Cholesterol Epoxidations by Defined Oxygen Species
Part of the
Basic Life Sciences
book series (BLSC, volume 49)
Each defined species of active oxygen implicated in oxygen biochemistry, with the exception of superoxide (· O2 -, HOO ·), is known to oxidize cholesterol under conditions potentially present in vivo. Oxysterols found in tissues thus may have at least two origins, enzymic ones related to in vivo metabolism (including lipid peroxidation) and nonenzymic origins in which active oxygen species hydroxyl radical (HO), dioxygen cation (O2 +) singlet dioxygen (1O2), ground state dioxygen (3O2), peroxide (O2 2-, HOO-, H2O2) ozone (O3), and as yet unrecognized species may be implicated. As the oxysterols formed in all cases have demonstrated biological activities in a variety of bioassays, the question must be posed whether such oxysterols, if formed in. vivo and not properly controlled by protective metabolism, are a threat to human health.
KeywordsSteryl Ester Cumene Hydroperoxide Carbonyl Oxide Cholesterol Oxide Carbon Nuclear Magnetic Resonance
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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