Dolfini, E., M. Lavazza, and M. Meloni. Cytotoxicity and Antiaging Activity of Some Cosmetic Compounds: A Pool of In Vitro Tests on Two Human Immortalized Cell Lines, NCTC 2544 and WI-38. In Vitro Toxicol. 1997. 10(1): 55-61.

hyaluronic acid - 09004-61-9; ceramide - 104404-17-3

This research presents an in vitro model in a pool of tests to study some biological activities on two human immortalized cell lines: keratinocytes (NCTC 2544) and fibroblasts (WI 38). The tests were set up to analyze the cytotoxicity, efficacy, cytoskeleton protein alterations, and the prolongment on in vitro cell life of hyaluronic acid, ceramides, and two patented active anti-free radical cosmetic substances: Plusina and its lipophilic derivative, Plusina 2000.

The nontoxic dose of each compound was chosen to study the biological alterations of some growth parameters.

In the serum-free assay, calf serum was substituted in culture medium for the nontoxic dose of each compound. The highest activity on the cellular growth was shown by the ceramides (two cellular doublings more compared to the untreated controls).

Our studies on the cytoskeleton protein structure showed degradation and partial depolymerization of cytokeratin 18 on NCTC 2544 cell line after treatment with Plusina and Plusina 2000 (10 ug/ml). The aging test on human fibroblasts WI 38 showed that only Plusina 2000 induced long extension of cellular life span of 70 days compared to untreated controls. From our data it seems that these tests could be of interest for a preliminary in vitro study of toxicology, efficacy, and prolongment of in vitro cell life of a large amount of raw materials and cosmetic active substances as a possible alternative to animal testing.