Publications by authors named "Sei Ryang Oh"

Allergic asthma is a major health burden on society as a chronic respiratory disease characterized by inflammation and muscle tightening around the airways in response to inhaled allergens. Daphne kiusiana Miquel is a medicinal plant that can suppress allergic airway inflammation; however, its specific molecular mechanisms of action are unclear. In this study, we aimed to elucidate the mechanisms by which D.

View Article and Find Full Text PDF

Isoscopoletin is a compound derived from various plants traditionally used for the treatment of skin diseases. However, there have been no reported therapeutic effects of isoscopoletin on atopic dermatitis (AD). AD is a chronic inflammatory skin disease, and commonly used treatments have side effects; thus, there is a need to identify potential natural candidate substances.

View Article and Find Full Text PDF

Idiopathic pulmonary fibrosis (IPF) is a chronic and refractory interstitial lung disease. Although there is no cure for IPF, the development of drugs with improved efficacy in the treatment of IPF is required. Daphnetin, a natural coumarin derivative, has immunosuppressive, anti-inflammatory, and antioxidant activities.

View Article and Find Full Text PDF

Since the ethanol extract of Juzepzuk (EEAO) suppresses lung inflammation by suppressing Nuclear Factor-kappa B (NF-κB) and activating Nuclear Factor Erythroid 2-related Factor 2 (Nrf2), we set out to identify chemicals constituting EEAO that suppress lung inflammation. Here, we provide evidence that among the five most abundant chemical constituents identified by Ultra Performance Liquid Chromatography (UPLC) and Nuclear Magnetic Resonance (NMR), alismol is one of the candidate constituents that suppresses lung inflammation in a lipopolysaccharide (LPS)-induced acute lung injury (ALI) mouse model and protects mice from ALI-like symptoms. Alismol did not induce cytotoxicity or reactive oxygen species (ROS).

View Article and Find Full Text PDF

Affinity-based ultrafiltration-mass spectrometry coupled with ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry was utilised for the structural identification of direct tyrosinase ligands from a crude var. extract. False positives were recognised by introducing time-dependent inhibition in the control for comparison.

View Article and Find Full Text PDF

Purpose: Pseudognaphalium affine (P. affine), a medicinal plant, has long been used to treat various diseases due to its astringent and vulnerary effects. These therapeutic benefits are largely attributed to high contents of phytochemicals, such as flavonoids and polyphenols, that have anti-inflammatory and tissue-protective activities.

View Article and Find Full Text PDF

The renin-angiotensin (RA) system has been implicated in lung tumorigenesis without detailed mechanistic elucidation. Here, we demonstrate that exposure to the representative tobacco-specific carcinogen nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) promotes lung tumorigenesis through deregulation of the pulmonary RA system. Mechanistically, NNK binding to the nicotinic acetylcholine receptor (nAChR) induces Src-mediated signal transducer and activator of transcription 3 (STAT3) activation, resulting in transcriptional upregulation of angiotensinogen (AGT) and subsequent induction of the angiotensin II (AngII) receptor type 1 (AGTR1) signaling pathway.

View Article and Find Full Text PDF

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease which causes breathing problems. YPL-001, consisting of six iridoids, has potent inhibitory efficacy against COPD. Although YPL-001 has completed clinical trial phase 2a as a natural drug for COPD treatment, the most effective iridoid in YPL-001 and its mechanism for reducing airway inflammation remain unclear.

View Article and Find Full Text PDF

Unlabelled: Pulmonary emphysema is a destructive inflammatory disease primarily caused by cigarette smoking (CS). Recovery from CS-induced injury requires proper stem cell (SC) activities with a tightly controlled balance of proliferation and differentiation. Here we show that acute alveolar injury induced by two representative tobacco carcinogens, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone and benzo[a]pyrene (N/B), increased IGF2 expression in alveolar type 2 (AT2) cells to promote their SC function and facilitate alveolar regeneration.

View Article and Find Full Text PDF

The type three secretion system (T3SS) is a major virulence system of (). The effector protein Exotoxin S (ExoS) produced by is secreted into the host cells via the T3SS. For the purpose of an experiment on inhibitors with regard to ExoS secretion, we developed a sandwich-type enzyme-linked immunosorbent assay (ELISA) system.

