Sophoricoside from Sophora japonica ameliorates allergic asthma by
preventing mast cell activation and CD4+ T cell differentiation in
ovalbumin-induced mice
Abstract
Background and Purpose: Asthma is a chronic inflammatory lung disorder
with continuously increasing prevalence worldwide. Novel strategies are
needed to prevent or improve asthma. The aim of this study was to
investigate the effects of sophoricoside from Sophora japonica on
allergic asthma. Experimental Approach: Sophoricoside was isolated from
the mature seeds of S. japonica. Allergic asthma and passive cutaneous
anaphylaxis (PCA) models were generated by ovalbumin (OVA) treatment or
antibody-allergen reaction in mice. Allergic and asthmatic symptoms,
immune cell infiltration, and the amounts of histamine, lipid
metabolites, and pro-inflammatory cytokines were determined, and in
vitro CD4+ T cell differentiation was performed. Key Results: The mature
seeds of S. japonica contain a large amount of sophoricoside.
Sophoricoside reduced allergic and asthmatic symptoms by suppressing
airway inflammation and antibody-antigen reaction in mouse models. In
particular, sophoricoside suppressed immune cell recruitment into the
airway lumens of the lungs and production of pro-inflammatory cytokines
in the bronchoalveolar lavage fluid (BALF) of OVA-induced mice. It also
decreased the amounts of histamine and lipid metabolites released in
OVA-induced mice and antibody-antigen stimulated mast cells. In
addition, sophoricoside decreased differentiation of naïve CD4+ T cells
into T helper type 1 (Th1), Th2, and Th17 cells. Conclusions and
Implications: Sophoricoside from S. japonica inhibited allergic asthma
by suppressing mast cell activation and CD4+ T cell differentiation.
Thus, it is a promising candidate molecule for the treatment of allergic
asthma. Keywords Airway inflammation; Allergic asthma; CD4+ T cell; Mast
cell; Ovalbumin; Sophora japonica; Sophoricoside