title: In vitro and in vivo action of terpinen-4-ol, γ-terpinene, and α-terpinene against Trypanosoma evansi.
abstract: This study aimed to evaluate the susceptibility in vitro and in vivo of Trypanosoma evansi to terpinen-4-ol, γ-terpinene and α-terpinene, the three main compounds of tea tree oil (Melaleuca alternifolia) with known efficacy in the treatment of trypanosomosis. In vitro, a trypanocidal effect of terpinen-4-ol, γ-terpinene, and α-terpinene was observed when used alone or associated at 0.5, 1 and 2% concentrations i.e., the α-terpinene showed a faster trypanocidal effect when compared to chemotherapy (diminazene aceturate - D.A.). In vivo studies were performed in two experiments: I and II where experiment I used T. evansi infected mice treated with terpinen-4-ol, γ-terpinene and α-terpinene alone (at a dose of 1.0 mL kg(-1)) or associated (two compounds, dose of 0.5 mL kg(-1) of each compound; tree compounds, dose of 0.335 mL kg(-1) of each compound); Treatment with α-terpinene was able to extend animal longevity, but showed no curative efficacy. In experiment II, T. evansi infected mice were treated with D.A. associate with α-terpinene, where a curative efficacy of 57.14% was found, a much better result when D.A. was used alone (14.28%). In summary, α-terpinene associated with D.A. can be used as an alternative treatment for T. evansi infection. The compound α-terpinene from M. alternifolia essential oil is the one responsible for the trypanocidal effect, a fact confirmed by in vitro results and the increased longevity observed on treated mice.
authors.affiliation: Department of Microbiology and Parasitology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil. Electronic address: matheusd.biomed@yahoo.com.br.
authors.forename: Matheus D
authors.initials: MD
authors.lastname: Baldissera
authors.affiliation: Department of Microbiology and Parasitology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil.
authors.forename: Thirssa H
authors.initials: TH
authors.lastname: Grando
authors.affiliation: Department of Physiology and Pharmacology (UFSM), Santa Maria, RS, Brazil.
authors.forename: Carine F
authors.initials: CF
authors.lastname: Souza
authors.affiliation: Department of Microbiology and Parasitology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil.
authors.forename: Lucas T
authors.initials: LT
authors.lastname: Gressler
authors.affiliation: Department of Animal Science, Universidade do Estado de Santa Catarina (UDESC), Chapecó, SC, Brazil.
authors.forename: Lenita M
authors.initials: LM
authors.lastname: Stefani
authors.affiliation: Department of Animal Science, Universidade do Estado de Santa Catarina (UDESC), Chapecó, SC, Brazil.
authors.forename: Aleksandro S
authors.initials: AS
authors.lastname: da Silva
authors.affiliation: Department of Microbiology and Parasitology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil. Electronic address: sgmonteiro@uol.com.br.
authors.forename: Silvia G
authors.initials: SG
authors.lastname: Monteiro
mesh_terms: D000818:Animals; D000081005:Cyclohexane Monoterpenes; D004133:Diminazene / Q000031:analogs & derivatives / Q000494:pharmacology / Q000627:therapeutic use; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D005260:Female; D051379:Mice; D039821:Monoterpenes / Q000494:pharmacology* / Q000627:therapeutic use; D051381:Rats; D013729:Terpenes / Q000494:pharmacology* / Q000627:therapeutic use; D014344:Trypanocidal Agents / Q000494:pharmacology* / Q000627:therapeutic use; D014345:Trypanosoma / Q000187:drug effects*; D014352:Trypanosomiasis / Q000188:drug therapy* / Q000469:parasitology
chemical_list: D000081005:Cyclohexane Monoterpenes; D039821:Monoterpenes; D013729:Terpenes; D014344:Trypanocidal Agents; C018669:gamma-terpinene; C034019:terpinenol-4; C003915:diminazene aceturate; D004133:Diminazene
keywords: Majority compounds; TTO; Trypanosomosis; α-terpinene