The modulation of radiation-induced damage to pig skin by essential fatty acids.
The ability of essential fatty acids (EFAs) to modulate radiation-induced normal tissue injury was assessed in pig skin. Female Large White pigs (approximately 25 Kg) received 3 ml/day orally of either an 'active' oil [So-1100, containing 9% gamma-linolenic acid (GLA)] or a 'placebo' oil (So-1129) for just 4 weeks before or for 4 weeks before and for 16 weeks after irradiation; localised irradiation of skin was with single doses of beta-rays from 22.5 mm diameter 90Sr/90Y plaques. The severity of the acute reaction, assessed in terms of erythema or moist desquamation, was significantly less in those pigs that received So-1100 both before and after irradiation, as compared with those receiving that oil only prior to irradiation and the 'placebo' groups. Dose modification factors (DMFs) of between 1.13-1.24 were obtained. A similar reduction in the severity of acute skin injury was seen in pigs receiving So-1100 for only 10 weeks after irradiation. Late skin damage, assessed in terms of late erythema or dermal necrosis, was also reduced with So-1100, with DMFs of 1.14-1.51. No such modification was observed if So-1100 was only administered for 4 weeks prior to irradiation. No adverse side-effects were apparent as a result of EFA administration. So-1100 may represent a safe and valuable method of increasing the therapeutic gain in radiotherapy.
Research Institute (University of Oxford), Churchill Hospital, UK.
J W
JW
Hopewell
M E
ME
Robbins
G J
GJ
van den Aardweg
G M
GM
Morris
G A
GA
Ross
E
E
Whitehouse
D F
DF
Horrobin
C A
CA
Scott
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D001610:Beta Particles; D004307:Dose-Response Relationship, Radiation; D004890:Erythema / Q000517:prevention & control; D005228:Fatty Acids, Essential / Q000494:pharmacology*; D005260:Female; D008042:Linolenic Acids / Q000494:pharmacology*; D011833:Radiation Injuries, Experimental / Q000517:prevention & control*; D011837:Radiation-Protective Agents / Q000494:pharmacology*; D012867:Skin / Q000187:drug effects / Q000528:radiation effects*; D013324:Strontium; D013552:Swine; D015021:Yttrium Radioisotopes; D017965:gamma-Linolenic Acid
D000894:Anti-Inflammatory Agents, Non-Steroidal; D005228:Fatty Acids, Essential; D008042:Linolenic Acids; D011837:Radiation-Protective Agents; D015021:Yttrium Radioisotopes; D017965:gamma-Linolenic Acid; D013324:Strontium