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

Ethnopharmacological relevance: Cassia 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 study: To explore the anti-inflammatory potential of AQs extracted from C. occidentalis using an in vivo model of ovalbumin (OVA)-induced asthma. Materials and methods: Extraction 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 Thl/Th2 cytokine (IL-4, IL-5, IL-13 and IFN-gamma) 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. Thl/Th2 cytokine mRNA expression was analyzed using the 2(-Delta Delta ct) method. Results: Treatment 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,Thl cytokine IFN-y production in BALF was promoted. AQs also decreased mRNA expression of Thl/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. Conclusions: These findings demonstrated the inhibitory effects of AQs, derived from C. occidental is, on OVA induced allergic asthma in mice. The results suggest a promising ethnopharmacological use for AQs in patients with asthma.