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Objective:To investigate the etiology, clinicopathological changes and genetic variation characteristics of familial juvenile hyperuricemia nephropathy (FJHN) through pedigree investigation and gene test conducted on a patient with FJHN.Methods:Clinical data of the proband family members were collected, routine pathological examination of the proband kidney tissue was conducted, and the expression of the Uromodulin (UMOD) protein in the proband kidney tissue was detected by immunofluorescence staining. Peripheral blood specimens of proband and their relatives were collected, and gene sequencing analysis related to urinary system diseases including UMOD was performed by double-stranded DNA probe gene capture and high-throughput sequencing. Results:Seven family members in the family were involved and the inheritance method was consistent with autosomal dominant inheritance. Among the seven affected individuals only a 3-year-old child didn't show any clinical abnormalities. All of the remaining six patients had hyperuricemia accompanied with renal dysfunction and three of them were end-stage renal disease and two of them died of uremia. Proband renal pathological results showed chronic tubulointerstitial lesions and focal glomerular sclerosis with no obvious deposition of immune complexes. Immunofluorescent staining showed that strong positive signals of UMOD protein accumulated in the tubular epithelial cells, which was very specific and could be used to differentiate FJHN from other interstial nephritis. A total of four patients including the proband were tested and all had found heterozygous mutation c.377G>A of UMOD gene, a new missense mutation located on exon 3. Conclusion:Involved patients in this family present a typical autosomal dominant inheritance pattern, clinically manifested as hyperuricemia with early renal function impairment, renal pathology manifested as non-immune complex-mediated glomerular sclerosis and renal interstitial fibrosis, and there is abnormal accumulation of UMOD protein in renal tubular epithelial cells. Genetic testing shows a new gene locus mutation c.377G>A, confirming the diagnosis of FJHN. Patients with unexplained hyperuricemia and characteristic pathological changes should undergo renal tissue fluorescent staining of UMOD protein, which may be a simple and feasible method to detect the abnormality of UMOD protein.
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Objective To investigate the association of low serum total bilirubin (TBIL) levelwith all?cause mortality and cardiovascular mortality in peritoneal dialysis patients. Methods As a single ? center, retrospective, cohort study, all the patients who underwent peritoneal dialysis catheterization in the Department of Nephrology, the First Affiliated Hospital of Sun Yat?sen University and started peritoneal dialysis for more than 3 months from January 1, 2006 to December 31, 2010 were included. Demographics, baseline clinical and laboratory test results were collected. All patients were followed up until December 31, 2012. Patients were divided into 4 groups according to their baseline serum TBIL levels (interquartile range). Kaplan?Meier method was used to compare the survival rate of each group. Cox regression model was used to analyze the association of TBIL with all?cause mortality and cardiovascular mortality. Logistic regression was used to analyze the influencing factors of low TBIL level. Results A total of 880 peritoneal dialysis patients with baseline TBIL data were enrolled in this study, with age of (48.0 ± 15.4) years old, among whom 59.0％ were male. Median TBIL was 4.5 μmol/L and interquartile range was 3.4?5.8 μmol/L. The comparison between TBIL quartile groups showed that the difference in proportion of diabetics, Charlson comorbidity index, hemoglobin, serum albumin, serum calcium, intact parathyroid hormone, urea nitrogen, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) was statistically significant (all P<0.05), while the difference in body mass index (BMI), estimated glomerular filtration rate, serum creatinine, urea nitrogen, uric acid and phosphorus was not statistically significant. After a median follow?up of 31 months, 194 patients died, 104 of which were cardiovascular deaths. Kaplan?Meier curves showed higher all?cause mortality in patients with TBIL≤3.4 μmol/L (Q1 group) (P=0.032) and there was no statistical difference in the cardiovascular mortality among different groups. After adjusting for biochemical indicators such as demographics, comorbidities, and liver function, taking baseline TBIL Q2 level (3.4<TBIL≤4.5 μmol/L) as a reference, the hazard ratio for all?cause death in patients with TBIL≤3.4 μmol/L was 1.702 (95％CI 1.093-2.650, P=0.019), and the hazard ratio for cardiovascular death was 1.760 (95％CI 0.960-3.227, P=0.068). Multiple logistic regression analysis results showed that diabetes (OR=1.065, 95％CI 1.010-1.122, P=0.019) and high BMI (OR=1.838, 95％CI 1.056-3.197, P=0.031) were risk factors for baseline serum TBIL≤3.4 μmol/L. However, high hemoglobin (OR=0.990, 95％CI 0.982-0.998, P=0.011), high serum albumin (OR=0.950, 95％CI 0.916-0.985, P=0.006) and high ALT (OR=0.998, 95％CI 0.976-0.999, P=0.036) were the protective factors for patients with baseline serum TBIL≤3.4 μmol/L. Conclusion Baseline serum TBIL≤3.4 μmol/L in peritoneal dialysis patients is independently associated with all?cause mortality, and is not significantly associated with cardiovascular mortality; and baseline serum TBIL≤3.4 μmol/L occurred is associated with diabetes, high body mass index, low levels of hemoglobin, serum albumin and ALT.
