Publications by authors named "Bong-Hwan Park"

Ginsenoside F1, the metabolite of Rg1, is one of the most important constituents of . Although the effects of ginsenosides on amyloid beta (Aβ) aggregation in the brain are known, the role of ginsenoside F1 remains unclear. Here, we investigated the protective effect of ginsenoside F1 against Aβ aggregation in vivo and in vitro.

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A-disintegrin and metalloproteinase 10 (ADAM10) is involved in the generation of amyloid-β (Aβ) during amyloid precursor protein (APP) processing, and has a protective effect against Aβ neurotoxicity. We explored how metallothionein-III (MT-III) is regulated in the non-amyloidogenic pathway to generate soluble APPα (sAPPα). MT-ІІІ increased sAPPα levels and reduced Aβ peptide levels, but did not affect ADAM10 expression.

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Purpose: The consequences of precipitously rising allergic skin inflammation rates worldwide have accelerated the risk of atopic dermatitis (AD). Natural product-based agents with good efficacy and low risk of side effects offer promising prevention and treatment strategies for inflammation-related diseases. We have already reported that Platycodon grandiflorum root-derived saponins (Changkil saponins, CKS) have many pharmacological effects, including anti-inflammatory and anti-allergic effects, but its influence on AD remains unclear.

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Piperine is a bioactive component of black pepper, Piper nigrum Linn, commonly used for daily consumption and in traditional medicine. Here, the molecular mechanisms by which piperine exerts antitumor effects in HER2-overexpressing breast cancer cells was investigated. The results showed that piperine strongly inhibited proliferation and induced apoptosis through caspase-3 activation and PARP cleavage.

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Ginseng contains many bioactive constituents, including various ginsenosides that are believed to have anti-allergic, anti-oxidant, and immunostimulatory activities; however, its effects on atopic dermatitis (AD) remain unclear. In the current study, we hypothesized that cultivated ginseng (CG) would inhibit 2,4-dinitrochlorobenzene (DNCB)-induced AD-like skin lesions in NC/Nga mice by regulating the T helper (Th)1/Th2 balance. Also, CG inhibits TNF-α/IFN-γ-induced thymus- and activation-regulated chemokine (TARC) expression through nuclear factor-kappa B (NF-κB)-dependent signaling in HaCaT cells.

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Phillyrin, an active constituent found in many medicinal plants and certain functional foods, has anti-obesity activity in vivo. The aim of our study was to provide new data on the molecular mechanism(s) underlying the role of phillyrin in the prevention of high glucose-induced lipid accumulation in human HepG2 hepatocytes. We found that phillyrin suppressed high glucose-induced lipid accumulation in HepG2 cells.

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Atopic dermatitis (AD) is a chronic, relapsing, and inflammatory skin disease associated with eczematous symptoms and IgE hyperproduction. Psidium guajava is an important food crop and medicinal plant with anti-oxidant, anti-inflammatory, and anti-allergic activities, supporting its traditional uses. Our previous studies have shown that P.

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Piperine is a major component of black (Piper nigrum Linn) and long (Piper longum Linn) peppers, and is widely used as a traditional food and medicine. It also exhibits a variety of biological activities, which include antioxidant, anti-tumor and anti-pyretic properties. In the present study, we investigated the inhibitory effects of piperine on phorbol 12-myristate 13-acetate (PMA)-induced cyclooxygenase-2 (COX-2) gene expression and analyzed the molecular mechanism of its activity in murine RAW 264.

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Baicalin, a glycoside present in Scutellaria baicalensis Georgi, is metabolized to its aglycone, baicalein, in intestine. In the present study, possible role of metabolism of baicalin by intestinal bacteria to baicalein in baicalin-induced toxicity was investigated in HepG2 cell cultures. As an intestinal bacterial metabolic system for baicalin, human fecal preparation containing intestinal microflora (fecalase) was employed.

