Objective    To elucidate the clinicopathological and hereditary characteristics in Fabry nephropathy.    Methods    The clinical and pathological features of 14 patients with Fabry nephropathy were collected. The activities of α?Gal A were measured in 4 probands. Screenings of GLA mutations were done in 12 patients.    Results    The ratio of Fabry nephropathy in the patients with renal biopsy was 0.074 % (14/19 005), the average diagnostic age was (30.57±9.32) years, male to female ratio was 2.5∶1. All the patients had proteinuria, and the median of urine total protein (UTP) was 1.71 g/24 h (0.32?4.71 g/24 h). Two of them got nephrotic proteinuria, 5 of them got microscopic hematuria, 4 of them got renal function insufficiency. Angiokeratomas was the most common manifestation (10/14), followed by cardiac involvement (6/14). Hypohidrosis and diseases of central neural system could also be seen in these patients. There were 9 classic phenotype, the remaining 5 were variants/renal variants. The family information was collected in 10 pedigrees, 6 of them had family histories of kidney disease. Renal pathology showed vacuolization of glomerular visceral epithelial cells was the prominent feature, global and segmental glomerulosclerosis were seen in some patients by light microscopy.  The myelin bodies or zebra bodies were identified in podocytes by electron microscopy, but only were found in some podocytes of 2 females. The activity of α?Gal A was decreased compared with the normal range in 4 probands. The mutations of GLA were demonstrated in 11 patients. Three novel mutations of GLA gene were identified, which were all deletion/insertion mutations with classic phenotypes. Most variants carried the mutations located in the buried/partial buried areas of α?Gal A (3/11). The classical phenotype carried GLA mutations as W162X, F169S, S201F, N272K, L310R, while variant phenotype carried GLA mutations as I91T, R112H, Q312H.    Conclusions    The ratio of Fabry nephropathy in patients with renal biopsy is 0.074%. Angiokeratomas and cardiac involvement are often accompanied with Fabry nephropathy. The genotypes of GLA may have close relationships with the phenotypes of Fabry nephopathy.

Objective    To investigate the association of radial arterial calcification damage with bone mineral density (BMD) and bone metabolism biomarkers in uremia patients.    Methods    Sixty-seven incident hemodialysis patients were recruited into uremic group. Serum creatinine, calcium, phosphorus, lumbar spine and femoral neck BMD were measured. Parathyroid hormone (iPTH), 25OHD, 1,25(OH)2D, fibroblast growth factor (FGF) 23, bone specific alkaline phosphates (BAP) and osteocalcin (BGP), type I collagen pyridine crosslinked C?telopcptidc (ICTP) were detected. Radial artery calcification was analyzed by von Kossa staining and transmission electron microscopy. Arterial type Ⅰ collagen (ColⅠ) expression was examined. Twenty?three healthy cases received serum and BMD examination only as control.    Results    Uremic patients presented higher serum phosphate, iPTH, FGF23, lower serum calcium, 25OHD, 1,25 (OH)2D (all P＜0.05), and lower lumbar spine and femoral neck BMD (all P＜0.01) compared to controls. Significant calcium deposit was observed in radial arteries in 24 uremic cases (35.8%), including 10 cases of diabetes. Immunohistochemistric assay confirmed that ColⅠexpression increased around calcification site and electron microscope revealed that more calcium and phosphorus plaque attached among collagen fibers. No correlation was showed between iPTH and radial artery calcification (r＝-0.08, P＝0.306), but after stratified by iPTH levels, correlation of iPTH and calcification was found in low iPTH (＜150 ng/L) group and high iPTH group   (＞300 ng/L) (r＝-0.41, 0.31, P＝0.044, 0.023). Diabetes, lumbar spine and femoral neck BMD, ICTP, FGF23 were correlated with arterial calcification (r＝0.62, -0.25, -0.43, 0.34, 0.86, P＝0.000, 0.001, 0.012, 0.018, 0.000). Multiple regression analysis showed femoral neck BMD, ICTP, FGF23 levels were independently associated with radial arterial calcification (β＝-0.221, 0.181, 0.260, P＝0.021, 0.024, 0.036).    Conclusion    In uremic patients, reduced BMD, abnormal bone turnover rate, especially accelerated bone reabsorption, and increased serum FGF23 level are independently associated with radial artery calcification.
  

