title: Oral Bromelain Attenuates Inflammation in an Ovalbumin-induced Murine Model of Asthma.
abstract: Bromelain, a widely used pineapple extract with cysteine protease activity, has been shown to have immunomodulatory effects in a variety of immune system models. The purpose of the present study was to determine the effects of orally administered bromelain in an ovalbumin (OVA)-induced murine model of acute allergic airway disease (AAD). To establish AAD, female C57BL/6J mice were sensitized with intraperitoneal (i.p.) OVA/alum and then challenged with OVA aerosols for 3 days. Mice were gavaged with either (phosphate buffered saline)PBS or 200 mg/kg bromelain in PBS, twice daily for four consecutive days, beginning 1 day prior to OVA aerosol challenge. Airway reactivity and methacholine sensitivity, bronchoalveolar lavage (BAL) cellular differential, Th2 cytokines IL-5 and IL-13, and lung histology were compared between treatment groups. Oral bromelain-treatment of AAD mice demonstrated therapeutic efficacy as evidenced by decreased methacholine sensitivity (P </= 0.01), reduction in BAL eosinophils (P </= 0.02) and IL-13 concentrations (P </= 0.04) as compared with PBS controls. In addition, oral bromelain significantly reduced BAL CD19+ B cells (P </= 0.0001) and CD8+ T cells (P </= 0.0001) in AAD mice when compared with controls. These results suggest that oral treatment with bromelain had a beneficial therapeutic effect in this murine model of asthma and bromelain may also be effective in human conditions.
authors.affiliation: Department of Immunology and Department of Pediatrics, University of Connecticut School of Medicine, Farmington, CT, USA.
authors.forename: Eric R
authors.initials: ER
authors.lastname: Secor
authors.forename: William F
authors.initials: WF
authors.lastname: Carson
authors.forename: Anurag
authors.initials: A
authors.lastname: Singh
authors.forename: Mellisa
authors.initials: M
authors.lastname: Pensa
authors.forename: Linda A
authors.initials: LA
authors.lastname: Guernsey
authors.forename: Craig M
authors.initials: CM
authors.lastname: Schramm
authors.forename: Roger S
authors.initials: RS
authors.lastname: Thrall