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Neosporosis is an infectious disease caused by Neospora caninum , and it primarily affects cattle and dogs. An infection by N. caninum causes fetal abortion and neonatal mortality. Previous proteomics and immunoscreening analyses revealed that N. caninum dense granule antigen 2 (NcGRA2) has potential for serodiagnosis of N. caninum. Consequently, we expressed the truncated NcGRA2 (NcGRA2t), which lacks a signal peptide. We compared the serodiagnostic performances of recombinant NcGRA2t with that of truncated surface antigen 1 of N. caninum (NcSAG1t). Specificity testing using sera from mice infected with Toxoplasma gondii indicated that the NcGRA2t recombinant protein does not cross-react with T. gondii . In addition, we detected anti-NcGRA2t antibody at the acute stage in experimentally infected dogs, while detecting anti-NcSAG1t antibody during both the acute and chronic stages. Our results suggest that the levels of anti-NcGRA2 antibody reflect parasite activation in dogs. In conclusion, antibodies against NcGRA2t and NcSAG1t are suitable indicators to distinguish the acute and chronic stages of N. caninum infection. [ABSTRACT FROM AUTHOR]

Abstract: Toxoplasma gondii is the etiologic agent of toxoplasmosis. Although the combination of sulfadiazine and pyrimethamine is used as therapy for this disease, these drugs can have serious side effects and its use is limited in pregnancy. Therefore there is a need for new anti-T. gondii drugs in the clinic. Some systems for T. gondii drug screening have been described, but these have limitations and can be difficult. In order to solve these problems, we established a system to screen drugs in vitro that involved using cell viability methods to calculate drug selectivities, which are Trypan blue, [3-(4,5-dimethylthiazol-zyl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazoliuzolium, inner salt] (MTS) method and lactate dehydrogenase (LDH) assay. These assays were simple to establish and perform. The IC50 values calculated from the morphological assay were not significantly different from the EC50 values calculated using the other three methods. In particular, the results of the morphological assay showed a distinct association with the MTS assay (R =0.9841). These assays could be used for a wide range of applications in the screening of new drugs and may provide an alternative to the techniques currently used to screen for candidate anti-T. gondii compounds in vitro. In this study, we also tested many compounds and identified some that had a good anti-T. gondii effect in vitro based on the MTS assay. This simple and fast system allowed us to determine which compounds to investigate further using in vivo experiments. [Copyright &y& Elsevier]

• Four series of DHA derivatives were evaluated for anti- T. gondii activity in vitro. • Compound A2 had the better anti- T. gondii activity than DHA in in vitro and in vivo. • Compound A2 had better inhibitory effects on T. gondii in vivo than spiramycin. In this study, four series of dihydroartemisinin derivatives were designed, synthesized, and evaluated for anti-toxoplasma gondii activity, and calculated the selectivity index (SI). It was the higher the SI, the better the effect of this compound against Toxoplasma gondii. Our goal was to filter out compounds that were bigger SI than the lead compound. The compound with the highest SI was selected for the anti-toxoplasmosis test in mice in vivo. Among the synthesized compounds, the (3R,5aS,6R,8aS,9R,12R,12aR)-3,6,9-trimethyl-decahydro-12 H -3,12-epoxy[1,2]di-oxepino[4,3 - i ]isochromen-10-yl-(te-rt- butoxycarbonyl)- l -alaninate (A2) exhibited the most potent anti- T. gondii activity and low cytotoxicity (SI: 6.44), yielding better results than the lead compound DHA (SI: 1.00) and the clinically used positive-control drug spiramycin (SI: 0.72) in vitro. Furthermore, compound A2 had better growth inhibitory effects on T. gondii in vivo than spiramycin did and significantly reduced the number of tachyzoites in the peritoneal cavity of mice (P < 0.01). The evaluation of the data generated in the T. gondii mouse infection model indicates that compound A2 treatment was a good inhibitor of T. gondii in vivo and that it was effective in relieving the liver damage induced by T. gondii. In addition, the results of a docking study revealed that A2 could become a better T. gondii calcium-dependent protein kinase1 (Tg CDPK1) inhibitor. For this reason, compound A2 has potential as an anti-parasitic drug. Further studies are required to elucidate the mechanism of the action of compound A2, as well as to develop drug delivery systems for patients. [ABSTRACT FROM AUTHOR]

Variants of the cytoplasmic FMR1-interacting protein 2 (CYFIP2) gene are associated with early-onset epileptic encephalopathy, intellectual disability, and developmental delay. However, the current understanding of the molecular functions of CYFIP2 is limited to those related to actin dynamics, and thus, the detailed mechanisms of CYFIP2 -associated brain disorders remain largely unknown. Here, we isolated the neonatal forebrain CYFIP2 complex using newly generated Cyfip2-3×Flag knock-in mice, and performed mass spectrometry-based analyses to identify proteins in the complex. The CYFIP2 interactome, consisting of 140 proteins, contained not only the expected actin regulators but also 25 RNA-binding proteins (RBPs) including Argonaute proteins. Functionally, overexpression of brain disorder-associated CYFIP2 R87 variants, but not wild-type, inhibited stress granule formation in HeLa cells. Mechanistically, the CYFIP2 R87 variants formed intracellular clusters with Argonaute proteins under both basal and stress conditions, and thereby possibly preventing their assembly into stress granules. Beyond identifying CYFIP2 interactors in vivo , these results may provide novel insights for better understanding the molecular mechanisms of CYFIP2 -associated brain disorders. • The forebrain CYFIP2 complex was isolated from neonatal Cyfip2-3×Flag KI mice. • Mass spectrometry-based analyses identified 140 proteins in the CYFIP2 complex. • The complex included actin regulators and RNA-binding proteins such as Argonaute. • Disease-associated CYFIP2 R87 variants inhibited stress granule formation in cells. • The CYFIP2 R87 variants formed intracellular clusters with Argonaute. [ABSTRACT FROM AUTHOR]

