Publications by authors named "Tian-Tai Zhang"

Scope: Quercetin (QU) is one of the most abundant flavonoids in plants and has attracted the attention of researchers because of its remarkable antirheumatoid arthritis (RA) effects and extremely low adverse reactions. However, the underlying mechanism needs further study.

Methods And Results: Flow cytometry, immunofluorescence, enzyme linked immunosorbent assay (ELISA), and quantitative real-time polymerase chain reaction (qRT-PCR) reveal the obvious inhibitory effects of QU on Th17 cell differentiation in arthritic mice.

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Background: Chronic neuropathic pain is a frequent sequel to peripheral nerve injury and maladaptive nervous system function. Divanillyl sulfone (DS), a novel structural derivative of 4,4'-dihydroxydibenzyl sulfoxide from a traditional Chinese medicine Gastrodia elata with anti-nociceptive effects, significantly alleviated neuropathic pain following intrathecal injection. Here, we aimed to investigate the underlying mechanisms of DS against neuropathic pain.

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Five new denudatine-type diterpenoid alkaloids (1-5), along with the known analogue aconicarmine (), were isolated from an aqueous decoction of the lateral roots of (fu-zi). Their structures were determined by spectroscopic data analysis and electronic circular dichroism (ECD) calculations. Compound is the first denudatine-type diterpenoid alcohol iminium alkaloid, which could be partially transformed into the aza acetal form in pyridine-.

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Six new triterpenes, uncarinic acids KP (), along with 24 known analogues, were isolated as minor constituents of an aqueous decoction of the hook-bearing stems of (Gou-teng). By comprehensive spectroscopic data analysis, their structures were elucidated as derivatives of olean-12-en-28-oic acid and urs-12-en-28-oic acid with different oxidized forms at C-3, C-6, and/or C-23, respectively. Cell-based preliminary bioassay showed that the ()-/()-coumaroyloxy and ()-/()-feruloyloxy units at C-27 of olean-12-en-28-oic acid and urs-12-en-28-oic acid played roles in their bioactivities.

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Selective JAK3 inhibitors have been shown to have a potential benefit in the treatment of autoimmune disorders. Here we report the identification of a series of pyrazolopyrimidine derivatives as potent JAK3 inhibitors that exploit a unique cysteine (Cys909) residue in JAK3. Most of these compounds (13k, 13n and 13 t), displayed stronger anti-JAK3 kinase activity and selectivity than tofacitinib.

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Janus kinases (JAKs) play a key role in the proliferation, apoptosis and differentiation of immune cells, and JAKs are considered as an attractive target for the treatment of inflammatory and autoimmune diseases. Here we show the design and optimization of pyrimidine-4,6-diamine derivatives as selectivity JAK3 inhibitors. Compound 11e, which might interact with unique cysteine (Cys909) residue in JAK3, exhibited excellent JAK3 inhibitory activity (IC = 2.

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Janus kinases (JAKs) regulate various cancers and immune responses and are targets for the treatment of cancers and immune diseases. A new series of 1H-pyrazolo[3,4-d]pyrimidin-4-amino derivatives were synthesized and optimized by introducing a functional 3,5-disubstituted-1H-pyrazole moiety into the C-3 moiety of pyrazole template, and then were biologically evaluated as potent Janus kinase 2 (JAK2) inhibitors. Among these molecules, inhibitors 11f, 11g, 11h and 11k displayed strong activity and selectivity against the JAK2 kinase, with IC values of 7.

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Histamine H receptor (HR), a kind of G-protein coupled receptor (GPCR), is expressed mainly in the central nervous system (CNS) and plays a vital role in homoeostatic control. This study describes the design and synthesis of a series of novel HR antagonists based on the iso-flavone scaffold. The results of the bioactivity evaluation show that four compounds (1c, 2c, 2h, and 2o) possess significant HR inhibitory activities.

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Janus kinases (JAKs) regulate various inflammatory and immune responses and are targets for the treatment of inflammatory and immune diseases. Here we report the discovery and optimization of 1H-pyrazolo[3,4-d]pyrimidin-4-amino as covalent JAK3 inhibitors that exploit a unique cysteine (Cys909) residue in JAK3. Our optimization study gave compound 12a, which exhibited potent JAK3 inhibitory activity (IC of 6.

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Aims: Alzheimer's disease (AD) is an incurable neurodegenerative disorder characterized by global cognitive impairment that involves accumulation of amyloid-beta peptides (Aβ) in the brain. Herbal approaches can be used as alternative medicines to slow the progression of AD. This study aimed to determine the beneficial effects and potential underlying mechanisms of total flavonoid extract from Dracoephalum moldavica L.

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Rhodoterpenoids A‒C (1‒3), three new rearranged triterpenoids, together with one new biogenetically related compound, rhodoterpenoid D (4), were isolated and efficiently elucidated from Rhododendron latoucheae by high-performance liquid chromatography-mass spectrometry-solid-phase extraction-nuclear magnetic resonance (HPLC‒MS‒SPE‒NMR). Compounds 1 and 2 possess an unprecedented skeleton with a 5/7/6/6/6-fused pentacyclic ring system, while compound 3 contains a unique 6/7/6/6/6-fused pentacyclic carbon backbone. Their structures were determined by extensive spectroscopic methods and electronic circular dichroism (ECD) analyses.

