PubMed Health⌕ Search

Biomedical subjects

V B Smart

Publications and source records attributed to V B Smart.

5 recordsLinked to original sources
PubMed1986

Mutagenic sterol hydroperoxides.

Sterol hydroperoxides 3 beta-hydroxy-5 alpha-cholest-6-ene-5-hydroperoxide and 3 beta-hydroxycholest-5-ene-7 alpha-hydroperoxide show weak dose-response direct mutagenicity towards Salmonella typhimurium strain TA 1537 in a liquid medium incubation bioassay. Responses were compromised by metabolism of the sterol hydroperoxides and by phase separation during the incubation period. Mutagenicity responses were increased by added superoxide dismutase but diminished by added rat liver S9 enzymes and abolished by added catalase. Catalase also abolished the stimulatory effect of superoxide dismutase. These results indicate that superoxide and peroxide be implicated in the mutagenicity responses.

Animals↗
PubMed1982

Further investigations of mutagenic cholesterol preparations.

The previously demonstrated mutagenicity of naturally air-aged (autoxidized) USP cholesterol in test strains of Salmonella typhimurium has been confirmed. In contrast, autoxidized brassicasterol, 7-dehydrocholesterol, ergosterol, lanosterol, sitosterol, and stigmasterol were non-mutagenic in the same assay, and 38 individual cholesterol derivatives, including many cholesterol autoxidation products, were also non-mutagenic. The mutagenic species from mutagenic cholesterol preparations were shown to be neutral steroids that are very much more polar than the cholesterol autoxidation products so far identified. High-performance liquid chromatography resolved mutagenic cholesterol preparations into several mutagenic and non-mutagenic fractions. The chemical nature of the mutagens is suggested as involving oxidation of the sterol B-ring and of the side-chain.

Cholesterol↗
PubMed1979

Mutagenic cholesterol preparations.

Naturally air-aged commercial samples of USP or reagent-grade cholesterol contain components which are mutagenic towards Salmonella typhimurium strains TA1537, TA1538 and TA98. These mutagenic components are associated with the polar cholesterol autoxidation products, but identity of the mutagenic components has not been achieved. Pure crystalline nonmutagenic cholestrol free from autoxidation products becomes mutagenic towards these strains upon heating at 70 degrees in air or following exposure to 60 Co gamma-radiation.

Cholesterol↗