Effect of hydrogen-rich saline on activity of NLRP3 inflammomes during renal ischemia-reperfusion in mice / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the effect of hydrogen-rich saline on the activity of nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) inflammomes during renal ischemia-reperfusion (I/R) in mice.Methods:Thirty male C57BL/6J mice, weighing 20-25 g, aged 6-8 weeks, were divided into 5 groups ( n=6 each) using a random number table method: sham operation group (S group), I/R group, I/R plus NLRP3 inhibitor MCC950 group (I/R+ M group), I/R plus hydrogen-rich saline group (I/R+ H group), and I/R plus MCC950 plus hydrogen-rich saline group (I/R+ M+ H group). The model of renal I/R injury was established by clipping the bilateral renal pedicles for 30 min followed by reperfusion in anesthetized animals.MCC950 20 mg/kg was intraperitoneally injected for 14 consecutive days before surgery in I/R+ M and I/R+ M+ H groups.Hydrogen-rich saline 5 ml/kg was intraperitoneally injected at 1 h after surgery in I/R+ H and I/R+ M+ H groups.The equal volume of normal sline was given instead in the other groups.Blood samples from hearts were collected at 24 h of reperfusion for determination of concentrations of blood urea nitrogen (BUN), creatinine (Cr) and kidney injury molecule-1 (Kim-1), tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β) and IL-6 in serum (by enzyme-linked immunosorbent assay). The animals were then sacrificed, and kidney tissues were obtained for microscopic examination of pathological changes of renal tissues (with light microscopes) and for determination of cell apoptosis and expression of NLRP3, apoptosis-associated speck-like protein containing C-terminal caspase recruitment domain (ASC) and caspase-1 protein and mRNA (by Western blot or real-time polymerase chain reaction). Results:Compared with group S, the serum concentrations of Cr, BUN, Kim-1, TNF-α, IL-1β and IL-6 were significantly increased, the kidney injury score and the number of apoptotic cells were increased, and the expression of NLRP3, ASC, caspase-1 protein and mRNA was up-regulated in I/R, I/R+ M, I/R+ H and I/R+ M+ H groups ( P<0.05). Compared with group I/R, the serum concentrations of Cr, BUN, Kim-1, TNF-α, IL-1β and IL-6 were significantly decreased, the kidney injury score and the number of apoptotic cells were decreased, and the expression of NLRP3, ASC, caspase-1 protein and mRNA was down-regulated in I/R+ M, I/R+ H and I/R+ M+ H groups ( P<0.05). Compared with group I/R+ H, the serum concentrations of Cr, BUN, Kim-1 and TNF-α, IL-1β and IL-6 were significantly decreased, the kidney injury score and the number of apoptotic cells were decreased, and the expression of NLRP3, ASC, caspase-1 protein and mRNA was down-regulated in group I/R+ M+ H ( P<0.05). Conclusion:The mechanism by which hydrogen-rich saline reduces renal I/R injury is related to inhibiting the activation of NLRP3 inflammomes in mice.