| Background and Objective: There have been a lot of evidence that the development of diabetic kidney disease(DKD)is mainly attributed to renal mircrovascular abnormalities and chronic hypoxia,and closely related to inflammation.Our previous study has confirmed that angiopoietin-1(a primary member of angiopoietin)and L-mimosine(an inhibitor of hypoxia-inducible factor degradation)could relieve the diabetic kidney disease through improving the abnormal expression of angiogenesis-and hypoxia-relecated factors in diabetic kidney.But it is unclear whether these interventions affects the degree of inflammation and fibrosis of diabetic kidney.In this study,angiopoietin-1 and L-mimosine will be assessed for their effects on renal inflammation and fibrosis so as to enrich the nephroprotective evidence in diabetic kidney.Methods: Recombinant adenovirus vector expressing Ang-1(Ad-Ang-1)was constructed in our previous study.SD rat diabetic model was built by intraperitoneal injection with streptozotocin(STZ).The experimental rats were divided into six groups: normal control group(Group N),diabetic group(Group D),empty vector group(Group K,model rat was only treated with 3×108PFU adenovirus vector via a caudal vein injection at 8 week),Ang-1 treatment group(Group A,model rat was treated with 3×108PFU Ad-Ang-1 via a caudal penis vein injection at 8 week),L-mim treatment group(Group L,model rat was treated with 50mg/kg L-mim via intraperitoneal injection every other day at 8 week),and Ang-1 + L-mim treatment group(Group AL,model rat was treated with both Ad-Ang-1and L-mimosine with the former method).After 12 and 16 weeks,the samples of blood,urine,and renal tissue were collected.The blood glucose,serum urea,serum creatinine and24-hour urinary protein were observed.The renal pathological changes was observed by conventional HE,PAS and Masson staining,levels of transforming growth factor-?1(TGF-?1),fibronectin(FN),?-smooth muscle actin(?-SMA),monocyte chemotacticprotein 1(MCP-1),and ED-1 were evaluated by immunohistochemistry.The correlation analysis between indicators were also observed.Results: 1.The blood glucose and 24 h urine protein: The levels of blood glucose and 24 h urine protein in five diabetic model groups were significantly higher than that of Group N(P<0.05),and 24 h urine protein level in Groups L and AL was significantly lower than that of Groups D and A(P<0.05).2.Serum creatinine and urea: The serum creatinine and urea levels in five diabetic model groups were upregulated at different degrees as compared with Group N.Their levels between three interventional groups were no difference(P > 0.05).Compared with Group D,the increased creatinine was no difference(P>0.05),but the increased urea at 12 week was higher(P<0.05)in three interventional groups.3.Renal pathology: The glomerular size,mesangial matrix,and collagen hyperplasia were increased with dilatation of partial tubular and Bowman's capsule,tubulointerstitial inflammatory cell infiltration in the five diabetic model groups,but their changes in three drug intervention groups were relatively reduced.4.The results displayed by immunohistochemistry:(1)TGF-?1 was mainly expressed in renal tubular epithelial cell,FN was mainly expressed in basement membrane and tubulointerstitial area,?-SMA was mainly expressed in small vascular smooth muscle cell cytoplasm,MCP-1 was mainly expressed in renal tubular epithelial cell,ED-1 was mainly expressed in tubulointerstitial area.(2)The expression of TGF-?1,FN and ?-SMA in renal tissue of five diabetic model groups were significantly up-regulated as compared with Group N(P < 0.05).Levels of TGF-?1 and FN in the three drug interventional groups were significantly lower than that of Group D(P<0.05),while their levels in Group AL were lower than that of gGroups A and L(P < 0.05).The level of?-SMA in Group AL was significantly lower than that of Groups D and L(P<0.05).(3)The expression of MCP-1 and ED-1 in renal tissue of five diabetic model groups(except Group AL at 12 week)were up-regulated as compared with Group N(P<0.05),and level of ED-1 in the three drug interventional groups was significantly lower than that of Group D(P<0.01),while its level in Group AL was lower than that of Groups A and L(P<0.01).The level of MCP-1 in Group AL was significantly lower than that of Groups D and L(P<0.05),and Group A at 16 week(P<0.01).5.The correlation analysis: The levels of TGF-?1,FN and ?-SMA were positively correlated with the levels of MCP-1 and ED-1(r=0.839,r=0.898,P < 0.01;r=0.846,r=0.875,P<0.01;r=0.783,r=0.794,P<0.01),respectively.The level of 24 h urine protein was also positively correlated with the levels of MCP-1,ED-1,TGF-?1,and FN(r=0.538,P<0.01;r=0.570,P<0.01;r=0.407,P<0.01;r=0.326,P<0.05),respectively.Conclusion:1.Angiopoietin-1 and L-mimosine can alleviate renal inflammation and fibrosis in type 1 diabetic rats.2.Angiopoietin-1 combined with L-mimosine may be superior to single use on improving renal inflammation and fibrosis in type 1 diabetic rats. |
PDF Full Text Request