Eicosapentaenoic Acid Ameliorates Non-Alcoholic Steatohepatitis in a Novel Mouse Model Using Melanocortin 4 Receptor-Deficient Mice

<div><p>Many attempts have been made to find novel therapeutic strategies for non-alcoholic steatohepatitis (NASH), while their clinical efficacy is unclear. We have recently reported a novel rodent model of NASH using melanocortin 4 receptor-deficient (MC4R-KO) mice, which exhibit the sequence of events that comprise hepatic steatosis, liver fibrosis, and hepatocellular carcinoma with obesity-related phenotypes. In the liver of MC4R-KO mice, there is a unique histological feature termed hepatic crown-like structures (hCLS), where macrophages interact with dead hepatocytes and fibrogenic cells, thereby accelerating inflammation and fibrosis. In this study, we employed MC4R-KO mice to examine the effect of highly purified eicosapentaenoic acid (EPA), a clinically available <i>n</i>-3 polyunsaturated fatty acid, on the development of NASH. EPA treatment markedly prevented the development of hepatocyte injury, hCLS formation and liver fibrosis along with lipid accumulation. EPA treatment was also effective even after MC4R-KO mice developed NASH. Intriguingly, improvement of liver fibrosis was accompanied by the reduction of hCLS formation and plasma kallikrein-mediated transforming growth factor-β activation. Moreover, EPA treatment increased the otherwise reduced serum concentrations of adiponectin, an adipocytokine with anti-inflammatory and anti-fibrotic properties. Collectively, EPA treatment effectively prevents the development and progression of NASH in MC4R-KO mice along with amelioration of hepatic steatosis. This study unravels a novel anti-fibrotic mechanism of EPA, thereby suggesting a clinical implication for the treatment of NASH.</p></div

Effect of EPA on liver injury and fibrosis in MC4R-KO mice.

<p>Fibrillar collagen deposition evaluated by Masson-trichrome staining (A) and fibrosis scores (B) at 24 weeks. Inset: Representative image of hepatocyte ballooning. Sirius red staining (C) and quantification of Sirius red-positive area (D). Scores of steatosis, lobular inflammation, ballooning degeneration (E) and non-alcoholic fatty liver disease activity score (NAS) (F). Scale bars, 50 μm. * <i>P</i> < 0.05; ** <i>P</i> < 0.01; n.s., not significant; n.d., not detected. WT-SD, <i>n</i> = 8; MC4R-control, <i>n</i> = 7; MC4R-EPA Pre, <i>n</i> = 10.</p

Serological parameters of MC4R-KO and WT mice treated with EPA for 24 weeks.

<p>WT, wildtype; SD, standard diet; BG, blood glucose; TG, triglyceride; FFA, free fatty acid; TC, total cholesterol; ALT, alanine aminotransferase. Data are expressed as the mean ± SE.</p><p>**<i>P</i> < 0.01 vs. WT-SD</p><p>^¶<i>P</i> < 0.01 vs. MC4R-Control. <i>n</i> = 7–10</p><p>Serological parameters of MC4R-KO and WT mice treated with EPA for 24 weeks.</p

Effect of EPA on hepatic mRNA expression in MC4R-KO mice.

<p>Hepatic mRNA expression levels after 24 weeks of EPA treatment. mRNA expression of genes related to <i>de novo</i> lipogenesis (fatty acid synthase (FAS) and stearoyl-CoA desaturase (SCD-1)) (A), β-oxidation (peroxisome proliferators-activated receptor α PPARα and carnitine palmitoyltransferase 1A (CTP-1A)) (B), inflammatory markers (F4/80 and tumor necrosis factor α (TNFα) (C) and fibrogenic factors (transforming growth factor β1 (TGFβ1), collagen α1(I) (COL1A1), tissue inhibitor of metalloproteinase-1 (TIMP1) and matrix metalloproteinase-2 (MMP2)) (D). * <i>P</i> < 0.05; ** <i>P</i> < 0.01; n.s., not significant. WT-SD, <i>n</i> = 8; MC4R-control, <i>n</i> = 7; MC4R-EPA Pre, <i>n</i> = 10.</p

Body weight and tissue weights in MC4R-KO mice treated with EPA for 24 weeks.

<p>(A) Experimental protocol of preventive EPA treatment. Growth curve (B) and weights of the subcutaneous, epididymal and mesenteric white adipose tissues (C) and liver (D) of male MC4R-KO (MC4R) and wildtype (WT) mice. WT-SD, WT mice fed standard diet (SD); MC4R-control, MC4R-KO mice fed Western diet (WD) supplemented with 5% (wt/wt) palmitate; MC4R-EPA Pre, MC4R-KO mice fed WD supplemented with 5% (wt/wt) EPA for 24 weeks. Open circle, WT-SD; Open triangle, MC4R-control; closed square, MC4R-EPA Pre. (E) Liver triglyceride (TG) content at 24 weeks. (F) Insulin tolerance test (ITT) at 12-week WD feeding. Open triangle, MC4R-control; closed square, MC4R-EPA Pre. ** <i>P</i> < 0.01; n.s., not significant. WT-SD, <i>n</i> = 8; MC4R-control, <i>n</i> = 7; MC4R-EPA Pre, <i>n</i> = 10.</p

Histological analysis of the liver of MC4R-KO mice treated with EPA for 4 weeks after the development of NASH.

