Publications by authors named "Ming-bao Lin"

Rosmarinic acid (RosA), a hydrophilic phenolic compound found in various plants, has several biological effects such as anti-inflammatory and anti-apoptosis activities. However, its potential impact on chronic obstructive pulmonary disease (COPD) and its underlying mechanism has not been investigated. In this study, we explored the potential therapeutic effects and mechanism of RosA on COPD airway inflammation and alveolar epithelial apoptosis and .

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Six undescribed compounds, including three phenolic glycosides (1-3) and three indole alkaloids (4-6), together with ten known alkaloids (7-16) and three known phenolic glycosides (17-19), were isolated from 70% EtOH aqueous extracts of the roots and rhizomes of Clematis chinensis Osbeck. The structures were elucidated by NMR, HRESIMS and X-ray diffraction spectroscopies. The anti-inflammatory activity of these compounds was evaluated, and twelve compounds showed significant inhibitory activity against TNF-α with an inhibition ratio from 47.

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A full set of 8,4'-oxy-8'-phenylneolignans with four chiral carbons, named (+)/(-)-leptolepisols D1‒D2 and (+)/(-)-sophorols A‒F, were isolated from the roots and rhizomes of Sophora tonkinensis Gagnep., including 14 previously undescribed stereoisomers, along with 2 known leptolepisol D diastereomers. Their planar structures and relative configurations were elucidated by detailed spectroscopic analysis (HRESIMS and NMR).

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Two new prenylaromadendrane-type diterpenoids, and three known analogues, were isolated from the ethanol extract of the gum resin of Flueck. The structures of the new compounds were elucidated using 1 D and 2 D NMR spectroscopic analyses, mass spectrometric data, circular dichroism spectra, and comparison with the other compounds in the literature. One diterpenoid represents the first example of an acetoxyl-substituted prenylaromadendranoid in frankincense.

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(L.) Britton is a classic herbal plant used widely against asthma in China. But its mechanism of beneficial effect remains undermined.

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Three previously unidentified polycyclic polyprenylated acylphloroglucinols (PPAPs) derivatives, hypseudohenrins I-K (-), along with a known analogue hyphenrone X (), were isolated from the aerial part of . The structures of the new compounds were elucidated by NMR spectroscopy and ECD calculation. The anti-inflammatory activity of the compounds was evaluated.

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Two new hydroxylated ethacrylic acid derivatives (compounds and ) and 11 new hydroxylated tiglic acid derivatives (compounds -), together with one known compound (compound ), were isolated from the stems and branches of . Their structures were established by extensive spectroscopic analyses, while their absolute configurations were determined by X-ray crystallographic methods (compounds and ), Mo(OAc)-induced electronic circular dichroism experiments (compounds and ), and chemical methods (compounds -). This study is the first investigation on the secondary metabolites of this species.

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Nine 14,15-secopregnane-type C-steriosides, stauntosides U, V, V-V, W and C-C, as well as two known C-steriosides, were isolated from the roots of Cynanchum stauntonii. Stauntosides U, V and V-V share the same basic structural features of 8α:14α,14:16,15:20,18:20-tetraepoxy-14,15-secopregn-6-ene-3β,5α,9α-triol, with the numbering system following that of C-pregnanes. The aglycones of stauntosides U, V and V-V are classified into two subcategories, the 5,9-dihydroxy groups and 5α:9α-peroxy bridge, according to the oxidative states of the two hydroxy groups at the C-5 and C-9 positions.

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Inflammation derived from macrophages activation leads to various diseases. Synthetic modifications of resveratrol have been shown to have better anti-inflammatory activities. In this study, croton oil-induced mouse ear edema and lipopolysaccharides (LPS)-stimulated RAW264.

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Nuclear factor-erythroid 2 related factor 2 (Nrf2) is an ubiquitous and important transcription factor. It regulates antioxidant response elements (AREs)-mediated expression of antioxidant enzyme and cytoprotective proteins. A large body of research showed that Nrf2-Keap1 (Kelch-like ECH-associated protein 1, Keap 1)-ARE signaling pathway is involved in the endogenous antioxidant defense mechanisms.

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Twelve hydrolyzable tannins were obtained from the twigs of Myricaria bracteata, including two new hellinoyl-type dimers, bracteatinins D1 (1) and D2 (2); a new hellinoyl-type trimer, bracteatinin T1 (3); two known monomers, nilotinin M4 (4) and 1,3-di-O-galloyl-4,6-O-(aS)-hexahydroxydiphenoyl-β-d-glucose (5); six known dimers, tamarixinin A (6), nilotinin D8 (7), hirtellins A (10), B (9), and E (8), and isohirtellin C (11); and a known trimer, hirtellin T3 (12). The structures of the tannins were elucidated by spectroscopic data analysis and comparisons to known tannins. All compounds were evaluated as free radical scavengers using 1,1-diphenyl-2-picrylhydrazyl and hydroxy radicals and compared to the activity of BHT and Trolox.

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Synthetic isorhapontigenin was treated with several kinds of inorganic reagents and peroxidase so as to prepare active stilbene dimers. Among them, silver acetate in methanol gave two new isorhapontigenin dimers 4 and 5, together with four known natural stilbene dimers 2, 3, 6, and 7. Their structures and relative configurations were determined on the basis of spectral analysis, and their possible formation mechanisms were discussed, respectively.

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