OBJECTIVETo investigate the effect of losartan on the expression of monocyte chemoattractant protein-1 (MCP1) and transforming growth factor-β(1) (TGF-β(1)) in the kidney of rats with unilateral urethral obstruction (UUO) and evaluate protective effect of losartan against reanal interstitial fibrosis.

METHODSRat models of UUO were treated with losartan at the routine dose, high dose, and very high dose (50, 200, and 500 mg/kg daily, respectively), and saline was given to UUO model rats and rats with sham operation. At 7, 14, and 21 days, the tail cuff blood pressure (TCP), 24-h urine protein (Upro), serum Scr, BUN, K(+), percentage of renal damage and renal interstitial fibrosis (%INT) were measured in the rats. MCP1 protein in the renal tissues was detected using immunohistochemistry, and MCP1 and TGF-β(1) mRNA expressions were assayed using RT-PCR.

RESULTSAs the UUO prolonged, Upro, TCP, tubular damage, %INT, and MCP1 and TGF-β(1) mRNA expressions all increased significantly (P<0.05). High and very high doses of losartan, compared with the routine dose, obviously reversed these changes.

CONCLUSIONHigh-dose losartan can effectively control blood pressure, reduce renal damage and fibrosis, and inhibit MCP1 and TGF-β(1) expression in rats with UUO, and at a very high dose, losartan can more effectively reduce 24-h Upro than the high-dose group. High and very high doses of losartan offer better protective effect on the kidney in rats with UUO.

Animals ; Chemokine CCL2 ; metabolism ; Fibrosis ; etiology ; prevention & control ; Kidney ; metabolism ; pathology ; Losartan ; pharmacology ; Male ; Rats ; Rats, Sprague-Dawley ; Transforming Growth Factor beta1 ; metabolism ; Ureteral Obstruction ; complications ; drug therapy

OBJECTIVETo investigate the role of integrin-linked kinase (ILK) on renal tubular epithelial-mesenchymal transition and the regulatory effect of urokinase on LIK expression in mice with obstructive nephropathy.

METHODSNormal male mice were randomly divided into sham-operated group (n=20), unilateral ureteral obstruction (UUO) group (n=28), and UUO with urokinase treatment group (uPA, n=28), and UUO was induced surgically in the latter two groups. The mice were sacrificed on days l, 3, 7 and 14 after the surgery, and renal interstitial fibrosis (RIF) was graded according to the result of Masson staining. The expression of ILK in the renal tissues of the rats was examined by immunofluorescence staining and Western blotting, and the expression of E-cadherin was detected by immunohistochemistry. RT-PCR was used to examine the mRNA expressions of ILK, E-cadherin and alpha-smooth muscle actin (alpha-SMA).

RESULTSThe expressions of ILK mRNA and protein were significantly increased in UUO group, but significantly decreased by treatment with uPA (P<0.05). The expression of alpha-SMA mRNA level was significantly increased, while E-cadherin decreased in mice with UUO on day 3 after the surgery. Treatment with uPA significantly inhibited such effects (P<0.05).

CONCLUSIONILK plays an important role in renal interstitial fibrosis by mediating epithelial-mesenchymal transition. Urokinase attenuates renal tubulointerstitial fibrosis in mice with UUO possibly by inhibiting ILK expression and preventing tubular epithelial-mesenchymal transition.

Animals ; Cell Transdifferentiation ; drug effects ; Epithelial Cells ; metabolism ; pathology ; Fibrosis ; Kidney Tubules ; metabolism ; pathology ; Male ; Mesoderm ; pathology ; Mice ; Protein-Serine-Threonine Kinases ; genetics ; metabolism ; physiology ; Ureteral Obstruction ; genetics ; metabolism ; pathology ; Urokinase-Type Plasminogen Activator ; pharmacology

