Objective To observe the effect of L-carnitine on plasma soluble tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) protein in maintenance hemodialysis (MHD) patients.Methods Forty-six cases of MHD patients were enrolled as MHD group,and 40 cases of the same period healthy subjects were enrolled as control group.The levels of plasma sTWEAK protein,high-sensitivity C-reactive protein (hs-CRP),interleukin (IL)-6 and insulin-like growth factor (IGF)-1 were measured by enzyme-linked immunosorbent assay (ELISA).Twenty-six MHD patients with the levels of sTWEAK protein higher than control group mean value as treatment group,were treated for L-carnitine 1.0 g in 0.9％ sodium chloride solution 20 ml after hemodialysis by intravenous injection one time per week.Twenty MHD patients with the levels of sTWEAK protein lower than or equal to control group mean value as non-treatment group.The changes of sTWEAK protein,IGF-1,grip strength and protein energy waisting (PEW) were observed after 3 months treatment.Results The levels of plasma sTWEAK protein,IL-6 and hs-CRP in MHD group were higher than those in control group [(464 ± 102) ng/L vs.(346 ± 159) ng/L,(986.54 ± 123.12) ng/L vs.(407.12 ± 180.25) ng/L,(18.8 ± 2.9) mg/L vs.(1.0 ± 1.2) mg/L],there were significant differences (P＜ 0.05).Compared with non-treatment group,the levels of plasma sTWEAK protein,IL-6 and hs-CRP in treatment group after treatment of 3 months were decreased [(126 ± 92) ng/L vs.(243 ± 103) ng/L,(799.45 ± 105.34) ng/L vs.(966.04 ± 113.11) ng/L,(13.7 ± 1.9) mg/L vs.(26.8 ± 2.8) mg/L],IGF-1 was increased,grip strength was increased,PEW was improved,there were significant differences (P ＜ 0.01 or ＜ 0.05).The body mass index in treatment group was more than that in non-treatment group,but there was no significant difference (P ＞ 0.05).Conclusions L-carnitine can reduce the levels of plasma sTWEAK protein in MHD patients,reduce inflammatory reaction,improve the levels of IGF-1,increase strength,improve the PEW.

Objective To investigate the relationship between soluble tumor necrosis factor-like weak inducer of apoptosis levels (sTWEAK) and cardiovascular events in patients with maintenance hemodialysis (MHD).Methods A prospective cohort study was conducted in 64 MHD patients(MHD group).The plasma level of sTWEAK was measured by enzyme-linked immunosorbent assay,N-terminal pro-brain natriuretic peptide (NT-proBNP) and high-sensitive C-reactive protein (hs-CRP) levels were measured by enzyme-linked immunofluorescence method,left ventricular end-diastolic diameter (LVEDd),left ventricular posterior wall thickness (LVPWT),end-diastolic ventricular septal thickness (IVST),left ventricular ejection fraction (LVEF) was determined by echocardiography.The general situation,clinical indicators and occurrence of cardiovascular events of MHD patients were recorded and followed up for 2 years.Fifty healthy people were selected as control group.Results The plasma level of sTWEAK was higher in MHD group than that in control group [(589 ± 122) ng/L vs.(346 ± 127) ng/L],and there was significant difference (P＜ 0.01).During the follow-up period,12 patients underwent cardiovascular events(3 patients died).The plasma level of sTWEAK in cardiovascular event patients was significantly higher than that in non-cardiovascular event patients (695 ng/L vs.458 ng/L),and there was significant difference (P ＜ 0.01).The plasma level of sTWEAK was positively correlated with NT-proBNP in MHD patients(r =0.698,P ＜ 0.05).Logistic repression analysis showed that sTWEAK was the predictor of cardiovascular events of MHD patients.Conclusion The plasma level of sTWEAK probably predicts the ocurrence of cardiovascular event in MHD patients.

Objective To investigate the effect of klotho on the human vein umbilical endothelial cells (HUVECs) injury induced by indoxyl sulfate (IS) and to explore its mechanism and the role of endoplasmic reticulum stress (ERS) in this process.Methods (1) The cell vitalities of HUVECs incubated with different concentration of IS (5,25,50 mg/L) for 48 h and with 50 mg/L IS fordifferent time points (12,24,48 h) were measured by CCK-8 assay.(2) HUVECs were incubated with 50 mg/L IS and different concentration of klotho (0,1,10,100 μg/L) for 48 h and their cell viabilities were measured by CCK-8 assay.(3) HUVECs were divided into four groups:control group,IS group (50mg/L IS),klotho group (50 mg/L IS+ 100 μg/L klotho) and Compound C group (50 mg/L IS+100 μg/L klotho+ 10 μmol/L Compound C).The cell vitality and the apoptosis of HUVECs were evaluated by CCK-8 assay and flow cytometry,respectively.The mRNA and protein expressions of GRP78 and CHOP were measured by real-time PCR and Western blotting.The phosphorylation level of AMPK was tested by Western blotting.Results IS inhibited cell vitality in the time-dependent and concentration-dependent manner.The cell viability of HUVECs with 50 mg/L IS was lower than normal control (P＜0.05).The inhibited cell vitality induced by IS was partly restored by klotho in concentration-dependent manner.The cell viability was higher in 100 μg/L klotho+50 mg/L IS group than 50 mg/L IS group (P ＜ 0.05).Compared with control group,the expressions of GRP78 and CHOP and cell apoptosis increased,however,the level of phosphorylated AMPK (p-AMPK) decreased in IS group (all P ＜ 0.05).Compared with IS group,the expressions of GRP78 and CHOP and cell apoptosis decreased and the level of p-AMPK increased in klotho group (all P ＜ 0.05).Furthermore,the above effects of klotho could be partly blocked by Compound C.The above indexes showed statistical differences between Compound C group and klotho group.Conclusions IS can inhibit the HUVECs cell vitality,and induce ERS and cell apoptosis.Klotho protein could antagonize the above effects,probably through activating AMPK pathway and reducing ERS-mediated cell apoptosis.