The occurrence of 5α‐cholestan‐3β‐ol (Dihydrocholesterol) in human skin surface lipid

Nicolaides, Nicholas C.; Nair, Padmanabhan P.; deLeon, Stella

doi:10.1007/bf02531290

Cited by 3 publications

(2 citation statements)

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“…The present study does not lead us to conclude, however, that the Kandutsch-Russell pathway is the only biosynthetic pathway present in the human skin. The presence of trace quantities of dihydrocholesterol and 7-dehydrocholesterol has been reported previously in the skin surface lipids of man (35,36). The presence of the former has recently been shown by using a combination of silver ion-TLC and GLC methods (35), whereas the latter's presence was shown by ultraviolet absorption spectrum of the digi- The daily loss of cholesterol from the skin surface was 1/4 to 1/6 of the daily total fecal neutral steroid excretion in man (2)(3)(4)(5).…”

Section: Methodssupporting

confidence: 59%

“…Each subject was given intravenously [35][36][37][38][39][40] ,uCi of either cholesterol-4--4C or cholesterol-la-5H 1 dissolved in 5 ml ethanol and then suspended in 500 ml of 0.9% sodium chloride solution. In the course of the cholesterol turnover study, venous blood samples were drawn in the fasting state weekly or twice weekly for the next 9 or 10 wk.…”

Section: Methodsmentioning

confidence: 99%

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Excretion of sterols from the skin of normal and hypercholesterolemic humans

Bhattacharyya¹,

Connor²,

Spector³

1972

J. Clin. Invest.

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A B S T R A C T The 24 hr sterol excretion from the entire skin surface was determined in six normal and five hypercholesterolemic (Type II) patients fed a controlled, eucaloric diet containing 400 mg of plant sterols. All subjects received radiolabeled cholesterol intravenously in order to measure cholesterol turnover and exchange. The 24 hr skin surface lipids were collected subsequently at intervals of 7-10 days. Sterols were quantified and identified by a combination of thin-layer and gas-liquid chromatographic methods. The mean 24 hr excretion of cholesterol in milligrams was 82.6 in the normal subjects and 82.7 in the hypercholesterolemic patients. Cholesterol constituted 89% of the total sterol excretion through the skin surface in both groups.The specific radioactivity of cholesterol in the skin surface lipids increased gradually after the intravenous administration of the isotope. Within 4-5 wk the specific activity equaled and then remained higher than that of the plasma up to 10 wk. These specific activity curves suggested that, for at least some of skin surface cholesterol, there was a precursor-product relationship between the plasma cholesterol and the skin cholesterol.The presence of plant sterols, fi-sitosterol, campesterol, and stigmasterol in the skin surface lipids of man has not been reported previously. We identified these sterols in the skin surface lipids of all of our subjects. They constituted about 7% of the total skin surface sterols.This work was presented in part at

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Section: Methodssupporting

confidence: 59%

Section: Methodsmentioning

confidence: 99%

Excretion of sterols from the skin of normal and hypercholesterolemic humans

Bhattacharyya¹,

Connor²,

Spector³

1972

J. Clin. Invest.

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Gas chromatography of the fat‐soluble vitamins: A review

Sheppard

Prosser

Hubbard

1972

J Americ Oil Chem Soc

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The application of gas liquid chromatography (GLC) as an analytical tool for the determination of the fat-soluble vitamins A, D, E and K has yet to be utilized to its full potential. A review of the published work of many researchers in this field is presented. GLC methods to measure the vitamin A isomers have not been developed to any appreciable practical extent. Liquid liquid chromatography might well be the technique of choice. In the field of vitamin D there are indications that a practical GLC analysis is feasible for pharmaceutical preparations. The GLC applications for vitamin E are diverse, well defined and generally widely accepted in research laboratory situations and for regulatory and quality control usage. Vitamins K 1 and K 2 have been measured with limited success in a few research laboratories, but the GLC methods have not developed on a practical basis. However GLC is used for measuring vitamin K 3 (menadione and menadione sodium bisulfite) on a fairly routine basis in quality control laboratories.

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