Minthostachys verticillata essential oil activates macrophage phagocytosis and modulates the innate immune response in a murine model of Enterococcus faecium mastitis

PAULLIER, VALENTINA CROCE; MOLIVA, MELINA; LAROCQUE-DE-FREITAS, ISABEL FERREIRA; RAVIOLO, JOSÉ MARÍA; MONTIRONI, IVANA DALILA; SIRI, MARÍA INÉS; CAMPRA, NOELIA; DECOTE-RICARDO, DEBORA; CARIDDI, LAURA NOELIA; BEATRIZREINOSO, ELINA; PIANZZOLA, MARÍA JULIA; BAGNIS, GUILLERMO; FREIRE-DE-LIMA, CELIO GERALDO

RESEARCH IN VETERINARY SCIENCE

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2019 vol. 125 p. 333 - 344

0034-5288

Minthostachys verticillata essential oil (EO) is a natural product that reports immunomodulatory effects on humanT cells as well as anti-inflammatory activity. Bovine mastitis is a worldwide disease, mainly caused by bacteria,affecting milk quality and yield, leading to high economic losses. Environmental pathogens, as Enterococcusfaecium, are implicated in the disease. Antibiotic therapy is adequate, although it can leave residues in milk,causing problems in human health. The search of immunomodulatory substances for bovine mastitis treatment isa promising alternative strategy. The aim of this study was to characterize the effect of M. verticillata EO onmacrophage phagocytosis and evaluate its immunomodulatory and protective effects in mice challenged with E.faecium. The results showed that EO activated macrophage phagocytosis mechanisms inducing reactive oxygenspecies production. Moreover, EO modulated the innate immune response in mammary glands of female Balb/cmice challenged with E. faecium decreasing the infiltration of polymorphonuclear neutrophils and IL-1β andTNF-α mRNA expression. In addition, EO increased the expression of IL-10 in the last hours of infection.Treatment with EO did not increase the number of activated CD4+ or CD8+ T cells or the production of specificantibodies. These results suggest that EO play an important role in helping to resolve the infection in the firsthours without activating adaptive immunity. In addition, a marked decrease of the bacterial count in the glandsof mice treated with EO was observed. A natural product such as M. verticillata EO could have a potential use tocontrol bovine mastitis.