Comparative Study of Two <i>Erythronium sibiricum</i> Bulb Polysaccharide Fractions in Alleviating Airway Remodeling by Affecting Autophagy and Apoptosis

<i>Erythronium sibiricum</i> (<i>E. sibiricum</i>), 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 <i>E. sibiricum</i> 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, <i>E. sibiricum</i> bulb polysaccharides successfully improved the airway remodeling of asthma. Additionally, ESBP exhibited more potent inhibitory effects on asthmatic defective autophagy than E1P.