Fibroblast growth factor 21 and protein energy wasting in hemodialysis patients

Abstract

Introduction: Protein energy wasting (PEW) is the most important risk factor for morbidity and mortality in hemodialysis patients. Inadequate dietary protein intake is a frequent cause of PEW. Recent studies have identified fibroblast growth factor 21 (FGF21) as an endocrine protein sensor. This study aims to investigate the potential of FGF21 as a biomarker for protein intake and PEW and to investigate intradialytic FGF21 changes. Methods: Plasma FGF21 was measured using an enzyme-linked immunoassay. Complete intradialytic dialysate and interdialytic urinary collections were used to calculate 24-h urea excretion and protein intake. Muscle mass was assessed using the creatinine excretion rate and fatigue was assessed using the Short Form 36 and the Checklist Individual Strength. Results: Out of 59 hemodialysis patients (65 ± 15 years, 63% male), 39 patients had a low protein intake, defined as a protein intake less than 0.9 g/kg/24-h. Patients with a low protein intake had nearly twofold higher plasma FGF21 compared to those with an adequate protein intake (FGF21 1370 [795e4034] pg/mL versus 709 [405e1077] pg/mL;P < 0.001). Higher plasma FGF21 was associated with higher odds of low protein intake (Odds Ratio: 3.18 [1.62e7.95] per doubling of FGF21; P ¼ 0.004), independent of potential confounders. Higher plasma FGF21 was also associated with lower muscle mass

Elevated serum FGF21 is an independent predictor for adverse events in hemodialysis patients from two large centers: a prospective cohort study

“…found that there was a slight increase in circulating FGF21 concentration after hemodialysis, which was statistically significance [ 25 , 27 ]. A recent study also compared the FGF21 concentration at the start and end of HD and found that the plasma FGF21 concentration increased by 29% after hemodialysis, while hemoglobin, hematocrit, and albumin increased by only 8%, 6%, and 10% respectively [ 27 ]. Therefore, the increase in plasma FGF21 level exceeded the expected concentration during HD.…”

Urinary Endotrophin and Long-term Outcomes in Kidney Transplant Recipients

“…Outliers were defined as values deviating >2 SD from the mean of the log 2 24-h urinary endotrophin excretion. 27 Furthermore, since urinary endotrophin has been shown to reflect the degree of fibrosis in nontransplant patients with kidney disease, 14,15 we reevaluated the association of 24-h urinary endotrophin excretion with study endpoints after excluding KTR with recurrent kidney disease as the cause of graft failure. Next to that, we repeated the Cox regression analyses with urinary endotrophin concentration and urinary endotrophin concentration indexed for creatinine (urinary endotrophin/creatinine ratio).…”

Fibroblast Growth Factor 21: A Fascinating Perspective on the Regulation of Muscle Metabolism

“…More importantly, FGF21 improves the proportion of oxidized muscle fibers in skeletal muscle, alleviates oxidative stress damage to skeletal muscle mitochondria, reduces the generation of skeletal muscle myopathy, and better maintains muscle metabolic homeostasis [18,55,56]. However, it should be noted that many studies established the sensitivity characteristic of FGF21 for protein content, and the production of FGF21 is induced when protein intake is reduced or the amount of synthesis is insufficient, likely resulting in decreases in weight, muscle mass, and vitality [47,57,58].…”

“…[18,55,56]. However, it should be noted that many studies established the sensitivity characteristic of FGF21 for protein content, and the production of FGF21 is induced when protein intake is reduced or the amount of synthesis is insufficient, likely resulting in decreases in weight, muscle mass, and vitality [47,57,58]. For example, higher circulating FGF21 may be associated with sarcopenia and poor muscle mass in elderly individuals [59].…”