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Objective To investigate the effect and mechanism of renal fibrosis after macrophage depletion in C3 - deficient unilateral ureteral obstruction mice. Methods Renal interstitial fibrosis model was established by unilateral ureteral obstruction (UUO) in male C3-deficient mice and age-matched C57BL/6 WT mice (8-12 weeks of age). Mice were randomly divided into 4 groups, including sham operation in wild type group(WT/sham)(n=18), UUO operation in wild type group(WT/UUO)(n=18), sham operation in C3-deficient group(C3KO/sham)(n=18), and UUO operation in C3-deficient group(C3KO/UUO)(n=18). The expression of complement C3 was detected by immunohistochemical staining and renal interstitial macrophages were assessed by immunofluorescence staining. Tubulointerstitial fibrosis was observed by both HE staining and Masson staining after 14 days of UUO. Collagen accumulation and score of tubulointerstitial injury were obtained. Wild type and C3-deficient UUO mice were treated by liposome clodronate in early or late stage respectively and then interstitially infiltrated macrophages and renal fibrosis were analysed. Mice were sacrificed randomly at 3,7,14 days after UUO and obstructed kidneys were collected. Macrophage phenotype was detected by double-labeling immunofluorescence with F4/80 and iNOS for the M1, F4/80 and CD206 for the M2 macrophage subpopulation. iNOS, Arg-1 and CD206 were also detected by western blot. Results C3 deficient mice exhibited attenuated renal fibrosis, reduced collagen accumulation and tubulointerstitial injury score compared with WT mice (P<0.01). Meanwhile, macrophage depletion in early or late stage of UUO reduced renal fibrosis in WT mice, but had no effect on C3-deficient UUO mice. Decreased accumulation of M1 macrophages and expression of iNOS, increased accumulation of M2 macrophages and expression of Arg-1, CD206 were found in C3 deficient mice compared with WT mice in early stage of UUO (P<0.01). Conclusion Renal fibrosis is not reduced after depletion of macrophages in C3 deficient UUO mice due to the altered macrophage polarization.
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Objective@#To investigate the effect and mechanism of renal fibrosis after macrophage depletion in C3-deficient unilateral ureteral obstruction mice.@*Methods@#Renal interstitial fibrosis model was established by unilateral ureteral obstruction (UUO) in male C3-deficient mice and age-matched C57BL/6 WT mice (8-12 weeks of age). Mice were randomly divided into 4 groups, including sham operation in wild type group (WT/sham) (n=18), UUO operation in wild type group (WT/UUO) (n=18), sham operation in C3-deficient group (C3KO/sham) (n=18), and UUO operation in C3-deficient group (C3KO/UUO) (n=18). The expression of complement C3 was detected by immunohistochemical staining and renal interstitial macrophages were assessed by immunofluorescence staining. Tubulointerstitial fibrosis was observed by both HE staining and Masson staining after 14 days of UUO. Collagen accumulation and score of tubulointerstitial injury were obtained. Wild type and C3-deficient UUO mice were treated by liposome clodronate in early or late stage respectively and then interstitially infiltrated macrophages and renal fibrosis were analysed. Mice were sacrificed randomly at 3,7,14 days after UUO and obstructed kidneys were collected. Macrophage phenotype was detected by double-labeling immunofluorescence with F4/80 and iNOS for the M1, F4/80 and CD206 for the M2 macrophage subpopulation. iNOS, Arg-1 and CD206 were also detected by western blot.@*Results@#C3 deficient mice exhibited attenuated renal fibrosis, reduced collagen accumulation and tubulointerstitial injury score compared with WT mice (P<0.01). Meanwhile, macrophage depletion in early or late stage of UUO reduced renal fibrosis in WT mice, but had no effect on C3-deficient UUO mice. Decreased accumulation of M1 macrophages and expression of iNOS, increased accumulation of M2 macrophages and expression of Arg-1, CD206 were found in C3 deficient mice compared with WT mice in early stage of UUO (P<0.01).@*Conclusion@#Renal fibrosis is not reduced after depletion of macrophages in C3 deficient UUO mice due to the altered macrophage polarization.
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Objective To investigate the effect of complement C3a on mouse podocytes phenotype transformation.Methods Purified C3a recombinant protein was used to stimulate mature mouse podocytes.The expression of the mature podocyte markers synaptopodin,podocin,nephrin,CD2-associated protein (CD2AP) and the mesenchymal cell markers fibroblast specific protein 1 (FSP-1),α-smooth muscle actin (α-SMA) were detected by RT-PCR,Western blotting,immunochemistry and immunofluorescence,respectively.Some podocytes were transfected with integrin-linked kinase (ILK) siRNA before the administration of C3a,the expression of nephrin and α-SMA were accessed by Western blotting,and the expression of Snail and α-actinin 4 were accessed by Western blotting and immunochemical method.The migration ability of podocytes was observed by scratch test.Results Immunocytochemistry and immunofluorescence analysis showed that synaptopodin,podocin,nephrin,CD2AP were highly expressed by mature mouse podocytes.The expression of these podocyte markers could be markedly inhibited after 24 h of C3a (0.1 μmol/L) treatment,and accompanied by the induction of mesenchymal markers FSP-1 and α-SMA.Compared with control group,the mRNA levels of synaptopodin,podocin,CD2AP and nephrin were significantly repressed by the administration of C3a in a dose-dependent manner,whereas the transcription of FSP-1 and α-SMA were remarkably up-regulated by C3a treatment (P ＜ 0.05,respectively).Western blotting analysis also confirmed the decrease of synaptopodin,podocin,nephrin and CD2AP protein and the increase of FSP-1 and α-SMA protein were closely depend on the C3a concentration (P ＜ 0.05,respectively).To further assess the downstream of C3a,some podocytes were transfected with ILK siRNA before the administration of C3a.Compared with C3a group,the protein levels of nephrin and α-SMA were significantly changed by the administration of ILK siRNA (P ＜ 0.05,respectively).The expression of α-actinin 4 and Snail induced by C3a were inhibited by ILK knockdown (P ＜ 0.05,respectively),accompanied by a decline of cell migration potency.Conclusion Complement fragment C3a can induce transformation of mouse podocytes to mesenehymal cells,and ILK signaling pathway is involved in this cell type transformation.
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Objective To follow up the long-term prognosis of acute kidney injury (AKI) patients with normal basic renal function,and to further identify the clinical features as well as risk factors associated with the prognosis of AKI patients.Methods Clinical date of 166 patients who occurred AKI episode during hospitalization from Jan 1 2011 to Dec 31 2014 in The First Affiliated Hospital of Fujian Medical University were retrospectively analyzed.All these patients had normal basic renal function and had follow-up of more than two years after discharge.According to their renal function after two years,patients were divided into recover and non-recover group.The clinical features and risk factors associated with the prognosis of AKI patients were identified using multivariate logistic regression,and the proportion of renal function progression was calculated during follow-up period.Results One hundred and sixty-six patients were enrolled in this observational study,including 114 male,52 female with an average age of 58.1± 16.6.Eighty-seven patients were AKI stage 1,39 AKI stage 2,and 40 AKI stage 3.Thirty-seven patients were caused by pre-renal factors,113 patients by renal causes and 16 patients by post-renal causes.Renal function when discharged (P=0.002,OR=2.980) and infection (P=0.003,OR=2.786) were the risk factors of failing to restore after two years.Eighty-four patients' renal function returned to normal when discharged,but the number of patients whose renal function progressed to CKD 3 stage and even worse 1 year and two years later were 12 (14.3％) and 20 (23.8％) respectively.Fifty-four patients were diagnosed as partial recovery and 28 patients as non-recovery when discharged.One year later 22 (40.7％) and 12 (42.9％) patients' renal function progressed to CKD 3 stage and more,while those numbers became 28 (51.9％) and 16 (57.1％) two years later.Conclusions The risk factors of AKI long-term outcome include unrecovered renal function when discharged and infection.After AKI episode,even with fully recovered renal function,patients are still possible to progress to CKD,highlighting the importance of follow-up observation.
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Objective To observe the effects of bone marrow?derived mesenchymal stem cells (BMSC) on glomerular podocyte injured by lipopolysaccharide (LPS) and the expression of related protein. Methods Podocytes are divided into control group, BMSC group, LPS group and LPS plus BMSC group. After 24 hours of intervention, observing each experimental group podocyte form under inverted phase contrast microscope;detecting the expressions of mRNA and protein of nephrin, CD2AP, synaptopodin, and TRPC6 by RT?PCR and Western?blot. Results Compared with control group, expressions of nephrin, CD2AP, and synaptopodin in LPS group decreased (P<0.05) while that of TRPC6 increased (P<0.05); compared with LPS group, expressions of nephrin, CD2AP, and synaptopodin in LPS+MSC group increased (P<0.05) while that of TRPC6 decreased (P<0.05). Conclusion BMSC may relieve LPS?induced podocyte injury.
