ABSTRACT: Polysaccharide extracted from Polygonatum odoratum ameliorates acute lung injury in mice by reducing immuno-inflammation and modulating gut microbiota.
Project description:Nlrp6-/- lamina propria Ly6C-hi monocytes in response to AOM/DSS have deficient TNFα production, but increased production of other pro-inflammatory cytokines as compared to WT NLRP6 is a member of the Nod-like receptor family, whose members are involved in the recognition of microbes and/or tissue injury. NLRP6 was previously demonstrated to regulate the production of IL-18 and is important for protecting mice against chemically-induced intestinal injury and colitis-associated colon cancer. However, the cellular mechanisms by which NLRP6 reduces susceptibility to colonic inflammation remain unclear. Here, we determined that NLRP6 expression is specifically upregulated in Ly6Chi inflammatory monocytes that infiltrate into the colon during dextran sulfate sodium (DSS)-induced inflammation. Adoptive transfer of WT Ly6Chi inflammatory monocytes into Nlrp6-/- mice was sufficient to protect them from mortality, significantly reducing intestinal permeability and damage. NLRP6-deficient inflammatory monocytes were specifically defective in TNFα production, which was important for reducing DSS-induced mortality and dependent on autocrine IL-18 signaling by inflammatory monocytes. Our data reveal a previously unappreciated role for NLRP6 in inflammatory monocytes, which are recruited during intestinal injury to promote barrier function and limit bacteria-driven inflammation. This study also highlights the importance of early cytokine responses, particularly NLRP6-dependent and IL-18-dependent TNFα production in preventing chronic dysregulated inflammation. Ly6Chi monocytes were sorted from lamina propria of WT or Nlrp6-/- mice at day 10 of AOM/2%DSS. RNA was extracted and hybridized to the mouse 2.1 ST array.
Project description:Peripheral nerve injury (PNI) results in loss of neural control and severe disabilities in patients. Promoting functional nerve recovery by accelerating angiogenesis is a promising neuroprotective treatment strategy. Here, we identified a bioactive Radix Astragalus polysaccharide (RAP) extracted from traditional Chinese medicine (TCM) as a potent enhancer of axonal regeneration and remyelination. Notably, RAP promoted functional recovery and delayed gastrocnemius muscle atrophy in a rat model of sciatic nerve crush injury. Further, RAP treatment induced angiogenesis in vivo. Moreover, our in vitro results showed that the role of RAP in endothelial cell (EC) migration and tube formation was probably related to the activation of AKT/eNOS signaling pathway. Altogether, our results show that RAP can enhance functional recovery by accelerating angiogenesis, thereby providing a polysaccharide-based therapeutic strategy for PNI.
