Laminaria japonica Suppresses the Atopic Dermatitis-Like Responses in NC/Nga Mice and Inflamed HaCaT Keratinocytes via the Downregulation of STAT1

Abstract

Atopic dermatitis (AD) is a skin allergy accompanied by acute and chronic dermal inflammation. In traditional oriental medicine, Laminaria japonica has been used to treat various diseases, including inflammatory diseases. Therefore, to determine the therapeutic potential of L. japonica against AD, we investigated the inhibitory effects of L. japonica water extract (LJWE) on the inflammatory mediators and AD-like skin lesions. We determined the cell viability of LJWE-treated HaCaT cells using the cell counting kit-8 assay and the levels of inflammatory cytokines using cytometric bead array kits. Additionally, we analyzed the modulatory effects of LJWE on the signaling pathways in tumor necrosis factor-α/interferon-γ-stimulated HaCaT cells via Western blotting. Furthermore, we determined the in vivo effect of LJWE on NC/Nga mice and found that LJWE remarkably improved the skin moisture, reduced dermatitis severity, and inhibited the overproduction of inflammatory mediators in 2,4-dinitrochlorobenzene-sensitized NC/Nga mice. We also observed that LJWE inhibits the expression of inflammatory chemokines in human keratinocytes by downregulating the p38 mitogen-activated protein kinase signaling pathway and activating the signal transducer and activator of transcription 1. In conclusion, LJWE has the therapeutic potential against AD by healing AD-like skin lesions, and suppressing inflammatory mediators and major signaling molecules.

Brown Seaweed Food Supplementation: Effects on Allergy and Inflammation and Its Consequences

“…This reduces nasal rubbing [ 15 ] or clinical signs of atopic dermatitis, as well as inflammatory cytokine levels and leukocyte skin infiltrates [ 16 ] in these allergy models. Similarly, application of extracts from Costaria costata [ 17 ] and Laminaria japonica [ 18 ] reduce severity of allergic dermatitis and stimulate healing, possibly by decreasing inflammatory pathways in keratinocytes.…”

“…+ DNP i.n. challenge allergy ↓ nasal rubbing ↓ mast cell degranulation Proposed mechanism: Chlorophyll-C2 →↓ PI-3K + ↓ Btk, ↓ Syk active upon FcεR trigger →↓ Ca-mobilization [ 15 ] EtOH extract 10, 50, 100 mg/kg, 1×/day, 3 weeks Sargassum horneri female NC/Nga mouse; house dust mite/dayNCB skin sensibilization DNCB skin challenge (2×/week) allergy ↓ atopic dermatitis symptoms ↓ epidermal hyperplasia, hyperkeratosis, skin dryness ↓ mast cell + eosinophil skin infiltrates ↓ IL-25, IL-33 → ↓ Rantes (CCL5), Eotaxin (CCL11), TARC (CCL17) in skin ↓ IL-4, -5, -13, ↓ IL-6, -10, IFN-γ in serum ↓ spleen size increase ↓ IgG1, IgG2a increase [ 16 ] EtOH extract 100–300 mg/kg/day in diet, 5 weeks Costaria costata male NC/Nga mouse; DNCB-induced atopic dermatitis skin allergy allergy ↓ inflammatory cell and mast cell infiltration, epidermal thickness, erythema, hemorrhage, dead skin cell layers, skin dehydration ↓ Eotaxin and TARC (CCL17)↓ serum IgE and histamine normalization of spleen lymphocyte proliferation and cytokine production [ 17 ] water extract 100–300 mg/kg/day, 4 weeks Laminaria japonica female NC/Nga mouse; DNCB-sensitized and challenged dorsal skin allergy ↓ dermatitis severity; ↓ inflammatory mediators ↑ skin moisture in vitro: ↓ p38 MAPK,↑ ERK, ↓ STAT1 in HaCaT human keratinocyte cell line [ 18 ] dried powder 1–5–10%, 6 weeks Eisenia (=Ecklonia) arborea ...…”

Two Laminaria japonica Fermentation Broths Alleviate Oxidative Stress and Inflammatory Response Caused by UVB Damage: Photoprotective and Reparative Effects

“…Laminaria japonica is rich in polysaccharides and polyphenols, which are the primary substances with antioxidant and anti-inflammatory effects [ 19 , 23 ].…”

“…Studies have confirmed that Laminaria japonica specifically inhibits the nuclear translocation of the STAT1 gene through the MAPK pathway, reduces skin inflammation and the expression level of cellular inflammatory chemokines, and inhibits the loss of skin moisture in mice caused by dinitrochlorobenzene (NC/Nga) sensitization [ 18 ]. Fucoidan extracted from Laminaria japonica has been confirmed to reduce the content of tumor necrosis factor α (TNF-α) in THP-1 cells caused by lipopolysaccharide (LPS), and it can be reduced by 50% at 50 μg/mL [ 19 ]. Research on the anti-inflammatory activity of Laminaria japonica is emerging, but it remains blank in terms of UVB radiation.…”

Pinus koraiensis needle or cone extracts alleviate atopic dermatitis symptoms by regulating immunity and suppressing inflammation in HaCaT cells and Nc/Nga mice

“…In the present study, Nc/Nga mice aged 7–8 weeks were maintained on a high‐fat diet exacerbates the development of AD‐like symptoms (Jena et al, 2019). However, they were too young to show severe AD symptoms, which were developed after DNCB treatment of the dorsal skin (Hwang et al, 2020; Jeong et al, 2020). Jena et al (2019) reported that long‐term intake of high‐fat diets, corresponding to Western‐style diets, results in dermatitis by activating Th2 and Th17 cells in C57BL/6 mice.…”