Objective    To investigate the expression and distribution of parathyroid hormone (PTH) in renal tissues of early stage chronic kidney disease (CKD), and to elucidate its potential role in renal lesion.    Methods    Eighty-two patients of early stage CKD (stage 1 and 2) diagnosed as glomerulonephritis (GN) with different pathologic types by renal biopsy in our department between 2009 and 2012 were enrolled in the study. Renal tissues of eight patients with mismatched HLA haplotype or the normal part of renal cancer were chosen as controls. Scr, BUN, serum calcium, phosphorus, PTH and 25(OH)VitD3 were measured. Creatinine clearance (Ccr) was calculated by Cockcroft?Gault (CG) formula. 99mTc?DTPA clearance rate was used to detect GFR. Patients were divided into mild, moderate and severe groups according to the renal interstitial extent of inflammatory cells infiltration. Immunohistochemistry was used to observe the expression and distribution of PTH in renal tissues. Image-Pro Plus software was used to calculate A value of PTH in renal tissues and compare the extent of PTH expression.    Results    The levels of calcium, phosphorus, 25(OH)VitD3 and PTH in peripheral blood from GN patients of CKD stage 1 and 2 were normal. PTH had no correlation with the above indexes. PTH expression could be seen in renal tissues of all the GN patients with different pathologic types, and it mainly located in renal tubular, only a few in glomeruli and interstitium. The expression of PTH in renal tissues of GN increased compared with the controls (P＜0.01). Furthermore, PTH expression elevated with the increase of inflammatory cells infiltration in interstitium. However the expression of PTH was not significantly different among different pathologic types of GN.    Conclusions    In the early stage CKD, PTH expression in patients of GN increases, which occurs earlier as compared to PTH elevation in peripheral blood and the imbalance of minerals and bone metabolism. The intensity of PTH expression is associated with the local inflammation.

Objective    To investigate the efficacy of N?acetylcysteine on prevention of contrast?induced nephropathy (CIN).    Methods    According to the regulation of evidence?based medicine, the selection criteria, elimination criteria and search strategy were defined. PubMed, Cochrane Library, Wiley Online Library and Google Scholar were searched. The literature limited range was from January 2000 to December 2011. Two investigators extracted the data independently from all the studies that accorded with selection criteria using a suitable form. All the statistical analyses were performed with RevMan version 5.1.    Results    A total of 151 potential literatures were screened and 16 remained literatures (including 4588 patients) were identified to accord with the criteria in this meta?analysis. In 14 literatures, the Jadad score was 3  at least. The meta?analysis of 16 trials showed N?acetylcysteine could prevent CIN from happening [odds ratio (OR)=0.65，95% CI 0.46?0.92, P=0.01]. In the groups of average Scr baseline＜132.6 μmol/L, result displayed the OR of incidence associated with N?acetylcysteine for prevention of CIN was 0.93 (95% CI 0.75?1.15, P=0.49). In the groups of average Scr baseline ≥132.6 μmol/L, the OR for N?acetylcysteine associated with incidence of CIN was 0.52 (95% CI 0.30?0.93, P=0.03).    Conclusion    There is specific effect that N?acetylcysteine prevents CIN from happening in the groups of average Scr baseline ≥132.6 μmol/L.

Objective    To study the prevalence and associated factors of secondary hyperparathyroidism (SHPT) in continuous ambulatory peritoneal dialysis (CAPD) patients.    Methods     A cross-section study was performed. A total of 639 eligible participants undergoing CAPD treatment more than three months in our peritoneal dialysis center from July 2011 to January 2012 were recruited in the study. All the patients were divided into SHPT group and non-SHPT group according to the intact parathyroid hormone (iPTH) level, and the associated factors of SHPT were investigated through Logistic regression analysis.    Results    The prevalence of SHPT was 46.95% (300/639). Logistic regression analysis demonstrated that lower hemoglobin, hypocalcemia, hyperphosphatemia, higher alkaline phosphatase, higher Scr, higher nPCR and low calcium dialysate were independent influencing factors of SHPT.    Conclusions    The prevalence of SHPT is quite high in CAPD patients. Abnormal calcium?phosphorus metabolism, renal anemia, high protein diet and low calium dialysate may affect the SHPT.
   

