Do Yoon Kim

Background/Objectives: Persicaria senticosa (Meisn.) H.Gross (PS) has anti-photoaging, anti-inflammatory, and antioxidant activities, but the anti-pigmentation potential of the PS flower absolute (PSFAb) remains largely unexplored. This study aimed to examine the chemical composition and anti-melanogenic and melanosome transport-inhibitory effects of PSFAb using B16BL6 murine melanoma cells. Methods: PSFAb was extracted with hexane and analyzed by gas chromatography–mass spectrometry (GC-MS). The biological activities in B16BL6 murine melanoma cells were evaluated using water-soluble tetrazolium salt (WST) assays, 5-bromo-2′-deoxyuridine (BrdU) incorporation, enzyme-linked immunosorbent assays, and immunoblotting methods. Results: GC-MS analysis identified eight constituents in PSFAb. Cell viability was not significantly altered in B16BL6 cells at concentrations ≤ 100 μg/mL, which were used for additional tests. PSFAb inhibited serum-induced cell proliferation and suppressed α-melanocyte-stimulating hormone (α-MSH)-induced melanin synthesis and tyrosinase activity in B16BL6 cells. PSFAb also downregulated the α-MSH-induced expression of key melanogenic regulators, including microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase-related protein-1 (TRP-1), and TRP-2. PSFAb decreased extracellular signal-regulated kinase 1/2 and p38 mitogen-activated protein kinase phosphorylation but enhanced JNK phosphorylation in α-MSH-stimulated B16BL6 cells. Furthermore, PSFAb reduced the α-MSH-induced expression of melanosome transport-related proteins (melanophilin and Rab27a) in B16BL6 cells. Conclusions: Overall, these results suggest that PSFAb has the potential to exert anti-pigmentation effects by suppressing melanogenesis and downregulating melanosome transport-related proteins. Therefore, PSFAb may be a promising candidate for the development of natural agents targeting hyperpigmentation and skin pigmentation regulation.

Background/Objectives: Chamaecyparis pisifera (C. pisifera; family Cupressaceae) is known to have insecticidal and antibacterial activities, but its effects on skin depigmentation-related activities have not been elucidated. Thus, in the present study, we aimed to investigate the anti-hyperpigmentation potential of C. pisifera var. filifera leaf essential oil (CPEO), specially focusing on responses related to melanogenesis and melanin transport, using B16BL6 cells. Methods: CPEO was extracted by steam distillation, and its composition was determined by GC/MS spectrometry. The biological activities of CPEO on B16BL6 melanoma cells were analyzed using the water soluble tetrazolium salt, BrdU incorporation, ELISA, and immunoblotting assays. Results: Twenty-eight components were identified in CPEO. CPEO was noncytotoxic to B16BL6 cells at 1–100 μg/mL and reduced serum-induced proliferation in B16BL6 cells. CPEO significantly inhibited α-MSH-stimulated increases in melanin synthesis and tyrosinase activity in the cells (e.g., at 100 μg/mL CPEO, melanin synthesis: 117.89 ± 0.00% vs. 571.94 ± 0.81% with α-MSH; tyrosinase activity: 73.62 ± 0.00% vs. 322.60 ± 3.10% with α-MSH). CPEO also downregulated the expression levels of melanogenesis-related proteins (MITF, tyrosinase, TRP-1 and -2) and melanosome transport-related proteins (Rab27a, melanophilin, myosin Va) in cells exposed to α-MSH. Moreover, the essential oil increased the phosphorylations of MAPKs (p38, ERK1/2, and JNK) in α-MSH-treated B16BL6 cells. In addition, CPEO reduced the ultraviolet A (UVA) induced increases in α-MSH levels in HaCaT cells. In addition, conditioned medium from HaCaT cells irradiated with UVA (CM-UVA) in the presence of CPEO reduced melanin synthesis and tyrosinase activity in B16BL6 cells (e.g., at CM-UVA with 100 μg/mL CPEO, melanin synthesis: 100.92 ± 0.99% vs. 134.44 ± 0.97% with CM-UVA; tyrosinase activity: 101.02 ± 1.81% vs. 133.77 ± 1.88% with CM-UVA). Conclusions: These findings suggest that CPEO inhibits melanin production (probably through the regulation of MAPKs) and transport-related activities in B16BL6 cells, and that CPEO may serve as a potential natural anti-hyperpigmentation or skin whitening.