Variants of the SHANK3 gene, which encodes a core scaffold protein of the postsynaptic density of excitatory synapses, have been causally associated with numerous brain disorders. Shank3 proteins directly bind zinc ions through their C-terminal sterile α motif domain, which enhances the multimerization and synaptic localization of Shank3, to regulate excitatory synaptic strength. However, no studies have explored whether zinc affects the protein interactions of Shank3, which might contribute to the synaptic changes observed after zinc application. To examine this, we first purified Shank3 protein complexes from mouse brain synaptosomal lysates that were incubated with different concentrations of ZnCl 2 , and analyzed them with mass spectrometry. We used strict criteria to identify 71 proteins that specifically interacted with Shank3 when extra ZnCl 2 was added to the lysate. To characterize the zinc-induced Shank3 interactome, we performed various bioinformatic analyses that revealed significant associations of the interactome with subcellular compartments, including mitochondria, and brain disorders, such as bipolar disorder and schizophrenia. Together, our results showing that zinc affected the Shank3 protein interactions of in vitro mouse synaptosomes provided an additional link between zinc and core synaptic proteins that have been implicated in multiple brain disorders. [ABSTRACT FROM AUTHOR]

Botanical medicinal plants have aroused our interest to deal with Toxoplasmosis which can causes serious public health problems. Nipagic acid, gallic acid, ethyl gallate, phloretic acid, protocatechuic acid, methyl p -coumarate, arbutin, and homoprotocatechuic acid are first isolated from Orostachys malacophylla (Pallas) Fischer, their inhibition rate, survival rate, biochemical and viscera index are evaluated using gastric epithelia strain-1(GES-1). Among them, arbutin can effectively prolong the survival time of mice acutely infected with T. gondii , and exhibit the same curative effect as Spiramycin (Spi) group in terms of the glutathione (GSH) and malondialdehyde (MDA) content, alleviate hepatomegaly and splenomegaly. Structure-activity relationship (SAR) and molecular docking implies that phenolic hydroxyl group would be preferred for improvement of activity. In a summary, arbutin is a potential anti- T. gondii candidate for clinical application. [Display omitted] • Phenolic compounds isolated from O. malacophylla were first evaluated for anti- T. gondii activity in vitro, in vivo. • The inhibition rate, the survival rate, selectivity index of arbutin better than the positive control Spiramycin. • Structure-activity relationship implies that phenolic hydroxyl group would be preferred for improvement of activity. • Arbutin is effective in relieving the liver damage induced by T. gondii. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii ( T . gondii ) is an important pathogen which can causes serious public health problems. Since the current therapeutic drugs for toxoplasmosis present serious host toxicity, research on effective and new substances of relatively low toxicity is urgently needed. This study was carried out to evaluate the anti-parasitic effect of oxymatrine (OM) and matrine (ME) against T . gondii in vitro and in vivo . In our study, the anti- T . gondii activities of ME and OM were evaluated in vitro using cell counting kit-8 assay, morphological observation and trypan blue exclusion assay. In vivo , mice were sacrificed four days post-infection and ascites were drawn out to determine the extent of tachyzoite proliferation. Viscera indexes and liver biochemical parameters, such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), glutathione (GSH) and malondialdehyde (MDA), were examined to evaluate the toxicity of compounds to mice. As a result, OM and ME showed anti- T . gondii activity but low selectivity toxicity to HeLa cells. Both compounds also significantly decreased the number of tachyzoites in peritoneal cavity and recovered the levels of ALT, AST, GSH and MDA in liver. Moreover, the mice treated with OM or ME achieved better results in viscera index and survival rate than that of spiramycin. These results suggest that OM and ME are likely the sources of new drugs for toxoplasmosis, and further studies will be necessary to compare the efficacy of drug combination, as well as identify its action of mechanism. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii is an important pathogen that causes serious public health problems. Currently, therapeutic drugs for toxoplasmosis cause serious side effects, and more effective and novel substances with relatively low toxicity are urgently needed. Ursolic acid (UA) has many properties that can be beneficial to healthcare. In this study, we synthesized eight series of UA derivatives bearing a tetrazole moiety and evaluated their anti- T. gondii activity in vitro using spiramycin as a positive control. Most of the synthesized derivatives exhibited better anti- T. gondii activity in vitro than UA , among which compound 12a exhibited the most potent anti- T. gondii activity. Furthermore, the results of biochemical parameter determination indicated that 12a effectively restored the normal body weight of mice infected with T. gondii , reduced hepatotoxicity, and exerted significant anti-oxidative effects compared with the findings for spiramycin. Additionally, our molecular docking study indicated that the synthesized compounds could act as potential inhibitors of T. gondii calcium-dependent protein kinase 1 (TgCDPK1), with 12a possessing strong affinity for TgCDPK1 via binding to the key amino acids GLU129 and TYR131. Image 1 • The synthesized ursolic acid derivatives bearing tetrazole moieties were evaluated for their anti- T. gondii activities. • Compound 12a is a promising hit for the development of new anti- T. gondii agents. • The investigation of the mechanism in vivo and binding mode of action of 12a to TgCDPK1 was performed. [ABSTRACT FROM AUTHOR]