Publications by authors named "Yuan-Zhi Lao"

Autophagy plays a complex impact role in tumor initiation and development. It serves as a double-edged sword by supporting cell survival in certain situations while also triggering autophagic cell death in specific cellular contexts. Understanding the intricate functions and mechanisms of autophagy in tumors is crucial for guiding clinical approaches to cancer treatment.

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Background: Pyroptosis, an inflammatory form of programmed cell death (PCD), is reported to play important roles in the treatment of tumors. In our previous studies, we found that neobractatin (NBT), a caged prenylxanthone isolated from edible fruits of Garcinia bracteata C. Y.

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The fruits of can be eaten raw or processed into spices, which are considered to possess nutritional and medicinal value. Neobractatin (NBT) is a natural compound isolated from . This study showed that NBT showed antitumor effect by upregulation of CELF6.

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Article Synopsis
  • Mitophagy is a specific process of autophagy that removes damaged mitochondria and is significant for conditions like cardiovascular disease and neurodegenerative disorders.
  • This study identified garciesculenxanthone B (GeB), a new compound, that promotes mitophagy by stabilizing PINK1 and facilitating Parkin's movement to damaged mitochondria, leading to the degradation of certain mitochondrial proteins.
  • In mouse experiments, GeB showed potential in reducing brain injury caused by ischemia-reperfusion, indicating its role in enhancing the PINK1-Parkin-mediated mitophagy pathway for neuroprotection.
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A series of dearomatized isoprenylated acylphloroglucinols derivatives, hyperhenols A-E (1-5), as well as seven known analogues (6-12), were characterized from Hypericum henryi. Their structures were determined by combination of NMR, ECD spectroscopy, and X-ray diffraction analysis. Compounds 1 and 6-8 were tested to exhibit potential antitumor properties, of which 6 and 7 inhibited cell growth through inducing apoptosis and cell cycle arrest.

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  • Non-small-cell lung cancer (NSCLC) is the most common type of lung cancer and is influenced by a complex network of signals; existing therapies often fail due to drug resistance.
  • A study showed that combining the kinase inhibitors trametinib and bosutinib can work together to effectively inhibit the growth of NSCLC by targeting both the MAPK and SRC pathways.
  • This combo treatment was tested on various NSCLC cell lines, demonstrating strong anti-tumor effects and lower toxicity, providing a promising approach for tackling treatments that are resistant to erlotinib.
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  • Metastasis is a key factor in the lethality of esophageal cancer, and the natural compound garcinol has shown potential to inhibit this process through its properties as a histone acetyltransferase (HAT) inhibitor.
  • In experimental studies, garcinol significantly reduced the migration and invasion of esophageal cancer cell lines, suggesting it works by decreasing levels of key proteins like p300/CBP and p-Smad2/3, which are involved in tumor proliferation and metastasis.
  • Additionally, in a mouse model of pulmonary metastasis, treatment with garcinol led to a notable reduction in tumor nodules and markers of cell proliferation, highlighting its potential as a therapeutic agent against metastatic esophageal cancer.
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A global transcriptional regulator, MgrA, was previously identified as a key determinant of virulence in Staphylococcus aureus. An 80% EtOH extract of Uncaria gambier was found to attenuate the virulence of S. aureus via its effects on MgrA.

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  • Garsubelone A is a novel dimeric metabolite from Garcinia subelliptica, characterized by its complex heptacyclic structure with 10 stereogenic centers.
  • The compound is believed to be formed biogenetically from monomers garsubelone B and secohyperforin through a Diels-Alder cycloaddition, resulting in a unique nonane core.
  • Both compounds' structures and configurations were elucidated using advanced spectroscopic methods and X-ray diffraction, and their cytotoxic properties were tested.
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  • Lysosomes are crucial for breaking down cellular components through autophagy, and the natural compound oblongifolin C (OC) has been shown to increase autophagosomes while impairing lysosomal function.
  • The study found that OC enhances the nuclear movement of the transcription factor EB (TFEB), which regulates lysosomal activity, while simultaneously inhibiting mTORC1 and reducing TFEB's interaction with 14-3-3 proteins.
  • Despite OC's promotion of TFEB localization in the nucleus, it leads to reduced enzymatic activity in lysosomes and increased cell death in HeLa cells, indicating that OC disrupts lysosomal function rather than enhancing it.
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Autophagy, a form of cellular self-digestion by lysosome, is associated with various disease processes including cancers, and modulating autophagy has shown promise in the treatment of various malignancies. A number of natural products display strong antitumor activity, yet their mechanisms of action remain unclear. To gain a better understanding of how traditional Chinese medicine agents exert antitumor effects, we screened 480 natural compounds for their effects on autophagy using a high content screening assay detecting GFP-LC3 puncta in HeLa cells.