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Objective To investigate the effects of peptide-binding domain (PBD) of heat shock protein (HSP) 72 on epithelial to mesenchymal transition (EMT) in rat renal tubular epithelial cells.Methods The expressions of wild-type HSP72,mutant of HSP72 lacking peptide binding domain (HSP72-△PBD) and HSP72-PBD were induced by plasmid transfection.NRK-52E ceils were stimulated by TGF-β1 for 48 h.The expressions of α-smooth muscle actin (α-SMA),E-cadherin,HSP72 and Smad3/p-Smad3 were detected by Western blot and immunofluorescence.Results After NRK-52E cells were stimulated by TGF-β 1 (10 μg/L) for 48 h,the expression of α-SMA was increased and the protein level of E-cadherin was decreased.Western blotting and immunofluorescence showed that over-expression of both HSP72 and PBD inhibited TGF-β1-induced up-regulation of protein α-SMA expression,down-regulation of protein E-cadherin.However,overexpression of HSP72-△PBD did not change the protein level of E-cadherin and α-SMA.In addition,over-expression of HSP72 and PBD significantly inhibited the phosphorylation of Smad3.Conclusion Inhibition of Smad3 activation and EMT by HSP72 is associated with the function of PBD.
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Objecfive To investigate the change of V-ATPase B subunits on epithelial to mesenchymal transition (EMT)in rat renal tubular epithelial cells (NRK52E) stimulated by transforming growth factor β1 (TGF-β1). Methods NRK52E cells were stimulated by TGF-β1 (10 μg/L)for O h(control),12 h,24 h,48 h,72 h after sefrum-free culture for 24 h.The mRNA and protein expression of E-cadherin,α-SMA,B2 and B1 subunits of V-ATPase were detected by real-time PCR,Western blotting and immunofluorescence. Results After stimulated by TGF-β1 (10 μg/L)for 48 h,the expression of α-SMA was markedly increased(P<0.05),but the expression of E-cadherin was dramatically decreased(P<0.05).Meanwhile,the expressions of V-ATPase subunit B2 was significantly increased (P<0.05).However,the B1 subunit distributed rarely in NRK 52E cells,and did not increase after TGF-β1 stimulation.Double-label immunofluoerscence staining also showed that the V-ATPase B2 subunit was increased in the cytosol.tending to accumulate to the cell membrane after TGF-β1 stimulation. Conclusions The main isoform of V-ATPase distributed in NRK52E cells is B2 subunit.B2 subunit is increased alone with TGF-β1-induced EMT.It may suggest that V-ATPase B2 subunit may play a potential role in TGF-β1-induced tubular EMT and renal fibrosis.
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Objective To explore the effect of Numb on tubular epithelial-to-mesenchymal transition (EMT) in rat proximal epithelial cells. Methods NRK52E cells were treated with different concentrations of recombinant human transforming growth factor-β1 (TGF-β1) (0, 1, 5, 10, 15, 20 μg/L) for 48 h or 10 μg/L TGF-β1 for different times (0, 24, 48, 72 h) in vitro. The expressions of E-cadherin, a-smooth muscle actin(α-SMA) and Numb in NRK 52E cells were detected by RT-PCR, Western blot and immunofluorescence staining. Meanwhile Numb siRNA oligo was transfected into NRK 52E cells with lipofectamine before TGF-β1 treatment, then Western blot was applied to detect the protein expression of E-cadherin, α-SMA and Numb in NRK52E cells. Results TGF-β1 could induce EMT in NRK52E cells in dose- and time-dependent manner. During the progress of TGF-β1-induced EMT, the protein expression of Numb in 5, 10, 15, 20 μg/L group was 1.33 folds (P=0.024), 1.39 folds (P=0.035), 1.45 folds (P=0.025), 1.51 folds (P=0.000) respectively as compared to 0 μg/L group. Likewise, the protein and mRNA expression of Numb in 24 h, 48 h, 72 h group was 1.48 folds (P=0.046) and 1.56 folds (P=0.012), 1.54 folds (P=0.011) and 1.82 folds (P=0.008), 1.79 folds (P=0.028) and 1.82 folds (P=0.002) respectively as compared to 0 h group. Moreover, large amount of Numb was accumulated in the cytoplasm. Down-regulation of Numb expression by siRNA transfection did not influence the basal expression of E-cadherin and α-SMA in NRK 52E cells, but attenuated the progression of EMT in NRK52E cells induced by TGF-β1. The up-regulation of α-SMA protein was reduced to 18.1% (P=0.004) while the down-regulation of E-cadherin protein was reversed to 2.19 folds (P=0.004). Conclusion Numb can promote EMT in rat proximal epithelial cells.
