A review of alternative methods to the use of animals in safety evaluation of cosmetics

ABSTRACT Alternative methods to the use of animals in research have been a global trend, mainly after the publication of the 3R's principle (Replacement, Reduction, and Refinement), proposed by Russel and Burch. In the cosmetic sector, safety and efficacy assessments using animals have generated controversial debates. For this reason, in vitro research techniques are widely used to assess acute toxicity; corrosivity and irritation; skin sensitization; dermal and percutaneous absorption; repeated dose toxicity; reproductive toxicity; mutagenicity and genotoxicity; carcinogenicity; toxicokinetic studies; photo-induced toxicity; and human data. Although there are many methodologies described, validated, and widely used in the cosmetic area, the evaluation of the safety of cosmetic ingredients and products is still an expanding field. It needs global collaboration among regulatory agencies, universities, and industry, to meet several unmet needs in the fields of sensitization, carcinogenicity, systemic action, among other issues involving safety of users of cosmetic products. This review article will cover the currently most relevant in vitro models regarding irritation, corrosion, sensitization, mutagenicity, genotoxicity, and phototoxicity, to help to choose the most appropriate test for evaluating the safety and toxicity of cosmetic ingredients and products.

Reducción del colesterol y aumento de la capacidad antioxidante por el consumo crónico de maíz morado (zea mays L) en ratas hipercolesterolémicas / Cholesterol reduction and increase of antioxidant capacity by chronic consupmtion of andean purle corn (zea mays L) in hypercholesterolemic rats

Objetivos: Determinar la actividad hipocolesterolémica y antioxidante del consumo crónico del extracto hidroalcohólico atomizado del maíz morado (Zea mays L) en ratas hipercolesterolémicas. Materiales y métodos: Se utilizaron cincogrupos de seis ratas Holtzmann cada uno, uno sin hipercolesterolemia (control negativo), y cuatro con hipercolesterolemia inducida por consumo de colesterol puro vía oral durante 60 días: control positivo y tres para las dosis de 250, 500 y 1000 mg/kg, respectivamente. En el día 60 se determinaron los niveles séricos de colesterol total, triglicéridos ycolesterol HDL (mg/dL), así como de malondialdehido (mmol/L) para determinar la actividad antioxidante. Se comparó la diferencias de medias con ANOVA y test de Tukey. Resultados: Se observó una disminución del colesterol total en las ratas hipercolesterolémicas que consumieron dosis de 250 y 500 mg/kg en relación con el grupo control positivo (reducción de 21,5 y 11,2 por ciento respectivamente, p menor que 0,01). No se observaron diferencias significativas sobre los niveles de triglicéridos y colesterol HDL. A mayor dosis se maíz morado se encontró una mayor reducción de radicales libres, conla dosis de 1000 mg/kg se redujo en 56,4 por ciento los niveles de malondialdehido (p menor que menor que 0,01). Conclusiones: En condiciones experimentales, el consumo crónico del extracto hidroalcohólico atomizado de maíz morado disminuye los niveles decolesterol total y aumenta la capacidad antioxidante.

Objetives: To determine the hypocholesterolemic antioxidant activity of the Andean purple corn (Zea mays L)hydroalcoholic extract atomized chronic consumption in hypercholesterolemic rats. Material and methods: Five groupsof six Holtzmann rats each were used, one without hypercholesterolemia (negative control), and four with inducedhypercholesterolemia by oral intake of pure cholesterol by 60 days: positive control and three for doses of 250, 500 y1000 mg/kg, respectively. In 60 day were determin the seric levels of total cholesterol, triglycerides and HDL cholesterol (mg/dL), as well as malondialdehyde (mmol/L) to determine the antioxidant activity. We compared the mean differneceswith ANOVA and Tukey test. Results: We observed a decrease in total cholesterol in hypercholesterolemic rats thatconsumed Andean purple corn doses of 250 and 500 mg/kg in compared whit positive control group (reduction of 21,5y 11,2 percentage respectively, pminor than 0,01). No significant differences in levels of triglycerides and HDL cholesterol were observed. A higher dose is purple corn was a further reduction of free radicals, with a dose of 1000 mg/kg decreased by 56.4 porcentage, levels of malondialdehyde (p minor than 0,01). Conclusions: In experimental conditions, the chronic consumption of the hydroalcoholic atomized extract of Andean purple corn decreased total cholesterol and increased the antioxidant capacity.