Proceedings of The Physiological Society

Europhysiology 2018 (London, UK) (2018) Proc Physiol Soc 41, PCA073

Poster Communications

Oral anethole improves respiratory function in an ovalbumin-induced asthma model

D. S. Serra2, F. S. Cavalcante2, W. A. Zin1, J. H. Leal-Cardoso2

1. Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil. 2. Physiological Sciences Department, State University of Ceara, Fortaleza, Brazil.

Croton zehntneri Pax et Hoffm. is a Euphorbiaceae species, popularly known as "canela de cunhã", a native plant from Northeastern Brazil that produces anethole, an essential oil popularly used as an anti-inflammatory and antioxidant agent. Due to its importance and complexity, asthma has been extensively studied. However, numerous questions related to its pathophysiology have not been answered yet, and the development of new therapeutic agents has been limited. The present study investigated the therapeutic outcomes of anethole in an OVA-induced asthma model. The study was approved by our institutional animal ethics committee (Ceará State University, N° 3114549/2014). 32 BALB/c mice were used, randomly divided into four groups (n=8). Two groups were sensitized and challenged with saline and treated with oral anethole (300 mg/kg) (SA) or Tween 80 0.1% (ST). The OT and OA groups were sensitized and challenged with ovalbumin and treated with oral anethole (300 mg/kg) (OA) or Tween 80 0.1% (OT). 24 hours after the treatment, the animals were anesthetised with sodium pentorbarbital (50 mg/kg, i.p., Hypnol® 3%, Syntec, Brazil), tracheosthomised, connected a mechanical ventilator, and paralysed with pancuronium bromide (0.5 mL/kg, i.p., Cristália, Brazil). Respiratory mechanics was assessed by the forced oscillation technique and quasi-static PV (pressure-volume) curve. Values are means ± S.D., compared by ANOVA. The respiratory mechanical properties determined by the forced oscillation technique were: Newtonian resistance (RN): ST = 0.143±0.015, SA=0.134±0.022, OT=0.252±0.047 and OA=0.159±0.034 cmH2O/mL/s; tissue damping (G): ST=3.31±0.38, SA=3.14±0.36, OT=6.41±1.02 and OA=3.37±0.47 cmH2O/mL; and tissue elastance (H) ST=12.27±1.56, SA=12.13±1.53, OT=21.36±2.40 and OA=13.10±1.47 cmH2O/mL. The pressure-volume (PV) curve led to an estimated inspiratory capacity (IC) of: ST=1.15±0.16, SA=1.17±0.15, OT=0.79±0.13 and OA=1.11±0.20 mL; static compliance (CST) of: ST=0.123±0.010, SA=0.125±0.011, OT=0,072±0,016 and OA=0.115±0.022 mL/cmH2O; and PV loop area of: ST=2.30±0.48, SA=2.21±0.48, OT=4.03±0.74 and OA=2.41±0.55 cmH2O.mL). We found significant impairment (p<0.05) in all respiratory mechanics parameters in OT mice compared to the ST group, thus confirming the OVA-induced lung injury. The comparison of OA with OT (p<0.05) demonstrated that anethole was able to improve respiratory function in the OVA-induced asthma group. In conclusion, our results demonstrated that anethole was able to improve the respiratory function in the OA group compared with OT. The present study serves as a starting point for conducting research with anethole to validate its putative use as an alternative asthma therapy. Supported by: CAPES, FUNCAP, CNPq, FAPERJ

Where applicable, experiments conform with Society ethical requirements