OBJECTIVES: To explore the mechanism of transforming growth factor-β1 (TGF-β1) induce renal fibrosis. METHODS: Renal fibroblast NRK-49F cells treated with and without TGF-β1 were subjected to RNA-seq analysis. DESeq2 was used for analysis. Differentially expressed genes were screened with the criteria of false discovery rate<0.05 and l o g 2 F C >1. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed for differentially expressed genes. Genes encoding transcription factors were further screened for differential expression genes. Then, the expression of these genes during renal fibrosis was verified using unilateral ureteral obstruction (UUO)-induced mouse renal fibrosis model and a public gene expression dataset (GSE104954). RESULTS: After TGF-β1 treatment for 6, 12 and 24 h, 552, 1209 and 1028 differentially expressed genes were identified, respectively. GO analysis indicated that these genes were significantly enriched in development, cell death, and cell migration. KEGG pathway analysis showed that in the early stage of TGF-β1 induction (TGF-β1 treatment for 6 h), the changes in Hippo, TGF-β and Wnt signaling pathways were observed, while in the late stage of TGF-β1 induction (TGF-β1 treatment for 24 h), the changes of extracellular matrix-receptor interaction, focal adhesion and adherens junction were mainly enriched. Among the 291 up-regulated differentially expressed genes treated with TGF-β1 for 6 h, 13 genes (Snai1, Irf8, Bhlhe40, Junb, Arid5a, Vdr, Lef1, Ahr, Foxo1, Myc, Tcf7, Foxc2, Glis1) encoded transcription factors. Validation in a cell model showed that TGF-β1 induced expression of 9 transcription factors (encoded by Snai1, Irf8, Bhlhe40, Junb, Arid5a, Vdr, Lef1, Myc, Tcf7), while the expression levels of the other 4 genes did not significantly change after TGF-β1 treatment. Validation results in UUO-induced mouse renal fibrosis model showed that Snai1, Irf8, Bhlhe40, Junb, Arid5a, Myc and Tcf7 were up-regulated after UUO, Vdr was down-regulated and there was no significant change in Lef1. Validation based on the GSE104954 dataset showed that IRF8 was significantly overexpressed in the renal tubulointerstitium of patients with diabetic nephropathy or IgA nephropathy, MYC was highly expressed in diabetic nephropathy, and the expressions of the other 7 genes were not significantly different compared with the control group. CONCLUSIONS TGF-β1 induces differentially expressed genes in renal fibroblasts, among which Irf8 and Myc were identified as potential targets of chronic kidney disease and renal fibrosis.
Mice ; Animals ; Humans ; Transforming Growth Factor beta1/metabolism* ; Diabetic Nephropathies/pathology* ; Transcriptome ; Signal Transduction ; Kidney ; Ureteral Obstruction/pathology* ; Fibrosis ; Interferon Regulatory Factors ; Transforming Growth Factor beta/metabolism* ; DNA-Binding Proteins/metabolism* ; Transcription Factors/metabolism*

BACKGROUNDSrc homology 2 domain-containing protein tyrosine phosphatase-2 (SHP-2) is a kind of intracellular protein tyrosine phosphatase. Studies have revealed its roles in various disease, however, whether SHP-2 involves in renal fibrosis remains unclear. The aim of this study was to explore the roles of myeloid cells SHP-2 in renal interstitial fibrosis.

METHODSMyeloid cells SHP-2 gene was conditionally knocked-out (CKO) in mice using loxP-Cre system, and renal interstitial fibrosis was induced by unilateral ureter obstruction (UUO). The total collagen deposition in the renal interstitium was assessed using picrosirius red stain. F4/80 immunostaing was used to evaluate macrophage infiltration in renal tubular interstitium. Quantitative real-time polymerase chain reaction and enzyme linked immunosorbent assay were used to analyze the production of cytokines in the kidney. Transferase-mediated dUTP nick-end labeling stain was used to assess the apoptotic renal tubular epithelial cells.

RESULTSSrc homology 2 domain-containing protein tyrosine phosphatase-2 gene CKO in myeloid cells significantly reduced collagen deposition in the renal interstitium after UUO. Macrophage infiltration was evidently decreased in renal tubular interstitium of SHP-2 CKO mice. Meanwhile, the production of pro-inflammatory cytokines was significantly suppressed in SHP-2 CKO mice. However, no significant difference was observed in the number of apoptotic renal tubular epithelial cells between wild-type and SHP-2 CKO mice.

CONCLUSIONSOur observations suggested that SHP-2 in myeloid cells plays a pivotal role in the pathogenesis of renal fibrosis, and that silencing of SHP-2 gene in myeloid cells may protect renal from inflammatory damage and prevent renal fibrosis after renal injury.

