Non-muscular myosin light chain kinase triggers intermittent hypoxia-induced interleukin-6 release, endothelial dysfunction and permeability

Sci Rep. 2017 Oct 20;7(1):13664. doi: 10.1038/s41598-017-13268-5.

Abstract

Obstructive sleep apnea is characterized by intermittent hypoxia (IH) which alters endothelial function, induces inflammation and accelerates atherosclerosis-induced cardiovascular diseases. The non-muscular myosin light chain kinase (nmMLCK) isoform contributes to endothelial cell-cell junction opening. Deletion of nmMLCK protects mice from death in septic shock models and prevents atherosclerosis in high-fat diet-fed mice. The aim of the study was to analyze the implication of nmMLCK in IH-induced vascular inflammation. Human aortic endothelial cells were exposed to 6 hours of IH in absence or presence of nmMLCK inhibitors, ML-7 (5 µM) or PIK (150 µM). IH increased reactive oxygen species (ROS) and nitric oxide (NO) production, p65-NFκB activation and IL-6 secretion. While nmMLCK inhibition did not prevent IH-induced ROS production and p65-NFκB activation, it decreased NO production and partially prevented IL-6 secretion. IH-induced IL-6 secretion and vesicle-associated membrane protein-associated vesicles re-organization were inhibited in presence of the inhibitor of protein secretion, brefeldin A, or ML-7. IH increased monocytes transendothelial migration that was partially prevented by ML-7. Finally, IH reduced endothelium-dependent relaxation to acetylcholine of aortas from wild-type but not those taken from nmMLCK-deficient mice. These results suggest that nmMLCK participates to IH-induced endothelial dysfunction resulting from cytokines secretion and endothelial permeability.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Aorta / drug effects
  • Aorta / enzymology*
  • Aorta / pathology
  • Atherosclerosis / enzymology
  • Atherosclerosis / pathology
  • Capillary Permeability / drug effects
  • Capillary Permeability / physiology*
  • Cell Adhesion / physiology
  • Cell Hypoxia / drug effects
  • Cell Hypoxia / physiology*
  • Cell Movement / physiology
  • Cells, Cultured
  • Coculture Techniques
  • Disease Models, Animal
  • Endothelial Cells / drug effects
  • Endothelial Cells / enzymology*
  • Endothelial Cells / pathology
  • Humans
  • Interleukin-6 / metabolism*
  • Mice, Knockout
  • Myosin-Light-Chain Kinase / deficiency
  • Myosin-Light-Chain Kinase / genetics
  • Myosin-Light-Chain Kinase / metabolism*
  • Reactive Oxygen Species / metabolism
  • Secretory Vesicles / drug effects
  • Secretory Vesicles / enzymology
  • Secretory Vesicles / pathology
  • Sleep Apnea, Obstructive / enzymology
  • Transcription Factor RelA / metabolism

Substances

  • IL6 protein, human
  • Interleukin-6
  • Reactive Oxygen Species
  • Transcription Factor RelA
  • interleukin-6, mouse
  • Myosin-Light-Chain Kinase
  • non-muscle myosin light-chain kinase, human
  • non-muscle myosin light-chain kinase, mouse