Anti-Cytokine Activity of Curcumin and Its Binding to a Fragment of AβPP
Victoria V. Sokolik,
Pavel A. Karpov,
Dariya A. Samofalova,
Sergiy M. Shulga
Issue:
Volume 4, Issue 4, August 2016
Pages:
34-46
Received:
19 May 2016
Accepted:
2 June 2016
Published:
20 June 2016
Abstract: Since it has been shown that Alzheimer’s disease is accompanied by higher peripheral concentrations of cytokines, we focused on the correction of chronic inflammation causing Aβ excess and aggregation what should have a positive impact. Proinflammatory cytokines action is realized by NF-κB intracellular signals. Curcumin can inhibit activation of the proinflammatory transcription factor NF-κB and is able to be mounted in the amyloid-β fibrils and encourage their disaggregation. To study the influence of anti-inflammatory effect of curcumin and its ability to model complexes with a fragment of AβPP. Investigation was carried out on rats with model of Alzheimer’s disease using nasal therapy with curcumin Concentration of cytokines in cerebral cortex, hippocampus and blood serum, and indicators of conditioned active escape reflex were determined in this study. Methods of molecular dynamics and docking were used to examine the interactions of curcumin with fragment of AβPP. Аβ42_Human in the hippocampus of rats provoked chronic neuroinflammation specifically and primarily at the injection site. Curcumin performance revealed specific depressing effect on cytokines in the cerebral cortex and in the hippocampus it appeared similar to the above, but of lower level. Anti-inflammatory activity of curcumin led to the recovery of memory parameters. Analysis of restriction sites of AβPP has shown that position of curcumin in Site II is energetically more favorable for binding. Our suggestion that curcumin is an effective anti-cytokine factor was confirmed by experimental results obtained in vivo and explain the mechanism describing its effect on NF-κB Curcumin doesn’t block the excision Aβ but binding with its hydrophobic region.
Abstract: Since it has been shown that Alzheimer’s disease is accompanied by higher peripheral concentrations of cytokines, we focused on the correction of chronic inflammation causing Aβ excess and aggregation what should have a positive impact. Proinflammatory cytokines action is realized by NF-κB intracellular signals. Curcumin can inhibit activation of t...
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Isolation, Partial Purification and Characterization of Polyphenol Oxidase from Two Species of African Mango Seeds (Irvingia gabonensis and Irvingia wombolu)
Issue:
Volume 4, Issue 4, August 2016
Pages:
47-52
Received:
16 May 2016
Accepted:
26 May 2016
Published:
30 June 2016
Abstract: Polyphenol oxidases are oxido-reductases that catalyses oxidation of phenolic compounds in the presence of oxygen to form corresponding quinone intermediates which spontaneously polymerize to form undesirable pigments. Polyphenol oxidase was isolated and characterized in Irvingia species (gabonensis and wombolu) kernel, a tropical African fruit. Extracts were partially purified with ammonium sulphate. The effects of optimum pH and temperature were investigated while the pH and thermal stability were carried out. The Km, Vmax and the activity on both monophenol and diphenol substrates were determined. The optimum pH and optimum temperature of activity were found out to be 7.0 and 60°C in both species. The enzyme was stable at pH 7.0 and pH 8.0, and also at temperatures of 25, 30, 40, 50 and 60°C, it however loses stability beyond 60°C. Km and Vmax for Irvingia gabonesis were 2.51mM and 0.0411 Unit/min while Km and Vmax for Irvingia wombolu were 2.55mM and 0.0415 Unit/min respectively. Higher activity was observed with diphenol substrate L-DOPA than with monophenol - tyrosine. It can therefore be deduced from this study that the storage of the seeds of African mango at a room temperature above 60°C will prolong its shelf-life.
Abstract: Polyphenol oxidases are oxido-reductases that catalyses oxidation of phenolic compounds in the presence of oxygen to form corresponding quinone intermediates which spontaneously polymerize to form undesirable pigments. Polyphenol oxidase was isolated and characterized in Irvingia species (gabonensis and wombolu) kernel, a tropical African fruit. Ex...
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