Synergistic effect of mechanical stretch and angiotensin II on superoxide production via NADPH oxidase in vascular smooth muscle cells

Hirofumi Hitomi, Toshiki Fukui, Kumiko Moriwaki, Keisuke Matsubara, Guang Ping Sun, Matlubur Rahman, Akira Nishiyama, Hideyasu Kiyomoto, Shoji Kimura, Koji Ohmori, Youichi Abe, Masakazu Kohno

Research output: Contribution to journalArticlepeer-review

37 Citations (Scopus)

Abstract

Objective: Mechanical forces and angiotensin II influence the structure and function of vascular cells, and play an important role in reactive oxygen species production. In this study, we examined the effects of mechanical stretch and angiotensin II on the expression of p22-phox and Nox-1, essential membrane components of NADPH oxidase, and superoxide production in rat vascular smooth muscle cells (VSMCs). Methods and results: Neither a stretch force nor angiotensin II alone altered p22-phox and Nox-1 expression in VSMCs. Combined stimulation markedly increased p22-phox and Nox-1 mRNA, however, which was associated with increased NADPH oxidase activity, superoxide production and total 8-iso-prostaglandin F2a concentration. The increases in p22-phox mRNA levels induced by a stretch force in combination with angiotensin II were prevented by treatment with an angiotensin type I (AT1) receptor antagonist, RNH-6270 (100 nmol/l). Protein expression of the AT1 receptor was upregulated by a stretch force. Conclusions: These data indicate that mechanical stretch and angiotensin II synergistically increase NADPH oxidase expression in VSMCs, and suggest that part of this mechanism is mediated through an upregulation of the AT1 receptor induced by mechanical stretch. The combined effects of mechanical strain and angiotensin II might promote vascular damage through the production of superoxide in a hypertensive state.

Original languageEnglish
Pages (from-to)1089-1095
Number of pages7
JournalJournal of hypertension
Volume24
Issue number6
DOIs
Publication statusPublished - 2006 Jun

Keywords

  • Angiotensin II
  • Mechanical stretch
  • NADPH oxidase
  • Reactive oxygen species
  • Vascular smooth muscle cells

ASJC Scopus subject areas

  • Internal Medicine
  • Physiology
  • Cardiology and Cardiovascular Medicine

Fingerprint Dive into the research topics of 'Synergistic effect of mechanical stretch and angiotensin II on superoxide production via NADPH oxidase in vascular smooth muscle cells'. Together they form a unique fingerprint.

Cite this