Relationship Between Circulating FGF21 and Bone Mineral Density: An Exploratory Study
IntroductionFibroblast growth factor 21 (FGF21) has metabolic regulating effects on the body and exhibits endocrine-like effects on the body. Prior research has indicated that FGF21 may modulate bone density; however, the extent to which FGF21 can alter bone density and the effect of biological sex remains understudied. MethodsA total of 25 individuals (Female = 13, Male =12) volunteered to have their whole body bone density measured using Dual X-Ray Absorptiometry (DEXA) and blood drawn on two separate occasions. Serum samples were analyzed for FGF21 concentration and concentration value was averaged between the two samples, all blood samples were drawn during the mid-follicular phase in female participants. The relationship between FGF21 and markers of bone density was examined using Pearson correlations. ResultsWhole-body BMD (wb-BMD) was negatively correlated with FGF21 across the whole sample (r = -0.53, p < 0.05). When stratifying the sample by biological sex, wb-BMD was negatively correlated with FGF21 in females (r = -0.72, p < 0.05) and in males (r = -0.18, p > 0.05); however, in males this relationship was not statistically significant. ConclusionFGF21 appears to be negatively correlated to bone density in humans with a significant relationship in females but not in males.