Heloisa F. Frota, Pedro F. Barbosa, Carolline M. A. Lorentino, Lorena R. F. Affonso, Lívia S. Ramos, Simone S. C. Oliveira, Lucieri O. P. Souza, Olufunso O. Abosede, Adeniyi S. Ogunlaja, Marta H. Branquinha, André L. S. Santos
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引用次数: 0
Abstract
Candida species undeniably rank as the most prevalent opportunistic human fungal pathogens worldwide, with Candida albicans as the predominant representative. However, the emergence of non-albicans Candida species (NACs) has marked a significant shift, accompanied by rising incidence rates and concerning trends of antifungal resistance. The search for new strategies to combat antifungal-resistant Candida strains is of paramount importance. Recently, our research group reported the anti-Candida activity of a coordination compound containing copper(II) complexed with theophylline (theo) and 1,10-phenanthroline (phen), known as “CTP” – Cu(theo)2phen(H2O).5H2O. In the present work, we investigated the mechanisms of action of CTP against six medically relevant, antifungal-resistant NACs, including C. auris, C. glabrata, C. haemulonii, C. krusei, C. parapsilosis and C. tropicalis. CTP demonstrated significant efficacy in inhibiting mitochondrial dehydrogenases, leading to heightened intracellular reactive oxygen species production. CTP treatment resulted in substantial damage to the plasma membrane, as evidenced by the passive incorporation of propidium iodide, and induced DNA fragmentation as revealed by the TUNEL assay. Scanning electron microscopy images of post-CTP treatment NACs further illustrated profound alterations in the fungal surface morphology, including invaginations, cavitations and lysis. These surface modifications significantly impacted the ability of Candida cells to adhere to a polystyrene surface and to form robust biofilm structures. Moreover, CTP was effective in disassembling mature biofilms formed by these NACs. In conclusion, CTP represents a promising avenue for the development of novel antifungals with innovative mechanisms of action against clinically relevant NACs that are resistant to antifungals commonly used in clinical settings.
期刊介绍:
BioMetals is the only established journal to feature the important role of metal ions in chemistry, biology, biochemistry, environmental science, and medicine. BioMetals is an international, multidisciplinary journal singularly devoted to the rapid publication of the fundamental advances of both basic and applied research in this field. BioMetals offers a forum for innovative research and clinical results on the structure and function of:
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BioMetals is a journal for metals researchers who practice in medicine, biochemistry, pharmacology, toxicology, microbiology, cell biology, chemistry, and plant physiology who are based academic, industrial and government laboratories.