MMV020275 and MMV020490, promising compounds from malaria box for the treatment of equine piroplasmosis

2022 ◽  
pp. 101904
Author(s):  
Mohamed Abdo Rizk ◽  
Shimaa Abd El-Salam El-Sayed ◽  
Rasha Eltaysh ◽  
Ikuo Igarashi
2018 ◽  
Vol 184 (3) ◽  
pp. 95-95 ◽  
Author(s):  
Robert M Coultous ◽  
Paul Phipps ◽  
Charlie Dalley ◽  
Jane Lewis ◽  
Toni-Ann Hammond ◽  
...  

Equine piroplasmosis (EP) has historically been of minor concern to UK equine practitioners, primarily due to a lack of competent tick vectors. However, increased detection of EP tick vector species in the UK has been reported recently. EP screening is not currently required for equine importation, and when combined with recent relaxations in movement regulations, there is an increased risk regarding disease incursion and establishment into the UK. This study evaluated the prevalence of EP by both serology and PCR among 1242 UK equine samples submitted for EP screening between February and December 2016 to the Animal and Plant Health Agency and the Animal Health Trust. Where information was available, 81.5 per cent of submissions were for the purpose of UK export testing, and less than 0.1 per cent for UK importation. Serological prevalence of EP was 8.0 per cent, and parasite DNA was found in 0.8 per cent of samples. A subsequent analysis of PCR sensitivity in archived clinical samples indicated that the proportion of PCR-positive animals is likely to be considerably higher. The authors conclude that the current threat imposed by UK carrier horses is not adequately monitored and further measures are required to improve national biosecurity and prevent endemic disease.


F1000Research ◽  
2016 ◽  
Vol 5 ◽  
pp. 2701
Author(s):  
Gajinder Pal Singh

Background: New anti-malarial drugs are needed to meet the challenge of artemisinin resistance and to achieve malaria elimination and eradication. The new anti-malarial compounds are expected to have many desirable properties, such as activity against multiple stages of Plasmodium, low host cytotoxicity, and low propensity for resistance development, but whether and how these properties might be linked to each other is not clear. A better understanding of the relationship between activities of compounds against different stages of Plasmodium could help in the development of strategies to prioritize compounds with maximum potential for further development. Methods: We utilized the large amount of data that has recently been generated on 400 anti-malarial Malaria Box compounds and performed statistical analyses, such as rank correlation, hierarchical clustering, and principal-component analyses, to test associations between activities against different stages of Plasmodium, other pathogens, and human cells. Results: We found significant positive correlations between the activities of compounds against different stages of Plasmodium. Our results also show toxicity associated with assays conducted at higher compound concentrations. Principal-component analyses (PCA) of the data allowed differentiation of Plasmodium-specific activity from general toxicity and predicted success in in vitro evolution of resistance. We found that a single principal-component can capture most of the desirable properties of Malaria Box compounds and can be used to rank compounds from most desirable to least desirable activity-profile. Conclusions: Here, we provide a systematic strategy to prioritize Malaria Box compounds for further development. This approach may be applied for prioritization of anti-malarial compounds in general.


Author(s):  
Hayder Mohammad Al-Rammahi ◽  
Abdulameer Abed Hatem ◽  
Asaad Chasib Al-Atabi

This study was designed to detect equine piroplasmosis using the molecular technique in Al-Najaf province during the season that showed an increment in tick activities. Blood samples were collected from 110 horses with more than two signs of piroplasmosis. After DNA extraction, the product was examined by a polymerase chain reaction to amplify 18SrRNA. The results showed that the overall percentage of equine theileriosis was 38.18%. According to gender, the percentage of infection was 43.48% and 29.27% in females and males, respectively. Significant variations appeared between infected horses according to age, and the percentage of infection was 50% and 35.22% in less than 2 years and more than 2 years age, respectively. Moreover, the percentage of infection was 62.5% and 19.35% in animals with and without acariasis, respectively. Significant variations were also seen in equine theileriosis according to geographical areas, and the higher percentage was reported in Hera district (60.87%), while the lowest percentage was in the center of Al-Najaf (21.43%). This difference may be due to different distribution of vector of disease (tick), which may be the availability of the suitable weather that helped in the multiplication of the intermediate vectors. In conclusion, this study proved the variations in the occurrences of equine piroplasmosis according to gender, age, and geographical areas.


