Los métodos alternativos en el estudio de la seguridad de cosméticos / Alternative methods in the study of the safety of cosmetics

El Reglamento 1223/2009 establece las normas que deben cumplir todos los productos cosméticos comercializados en Europa, con objeto de velar por el funcionamiento del mercado interior y lograr un elevado nivel de protección de la salud humana garantizando el uso de métodos alternativos que no impliquen la utilización de animales. El Laboratorio Europeo de Referencia para las Alternativas a la Experimentación con Animales (EURL-EURL- ECVAM) es el laboratorio de referencia en Europa encargado de validar los métodos alternativos. Posteriormente pueden ser homologados por la Organización de Cooperación y Desarrollo Económico (OCDE). Por otro lado, el Comité Científico de Seguridad de los Consumidores (SCCS) asesora a la Comisión sobre todos los temas relacionados con la seguridad de los cosméticos. En esta revisión se detalla una relación de métodos alternativos necesarios para evaluar la seguridad de los ingredientes cosméticos así como los métodos usados y sus limitaciones (AU)

Regulation 1223/2009 apply to all cosmetic products marketed in Europe in order to ensure the internal market and achieve a high level of protection of human health by ensuring the use of alternative methods not involving the use of animals. The European Reference Laboratory for Alternatives to Animal Testing (EURL- EURL-ECVAM) is the European reference laboratory responsible for validating alternative methods. They can also be approved by the Organization for Economic Cooperation and Development (OECD). In addition, the Scientific Committee on Consumer Safety (SCCS) advises the EU Commission on all issues related to cosmetic safety. In this review, alternative methods needed to assess the safety of cosmetic ingredients and the methods used and their limitations are outlined (AU)

A synthetic alternative to natural lecithins with antimicrobial properties.

Two soft biocompatible cationic surfactants from the amino acid arginine, 1,2-dilauroyl-3-acetylarginyl-rac-glycerol (1212RAc) and 1,2-dimirystoyl-3-acetylarginyl-rac-glycerol (1414RAc), were prepared. Their physicochemical properties show that they can be classified as multifunctional surfactants with self-aggregation behaviour comparable to that of short-chain lecithins. The two surfactants can simultaneously stabilise water-in-oil (W/O) droplets and oil-in-water (O/W) droplets, forming multiple emulsions. They have antimicrobial activity similar to that of conventional cationic surfactants and are as harmless as amphoteric betaines. These surfactants constitute an interesting alternative to the diglycerides and lecithins in formulations that require antimicrobial properties.

Interactions of surfactants with living cells. Induction of apoptosis by detergents containing a beta-lactam moiety.

The toxicity of new surfactants containing a beta-lactam ring has been established by studying their interaction with a hybridoma cell line. An hour of contact is sufficient to generate an apoptotic signal after two days of culture. Under the experimental conditions chosen for the experiments, surfactants have been divided into three categories: i) biocompatible and non-apogenic; ii) surfactants triggering an apoptotic signal without inducing cell necrosis; iii) surfactants triggering an apoptotic signal at low concentrations and destroying the cells by necrosis at higher concentrations. The necrosis inducing surfactants also had haemolytic properties. These properties were related to the values of the hydrophilic-lipophilic balance of the molecules.

Preparation and antibiotic activity of monobactam analogues of nocardicins.

A series of diverse beta-lactam analogues of nocardicins with interesting antimicrobial properties were prepared. Coupling of glucosamine to these compounds improved their water solubility. Aminoacid derivatives produced a stereoinduction on the quaternary enantiotopic carbon of the starting compound 1. Evaluation of their antimicrobial activity showed that the introduction of alpha-amninoacids to monobactams increased their activity. The importance of asymmetric carbon is exemplified by the higher antibiotic activity of L-alpha-aminoacids than the D-series. No significant difference was observed between fluorinated and non-fluorinated monobactams.

Age dependent changes on jejunal sugar absorption by rat in vivo.

Jejunal absorption of D-Glucose, D-Galactose and L-Arabinose was studied in 21-23 day, 2-3 month and 18 month-old rats for 5 minute periods using a perfusion technique. Sugar concentrations were: 2.5, 5, 10, 20 and 40 mM at each age. In some experiments phlorizin was used to determine the diffusional component of absorption. The saturation for D-Glucose was at 10 mM and 5 mM for D-Galactose. A reduction in the rate of total sugar absorption was observed with aging. Moreover, the active transport/simple diffusion ratio also decreases with age, specially at low substrate concentrations.