Structural characterization and in vitro myocardial injury protection potential of one acidic polysaccharide from blueberry (Vaccinium spp.) pomace

IntroductionBlueberry pomace is the by–product of blueberry (Vaccinium spp.) fruits. This study aimed to prepare blueberry pomace polysaccharide (BBPP) and explore its myocardial injury protection potential.MethodsAn acidic polysaccharide (BBPP80–1a) was isolated and purified from active BBPP80-1 fraction. Its structure was characterized based on some approaches. Its myocardial injury protection potential was performed in hypoxia/reoxygenation (H/R)-induced H9c2 cells injury model.ResultsThe molecular weight of BBPP80–1a was 164.91 kDa. The ratio of galacturonic acid (GalA) was 50.92% in methylation results. Further, nuclear magnetic resonance data suggested repetitive → 4)-α-D-GalpA-(1 → and → 4)-α-D-GalpA-6-OMe-(1 → residues occupied the homogalacturonan region of backbone. It had a highly porous, reticular, and heterogeneous microstructures. Moreover, BBPP80–1a can obviously protect H9c2 cells from H/R injury via phosphoinositide 3-kinase / protein kinase B / mammalian target of rapamycin (PI3K/AKT/mTOR) and c-Jun N-terminal kinase / mitogen-activated protein kinase (JNK/MAPK) pathways.DiscussionBBPP80–1a is a pectic polysaccharide. It exhibited the potential on cardioprotective effect through the activation of PI3K/AKT/mTOR survival pathway and the regulation of JNK/MAPK pathways.