Objective To evaluate the effect of sevelamer hydrochloride on parameters of coronary artery calcification(CAC), mineral metabolism and lipid profile in maintenance hemodialysis (MHD) patients. Methods Medline, CENTRAL and Chinese biomedical database were retrieved by using the key words "sevelamer or Renagel" so as to search the materials about the randomized controlled clinical trials that had compared the effects of sevelamer and calcium-based phosphate binders(CBPB) on cardiovascular calcification in MHD patients. A meta-analysis was conducted. Results Five documents about randomized controlled clinical trials, including 697 patients, from the retrieved 276 documents according to the demand of enrollment. Compared with CBPB, there was a significantly lower coronary artery calcification score in MHD patients treated with sevelamer (weighted mean difference -66.84, 95％CI -126.90 to -6.77). The funnel plot test regarding CAC score did not indicate the existence of publication bias. The multiple mortality of sevelamer group was 4.2％, not significantly different from that of CBPB group 5.6％ (RR=0.76, 95％CI 0.37 to 1.57, P=0.45). However, the hospitalization rate of sevelamer group was lower(RR=0.75, 95％CI 0.59 to 0.95, P=0.02). Sensitive analysis confirmed the nonexistence of differences in CAC score and hospitalization rate between these two groups. Conclusions Sevelamer improves the CAC score of MHD patients compared with CBPB. Treatment with sevelamer does not affect overall mortality, but there is evidence for beneficial effect on multiple all-cause hospitalizations.

Objective To elucidate the prevalence and risk factors of acute kidney injury (AKI) within the post-operative 100 days in adult patients with nonmyeloablative hematopoietic stem cell transplantation (HSCT), and whether AKI influences patients’ survival. Methods Sixty-two adult leukemia patients from three transplant centers in Jiangsu province were treated with similar protocols of nonmyeloablative HSCT. AKI was classified as follows: Grade 0, no AKI; Grade 1, renal dysfunction, Scr increased ≥26.5 μmol/L or increased by 50% to 200% (0.5- to 2-fold) from baseline; Grade 2, Scr increased by 200% to 300% (2- to 3-fold) from baseline; Grade 3, Scr increased >300% (>3-fold) from baseline, or Scr ≥ 353.6 μmol/L with an acute increase of at least 44.2 μmol/L. Results 29% (18/62) of the patients developed AKI within 100 days after nonmyeloablative HSCT. Risk factors of AKI were incomplete HLA-matched transplantation [odds ratio (OR) 3.6, 95% confidence interval (CI) 1.1-13.0]. The complications, including sepsis, veno-occlusive disease of liver and acute graft-versus-host, were also associated with the development of AKI (OR 12.1, 95% CI 2.4-62.4). The overall one-year mortality of the patients was 27.4%. AKI was significantly associated with the mortality (log-rank test, P<0.01). Conclusions AKI is a very common complication in the patients with nonmyeloablative HSCT. It is associated with the incomplete HLA-matched transplantation and complications and has an important impact on the patients’ first year survival.

Objective To investigate the association of transforming growth factor β1(TGF-β1) gene -509C/T polymorphism with the susceptibility and the tubulointerstitial damage (TID) degree of primary nephrotic syndrome (PNS) in Han nationality of Chinese population in Hunan province. Methods Ninety-eight PNS patients and 128 healthy controls were enrolled in the study. The TGF-β1 gene-509C/T polymorphism in the 5’-flanking region was detected with the polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) technique, and the serum level of TGF-β1 was determined by enzyme-linked immunosorbent assay (ELISA). The association of TGF-β1 gene －509C/T polymorphism with susceptibility and TID degree of PNS was examined. Results (1) There were 3 genotypes (CC, CT, TT) and 2 allele genes (C, T) of TGF-β1 gene -509 position in PNS and healthy control group. (2) There were no significant differences of genotypes frequency or allele frequency of -509C/T polymorphism in TGF-β1 gene between PNS and healthy control subjects. (3) Significant differences of genotype frequency and allele gene frequency were found among severe TID group of PNS, mild TID group of PNS and healthy control group (all P<0.01）. T allele gene frequency and TT genotype frequency of individuals in severe TID group of PNS were significantly higher than those of other two groups (all P<0.01), while no significant difference was found between mild TID group of PNS and healthy control group. (4) With the development of TID in PNS，the serum TGF-β1 level increased. The serum TGF-β1 level was significantly different among severe TID group of PNS, mild TID group of PNS and healthy control group (all P<0.05), and the serum TGF-β1 level in the individuals with TT genotype was higher than that in those with CC and CT genotype. Conclusions TGF-β1 gene-509C/T polymorphism is not associated with the morbidity of PNS, but associated with the severe degree of TID in PNS. T allele gene may be the important susceptible factor. In addition, the increasing serum TGF-β1 level is associated with the severe degree of TID and TT genotype.

