AIM:To investigate the regulatory role of nuclear factor κB (NF-κB) in the expression of interleukin-6 in mesangial cells (MC) induced by interleukin-1β.METHODS:Activation of NF-κB was measured by electrophoresis mobility shift assay (EMSA). RT/PCR and ELISA were used to detect IL-6 mRNA expression and IL-6 production, respectively.RESULTS:rhIL-1β could rapidly stimulate the activation of NF-κB in MC, and increase the expression of IL-6 mRNA and protein. PDTC, one of the inhibitor of NF-κB， could inhibit the expression of IL-6 in mRNA and protein in MC stimulated by rhIL-1β.CONCLUSION:IL-6 expression induced by IL-1β may be regulated by NF-κB in MC, NF-κB may modulate the immune-inflammatory reaction in glomerular disease.

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.

OBJECTIVESWe identified the long QT syndrome (LQTS) patients, and detected the potential risk of LQTS in family members by using genetic testing and electrophysiological analysis, which helped provide clinical evaluation and appropriate treatment.

METHODSDetailed clinical characteristics and familiar history were obtained from the whole family members of an idiopathic pediatric LQTS patient. Two hundred healthy subjects with the same ethnic background were recruited as controls. The entire coding sequences of three candidate genes including KCNQ1, KCNH2 and SCN5A were screened for mutations in the proband. The function of the mutation was then explored by whole-cell patch clamp techniques, and the genetic testing and risk assessment of the family members were performed.

RESULTSThe proband was clinically preliminary diagnosed as LQTS by 12-lead electrocardiogram. On the third day of metoprolol intake (25 mg, bid), she died suddenly at lunch. One heterozygous missense mutation (SCN5A-V411M) was identified in this proband, but the mutation was absent in 200 healthy subjects. The electrophysiological analysis indicated that SCN5A-V411M significantly increased the peak current density ((230.8 ± 27.6)pA/pF vs. (101.2 ± 10.9)pA/pF, n=10, P<0.01) and the late sodium current ((156.6 ± 13.6)pA/pF vs. (95.9 ± 7.9)pA/pF, n=12, P<0.01) of sodium channel compared to wide type. The enhanced sodium channel activation with a negative shift in the peak I-V relationship was significantly higher by -50 mV than wide type (85.0%± 7.4% vs. 41.5% ± 2.6%, P<0.01), while the steady-state inactivation curves remained unchanged. Additionally, mother and grandmother of the proband were the silent mutation carriers with no symptoms, who needed the appropriate clinical assessment and follow-up. The proband's twin sister and aunt died of sudden infant death syndrome.

CONCLUSIONSWe firstly reported a heterozygote missense mutation (SCN5A-V411M) in this Chinese family. V411M induced "gain of function" of sodium channel and formed the basis of type-3 LQTS. Genetic testing could help to increase the diagnostic accuracy, and facilitate clinical assessment and appropriate therapy to prevent sudden cardiac death of individuals with SCN5A-V411M mutation.

Cardiac Conduction System Disease ; Death, Sudden, Cardiac ; Genetic Testing ; Humans ; Incidence ; Long QT Syndrome ; Mutation ; Patch-Clamp Techniques