Effects of anthraquinones from Cassia occidentalis L. on ovalbumin-induced airways inflammation in a mouse model of allergic asthma

Abstract

Ethnopharmacological relevanceCassia occidentalis Linn. is a traditional ayruvedic edible shrub containing anthraquinones (AQs) as the principle active constituents. In folk medicine, it has a variety of uses including treatment of whooping cough (‘pertussis’) and inflammatory diseases. Despite these applications, limited data are available to validate the effects of C. occidentalis AQs on airways inflammation in asthma. Aim of the studyTo explore the anti-inflammatory potential of AQs extracted from C. occidentalis using an in vivo model of ovalbumin (OVA)-induced asthma. Materials and methodsExtraction and optimization of AQs from C. occidentalis was performed by mechanochemistry. Allergic asthma in BALB/c mice was sensitized and challenged by OVA, and the effects of AQs investigated in a mouse model. OVA-specific IgE concentrations in serum, and Th1/Th2 cytokine (IL-4, IL-5, IL-13 and IFN-γ) concentrations, inflammatory cell counts and classification in bronchoalveolar lavage fluid (BALF) were determined. Histopathological evaluation of lung tissue was performed using hematoxylin and eosin (H&E), and periodic acid-schiff (PAS) staining. Th1/Th2 cytokine mRNA expression was analyzed using the 2-ΔΔCt method. ResultsTreatment with AQs decreased inflammatory cell counts and production of Th2 cytokines (IL-4, IL-5 and IL-13) in BALF, and OVA-specific IgE in serum. In contrast,Th1 cytokine IFN-γ production in BALF was promoted. AQs also decreased mRNA expression of Th1/Th2 cytokine in lung tissue. Histological studies demonstrated that AQs substantially inhibited OVA-induced cellular infiltration, mucus hypersecretion and goblet cell hyperplasia in the lung. ConclusionsThese findings demonstrated the inhibitory effects of AQs, derived from C. occidentalis, on OVA-induced allergic asthma in mice. The results suggest a promising ethnopharmacological use for AQs in patients with asthma.