Morphological and chemical changes in the trophozoites and cysts of Acanthamoeba castellanii induced by Camellia sinensis extracts

Tools

Fakae, LB, Zhong, J, Chan, KLA, Mekapothula, S ORCID: https://orcid.org/0000-0002-3906-842X, Cave, GWV ORCID: https://orcid.org/0000-0002-4167-1332, Zhu, X-Q, Stevenson, CW and Elsheikha, HM, 2025. Morphological and chemical changes in the trophozoites and cysts of Acanthamoeba castellanii induced by Camellia sinensis extracts. Acta Parasitologica, 70 (2): 63. ISSN 1230-2821

Preview

Text
2395582_Cave.pdf - Published version
Download (4MB) | Preview

Official URL: https://doi.org/10.1007/s11686-024-00941-9

Abstract

Purpose: Acanthamoeba castellanii is an important opportunistic human protozoal pathogen that can cause both skin, ocular and brain infections. Recent studies have established that brews and solvent extract (SE) of green tea (Camellia sinensis) can inhibit the growth and encystation of A. castellanii. Here we characterized those growth and encystation inhibitions.

Methods: Herein, we characterize of the morphological and chemical changes that occur in the trophozoites and the encysting stage of A. castellanii after exposure to C. sinensis SE and brew using Transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) microspectroscopy and fluorescence-based assays.

Results: TEM showed ultrastructural changes in both A. castellanii stages. FTIR microspectroscopy revealed modifications of amide I and II band peaks in the C. sinensis-treated trophozoites, suggesting an inhibition of protein synthesis. Assessment of the nucleus integrity of trophozoites exposed to SE and brew revealed disruption of the nuclear membrane integrity, nuclear fragmentation, and chromatin degradation, and reduction in the quantity of DNA and RNA, indicating trophozoite death. These results are consistent with C. sinensis acting as a membrane-active anti-acanthamoebic, exhibiting amoebicidal activity against growing and encysting A. castellanii. This work underlines the importance of characterizing the effect of C. sinensis constituents, individually or in combinations, to clarify which ones are the primary components responsible for its action and the observed alterations in the structure and function of A. castellanii.

Conclusion: These results demonstrated that exposure to C. sinensis SE or brew alters the synthesis of protein, DNA, RNA and disrupts the cell wall integrity.

Item Type:	Journal article
Publication Title:	Acta Parasitologica
Creators:	Fakae, L.B., Zhong, J., Chan, K.L.A., Mekapothula, S., Cave, G.W.V., Zhu, X.-Q., Stevenson, C.W. and Elsheikha, H.M.
Publisher:	Springer Science and Business Media LLC
Date:	April 2025
Volume:	70
Number:	2
ISSN:	1230-2821
Identifiers:	Number Type 10.1007/s11686-024-00941-9 DOI 2395582 Other
Rights:	© The Author(s) 2025. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
Divisions:	Schools > School of Science and Technology
Record created by:	Laura Borcherds
Date Added:	07 Mar 2025 10:25
Last Modified:	07 Mar 2025 10:25
URI:	https://irep.ntu.ac.uk/id/eprint/53202