2018 ◽  
Vol 62 (4) ◽  
pp. e01505-17 ◽  
Author(s):  
R. S. Jumani ◽  
K. Bessoff ◽  
M. S. Love ◽  
P. Miller ◽  
E. E. Stebbins ◽  
...  

ABSTRACTCryptosporidiosis causes life-threatening diarrhea in children under the age of 5 years and prolonged diarrhea in immunodeficient people, especially AIDS patients. The standard of care, nitazoxanide, is modestly effective in children and ineffective in immunocompromised individuals. In addition to the need for new drugs, better knowledge of drug properties that drivein vivoefficacy is needed to facilitate drug development. We report the identification of a piperazine-based lead compound forCryptosporidiumdrug development, MMV665917, and a new pharmacodynamic method used for its characterization. The identification of MMV665917 from the Medicines for Malaria Venture Malaria Box was followed by dose-response studies,in vitrotoxicity studies, and structure-activity relationship studies using commercial analogues. The potency of this compound againstCryptosporidium parvumIowa and field isolates was comparable to that againstCryptosporidium hominis. Furthermore, unlike nitazoxanide, clofazimine, and paromomycin, MMV665917 appeared to be curative in a NOD SCID gamma mouse model of chronic cryptosporidiosis. MMV665917 was also efficacious in a gamma interferon knockout mouse model of acute cryptosporidiosis. To determine if efficacy in this mouse model of chronic infection might relate to whether compounds are parasiticidal or parasitistatic forC. parvum, we developed a novelin vitroparasite persistence assay. This assay suggested that MMV665917 was parasiticidal, unlike nitazoxanide, clofazimine, and paromomycin. The assay also enabled determination of the concentration of the compound required to maximize the rate of parasite elimination. This time-kill assay can be used to prioritize early-stageCryptosporidiumdrug leads and may aid in planningin vivoefficacy experiments. Collectively, these results identify MMV665917 as a promising lead and establish a new method for characterizing potential anticryptosporidial agents.


mSphere ◽  
2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Eric H. Jung ◽  
David J. Meyers ◽  
Jürgen Bosch ◽  
Arturo Casadevall

ABSTRACTSimilarities in fungal and animal cells make antifungal discovery efforts more difficult than those for other classes of antimicrobial drugs. Currently, there are only three major classes of antifungal drugs used for the treatment of systemic fungal diseases: polyenes, azoles, and echinocandins. Even in situations where the offending fungal organism is susceptible to the available drugs, treatment courses can be lengthy and unsatisfactory, since eradication of infection is often very difficult, especially in individuals with impaired immunity. Consequently, there is a need for new and more effective antifungal drugs. We have identified compounds with significant antifungal activity in the Malaria Box (Medicines for Malaria Ventures, Geneva, Switzerland) that have higher efficacy than some of the currently used antifungal drugs. Our best candidate, MMV665943 (IUPAC name 4-[6-[[2-(4-aminophenyl)-3H-benzimidazol-5-yl]methyl]-1H-benzimidazol-2-yl]aniline), here referred to as DM262, showed 16- to 32-fold-higher activity than fluconazole againstCryptococcus neoformans. There was also significant antifungal activity in other fungal species with known antifungal resistance, such asLomentospora prolificansandCryptococcus gattii. Antifungal activity was also observed against a common fungus,Candida albicans. These results are important because they offer a potentially new class of antifungal drugs and the repurposing of currently available therapeutics.IMPORTANCEMuch like the recent increase in drug-resistant bacteria, there is a rise in antifungal-resistant strains of pathogenic fungi. There is a need for novel and more potent antifungal therapeutics. Consequently, we investigated a mixed library of drug-like and probe-like compounds with activity inPlasmodiumspp. for activity against two common fungal pathogens,Cryptococcus neoformansandCandida albicans, along with two less common pathogenic species,Lomentospora prolificansandCryptococcus gattii. We uncover a previously uncharacterized drug with higher broad-spectrum antifungal activity than some current treatments. Our findings may eventually lead to a compound added to the arsenal of antifungal therapeutics.


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