Objective    To explore the clinical features of renal and urinary lesions in IgG4?related disease (IgG4?RD).    Methods    Clinical manifestation, laboratory profiles, iconography images, pathologic findings, treatment and prognosis of 6 IgG4?RD patients with renal and urinary system involvement from Peking Union Medical College Hospital during Aug 2010 to Dec 2011 were analyzed retrospectively.    Results    Six patients had renal and/or urinary  lesions among IgG4?RD cases diagnosed in our hospital, including 4 males and 2 women, with median age of 59 years (36 to 72 years) and median disease course of 10.5 months. All the patients presented multiple organ involvement simultaneously. Urinary system lesion varied, including renal dysfunction, abdominal pain and edema. Hyperglobulinemia, elevated serum IgG (median 23.3 g/L) and IgG4 (median 4227.0 mg/L), tubular proteinuria were found in all the 6 patients, and elevated Scr (median 237 μmol/L) in 5 cases. Kidney CT image often showed renal swelling, hydronephrosis, multiple low density focus with attenuation and kidney atrophy. Renal pathology revealed interstitial inflammatory cells infiltration comprising predominantly plasma cells and lymphocytes, with a high prevalence of IgG4?positive cells often admixed with fibrosis, which fit the features of tubulointerstitial nephritis. Patients with IgG4?RD nephropathy presented good response to glucocorticoids. After therapy, the symptoms were improved and serum IgG, IgG4 and Scr decreased.    Conclusions    Renal and urinary lesions of IgG4?RD are heterogeneous in clinical manifestation, and are often complicated with various organ lesions. The feature of renal histopathology is tubulointerstitial nephritis infiltrated by plasma cells and lymphocytes with positive IgG4. Glucocorticoids treatment is effective for this disease.
   

Objective    To investigate the effect and significance of regulating endoplasmic reticulum stress on the expression of histone methyltransferases SET7/9 in the kidneys of db/db mice.    Methods    Db/db mice were randomly divided into two groups according to random number table method: diabetic nephropathy model group (DN group, n＝18) and betaine treatment group (DN+B group, n＝18), db/m mice were defined as normal control group (NC group, n＝18). At the end of 4, 8 and 12 weeks, the expression of GRP78, SET7/9, H3K4me2, and monocyte chemoattractant protein 1(MCP-1) was determined by real-time fluorescence PCR and Western blotting. 24?hour urinary protein excretion rate (UPER) and urine MCP-1 were measured by enzyme linked immunosorbent assay (ELISA). The dynamic changes of blood glucose(BG), serum creatinine (Scr), blood urea nitrogen (BUN) were tested by completely automatic biochemistry analyzer. The morphology of kidney was estimated by special staining of periodic acid-schiff (PAS).    Results    The levels of BG, BUN, UAER and MCP-1 were significantly higher in DN group than those in NC group  (P＜0.05), and were in time?dependent manner. Glomerular basement membrane thickening and mesangial cells proliferation began to emerge in DN group at the end of week 4 and mesangial matrix expansion was more obvious at the end of week 12. The mRNA and protein expression of GRP78 and SET7/9 were elevated significantly in DN group as compared to NC group. The H3K4me2 protein expression level was also increased in time-dependent manner. Compared with the DN group, in DN+B group glomerular lesions attenuated and the GRP78 and SET7/9 expression levels obviously decreased (P＜0.05). Furthermore, the levels of BG, BUN, UPER, MCP-1, H3K4me2 in DN+B group were also reduced (P＜0.05).    Conclusion    Endoplasmic reticulum stress may be the upstream mechanism of mediating the expression of SET7/9 in the kidneys of DN mice.    
  