Animals ; Enzyme-Linked Immunosorbent Assay ; Female ; Fibrosis ; enzymology ; pathology ; Immunohistochemistry ; Kidney Diseases ; enzymology ; pathology ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Myeloid Cells ; metabolism ; Protein Tyrosine Phosphatase, Non-Receptor Type 11 ; genetics ; metabolism ; Ureteral Obstruction ; enzymology ; pathology

OBJECTIVETo explore the protective effects of bicyclol against renal interstitial fibrosis and possible mechanisms of the protection.

METHODSEighty-one Sprague-Dawley (SD) rats were randomly assigned to a sham-operated group and UUO groups with and without bicyclol treatment. A rat model of renal interstitial fibrosis was prepared by unilateral ureteral obstruction (UUO). Renal tissues were examined by hematoxylin & eosin and Masson staining on 7, 14 and 21 days. Immunhistochemistry was used for determining plasminogen activator inhibitor-1(PAI-1) expression in the renal interstitium. PAI-1 mRNA expression in renal tissues was semi-quantitatively determined by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTSThe relative areas of renal interstitial fibrosis in the bicyclol-treated UUO group 7, 14 and 21 days after operation were (9.6 ± 0.6)%, (16.8 ± 0.8)% and (33.6 ± 1.6)% respectively, which were significantly lower than those in the untreated UUO group [13.0 ± 0.7)%, (25.8 ± 1.5)% and (53.2 ± 2.5)% respectively] (P<0.05). The levels of protein and mRNA expression of PAI-1 in the bicyclol-treated UUO group decreased significantly compared with those in the untreated UUO group 7, 14 and 21 days after operation (P<0.05).

CONCLUSIONSBicyclol can alleviate renal interstitial injury and renal interstitial fibrosis caused by UUO in rats, possibly through a downregulation of renal PAI-1 expression.

Animals ; Biphenyl Compounds ; pharmacology ; therapeutic use ; Fibrosis ; Kidney ; chemistry ; drug effects ; metabolism ; pathology ; Male ; Plasminogen Activator Inhibitor 1 ; analysis ; genetics ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Ureteral Obstruction ; drug therapy ; metabolism ; pathology

OBJECTIVETo study the effect of Astragalus mongholicus (AM) on the expression of transforming growth factor-beta1 (TGF-beta1) in SD rats with unilateral ureteral occlusion (UUO) and to elucidate the mechanisms underlying the renoprotective effects of AM.

METHODFifty-four Sprague-Dawley rats were randomly divided into 4 groups: sham-operation group, the UUO group and AM treatment group. After administration of AM (10 g kg(-1) d(-1)) for 3, 7 and 14 days, the dynamic histological changes of renal interstitial tissues were observed and renal damage including tubular impairment and interstitial fibrosis were quantified on HE and Masson stained tissue sections. The expression of TGF-beta1 and alpha-smooth muscle actin (alpha-SMA) was measured by immunohistochemistry staining sections. The mRNA of TGF-beta1 and alpha-SMA were reverse transcribed and quantified by real-time PCR. The expression of TGF-beta1 protein were assessed by Western blot.

RESULTRenal damage was exacerbated and the expression of alpha-SMA and TGF-beta1 were all significantly increased in UUO group compared with those of sham-operation group (P<0.05) at each time point. Tubular impairment and interstitial fibrosis were alleviated, and up-regulations of expressions of TGF-beta1 and alpha-SMA were significantly suppressed by AM treatment (P<0.05).

CONCLUSIONAM can ameliorate renal interstitial fibrosis induced by UUO in vivo. The mechanisms of its antifibrotic effects might be related with the down-regulation of TGF-beta1 expression and suppression of tubular epithelial myofibroblast transdifferentiation in the progress of renal interstitial fibrosis.

Actins ; genetics ; Animals ; Astragalus Plant ; chemistry ; Drugs, Chinese Herbal ; pharmacology ; Gene Expression Regulation ; drug effects ; Kidney Tubules ; drug effects ; metabolism ; Male ; RNA, Messenger ; genetics ; metabolism ; Rats ; Transforming Growth Factor beta1 ; genetics ; Ureteral Obstruction ; metabolism ; pathology ; prevention & control

OBJECTIVETo study the effects of astaxanthin on renal fibrosis and apoptosis induced by partial unilateral ureteral obstruction (UUO) in rats.

