In vitro evaluation of the acaricidal activity of ozone/ozonized oil on tick cells (RSE8 and IDE8) infected and not infected with Ehrlichia canis

• Grant number: 21/10773-3
• Support type: Scholarships abroad - Research Internship - Doctorate
• Effective date (Start): January 10, 2022
• Effective date (End): April 09, 2022
• Field of knowledge: Biological Sciences - Zoology - Applied Zoology
• Principal researcher: Maria Izabel Souza Camargo
• Grantee: Marina Rodrigues de Abreu
• Supervisor abroad: Ana Isabel Amaro Gonçalves Domingos
• Home Institution: Instituto de Biociências (IB). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil
• Research place: Universidade Nova de Lisboa, Portugal
• Associated to the scholarship: 18/02999-9 - In vitro and in vivo action of ozone on embryonic lineage cells (RML RSE and RML-15) and R. sanguineus s. l. semi engorged females, BP.DR

Abstract

The species Rhipicephalus sanguineus l.s. popularly known as the "dog tick", it has great veterinary medical importance, as, in addition to despoiling its hosts, it can be a vector of pathogens that affect domestic animals and humans, including the intracellular bacteria Ehrlichia canis, responsible for Monocytic Ehrlichiosis Canine (EMC), one of the most important in the veterinary field. Numerous studies have been conducted in search of effective methods to control this tick, prioritizing, in addition to the safety of non-target animals, human health, minimizing the generation of environmental waste, but emphasizing that they must be efficient against the ectoparasite. In this context, ozone, an oxidizing agent that can be used in various formulations (dissolved in water, oil, etc.) has been shown to be a potential acaricide on the species R. sanguineus l.s. (in vivo), since exposure tests with ozonized water changed morphophysiologically the integument, salivary glands, ovaries and gene organ of females of this species of ticks. Despite the encouraging results obtained in the laboratory, there are still questions to be answered regarding the acaricide effect of ozone at the cellular and molecular levels. Therefore, it is proposed the in vitro study of the acaricide action potential of ozone (ozonized sunflower oil) on embryonic cell lines of ticks (IDE8 and RSE8) infected and not infected with E. canis in order to clarify the cellular and molecular mechanisms that result from this exposure, including on the pathogens transmitted by these ticks, carrying out qPCR analyzes for cellular stress and apoptosis genes (GST and Caspases 1/8), as well as carrying out morphological analyzes of the cells under light microscopy for analysis of infection. (AU)