Antioxidant and cytoprotective effects of Stachys riederi var. japonica ethanol extract on UVA-irradiated human dermal fibroblasts

摘要

Stachys riederi is one of the largest genera in the flowering plant family Lamiaceae. The aqueous extract of Stachys riederi var. japonica is known for its anti-allergic effect. In the present study, the antioxidant and cytoprotective effects of Stachys riederi var. japonica ethanol extract (SREE) on ultraviolet A (UVA)-irradiated human dermal fibroblasts (HDFs) were evaluated. At 100 mu g/ml, SREE significantly inhibited production of reactive oxygen species (ROS) in UVA-irradiated HDFs. SREE at 100 mu g/ml additionally markedly interfered with the loss of mitochondrial membrane potential (m) in these cells. In addition, SREE at 100 mu g/ml attenuated UVA-induced DNA fragmentation and caspase-3 activation in HDFs. SREE at 100 mu g/ml additionally increased mRNA and protein expressions of Bcl-2 and decreased those of Bax and cytochrome c in UVA-irradiated HDFs. In summary, to the best of our knowledge, these results demonstrate for the first time that SREE exhibited antioxidant and cytoprotective effects on UVA-irradiated HDFs, which may be mediated through suppression of ROS generation, inhibition of the loss of m and inhibition of apoptosis.