title: Relationship between glutathione S-transferase, catalase, oxygen consumption, lipid peroxidation and oxidative stress in eggs and larvae of Boophilus microplus (Acarina: Ixodidae).
abstract: Glutathione S-transferases (GSTs) are enzymes that act in excretion of physiologic and xenobiotic substances, protecting cells against chemical toxicity and stress. In this work, we characterized the enzymatic activity of GST in eggs and larvae of cattle tick Boophilus microplus, on different days after oviposition and eclosion. The results showed that the GST activity varied depending on the time elapsed after oviposition and eclosion. Molecules involved in mechanism of protection from oxidative stress are correlated with the increase in GST activity. The oxygen consumption kinetics showed a positive correlation with the increase in GST activity during embryogenesis. A high content of thiobarbituric acid reactive substances were observed in egg and larva extracts, indicating that ticks face high oxidative stress during embryogenesis and aging. In eggs and larvae, GST activity can be correlated to kinetic parameters of oxidative stress such as catalase and glutathione. In addition, GST activity showed strong positive correlation with lipid peroxidation, an indication that it plays a role in oxidant defences in eggs.
authors.affiliation: Centro de Biotecnologia do Estado do Rio Grande do Sul, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, C. P. 15005, 91501-970 Porto Alegre, RS, Brazil.
authors.forename: D R J
authors.initials: DR
authors.lastname: Freitas
authors.forename: R M
authors.initials: RM
authors.lastname: Rosa
authors.forename: J
authors.initials: J
authors.lastname: Moraes
authors.forename: E
authors.initials: E
authors.lastname: Campos
authors.forename: C
authors.initials: C
authors.lastname: Logullo
authors.forename: I
authors.initials: I
authors.lastname: Da Silva Vaz
authors.forename: A
authors.initials: A
authors.lastname: Masuda
mesh_terms: D000640:Amitrole / Q000494:pharmacology; D000818:Animals; D002374:Catalase / Q000037:antagonists & inhibitors / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D005978:Glutathione / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D026863:Ixodidae / Q000378:metabolism*; D007814:Larva / Q000378:metabolism; D015227:Lipid Peroxidation; D010063:Ovum / Q000378:metabolism*; D018384:Oxidative Stress; D010101:Oxygen Consumption
chemical_list: D004791:Enzyme Inhibitors; D002374:Catalase; D005982:Glutathione Transferase; D005978:Glutathione; D000640:Amitrole