Selective targeting of phosphodiesterases to develop potent antiparasitic drugs.

Regulation of intracellular cyclic nucleotides to avoid homeostatic imbalances is achieved through catabolic activity of phosphodiesterases (PDEs). Recently, Ajiboye et al. reported validation of Cryptosporidium PDE1 (CpPDE1) as a viable drug target and identified optimized pyrazolopyrimidines with selective activity against CpPDE1 over human PDEs and with potent anticryptosporidial efficacy.

Signal recognition particle RNA is critical for genetic competence and virulence of .

Unlabelled: (pneumococcus) causes a wide range of important human infectious diseases, including pneumonia, pneumonia-derived sepsis, otitis media, and meningitis. Pneumococcus produces numerous secreted proteins that are critical for normal physiology and pathogenesis. The membrane targeting and translocation of these secreted proteins are partly mediated by the signal recognition particle (SRP) complex, which consists of 4.

Mendelian segregation and high recombination rates facilitate genetic analyses in Cryptosporidium parvum.

Very little is known about the process of meiosis in the apicomplexan parasite Cryptosporidium despite the essentiality of sex in its life cycle. Most cell lines only support asexual growth of Cryptosporidium parvum (C. parvum), but stem cell derived intestinal epithelial cells grown under air-liquid interface (ALI) conditions support the sexual cycle.

Mendelian segregation and high recombination rates facilitate genetic analyses in .

Very little is known about the process of meiosis in the apicomplexan parasite despite the essentiality of sex in its life cycle. Most cell lines only support asexual growth of (), but stem cell derived intestinal epithelial cells grown under air-liquid interface (ALI) conditions support the sexual cycle. To examine chromosomal dynamics during meiosis in , we generated two transgenic lines of parasites that were fluorescently tagged with mCherry or GFP on chromosomes 1 or 5, respectively.

infection of human small intestinal epithelial cells induces type III interferon and impairs infectivity of Rotavirus.

Cryptosporidiosis is a major cause of severe diarrheal disease in infants from resource poor settings. The majority of infections are caused by the human-specific pathogen and absence of in vitro growth platforms has limited our understanding of host-pathogen interactions and development of effective treatments. To address this problem, we developed a stem cell-derived culture system for using human enterocytes differentiated under air-liquid interface (ALI) conditions.

infection of human small intestinal epithelial cells induces type III interferon and impairs infectivity of Rotavirus.

Cryptosporidiosis is a major cause of severe diarrheal disease in infants from resource poor settings. The majority of infections are caused by the human-specific pathogen and absence of in vitro growth platforms has limited our understanding of host-pathogen interactions and development of effective treatments. To address this problem, we developed a stem cell-derived culture system for using human enterocytes differentiated under air-liquid interface (ALI) conditions.

Combination of inhibitors for two glycolytic enzymes portrays high synergistic efficacy against .

is an intracellular protozoan parasite that causes serious enteric disease in humans and in a wide range of animals worldwide. Despite its high prevalence, no effective therapeutic drugs are available against life-threatening cryptosporidiosis in at-risk populations including malnourished children, immunocompromised patients, and neonatal calves. Thus, new efficacious drugs are urgently needed to treat all susceptible populations with cryptosporidiosis.

Multiple pathways for glucose phosphate transport and utilization support growth of .

is an obligate intracellular parasite with a highly reduced mitochondrion that lacks the TCA cycle and the ability to generate ATP, making the parasite reliant on glycolysis. Genetic ablation experiments demonstrated that neither of the two putative glucose transporters CpGT1 and CpGT2 were essential for growth. Surprisingly, hexokinase was also dispensable for parasite growth while the downstream enzyme aldolase was required, suggesting the parasite has an alternative way of obtaining phosphorylated hexose.

Broad-Spectrum Inhibitors for Conserved Unique Phosphoethanolamine Methyltransferases in Parasitic Nematodes Possess Anthelmintic Efficacy.

In humans, nematode infections are prevalent in developing countries, causing long-term ill health, particularly in children. Worldwide, nematode infections are prevalent in livestock and pets, affecting productivity and health. Anthelmintic drugs are the primary means of controlling nematodes, but there is now high prevalence of anthelmintic resistance, requiring urgent identification of new molecular targets for anthelmintics with novel mechanisms of action.

Past, current, and potential treatments for cryptosporidiosis in humans and farm animals: A comprehensive review.

The intracellular protozoan parasite of the genus is among the leading causes of waterborne diarrheal disease outbreaks throughout the world. The parasite is transmitted by ingestion of infective oocysts that are highly stable in the environment and resistant to almost all conventional disinfection methods and water treatments. Control of the parasite infection is exceedingly difficult due to the excretion of large numbers of oocysts in the feces of infected individuals that contaminate the environment and serve as a source of infection for susceptible hosts including humans and animals.

MSP-1 capture antigen-based ELISA for detection of avian malaria antibodies in African penguins ().

