Serum Levels of the Adipokine Fasting-induced Adipose Factor/Angiopoietin-like Protein 4 Depend on Renal Function

Abstract

Fasting-induced adipose factor/angiopoietin-like protein 4 (FIAF/Angptl4) was recently introduced as a novel adipokine influencing glucose and lipid homeostasis. In the current study, we quantified circulating FIAF/Angtl4 levels in patients on chronic hemodialysis (CD) as compared to controls with a glomerular filtration rate above 50 ml/min. FIAF/Angptl4 was determined by ELISA in control (n=60) and CD (n=60) patients and correlated to clinical and biochemical measures of renal function, glucose and lipid metabolism, as well as inflammation, in both groups. Median serum FIAF/Angptl4 levels were more than 5-fold higher in CD patients (48.3 μg/l) as compared to control subjects (8.4 μg/l) (p<0.001). Furthermore, serum creatinine independently predicted FIAF/Angptl4 concentrations in multiple regression analyses in control subjects (p<0.01). In CD patients, C-reactive protein was independently and positively associated with circulating FIAF/Angptl4 (p<0.01). Taken together, we show that serum FIAF/Angptl4 levels are significantly increased in end-stage renal disease and independently associated with markers of renal function in control subjects.

Apolipoproteins C-I and C-III Inhibit Lipoprotein Lipase Activity by Displacement of the Enzyme from Lipid Droplets

“…Further studies are needed to corroborate this observation in vivo. Interestingly, patients with renal insufficiency have high plasma levels of both apoC-III and angptl4 (69,70). These patients are known to have low levels of LPL activity in post-heparin plasma, elevated levels of plasma triglycerides, and increased risk for cardiovascular complications (71,72).…”

Molecular mechanisms of disorders of lipid metabolism in chronic kidney disease

“…In fact, serum total and LDL cholesterol correlate positively with the serum free fatty acid levels (44). It is also important to note that ANGPTL4 inhibits hepatic lipase, thereby, limiting removal of HDL and IDL triglyceride content by the liver which can further increase plasma concentration of triglycerides (45).…”

High Concentrations of Angiopoietin-Like Protein 4 Detected in Serum from Patients with Rheumatoid Arthritis Can Be Explained by Non-Specific Antibody Reactivity

“…This can probably explain the 9-fold higher levels of ANGPTL4 reported in blood from patients with RA compared to controls, and also the large inter-individual variation of the ANGPTL4 levels (from 24 to 2235 ng/ml) reported in the same study [15]. In some other studies the concentrations of ANGPTL4 were 10 to 20 fold higher in scattered samples compared to the mean concentration obtained for the patients or controls [13, 14, 16]. In most of these studies a commercial ELISA kit for ANGPTL4 (DuoSet ELISA Development kit (DY3485) from R&D Systems) or individual antibodies from R&D Systems were used.…”