Neonauclea reticulata(Havil.) Merr Stimulates Skin Regeneration after UVB Exposure via ROS Scavenging and Modulation of the MAPK/MMPs/Collagen Pathway

Abstract

In this study, we investigated whether the protective effects ofNeonauclea reticulatawater extract against ultraviolet B (UVB) irradiation in human skin fibroblast cell cultures (Hs68) are governed by its ability to protect against oxidative stress and expression of matrix metalloproteinases (MMPs). We found thatNeonauclea reticulataextract exhibited DPPH scavenging activity and inhibited AAPH-induced haemolysis of erythrocytes in a dose- and time-dependent manner. We also found that pretreatment of fibroblasts withNeonauclea reticulatawater extract resulted in markedly lower levels of MMP-1, -3, and -9 expressions. Furthermore, our results indicate thatNeonauclea reticulataextract inhibits the expression of MMPs by inhibiting ERK, JNK, and p38 phosphorylation. Our results also demonstrate that treatment withNeonauclea reticulataextract protects against UVB-induced depletion of collagen. In addition,Neonauclea reticulataextract did not have a cytotoxic effect. These findings indicate that the antioxidant activity ofNeonauclea reticulataextract resulted in inhibition of MMP-1, -3, and -9 expressions and in increased levels of collagen activity. Our results suggest thatNeonauclea reticulataextract can protect against photoaging.