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Objective To investigate the effects of erythropoietin(EPO)on the function of glomerular endothelial cells in rats with chronic renal failure(CRF). Methods The CRF model was established by a two stage 5/6 nephrectomy procedure in rats.Experimental rats were randomly divided into four groups:sham operation group (control group),CRF group,CRF rats treated with 30 U/kg EPO(low-dosage group)and with 50 U/kg EPO (high-dosage group).CRF rats received EPO by hypodermic injection for 6 weeks and then were sacrificed.Serum creatinine(Scr),blood urea nitrogen fBUN),urine protein,haematoglobin (Hb) and blood pressure were measured.The renal morphologie changes were evaluated on periodic acid-schiff (PAS) stained sections.The CD34 and CD31 expressions in glomerulus were detected by immunohistochemistry method.The mRNA of endothelin 1(ET-1),endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor (VEGF) were detected by RT-PCR. Results The expressions of CD34 and CD31 protein in glomerulus,and the expressions of eNOS and VEGF roRNA in renal tissue were higher in EPO treatment group than those in CRF model group(all P<0,05).The expression of ET-1 mRNA in renal tissue was lower in EPO treatment group than that in CRF model group.In addition,the Scr,BUN,urine protein and blood pressure in EPO treatment group were significantly lower than those in CRF model group (all P<0.05).Haematoglobin in EPO treatment group was higher than that in CRF model group (P<0.05).Reanl pathological injury wss improved by EPO treatment in dose-dependent manner. Conclusion EPO can ameliorate renal pathological injury and renal function in rats with chronic renal failure,maybe through promoting the renovation of glomerular capillary endothelium and improving the function of glomerular endothelial cells.
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Objective To investigate the effects of erythropoietin (EPO) on the number and function of peripheral blood endothelial progenitor cells (EPCs) from rats with chronic renal failure (CRF). Methods The model of chronic renal failure was established by a two-stage 5/6nephrectomy procedure in rats. Experimental rats were randomly divided into four groups (n =7,respectively): sham operation group, CRF group, CRF rats treated with 30 U/kg EPO (low-dosage group) and with 50 U/kg EPO (high-dosage group). CRF rats were given EPO by hypodermic injection for 6 weeks, then EPCs were isolated by density gradient centrifugation from peripheral blood mononuclear cells. The ability of cell proliferation, adhesion and vasculogenesis in vitro was further observed. Results Compared to sham operation group, the ability of cell proliferation,adhesion and vasculogenesis in vitro in CRF rats was remarkably decreased (P＜0.05, respectively).Such ability was promoted significantly in dose-dependent manner by EPO treatment (P＜0.05,respectively). Conclusion EPO can improve the number and ability of endothelial progenitor cells from rats with chronic renal failure.
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Objective To investigate the differentiation of rat bone marrow mesenchymal stem cells (MSCs) to renal tubular epithelial-like cells under different conditions. Methods MSCs were obtained from rat marrow. MSCs were isolated by gradient density centrifugation and plastic adherence and then purified. Surface markers were identified with flow cytometry after amplification in vitro. The purified MSCs of the third passage were cultured respectively as follows: (1) control group: DMEM medium with fetal bovine serum(FBS). (2) all-trans retinoic acid (ATRA) group: DMEM medium with FBS, ATRA and ischemic reperfusion-injured kidney tissue homogenate. (3)combination group: DMEM medium with FBS, ATRA, ischemic reperfusion-injured kidney tissue homogenate, epidermal growth factor (EGF) and bone morphogenetic protein 7 (BMP-7). After 7 days, the MSCs were collected for alkaline phosphatase (AKP) staining, cytokeratin-18 and E-cadherin immunocytochemical analysis. Results The positive rates of the third passage MSCs in CD44, CD90 and CD29 were 97.8%±0.9%, 96.8%±1.4% and 97.6%±2.4%,respectively, but in CD11b/c and CD34 were only 13.2%±0.6% and 1.2%±0.5%. The MSCs in control group were spindle. The MSCs in ATRA group were round and elliptic. The MSCs in combination group became cobblestone-like cells after 7 days. AKP staining showed that tubular epithelial-like cells from MSCs in control group were negative, some above cells in ATRA group were positive and number of above cells increased in combination group. Compared with negative control group, the ratios of cytokeratin-18 positive cells in ATRA group and combination group were respectively increassed by 29.47%±1.08% and 47.52%±2.13% (all P<0.05), the ratios of E-cadherin positive cells in ATRA group and combination group were respectively increased by 14.88%±2.46% and 36.15%±1.13% (all P<0.05). Conclusion MSCs may differentiate by renal tubular epithelial-like cells under the induction of ischemic reperfusion-injured kidney tissue homogenate and ATRA in vitro, which are further differentiated under the combined induction of EGF and BMP-7.