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Platycodi Radix has been used to treat chronic diseases, such as bronchitis, asthma, and hyperlipidemia. In this study, we examined the effect of an aqueous extract, Changkil (CK), from the root of Platycodi Radix on 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD)-like skin lesions. Administration of CK onto DNCB-induced AD-like skin lesions in NC/Nga mice ameliorated lesion intensity scores, levels of IgE, thymus and activation-regulated chemokine (TARC), TNF-α, and IL-4 in serum and ears.

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During the process of liver fibrosis, hepatic stellate cells (HSCs) play a critical role in the increased formation and reduced degradation of extracellular matrix in the liver. We investigated the anti-proliferative effects of an anthocyanin fraction (AF), isolated from the purple-fleshed sweet potato, on platelet-derived growth factor (PDGF)-BB-dependent signaling pathways in HSC-T6 cells. HSC proliferation plays a pivotal role in liver fibrogenesis.

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Mucin overproduction is a hallmark of chronic airway diseases such as chronic obstructive pulmonary disease. In this study, we investigated the inhibition of acrolein-induced expression of mucin 5, subtypes A and C (MUC5AC) by Changkil saponin (CKS) in A549 cells. Acrolein, a known toxin in tobacco smoke and an endogenous mediator of oxidative stress, increases the expression of airway MUC5AC, a major component of airway mucus.

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Background: N-Acetylglucosamine (GlcNAc) and its derivates have been utilized in dietary supplements and for therapeutic development due to their unique characteristics. GlcNAc is recognized primarily for its function as a precursor to hyaluronic acid, which plays a significant role in the structure and hydration of the extracellular matrix in skin, in both the epidermis and the dermis.

Objective: We investigated the protective effects of GlcNAc on immortalized human skin fibroblasts (HS68) against UVB damage.

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Background And Purpose: Capsaicin, a constituent of peppers, has been linked to the suppression of tumorigenesis and carcinogenesis. The influence of capsaicin on cytochrome P450 (CYP) 1A1, which is involved in metabolism of carcinogens, and the underlying mechanisms remain unclear. Here, we examined the effect of capsaicin on CYP1A1 expression in mouse hepatoma cells.

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The overexpression of metallothionein-2A (MT-2A) is frequently observed in invasive human breast tumors and has been linked with more aggressive breast cancers. MT-2A overexpression led to the induction of MDA-MB-231 breast cancer cell migratory and invasive abilities. The reduction of MT-2A expression through small interfering RNA (siRNA) targeting MT-2A in invasive MDA-MB-231 cells completely inhibited both cell invasion and migration.

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Scope: Acteoside, an active phenylethanoid glycoside found in bitter tea and many medicinal plants, displays chemopreventive properties. The aim of our study was to determine the effect of acteoside on tumor invasion and migration; the possible mechanisms involved in this inhibition were investigated in human fibrosarcoma HT-1080 cells.

Methods And Results: We employed invasion, migration and gelatin zymography assays to characterize the effect of acteoside on HT-1080 cells.

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Psidium guajava (P. guajava) is an important food crop and medicinal plant with antioxidant, anti-inflammatory, and anti-allergic activities, supporting its traditional uses. However, its precise effects remain unknown.

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Anthocyanins of the purple sweet potato exhibit antioxidant and hepatoprotective activities via a multitude of biochemical mechanisms. However, the signaling pathways involved in the actions of anthocyanin-induced antioxidant enzymes against chronic liver injury are not fully understood. We examined whether an anthocyanin fraction (AF) from purple sweet potato may prevent dimethylnitrosamine (DMN)-induced liver injury by inducing antioxidants via nuclear erythroid 2-related factor 2 (Nrf2) pathways and by reducing inflammation.

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Changkil (CK), the aqueous extract of the roots of Platycodon grandiflorum, has been used as a traditional oriental medicine for the treatment of chronic adult diseases. Although a saponin fraction derived from CK (CKS) has been suggested to have a variety of functional effects, its effect on bone is unknown. In the present study, the effects of CKS on osteoblast differentiation and function were determined by analyzing the activity of alkaline phosphatase (ALP), an osteoblast marker, and the regulation of RUNX2, a master gene of osteoblast differentiation, in a mesenchymal stem cell line.

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