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Oblongifolin C (OC) and guttiferone K (GUTK) are two anticancer compounds extracted from Garcinia yunnanensis Hu, but they act by different mechanisms. In this study we investigated whether a combination of OC and GUTK (1:1 molar ratio) could produce synergistic anticancer effects against human colorectal cancer cells in vitro. For comparison, we also examined the anticancer efficacy of ethanol extracts from G yunnanensis fruit, which contain OC and GUTK up to 5%.

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A UPLC-PDA-QTOFMS-guided isolation strategy was employed to screen and track potentially new compounds from Garcinia oblongifolia. As a result, two new prenylated xanthones, oblongixanthones D and E (1-2), six new prenylated benzoylphloroglucinol derivatives, oblongifolins V-Z (3-7) and oblongifolin AA (8), as well as a known compound oblongifolin L (9), were isolated from the EtOAc-soluble fraction of an acetone extract of the leaves of Garcinia oblongifolia guided by UPLC-PDA-QTOFMS analysis. The structures of the new compounds were elucidated by 1D- and 2D-NMR spectroscopic analysis and mass spectrometry.

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Nujiangexathone A (NJXA), a novel compound derived from , has been demonstrated to inhibit the proliferation of several human cancer cell lines. This study is the first to demonstrate the apoptosis inductive activities of NJXA and the possible underlying mechanisms. Our results demonstrated that NJXA inhibited colony formation by HeLa and SiHa cells in a dose-dependent manner.

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Described is a facile helix-nucleating template based on a tethered aspartic acid at the N-terminus [terminal aspartic acid (TD)]. The nucleating effect of the template is subtly influenced by the substituent at the end of the side-chain-end tether as indicated by circular dichroism, nuclear magnetic resonance, and molecular dynamics simulations. Unlike most nucleating strategies, the N-terminal amine is preserved, thus enabling further modification.

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Garcinia Linn. plants having rich natural xanthones and benzophenones with anti-inflammatory activity attracted a great deal of attention to discover and develop them as potential drug candidates. Through screening targeting nitric oxide accumulation in stimulated macrophage, we found that 1,3,5,7-tetrahydroxy-8-isoprenylxanthone (TIE) had potential anti-inflammatory effect.

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Hypersubones A and B (1, 2), two adamantane type polycyclic polyprenylated acylphloroglucinols possessing an unprecedented seco-adamantane architecture and a tetracyclo-[6.3.1.

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Five new prenylated benzoylphloroglucinol derivatives, garciesculentones A-E (1-5), a new xanthone, garciesculenxanthone A (6), and 15 known compounds were isolated from the petroleum ether extract and the EtOAc-soluble fraction of a 80% (v/v) EtOH extract of Garcinia esculenta. The structures of the new compounds were elucidated by 1D- and 2D-NMR spectroscopic analysis and mass spectrometry. Experimental and calculated ECD and a convenient modified Mosher's method were used to determine the absolute configurations.

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Bioassay-guided fractionation of the acetone extract of the leaves of Garcinia nujiangensis resulted in the isolation of two new prenylated xanthones, nujiangexanthones A (1) and B (2), three new polycyclic polyprenylated acylphloroglucinols, nujiangefolins A-C (3-5), and 10 known related analogues. The structures of compounds 1-5 were elucidated by interpretation of their spectroscopic data. Compounds 3 and 4 are unusual polycyclic polyprenylated acylphloroglucinols in which the enol hydroxy group forms a six-membered ring with a benzene ring carbon.

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We have recently reported that bis(7)-tacrine could prevent glutamate-induced neuronal apoptosis through NMDA receptors. In this study, we demonstrated that in cultured rat cortical neurons, bis(7)-tacrine (IC(50), 0.02 microM) prevented glutamate-induced excitotoxicity more substantially than memantine (IC(50), 0.

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An ultrasensitive nucleic acid biosensor for direct detection of genes in mRNA extracted from animal tissues is described. It is based on amperometric detection of a target gene by forming an mRNA/redox polymer bilayer on a gold electrode. The mRNA was directly labeled with cisplatin-biotin conjugates through coordinative bonds with purine bases in the mRNA molecules.

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