Previous studies in other systems have shown that β-receptor blockers may effectively inhibit oxygen radical-induced lipid peroxidation. On the other hand, it has been recently proposed that oxygen free radicals can induce peroxidation of human low density lipoproteins (LDL), and that peroxidized LDL may be an atherogenic stimulus. Chemically modified LDL are internalized by macrophages via a specific cell surface receptor that was termed the scavenger receptor. This phenomenon may induce foam cells transformation in vivo. In the present study we investigated whether β-blockers may reduce oxygen radical-mediated LDL peroxidation. Purified human LDL were oxidized by exposure to oxygen free radicals generated by xanthine (0.2 mM) and xanthine oxidase (100 mU) at 37°C after a pre-incubation (30 min) in presence of different concentrations (from 1 to 30 μM) of acebutolol, metoprolol or propranolol, three agents with a different degree of lipophilicity. Peroxidation was measured from malonyldihaldehyde (MDA) production. Data have shown a significant percent inhibition of MDA formation in presence of β-blockers (from 33 to 85%). Thus, β-blockers reduced peroxidation of human LDL in vitro at clinically relevant concentrations. The order of potency appears to follow the degree of lipophilicity. These data suggest that, although β-blockers are known to adversely effect lipid metabolism, these agents might on the other hand prevent atherogenesis via a mechanism of inhibition of LDL peroxidation in vivo and reduced foam cells formation.
|Translated title of the contribution||Protection by β-blockers against oxygen radical-induced peroxidation of human low density lipoproteins|
|Number of pages||6|
|Journal||Giornale Italiano di Cardiologia|
|Publication status||Published - 1994|
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine