The Role Of EGFR Core Fucosylation On The Renal Interstitial Fibrosis

Objective:To study the effect of EGFR core fucosylation on renal fibrosis a nd the mechanism.Methods:Patients with primary glomerulonephritis and diagnosed with renal b iopsy were enrolled in the Nephropathy Department of first Affiliated Hospital of Da Lian Medical University from 2015.Cases would be removed with the diagno sis of secondary glomerular disease.Patients were divided into 4 groups,Norma l?Mild?Moderate and Severe.Control group were patients received surgery from Urology department.Renal pathological changes were observed by PAS staining,i nterstitial damage score were evaluated.The expression of FUT8 was tested by i mmunohistochemistry.And the relationship of FUT8 and renal interstitial damage were analyzed by Spearman correlation analysis.To verify the results above and futher explore the specific mechanism,we m ade animal experiments below.Fifty male wistar rats(180-220g)were randomly d ivided into ten groups.i.e,normal group,sham group(SHAM group,n = 5),Sham with GFP group(SHAM+GFP group,n=5),three days of unilateral ureteral obstruc tion(UUO3d group,n = 5),three days of unilateral ureteral obstruction and se ven days of release ureteral obstruction(RUUO 7d group,n = 5),three days o f unilateral ureteral obstruction and seven days of release ureteral obstruction wit h adenoviral-mediated knockdown of FUT8(RUUO 7d+FUT8Sh RNA group,n = 5),three days of unilateral ureteral obstruction and fourteen days of release urete ral obstruction(RUUO14d,n = 5),three days of unilateral ureteral obstruction a nd fourteen days of release ureteral obstruction with adenoviral-mediated knockdo wn of FUT8(RUUO 14d+FUT8Sh RNA group,n = 5),three days of unilateral ur eteral obstruction and twenty eight days of release ureteral obstruction(RUUO28d group,n = 5),three days of unilateral ureteral obstruction and twenty eight d ays of release ureteral obstruction with adenoviral-mediated knockdown of FUT8(RUUO 28d+FUT8Sh RNA group,n = 5).RUUO was induced by clamping the left ureter using a hemostatic ligating clip.we used PAS staining to observe re nal pathology under microscope.then we further detected and confirmed the ex pression changes of FUT8,?-SMA,E-cadherin,EGFR by RT-PCR?Western blot or immunohistochemistry.Results: There is no statistical significance for Five groups of patients in ag e,sex,blood cholesterol,blood calcium and phosphorus(P > 0.05);while for 24 h urine protein levels,increased serum creatinine,severe group is higher than o ther groups,and for blood urea nitrogen level,normal group is lower than other gr oups(P < 0.05).Spearman correlation analysis showed that FUT8 expression wa s positively correlated with renal interstitial fibrosis.Untreated obstructed rats sho wed marked tubular atrophy and apoptosis,tubulointerstitial macrophage infiltratio n.Following the relief of obstruction however,there was a significant restoration.Groups with with adenoviral-mediated knockdown of FUT8 showed reduced Fut8 expression which we observed through immunohistochemistry.As compared with n ormal groups,the protein levels of EGFR,and ?-SMA were significantly increase d in UUO rats detected by Western blot(P<0.05).They were significantly decrea sed after relief of UUO,and then gradually reduced to normal.Groups with wit h adenoviral-mediated knockdown of FUT8 reduced better.It was an opposite res ult of E-cadherin.Immunohistochemistry showed that the expression of ?-SMA sig nificantly increased in UUO group compared with normal group(P<0.05),whereas,t he expressions were obviously decreased after the release of ureter.Groups with with adenoviral-mediated knockdown of FUT8 reduced better It was an opposite result of E-cadherin.consistent results can be observed with RT-PCR and Wester n-Blot.The same trends were observed with ERK?JNK?p-ERK?p-JNK.For pERK and p-JNK groups with with adenoviral-mediated knockdown of FUT8 wer e lower than groups which release ureteral obstruction for the same time.While for ERK and JNK groups with with adenoviral-mediated knockdown of FUT8 an d groups which release ureteral obstruction for the same time showed no differen ce(P>0.05).Conclusion : The expression of FUT8 is positively related with renal interst itial fibrosis and renal tubular damage.Inhibition of FUT8 expression can inhibit EGFR/ERK/JNK pathway which lead to renal interstitial fibrosis.