Byul-Nim Ahn

1-(3′,5′-dihydroxyphenoxy)-7-(2″,4″,6-trihydroxyphenoxy)-2,4,9-trihydroxydibenzo-1,4-dioxin Inhibits Adipocyte Differentiation of 3T3-L1 Fibroblasts

In this study, we isolated the phloroglucinol derivative, 1-(3′,5′-dihydroxyphenoxy)-7-(2″,4″,6-trihydroxyphenoxy)-2,4,9-trihydroxydibenzo-1,4-dioxin (1), from Ecklonia cava and evaluated its potential inhibition on adipocyte differentiation in 3T3-L1 cells. Lipid accumulation along with the expression of several genes associated with adipogenesis and lipolysis was examined at the end of differentiation. Lipid accumulation level was examined by measuring triglyceride content and Oil-Red O staining. The expression levels of several genes and proteins were examined using reverse-transcription polymerase chain reaction (RT-PCR), real-time RT-PCR, and Western blot analysis. Compound 1 significantly reduced lipid accumulation and downregulated peroxisome proliferator-activated receptor-γ, sterol regulatory element-binding protein 1c, and CCAAT/enhancer-binding proteins α in a dose-dependent manner. Moreover, the presence of compound 1 induced downregulation of adipogenic target genes such as fatty acid binding protein 4, fatty acid transport protein 1, fatty acid synthase, acyl-CoA synthetase 1, lipoprotein lipase, and leptin. According to the lipolytic response, compound 1 downregulated perilipin and hormone-sensitive lipase while upregulating tumor necrosis factor alpha. Therefore, these results suggest that compound 1 might decrease lipid accumulation during adipocyte differentiation by modulating adipogenesis and lipogenesis. Furthermore, compound 1 could be developed as a functional agent effective in improving obesity.

The chromene sargachromanol E inhibits ultraviolet A-induced ageing of skin in human dermal fibroblasts.

Background  Skin ageing is influenced by environmental factors such as ultraviolet (UV) radiation. The effects of UV radiation on skin functions should be investigated using human in vitro models to understand the mechanisms of skin ageing. Additionally, marine algae provide a valuable source for identifying and extracting biologically active substances.

Anti-inflammatory action of sulfated glucosamine on cytokine regulation in LPS-activated PMA-differentiated THP-1 macrophages

ObjectiveThe aim of this study was to evaluate the effect of sulfated glucosamine (SGlc) on the regulation of inflammatory cytokines and profiles involved in immunological activities. Changes in the inflammatory profiles of lipopolysaccharide (LPS)-activated phorbol 12-myristate 13-acetate (PMA)-differentiated THP-1 macrophage models were investigated following SGlc treatment.MethodsHuman THP-1 macrophages were used to evaluate anti-inflammatory profiles. The cytokine secretion levels were measured by enzyme-linked immunosorbent assay (ELISA). Effects of SGlc on the regulation of mRNA and protein levels were determined using RT-PCR and Western blot analysis. The effect of SGlc on the activation of mitogen-activated protein kinases (MAPKs) and NF-κB protein was also determined by Western blot analysis.ResultsTreatment of THP-1 cells with SGlc inhibited the production of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6. In addition, SGlc suppressed the mRNA and protein expression levels of inflammatory mediators such as inducible nitric oxide synthase, cyclooxygenase-2, TNF-α, IL-1β, IL-6, 5-lipoxygenase and cytoplasmic phospholipase A2 in LPS-activated THP-1 macrophages. Furthermore, we confirmed that the LPS-activated transcriptions of MAPKs and NF-κB were inhibited by SGlc treatment in PMA-differentiated THP-1 macrophages.ConclusionThese results suggest that SGlc can be considered as a potential anti-inflammatory supplement.

Ecklonia cava promotes hair growth

Previous studies have reported the protective effects on skin elasticity of the edible marine seaweed Ecklonia cava, which acts through regulation of both antioxidative and anti‐inflammatory responses.

Effect of Salicornia herbacea on Osteoblastogenesis and Adipogenesis in Vitro

Bone-related complications are among the highest concerning metabolic diseases in the modern world. Bone fragility and susceptibility to fracture increase with age and diseases like osteoporosis. Elevated adipogenesis in bone results in osteoporosis and loss of bone mass when coupled with lack of osteoblastogenesis. In this study the potential effect of Salicornia herbacea extract against osteoporotic conditions was evaluated. Adipogenesis inhibitory effect of S. herbacea has been evidenced by decreased lipid accumulation of differentiating cells and expression levels of crucial adipogenesis markers in 3T3-L1 pre-adipocytes. S. herbacea treatment reduced the lipid accumulation by 25% of the control. In addition, mRNA expression of peroxisome proliferator-activated receptor (PPAR)γ, CCAAT/enhancer-binding protein (C/EBP)α and sterol regulatory element binding protein (SREBP)1c were inhibited by the presence of S. herbacea. Bone formation enhancement effect of S. herbacea was also confirmed in MC3T3-E1 pre-osteoblasts. The presence of S. herbacea significantly elevated the alkaline phosphatase (ALP) activity by 120% at a concentration of 100 μg/mL in differentiating osteoblasts. S. herbacea also significantly increased the expression of osteoblastogenesis indicators, ALP, bone morphogenetic protein (BMP)-2, osteocalcin and collagen type I (collagen-I). In conclusion, S. herbacea possess potential to be utilized as a source of anti-osteoporotic agent that can inhibit adipogenesis while promoting osteoblastogenesis.

