The Mechanism Research Of Renal Protective Effect Of Aspirin-triggered Lipoxins In Acute Kidney Injury

Objective:Based on the construction of lipopolysaccharide(LPS)-induced acute kidney injury(AKI)model of mouse and cell injury,we had observed the effect of aspirin triggered lipoxin(ATL)on secretion of inflammatory cytokines and AKI biomarkers in AKI mice and human renal proximal tubular epithelial cells(HK2),and the influence of TLR4/MyD88/NF-B signaling pathway.In order to investigate the mechanism of renal protective effects of ATL.Methods:(1)Forty male C57BL/6J mice were randomly divided into five groups(n=10/group):control group,LPS 6h group,LPS 12h group,ATL+LPS 6h group,ATL+LPS 12h group.Control group mice were received intraperitoneal injection of 4ml/kg NS,the other four groups mice were given intraperitoneal injection of 10mg/kg LPS so as to build AKI animal model.ATL+LPS groups was given intraperitoneal injection of 5μg ATL 2h before LPS injection.At time 6h and 12h after LPS injection,blood,urine and renal tissue samples were collected separately.Levels of Scr,BUN,serum inflammatory factors(TNF-a,IL-1β,IL-6,IL-8),AKI biomarker(NGAL,KIM-1,netrin-1,L-FAPB)and the expression of TLR4/MyD88/NF-B signaling pathway related proteins in renal tissue were detected.(2)HK2 cells were randomly divided into 3 groups:control group,LPS group,ATL+LPS group.Control group was given 1μg/ml PBS 1ml,the other two groups were given 1 pg/ml LPS 0.5ml,and ATL+LPS group was given 100nM concentration of ATL 0.5ml 1h before LPS.24h after LPS was given,cells morphology were observed under inverted microscope,and cells were collected and the expression of TLR4/MyD88/NF-B signaling pathway related proteins in cells were detected.Results:(1)Compared with the control group,the levels of Scr,BUN,serum inflammatory factors(TNF-α,IL-1β,IL-6,IL-8),AKI biomarker(NGAL,KIM-1,netrin-1,L-FAPB)in LPS groups were significantly increased(P<0.01).Compared with the LPS groups,the levels of Scr,BUN,serum inflammatory factors(TNF-α,IL-1β,IL-6,IL-8),AKI biomarker(NGAL,KIM-1,netrin-1,L-FAPB)in ATL+LPS groups were significantly decreased(P<0.01).Pathological changes of kidney tissue:control group showed normal glomerular morphology,mesangial cells and renal tubular,LPS groups showed augmented glomerular volume,proliferative mesangial cells and stroma,inflammatory cells infiltrative in renal interstitial area,and renal tubular showed extensive expansion,edema,epithelial cells showed necrosis,shedding and vacuolar degeneration.There were slight changes of glomerular and tubular in ATL+LPS groups.LPS significantly increased the expression of TLR4,MyD88,p-I kappa B and p-p65(P<0.01),while ATL inhibited the expression of these proteins(P<0.01,P<0.05).There was no difference in the expression of p-p52 in each groups.(2)Conclusions:(1)ATL could inhibit the production of inflammatory factors and AKI biomarkers induced by LPS,reduce the levels of Scr and BUN,and protect renal function.(2)Both vivo and in vitro experiments showed that ATL could inhibit the expresssion of TLR4 and MyD88,p-IrκB and NF-κB classic pathway related protein expression of p-p65 induced by LPS.The effect anti-inflammatory and renoprotective of ATL is relate to the regulation of TLR4/MyD88/NF-B signaling pathway.