Nitric oxide regulates tissue transglutaminase localization and function in the vasculature

Simran K. Jandu, Alanah K. Webb, Alina Pak, Baris Sevinc, Daniel Nyhan, Alexey M. Belkin, Nicholas A. Flavahan, Dan E Berkowitz, Lakshmi Santhanam

Research output: Contribution to journalArticlepeer-review

19 Scopus citations


The multifunctional enzyme tissue transglutaminase (TG2) contributes to the development and progression of several cardiovascular diseases. Extracellular rather than intracellular TG2 is enzymatically active, however, the mechanism by which it is exported out of the cell remains unknown. Nitric oxide (NO) is shown to constrain TG2 externalization in endothelial and fibroblast cells. Here, we examined the role of both exogenous and endogenous (endothelial cell-derived) NO in regulating TG2 localization in vascular cells and tissue. NO synthase inhibition in endothelial cells (ECs) using N-nitro l-arginine methyl ester (l-NAME) led to a time-dependent decrease in S-nitrosation and increase in externalization of TG2. Laminar shear stress led to decreased extracellular TG2 in ECs. S-nitrosoglutathione treatment led to decreased activity and externalization of TG2 in human aortic smooth muscle and fibroblast (IMR90) cells. Co-culture of these cells with ECs resulted in increased S-nitrosation and decreased externalization and activity of TG2, which was reversed by l-NAME. Aged Fischer 344 rats had higher tissue scaffold-associated TG2 compared to young. NO regulates intracellular versus extracellular TG2 localization in vascular cells and tissue, likely via S-nitrosation. This in part, explains increased TG2 externalization and activity in aging aorta.

Original languageEnglish (US)
Pages (from-to)261-269
Number of pages9
JournalAmino Acids
Issue number1
StatePublished - Jan 2013


  • Aging
  • Nitric oxide
  • S-nitrosation
  • Tissue transglutaminase

ASJC Scopus subject areas

  • Biochemistry
  • Organic Chemistry
  • Clinical Biochemistry


Dive into the research topics of 'Nitric oxide regulates tissue transglutaminase localization and function in the vasculature'. Together they form a unique fingerprint.

Cite this