Structural characterization and in vitro-vivo evaluation of a polysaccharide from Sanguisorba officinalis on acute kidney injury

We report here an acidic polysaccharide, namely RSP-3, with ameliorating acute kidney injury from Sanguisorba officinalis. We extracted and purified two polysaccharides from this herb based on the acidity and screened them for their effect in regulating the immunology activity of macrophages. Among them, RS-3 exerted the most significant anti-inflammatory activity against lipopolysaccharide (LPS)-stimulated macrophage by decreasing TNF-α and IL-6 levels. Subsequently, we found that RS-3 suppressed ER stress, reducing ROS production and blocking NF-kBp65 translocation. After fully characterized RS-3 with a series of analytical technologies, we tested its anti-acute kidney injury (AKI) effect in vivo. In the murine AKI model induced by lipopolysaccharide (LPS), treatment of RS-3 effectively ameliorated renal function. Besides, it decreased the levels of TNF-α and IL-6 in serum as well as reduced macrophage infiltration in injured kidney tissue. In sum, RSP-3, with solid protective effect against AKI by showing anti-inflammatory activity, may become a meaningful drug candidate for treatment of AKI.