Connective tissue responses to oxysterols.

We studied the effect of sterols and oxidized sterols on promoting tissue inflammation and necrosis, and on causing cell death in tissue culture. The cells studied were mouse fibroblasts and macrophages, and pig vascular smooth muscle. The lipid preparations were dibromide-purified cholesterol, air-oxidized cholesterol, 25-hydroxycholesterol, cholesterol-5alpha, 6 beta-epoxide and cholestane 3 beta, 5 alpha, 6 beta-triol. Of these, the triol was most active in its cytopathic effect on cells in culture, in size of granuloma formation and in producing necrosis. The epoxide, 25-hydroxycholesterol and air-oxidized cholesterol produced rather less effect on tissues and cultures than the triol, but more than purified cholesterol and the control. The results are considered in relation to the presence of oxysterols in stored foodstuffs and their possible presence over the surface of cholesterol crystals in the tissues.