hUSCs通过调控SPHK1/S1P通路对糖尿病大鼠肾缺血再灌注损伤的改善作用OA

Objective:To explore whether human urine-derived stem cells(hUSCs)can improve renal ischemia-reperfusion injury(RIRI)in diabetic rats by regulating sphingosine kinase 1(SPHK1)/sphingosine-1-phosphate(S1P)pathway.Methods:Sixty male SD rats were selected and randomly divided into control group(Con group),sham operation group(Sham group),RIRI group,SPHK1 inhibitor PF543 group(PF543 group),hUSCs group,hUSCs+SPHK1 activator PMA group(hUSCs+PMA group),with 10 rats in each group.Diabetic rat models were established in rats of all groups except the Con group.RIRI models were established in rats of all groups except the Con group and Sham group.Interventions were performed on rats of each group 30 minutes before model establish-ment.Rats in PF543 group were injected with 7 mg/kg PF543 via tail vein;rats in hUSCs group were injected with 50 μl PBS containing 5× 105 hUSCs via tail vein;rats in hUSCs+PMA group were injected with 50 μl PBS contai-ning 5×105 hUSCs and 200 μg/kg PMA via tail vein;rats in Con group,Sham group and RIRI group were injected with equal volume of 0.9％sodium chloride solution via tail vein.The serum levels of serum creatinine(SCr),blood urea nitrogen(BUN),cystatin C(Cys C),interleukin-1β(IL-1β),IL-6 and tumor necrosis factor-α(TNF-α),as well as urinary kidney injury molecule-1(KIM-1)and neutrophil gelatinase-associated lipocalin(NGAL)were detected.HE staining was used to observe renal histopathological changes.TUNEL staining was adopted to detect renal tissue cell apoptosis.Western blot was utilized to detect protein expressions of cleaved Caspase-3,SPHK1 and S1P in renal tissues.Results:Compared with the Con group,a small amount of inflammatory cell infiltration was observed in renal tissues of rats in the Sham group,and serum levels of IL-1β,TNF-α and IL-6 were increased(all P＜0.05).Com-pared with the Sham group,rats in the RIRI group presented typical characteristics of acute renal tubular injury in re-nal tissues;serum levels of BUN,SCr,Cys C,IL-1β,TNF-α,IL-6,urinary levels of KIM-1 and NGAL,renal his-topathological score,cell apoptosis rate,and protein expression levels of cleaved Caspase-3,SPHK1 and S1P were all increased(all P＜0.05).Compared with the RIRI group,renal pathological changes of rats in PF543 group and hUSCs group were significantly improved;serum levels of BUN,SCr,Cys C,IL-1β,TNF-α,IL-6,urinary levels of KIM-1 and NGAL,renal histopathological score,cell apoptosis rate,and protein expression levels of cleaved Caspase-3,SPHK1 and S1P were all decreased(all P＜0.05).There was no statistically significant difference in each index be-tween PF543 group and hUSCs group(all P＞0.05).PMA could reduce the improvement effect of hUSCs on RIRI in diabetic rats.Conclusion:hUSCs can reduce inflammatory response and cell apoptosis,alleviate renal tissue injury and improve renal function in diabetic rats with RIRI,and its mechanism of action may be related to the inhibition of SPHK1/S1P pathway.