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Objective To observe the role and related mechanism of chemerin and its receptor ChemR23 in glomerular endothelial cells (GEnCs) stimulated by high glucose.Methods Mouse GEnCs were cultured and divided into control group,20.0 mmol/L high glucose group,40.0 mmol/L high glucose group and mannitol control group.Then the expressions of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in cell culture supematant as well as the expressions of intracellular protein and mRNA of chemerin,ChemR23,IL-6 and TNF-α were detected.Lentiviral transfection targeting ChemR23 was applied before high glucose-or Chemerin-stimulated,and expressions of supernatant and intracellular mRNA of IL-6 and TNF-α were measured.Meanwhile whether p38 mitogen-activated protein kinase (p38 MAPK) pathway was activated by high glucose was detected.The specific inhibitor of p38 MAPK was added prior to high glucose-stimulated,then supernatant and intracellular mRNA expressions of IL-6 and TNF-α was detected.The supernatant expressions of IL-6 and TNF-α were measured by ELISA.The intracellular protein expression and p38 MAPK phosphorylation activity were detected by Western blotting.The mRNA expression was detected by real time PCR.Results Compared with those in the control group,in high glucose groups the expressions of IL-6,TNF-α and chemerin were significantly increased (all P ＜ 0.05),however,the expressions of ChemR23 did not change (all P ＞ 0.05);the supernatant and mRNA expressions of IL-6 and TNF-α were also elevated in the chemerin group (all P ＜ 0.05).Lentivirus baring shRNA could efficiently suppress ChemR23 expression,and the Chemerin-or high glucose-induced expressions of IL-6 and TNF-α were reduced (all P ＜ 0.05).Also it could significantly reduce the expression of phosphorylated-p38 MAPK (p-p38 MAPK) induced by high glucose (P ＜ 0.05),as high glucose group had higher p-p38 MAPK than control group (P ＜ 0.05).While the high glucose-elevated expressions of IL-6 and TNF-α were significantly attenuated by p38 MAPK inhibitor (all P ＜ 0.05).Conclusions High glucose stimulation can induce the expression of chemerin in GEnCs.By binding to ChemR23,chemerin activates p38 MAPK signaling pathway,and then promotes the expressions of IL-6 and TNF-α.These inflammatory cytokines aggravate inflammation of GEnCs.
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<p><b>OBJECTIVE</b>To study the protective effects of sacral nerve root electrostimulation on intestinal mechanical barrier in rats with spinal cord injury (SCI).</p><p><b>METHODS</b>Fifty six Wistar rats were divided into normal group, SCI control group and SCI group with sacral nerve root electrostimulation (8 rats in each subgroup at 24, 48, 72 h after spinal cord injury). The following experiments were performed respectively in rats from the 3 groups: bacteria culture from intestinal mesentery lymph nodes, liver, spleen, intestinal morphology observation and detection the protein expression level of ZO-1.</p><p><b>RESULTS</b>The intestinal mucosa appeared different degree of damage in SCI control group; cell-cell connections between intestinal epithelial cells were destroyed; Endotoxin levels in blood and the number of bacterial translocation increased obviously. Sacral nerve stimulation was found toimprove the intestinal mucosal, reduce the endotoxin content in the blood to normal level and the decrease the incidences of bacterial translocation of the gut origin. The expression of tight junction protein ZO-1 of rat intestinal tissue had no statistical differences among the 3 groups. On the other hand, the distribution of tight junction protein ZO-1 appeared different degrees of scattered and irregular in the control group while that in the experimental group appeared different degree of improvement as determined by the immunohistochemistry of rat intestinal tissue.</p><p><b>CONCLUSION</b>sacral nerve root electrostimulation can rehabilitate the peristalsis of denervated colon, promote defeacation and decrease bacterial amount, protection of the intestinal mechanical barrier between intestinal epithelial cells and tight junction, reducing the endotoxin content in the blood and suppressing bacterial translocation from the gut.</p>