Effects of Neutral Shampoos on Cultures of Human Fibroblasts

Abstract

Criteria used to predict the effect of neutral shampoos on fibroblast cultures were based on assays which were easy to perform, reproducible and adaptable to a large number of substances. The tests were based on the determination of the integrity of the plasma membrane, the rate of protein synthesis, and cell viability.

Six different shampoos were tested: four were of the best quality commercially available, while the other two were new compounds. The substances were tested over a wide concentration range and were applied to human fibroblast cultures for various exposure times. Lactate dehydrogenase release into the medium was used as a marker of plasma membrane integrity, the amount of [³H]-labelled protein in the fibroblasts was measured to assess the function of the cell biosynthetic machinery, and the number of damaged cells which did not take up the neutral red dye showed the percentage of cytolysis.

The results indicated significant differences between the six shampoos, and a relationship between the biochemical parameters was found. This suggests that these tests on cell functionality may represent reliable markers for monitoring the cellular target damaged by xenobiotic compounds.