Study Of Autophagy In The Pathogenesis Of Systemic Juvenile Idiopathic Arthritis And The Effect Of Vitamin D

Objective:Western blotting was used to detect the expression of autophagic protein in peripheral blood lymphocyte of children with sJIA.Enzyme-linked immunosorbent assay(ELISA)was used to detect the level of 25(OH)D in peripheral blood of children with sJIA.The role of autophagy and 25(OH)D in the pathogenesis of sJIA was explored in combination with the results of clinical laboratory examination in children with sJIA,which provided a theoretical basis for the precise treatment of sJIA.Methods:From January 2017 to December 2018,15 children with newly diagnosed sJIA were admitted to the pediatric outpatient department and in-patient department of the Second Hospital of Hebei Medical University.At the same time,20 healthy children in the outpatient department of growth and development in our hospital served as the control group.Serum 25(OH)D level(ng/ml)was detected by ELISA,lymphocyte LC3 and P62 expression was detected by Western blotting,and related laboratory indicators were recorded in detail.To analyze the level of serum 25(OH)D and the expression of autophagy protein in children with sJIA before and after vitamin D treatment,and to explore the role of 25(OH)D in the pathogenesis of sJIA and its influence on autophagy level.Results:1.Changes of related laboratory indicators in children with sJIA before and after treatmentWBC,NEUT%,PLT,CRP,ESR,SF and IgG in sJIA group were significantly lower than those before treatment,and HGB was significantly higher than those before treatment,with statistical significance(P < 0.05).2.The expression of autophagic protein in peripheral blood lymphocyte of children with sJIA and the relationship between autophagic protein and autophagic protein.1)Compared with healthy children,the expression of LC3-II protein in peripheral blood lymphocyte of newly treated sJIA group was significantly increased(t=8.242,P<0.05);the expression of P62 protein in peripheral blood lymphocyte of newly treated sJIA group was significantly lower than that of healthy children(t=-10.681,P<0.05).2)Compared with healthy children,the expression of LC3-II protein in peripheral blood lymphocyte in sJIA treatment group was increased with statistical significance(t=3.937,P<0.05);the expression of P62 protein in peripheral blood lymphocyte in vitamin D treatment group was decreased with statistical significance(t=-4.613,P<0.05).3)Compared with sJIA group,the expression of LC3-II protein in sJIA group decreased significantly(t =3.979,P<0.05);compared with sJIA group,the expression of P62 protein in peripheral blood lymphocyte decreased significantly(t=-6.087,P<0.05).4)Immunofluorescence staining showed that the expression of LC3-II in lymphocyte cytoplasm was stronger than that of normal control group,which was consistent with Western blotting results.5)There was a negative correlation between the scatter plots of LC3-II and P62 integral optical density of peripheral blood lymphocytes in children with sJIA,and it was statistically significant(Pearson correlation coefficient-0.864,P<0.05).3.Serum 25(OH)D levels in children with sJIA1)The level of 25(OH)D in the initially treated sJIA group was significantly lower than that in the healthy children,which was statistically significant(t=-4.776 P<0.05)[(6.494�2.051)ng/ml vs(13.091�5.030)ng/ml].2)25(OH)D levels increased in the vitamin D treatment group compared with the initial sJIA group,with statistical significance(t=-2.568 P<0.05)[(8.795�2.799)ng/ml vs(6.494�2.051)ng/ml].3)25(OH)D levels were still lower in the vitamin D treatment group compared with the healthy children,which was not statistically significant(t=-2.973 P=0.05)[(8.795�2.799)ng/ml vs(13.091�5.030)ng/ml].Conclusions:1.The level of autophagy in children with sJIA is higher than that in healthy children.It is speculated that overexpression of autophagy may be involved in the pathogenesis of sJIA.2.Vitamin D level is deficient or insufficient in children with sJIA.Low level of vitamin D is related to the occurrence of sJIA.It is speculated that vitamin D supplementation may contribute to the recovery of the disease.3.The level of autophagy decreased after vitamin D supplementation in children with sJIA.It is speculated that vitamin D may play a regulatory role in the process of autophagy.