Defensive Effects of Fullerene-C60 Dissolved in Squalane Against the 2,4-Nonadienal-Induced Cell Injury in Human Skin Keratinocytes HaCaT and Wrinkle Formation in 3D-Human Skin Tissue Model

摘要

We dissolved fullerene-C60 in squalane (LipoFullerene; LF-SQ, C60-eq.: 500 ppm) and exam-ined its defensive effects against 2,4-nonadienal (NDA)-induced cell injury in HaCaT keratinocytesand wrinkle formation in three dimensional (3D)-human skin tissue model. NDA is an analog of4-hydroxynonenal, one of major causes for human body odor indicative of aging and a lipophilic cellinjury factor. Cell viability (3/0 of the control) decreased to 31.6% on treatment with NDA (40 AM),but it increased to 66.0-97.5% when LF-SQ of 1-4% (C60-eq.: 5-20 ppm) was administered for5 hr before NDA addition. The defensive effect by LF-SQ was superior to that of "squalane" aloneat the same doses. NDA-induced DNA-fragmentation in HaOaT cells was suppressed by LF-SQadministered for 5 hr before NDA treatment, and LF-SQ protected HaCaT cells against apoptosis-like cell death. LF-SQ did not appreciably defend against hydrogen peroxide, though LF-SQ effec-tively defended against tert-butylhydroperoxide, a type of the intermediate hydrophilicity–lipophilicitydegree out of other reactive oxygen species. The scanning electron microscopy demonstrated thatNDA caused wrinkles and abnormal scales on keratinocytes of 3D-human skin tissue model, andstructural homogeneity of the interstratum was broken, any of which were, however, markedly sup-pressed with LF-SQ. Squalane alone exhibited defensive effect against the skin tissue injury tosome extent, but which was inferior to LF-SQ. LF-SQ might effectively capture and scavenge lipidradicals generated inside the cell membrane, because squalane acts as a lipophilic carrier of C60.C60 dissolved in squalane can be expected to serve as a cosmeceutical ingredient for anti-wrinkleformation.