Objective To explore the relationship between the expression of telomerase reverse transcriptase (TERT) and the proliferation of endothelial progenitor cells (EPCs). Methods The bone marrow-derived EPCs form SD rats were cultured in vitro. At the end of week 1, 2, 3 and 4 of culture, MTT assay was used to detect the EPCs proliferation rate in the growth duration; Annexin-V-FITC/PI asaay was applied to examine the apoptosis rate in early stage of EPCs; RT-PCR, immunocytochemistry and Western blotting were employed to detect the TERT mRNA and protein expression. Results The mononuclear cells from rats bone marrow could be induced into endothelial progenitor cells in vitro. The proliferation rate of EPCs from different culture duration took on a singlet curve, with the peak at day 14 (P< 0.01). The apoptosis rate in EPCs was 0.28%, 0.66%, 1.38%, 1.52% respectively at week 1 to 4, increasing along with the growth duration within 28 days. Aging rate of EPCs was 3.04%, 20.28%, 24.36%, 16.52% respectively at the end of 1th, 2th, 3th and 4th weeks, which significantly increased at day 14 (P<0.01) and was highest at day 21, but no significant difference was found. The TERT mRNA and protein expression took on a single curve with its peak at day 14 as well, then reduced with the culture time. Conclusion The down-regulated TERT expression may contribute to the increasing apoptosis rate in early stage and the decreasing proliferaton rate of rat bone marrow-derived EPCs.

Objective To explore the effect of curcumin (Cur) on oxidative stress-induced NRK-52E cells injury. Methods NRK-52E cells were treated with H2O2 at different concentrations as an oxidative stress-induced injury model. Nucleus changes in apoptotic cells were investigated by using Hoechst 33258 staining and photofluorography. Apoptotic rate was evaluated by propidium iodide (PI) staining and flow cytometer (FCM). The expression of Bcl-2 was detected by Western blot assay. Results Apoptosis rate in NRK-52E cells was dose-dependently increased by H2O2 treatment at the concentrations from 100 to 500 μmol/L for 24 h. Expression of Bcl-2 in NRK-52E cells was obviously inhibited by exposure to 500 μmol/L H2O2 (P<0.05). Curcumin, at concentrations of 20 μmol/L and 40 μmol/L, not only decreased an elevated apoptotic rate caused by H2O2[(32.9±8.1)%, (22.23±9.3)% vs (72.7±10.5)%, P<0.05], but also blocked the inhibition of Bcl-2 expression induced by H2O2(P<0.05). Curcumin treatment alone led to an up-regulation of Bcl-2 expression(P<0.05). Conclusions Curcumin significantly protects NRK-52 cells against oxidative stress-induced apoptosis. The cytoprotection may be associated with the inhibition of down-regulation of Bcl-2 expression evoked by H2O2.

