OBJECTIVETo determine the effect of hypercholsterolemia induced by a high-lipid diet on glomerulosclerosis.

METHODSTwenty nephrotic syndrome (NS) Wistar rats administrated adriamycin (ADR) with a single intravenous dose of 5 mg/kg body weight, were divided into the standard and high-lipid chow groups. Another 20 weight-matched non-NS rats that received a vehicle alone were grouped as control. Urinary protein excretion and serum cholesterol were assayed; image analysis and techniques of pathology, immunohistochemistry, and molecular biology were used to determine morphological changes in glomeruli and the production of glomerular mesangial matrices in different groups.

RESULTSThe serum total cholesterol level was significantly higher in rats with high-lipid chow in both non-NS [(2.2 +/- 0.3) g/L vs. (0.9 +/- 0.1) g/L, P < 0.01] and NS [(9.5 +/- 0.2) g/L vs. (2.3 +/- 0.3) g/L, P < 0.01]. The urinary protein excretion was significantly higher in the high-lipid diet rats than in standard chow rats [(76.2 +/- 24.2) mg/24h vs. (44.8 +/- 13.6) mg/24h, P < 0.05] in NS rats. Although increases in the mesangial matrix and mesangial cells were observed in rats with high-lipid diet in both NS and non-NS group, more obvious pathological changes were found in NS group, such as lipid deposits and foam cell formation in mesangial areas, and progressing to focal and segmental glomerulosclerosis in some glomeruli. The immunohistochemical asay showed that the production of 3 major components (collagen IV, fibronectin, and laminin) was increased in NS group, especially in the rats with high-lipid chow. The increased expression of laminin mRNA was also detected with slot blotting in both NS and non-NS rats with high-lipid chow, and it was more obvious in the rats with NS.

CONCLUSIONOur findings indicated that diet-induced hyperlipidemia can lead to over-production of mesangial matrix components, and further aggravate glomerulosclerosis in ADR-induced nephrosis.

Animals ; Dietary Fats ; pharmacology ; Doxorubicin ; Fibronectins ; metabolism ; Glomerular Mesangium ; metabolism ; pathology ; Hypercholesterolemia ; metabolism ; Laminin ; metabolism ; Male ; Nephrotic Syndrome ; chemically induced ; metabolism ; pathology ; Proteinuria ; urine ; Rats ; Rats, Wistar

BACKGROUND: Transforming growth factor-beta (TGF-beta) stimulates renal fibrosis in various renal diseases including IgA nephropathy. METHODS: We examined whether immunoglobulin A (IgA) stimulated TGF-beta1 synthesis in human mesangial cells (MCs), and whether this effect was mediated through the protein kinase C (PKC) pathway. We measured the intraglomerular TGF-beta1 mRNA expression by using competitive RT-PCR, and this was compared with various parameters in IgA nephropathy patients. RESULTS: The IgA aggregate increased the TGF-beta1 mRNA expression in MCs, while this expression was not affected by the culture media or IgG aggregate. Phorbol 12-myristate 13-acetate and calphostin C did not influence the TGF-beta1 mRNA expression that was increased by the IgA aggregate. Intraglomerular TGF-beta1 mRNA expression was significantly correlated with creatinine clearance (r=-0.764, p=0.027), daily proteinuria (r=0.781, p=0.022), serum creatinine (r=0.884, p=0.004), and tubulointerstitial changes (r=0.809, p=0.015). Glomerular TGF-beta1 mRNA expression was associated with an increased tendency for glomerulosclerosis (r=0.646, p=0.084). After 4 years, patients with a high expression of intraglomerular TGF-beta1 mRNA showed a tendency for an decrease of their renal function. CONCLUSION: The IgA aggregate increased TGF-beta1 mRNA expression in MCs, and this was independent of the PKC pathway. The evaluation of intraglomerular TGF-beta1 mRNA expression could be useful in predicting the progression of IgA nephropathy.
Cells, Cultured ; Female ; Glomerular Mesangium/*cytology/metabolism ; Glomerulonephritis, IGA/metabolism/pathology ; Humans ; Immunoglobulin A/*pharmacology ; Male ; Proteins/*metabolism ; RNA, Messenger/*metabolism ; Research Support, Non-U.S. Gov't

OBJECTIVETo study the clinicopathologic features of membranous nephropathy coexisting with IgA nephropathy.