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Objective To investigate the effects of angiotensin Ⅱ (Ang Ⅱ) on the expression of TLR4 and its role in lipopolysaccharide (LPS)-induced NF-κB activation and CD40 expression in rat peritoneal mesothelial cells (RPMCs). Methods RPMCs were harvested from Spragne-Dawley rat peritoneal cavity and maintained under defined in vitro condition. The cells were treated with Ang Ⅱ at different concentrations (10-9, 10-8, 10-7, 10-6 mol/L) and exposed to Ang Ⅱ (10-7 mol/L) for different times (1, 2, 4, 8, 12, 24, 48 h for mRNA and 6, 12, 24, 36, 48 h for protein, respectively). Meanwhile, the influence of AT1 receptor antagonist (AT1R, losartan, 10-5 mol/L) and AT2 receptor blocker (AT2R, PD123177, 10-5 mol/L) on the TLR4 induced by Ang Ⅱ was observed. After synchronization for 24 hours, the cells were randomly assigned to four groups: the control group, the Ang Ⅱ (10-7 tool/L) group, the LPS (1 mg/L) group, the Ang Ⅱ (10-7 mol/L) plus LPS (1 mg/L) group, which were used to investigate the effects of Ang Ⅱ on the NF-κB activation and CD40 expression induced by LPS. The mRNA expression of TLR4 and CD40 was measured by RT-PCR and the protein abundance of TLR4, NF-κB p65, phospho-p65, IKBα and phospho-IκBα were analyzed by Western blot. Immunofluorescence was performed to determine the subcellular localization of p65 subunit of NF-κB. Results (1) Treatment of RPMCs with Ang Ⅱ resulted in a concentration-dependent increase in the expression of TLR4. Ang Ⅱ at 10-9, 10-8, 10-7 and 10-6 mol/L increased TLR4 mRNA expression by 70.5%, 89.5%, 102.9%, and 121.9%, respectively and protein expression by 12.1%, 27.7%, 51.2%, and 41.6%, respectively (P<0.01). Treatment of RPMCs with 10-7 mol/L Ang Ⅱ resulted in a time-dependent increase in the expression of TLR4, with the peak of mRNA expression at 8 and 12 h (P<0.01) and the protein expression at 12 and 24 h (P<0.01). (2) Losartan antagonized Ang Ⅱ-stimulated expression of TLR4 by 33.5% (P<0.05), PD123177 had no such effect (P0.05). (3) Treatment of RPMCs with LPS (1 mg/L) for 60 rain significantly increased the ratio of phospho-IκBα to IκBα by 362.6% (P< 0.01) , phospho-p65 to p65 by 67.4% (P<0.05), and LPS (1 mg/L) for 4 h significantly increased the expression of CD40 mRNA by 299.9% (P<0.01) compared to the control group. In comparison to the LPS (1 mg/L) group, preincubation of RPMCs with AngⅡ (10-7 mol/L) for 24 h then treated with LPS (1 mg/L) for 60 rain significantly increased the ratio of phospho-IκBα to IκBα by 49.1% (P<0.01), phospho-p65 to p65 by 29.3%(P<0.05), and LPS (1 mg/L) for 4 h significantly increased the expression of CD40 mRNA by 56.8%(P<0.01). (4) The p65 subunit of NF-κB was dominantly distributed in the cytoplasm in the control and Ang Ⅱ group. Following exposure to LPS for 60 min, p65 subunit labeling was upregulated and translocated into the nuclei. A significantly increased nuclear staining of p65 in ceils treated with Ang Ⅱ plus LPS were observed. Conclusions Ang Ⅱ induces the expression of TLR4 in dose- and time-dependent manner in RPMCs, resulting in enhanced NF-κB signaling and induction of CD40 expression, Locally produced Ang Ⅱ in the peritoneum may play an amplified role in LPS-induced peritoneal inflammation.