Investigation of cytotoxicity and skin-sensitizing potential of Asarum radix oil using LLNA:BrdU-ELISA

Abstract

Asarum radix extract is commonly used in cosmetic products. Cytotoxicity testing and an ex vivo local lymph node 5-bromo-2-deoxyuridine (LLNA-BrdU) assays were performed to determine the dermal sensitization potential of A. radix extracts. The cytotoxicity assay indicated inhibitory effects on cell viability in a human forearm skin fibroblast cell line after 24-h incubation at concentrations of A. radix extract above 0.075 mg/mL. To assess skin sensitization, A. radix extracts (10%, 25%, and 50% v/v) were applied to the ears (dorsal surface) of female CBA mice. Changes in clinical signs, body weight, skin reactions, ear thickness, skin stimulation index (SI), and mortality were evaluated. After 6 days, no changes in treatment-related clinical signs, skin reactions, erythema, body weight, or mortality were observed in any treatment group. The results of the ex vivo LLNA-BrdU assays yielded a moderate SI of 3.09%. For the 10%, 25%, and 50% (v/v) treatment groups, SIs were calculated as 0.9, 1.2, and 2.1, respectively. Thus, at concentrations below 25% (v/v), A. radix oil was not skin sensitizing.