Ethyl p-methoxycinnamate isolated from Kaempferia galanga L. rhizome reduces airway remodeling in asthmatic rat models

Abstract

Background: Asthma causes changes in the airway structure called airway remodeling due to chronic inflammatory reactions. Transforming Growth Factor-β (TGF-β) is one of the inflammatory mediators which has a significant role in the remodeling and inflammatory process. One of the medicinal plants known to have anti-inflammatory potential is Kaempferia galanga L. This study aims to analyze the effect of ethyl p-methoxycinnamate isolated from Kaempferia galanga L. rhizome on the expression of TGF-β and fibrosis in the bronchial mucosa of asthmatic rat models. Methods: We conducted an experimental laboratory study using the posttest only control group design. Thirty-six Wistar male white rats were allocated into six groups, NC (negative control), PC (positive control), T1 (treatment group), T2 (treatment group), T3 (treatment group), and T4 (treatment group) receiving 1% ovalbumin in alum (OVA); 1% OVA as well as 1 mg/kg steroid; 1% OVA, 1 mg/kg steroid, and 200 mg/kg ethyl p-methoxycinnamate isolated from Kaempferia galanga L. rhizome (KG-EPMC); 1% OVA, 1 mg/kg steroid, and 400 mg/kg KG-EPMC; 1% OVA and 200 mg/kg KG-EPMC; and 1% OVA as well as 400 mg/kg KG-EPMC, respectively. Data were analyzed with SPSS version 22.0 for Windows. Results: The expressions of TGF-β and fibrosis were significantly lower in positive control as well as treatment groups than those of the negative control group (only receiving OVA) (p<0.05). There were no significant differences between positive control and treatment groups regarding TGF-β level and fibrosis (p>0.005). Conclusion: Ethyl p-methoxycinnamate isolated from Kaempferia galanga L. rhizome exhibits antiasthma effect by reducing the expression of TGF-β and fibrosis in the bronchial mucosa of an asthmatic rat model. Hence, it can be a potential therapy for asthma.