Objective To investigate the amelioration mechanism of renal dysfunction by Celecoxib(CXB) through the observation of CXB on Han: SPRD rats with ADPKD. Methods Fifty-seven 3-week-old male Han:SPRD heterozygous(Cy/+) rats were randomly divided into 3 groups(n=19). One group was fed with normal forage(control group), another two groups were fed with low dosage (3 mg&#8226;kg-1&#8226;d-1) and high dosage(10 mg&#8226;kg-1&#8226;d-1) administration of CXB respectively. The BUN and Scr were determined respectively at 3, 5, 7, 9, 12 and 16 weeks. The content of 6-keto-PGF-1α and TXB2 was measured by enzyme-linked immunosorbent assay (ELISA). The expression of TNF-α mRNA was detected by real-time RT-PCR assay. The co-expression of TNF-α and COX-2 was examined by double immunofluorescence labeling technique and laser scanning confocal microscopy. The expression of TNF-α protein was detected by Western blotting. Results BUN and Scr increased continuously in control group and exceeded the normal at 6-week-old and at 8-week-old respectively. At 16-week-old, BUN and Scr were (26.56±9.19) mmol/L and (95.08±67.54) μmol/L. After being treated with CXB, the progression of BUN and Scr was reduced in both low and high dosage group. The content of 6-keto-PGF-1α and TXB2 in low[(1831.68±233.31) ng/L and (156.62±9.29) ng/L] and high dosage group [(1148.57±105.80) ng/L and (157.87±10.16）ng/L] was significantly lower than those in control group [(2792.26±830.48) ng/L and (248.88±93.72) ng/L]. TNF-α mRNA levels in low[(2.52±0.01)×103] and high dosage group[(2.48±0.02)×103] were both decreased as compared to control group[(6.17±0.19)×103]. The co-expression of TNF-α and COX-2 distributed widely in tubulointerstitial area in control group and only few in low dosage group. More TNF-α protein in CXB-treated group was detected than that in control group. Conclusion CXB can slow down disease progression in Han: SPRD rats with renal dysfunction through anti-inflammatory effect, including inhibition of COX-2 activity, blockage of 6-keto-PGF-1α and TXB 2 release, and down-regulation of COX-2 over expression by positive feedback.

Objective To investigate the expression of focal adhesion kinase(FAK) in epithelial-mesenchymal transition(EMT) of TGF-β1-stimulated HK-2 cells and the effect of FAK knockdown by small interfering RNA on EMT. Methods HK-2 cells were grown in DMEM-F12 medium supplemented by 10% fetal bovine serum(FBS). HK-2 cells were cultured in free serum medium for 24 h, then were stimulated by TGF-β1(10 μg/L). The expression of E-cadherin, α-SMA, FAK mRNA and protein were detected by RT-PCR, Western blot and immunofluorescence, respectively. The expression level of phosphorylated FAK-Tyr397 was detected by Western blot. HK-2 cells were transfected with 200 nmol/L FAK-siRNA or negative control siRNA using Lipofectamine 2000. Then the expression of E-cadherin, α-SMA, FAK protein was detected by Western blot. Results The expression of E-cadherin mRNA and protein was markedly decreased in HK-2 cells induced by TGF-β1, and the expression of α-SMA mRNA and protein was dramatically increased. Western blot analysis demonstrated that then protein levels of FAK and p-FAK(Tyr397) were progressively increased in a time-dependent manner in response to TGF-β1 treatment in HK-2 cells. When transfected with FAK-siRNA, the FAK mRNA and protein expression was markedly inhibited with 50% and 41%. Knockdown expression of FAK led to a severe blockage of TGF-β1-induced E-cadherin suppression and α-SMA induction. Conclusions The expression of FAK is up-regulated in HK-2 cells stimulated by TGF-β1. But the EMT induced by TGF-β1 in HK-2 cells is inhibited by FAK knockdown, which suggests that FAK plays an important role in TGF-β1-induced tubular EMT and renal fibrosis.

