Response of fibroblast growth factor 21 to meal intake and insulin infusion in patients on maintenance haemodialysis.

OBJECTIVE

To investigate the response of serum fibroblast growth factor 21 (FGF21) to a meal and to insulin infusion in haemodialysis (HD) patients.

DESIGN AND PATIENTS

Meal study: in a crossover design, 12 nondiabetic HD patients were randomly assigned to: (1) a non-HD day with one meal served, (2) a HD day with one meal served during HD and (3) a HD day with two meals served during and after HD, respectively. Twelve healthy controls participated in an experiment identical to the non-HD day. Insulin infusion study: in a crossover design, 11 nondiabetic HD patients were randomly assigned to receive a 4-h HD session with either: (1) no infusion, (2) glucose infusion or (3) glucose-insulin infusion. A meal was served 2 h before HD start.

RESULTS

Meal study: serum FGF21 was 23-fold higher in HD patients than controls (P < 0·001). Postprandial FGF21 decreased on all four study days (P < 0·006), but the relative reductions from baseline were significantly greater in controls (P < 0·008). Postprandial changes in FGF21 were inversely related with triglycerides (P = 0·042) and positively related with insulin-like growth factor binding protein-1 (IGFBP-1) (P < 0·001). Serum FGF21 was only associated with changes in adiponectin (P = 0·001) and free fatty acids (P = 0·04) in the healthy controls. Insulin infusion study: as compared with no infusion, glucose and glucose-insulin infusion prevented the postprandial decrease in FGF21 and resulted in higher FGF21 concentrations by up to 25% (P = 0·003).

CONCLUSIONS

Serum FGF21 was highly elevated in HD patients but the response of serum FGF21 to meal intake and insulin infusion seemed to be intact. Our results indicate that FGF21 may play an important role in short-term metabolic homoeostasis.