Hydrogen sulfide counteracts the main aspects of atherosclerosis such as oxidation, adhesion, proliferation and calcification by inhibiting: the increase of ROS and ox-LDL, the expression of ICAM-1, the migration of smooth muscle cells (SMC) from the medial to the sub-endothelial layer where they proliferate, incorporate ox-LDL and so contribute to the plaque development; and finally by inhibiting the expression of osteopontin gene and the increase of vessels calcium content and accumulation.