Aralia elata (Miq.) Seem. (AES; family Araliaceae) is a medicinal plant and has been reported to have various bioactivities, including anticancer and hepatotoxicity protective activities. However, no studies have investigated the biological activities of AES or its extracts on skin. To address this, we aimed to explore the effect of AES-flower-derived absolute-type essential oil (AESFEO) on skin-related biological activities, especially skin wound healing and whitening-related responses in skin cells (human-derived keratinocytes [HaCaT cells] and melanocytes [B16BL6 cells]) and to identify the components of AESFEO. Cell biological activities were analyzed using WST and BrdU incorporation assays, ELISA, or by immunoblotting. In HaCaT cells, AESFEO promoted proliferation, type IV collagen production, and enhanced the phosphorylations of Erk1/2, p38 MAPK, JNK, and Akt. In B16BL6 cells, AESFEO reduced serum-induced proliferation, α-MSH-stimulated increases in melanin synthesis and tyrosinase activity, and α-MSH-induced increases in MITF, tyrosinase, TRP-1, and TRP-2 expressions. In addition, AESFEO inhibited the phosphorylation of Erk1/2, p38 MAPK, and JNK in α-MSH-stimulated B16BL6 cells. Eighteen compounds were identified in AESFEO by GC/MS. These results suggest that AESFEO has beneficial effects on keratinocyte activities related to skin wound healing and melanocyte activities related to inhibition of skin pigmentation. AESFEO may serve as a useful natural substance for developing agents that facilitate skin wound healing and inhibit melanogenesis.

Siegesbeckia glabrescens Makino (SGM) has been traditionally used to treat many disorders, including rheumatoid arthritis, hypertension, and acute hepatitis. However, the biological activities of SGM in skin remain unclear. The present study explored the effects of SGM flower absolute (SGMFAb) on skin-whitening-linked biological activities in B16BL6 cells. SGMFAb was extracted using hexane, and its composition was analyzed through gas chromatography/mass spectrometry analysis. The biological effects of SGMFAb on B16BL6 melanoma cells were detected via WST and BrdU incorporation assays, ELISA, and immunoblotting. SGMFAb contained 14 compounds. In addition, SGMFAb was noncytotoxic, attenuated the serum-induced proliferation of, and inhibited melanin synthesis and tyrosinase activity in α-MSH-exposed B16BL6 cells. SGMFAb also reduced the expressions of MITF (microphthalmia-associated transcription factor), tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2 in α-MSH-exposed B16BL6 cells. Moreover, SGMFAb downregulated the activation of p38 MAPK, ERK1/2, and JNK in α-MSH-stimulated B16BL6 cells. In addition, SGMFAb reduced the expressions of three melanosome-transport-participating proteins (myosin Va, melanophilin, and Rab27a) in α-MSH-stimulated B16BL6 cells. These results indicate that SGMFAb positively influences skin whitening activities by inhibiting melanogenesis and melanosome-transport-related events in B16BL6 cells, and suggest that SGMFAb is a promising material for developing functional skin whitening agents.

Caragana sinica (CS; family Legume) was used as a medicinal material to treat neuralgia and arthritis in folk remedies and has been shown to have antioxidant, neuroprotective, and anti-apoptotic effects. However, CS is unknown for its biological activities related to skin. The present study explored the effects of CS flower absolute (CSFAb) on skin repair responses, viz., wound healing and anti-wrinkle-related responses using keratinocytes. CSFAb was extracted using hexane, and its composition was analyzed by GC/MS. The effects of CSFAb on human keratinocytes (HaCaT cells) were evaluated using Boyden chamber, sprouting, water-soluble tetrazolium salt, 5-bromo-2′-deoxyuridine incorporation, ELISA, zymography, and immunoblotting assays. GC/MS detected 46 components in CSFAb. In addition, in HaCaT cells, CSFAb increased the proliferation, migration, and sprout outgrowth and the phosphorylation of ERK1/2, JNK, p38 MAPK, and AKT, and also increased collagen type I and IV synthesis, reduced TNF-α-increased MMP-2 and MMP-9 activities, and upregulated hyaluronic acid (HA) and HA synthase-2 levels. These effects of CSFAb on wound healing and anti-wrinkle-related responses in keratinocytes suggest its potential use for skin repair and care preparations.

Impatiens textori Miq. (ITM; family Balsaminaceae) is a traditional medicinal plant with many biological activities, which include anti-allergic, anti-inflammatory, and anti-pruritic properties. However, it remains to be determined whether ITM affects biological activities in the skin. Thus, we investigated the effects of ITM flower absolute (ITMFAb) extract on the biological activities of skin, especially those related to skin wound repair and whitening. ITMFAb was extracted with hexane, and its composition was determined through GC/MS. The biological activities of ITMFAb on HaCaT keratinocytes and B16BL6 melanoma cells were analyzed using a water-soluble tetrazolium salt, 5-bromo-2′-deoxyuridine incorporation, a Boyden chamber, an ELISA, a sprouting assay, and by immunoblotting. These analyses were performed in a range of ITMFAb concentrations that did not inhibit the viability of the cells (HaCaT, ≤400 µg/mL; B16BL6, ≤200 µg/m). Forty components were identified in ITMFAb. ITMFAb stimulated proliferation, migration, sprout outgrowth, and type I and IV collagen synthesis and upregulated the activations of ERK1/2, JNK, p38 MAPK, and AKT in HaCaT cells. In addition, ITMFAb attenuated the serum-induced proliferation of B16BL6 cells. ITMFAb inhibited melanin synthesis, tyrosinase activity, and expressions of MITF and tyrosinase in α-MSH-exposed B16BL6 cells. These findings indicate that ITMFAb has beneficial effects on wound repairing and whitening-linked responses in the skin and suggest the potential use of ITMFAb as a natural material for the development of skin wound repair and whitening agents.

