailable from TIB Hannover: F94B0292 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman
    corecore