Acetate-free biofiltration to remove fibroblast growth factor 23 in hemodialysis patients: a pilot study

Indole-3-acetic acid correlates with monocyte-to-high-density lipoprotein (HDL) ratio (MHR) in chronic kidney disease patients

PURPOSE

Indole-3-acetic acid is a protein-bound indolic uremic toxin deriving from tryptophan metabolism. Increased levels are associated with higher thrombotic risk and both cardiovascular and all-cause mortality. An emerging biomarker of cardiovascular disease is the monocyte-to-high-density lipoprotein ratio (MHR). The main purpose of this study was to investigate the association of indole-3-acetic acid with MHR and other markers of cardiovascular risk in patients with chronic kidney disease (CKD).

METHODS

We enrolled 61 non-dialysis CKD patients and 6 dialysis patients. Indole-3-acetic acid levels were measured with ELISA technique.

RESULTS

In the whole cohort of 67 patients, indole-3-acetic acid was directly related to Ca × P (ρ = 0.256; P = 0.0365) and MHR (ρ = 0.321; P = 0.0082). In the 40 patients with previous cardiovascular events, indole-3-acetic acid correlated with uric acid (r = 0.3952; P = 0.0116) and MHR (ρ = 0.380; P = 0.0157). MHR was related with fibrinogen (ρ = 0.426; P = 0.0010), arterial hypertension (ρ = 0.274; P = 0.0251), C-reactive protein (ρ = 0.332; P = 0.0061), gender (ρ = - 0.375; P = 0.0017; 0 = male, 1 = female), and CKD stage (ρ = 0.260; P = 0.0337). A multiple regression analysis suggested that indole-3-acetic acid might be an independent predictor of MHR.

CONCLUSION

This study shows a significant association between indole-3-acetic acid and MHR. Prospective studies are required to evaluate if decreasing indole-3-acetic acid concentrations may reduce MHR levels and cardiovascular events and improve clinical outcomes.

Fibroblast growth factor 23: are we ready to use it in clinical practice?

Patients with chronic kidney disease (CKD) have a greatly enhanced risk of cardiovascular morbidity and mortality. Over the past decade it has come clear that a disturbed calcium-phosphate metabolism, with Fibroblast Growth Factor-23 as a key hormone, is partly accountable for this enhanced risk. Numerous studies have been performed unravelling FGF23s actions and its association with clinical conditions. As FGF23 is strongly associated with adverse outcome it may be a promising biomarker for risk prediction or, even more important, targeting FGF23 may be a strategy to improve patient outcome. This review elaborates on the clinical usefulness of FGF23 measurement. Firstly it discusses the reliability of the FGF23 measurement. Secondly, it evaluates whether FGF23 measurement may lead to improved patient risk classification. Finally, and possibly most importantly, this review evaluates if lowering of FGF23 should be a target for therapy. For this, the review discusses the current evidence indicating that FGF23 may be in the causal pathway to cardiovascular pathology, provides an overview of strategies to lower FGF23 levels and discusses the current evidence concerning the benefit of lowering FGF23.

Change in FGF23 concentration over time and its association with all-cause mortality in patients treated with haemodialysis or haemodiafiltration

Background

Previous studies in patients on haemodialysis (HD) have shown an association of fibroblast growth factor 23 (FGF23) with all-cause mortality. As of yet, the result of FGF23 lowering on mortality is unknown in this population.

Methods

FGF23 was measured in a subset of 404 patients from the Dutch CONvective TRansport STudy (CONTRAST study) [a randomized trial in prevalent dialysis patients comparing HD and haemodiafiltration (HDF) with clinical outcome] at baseline and Months 6 and 12. A substantial decline of FGF23 change over time was anticipated in patients randomized to HDF since HDF induces higher dialytic clearance of FGF23. The associations of both baseline FGF23 and 6-months change in FGF23 with all-cause mortality were analysed. In addition, the difference in FGF23 change between HD and HDF was explored. Furthermore, the role of dialysis modality in the association between FGF23 change and outcome was analysed.

Results

No association was observed between quartiles of baseline FGF23 and all-cause mortality. Over 6 months, FGF23 declined in patients on HDF, whereas FGF23 remained stable in patients on HD. A decrease in FGF23 was not associated with improved survival compared with a stable FGF23 concentration. However, increasing FGF23 was associated with a significantly higher mortality risk, both in crude and fully adjusted models [hazard ratio 2.01 (95% confidence interval 1.30–3.09)].

Conclusion

Whereas no association between a single value of FGF23 and all-cause mortality was found, increasing FGF23 concentrations did identify patients at risk for mortality. Since lowering FGF23 did not improve outcome, this study found no argument for therapeutically lowering FGF23.

Effects of recombinant human growth hormone on protein malnutrition and IGF-1 and IL-2 gene expression levels in chronic nephrotic syndrome

The aim of the study was to investigate the effects of recombinant human growth hormone on protein malnutrition and insulin-like growth factor-1 (IGF-1) and interleukin-2 (IL-2) gene expressions in chronic nephrotic syndrome. Eighty patients with chronic nephrotic syndrome were admitted to our hospital. The patients were included in the study period from January 2015 to December 2016 and were divided into two groups (40 cases in each group) according to the random number method. All the patients enrolled received symptomatic and supportive treatment. The observation group was injected subcutaneously with recombinant human growth hormone, while the control group was treated with Shenyankangfu tablets. The recovery time of the clinical symptoms, change in serum protein, caloric intake and protein metabolism after intervention were compared between the two groups. Changes in serum cystatin C, IGF-1 and IL-2 before intervention, and at 1 week, 1 month and 3 months after intervention were detected, and the adverse reactions in the two groups were observed during the treatment. After intervention, the improvement time of proteinuria, hypoproteinemia, edema and hyperlipidemia in the observation group was significantly shorter than that in the control group (P<0.05). The expression of transferrin, pre-albumin, albumin and total protein in the observation group was significantly superior increased compared to those in the observation group prior to intervention and the control group after intervention (P<0.05). In addition the caloric intake, protein intake and urea nitrogen survival rate in the observation group were significantly superior to those in the observation group prior to intervention and the control group after intervention (P<0.05). At 1 week, 1 month and 3 months after intervention, the levels of serum cystatin C, IGF-1 and IL-2 in the observation group were markedly obviously lower than those in the control group during the same period (P<0.05). The total proportion of allergy, systemic pruritus, nausea and vomiting, abdominal distension and abdominal pain in the observation group was obviously lower than that in the control group (P<0.05). Compared with the traditional Chinese medicine Shenyankangfu tablets applied in the control group, the recombinant human growth hormone used for patients with chronic nephrotic syndrome can improve the clinical symptoms more quickly, regulate the protein metabolism and reduce the inflammatory response in the body, which also has fewer adverse reactions and higher safety.