Novel tick glutathione transferase inhibitors as promising acaricidal compounds

Insight Into the Dynamics of the Ixodes ricinus Nymphal Midgut Proteome

Ticks are ectoparasites that feed on blood and have an impressive ability to consume and process enormous amounts of host blood, allowing extremely long periods of starvation between blood meals. The central role in the parasitic lifestyle of ticks is played by the midgut. This organ efficiently stores and digests ingested blood and serves as the primary interface for the transmission of tick-borne pathogens. In this study, we used a label-free quantitative approach to perform a novel dynamic proteomic analysis of the midgut of Ixodesricinus nymphs, covering their development from unfed to pre-molt stages. We identified 1534 I. ricinus-specific proteins with a relatively low proportion of host proteins. This proteome dataset, which was carefully examined by manual scrutiny, allowed precise annotation of proteins important for blood meal processing and their dynamic changes during nymphal ontogeny. We focused on midgut molecules related to lipid hydrolysis, storage, and transport, opening a yet unexplored avenue for studying lipid metabolism in ticks. Further dynamic profiling of the tick's multi-enzyme digestive network, protease inhibitors, enzymes involved in redox homeostasis and detoxification, antimicrobial peptides, and proteins responsible for midgut colonization by Borrelia spirochetes promises to uncover new targets for targeting tick nymphs, the most critical life stage for transmission the pathogens that cause tick-borne diseases.

Babesiosis concurrent with multiple abscesses from Staphylococcus aureus infection: A case report

Background

Babesiosis is a tick-borne illness. These patients may have signs of a systemic inflammatory response, but abscess formation is unusual. Multiple abscesses in a patient with confirmed babesiosis is very rare, so concurrent infection by another pathogen should be considered.

Case presentation

We report a 42-year-old male patient who had fever, chills, joint pain, abdominal pain, and altered mental status after a possible tick bite on his right foot while fishing in a river. The laboratory tests, including a blood smear, suggested babesiosis. Imaging studies showed multiple brain and spleen abscesses due to Staphylococcus aureus based on the results of a blood culture and next-generation sequencing. The patient eventually recovered after treatment with azithromycin, fosfomycin, and vancomycin.

Conclusion

Concurrent bacterial infection can occur in a patient with babesiosis. Additional tests should be performed when a babesiosis patient presents with signs inconsistent with Babesia infection. Prompt and appropriate treatment is necessary and may be life-saving for these patients.

Putative target sites in synganglion for novel ixodid tick control strategies

Acaricide resistance is a global problem that has impacts worldwide. Tick populations with broad resistance to all commercially available acaricides have been reported. Since resistance selection in ticks and their role in pathogen transmission to animals and humans result in important economic and public health burden, it is essential to develop new strategies for their control (i.e., novel chemical compounds, vaccines, biological control). The synganglion is the tick central nervous system and it is responsible for synthesizing and releasing signaling molecules with different physiological functions. Synganglion proteins are the targets of the majority of available acaricides. In this review we provide an overview of the mode-of-action and resistance mechanisms against neurotoxic acaricides in ticks, as well as putative target sites in synganglion, as a supporting tool to identify new target proteins and to develop new strategies for tick control.

Evaluation of Tick Abundance and Pyrethroid Resistance Via Determination of Glutathione-S-Transferases Activity

Controlling the number of ticks as carriers of infectious diseases is very important. The process is sometimes compromised by activating the protective mechanisms of the tick itself. Glutathione-S-transferases activity (GSTs) was the subject of our investigation of tick abundance after pyrethroid treatment. We determined GSTs activity in ticks collected from six locations in Belgrade before and after pyrethroid treatment and correlated it with the number of ticks in the locations. The results showed that tick abundance correlated with GSTs activity. On the other hand, treatment efficiency was location-dependent, being similar in each particular location in both April (spring) and October (autumn). Our results suggest that GSTs activity reflects the influence of both present local allelochemicals from different environmental seasonal vegetation and applied pyrethroid. We can conclude that by evaluating GSTs activity in ticks from particular locations as well as during the treatment with acaricides tick removal practice could be improved.