View Article and Find Full Text PDF

Idiopathic pulmonary fibrosis (IPF) is a chronic and refractory interstitial lung disease. Although there are two approved drugs for IPF, they were not able to completely cure the disease. Therefore, the development of new drugs is required for the effective treatment of IPF.

View Article and Find Full Text PDF

Skullcapflavone II (SFII), a flavonoid derived from , is an anticancer agent. We aimed to validate SFII for atopic dermatitis (AD) therapy by demonstrating the anti-inflammatory effects of SFII in an AD mouse model produced by the topical application of the vitamin D3 analog MC903. We showed that topical treatment with SFII significantly suppressed MC903-induced serum IgE levels compared with topical hydrocortisone (HC) treatment.

View Article and Find Full Text PDF

Methyl p-coumarate (methyl p-hydroxycinnamate) (MH) is a natural compound found in a variety of plants. In the present study, we evaluated the ameliorative effects of MH on airway inflammation in an experimental model of allergic asthma (AA). In this in vitro study, MH was found to exert anti-inflammatory activity on PMA-stimulated A549 airway epithelial cells by suppressing the secretion of IL-6, IL-8, MCP-1, and ICAM-1.

View Article and Find Full Text PDF

The bioactive components of (Thunb.) DC pods were investigated using bioactivity-guided isolation, and the chemical structures of flavonoids -, isoflavonoid derivatives -, and phenolic compounds and were identified by comparing NMR, MS, and CD spectral data with previously reported spectroscopic data. Compounds - were evaluated for their anti-inflammatory effects on LPS-stimulated RAW264.

View Article and Find Full Text PDF

Objective: We investigated whether purpurin inhibits various pathways of inflammation leading to atopic dermatitis.

Introduction: 1,2,4-Trihydroxyanthraquinone, commonly called purpurin, is an anthraquinone that is a naturally occurring red/yellow dye. Purpurin is a highly antioxidative anthraquinone and previous studies have reported antibacterial, anti-tumor, and anti-oxidation activities in cells and animals.

View Article and Find Full Text PDF

Kurarinone (KR), a naturally occurring flavonoid in Sophora flavescens Aiton and a traditional herbal medicine, reportedly has anti-cancer activity against various cancer types both in vitro and in vivo. However, the cellular mechanism of KR remains unknown. Therefore, we aimed to elucidate the mechanism of cell cycle arrest induced by KR in human colorectal cancer cells.

View Article and Find Full Text PDF

Background: Since long-term or high-dose use of COPD medication causes adverse effects in patients with COPD, more effective and safer ways to manage COPD symptoms are required. Daphne kiusiana Miquel is a medicinal plant, but its anti-COPD efficacy was little studied.

Purpose: We investigated the anti-COPD activity and molecular mechanism of action of active compounds isolated from D.

View Article and Find Full Text PDF

Teijsm. & Binn. (LO) (crape myrtle) has reportedly been used as traditional herbal medicine (THM) in Java, Indonesia.

View Article and Find Full Text PDF

Idiopathic pulmonary fibrosis (IPF) is a refractory interstitial lung disease for which there is no effective treatment. Although the pathogenesis of IPF is not fully understood, TGF-β and epithelial-mesenchymal transition (EMT) have been shown to be involved in the fibrotic changes of lung tissues. Kurarinone is a prenylated flavonoid isolated from with antioxidant and anti-inflammatory properties.

View Article and Find Full Text PDF

Ethnopharmacological Relevance: Vernicia fordii (Hemsl.) Airy Shaw (V. fordii) is also known as the tung tree and its leaves and fruit are used as an oriental treatment for dyspepsia, edema, and skin diseases, which are known as diabetic complications.

View Article and Find Full Text PDF

3,4,5‑Trihydroxycinnamic acid (THCA) exhibits anti‑inflammatory activity in acute or chronic inflammatory disorders, such as acute lung injury and asthma. The present study investigated the anti‑inflammatory activity of THCA in a tumor necrosis factor‑α/interferon‑γ (TI) mixture‑stimulated human keratinocyte cell line. The results of ELISA and reverse transcription‑quantitative PCR revealed that THCA reduced the secretion and mRNA expression levels of interleukin (IL)‑6; IL‑8; thymus and activation‑regulated chemokine; macrophage‑derived chemokine; regulated upon activation, normal T cell expressed and secreted; and monocyte chemoattractant protein‑1 in TI mixture‑stimulated HaCaT cells.

View Article and Find Full Text PDF