Modulation of the cell kinetics of pig skin by the topical application of evening primrose oil or Lioxasol

Abstract

The daily topical application of two compounds, a cream containing 10% evening primrose oil (EPO) and Lioxasol (a compound used clinically to treat radiation burns), resulted in increased cell proliferative activity in the skin of female Large White pigs. The effect was most pronounced in the case of the EPO based cream, and was comparable in magnitude with that observed in a previous study on pig skin using orally administered EPO. There was an increase in the size of the rete pegs in the epidermis by 6 weeks after the start of application of the EPO cream. However, this did not translate into an increase in the total thickness of the viable epidermis (excluding the stratum corneum) due to a reduction in the density of rete pegs, from 2 weeks after treatment. Lioxasol had no overall effect on the size of the rete pegs. The labelling index (LI) of cells in the basal layer of the epidermis of pigs receiving a daily topical application of EPO increased progressively with time from the start of application. The LI was maximal (17.9 +/- 2.4%) at the end of the observation period (8 weeks) at which time it was a factor of approximately 2 higher than in the basal layer prior to treatment. A considerably less marked increase in the LI of the basal layer was seen after the application of Lioxasol. The overall increase was approximately 20%, relative to the LI in the untreated epidermis. Labelled cell nuclei were also counted in the papillary dermis. After the application of the EPO cream, no significant increase in the number of labelled cells was observed until week 8, at which time values were approximately twice those in untreated skin. In Lioxasol treated skin the effect on the numbers of labelled cells in the papillary dermis was more immediate, with a approximately 60% increase at 2 weeks. This enhanced level of labelling was maintained until the end of the observation period of 10 weeks. Studies on the cell kinetics of the skin using the alcohol component of the Lioxasol preparation suggested that alcohol rather than Lioxasol was the most significant ingredient. It was concluded that the EPO cream merited further evaluation as a potential modulator of skin response to ionizing radiation.

Moist Skin Care Can Diminish Acute Radiation-Induced Skin Toxicity

“…Dry skin care is, so far, most often applied, because it is easy to handle [23]. Nevertheless, according to experimental and clinical data published recently, moist skin care may diminish radiation-induced skin toxicity [10][11][12][13][14][15]. We wanted to investigate, whether a waterbinding urea lotion will decrease acute radiation-induced skin reactions as well.…”

Models for Evaluating Agents Intended for the Prophylaxis, Mitigation and Treatment of Radiation Injuries Report of an NCI Workshop, December 3–4, 2003

“…Extensive desquamation is a major management issue requiring fluids, antibiotics and, where necessary, skin grafts. Topical application of evening primrose oil and other polyunsaturated fatty acids has been found to modulate cell proliferation in pig skin and to be beneficial in the case of radiation injury to the skin (167) and mucosa (168). Application of an emulsion containing trolamine affected the response of human skin cultures to radiation (165).…”

The Composition and Development of Moisturizers

“…The role of essential fatty acids may be more fundamental than modifi cation of stratum corneum properties. Effects on cell proliferation [ 76 ] , wound healing [ 77 ] and complementary cancer care [ 78 ] whilst outside the remit of this chapter offer potential for future applications of moisturizers.…”