Experimental and Therapeutic Medicine
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2021
·Vol. 22
·期 6
·1-10
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IF 2.447
Qian Li,Zhaoyan Qiu,Yan Wang,Chunyan Guo,Xu Cai,Yandong Zhang,Li Liu,Hongkun Xue,Jintian Tang
Tea polyphenols (TPs) are the major bioactive extract from green tea that have been extensively reported to prevent and treat oxidative stress damage. In previous studies, TPs have been demonstrated to protect cells against oxidative injury induced by hydrogen peroxide (H2O2). However, the underlying mechanism remains unclear. The aim of the current study was to investigate whether the protective and regulatory effects of TPs on oxidative stress damage were dependent on the mammalian STE20‑like protein kinase (Mst)/nuclear factor (erythroid‑derived 2)‑like 2 (Nrf2) axis and the Kelch‑like ECH‑associated protein 1 (Keap1)/Nrf2/heme oxygenase 1 (HO‑1) pathway in RAW264.7 cells, a murine macrophage cell line. Maintaining a certain range of intracellular reactive oxygen species (ROS) levels is critical to basic cellular activities, while excessive ROS generation can override the antioxidant capacity of the cell and result in oxidative stress damage. The inhibition of ROS generation offers an effective target for preventing oxidative damage. The results of the present study revealed that pretreatment with TPs inhibited the production of intracellular ROS and protected RAW264.7 cells from H2O2‑induced oxidative damage. TPs was also demonstrated to attenuate the production of nitric oxide and malondialdehyde and increase the levels of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase). In addition, following TPs treatment, alterations in Mst1/2 at the mRNA and protein level inhibited the production of ROS and promoted the self‑regulation of antioxidation. TPs‑induced Keap1 gene downregulation also increased the expression of Nrf2 and HO‑1. Collectively, the results of the present study demonstrated that TPs provided protection against H2O2‑induced oxidative injury in RAW264.7 cells.
研究领域:
药理学
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细胞生物学
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分子生物学
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生物化学
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DOI
PubMed
高影响因子
PHYTOMEDICINE
·
2024
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IF 6.7
Qichao Hu,Yuan Chen,Wenwen Zhang,Yubing Li,Xinyu Deng,Lisheng Chen,Zongyuan Zhou,Xiao Ma,Jinhao Zeng,Yanling Zhao
Background Acute gastric injury, a common and recurring global digestive disorder, significantly impairs patient quality of life and overall health. Dehydroevodiamine (DHE), a bioactive natural product derived from Tetradium ruticarpum ( A. Juss. ) Hartley, shows potential therapeutic effects on acute gastric injury. This study investigates the underlying mechanisms of DHE's alleviating effects on acute gastric injury. Methods The gastric mucosal protective effect of DHE was confirmed through in vivo and in vitro acute gastric injury models. Biotin pulldown MS and molecular dynamics simulations identified DHE's target. CETSA and SPR assays validated DHE's affinity for IKKβ. Protein site mutation validation and MST pinpointed the direct binding sites of DHE on IKKβ. Additionally, the potential mechanism by which DHE ameliorates acute gastric injury was elucidated using WB, IHC, and IF methods, and further confirmed by rescue experiments. Results DHE effectively ameliorated IDO-induced gastric injury in GES-1 cells and rat gastric mucosa, both in vitro and in vivo . Biotin pulldown MS identified IKKβ as the target of DHE in alleviating gastric injury. CETSA and SPR assays confirmed DHE's direct binding to IKKβ. Molecular dynamics simulations, protein mutation experiments, and MST results pinpointed GLU-149, GLU-49, and ASP-103 in the ATP-binding pocket as the binding sites of DHE on IKKβ. Notably, DHE was found to competitively bind to IKKβ with ATP. Mechanistically, DHE attenuated IDO-induced gastric injury by inhibiting the IKKβ-p65/NLRP3 signaling pathway. Importantly, exogenous activation of IKKβ reversed the therapeutic effect of DHE, indicating that DHE's efficacy depends on IKKβ. Conclusion DHE attenuated IDO-induced gastric injury by inhibiting the IKKβ-p65/NLRP3 signaling pathway. Notably, DHE is a novel ATP-competitive IKKβ inhibitor that prevents phosphorylation by targeting GLU-149, GLU-49, and ASP-103 in the ATP-binding pocket. This study reveals new targets of action for DHE, providing a new molecular basis for using DHE in treating inflammation-related diseases.
研究领域:
药理学
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胃肠病学
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分子生物学
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生物化学
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DOI
PubMed
高影响因子
Cell Chemical Biology
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2020
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IF 7.739
Giorgia Croppi,Yueyang Zhou,Rong Yang,Yunfei Bian,Mingtao Zhao,Youtian Hu,Benfang Helen Ruan,Jing Yu,Fang Wu
Summary H 2 S-producing enzymes in bacteria have been shown to be closely engaged in the process of microbial survival and antibiotic resistance. However, no inhibitors have been discovered for these enzymes, e.g., 3-mercaptopyruvate sulfurtransferase (MST). In the present study, we identified several classes of inhibitors for Escherichia coli MST (eMST) through high-throughput screening of ∼26,000 compounds. The thiazolidinedione-type inhibitors were found to selectively bind to Arg178 and Ser239 residues of eMST but hardly affected human MST. Moreover, the pioglitazone of this class concentration dependently accumulates the 3-mercaptopyruvate substrate and suppresses the H 2 S and reactive sulfane sulfur products in bacteria. Importantly, pioglitazone could potentiate the level of reactive oxygen species in cellulo and consequently enhance the antimicrobial effects of gentamicin and macrophages in culture. This study has identified the bioactive inhibitor of eMST, paving the way for the pharmacological targeting of eMST to synergistically control the survival of E. coli .
研究领域:
微生物学
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药理学
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细菌致病机制
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抗菌治疗
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DOI
PubMed
高影响因子
STAR Protocols
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2024
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IF 1.3
Shihao Song,Binbin Cui,Xiaohan Kong,Yinyue Deng
Summary Here, we present a protocol for identifying the components of a quorum sensing signaling system in bacteria. We describe the steps for characterizing the novel response regulator and receptor of the cis -2-dodecenoic acid (BDSF) quorum sensing signaling system in Burkholderia cenocepacia . The technical assays of this protocol include generating a random mutant library, chromatin immunoprecipitation sequencing (ChIP-seq), electrophoretic mobility transfer assay (EMSA), microscale thermophoresis (MST), and molecular simulation docking. For complete details on the use and execution of this protocol, please refer to Li et al. 1 and Yang et al. 2
研究领域:
微生物学
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分子生物学
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遗传学
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产品关联
DOI
PubMed
高影响因子
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