Inhibition of melanogenesis by Aster yomena callus pellet extract in melanoma cells and patients with skin pigmentation.

Plant tissue culture holds immense potential for the production of secondary metabolites with various physiological functions. We recently established a plant tissue culture system capable of producing secondary metabolites from Aster yomena. This study aimed to uncover the mechanisms underlying the potential therapeutic effects of Aster yomena callus pellet extract (AYC-P-E) on photoaging-induced skin pigmentation. Excessive melanogenesis was induced in B16F10 melanoma cells using α-melanocyte stimulating hormone (α-MSH). The effects of AYC-P-E treatment on melanin biosynthesis inducers and melanin synthesis inhibition were assessed. Based on the results, a clinical study was conducted in subjects with skin pigmentation. AYC-P-E inhibited melanogenesis in α-MSH-treated B16F10 cells, accompanied by decreased mRNA and protein expression of melanin biosynthesis inducers, including cyclic AMP response element-binding protein (CREB), tyrosinase, microphthalmia-associated transcription factor (MITF), tyrosinase related protein-1 (TRP-1), and TRP-2. This anti-melanogenic effect was mediated by mitogen-activated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) and protein kinase B (AKT) phosphorylation. Treatment of subjects with skin pigmentation with AYC-P-E-containing cream formulations resulted in 3.33%, 7.06%, and 8.68% improvement in the melanin levels at 2, 4, and 8 weeks, respectively. Our findings suggest that AYC-P-E inhibits excessive melanogenesis by activating MEK/ERK and AKT signaling, potentiating its cosmetic applications in hyperpigmentation treatment.

The Metabolite Profile in Culture Supernatant of Aster yomena Callus and Its Anti-Photoaging Effect in Skin Cells Exposed to UVB.

Aster yomena (A. yomena) extract has anti-inflammatory, antioxidant, anti-asthma, and anti-atopic effects. However, the commercial use of A. yomena extract requires a long processing time with specific processing steps (including heat treatment and ethanol precipitation), and there are various environmental problems. We aimed to build a system to produce A. yomena extract by culturing the callus in a bioreactor that can allow rapid process scale-up to test the effect of extract (AYC-CS-E) isolated from culture supernatant of A. yomena callus on photoaging of human keratinocytes (HaCaT) caused by ultraviolet B (UVB) exposure. Through screening analysis based on ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS), 17 major metabolites were tentatively identified from AYC-CS-E for the first time. The suppression of cell proliferation caused by UVB was effectively alleviated in UVB-irradiated HaCaT cells treated with AYC-CS-E. Treatment with AYC-CS-E strongly induced the formation of type I procollagen and the inhibition of elastase in UVB-irradiated HaCaT cells and significantly reduced the expression of matrix metalloproteinase (MMP)-1. In addition, treatment of UVB-irradiated HaCaT cells with AYC-CS-E effectively improved various factors associated with an inflammatory reaction, skin damage recovery, skin moisture retention, and hyper-keratinization caused by photoaging, such as reactive oxygen species (ROS), pro-inflammatory cytokines, transforming growth factor beta (TGF-ß), MMP-3, MMP-9, filaggrin, hyaluronic acid synthase 2 (HAS-2), keratin 1 (KRT-1), nuclear factor-kappa B (NF-κB), and nuclear factor erythroid 2-related factor 2 (Nrf2) at the gene and protein levels. These results suggest that AYC-CS-E can be used as a cosmetic ingredient for various skin diseases caused by photoaging, and the current callus culture system can be used commercially to supply cosmetic ingredients.