Paeoniae radix alba polysaccharides obtained via optimized extraction treat experimental autoimmune hepatitis effectively

The extraction process of Paeoniae radix alba polysaccharides (PRAP) was optimized as the liquid-solid ratio of 10.65 mL/g, the extraction time of 2.10 h, and the 2 extraction repetitions through a response surface methodology. The chemical profiles of the obtained PRAP were characterized by measuring the contents of total carbohydrates, total phenolics, uronic acid and protein, and by analyzing the FT-IR spectrum and monosaccharide composition. To determine the therapeutic effects of PRAP on experimental autoimmune hepatitis (EAH), we established an EAH mice model. After treated with PRAP, liver and spleen injuries were reduced, and hepatocyte regeneration and liver function were improved. Further study of the mechanism by which PRAP treats EAH showed that PRAP significantly inhibited oxidative stress in the livers of EAH model mice. More importantly, PRAP inhibited immune inflammatory reactions in EAH model mice, including the hepatic infiltration of inflammatory CD4+ and CD8+ T cells, as well as overexpression of inflammatory cytokines IL-2, IL-6 and IL-10, via inhibition of the NF-κB signaling pathway. •The optimal extraction process of PRAP has been determined by response surface methodology.•PRAP could recover the liver function and damages of EAH mice.•PRAP treat EAH in mice by inhibiting immune inflammatory reaction.