CD36 mediates H2O2-induced calcium influx in lung microvascular endothelial cells

Am J Physiol Lung Cell Mol Physiol. 2017 Jan 1;312(1):L143-L153. doi: 10.1152/ajplung.00361.2016. Epub 2016 Dec 2.


Elevated levels of reactive oxygen species and intracellular Ca2+ play a key role in endothelial barrier dysfunction in acute lung injury. We previously showed that H2O2-induced increases in intracellular calcium concentrations ([Ca2+]i) in lung microvascular endothelial cells (LMVECs) involve the membrane Ca2+ channel, transient receptor potential vanilloid-4 (TRPV4) and that inhibiting this channel attenuated H2O2-induced barrier disruption in vitro. We also showed that phosphorylation of TRPV4 by the Src family kinase, Fyn, contributes to H2O2-induced Ca2+ influx in LMVEC. In endothelial cells, Fyn is tethered to the cell membrane by CD36, a fatty acid transporter. In this study, we assessed the effect of genetic loss or pharmacological inhibition of CD36 on Ca2+ responses to H2O2 H2O2-induced Ca2+ influx was attenuated in LMVEC isolated from mice lacking CD36 (CD36-/-). TRPV4 expression and function was unchanged in LMVEC isolated from wild-type (WT) and CD36-/- mice, as well as mice with deficiency for Fyn (Fyn-/-). TRPV4 immunoprecipitated with Fyn, but this interaction was decreased in CD36-/- LMVEC. The amount of phosphorylated TRPV4 was decreased in LMVEC from CD36-/- mice compared with WT controls. Loss of CD36 altered subcellular localization of Fyn, while inhibition of CD36 fatty acid transport with succinimidyl oleate did not attenuate H2O2-induced Ca2+ influx. Lastly, we found that CD36-/- mice were protected from ischemia-reperfusion injury in vivo. In conclusion, our data suggest that CD36 plays an important role in H2O2-mediated lung injury and that the mechanism may involve CD36-dependent scaffolding of Fyn to the cell membrane to facilitate TRPV4 phosphorylation.

Keywords: ROS; acute lung injury; calcium.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • CD36 Antigens / metabolism*
  • Calcium / metabolism*
  • Endothelial Cells / drug effects
  • Endothelial Cells / metabolism*
  • Fatty Acids / metabolism
  • Gene Deletion
  • Hydrogen Peroxide / pharmacology*
  • Lipoproteins, LDL / pharmacology
  • Lung / blood supply*
  • Mice, Inbred C57BL
  • Microvessels / cytology*
  • Oleic Acid / pharmacology
  • Phosphorylation / drug effects
  • Protein Binding / drug effects
  • Protein Transport / drug effects
  • Proto-Oncogene Proteins c-fyn / metabolism
  • Reperfusion Injury / metabolism
  • Reperfusion Injury / pathology
  • Subcellular Fractions / drug effects
  • Subcellular Fractions / metabolism
  • TRPV Cation Channels / metabolism


  • CD36 Antigens
  • Fatty Acids
  • Lipoproteins, LDL
  • TRPV Cation Channels
  • Trpv4 protein, mouse
  • acetyl-LDL
  • Oleic Acid
  • Hydrogen Peroxide
  • Fyn protein, mouse
  • Proto-Oncogene Proteins c-fyn
  • Calcium