Tissue inhibitor of metalloproteinases 3-dependent microvascular endothelial cell barrier function is disrupted under septic conditions

Am J Physiol Heart Circ Physiol. 2016 Jun 1;310(11):H1455-67. doi: 10.1152/ajpheart.00796.2015. Epub 2016 Mar 18.


Sepsis is associated with dysfunction of microvascular endothelial cells (MVEC) leading to tissue edema and multiple organ dysfunction. Metalloproteinases can regulate MVEC function through processing of cell surface proteins, and tissue inhibitor of metalloproteinases 3 (TIMP3) regulates metalloproteinase activity in the lung following injury. We hypothesize that TIMP3 promotes normal pulmonary MVEC barrier function through inhibition of metalloproteinase activity. Naive Timp3(-/-) mice had significantly higher basal pulmonary microvascular Evans blue (EB) dye-labeled albumin leak vs. wild-type (WT) mice. Additionally, cecal-ligation/perforation (CLP)-induced sepsis significantly increased pulmonary microvascular EB-labeled albumin leak in WT but not Timp3(-/-) mice. Similarly, PBS-treated isolated MVEC monolayers from Timp3(-/-) mice displayed permeability barrier dysfunction vs. WT MVEC, evidenced by lower transendothelial electrical resistance and greater trans-MVEC flux of fluorescein-dextran and EB-albumin. Cytomix (equimolar interferon γ, tumor necrosis factor α, and interleukin 1β) treatment of WT MVEC induced significant barrier dysfunction (by all three methods), and was associated with a time-dependent decrease in TIMP3 mRNA and protein levels. Additionally, basal Timp3(-/-) MVEC barrier dysfunction was associated with disrupted MVEC surface VE-cadherin localization, and both barrier dysfunction and VE-cadherin localization were rescued by treatment with GM6001, a synthetic metalloproteinase inhibitor. TIMP3 promotes normal MVEC barrier function, at least partially, through inhibition of metalloproteinase-dependent disruption of adherens junctions, and septic downregulation of TIMP3 may contribute to septic MVEC barrier dysfunction.

Keywords: sepsis; tissue inhibitor of metalloproteinases; vascular leak.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adherens Junctions / metabolism
  • Animals
  • Antigens, CD / metabolism
  • Cadherins / metabolism
  • Capillary Permeability* / drug effects
  • Cells, Cultured
  • Cytokines / pharmacology
  • Dipeptides / pharmacology
  • Disease Models, Animal
  • Endothelial Cells / metabolism*
  • Genotype
  • Lung / blood supply*
  • Male
  • Matrix Metalloproteinase Inhibitors / pharmacology
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Microvessels / drug effects
  • Microvessels / metabolism*
  • Microvessels / physiopathology
  • Phenotype
  • Pulmonary Edema / genetics
  • Pulmonary Edema / metabolism*
  • Pulmonary Edema / physiopathology
  • Sepsis / genetics
  • Sepsis / metabolism*
  • Sepsis / physiopathology
  • Time Factors
  • Tissue Inhibitor of Metalloproteinase-3 / deficiency
  • Tissue Inhibitor of Metalloproteinase-3 / genetics
  • Tissue Inhibitor of Metalloproteinase-3 / metabolism*


  • Antigens, CD
  • Cadherins
  • Cytokines
  • Dipeptides
  • Matrix Metalloproteinase Inhibitors
  • N-(2(R)-2-(hydroxamidocarbonylmethyl)-4-methylpentanoyl)-L-tryptophan methylamide
  • Tissue Inhibitor of Metalloproteinase-3
  • cadherin 5