Microbicidal potential evaluation of 1,8-cineole, ?-pinene and p-cymene compounds of essential oil from Protium genus on Leishmania amazonensis in vitro

Submitted by Leticia Schettini (leticia@ufrrj.br) on 2022-03-31T16:57:45Z No. of bitstreams: 1 2019 - Raissa Couto Santana.pdf: 2065280 bytes, checksum: 1266e59f21dbdf6ff5ea36517618a374 (MD5) Made available in DSpace on 2022-03-31T16:57:45Z (GMT). No. of bitstreams: 1 2019 - Raissa Couto Santana.pdf: 2065280 bytes, checksum: 1266e59f21dbdf6ff5ea36517618a374 (MD5) Previous issue date: 2019-02-25 CAPES - Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior Leishmaniases are one of the wide neglected diseases in the world. According to WHO, the number of cases can reach 1.3 million year. The clinical manifestations of these diseases affect humans and animals, being a public and veterinary health problem. The current treatment presents several problems such as difficult of administration, high toxicity and highcosts; besides drug-resistance being observed in many cases. Essential oils are secondary metabolites synthesized by plants, composed of a complex mixture of different substances. In this work, we study in vitro the microbicide potential of 1,8-cineole, p-cymene and ?-pinene compounds present in essential oils of Protium genus on Leishmania amazonensis, one of the etiological agents of cutaneous and diffuse cutaneous leishmaniasis in the New World. Our data showed that treatment of L. amazonensis infected macrophages with the compounds 1,8- cineole, ?-pinene and p-cymene have an anti-amastigote activity. The compounds inhibited the amastigotes survival in a concentration-dependent manner with IC50 of 40 ?g/mL, 50,1 ?g/mL and 41,4 ?g/mL for ?-pinene, p-cymene and 1,8-cineole, respectively. The cytotoxicity for murine macrophages was evaluated by XTT and the results showed that the cells viability remained among 70-95% up to the highest tested concentration (200?g / mL), as well as, their phagocytic capacity was not altered by treatment. Nitric oxide production by macrophages was analyzed because it is a highly toxic molecule for intracellular microorganisms, however, the treatment of resting or LPS-activated macrophages did not modulate NO production by macrophages. Another possible mechanism of action analyzed was the effect of treatment on parasite lipid composition, our results showed that treated L. amazonensis promastigotes had a change in the lipid profile after 48h of treatment at 50 ?g/mL of the compounds. 1,8-cineole treatment decreases around 50% the concentrations of triacylglycerol and sterol + 1.2-diacylglycerol, whereas in fatty acids and 1,3-diacylglycerol there is a tendency of reduction on treated parasites. On the other hand, ?-pinene increased the concentrations of triacylglycerol and sterol sterified by 50% and p-cymene augmented 26% of tryacylglycerol. The results indicate that ?-pinene, p-cymene and 1,8-cineol compounds have anti-Leishmania activity against Leishmania amazonensis. As leishmanioses se encontram entre as mais importantes no grupo das doen?as negligenciadas. Segundo dados da OMS, o n?mero de casos pode chegar a 1,3 milh?o anualmente. As manifesta??es cl?nicas destas doen?as, afligem humanos e animais, sendo um problema de sa?de p?blica e veterin?ria. Os f?rmacos utilizados no tratamento possuem v?rios problemas como administra??o dificultosa, alta toxicidade, custo elevado e al?m disso, casos de resist?ncia tem sido reportados. Os ?leos essenciais s?o metab?litos secund?rios produzidos pelas plantas constitu?dos por uma complexa mistura de diferentes subst?ncias. Neste trabalho estudamos o potencial microbicida dos compostos 1,8-cineol, p-cimeno e ?pineno presentes em ?leos essencias do g?nero Protium sobre o parasito Leishmania amazonensis um dos agentes etiol?gicos da leishmaniose cut?nea e difusa cut?nea no Novo Mundo, in vitro. Nossos dados mostraram que o tratamento com os compostos 1,8-cineol, ?pineno e p-cimeno dos macr?fagos murinos infectados com formas promastigotas de L. amazonensis possui atividade anti-amastigota. Os compostos inibiram a sobreviv?ncia dos amastigotas de forma concentra??o dependente, com IC50 de 40 ?g/mL, 50,1 ?g/mL e 41,4 ?g/mL para ?-pineno, p-cimeno e 1,8-cineol, respectivamente. A avalia??o da citotoxicidade para os macr?fagos murinos foi avaliada por XTT e os resultados mostraram que as c?lulas permaneceram vi?veis entre 70-95 % at? a concentra??o mais alta testada (200?g/mL), assim como sua capacidade fagoc?tica n?o foi alterada pelo tratamento. A produ??o de ?xido n?trico por macr?fagos foi analisada por ser uma mol?cula altamente t?xica para microorganimos intracelulares, no entanto, o tratamento de macr?fagos estimulados ou n?o com LPS, mostrou que estes compostos n?o modulam a produ??o de NO pelos macr?fagos. Outro poss?vel mecanismo de a??o avaliado foi o efeito na composi??o lip?dica dos parasitos tratados, nossos resultados mostraram que promastigotas de L. amazonensis apresentaram uma mudan?a no perfil lip?dico ap?s 48h de tratamento na concentra??o de 50 ?g/mL dos compostos. O tratamento com 1,8-cineol diminuiu as concentra??es de triacilglicerol e esterol + 1.2 diacilglicerol em torno de 50%, enquanto que em ?cidos graxos e 1.3 diacilglicerol h? uma tend?ncia de redu??o nos parasitos tratados. Por outro lado, ?-pineno aumentou as concentra??es de triacilglicerol e esterol esterificado em 50% e p-cimeno aumentou em 26% de triacilglicerol. Os resultados indicam que os compostos ?-pineno, p-cimeno e 1,8-cineol tem atividade anti-Leishmania contra Leishmania amazonensis.