The invention relates to the use of quaternary pyridinium salts of formula (I), wherein R is NH2, CH3, or N(H)CH2OH group, and X is pharmaceutically acceptable counterion, for the preparation of vasoprotective agent for the treatment or prevention of conditions or diseases associated with dysfunction of vascular endothelium, oxidative stress, and/or insufficient production of endothelial prostacyclin PGI2, in particular but not exclusively if the above coincides with hypercholesterolemia, hypertriglyceridemia or low HDL level.