Studies of sebum. VIII. Observations on the squalene and cholesterol content and the possible functions of squalene in human sebum.

Studies of sebum. IV. The estimation of squalene in sebum and sebum-like materials.

The possible role of squalene as a protective agent in sebum.

Human sebum contains squalene, which is a polyunsaturated triterpenoid hydrocarbon (2, 7). This substance constitutes approximately 5 per cent of skin surface sebum of the adult (2). Oxygen is taken up avidly when squalene is ex posed to air, with the rapid formation of peroxides. This fact suggested that it might function as a protective agent in sebum. It has been demon strated that it is fun...

Changes in skin surface lipid composition induced by severe caloric restriction in man.

Lipid collected from the surface of the human forehead is predominantly (-95%) the product of the sebaceous glands (1) and contains on the average 41 % triglycerides, 16.5% free fatty acids, 25% wax esters, 12% squalene, 1.5% cholesterol, 2% cholesterol esters, and 2% diglycerides (2). This sebum composition shows little variation between normal subjects or over long periods of time in individu...

Surface Lipids as Multifunctional Mediators of Skin Responses to Environmental Stimuli

Skin surface lipid (SSL) film is a mixture of sebum and keratinocyte membrane lipids, protecting skin from environment. Its composition is unique for the high percentage of long chain fatty acids, and of the polyterpenoid squalene, absent in other human tissues, and in non-human Primates sebum. Here, the still incomplete body of information on SSL as mediators of external chemical, physical, an...

Regional variations in density of cutaneous propionibacteria: correlation of Propionibacterium acnes populations with sebaceous secretion.

Cutaneous Propionibacterium acnes populations were quantitatively measured in 33 young adults and compared with the rate and composition of sebum secretion in nine skin regions. Bacteriological and lipid analyses were performed on the forehead, cheek, anterior chest, abdomen, lower back, volar forearm, upper inner arm, thigh, and calf. P. acnes populations in these sites correlated significantl...