Related Experiment Video
Updated: Aug 6, 2026
09:14
Static Adhesion Assay for the Study of Integrin Activation in T Lymphocytes
Published on: June 13, 2014
Telmisartan inhibits beta2-integrin MAC-1 expression in human T-lymphocytes
Andreas Link1, Monika Lenz, Dominik Legner
1Klinik für Innere Medizin III, Universität des Saarlandes, Homburg/Saar, Germany. link@med-in.uni-saarland.de
Journal of Hypertension
|August 18, 2006
Summary
Telmisartan, an AT1 receptor antagonist, reduces pro-inflammatory MAC-1 expression on lymphocytes. This effect occurs independently of angiotensin II, suggesting a novel atheroprotective mechanism.
Area of Science:
- Cardiovascular Medicine
- Immunology
- Pharmacology
Background:
- Atherosclerosis is a chronic inflammatory disease influenced by the renin-angiotensin system.
- Angiotensin II subtype 1 (AT1) receptor activation plays a key role in atherosclerosis pathogenesis.
- Mechanisms underlying the pro-inflammatory effects of angiotensin II and anti-inflammatory effects of AT1 receptor antagonists are not fully understood.
Purpose of the Study:
- To investigate the effects of the AT1 receptor antagonist telmisartan on inflammatory markers in patients with hypertension and coronary artery disease.
- To elucidate the in vitro mechanisms of telmisartan's action on lymphocyte inflammatory markers.
Main Methods:
- Prospective, double-blind study involving 42 patients (21 telmisartan, 21 placebo) treated for 12 weeks.
- Assessed inflammatory markers including hs-CRP, IL-6, s-ICAM-1, sL-selectin, and lymphocyte beta2 integrin MAC-1 expression.
- Conducted in vitro experiments using cultured human lymphocytes stimulated with angiotensin II or PMA/ionomycin, with or without telmisartan pretreatment.
Main Results:
- Telmisartan therapy significantly decreased lymphocyte beta2 integrin MAC-1 expression.
- No significant changes were observed in hs-CRP, IL-6, s-ICAM-1, or sL-selectin levels.
- In vitro, telmisartan inhibited beta2-integrin MAC-1 expression in lymphocytes independently of angiotensin II stimulation.
Conclusions:
- Telmisartan inhibits the pro-inflammatory beta2-integrin MAC-1 expression in lymphocytes via an AT1 receptor-independent pathway.
- This suggests a potential atheroprotective effect of telmisartan independent of its direct action on the AT1 receptor.
- The findings provide new insights into the anti-inflammatory mechanisms of telmisartan in cardiovascular disease.
Related Concept Videos
01:17Intracellular Signaling Affects Focal Adhesions
Integrins act both as extracellular input receivers and as intracellular processing activators. As their name suggests, integrins are entirely integrated into the membrane structure. Their hydrophobic membrane-spanning regions interact with the phospholipid bilayer's hydrophobic region. These membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors. They activate intracellular response cascades when their effectors are bound and active.
Some...
Some...
01:15Activation of Integrins
Integrins bind ligands and transmit information from outside the cell to inside or vice-versa through an "outside-in signaling" or "inside-out signaling."
In "outside-in signaling," external factors in the extracellular space bind to exposed ligand binding sites on integrins. This causes the inactive protein to undergo a conformational change to become active. Integrins are often clustered on the cell membrane. Repetitive and regularly spaced ligand binding events provide an effective stimulus.
In "outside-in signaling," external factors in the extracellular space bind to exposed ligand binding sites on integrins. This causes the inactive protein to undergo a conformational change to become active. Integrins are often clustered on the cell membrane. Repetitive and regularly spaced ligand binding events provide an effective stimulus.