Caesalpinia sappan L., belonging to the family Leguminosae, is a medicinal plant
that is distributed in Southeast Asia. The dried heartwood of this plant is used as
a traditional ingredient of food, red dyes, and folk medicines in the treatment of
diarrhea, dysentery, tuberculosis, skin infections, and inflammation. Brazilin is
the major active compound, which has exhibited various pharmacological effects, including
anti-platelet activity, anti-hepatotoxicity, induction of immunological tolerance,
and anti-inflammatory and antioxidant activities. The present study aimed to evaluate
the antioxidant activity and expression of antioxidant enzymes of C. sappan L. extract
and its major compound, brazilin, in human epidermal keratinocytes exposed to UVA
irradiation. Our results indicated that C. sappan L. extract reduced UVA-induced
H 2 O 2 production via GPX7 activation. Moreover, brazilin exhibited antioxidant
effects that were similar to those of C. sappan L. via glutathione peroxidase
7 (GPX7), suggesting that C. sappan L. extract and its natural compound represent
potential treatments for oxidative stress-induced photoaging of skin.