In this study, we investigated the antioxidant activities on HaCaT and the whitening effects on B16F1 melanoma cells of Dendropanax morbifera leaf extract. In an antioxidative activity assay using HaCaT cells, the ethyl acetate (50 μg/ml) and aglycone fractions (25 μg/ml) of the D. morbifera leaf extract didn't exhibit any characteristics of cytotoxicity. When HaCaT cells were exposed to a single large dose (800 mJ/cm 2 ) of UVB, the extracts protected the cells against UVB radiation. When HaCaT cells were treated with 10 mM H 2 O 2 and 4 μM rose bengal, the ethyl acetate (6.25~50 μg/ml) and aglycone (6.25~25 μg/ml) fractions protected the cells against oxidative damage in a concentration dependent manner. When the whitening effects of D. morbifera leaf extract were tested in melanoma B16/F1 cells treated with the a-melanocyte stimulating hormone (α-MSH), the extracts inhibited α-MSH-stimulated intra/extracellular melanogenesis in a concentration dependent manner. The inhibitory effects of the ethyl acetate and aglycone fractions of D. morbifera leaf extract were 21% and 44% at 25 μg/ml, respectively. Both are more effective than arbutin (15% at 25 μg/ml) which is known as a whitening agent. These results indicate that fractions of the D. morbifera leaf can function as cell protectants and natural antioxidants in biological systems, particularly skins exposed to UV radiation by quenching and/or scavenging 1 O 2 and other ROS, and protecting cells against ROS. In addition, fractions of the D. morbifera leaf can be applied to new whitening cosmetics because of their inhibitory effects on α-MSH stimulated melanogenesis in B16F1 melanoma cells.

Background Chronic myelomonocytic leukemia (CMML) is characterized by persistent monocytosis and dysplastic features of blood cells. No specific genetic abnormalities are present in CMML, and reactive monocytosis should be excluded. An increase in classical monocytes (MO1) has been suggested as a screening tool for CMML. Methods We evaluated monocyte subsets in the peripheral blood of patients with CMML (n = 16), patients with reactive monocytosis (n = 19), and normal controls (n = 15) with flow cytometry using antibodies against CD14, CD16, CD56, CD24, CD45, and CD2. The cutoff of MO1 ≥94% was validated, and the optimal cutoff was analyzed with receiver operating curve analysis. Results The sensitivity of monocyte subset testing for screening for CMML was 0.938 (0.717‐0.997), and the specificity was 0.882 (0.734 ‐ 0.953) using the cutoff of MO1 ≥94%. Serial samples from patients who responded to hypomethylating therapy showed an MO1 < 94%. However, few patients with reactive monocytosis, including patients with nonhematologic malignancies and acute myeloid leukemia, showed an increase in the MO1 ≥ 94%. Monocyte subset results were correlated with the response to hypomethylating therapy in follow‐up samples. Conclusion Monocyte subset analysis is useful in screening for and monitoring CMML. Harmonization of the protocols for monocyte subset analysis is required.