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Introduction

Tanacetum vulgare (TV) and other Asteraceae species are ethno-veterinary herbs with known anthelminthic (AH) potential. The present study aims to investigate the in vitro AH effect of TV and the alpine Cicerbita alpina (CA). Methanolic extracts (ME) of the dried areal plant parts were prepared submitted to a bioactivity guided fractionation workflow employing Ascaridia galli eggs in an embryonic development (ED) assay.

Methods

Eggs were isolated from the A. galli uterus and exposed in vitro to the extracts, their fractions, positive (flubendazole) and negative controls. The ability of the test samples to affect the ED of A. galli was assessed in duplicate at a concentration of 0.5mg/ml. ED was evaluated weekly from the day of egg isolation to day 28. Analysis was performed using a generalized linear mixed model, stating a negative binomial distribution. Test samples, concentrations and week were set as fixed effects.

Results

ME of CA showed significantly lower (P < 0.05) ED (35%) compared to TV (42%) and the untreated control. Phenolic acids is believed to be a class of active constituents within Asteraceae responsible for their AH effect. Thus, the phenolic content of the ME was investigated via the Folin-Ciocalteu method and determined to be 7.4 and 5.9% for CA and TV, respectively. The investigation of the fractions revealed the butanol sample of CA as most promising. HPLC-DAD-MS analysis was performed to annotate the potentially active phenolic acids, suggesting the presence of caffeic acid derivatives in high abundance.

Conclusions

The obtained CA samples showed promising AH potential. To find alternative A. galli deworming strategies, this plant species should be further investigated.

Project funded by EUREGIO (Interregional Project Networks) (IPN 119) ‘HERBAL’.

Introduction

Neospora caninum is an apicomplexan parasite closely related to Toxoplasma gondii and causes abortion, stillbirth and/or fetal malformation in livestock. Target-based drug development has led to the synthesis of calcium-dependent protein kinase 1 inhibitors named bumped kinase inhibitors (BKIs). Several BKIs have excellent efficacy against neosporosis in vitro and in vivo. However, several BKIs impair fertility in pregnant mouse models and cause embryonic malformation in a zebrafish (Danio rerio) model. Similar to the first-generation antiprotozoal drug quinine, some BKIs have a quinoline core structure.

Methods

To identify common targets in both organisms, we performed differential affinity chromatography with cell-free extracts from N. caninum tachyzoites and D. rerio embryos using the 5-aminopyrazole-4-carboxamide compound BKI-1748 and quinine columns coupled to epoxy-activated sepharose followed by mass spectrometry. BKI-binding proteins of interest were identified in eluates from columns coupled to BKI-1748, or in eluates from BKI-1748 as well as quinine columns.

Results

In N. caninum, 12 proteins were bound specifically to BKI-1748, and 105 proteins, including NcCDPK1, were bound to both BKI-1748 and quinine. For D. rerio, the corresponding numbers were 13 and 98 binding proteins, respectively. In both, a majority of BKI-1748 binding proteins was involved in RNA binding and modification, in particular splicing. Also both datasets contained proteins involved in DNA binding or modification and key steps of intermediate metabolism.

Conclusions

These results suggest that BKI-1748 interacts with not only specific targets in apicomplexans such as CDPK1, but also with targets in other eukaryotes, which are involved in common essential pathways.

Introduction

Psoroptic mange, caused by infestation with the ectoparasitic mite, Psoroptes ovis, is highly contagious, resulting in intense pruritus and represents a major welfare and economic concern. Control relies on injectable endectocides and organophosphate dips, but concerns over residues, environmental contamination, and the development of resistance threaten their sustainability, highlighting interest in alternative control methods. However, development of vaccines and identification of chemotherapeutic targets is hampered by the lack of P. ovis transcriptomic and genomic resources.

Methods

Here we applied next generation sequencing methods to generate a transcriptomic atlas of gene expression in P. ovis across multiple life cycle stages, including larvae, protonymphs, tritonymphs, adult males and adult females.

Results

Gene expression analysis revealed feeding- and stage-specific patterns of gene expression and network-based clustering revealed 14 gene clusters demonstrating either single- or multi-stage specific gene expression patterns, with 3075 female-specific, 890 male-specific and 112, 217 and 526 transcripts showing larval, protonymph and tritonymph specific-expression, respectively. Pair-wise analysis of gene expression between life-cycle stages revealed patterns of sex-biased expression and identified novel P. ovis multigene families including known allergens.

