RESUMO
Objective To study the association of serum L-kynurenine changes with nutritional status and vascular stiffness in maintenance hemodialysis (MHD) patients. Methods Twenty gender- and age-matched healthy volunteers (healthy group) and 40 MHD patients,including 20 cases with α-keto aicd(α-keto acid group)and 20 cases without α-keto aicd(non-α-keto acid group)were enrolled in the study.Serum L-kynurenine was measured by high performance liquid chromatography.C-reactive protein (CRP)and interleukin 6 (IL-6)were detected.Subjective global assessment(SGA)and malnutrition inflammation score(MIS)were applied to evaluate the nutritional status.Pulse wave velocity(PWV)was used to evaluate arterial stiffness for both groups of MHD patients. Results Serum L-kynurenine was significantly higher in MHD patients than that in healthy subjects[(3.20±1.12)μmol/L vs (1.74±0.27)μmol/L,P0.05].IL-6 was significantly higher in MHD patients as compared to healthy subjects[(6.45±3.78)ng/L vs(1.38±1.59)ng/L,P<0.01],while such difference was found between α-keto aicd group and non-α-keto aicd group[(3.37±0.82)ng/L vs (9.62±2.48)ng/L,P<0.051.There was no difference of CRP concentration between two MHD groups.As compared to non-α-keto acid group,higher SGA score(26.00±1.75 vs 22.67±2.61,P=0.001),lower MIS score(5.82±2.27 vs 10.00±2.62,P=0.002),lower left side PWV[(21.11±8.21)m/s vs(24.57±5.45)m/s,P=0.244]and lower right side PWV[(19.27±3.22)m/s vs (24.19±5.41)m/s,P=0.015]were observed in α-keto aicd group.Pearson analysis showed positive correlation between serum L-kynurenine and IL-6(r=0.352,P=0.011)and negative correlation between L-kynurenine and pre-dialysis Scr(r=-0.412,P=0.019). Conclusions Inflammation is common in MHD patients.Tryptophan degeneration product L-kynurenine may indicate inflammation status.α-keto acid improves nutritional status,anemia and arterial stiffness maybe through the alleviation of inflammation in MHD patients.
RESUMO
Objective To investigate the expression of parathyroid hormone/parathyroid hormone relative protein (PTH/PTHrP) receptor of osteoblast in hemodialysis patients and the effects of calcium channel blocker(CCB) and calcitriol on it. Methods Twenty-one patients on HD were randomly divided into three groups. Six patients were treated with CCB for 8 weeks. Seven patients were given calcitriol for 8 weeks. The rest 8 cases did not take either CCB or calcitriol. Five healthy people were selected as control group. The serum levels of iPTH, BUN, Scr, calcium and phosphorus were measured. The osteoblast was prepared from cultured bone marrow. PTH receptor mRNA expression was detected by semi-quantitive RT-PCR. Results The level of PTH/PTHrP receptor mRNA decreased significantly in patients on HD as compared with control group, and increased in patients with CCB. In calcitriol treated group, and PTH/PTHrP receptor was obviously down-regulated with larger dose of calcitriol(0. 75?g/d), and up-regulated with low dose(0. 25?g/d) . Conclusion Expression of PTH/PTHrP receptor down-regulates in osteoblast of HD patients. CCB can up-regulate the expression of PTH/PTHrP receptor. A large dose of calcitriol may decrease iPTH level and down-regulate PTH/PTHrP receptor expression.