Inhibitory effects of an extract mixture of ivy (Hedera helix) leaves and Coptidis rhizoma on ovalbumin-induced allergic lung inflammation by co-exposure to Asian sand dust in mice

Abstract

Asian sand dust (ASD) is known to cause adverse respiratory health disorders, but there is no beneficial strategiesfor preventing harmful health effects by ASD. This study aimed to evaluate the inhibitory effects of a combined extractmixture of ivy leaves and Coptidis rhizoma on allergic lung inflammation responses to ASD. Allergic lung inflammation wasevoked with ovalbumin (OVA) or OVA plus ASD in a murine asthma model. ASD significantly enhanced allergic lung inflammationin the airway hyperresponsiveness and pathologic changes of the lung in mice compared to the vehicle and OVA controls. Oral administration of a combined extract mixture of ivy leaves and Coptidis rhizoma significantly decreased theinfiltration of eosinophils and lymphocytes, and suppressed the releases of Th2 cytokines (IL-4 and IL-5) and chemokine(MCP-1) in bronchoalveolar lavage fluid compared with OVA plus ASD. The anti-inflammatory effect of the extract mixture(25 to 100 mg/kg, p.o.) was similar to that of dexamethasone (1 mg/kg, p.o.). This study suggested a novel insight into thepathological mechanisms underlying the inhibition of ASD-induced allergic asthma via suppression of eosinophilic inflammatorymediators release for the development of new strategies in preventing of the eosinophilic bronchial asthma causedby air-borne dust.