Cellulose biosynthesis pathway is a potential target in the improved treatment of Acanthamoeba keratitis.

Abstract

Acanthamoeba is an opportunistic protozoan pathogen that can cause blinding keratitis as well as fatal granulomatous encephalitis. One of the distressing aspects in combating Acanthamoeba infections is the prolonged and problematic treatment. For example, current treatment against Acanthamoeba keratitis requires early diagnosis followed by hourly topical application of a mixture of drugs that can last up to a year. The aggressive and prolonged management is due to the ability of Acanthamoeba to rapidly adapt to harsh conditions and switch phenotypes into a resistant cyst form. One possibility of improving the treatment of Acanthamoeba infections is to inhibit the ability of these parasites to switch into the cyst form. The cyst wall is partially made of cellulose. Here, we tested whether a cellulose synthesis inhibitor, 2,6-dichlorobenzonitrile (DCB), can enhance the effects of the antiamoebic drug pentamidine isethionate (PMD). Our findings revealed that DCB can block Acanthamoeba encystment and may improve the antiamoebic effects of PMD. Using in vitro assays, the findings revealed that DCB enhanced the inhibitory effects of PMD on Acanthamoeba binding to and cytotoxicity of the host cells, suggesting the cellulose biosynthesis pathway as a novel target for the improved treatment of Acanthamoeba infections.

• Authors: Ricky Dudley, Selwa Alsam, Naveed Ahmed Khan
• Journal: Applied microbiology and biotechnology (Appl Microbiol Biotechnol) Vol. 75 Issue 1 Pg. 133-40 (May 2007) ISSN: 0175-7598 [Print] Germany
• PMID: 17225099 (Publication Type: Journal Article)

Chemical References

• Amebicides
• Nitriles
• Pentamidine
• Cellulose
• dichlobanil

Topics

• Acanthamoeba Keratitis (drug therapy, parasitology)
• Acanthamoeba castellanii (drug effects, growth & development, isolation & purification, metabolism)
• Amebicides (pharmacology, toxicity)
• Animals
• Brain (blood supply)
• Cells, Cultured
• Cellulose (antagonists & inhibitors, biosynthesis)
• Drug Synergism
• Endothelium, Vascular (cytology)
• Humans
• Microcirculation
• Nitriles (pharmacology, toxicity)
• Pentamidine (pharmacology, toxicity)