METHODSThe renal biopsies performed in Peking University First Hospital during the period from January, 1998 to April, 2006 were retrospectively reviewed. The clinicopathologic features of 11 cases of membranous nephropathy coexisting with IgA nephropathy were studied. Electron microscopy with immunogold labeling for IgG and IgA were also performed.

RESULTSThe mean age of patients was 39.9 years. The male-to-female ratio was 1:2.9. The patients mainly presented with proteinuria. Proteinuria of nephrotic level was seen in 7 cases (63.6%). Seven cases also had associated microscopic hematuria. None of them showed evidence of renal insufficiency. Cases with secondary diseases, such as hepatitis virus infection and systemic lupus erythematosus, were excluded from the study. Histologically, vacuolation and thickening of glomerular basement membrane was seen. There was also mild mesangial hypercellularity and increase in mesangial matrix. Occasional glomeruli with crescent formation were identified in 2 cases. Immunofluorescence study showed granular staining for IgG and C3 along glomerular capillary walls, in addition to clumps of IgA deposits in mesangium. Electron microscopy revealed subepithelial and mesangial electron-dense deposits. Immunogold labeling showed IgG and IgA localized in the subepithelial and mesangial deposits respectively.

CONCLUSIONMembranous nephropathy coexisting with IgA nephropathy possesses the clinicopathologic features of both components. It might be caused by independent occurrence of the two entities.

Adult ; Female ; Glomerular Basement Membrane ; immunology ; pathology ; ultrastructure ; Glomerular Mesangium ; immunology ; pathology ; ultrastructure ; Glomerulonephritis, IGA ; complications ; immunology ; pathology ; Glomerulonephritis, Membranous ; complications ; immunology ; pathology ; Humans ; Immunoglobulin A ; metabolism ; Immunoglobulin G ; metabolism ; Kidney Glomerulus ; immunology ; pathology ; ultrastructure ; Male ; Middle Aged ; Retrospective Studies

OBJECTIVETo explore whether there is phenotypic modulation of mesangial cells in streptozotocin (STZ) induced diabetic rats and study the effect of Tujian Mixture (TJM) on it.

METHODSSD rats were divided into the normal control group (NC group, n = 8), the unilateral nephrectomized control group (QC group, n = 8), the STZ induced diabetes mellitus with unilateral nephrectomy model group (DM group, n = 8), the Valsartan treated group (VT group, n = 8) and the TJM treated group (ZY group, n = 9), rats in the latter two groups were modeled as in the DM group and treated with Valsartan (20 mg/kg.d) and TJM (20 g/kg.d) respectively for 12 weeks. The expression of alpha-smooth muscle actin (alpha-SMA) and transforming growth factor-beta 1 (TGF-beta 1) in rats glomeruli were observed by immunohistochemistry assay, and the ratio of alpha-SMA and TGF-beta 1 positive area/total glomerule tuft area (SMA/GT and TGF/GT) were analyzed using computer-assisted image analysis software.

RESULTSIn the NC and the QC groups, only trace of alpha-SMA positive staining was found. But there was prominant alpha-SMA positive staining in glomeruli of the DM group, with SMA/GT and TGF/GT increased significantly (P < 0.01), and marked increase of 24 hrs proteinuria excretion (P < 0.01). As compared with the DM group, the three indexes were all significantly lower in the VT and ZY groups (P < 0.01), and the lowering of proteinuria was more significant in the ZY group than that in the VT group (P < 0.01).

CONCLUSIONThe expression of alpha-SMA in glomeruli in STZ induced diabetic rats with unilateral nephrectomy is pronounced, indicating that phenotypic modulation of mesangial cells involvement in the pathogenesis of diabetic nephropathy. TJM and Valsartan can reduce 24 hrs proteinuria excretion, inhibit the phenotypic modulation of mesangial cells and the expression of TGF-beta 1 in glomeruli of diabetic rats, and the effect of TJM is more potent than that of Valsartan in lowering urinary protein excretion.

