Optimization extraction of Allium mongolicum Regel polysaccharide and alleviation of intestinal injury via inhibition of the PERK/ATF4/CHOP signaling pathway

Introduction This study aimed to optimize the extraction conditions of Allium mongolicum Regel polysaccharides ( AMRP ) and investigate how AMRP alleviates diquat ( DQ )-induced intestinal injury by modulating endoplasmic reticulum stress (ERS). Methods This experiment consisted of two parts. 1)Optimizing the optimal extraction conditions for AMRP using single-factor experiments combined with response surface methodology (RSM).2) In vivo experiment: A total of 36 specific pathogen-free (SPF) mice were selected and randomly divided into 3 treatment groups, namely the control group (CON), diquat group (DQ), and AMRP + diquat challenge group (AMRP+DQ). The experiment included a 7-day pre-feeding period and a 21-day formal trial period, during which the mice had free access to drinking water and feed. Mice in the AMRP+DQ group were gavaged with 0.2 ml of AMRP solution at a concentration of 80 mg/ml, while mice in the CON and DQ groups were gavaged with the same volume of normal saline. One day before the end of the experiment, mice in the DQ and AMRP+DQ groups were subcutaneously injected with DQ solution at a concentration of 10 mg/kg body weight (BW). After a 12-h fast, the mice were slaughtered for sample collection. Results Supplementation with AMRP significantly increased thymus and spleen indices, improved intestinal morphology, markedly reduced serumlevels of pro-inflammatory cytokines ( P < 0.05), elevated serum anti-inflammatory factors ( P < 0.05), and decreased pro-inflammatory cytokine levels in intestinal tissues of DQ-challenged mice. Conclusion AMRP suppressed the expression of key factors in the ERS signaling pathway (PERK/ATF4/CHOP). In conclusion, the optimal extraction conditions for AMRP were 25% papain, 4.5 h hydrolysis, and 63 °C. AMRP effectively reduced inflammation, alleviated DQ -induced intestinal injury via the PERK/ATF4/CHOP pathway, and enhanced growth performance and immune function in DQ challenged mice. This study provides new insights into the anti-inflammatory potential of plant polysaccharides and their ability to alleviate intestinal injury.