Structural characterization and hepatoprotective activities of polysaccharides from Campanumoea javanica Bl

Campanumoea javanica Bl. is a traditional herb used in Southwestern China for its "Qi-invigorating" and immune-strengthening properties. An acidic pectic heteropolysaccharide, CJPC, was isolated from its roots by hot water extraction followed by DEAE Sepharose Fast Flow and Sephacryl S-200 HR chromatography. CJP-C had a weight-average molecular weight of 32.6 kDa and consisted mainly of galactose, galacturonic acid, arabinose, and rhamnose (molar ratio 2.53:1.86:1.03:1.00). Its backbone comprised a homogalacturonan (HG) domain of α-1,4-linked GalpA residues and an RG-I domain of alternating α-1,4-GalpA and α-1,2-Rhap residues, the latter branched at O-4 of rhamnose with β-1,4-galactan, β-1,6-galactan, and α-1,5-arabinan side chains. Crude CJP and purified CJP-C showed broadly comparable immunomodulatory and antioxidant activities in vitro. In a Con A-induced autoimmune hepatitis mouse model, CJP (1200 mg/kg) significantly reduced serum ALT/AST, alleviated hepatic necrosis and inflammation, restored SOD and GSH-Px activities, lowered MDA, and suppressed IL-6, IL-1β, IFN-γ, MIP-1α, and ICAM-1. CJP treatment was associated with reduced total STAT1 protein expression, while T-bet levels were unchanged and SOCS1, a direct STAT1 target, was downregulated. These findings indicate that CJP alleviates Con A-induced hepatic injury, an effect associated with reduced oxidative stress and suppression of inflammatory signaling involving the IFN-γ/STAT1 axis, supporting its potential as a functional food or adjunctive therapy pending further validation.