Conclusions

The first genomic and transcriptomic atlas of gene expression in P. ovis represents a unique resource for this economically important parasite and also provides the first gene expression atlas for an astigmatid parasitic mite, which can now be exploited by the wider acarid-research community.

Introduction

Beekeeping is the set of techniques related to the handling, breeding, and products of bees (production of queen bees) and by-products such as honey, royal jelly, propolis, wax, and pollen. Mexico has a beekeeping inventory of more than 1.9 million hives, its honey production is more than 70 thousand tons/year. Aggravating elements that contribute to the destruction of hives are the use of pesticides, monocultures, and parasitic diseases of bees, such as varroasis, acarapisosis, and nosemosis.

Methods

Specimens were collected from Ciudad Juárez, Hidalgo del Parral, Ignacio Allende Valley, Jiménez, Casas Grandes, Chihuahua, Delicias, Aldama, and Meoqui, all cities in the state of Chihuahua, Mexico. In each of the sites, specimens from beekeeping centers and wild bees were collected, obtaining a total of 39 samples of 60 bees. For the detection of Varroa sp. and Nosema sp., specifications and techniques used are established in Mexican Official Standard NOM-056-ZOO-1995, while for the detection of Acarapis woodi, it was by direct preparation.

Results

From the samples analyzed (39), Nosema sp. was observed in 100% presenting a very slight severity (0.01 to 1.0 million spores per bee). For Varroa sp., 100% of the analyzed apiaries were positive in different degrees of infestation; however, in the samples of wild bees, they were not found, except in the city of Jiménez. There was no detection of Acarapis woodi in any of the samples analyzed.

Conclusions

Nosemosis is a disease that occurs in adult bees, affecting the intestine-ventricle of bees weakening their organism. Varroa mites penetrate between the abdominal plates of the bees to suck the hemolymph, presenting damage and shortening their life, changing their behavior, and increased susceptibility to diseases.

Introduction

The vectorial capability of Hyalomma lusitanicum to transmit Coxiella burnetii has been recently demonstrated both in field and artificial feeding systems. Also it is known the high prevalence of C. burnetii in ticks. The aim of this work was to study the seasonal dynamic of C. burnetii infections in wild rabbits and its relation with H. lusitanicum under field conditions.

Methods

The presence of C. burnetii was studied both in rabbits and in a subsample of ticks obtained from two wild rabbit populations that differ in the high or very low prevalence of H. lusitanicum. ELISA in rabbit’s sera and RT-PCR in rabbits and ticks were performed.

Results

The pattern of DNA was similar in these two populations but pattern of antibodies varied from August onwards decreasing in low infestated rabbits (coinciding with the decline in DNA) while it remained at high levels in those with high H. lusitanicum prevalence.

Conclusions

Similar patterns of DNA and antibodies were detected in both populations over the half of the year. However, after summer, the antibodies level was only maintained in rabbits highly infested with H. lusitanicum. This result suggests that the presence of infected H. lusitanicum ticks is sufficient to contribute to the stimulation of antibody production in wild rabbits.

Introduction

The rational approach towards finding effective anti-tick preparations and/or vaccines has been traditionally focused on the tick-specific adaptation to their parasitic lifestyle and major physiological departures from their hosts. We have been long searching for vulnerable molecular targets associated with physiological processes such as blood digestion or heme/iron metabolism. However, targeting the key molecules involved in these processes by RNAi-KD or by experimental vaccination only rarely resulted in a clear impairment of tick development or reproduction. On the other hand, several recent examples have demonstrated that targeting almost canonical processes between parasites and their hosts might surprisingly lead to the discovery of potent antiparasitic compounds. This is conditioned by the width of the therapeutic window between the toxicity to the parasite and host.

Methods

Inspired by these results and using our model tick Ixodes ricinus, we have begun to investigate the potential of targeting quite conserved physiological processes and metabolic pathways using RNAi silencing or chemical inhibition via artificial tick feeding.

Results

We examined the potential of targeting tick tyrosine degradation pathway, synthesis of selected amino-acid tRNA synthetases, components of the insulin signaling pathway, proteasome, glutamate-gated chloride channels, or cholesterol and lipid uptake. Several quite striking phenotypes on tick development or mortality were achieved.

Conclusions

These results warrant further research activities in our endeavor towards finding novel potential targets for anti-tick preparations or vaccines.

Acknowledgment: GACR No. 21-08826S and ERD Funds (No.CZ.02.1.01/0.0/0.0/16_019/0000759)