Thrombotic Microangiopathy and Increased Nitrosative and Oxidative Stress in an Animal Model of Indu...
This presentation is the property of its rightful owner.
Sponsored Links
1 / 28

Introduction PowerPoint PPT Presentation


  • 37 Views
  • Uploaded on
  • Presentation posted in: General

Thrombotic Microangiopathy and Increased Nitrosative and Oxidative Stress in an Animal Model of Induced Sepsis 23rd European Congress of Pathology Helsinki, 2011. R Granados, L El Bouayadi, N Nin, A Ferruelo, C Sánchez, Y Rojas, P Cardinal, A Esteban, M de Paula, JA Lorente

Download Presentation

Introduction

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Introduction 4428772

Thrombotic Microangiopathy and Increased Nitrosative and Oxidative Stress in an Animal Model of Induced Sepsis23rd European Congress of PathologyHelsinki, 2011

R Granados, L El Bouayadi, N Nin, A Ferruelo, C Sánchez, Y Rojas, P Cardinal, A Esteban, M de Paula, JA Lorente

Hospital Universitario de Getafe, Madrid


Introduction

Introduction

  • Renal dysfunction in severely ill septic patients correlates with a very high mortality.

  • Sepsis is associated to an increase in oxidative stress causing impairment of systemic blood flow, damage of microvasculature and tissue hypoxia.

  • Since the physiopathological events are not fully understood, animal models are of great interest.


Objectives

Objectives

1.-To study the morphology of the lesions associated to sepsis.

2.-To measure the genetic expresion of some mediators of oxidative and nitrosative stress.

- Inducible Nitric Oxyde Synthase (iNOS)

- Tumor Necrosis factor (TNF)

- Nitrotyrosine (NT)

- Interleukine 6 (IL-6)

3.-To quantify the degree of protein nitration and oxydation.


Materials and methods i

Materials and Methods I

  • An experimental (n=16) intravenous 1.5x109 UFC/ml E. coli solution or control (n=9) sterile saline was injected in pigs.

  • E. Coli strain serogroup O101, negative for enterotoxins LT and Sta, verotoxins VT1 and VT2 or necrotizing cytotoxic factors CNF1 and CNF2.

  • Vital signs and renal blood flow was monitorized.


Introduction 4428772

  • Materials and Methods II

  • Histologicalanalysis:

    • Semiquantitativeanalysis of 24 glomerular, tubulointerstitial and vascular damagecriteria.

    • Nitrotyrosine and iNOSlocationby IF in renal cortex.

  • Serumlevels of cytokines and NGAL.

  • Gen expresionanalysisof iNOS, TNF, NT and IL-6 by RT-PCR or Western blot.


  • Results i

    Results I

    • All animals inoculated with E. Coli developed a hypodynamic pattern with low cardiac output and decreseased renal blood flow similar to that seen in septic patients.

    • There was acute glomerular damage with a thrombotic microangiopathy (TMA) pattern in 10 out of 16 cases (62,5%) of induced sepsis.

    • None of the control cases had TMA.


    Diffuse glomerular damage 50

    Diffuse glomerular damage (> 50%)


    Introduction 4428772

    Global glomerular damage


    Introduction 4428772

    Segmental glomerular damage


    Congesti n

    Congestión


    Mesangiolysis

    Mesangiolysis


    Introduction 4428772

    Focal Hyalinosis


    Introduction 4428772

    Ischemic changes


    Introduction 4428772

    Acute Tubular Necrosis


    Introduction 4428772

    PAS positive granules in proximal tubules


    Introduction 4428772

    Absence of vascular damage


    Results ii

    Results II

    NITRATION AND OXIDATION

    InflammatoryMediators


    Serum levels

    Serum levels

    TNF, IL-6 and NGAL were significantly elevated in septic animals

    TNF: 5109,9/0,13 ng/ug protein

    IL6: 1296/0,27 ng/ug protein

    NGAL: 1121,15/172,98 ng/ml


    Protein nitration by western blot

    Protein Nitration by Western Blot

    kDa

    Significant elevation of NT protein and iNOS was seen in the renal cortex of septic animals.

    NT: control: 3688, sepsis: 8900

    iNOS: control:7628, sepsis: 10776


    Tissue levels by rt pcr

    Tissue levels by RT-PCR

    RQ

    Increased gene expression of TNF, IL-6 and iNOS, was seen in renal cortex of septic animals

    TNF: 4,25

    IL6: 58,75

    iNOS: 6,17


    Thrombotic microangiopathy tma

    Thrombotic Microangiopathy (TMA)

    • Hemolytic Uremic Syndrome

    • Thrombotic Thrombocytopenic Purpura (TTP)

    • Preeclampsia and Eclampsia

    • Antiphospholipid Antibody Syndrome

    • Disseminated Intravascular Coagulation

    • Lupus

    • Esclerodermia

    • Severe Hypertension

    • HIV


    Conclusions

    Conclusions

    • Our sepsis-induced animal model reproduces the hemodynamic compromise and renal failure of septic patients.

    • Thrombotic microangiopathy (TMA) is the histological expression of the vascular damage caused by sepsis in this model.


    Conclusions1

    Conclusions

    • Increased oxidative and nitrosative activity and elevated inflammatory mediators are seen in serum and in renal cortical tissue.

    • The development of TMA is most probably the result of an increased thrombogenic effect of a damaged glomerular endothelium.


    Introduction 4428772

    Gracias

    Centro Nacional de Biotecnología, CSIC, Madrid, Spain. Juan Ortín, Lorena Ver


  • Login