Animals ; Diabetes Mellitus, Experimental ; metabolism ; pathology ; Diabetic Nephropathies ; etiology ; metabolism ; pathology ; Drug Combinations ; Drugs, Chinese Herbal ; pharmacology ; Glomerular Mesangium ; metabolism ; pathology ; Image Processing, Computer-Assisted ; Male ; Nephrectomy ; Phenotype ; Rats ; Rats, Sprague-Dawley ; Transforming Growth Factor beta ; metabolism

Diabetic nephropathy is characterized by an expansion of the glomerular mesangium, caused by mesangial cell proliferation and an excessive accumulation of extracellar matrix (ECM) proteins, which eventually leading to glomerulosclerosis. TGF-beta1 was found to play an important role in the accumulation of ECM in the kidney. In this study, TGF-beta1 RNA interference was used as an effective therapeutic strategy. The inhibitory effect of TGF-beta1 small interfering RNAs (siRNAs) on the high glucose-induced overexpression of TGF-beta1 in rat mesangial ceys (RMCs). A high levels of glucose induces TGF-beta1 mRNA and protein, and TGF-beta1 siRNAs reduce the ability of high glucose to stimulate their expression. We also examined the inhibitory effect of TGF-beta1 siRNAs on the expression of plasminogen activator inhibitor (PAI)-1 and Collagen Type I which are down-regulators of TGF-beta1. The expression of TGF-beta1, PAI-1 and Collagen Type I was increased in RMCs that were stimulated by 30 mM glucose. TGF-beta1 siRNAs reduces high glucose-induced TGF-beta1, PAI-1, and Collagen Type I mRNA and protein expression in a dose-dependent manner. In conclusion, the present study demonstrates that TGF-beta1 siRNAs effectively inhibits TGF-beta1 mRNA and protein expression in RMCs. These suggest that TGF-beta1 siRNAs through RNAi may be a useful tool for developing new therapeutic applications for the treatment of diabetic nephropathy.
Transforming Growth Factor beta1/*metabolism ; Rats, Sprague-Dawley ; Rats ; RNA, Small Interfering/*metabolism ; Microscopy, Fluorescence ; Mesangial Cells/*metabolism ; Male ; Glucose/*metabolism ; Glomerular Mesangium/*metabolism ; Gene Expression Regulation ; Diabetic Nephropathies/pathology ; Collagen Type I/metabolism ; Cells, Cultured ; Cell Proliferation ; Animals

OBJECTIVETo study the clinicopathologic features of collagen III glomerulopathy and its cause, pathogenesis and prognosis.

METHODSFive cases of collagen III glomerulopathy that collected from 2005 to 2014 were observed by renal biopsy. The morphologic characteristics were studied by light microscopy, immunofluorescence, immunohistochemical and electron microscopy.

RESULTSThe glomerular mesangium became expansion but no hypercellularity, basement membrane appeared thickened. The glomeruli showed collagen type III deposit by immunohistochemistry method, and collagen fibers increased by electron microscopy. The patients often show serious proteinuria, nephrotic syndrome and renal function damage.

CONCLUSIONSCollagen III glomerulopathy is an idiopathic glomerular disease, characterized by massive accumulation of collagen type III within the glomerular mesangial areas and basement membrane. Collagen III glomerulopathy is extremely rare. The etiology and pathogenesis may relate to the abnormality of collagen III gene. There is no specific treatment for it and its prognosis is poor.

Basement Membrane ; metabolism ; Biopsy ; Collagen Type III ; genetics ; metabolism ; Female ; Fluorescent Antibody Technique ; Glomerular Mesangium ; metabolism ; Humans ; Immunohistochemistry ; Kidney Diseases ; etiology ; pathology ; Kidney Glomerulus ; pathology ; Microscopy, Electron ; Prognosis ; Proteinuria ; diagnosis

OBJECTIVETo study the mechanism of Shenkangwan (SKW) in treating early diabetic nephropathy (DN).

METHODSThe effect of SKW on NO and transforming growth factor (TGF)-beta(1) production by the mesangial cells (MCs) of rats with early diabetic nephropathy was evaluated with serum pharmacological method.