Atopic dermatitis (AD) is a chronic inflammatory dermal disease with symptoms that include inflammation, itching, and dry skin. 1-Iodohexadecane is known as a component of Chrysanthemum boreale essential oil that has an inhibitory effect on AD-like lesions. However, its effects on AD-related pathological events have not been investigated. Here, we explored the effects of 1-iodohexadecane on AD lesion-related in vitro and in vivo responses and the mechanism involved using human keratinocytes (HaCaT cells), mast cells (RBL-2H3 cells), and a 2,4-dinitrochlorobenzene (DNCB)-induced mouse model (male BALB/c) of AD. Protein analyses were performed by immunoblotting or immunohistochemistry. In RBL-2H3 cells, 1-iodohexadecane inhibited immunoglobulin E-induced releases of histamine and β-hexosaminidase and the expression of VAMP8 protein (vesicle-associated membrane proteins 8; a soluble N-ethylmaleimide-sensitive factor attachment protein receptor [SNARE] protein). In HaCaT cells, 1-iodohexadecane enhanced filaggrin and loricrin expressions; in DNCB-treated mice, it improved AD-like skin lesions, reduced epidermal thickness, mast cell infiltration, and increased filaggrin and loricrin expressions (skin barrier proteins). In addition, 1-iodohexadecane reduced the β-hexosaminidase level in the serum of DNCB-applied mice. These results suggest that 1-iodohexadecane may ameliorate AD lesion severity by disrupting SNARE protein-linked degranulation and/or by enhancing the expressions of skin barrier-related proteins, and that 1-iodohexadecane has therapeutic potential for the treatment of AD.

Salix koreensis Anderss (SKA) has been used traditionally to treat inflammation, pain, and edema. SKA has anti-inflammatory and antioxidant effects, but no study has examined its effects on skin wound healing. Here, we aimed to investigate the effects of the absolute extracted from SKA flower (SKAFAb) on skin wound healing-associated responses in keratinocytes. SKAFAb was produced using a solvent extraction method and its chemical composition was analyzed by gas chromatography/mass spectrometry. The effects of SKAFAb on HaCaT cells (a human epidermal keratinocyte cell line) were investigated using a Boyden chamber and 5-bromo-2′-deoxyuridine incorporation, sprout outgrowth, immunoblotting, enzyme-linked immunosorbent, and water-soluble tetrazolium salt assays. Sixteen constituents were identified in SKAFAb. SKAFAb promoted HaCaT cell proliferation, migration, and type I and IV collagen productions. SKAFAb increased sprout outgrowth and increased the phosphorylations of serine/threonine-specific protein kinase (Akt), c-Jun NH2-terminal kinase, extracellular signal-regulated kinase1/2, and p38 mitogen-activated protein kinase (MAPK) in HaCaT cells. These results indicate that SKAFAb promotes keratinocyte proliferation and migration, probably by activating Akt and MAPK signaling pathways, and induces collagen synthesis in keratinocytes. SKAFAb may be a promising material for promoting skin wound healing.

Angelica polymorpha Maxim. (APM) is used in traditional medicine to treat chronic gastritis, rheumatic pain, and duodenal bulbar ulcers. However, it is not known whether APM has epidermis-associated biological activities. Here, we investigated the effects of APM flower absolute (APMFAb) on responses associated with skin wound healing and whitening using epidermal cells. APMFAb was obtained by solvent extraction and its composition was analyzed by GC/MS. Water-soluble tetrazolium salt, 5-bromo-2′-deoxyuridine incorporation, Boyden chamber, sprouting, and enzyme-linked immunosorbent assays and immunoblotting were used to examine the effects of APMFAb on HaCaT keratinocytes and B16BL6 melanoma cells. APMFAb contained five compounds and induced keratinocyte migration, proliferation, and type IV collagen synthesis. APMFAb also induced the phosphorylations of ERK1/2, JNK, p38 mitogen-activated protein kinase, and AKT in keratinocytes. In addition, APMFAb decreased serum-induced B16BL6 cell proliferation and inhibited tyrosinase expression, melanin contents, and microphthalmia-associated transcription factor expression in α-melanocyte-stimulating hormone-stimulated B16BL6 cells. These findings demonstrate that APMFAb has beneficial effects on skin wound healing by promoting the proliferation, migration, and collagen synthesis of keratinocytes and on skin whitening by inhibiting melanin synthesis in melanoma cells. Therefore, we suggest that APMFAb has potential use as a wound healing and skin whitening agent.