<p>(A) Experimental protocol of therapeutic EPA treatment. Fibrillar collagen deposition evaluated by Masson-trichrome staining (B) and fibrosis scores (C). (D) Quantification of Sirius red-positive area. Scores of steatosis, lobular inflammation, ballooning degeneration (E) and NAS (F). Scale bars, 50 μm. * <i>P</i> < 0.05; ** <i>P</i> < 0.01; n.s., not significant. MC4R-control, <i>n</i> = 7; MC4R-EPA Pre, <i>n</i> = 10.</p

Effect of EPA on hCLS formation and apoptosis in the liver of MC4R-KO mice.

<p>(A) F4/80 immunostaining of the liver after 24 weeks of EPA treatment. Arrows indicate characteristic histological features termed “hepatic crown-like structures (hCLS)”. (B) Immunofluorescent staining for F4/80 (green) and CD11c (red). (C) Hepatic mRNA expression of CD11c. (D) TdT mediated dUTP-biotin nick end labeling (TUNEL) immunostaining and the number of TUNEL-positive cells. Arrowheads indicate TUNEL-positive cells. Correlation of the number of hCLS and the fibrosis area (E) and the number of TUNEL-positive cells (F). Scale bars, 50 μm. * <i>P</i> < 0.05; ** <i>P</i> < 0.01; n.d., not detected. WT-SD, <i>n</i> = 8; MC4R-control, <i>n</i> = 7; MC4R-EPA Pre, <i>n</i> = 10.</p

Effect of EPA on hepatic TGFβ activation in MC4R-KO mice.

<p>(A) Immmunostaining with anti-R58 LAP-DP antibody to determine TGFβ activation in the liver after 24 weeks of EPA treatment. (B) Quantification of the R58 LAP-DP-positive area. (C) Hepatic mRNA expression of urokinase-type plasminogen activator receptor (uPAR). (D) Active TGFβ protein levels in the liver. Scale bars, 50 μm. * <i>P</i> < 0.05; ** <i>P</i> < 0.01. WT-SD, <i>n</i> = 8; MC4R-control, <i>n</i> = 7; MC4R-EPA Pre, <i>n</i> = 10.</p

Collision detection on transmission lines with optical interferometer

V diplomski nalogi skušamo ugotoviti, v kolikšni meri je možno zaznavati in klasificirati trke na jeklenicah daljnovodov z optičnim interferometrom. Na začetku predstavimo osnovne pojme interferometrije in opišemo uporabljen optični interferometer. V jedru diplomske naloge natančneje opišemo eksperimentalni protokol in obdelavo signalov. Nadaljujemo z implementacijo algoritmov za segmentacijo in klasifikacijo zajetih signalov ter predstavimo dobljene rezultate. Segmentacijo izvedemo v domeni števila prehodov signala skozi ničlo, za klasifikacijo pa uporabimo večplastno nevronsko mrežo z algoritmom vzvratnega učenja. Rezultati študije nakazujejo, da sta implementirani segmentacija in klasifikacija uspešni v 77 % izvedenih trkov različnih predmetov.We analyse feasibility of collision detection on transmission lines with optical interferometer. We first provide a brief introduction into interferometry, along with a description of the optical interferometer used for measurements in this study. Afterwards, we describe the conducted experimental protocol and signal processing methodology. The focus is on implementation of algorithms for signal segmentation and collision classification. We used zero-crossing algorithm to transform signals into segmentation domain. Classification of collisions is done with a multilayer neural network trained by the backpropagation algorithm. The results demonstrate an average success rate of 77% for segmentation and classification of collision with five different objects

Sistematización de la experiencia de un ambiente de aprendizaje enriquecido por TIC durante la práctica clínica en fisioterapia cardiopulmonar en un hospital de nivel II de la ciudad de Cali

Esta investigación se centra en la caracterización de la experiencia de 4 estudiantes de fisioterapia de IX semestre de la Institución Universitaria Escuela Nacional del Deporte (IUEND) durante la implementación de un ambiente de aprendizaje enriquecido con Tecnologías de la Información y la Comunicación (TIC) en la práctica clínico – asistencial en Salud Cardiopulmonar; la cual se fundamenta en el hacer y pone a prueba las bases conceptuales del ciclo de fundamentación; todo esto con el fin de identificar las experiencias significativas que facilitan el aprendizaje y desarrollo de competencias clínicas, además analizar si este tipo de estrategias de enseñanza -aprendizaje permite al estudiante y al docente asesor superar inconvenientes propios de la práctica clínica como: optimizar tiempos de atención a pacientes, estudio independiente y trabajo colaborativo, retomar e integrar gran cantidad de conceptos y procedimientos aprendidos en IV semestre con las nuevas experiencias y la realidad del paciente; y a la vez cumplir con funciones administrativas propios del rol del fisioterapeuta asistencial (estadística, indicadores, desarrollo de guías, etc.) que dificultan el proceso de aprendizaje; concluyendo que los ambientes mediados por TIC pueden lograr superar estas dificultades y favorecer finalmente el aprendizaje significativo (juicio clínico), en el que se fundamenta el ciclo de práctica profesional