Comparative Study of Two Erythronium sibiricum Bulb Polysaccharide Fractions in Alleviating Airway Remodeling by Affecting Autophagy and Apoptosis.

Abstract

Erythronium sibiricum (E. sibiricum), which is an indigenous herb in China, is gathered and consumed by nomads in Xinjiang due to its medicinal value. Only a few studies have evaluated its possible pharmacological activity. This study aims to examine and compare the ways in which two E. sibiricum bulb polysaccharide fractions (ESBP and E1P) alleviate airway remodeling based on apoptosis and autophagy. In a mouse model of chronic asthma produced by ovalbumin, the anti-asthmatic effects of E1P and ESBP were investigated. The expression levels of the proteins linked to autophagy and apoptosis (cleaved-caspase 3, Beclin1, LC3B, Bad, and Bax) as well as the activity of the PI3K/Akt/mTOR signaling pathway were assessed. Airway remodeling was alleviated by E1P and ESBP. While E1P could only prevent the increase in PI3K, ESBP was capable of inhibiting the PI3K/Akt/mTOR signaling pathway. Furthermore, ESBP decreased the levels of cleaved-caspase 3, Beclin1, LC3B, Bad, and Bax protein expressions. By modifying signaling pathways linked to autophagy and apoptosis, E. sibiricum bulb polysaccharides successfully improved the airway remodeling of asthma. Additionally, ESBP exhibited more potent inhibitory effects on asthmatic defective autophagy than E1P.