Vet Immunol Immunopathol. 2014 May 15;159(1-2):50-7. |
Inhibitory effects of α-cyperone on adherence and invasion of avian pathogenic Escherichia coli O78 to chicken type II pneumocytes.[Pubmed: 24629766] |
METHODS AND RESULTS:
Avian pathogenic Escherichia coli (APEC) are extra-intestinal pathogenic E. coli, and usually cause avian septicemia through breaching the blood-gas barrier. Type II pneumocytes play an important role of maintaining the function of the blood-gas barrier. However, the mechanism of APEC injuring type II pneumocytes remains unclear. α-cyperone can inhibit lung cell injury induced by Staphylococcus aureus. In order to explore whether α-cyperone regulates the adherence and invasion of APEC-O78 to chicken type II pneumocytes, we successfully cultured chicken type II pneumocytes.
CONCLUSIONS:
The results showed that α-cyperone significantly decreased the adherence of APEC-O78 to chicken type II pneumocytes. In addition, α-cyperone inhibited actin cytoskeleton polymerization induced by APEC-O78 through down regulating the expression of Nck-2, Cdc42 and Rac1. These results provide new evidence for the prevention of colibacillosis in chicken.
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J Microbiol Biotechnol. 2012 Aug;22(8):1170-6. |
α-cyperone alleviates lung cell injury caused by Staphylococcus aureus via attenuation of α-hemolysin expression.[Pubmed: 22713997] |
METHODS AND RESULTS:
In this study, we aimed to evaluate the effect of α- cyperone on S. aureus. We used a hemolysin test to examine the hemolytic activity in supernatants of S. aureus cultured with increasing concentrations of α- cyperone. In addition, we evaluated the production of α- hemolysin (Hla) by Western blotting. Real-time RT-PCR was performed to test the expression of hla (the gene encoding Hla) and agr (accessory gene regulator). Furthermore, we investigated the protective effect of α- cyperone on Hla-induced injury of A549 lung cells by live/ dead and cytotoxicity assays. We showed that in the presence of subinhibitory concentrations of α-cyperone, Hla production was markedly inhibited. Moreover, α- cyperone protected lung cells from Hla-induced injury.
CONCLUSIONS:
These findings indicate that α-cyperone is a promising inhibitor of Hla production by S. aureus and protects lung cells from this bacterium. Thus, α-cyperone may provide the basis for a new strategy to combat S. aureus pneumonia. |
J Ethnopharmacol . 2016 Dec 24;194:219-227. |
α-Cyperone of Cyperus rotundus is an effective candidate for reduction of inflammation by destabilization of microtubule fibers in brain[Pubmed: 27353867] |
Abstract
Ethnopharmacological relevance: Cyperus rotundus L. (Cyperaceae), commonly known as purple nutsedge or nut grass is one of the most invasive and endemic weeds in tropical, subtropical and temperate regions. This plant has been extensively used in traditional medicine for anti-arthritic, antidiarrheal and antiplatelet properties as well as treatment for several CNS disorders such as epilepsy, depression and inflammatory disorders. Inflammation is evidently occurring in pathologically susceptible regions of the Alzheimer's disease (AD) brain as well as other disorders. Many cellular processes are responsible in chronic inflammation. Microtubule-based inflammatory cell chemotaxis is a well-recognized process that influences production of cytokines and phagocytosis. The effect of α-Cyperone, one of main ingredients of Cyperus rotundus on microtubule assembly and dynamics has not been examined and is the purpose of this investigation.
Materials and methods: Microtubules and tubulin were extracted in order to explore their interaction with α-Cyperone by utilization of turbidimetric examinations, intrinsic fluorescence and circular dichroism spectroscopy (CD) studies. The molecular docking analysis was executed in order to facilitate a more detail and stronger evidence of this interaction. The BINding ANAlyzer (BINANA) algorithm was used to evaluate and further substantiate the binding site of α-Cyperone.
Results: It was demonstrated that α-Cyperone had a pronounced influence on the tubulin structure, decreased polymerization rate and reduced concentration of polymerized tubulin in vitro. The CD deconvolution analysis concluded that significant conformational changes occurred, demonstrated by a drastic increase in content of β-strands upon binding of α-Cyperone. The fluorescence spectroscopy revealed that a static type of quenching mechanism is responsible for binding of α-Cyperone to tubulin. Upon characterization of various biophysical parameters, it was further deduced that ligand binding was spontaneous and a single site of binding was confirmed. Transmission electron microscopy revealed that upon binding of α-Cyperone to microtubule the number and complexity of fibers were noticeably decreased. The computational analysis of docking suggested that α-Cyperone binds preferably to β-tubulin at a distinct location with close proximity to the GTP binding and hydrolysis site. The ligand interaction with β-tubulin is mostly hydrophobic and occurs at amino acid residues that are exclusively on random coil. The BINANA 1.2.0 algorithm which counts and tallies close molecular interaction by performing defined set of simulations revealed that amino acid residues Arg 48 and Val 62 have registered the highest scores and are possibly crucial in ligand-protein interaction.
Conclusion: α-Cyperone binds and interacts with tubulin and is capable of distinctly destabilizing microtubule polymerization. The effect of this interaction could result in reduction of inflammation which would be highly beneficial for treatment of inflammatory diseases such as AD.
Keywords: ATP (PubChem CID: 5957); GTP (PubChem CID: 6830); Microtubule polymerization; Molecular docking; Rhizomes of Cyperus rotundus; Tubulin; α-Cyperone; α-Cyperone (PubChem CID: 6452086). |