Association of Fibroblast Growth Factor (Fgf-21) as a Screening Biomarker for Chronic Progressive External Ophthalmoplesia

Purpose: To investigate whether or not fibroblast growth factor (FGF-21) can be used as a screening biomarker in chronic progressive external ophthalmoplesia (CPEO) patients.
Methods: FGF-21 concentration was measured in the serum of 24 patients with CEPO phenotype and 24 control samples by enzyme-linked immunosorbent assay (ELISA) and determined the deletion of mitochondrial genome by multiplex polymerase chain reaction (PCR).
Results: FGF-21 concentration in 50 % of CPEO patients showed notable differences from that in control subjects. FGF-21 concentration ratio in patient group, 2 disorder control groups (mitochondrial and non-mitochondrial) and normal group, respectively, was 294.87 ± 42.10 (p < 0.0001), 761.78± 75.07 (p < 0.0001), 124.26 ± 12.27 (p = 0.1203), 69.27 ± 10.09 (p = 0.2195). A statistically significant inverse correlation between FGF-21 concentration and age onset was found, with a significant difference (p < 0.05) in the age group ≤ 19 years (mean FGF-21 concentration, 460.36 pg/mL) and for the age group ≥ 51years (mean concentration FGF-21, 57.87 pg/mL. Surprisingly, there was no significant difference between FGF-21 concentration and age in the mid-age group (20 – 50 years).
Conclusion: These findings indicate that FGF-21 concentration significantly increases in CPEO patients like in other mitochondrial disorders and this factor can be used as a biomarker in primary diagnosis of mitochondrial disorders. In this regard, FGF-21 assay is only valid in teenagers and the > 50 years age group who show acute symptoms.

Keywords
Chronic progressive external ophthalmoplesia; Fibroblast growth factor-21; Mitochondrial disorders; Ophthalmoplesia; Biomarker