Objective    To investigate whether high glucose can induce endothelial-mesenchymal transition (EndMT) in glomerular endothelial cells and the role of TGF-β in the process. Methods    Rat glomerular endothelial cells were divided into five groups: normal glucose (NG, 5.5 mmol/L), high glucose (HG, 15, 30 mmol/L), TGF-β inhibition (HG+LY36, 30 mmol/L glucose+10     μmol/L LY364947), hyperosmotic control (M, 5.5 mmol/L glucose+25.5 mmol/L mannitol) and solvent control (D, 5.5 mmol/L glucose+1 ml/L DMSO). Western blotting was performed to detect relative protein quantities of endothelial marker claudin 5 and mesenchymal marker α-smooth muscle actin         (α-SMA). TGF-β1 and TGF-β2 mRNA levels were measured by real-time PCR. Vascular endothelial marker VE-cadherin and mesenchymal marker α-SMA were detected by immunofluorescent stain and observed by confocal microscopy.    Results    Compared with NG, the expression of claudin5 protein in HG (15 or 30 mmol/L) was up-regulated while expression of α-SMA protein was down-regulated (P＜0.05). Both TGF-β1 and TGF-β2 mRNA levels increased as well (P＜0.05). However, when compared with HG, the claudin 5 levels increased while α-SMA decreased in TGF-β inhibition group. No significant changes were observed in hyperosmotic or solvent control group. Confocal microscopy showed the transformation of cells from a cobblestone-liked shape to a spindle one, and a decreasing expression of VE-cadherin while an increasing α-SMA in HG group (P＜0.05), whereas TGF-β inhibition partly attenuated those changes in both morphological and protein levels.    Conclusions    High glucose treatment of glomerular endothelial cells results in an increase in the level of TGF-β1 and TGF-β2 mRNA and leads to endothelial-mesenchymal transiton. Inhibition of TGF-β partly prevents this process, indicating that TGF-β plays a crucial role in high-glucose-induced glomerular endothelial-mesenchymal transiton.

Objective     To investigate the effects of hepatitis B virus X (HBX) gene on cell morphology and transdifferentiation of human proximal tubular epithelial cells.    Methods    The eukaryotic vector pcDNA3.1-myc-HBX containing HBX gene was transiently transfected into HK-2 cells by lipofectamine mediation. The expression of HBX was confirmed by Q-PCR and Western blotting. Untransfected HK-2 cells and those transfected with empty vector were used as control. The morphology of HK-2 cells was observed by microscopy, the expressions of differentiation marker proteins α-SMA and E-cadherin were detected by Western blotting and Q-PCR, and the contents of IL-1, IL-6 and TNF-α in the supernatant were detected by ELISA assay.    Results    HBX was successfully expressed in HK-2 cells after transfection. After transfection of HBX gene, the shape of HK-2 cells became irregular, HK-2 cells significantly expressed E-cadherin and α-SMA, and had high levels of IL-1, IL-6 and TNF-α in the cell supernatant (P<0.01).    Conclusion    Overexpression of HBX gene in renal tubular epithelial cells may damage cell morphology and promote the occurrence of epithelial-mesenchymal transdifferentiation, which may be related to the inflammatory microenvironment.

Objective    To investigate the protective effects of recombinant human erythropoietin (rHuEPO) on caecal ligation and puncture (CLP)?induced acute kidney injury (AKI).    Methods    A total of 260 healthy male Sprague?Dawley rats (250?300 g) were randomly divided into 6 groups: normal control group, sham group, CLP model group, the large dose rHuEPO (5000 U/kg) group, the middle dose rHuEPO (1000 U/kg) group, and the small dose rHuEPO (500 U/kg) group. The rat models of sepsis were established by CLP. In treatment groups, rats were treated with rHuEPO through caudalis injection after CLP surgery. Each group was divided into 2?, 6?, 12?, 24?, 36?hour subgroups with 10 rats. Rats were sacrificed and the tissue samples including kidney and blood samples were collected. The kidney function, plasma cytokines [interleukin 6 (IL?6) and tumor necrosis factor alpha (TNF?α)], kidney injury moleclue 1 (KIM?1) and inducible nitric oxide synthase (iNOS) were measured. Cytokines were determined by ELISA method. The expression of nuclear factor?kappaB (NF?κB) protein in  kidneys were detected by immnunohistochemistry method. Pathological changes of kidney tissues were observed by light and transmission electron microscopy for cytokine content and apoptosis.    Results    Compared with CLP model group, renal function, the levels of TNF?α, IL?6, KIM?1 and iNOS in serum, the expression of NF?κB, significantly decresed in large dose rHuEPO group (all P＜0.05). rHuEPO also lessened the histological changes in large dose group. rHuEPO did not lessen the histological changes in others.    Conclusion    rHuEPO can inhibit the levels of TNF?α, IL?6 and iNOS in serum, thus modify the inflammatory response and provide protective effects against acute kidney injury induced by sepsis.