METHODSNinety-six male adult SD rats were randomized into 6 equal groups, namely the blank control group, sham-operated group, UUO group, and astaxanthin group at high, medium, and low doses. Left ureteral ligation was performed in UUO and astaxanthin groups, and two days before the operation, the rats in astaxanthin groups were lavaged with 25, 50, or 100 mg/kg astaxanthin daily for 14 days, while the same volume of saline was given to rats in UUO group and sham-operated group. Renal pathological in the rats was observed with HE staining, and the expression levels of TGF-β1, SGK1, and CTGF in the left kidney were detected immunohistochemically; the expression level of Bcl-2 and Bax were detected using Bcl-2 and Bax detection kits.

RESULTSCompared to UUO group, high- and medium-dose astaxanthin groups showed obviously ameliorated renal pathologies and reduced expressions of TGF-β1, SGK1, and CTGF in the left kidney with lessened renal cell apoptosis.

CONCLUSIONAstaxanthin can reduce UUO-induced renal fibrosis and renal cell apoptosis, demonstrating the renoprotective effect of astaxanthin against renal fibrosis.

Animals ; Apoptosis ; drug effects ; Connective Tissue Growth Factor ; metabolism ; Fibrosis ; Immediate-Early Proteins ; metabolism ; Kidney ; drug effects ; metabolism ; pathology ; Kidney Diseases ; metabolism ; pathology ; Male ; Protein-Serine-Threonine Kinases ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rats ; Rats, Sprague-Dawley ; Transforming Growth Factor beta1 ; metabolism ; Ureteral Obstruction ; metabolism ; pathology ; Xanthophylls ; pharmacology ; bcl-2-Associated X Protein ; metabolism

OBJECTIVETo investigate the expression of integrin-linked kinase (ILK) in kidneys of mice with unilateral ureteral obstruction and its relevance with the epithelial-mesenchymal transition.

METHODSMice were randomly divided into two groups, sham operation (C, n = 20) and unilateral ureteral obstruction (UUO, n = 40). The animals were sacrificed at day 1, 3, 7 and 14 respectively after the surgery. Tubulointerstitial fibrosis (TIF) was graded according to Masson staining. The protein level of ILK was examined by Western blot. Tissue/cytological expression for ILK, alpha-SMA and E-cadherin were investigated by immunohistochemistry. The mRNA levels of ILK, alpha-SMA and E-cadherin were analyzed by quantitative real-time PCR.

RESULTSIn the control animals (group C), weak staining for ILK was detected mainly in the podocytes. Significant increase of staining for ILK in the experimental mice (UUO group) was detected from day 1 onward (t = 16.5, P < 0.01), reaching the peak at day 7. The protein expression of E-cadherin was continuously down-regulated from day 3 onward after surgery (t = 21.0, P < 0.01), while expression for alpha-SMA was up-regulated. From day 1 to day 7, the protein expression of ILK was positively correlated with alpha-SMA (R = 0.88, P < 0.01), but negatively correlated with E-cadherin (R = -0.87, P < 0.01). The mRNA expression of ILK and alpha-SMA analyzed by real-time PCR increased from postoperative day 1 and 3 respectively, but the mRNA expression of E-cadherin decreased from day 3 onward.

CONCLUSIONIncreasing expression of ILK occurs in the early phase of UUO mouse and may play an important role in the process of TIF through mediating the epithelial-mesenchymal transition.

Actins ; biosynthesis ; genetics ; Animals ; Blotting, Western ; Cadherins ; biosynthesis ; genetics ; Epithelial Cells ; metabolism ; pathology ; Fibrosis ; Immunohistochemistry ; Kidney Tubules ; metabolism ; pathology ; Male ; Mesoderm ; metabolism ; pathology ; Mice ; Muscle, Smooth ; chemistry ; Protein-Serine-Threonine Kinases ; biosynthesis ; genetics ; RNA, Messenger ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Ureteral Obstruction ; genetics ; metabolism ; pathology

OBJECTIVETo study effect and mechanisms of tetramethylpyrazine (TMP) on renal interstitial fibrosis induced by unilateral ureteral obstruction in rats.