RESULTSCompared with normal serum, the SKW-containing serum dose- and time-dependently inhibited TGF-beta(1) excretion and increased NO production in the MCs of rats with early DN (P<0.05 and P<0.01, respectively).

CONCLUSIONThe therapeutic effect of SKW on early DN may rely on the balance modulation of cytokine network by increasing NO production and decreasing TGF-beta(1) excretion to prevent cytokine-induced damage of the MCs.

Animals ; Diabetes Mellitus, Experimental ; drug therapy ; metabolism ; Diabetic Nephropathies ; drug therapy ; metabolism ; Drugs, Chinese Herbal ; therapeutic use ; Glomerular Mesangium ; metabolism ; pathology ; Male ; Nitric Oxide ; biosynthesis ; Rats ; Rats, Wistar ; Transforming Growth Factor beta ; biosynthesis

OBJECTIVESTo inject decorin-transfected mesangial cells (MsC) vector into the kidneys of rats with anti-thy-1 serum-induced nephritis via left renal artery and observe the survival condition of MsC vector and its influence on glomerular lesions in rats with anti-thy-1 serum induced nephritis.

METHODSRat mesangio-proliferative glomerulonephritis was established by tail intravenous injection with rabbit anti-thy-1 serum (ATS). Decorin-transfected MsC was injected into rat kidneys via left renal artery. Primary culture, immunostaining for BrdU and decorin of transfected MsC lines were performed to observe their survival. Immunohistochemistry with image analysis was performed to detect the expression of BrdU, alpha-SMA, decorin, TGF-beta1, FN and ColIV in diseased glomeruli.

RESULTSRat anti-thy-1 serum-induced nephritis identified by pathological examination was successfully established by injecting rabbit ATS, and decorin transfected MsC vector was transfused to rat glomeruli via left renal artery. The active growth and positive expressions of BrdU and decorin proteins on the nuclei and cytoplasms of ex vivo MsC were observed respectively. TGF-beta1, FN, ColIV expressions in diseased glomeruli of rats with ATS nephritis were decreased significantly at day 4 (TGF-beta1, P < 0.05) and day 2 (FN and ColIV, P < 0.01) respectively, compared to uninjected kidneys.

CONCLUSIONSMsC vector is successfully transferred to the glomeruli of experimental rats via left renal artery injection with no affect on cell survival. Decorin protein is expressed on the transfected MsC and shows antagonistic effect on the glomerular lesions of ATS rats. It suggests that the use of ex vivo MsC vector system can provide useful experimental basis for gene therapy of kidney disease in animal model.

Animals ; Decorin ; Disease Models, Animal ; Extracellular Matrix Proteins ; Genetic Therapy ; Glomerular Mesangium ; metabolism ; Glomerulonephritis, Membranoproliferative ; pathology ; therapy ; Immune Sera ; immunology ; Kidney Glomerulus ; pathology ; Proteoglycans ; genetics ; Rats ; Thy-1 Antigens ; immunology ; Transfection

