Increased circulating
fibroblast growth factor (FGF)-21 and sclerostin levels have been reported in patients with
type 2 diabetes (T2D). We assessed the association of
FGF-21 and sclerostin with adiposity, glycemia, and glucoregulatory measures in healthy subjects. We studied 20 normoglycemic Black and White offspring of parents with T2D. Assessments included oral
glucose tolerance test,
insulin sensitivity (Si-clamp), insulin secretion (homeostasis model assessment index of b-cell function [HOMA-B]), and body fat (dual-energy X-ray absorptiometry). Fasting plasma
FGF-21 and sclerostin levels were measured with
enzyme-linked
immunosorbent assays. The participants' mean (+SD) age was 50.4 ± 5.97 years; body mass index (BMI) 32.5 ± 5.86 kg/m2; fasting plasma
glucose (FPG) 96.1 ± 5.21 mg/dL, and 2-hour postload
glucose 116 ± 5.45 mg/dL.
FGF-21 levels were similar in Black people vs White people (0.36 ± 0.15 ng/mL vs 0.39 ± 0.25 ng/mL), men vs women (0.45 ± 0.14 vs 0.44 ± 0.07 ng/mL), correlated positively with BMI (r = 0.23, P = .05) and waist circumference (r = 0.27, P = .04), and inversely with FPG (r = -0.26, P = .05). Sclerostin levels also were similar in Black people (33.5 ± 17.1 pmol/L) vs White people (34.2 ± 6.41 pmol/L), men vs women (35.3 ± 9.01 pmol/L vs 32.3 ± 15.8 pmol/L), and correlated inversely with FPG (r = -0.11 to -0.44) but not adiposity measures. The correlation coefficient between Si-clamp values and
FGF-21 levels was -0.31 (P = .09) compared with 0.04 (P = .89) for sclerostin levels.
FGF-21 and sclerostin levels were not correlated with each other or HOMA-B. Among healthy Black and White subjects, plasma
FGF-21 and sclerostin showed differential associations with adiposity but concordant association with FPG levels.