Dioxinodehydroeckol protects human keratinocyte cells from UVB-induced apoptosis modulated by related genes Bax/Bcl-2 and caspase pathway

Although ultraviolet B (UVB) has a low level of skin penetration, it readily results in epidermal sunburn of keratinocytes that are destined to apoptosis after sun expose, and leads to DNA damage. Dioxinodehydroeckol (DHE), a phlorotannin from Ecklonia cava has been explored for its preventive activity against UVB-induced apoptosis in human keratinocyte (HaCaT) cells; however, the protective effects of treatment with low doses of DHE on UVB-damaged cells post-UVB exposure and their underlying mechanisms still remain unclear. The HaCaT cells were exposed to 20 mJcm(-2) of UVB irradiation which is the minimal erythema dose (MED) for individuals to be able to tan, and the expression levels of Bax/Bcl-2 and caspase-3,-8, -9 which are associated genes with apoptosis were investigated when we either treated cells with DHE doses after UVB irradiation or exposed them to UVB only. Our results suggest insight into proposed mechanistic pathway of protective activity of DHE on the HaCaT cells from UVB-induced apoptosis, indicating the benefit of DHE as a repair agent for skin damage against UVB.

Antiphotoaging effect of chitooligosaccharides on human dermal fibroblasts

In the present study, the effect of 3–5 kDa chitooligosaccharide (COS) on homeostasis between the expression of collagen‐degrading matrix metalloproteinases (MMPs) and collagen synthesis was investigated using ultraviolet (UV)‐A irradiated dermal fibroblasts.

Photodamage attenuation effect by a tetraprenyltoluquinol chromane meroterpenoid isolated from Sargassum muticum.

A tetraprenyltoluquinol meroterpenoid with a chromane moiety, obtained as an epimeric mixture at C3, was isolated for the first time from the dichloromethane fraction of a methanolic extract from the brown alga Sargassum muticum. The structure has been established by means of spectral methods including NMR spectroscopy and MS and comparison with reported data. The compound showed photodamage attenuation on irradiated cells with UVA light, presented protection against intracellular ROS generation in a degree comparable to retinoic acid (9.1-20.6%) and did not display toxicity against human dermal fibroblast cells.

Potential effect of phloroglucinol derivatives from Ecklonia cava on matrix metalloproteinase expression and the inflammatory profile in lipopolysaccharide-stimulated human THP-1 macrophages

The effects of the phloroglucinol derivatives dioxinodehydroeckol (1) and 1-(3′,5′-dihydroxyphenoxy)-7-(2″,4″,6-trihydroxyphenoxy)-2,4,9-trihydroxydibenzo-1,4-dioxin) (2) from Ecklonia cava on matrix metalloproteinase (MMP) expression and the inflammatory profile were investigated in lipopolysaccharide (LPS)-stimulated human THP-1 macrophage cell models. Treatment with phloroglucinol derivatives inhibited MMP expression and the production of pro-inflammatory cytokines such as IL-1β, IL-6 and TNF-α. In addition, the presence of compounds 1 and 2 suppressed the regulation of inflammatory mediators such as IL-1β, IL-6, TNF-α, iNOS and COX-2 in LPS-stimulated THP-1 macrophages. Furthermore, we confirmed that the LPS-induced transcription activity of MAPK in PMA-differentiated THP-1 macrophages was inhibited by phloroglucinol derivatives. As a result of this study, phloroglucinol derivatives can be considered potential anti-inflammatory agents.

Dioxinodehydroeckol Enhances the Differentiation of Osteoblasts by Regulating the Expression of Phospho-Smad1/5/8.

Lack of bone formation-related health problems are a major problem for the aging population in the modern world. As a part of the ongoing trend of developing natural substances that attenuate osteoporotic bone loss conditions, dioxinodehydroeckol (DHE) from edible brown alga Ecklonia cava was tested for its effects on osteoblastogenic differentiation in MC3T3-E1 pre-osteoblasts. DHE was observed to successfully enhance osteoblast differentiation, as indicated by elevated cell proliferation, alkaline phosphatase activity, intracellular cell mineralization, along with raised levels of osteoblastogenesis indicators at the concentration of 20 μM. Results suggested a possible intervening of DHE on the bone morphogenetic protein (BMP) signaling pathway, according to elevated protein levels of BMP-2, collagen-I, and Smads. In addition, the presence of DHE was also able to raise the phosphorylated extracellular signal–regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) levels which are also activated by the BMP signaling pathway. In conclusion, DHE is suggested to be a potential bioactive compound against bone loss that could enhance osteoblastogenesis with a suggested BMP pathway interaction.