METHODEighteen male Sprague-Dawley rats were randomly divided into sham-operated group, model group and TMP group, 6 in each group. The model of renal interstitial fibrosisi was established in rats by unilateral ureteral obstruction. All rats were killed at the end of the 3rd week after treatment. Pathological change and collagen deposition of the kidneys in rats were observed with HE staining and Masson's collagen staining, respectively. The contents of procollagen III N-terminal peptide and TGF-beta 1 in renal tissue homogenates were tested by radioimmunoassay and ELISA, respective. Protein expression levels of Smad 7 and the Smad transcriptional corepressors SnoN in the obstructed kidney were analyzed by Western blotting.

RESULTPathological examination of the kidneys in the model group showed renal tubule atrophied and lumens expanded, tubular interstitium broadened, large amount of collagen interstitial deposited. The contents of procollagen III N-terminal peptide and TGF-beta 1 were higher and the protein expression levels of Smad7 and SnoN were significantly lower than those in the sham-operated group. Compared with the model group, TMP ameliorated the pathological lesion of the obstructed kidney, decreased the procollagen III N-terminal peptide and TGF-beta 1 contents, significantly increased the expression levels of Smad7 and SnoN protein.

CONCLUSIONTMP can evidently resist renal interstitial fibrosis induced by UUO in rats, which might be related with down-regulation of the contents of TGF-beta 1, which is a potent profibrosis cytokine, meanwhile up-regulation of the protein expression levels of Smad7 and SnoN in renal tissue.

Animals ; Body Weight ; drug effects ; Collagen ; metabolism ; Gene Expression Regulation ; drug effects ; Kidney ; drug effects ; pathology ; Male ; Nerve Tissue Proteins ; metabolism ; Peptide Fragments ; metabolism ; Procollagen ; metabolism ; Pyrazines ; pharmacology ; Rats ; Smad7 Protein ; metabolism ; Transcription Factors ; metabolism ; Transforming Growth Factor beta ; metabolism ; Ureteral Obstruction ; metabolism ; pathology ; physiopathology

BACKGROUND/AIMS: There has been controversy about the role of Toll-like receptor 2 (TLR2) in renal injury following ureteric obstruction. Although inhibition of the renin angiotensin system (RAS) reduces TLR2 expression in mice, the exact relationship between TLR2 and RAS is not known. The aim of this study was to determine whether the RAS modulates TLR2. METHODS: We used 8-week-old male wild type (WT) and TLR2-knockout (KO) mice on a C57Bl/6 background. Unilateral ureteral obstruction (UUO) was induced by complete ligation of the left ureter. Angiotensin (Ang) II (1,000 ng/kg/min) and the direct renin inhibitor aliskiren (25 mg/kg/day) were administrated to mice using an osmotic minipump. Molecular and histologic evaluations were performed. RESULTS: Ang II infusion increased mRNA expression of TLR2 in WT mouse kidneys (p < 0.05). The expression of renin mRNA in TLR2-KO UUO kidneys was significantly higher than that in WT UUO kidneys (p < 0.05). There were no differences in tissue injury score or mRNA expression of monocyte chemotactic protein 1 (MCP-1), osteopontin (OPN), or transforming growth factor beta (TGF-beta) between TLR2-KO UUO and WT UUO kidneys. However, aliskiren decreased the tissue injury score and mRNA expression of TLR2, MCP-1, OPN, and TGF-beta in WT UUO kidneys (p < 0.05). Aliskiren-treated TLR2-KO UUO kidneys showed less kidney injury than aliskiren-treated WT UUO kidneys. CONCLUSIONS: TLR2 deletion induced activation of the RAS in UUO kidneys. Moreover, inhibition of both RAS and TLR2 had an additive ameliorative effect on UUO injury of the kidney.
Amides/*pharmacology ; Angiotensin II/pharmacology ; Animals ; Disease Models, Animal ; Fibrosis ; Fumarates/*pharmacology ; Kidney/*drug effects/metabolism/pathology ; Male ; Mice, Inbred C57BL ; Mice, Knockout ; Nephritis, Interstitial/genetics/metabolism/pathology/*prevention & control ; RNA, Messenger/genetics/metabolism ; Renin/*antagonists & inhibitors/metabolism ; Renin-Angiotensin System/*drug effects ; Toll-Like Receptor 2/deficiency/drug effects/genetics/*metabolism ; Ureteral Obstruction/*drug therapy/genetics/metabolism/pathology