Hyperglycemia is a principal characteristic of diabetes, and has an influence on many cellular functions. In order to investigate whether the intracellular signaling pathways inducing proliferation, hypertrophy and matrix synthesis of mesangial cells are altered in a diabetic environment, we evaluated the effects of a high concentration of extracellular glucose(25 mM; 450 mg/dl) on [3H]thymidine uptake, hypertrophy, and [3H]proline incorporation into a collagenase-sensitive protein, induced by angiotensin II(Ang II) or transforming growth factor(TGF)-beta, in cultured rat mesangial cells. The exposure to a high glucose concentration for 7 days significantly inhibited Ang II(10(-6) M)-induced [3H]thymidine uptake, compared to normal glucose concentration (5 mM)(M +/- SD., 1050 +/- 100 cpm/well vs 550 +/- 97, p< 0.05), and markedly prevented the inhibition of [3H]thymidine uptake by TGF-beta(1 ng/ml)(132 +/- 10 vs 340 +/- 67, p< 0.05). The administration of H-7(50 microM), a protein kinase C(PKC) inhibitor, did not reverse these effects of high glucose on [3H]thymidine uptake. On flow cytometric analysis of cell size, the mean cell size was significantly greater for the cells exposed to high glucose or treated with Ang II or TGF-beta, compared to that for the untreated cells. But the addition of Ang II or TGF-beta to the cells exposed to high glucose did not show further enlargement in size. The exposure to high glucose and the treatment with Ang II or TGF-beta significantly increased collagen synthesis, measured by [3H]proline incorporation. The Ang II -or TGF-beta-induced increase of [3H]proline incorporation did not show changes under high glucose culture condition, compared to normal glucose concentration(Ang II, 27880 +/- 3560 cpm vs 26978 +/- 2284, TGF-beta, 26559 +/- 3700 vs 25800 +/- 1660, p> 0.05). In conclusion, although the signaling pathway for DNA synthesis by Ang II or TGF-beta are influenced, possibly mediated by PKC-independent mechanism(s), the pathway inducing hypertrophy or collagen synthesis by both agents appears to be unchanged under the high extracellular glucose concentration in cultured rat mesangial cells.
Angiotensin II/*pharmacology ; Animal ; Cells, Cultured ; Collagen/*biosynthesis ; DNA/*biosynthesis ; Glomerular Mesangium/metabolism/*pathology ; Glucose/*toxicity ; Hypertrophy ; Rats ; Rats, Sprague-Dawley ; Support, Non-U.S. Gov't ; Transforming Growth Factor beta/*pharmacology

OBJECTIVETo investigate whether FTY720 inhibits rat mesangial proliferation and extracellular matrix expansion through suppression of transforming growth factor β1-connective tissue growth factor (TGFβ1-CTGF) pathway, and to explore experimental evidence for its effect on mesangial proliferative glomerulonephritis.

METHODSA rat model of anti-Thy-1 mesangial proliferative glomerulonephritis was established and FTY720 intervention was performed. Periphery blood lymphocyte count, urine protein excretion, glomerular mesangial proliferation, protein and gene expression of TGFβ1 and CTGF and extracellular matrix protein including fibronectin, laminin and collagen IV in isolated glomeruli were documented at 1, 3 and 7 days after injection of anti-Thy-1 antibody.

RESULTSThe model group developed proteinuria at 1, 3 and 7 days after injection of anti-Thy-1 antibody, which were significantly higher [(27.9 ± 7.3), (63.5 ± 18.8) and (52.4 ± 15.4)mg/d, respectively] than those in the control group [(8.4 ± 2.4), (8.4 ± 2.1) and (10.4 ± 3.2) mg/d; respectively, P < 0.01]. FTY720 intervention group showed significantly decreased proteinuria at 3 and 7 days after injection [(31.4 ± 7.0), (25.5 ± 7.7) mg/d, respectively] than model group (P < 0.01), although higher than the control group (P < 0.01). After intervention for 3 and 7 days, FTY720 significantly down-regulated both TGFβ1 and CTGF gene and protein expression in cultured glomeruli, and suppressed the production of glomerular extracellular matrix protein secretion, leading to attenuated mesangial cell proliferation and extracellular matrix expansion in rat anti-Thy-1 mesangial proliferative glomerulonephritis.

CONCLUSIONFTY720 significantly attenuates mesangial proliferation and extracellular matrix expansion through inhibition of TGFβ1-CTGF pathway in rat, and thus ameliorates the development of anti-Thy-1 mesangial proliferative glomerulonephritis.

Animals ; Cell Proliferation ; Connective Tissue Growth Factor ; genetics ; metabolism ; Down-Regulation ; Extracellular Matrix Proteins ; metabolism ; Fingolimod Hydrochloride ; Gene Expression ; Glomerular Mesangium ; metabolism ; pathology ; Glomerulonephritis, Membranoproliferative ; immunology ; metabolism ; pathology ; Immunosuppressive Agents ; pharmacology ; Isoantibodies ; immunology ; Kidney Glomerulus ; metabolism ; pathology ; Male ; Propylene Glycols ; pharmacology ; Proteinuria ; urine ; Rats ; Rats, Wistar ; Signal Transduction ; drug effects ; Sphingosine ; analogs & derivatives ; pharmacology ; Thy-1 Antigens ; immunology ; Transforming Growth Factor beta1 ; genetics ; metabolism