Objective To investigate the effect of PTH on the expression of CTGF in human renal proximal tubular epithelial cell line HK-2 and the role of nuclear factor kappa-B (NF-κB) signaling pathway. Methods The expression of CTGF mRNA and protein in HK-2 cells was measured by real time PCR and Western blot, respectively. The activity of NF-κB in HK-2 cells was measured by EMSA to investigate the mechanism by which PTH induced CTGF expression. The signaling pathway through which PTH produced biological effect was determined by using NF-κB signaling inhibitor PDTC. To assess the potential role of NF-κB activation in PTH-induced CTGF expression, HK-2 cells were transfected with CTGF luciferase reporter gene in the presence or absence of the PDTC added 12 h before PTH. Results A basal level of CTGF mRNA and protein expression was detected in HK-2 cells, with the maximal response to PTH at concentration of 10－10 mol/L and the best stimulating time at 72 hours. After exposure to PTH (10－10 mol/L) for 12 hours, the maximal level of luciferase activity was 1.96-fold of control. The NF-κB of nucleus was inactivated without PTH, while the activity of NF-κB significantly increased after exposed to PTH, with the maximal response to PTH at concentration of 10－10 mol/L and the best stimulating time at 30 minute. The NF-κB inhibitor PDTC reduced the increase of CTGF transcript levels in response to PTH stimulation. Similarly, CTGF mRNA and protein expression were decreased in PDTC-treated cells as compared with the untreated control cells(mRNA 0.33±0.05 vs 3.84±0.68, P＜0.05; protein 0.56±0.23 vs 3.76±0.54, P＜0.01). Conclusions PTH induces the expression of CTGF in HK-2 cells. This induction is dependent on NF-κB signaling pathway.

Objective To observe the expression and distribution of PTEN in renal epithelial-mesenchymal transition(EMT), and to investigate the effect of DJ-1 up-regulation on the expression and distribution of PTEN and the activation of PI3K-Akt signal pathway. Methods Human tubular epithelial cells (HKC cell line) were cultured with 10 μg/L TGF-β1 for 72 h. Protein expressions of PTEN, E-cadherin and α-SMA were measured by Western blot. RT-PCR was used to detect the expression of PTEN mRNA. To over express DJ-1, HKC cells were transfected with pEGFP-N1-DJ-1 via lipofectamine 2000 to induce up-regulation of DJ-1. The efficiency of transfection was examined by fluorescence microscope and Western blot. The expressions of DJ-1, PTEN, p-Akt and Akt in the transfected cells were detected by Western blot, and PTEN mRNA was detected by RT-PCR. The intracellular distribution of PTEN in normal HKC cells, cells stimulated by TGF-β1 and cells transfected with pEGFP-N1-DJ-1 was observed by confocal microscope. Results Normal HKC cells expressed PTEN, E-cadherin, but almost did not express α-SMA. The expressions of PTEN protein, PTEN mRNA and E-cadherin in cells stimulated by TGF-β1 were less as compared to normal cells (P<0.05), while α-SMA expression was increased (P<0.05). The effenciency of green fluorescence was more than 80% in transfected cells. In the DJ-1 transfectants, the expressions of PTEN and PTEN mRNA were suppressed, but p-Akt expression was up-regulated as compared to normal cells. In normal HKC cells, PTEN distributed both in cytoplasm and nucleus. In cells stimulated by TGF-β1, cytoplasmic PTEN was completely lost while nuclear PTEN was increased slightly. In the DJ-1 transfectants, only the nuclear PTEN was observed which was similar to the cells stimulated by TGF-β1. Conclusion In renal interstitial fibrosis, the over-expression of DJ-1 can suppress PTEN expression and activate PI3K-Akt signal pathway.

Objective To observe the effects of megsin gene transfection on mesangial cell proliferation and expression of matrix metalloproteinase-2(MMP-2), tissue inhibitor of metalloproteinase-2（TIMP-2） and type Ⅳ collagen under high glucose concentration , and to investigate the relationship between megsin and mesangial cell proliferation and extracellular matrix metabolism. Methods Mouse glomerular mesangial cells were cultured in high glucose medium, then cell proliferation was measured by MTT at 12, 24 and 48 h respectively after culture. Protein levels of megsin, MMP-2, TIMP-2 in mesangial cells were detected by Western blot. Concentration of type Ⅳcollagen in supernatant of mesangial cells was measured by radioimmunochemistry. Results Under high glucose concentration, megsin and TIMP-2 expression were increased, MMP-2 expression was decreased, the concentration of type Ⅳ collagen in the cellular supernatant was increased, and mesangial cell proliferation was enhanced. After megsin gene transfection, the above changes were more significant. Conclusion Megsin gene induces mesangial cell proliferation and inhibits matrix degradation through TIMP-2 up-regulation and MMP-2 down-regulation, which is probably one of the mechanisms of accelerating glomerulosclerosis.