Avian malaria, caused by spp. and transmitted by mosquitos, is a leading cause of mortality of captive penguins. Antimalarial drugs are currently used to control infections in penguins.

Activity of (1-benzyl-4-triazolyl)-indole-2-carboxamides against Toxoplasma gondii and Cryptosporidium parvum.

Parasitic diseases such as toxoplasmosis and cryptosporidiosis remain serious global health challenges, not only to humans but also to domestic animals and wildlife. With only limited treatment options available, Toxoplasma gondii and Cryptosporidium parvum (the causative agents of toxoplasmosis and cryptosporidiosis, respectively) constitute a substantial health threat especially to young children and immunocompromised individuals. Herein, we report the synthesis and biological evaluation of a series of novel (1-benzyl-4-triazolyl)-indole-2-carboxamides and related compounds that show efficacy against T.

Pyruvate Kinase Inhibitors With Anti-cryptosporidial Efficacy.

is a highly prevalent protozoan parasite that causes a diarrheal disease in humans and animals worldwide. Thus far, the moderately effective nitazoxanide is the only drug approved by the United States Food and Drug Administration for treating cryptosporidiosis in immunocompetent humans. However, no effective drug exists for the severe disease seen in young children, immunocompromised individuals and neonatal livestock.

Anti-protozoal activity of Thymol and a Thymol ester against Cryptosporidium parvum in cell culture.

Cryptosporidium parvum is a protozoan parasite that infects intestinal epithelial cells causing malabsorption and severe diarrhea. The monoterpene thymol has been reported to have antifungal and antibacterial properties but less is known about the antiparasitic effect of this compound. Terpenes are sometimes unsuitable for therapeutic and food applications because of their instability.

Novel acyl carbamates and acyl / diacyl ureas show in vitro efficacy against Toxoplasma gondii and Cryptosporidium parvum.

Toxoplasma gondii and Cryptosporidium parvum are protozoan parasites that are highly prevalent and opportunistically infect humans worldwide, but for which completely effective and safe medications are lacking. Herein, we synthesized a series of novel small molecules bearing the diacyl urea scaffold and related structures, and screened them for in vitro cytotoxicity and antiparasitic activity against T. gondii and C.

Interaction of apigenin-7-O-glucoside with pyrimethamine against growth.

Apigenin-7-O-glucoside, a flavonoid glucoside known to inhibit cancer cell growth, fungi growth, both intra and extracellular reactive oxygen species generation, causing cell arrest and damage to the plasma membrane, was tested alone or in combination with a dihydrofolate inhibitor (pyrimethamine) against () growth. The anti- activity was carried out using a high throughput antiparasitic drug screening cell-based assay known as 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H tetrazolium, monosodium salt (WST-8) and fluorescence plate reader. The 50% effective concentration inhibition and 95% confidence interval values for individual and combination treatments against were 0.

In Vitro Culture of Cryptosporidium parvum Using Stem Cell-Derived Intestinal Epithelial Monolayers.

Cryptosporidium parvum has a complex life cycle consisting of asexual and sexual phases that culminate in oocyst formation in vivo. The most widely used cell culture platforms to study C. parvum only support a few days of growth and do not allow the parasite to proceed past the sexual stages to complete oocyst formation.

Novel lactate dehydrogenase inhibitors with in vivo efficacy against Cryptosporidium parvum.

Cryptosporidium parvum is a highly prevalent zoonotic and anthroponotic protozoan parasite that causes a diarrheal syndrome in children and neonatal livestock, culminating in growth retardation and mortalities. Despite the high prevalence of C. parvum, there are no fully effective and safe drugs for treating infections, and there is no vaccine.

Morpholino-mediated in vivo silencing of Cryptosporidium parvum lactate dehydrogenase decreases oocyst shedding and infectivity.

Cryptosporidium is a highly prevalent protozoan parasite that is the second leading cause of childhood morbidity and mortality due to diarrhoea in developing countries, and causes a serious diarrheal syndrome in calves, lambs and goat kids worldwide. Development of fully effective drugs against Cryptosporidium has mainly been hindered by the lack of genetic tools for functional characterization and validation of potential molecular drug targets in the parasite. Herein, we report the development of a morpholino-based in vivo approach for Cryptosporidium parvum gene knockdown to facilitate determination of the physiological roles of the parasite's genes in a murine model.

Small GTPase Immunity-Associated Proteins Mediate Resistance to Toxoplasma gondii Infection in Lewis Rat.

Rats vary in their susceptibilities to infection depending on the rat strain. Compared to the -susceptible Brown Norway (BN) rat, the Lewis (LEW) rat is extremely resistant to Thus, these two rat strains are ideal models for elucidating host mechanisms that are important for host resistance to infection. Therefore, in our efforts to unravel molecular factors directing the protective early innate immune response in the LEW rat, we performed RNA sequencing analysis of the LEW versus BN rat with or without infection.