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Shenqi is a traditional Chinese polyherbal medicine has been widely used for the treatment of allergic rhinitis (AR). The aim of this study was to investigate the anti-allergic rhinitis activity of Shenqi and explore its underlying molecular mechanism. Ovalbumin (OVA)-induced allergic rhinitis rat model was used to evaluate the anti-allergic rhinitis effect of Shenqi.

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JAK-3, a member of the Janus kinase family, is a protein tyrosine kinase, which plays an important role in the JAK-STAT signaling pathway. Previous studies showed that regulation of JAK-3’s activity plays a crucial role in the treatment of diseases such as rheumatoid arthritis. Many reports have been published with a focus on selective JAK-3 inhibitors, some of which showed excellent JAK-3 selectivity and inhibitory activities.

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Two new megastigmane glycosides, named wilfordonisides A and B (1 and 2), and four known compounds (3-6) were isolated from the leaves of Tripterygium wilfordii, and one new aglycon, named wilfordoninol A (2a), was acquired by enzymatic hydrolysis of 2. The absolute stereostructures of the compounds were determined by Mosher's method and by CD. At a concentration of 10 μM, compounds 1, 3, and 5 inhibited STAT1 translocation by 38.

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Four new norsesquiterpenes wilfordonols A-D (1-4), along with three known compounds, sarmentol B (5), boscialin (6), and (+)-loliolide (7), were isolated from the leaves of Tripterygium wilfordii Hook.f..

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Neuropathological, clinical epidemiology and animal models studies provide clear evidence for the activation of neuroinflammation in Alzheimer's disease (AD), and long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) is linked with reduced risk to develop the disease. But the clinical trials got a negative outcome with traditional NSAIDs treating AD. The therapeutic effects of NSAIDs on Alzheimer's disease are still not clear based on the present research.

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Cerebrovascular accumulation of amyloid-β (Aβ) peptides in Alzheimer's disease (AD) may contribute to disease progression through Aβ-induced microvascular endothelial pathogenesis. Pinocembrin has been shown to have therapeutic effects in AD models. These effects correlate with preservation of microvascular function, but the effect on endothelial cells under Aβ-damaged conditions is unclear.

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Amyloid-β (Aβ) peptides accumulate in the brain and initiate a cascade of pathologic events in Alzheimer's disease. The receptor for advanced glycation end products (RAGE) has been implicated to mediate Aβ-induced perturbations in the neurovascular unit (NVU). We demonstrated that pinocembrin exhibits neuroprotection through inhibition of the Aβ and/or RAGE pathway, but the therapeutic role and mechanism involved are not ascertained.

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Quercetin has demonstrated protective effects against Aβ-induced toxicity on both neurons and endothelial cells. However, whether or not quercetin has an effect on the neurovascular coupling is unclear. In the present study, we aim to investigate the anti-amnesic effects of quercetin and to explore the underlying mechanisms.

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Background: It is known that amyloid-β peptide (Aβ) plays a pivotal role in the pathogenesis of Alzheimer's disease (AD). Interaction between Aβ and the receptor for advanced glycation end products (RAGE) has been implicated in neuronal degeneration associated with this disease. Pinocembrin, a flavonoid abundant in propolis, has been reported to possess numerous biological activities beneficial to health.

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The synthesis of gaultherin (1) and its analogs was carried out to provide 11 glycosides under phase-transfer catalytic conditions. The activities of all synthesized compounds were evaluated by nitric oxide production inhibitory assay in vitro. Methyl 2-O-(4-O-β-d-galactopyranosyl)-β-d-glucopyranosylbenzoate (5f) showed significantly anti-nociceptive and anti-inflammatory effects by the evaluation in vivo.

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Alzheimer's disease involves the complex and interconnected cascade of cellular and molecular events. Only a few treatments are available to slow the course of the disease at present. Recent studies suggest that neurovascular unit serves to maintain cerebral homeostasis, and pathological interactions between components of neurovascular unit lead to cerebral dysfunction.

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Gaultheria yunnanensis (Franch.) Rehder is a kind of traditional Chinese herbal medicine used for the treatments of rheumatoid arthritis, swelling and pain. Two methyl salicylate glycosides, namely methyl benzoate-2-O-β-D-xylopyranosyl(1-6)-O-β-D-gluco-pyranoside (J12122) and methyl benzoate-2-O-β-D-xylopyranosyl(1-2)[O-β-D-xylopyranosyl(1-6)]-O-β-D-glucopyranoside (J12123), are natural salicylic derivatives isolated from Gaultheria yunnanensis.

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1. The aim of the present study was to explore the effects of CPU0213, a dual endothelin ET(A)/ET(B) receptor antagonist, and nifedipine, a calcium antagonist, in relieving pulmonary hypertension (PH). Both endothelin receptor and calcium antagonists have been reported to be effective in alleviating the remodelling of pulmonary arteries induced by monocrotaline (MCT) in rats.

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