Fibroblast growth factor 21 (FGF-21) in obese children: no relationship to growth, IGF-1, and IGFBP-3
Insights
Fibroblast growth factor 21 (FGF-21) does not appear to impact growth in obese children, even after significant weight loss. Further research is needed to understand growth hormone axis alterations in this population.
Area of Science:
- Pediatric Endocrinology
- Metabolic Research
- Growth Hormone Axis
Background:
- Fibroblast growth factor 21 (FGF-21) is a key metabolic regulator in the liver, adipose tissue, and bone.
- Animal studies suggest FGF-21 increases with undernutrition and correlates with growth disturbances.
- The role of FGF-21 in pediatric obesity and growth remains unclear.
Purpose of the Study:
- To investigate the impact of weight loss in obese children on growth parameters.
- To examine the relationship between FGF-21, insulin-like factor 1 (IGF-1), and growth.
- To assess changes in FGF-21, IGF-1, and other metabolic markers following a lifestyle intervention.
Main Methods:
- A 1-year lifestyle intervention was conducted in 60 obese children (30 with substantial weight loss, 30 with stable BMI-SDS).
- Measurements included height, serum FGF-21, IGF-1, IGFBP-3, leptin, and insulin at baseline and 1 year.
- Statistical analyses included multiple linear regression adjusted for age, gender, and pubertal stage.
Main Results:
- Baseline height was associated with IGF-1 and leptin, but not FGF-21 or insulin.
- FGF-21 showed no significant association with IGF-1 or IGFBP-3 in cross-sectional analysis.
- Longitudinal analysis revealed no significant relationship between changes in FGF-21 and changes in height or IGF-1; however, FGF-21, leptin, and insulin decreased in the weight loss subgroup.
Conclusions:
- Findings do not support a role for FGF-21 in the growth of obese children, as no significant associations with growth or IGF-1 were observed.
- Further research is required to elucidate the complex alterations within the growth hormone axis in obese children.
- Weight loss in obese children is associated with reductions in FGF-21, leptin, and insulin.
Background:
Fibroblast growth factor 21 (FGF-21) is a hepatic protein that plays a critical role in liver, adipose tissue, and bone metabolism. Animal models reported an increase of FGF-21 and associated growth disturbances in undernutrition. Therefore, we studied the impact of weight loss in obese children on growth, FGF-21, and insulin-like factor 1 (IGF-1) concentrations.
Methods:
We analyzed height, serum concentrations of FGF-21, IGF-1, IGFBP-3, leptin, and insulin at baseline and 1 year later in 30 obese children with substantial weight loss (reduction >0.5 BMI-SDS) and in 30 obese children of similar age, gender, and pubertal stage with stable BMI-SDS. All children participated in a 1-year lifestyle intervention. Height and IGF-1 was transformed to standard deviation score (SDS). Multiple linear regression analyses adjusted for age, gender, and pubertal stage were performed.
Results:
At baseline, height-SDS was significantly related to IGF-1-SDS (β-coefficient 0.68 95% confidence interval (95% CI)±0.49; p=0.008) and leptin (β-coefficient 0.042 95% CI±0.030; p=0.008), but not to FGF-21 or insulin. FGF-21 was not significantly associated with IGF-1 or IGFBP-3. In longitudinal analysis, changes of FGF-21 were not significantly related to changes of height, IGF-1-SDS or IGFBP-3. However, in the subgroup of 30 children with substantial BMI-SDS reduction, FGF-21, leptin, insulin, and HOMA decreased significantly.
Conclusion:
As there was no significant association between FGF-21 and growth or IGF-1 both in cross-sectional and longitudinal analyses, these findings do not support the hypothesis that FGF-21 is involved in growth of obese children. Further studies are necessary to understand the multiple alterations in the growth hormone (GH) axis in obese children.
Related Concept Videos
01:24Obesity
01:09Introduction to Fibroblasts
01:25Ultrasound II: Endoscopic Ultrasound and FibroScan
Endoscopic Ultrasound (EUS):