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Sauvey, C.

Publications and source records attributed to Sauvey, C..

3 recordsLinked to original sources

High-throughput phenotypic screen identifies a new family of potent anti-amoebic compounds

Entamoeba histolytica is a disease-causing parasitic amoeba which affects an estimated 50 million people worldwide, particularly in socioeconomically vulnerable populations experiencing water sanitation issues. Infection with E. histolytica is referred to as amoebiasis, and can cause symptoms such as colitis, dysentery, and even death in extreme cases. Drugs exist that are capable of killing this parasite, but they are hampered by downsides such as significant adverse effects at therapeutic concentrations, issues with patient compliance, the need for additional drugs to kill the transmissible cyst stage, and potential development of resistance. Past screens of small and medium sized chemical libraries have yielded anti-amoebic candidates, thus rendering high-throughput screening a promising direction for new drug discovery in this area. In this study, we screened a curated 80,000-compound library from Janssen pharmaceuticals against E. histolytica trophozoites in vitro, and from it identified a highly potent new inhibitor compound. Further experimentation confirmed the activity of this compound, as well as that of several structurally related compounds, originating from both the Janssen Jump-stARter library, and from chemical vendors, thus highlighting a new structure-activity relationship (SAR). In addition, we confirmed that the compound inhibited E. histolytica survival as rapidly as the current standard of care and inhibited transmissible cysts of the related model organism Entamoeba invadens. Together these results constitute the discovery of a novel class of chemicals with favorable in vitro pharmacological properties which may lead to an improved therapy against this parasite and in all of its life stages. Author summaryThe parasite Entamoeba histolytica represents a significant challenge in the field of global health. It currently infects and causes disease among millions of people worldwide, particularly those lacking access to clean water. Drugs exist to treat this disease, but nevertheless it persists as a problem, likely at least partly due to problems and downsides inherent to these drugs. Hence the search for new and better ones is needed. We report here our contribution to this search, consisting of testing a large, carefully-curated collection of tens of thousands of chemicals for their ability to kill E. histolytica. This large-scale test resulted in the identification of one of the compounds as potently anti-amoebic, capable of killing the parasite cells at extremely low concentrations. Further experimentation found several chemically-related compounds to also possess this property, and additionally found the first compound capable of killing the infective life stage of another Entamoeba parasite. These results have revealed an entire new family of chemicals with good potential for development as better drugs against this disease.

pharmacology and toxicology↗

Antineoplastic kinase inhibitors: a new class of potent anti-amoebic compounds

Entamoeba histolytica is a protozoan parasite which infects approximately 50 million people worldwide, resulting in an estimated 70,000 deaths every year. Since the 1960s E. histolytica infection has been successfully treated with metronidazole. However, drawbacks to metronidazole therapy exist, including adverse effects, a long treatment course, and the need for an additional drug to prevent cyst-mediated transmission. E. histolytica possesses a kinome with approximately 300 - 400 members, some of which have been previously studied as potential targets for the development of amoebicidal drug candidates. However, while these efforts have uncovered novel potent inhibitors of E. histolytica kinases, none have resulted in approved drugs. In this study we took the alternative approach of testing a set of twelve previously FDA-approved antineoplastic kinase inhibitors against E. histolytica trophozoites in vitro. This resulted in the identification of dasatinib, bosutinib, and ibrutinib as amoebicidal agents at low-micromolar concentrations. Next, we utilized a recently developed computational tool to identify twelve additional drugs with human protein target profiles similar to the three initial hits. Testing of these additional twelve drugs led to the identification of ponatinib, neratinib, and olmutinib were identified as highly potent, with EC50 values in the sub-micromolar range. All of these six drugs were found to kill E. histolytica trophozoites as rapidly as metronidazole. Furthermore, ibrutinib was found to kill the transmissible cyst stage of the model organism E. invadens. Ibrutinib thus possesses both amoebicidal and cysticidal properties, in contrast to all drugs used in the current therapeutic strategy. These findings together reveal antineoplastic kinase inhibitors as a highly promising class of potent drugs against this widespread and devastating disease. Author SummaryEvery year, nearly a hundred thousand people worldwide die from infection by the intestinal parasite Entamoeba histolytica, despite the widespread availability of metronidazole as a treatment. Here we report that six anticancer drugs of the kinase inhibitor class possess potent anti-amoebic properties, with one of them killing both actively dividing parasite and its transmissible cysts. These anticancer kinase inhibitors, including the dual-purpose drug with both amoebicidal and cysticidal activities may be used to treat amoebiasis, especially in cancer patients or in life-threatening brain- and liver-infecting forms of the disease.

microbiology↗

Antimalarial drug mefloquine kills both trophozoite and cyst stages of Entamoeba

Entamoeba histolytica is a protozoan parasite which infects approximately 50 million people worldwide, resulting in an estimated 70,000 deaths every year. Since the 1960s E. histolytica infection has been successfully treated with metronidazole. However, drawbacks to metronidazole therapy exist, including adverse effects, length of treatment, and the need for additional drugs to prevent transmission. All of these may decrease patient compliance and hence increase disease severity and spread of infection. In this study we identified the antimalarial drug mefloquine as possessing more potent, rapid, amoebicidal in vitro activity against E. histolytica trophozoites than metronidazole. We also showed that mefloquine could kill the cysts of a closely related reptilian parasite Entamoeba invadens unlike metronidazole. Additionally, mefloquine is known to possess a much longer half-life in human patients than metronidazole. This property, along with mefloquines rapid and broad action against E. histolytica position it as a promising new drug candidate against this widespread and devastating disease.\n\nAuthor SummaryEvery year, around 70,000 people worldwide die from infection by the intestinal parasite Entamoeba histolytica, despite the widespread availability of the drug metronidazole as a treatment. Part of the reason for this may be due to issues with patients failing to comply with the full course of treatment for the drug, due either to unpleasant side-effects, to the somewhat long treatment period, or the need for a secondary drug to kill the transmissible life stage of the parasite. In this report we discovered that the antimalarial drug mefloquine killed E. histolytica more potently and more rapidly than metronidazole, and, importantly, also killed the transmissible cyst stage of another Entamoeba species used as a model system. These findings make mefloquine an excellent candidate for an alternative drug to the current standard, with a simpler course of treatment and a more effective strategy to reduce the spread of this disease.

pharmacology and toxicology↗