The effect of eicosa 5:8:11:14 tetraynoic acid on skin lipid synthesis ( 14 C incorporation) in vitro

The effect of 5,8,11,14-eicosatetraynoic acid on lipid metabolism

The purpose of this presentation is to review the current state of knowledge regarding 5,8,11,14-eicosatetraynoic acid (ETYA, Ro 3-1428) and its effects on lipid metabolism. Accordingly, the topics discussed include hypocholesterolemic and dermatological studies involving ETYA in both animals and man, as well as the effects of ETYA on desaturase enzymes. Metabolic studies involving ETYA are also noted. Primary interest is focused on the effects of ETYA on selected processes of arachidonate metabolism, and the effect of ETYA on inflammation, platelet aggregation and tumor growth are discussed, keeping in mind the relevance of arachidonate metabolism to these processes.

Effects of cyproterone acetate and carboxylic acid derivatives on the sebaceous glands of the Syrian hamster

The Syrian hamster ear model was used to study effects of the anti-androgen cyproterone acetate and of the anti-lipogenic compound 17beta-carboxylic acid methyl ester and its ethyl ester. The steroid derivatives were applied topically in a 1-2% concentration or given systemically. Response of sebaceous gland was measured by means of cell proliferation (3H-TdR autoradiography) and by gland size (histoplanimetry). Cyproterone acetate significantly reduced the labelling and the planimetric value, both topically and systemically. The carboxylic acid derivatives, which block the 5alpha-reductase were ineffective. The new animal model is a sensitive and suitable means to study inhibition of sebum production.

Incorporation of I-14C-acetate into the lipids of isolated epidermal cells

Suspensions of epidermal cells were prepared by trypsinization of rat epidermis and incubated with I-14C-acetate in Eagle's minimum essential medium. The incorporation of radioactivity into the total lipids of the cells was increased by the addition of serum to the medium. The pattern of incorporation into the main lipid classes was affected by the addition of serum to the medium and by alterations in the density of the cell suspensions. The incorporation of radioactivity into the total lipids increased approximately linearly over a 24-h period of incubation and the pattern of incorporation into the phospholipids and glycolipids altered with time. However, at each time interval studied, reporducible patterns of incorporation were obtained under controlled conditions. The incorporation of radioactive acetate therefore provides the basis for a very sensitive method of lipid analysis.