The Role Of Relaxin In Henoch-schonlein Purpura In Children

ObjectiveTo investigate the expression of RLX in blood and renal tissue of patients withHSP, and its correlation with clinical indexes and pathological changes, and exploreits effect on the pathogenesis of HSP/HSPN, and explore the relationship betweenRLX and TNF-α, ET-1.MethodsAccording to the clinical urine manifestation,39patients with henoch-schonleinpurpura(HSP) were divided into non-kidney damage group(n=20) and kidney damagegroup(n=19). All39patients collected blood samples from the acute and convalescentphase.19patients from kidney damage group were divided into mild lesions(n=5),moderate lesions(n=9) and severe lesions(n=5), according to the degree ofpathological changes.RLX and ET-1concentrations were detected with enzyme-labeled immunosorbent assay(ELISA) method.TNF-α concentration was detectedwith Chemiluminescence immunoassay method. RLX, TNF-α and ET-1proteinexpressions in renal tissues were detected with immunohistochemistry method.ResultsIn the acute phase, the serum levels of RLX,TNF-α,ET-1in HSP weresignificantly higher than normal control, and their concentrations were significantlyhigher in kidney damage group than in non-kidney damage group(P<0.05).Compared with acute phase, the serum levels of RLX,TNF-α,ET-1in HSP in theconvalescent phase were significantly lower, and the levels of decline were slower inkidney damage group than in non-kidney damage(P<0.05).Weak expressions ofRLX,TNF-α and ET-1in renal tissues were found in normal control, while theexpressions of RLX,TNF-α and ET-1in renal tissues significantly increased inHSPN(P<0.05),with the pathological changes of renal tissue aggravating.Andpositive correlations were found between the expression of RLX and TNF-α,ET-1inserum and renal tissue as well(P<0.001). The expression of RLX in renal tissues wassignificantly correlated with the total urine protein for24hour (P<0.01) and the serum level of RLX(P<0.001).Conclusions(1) There were a modest up-regulation in serum and renal RLX proteinexpression in HSP, and the severity of the disease was closely related with RLXlevels, it may be an important mechanism that upregulation of RLX may play adefensive role in delaying disease progression of HSP/HSPN; and the level of RLX inserum had a positive correlation with the expression of RLX in renal tissue, itsuggested that the detection of serum RLX level can assess the severity of renal injuryindirectly.(2) RLX expression levels had positive correlations with TNF-α and ET-1expression levels in serum and renal tissue in HSP, it suggested that TNF-α andET-1may be involved in promoting the upregulation of RLX protein expression.