Amelioration of airway inflammation and pulmonary edema by Teucrium stocksianum via attenuation of pro-inflammatory cytokines and up-regulation of AQP1 and AQP5

Abstract

Current study investigates the immunomodulatory effects of T. stocksianum using mouse model of ovalbumin (OVA)-induced allergic asthma. The mice were treated with methanolic extract, n-hexane, and ethyl acetate fractions for consecutive 7 days along with intranasal challenge. The mRNA expression levels of interleukin-4 (IL-4), IL-5, Aquaporin-1 (AQP1) and Aquaporin-5 (AQP5) were evaluated using reverse transcription polymerase chain reaction. The data showed that T. stocksianum significantly reduced airway inflammation as indicated by reduced inflammatory cell infiltration in lungs, and attenuated total and differential leukocyte counts both in blood and BALF. Expression levels of pro-inflammatory IL-4 and IL-5 in lungs were also found significantly reduced. T. stocksianum significantly reduced pulmonary edema as indicated by reduced lung wet/dry ratio and goblet cell hyperplasia. AQP1 and AQP5 expression levels were also found elevated in treatment groups. In conclusion, T. stocksianum possesses anti-asthmatic activity which may be attributed to reduction in IL-4 and IL-5 expression levels, and elevation in AQP1 and AQP5 expression levels.

Keywords: Interleukin-5; airway inflammation; aquaporins; interleukin-4; pulmonary edema.