ABSTRACT
Three lichen extracts and ten lichenic compounds have been screened for their photoprotective activities. The determination of their Sun Protection Factor (SPF) and Protection Factor-UVA (PF-UVA) values was done in vitro. Among them, a Lasallia pustulata extract and gyrophoric acid exhibited SPF values over 5, which is better than Homosalate (SPF≈4). Their photoprotective properties are only slightly modified after a 2-hours period of irradiation. Salazinic acid and L. pustulata presented characteristics of a UVA booster like the butyl-methoxydibenzoylmethane (Avobenzone) (PF-UVA≈2 vs. 2.8 for Avobenzone). Salazinic acid was a better anion superoxide scavenger than ascorbic acid and none of them exhibited a photosensitizing cytotoxicity by exposing them on HaCaT cells to UVA radiations (photo-irritancy factor PIF<5).
Subject(s)
Sun Protection Factor/methods , Ultraviolet Rays , Usnea/chemistry , Usnea/metabolism , Antioxidants/isolation & purification , Antioxidants/metabolism , Antioxidants/pharmacology , Antioxidants/toxicity , Ascomycota/chemistry , Ascomycota/metabolism , Benzoates/isolation & purification , Benzoates/metabolism , Benzoates/pharmacology , Benzoates/toxicity , Benzofurans/isolation & purification , Benzofurans/metabolism , Benzofurans/pharmacology , Benzofurans/toxicity , Cell Line , Fumarates/isolation & purification , Fumarates/metabolism , Fumarates/pharmacology , Fumarates/toxicity , Humans , Lactones/isolation & purification , Lactones/metabolism , Lactones/pharmacology , Lactones/toxicity , Salicylates/isolation & purification , Salicylates/metabolism , Salicylates/pharmacology , Salicylates/toxicityABSTRACT
The effect of dosing vehicle on toxicity and metabolism of unsaturated aliphatic nitriles was investigated in male Sprague-Dawley rats. Five unsaturated aliphatic nitriles--acrylonitrile, methacrylonitrile, allylnitrile, crotononitrile and fumaronitrile--were prepared in five different dosing vehicles--saline, corn oil, safflower oil, mineral oil, olive oil and Tween-20. Groups of six male rats were given 0.5 LD50 doses of the nitriles by gavage and they were observed for 12 It for cholinomimetic and central nervous system effects. Cyanide and glutathione levels were determined in blood and various organs at 1, 3 and 6 h after nitrile administration and thiocyanate levels were determined at 6 h after nitrile administration. The results indicate that all the vehicles studied potentiated the toxicity of all the nitriles compared to nitriles administered in saline and significantly increased their metabolism to cyanide and thiocyanate and nitrile-induced depletion of glutathione in rats. This behavior of vehicles illustrates the difficulty of identifying suitable vehicles for administration of lipophilic compounds in toxicology studies.