Association of circulating FGF-21 levels in the first week of life and postnatal growth in hospitalized preterm infants

Abstract

Background The role of fetal and neonatal growth in the development of adult-onset diseases such as obesity and metabolic syndrome has become increasingly appreciated. Fibroblast growth factor-21 (FGF-21) is known as a regulator of glucose and lipid metabolism. FGF-21 levels are elevated in obese adults and children. The role of FGF-21 in neonatal growth in preterm infants is not known. Objectives We aimed to evaluate the association of circulating FGF-21 levels in the first week of life and neonatal growth parameters at the time of discharge from NICU. Methods We performed a longitudinal study of 25 preterm neonates admitted to NICU. Blood samples were collected at two time points: within 24 h of life (T1), and 24–96 h after the first blood draw (T2). FGF-21 levels were measured in plasma by ELISA. Weight, length, BMI and their Z-scores were measured at the time of birth and discharge. Results The FGF-21 levels were significantly higher at T2 than at T1 (p < 0.001). FGF-21 levels at both time points were positively correlated with gestational age (r = 0.43, p = 0.03). FGF-21 at T1 was positively associated with weight Z-score (β = 0.19, p = 0.001) and length Z-score at discharge (β = 0.21, p = 0.03). Conclusions Circulating FGF-21 levels increase significantly in the first week, and the FGF-21 levels within the first 24 h are positively associated with weight and length Z-scores at discharge in preterm infants. These results suggest that FGF-21 may be involved in growth and developmental maturation.

The interplay between birth weight and obesity in determining childhood and adolescent cardiometabolic risk

“…FGF21 has previously been shown to be elevated in individuals with obesity, MASLD, and T2D, 30 and studies in newborn infants suggest that FGF21 is involved in early growth and development. 31 HAOX1 is a liver-specific peroxisomal enzyme, and emerging evidence has linked it to chronic liver disease. 32 Leptin is a key player in fat mass regulation and appetite control, and it has been implicated in the regulation of early adiposity.…”

Cooling down with Entresto. Can sacubitril/valsartan combination enhance browning more than coldness?

“…Actually, this growth factor increases energy expenditure and core temperature likely via induced FFA catabolism and perhaps through thermogenic activation of brown adipocytes [ 91 ]. Liver-derived FGF21 is capable of activating thermogenesis in neonatal brown fat cells, and it is highly expressed in adults BAT [ 92 ]. A study examining the circulating levels of FGF21 showed that mild cold exposure increased the level of this transcriptional factor of browning which is associated with intensified BAT activation.…”

FGF21 via mitochondrial lipid oxidation promotes physiological vascularization in a mouse model of Phase I ROP

“…In full-term infants, FGF21, synthesized in the liver [ 27 ], is induced from postnatal day 2 through the first year [ 28 ]. However, in preterm infants, circulating levels of FGF21 are below the lower limit of quantitation (LLOQ) of the assay in 85% of preterm infants at birth (cord blood), and in 31%, and 25% at 1 and 3 weeks, respectively [ 29 – 31 ]. Interestingly, FGF21 levels in the first 24 h positively correlate with infant weight and length Z-scores at discharge [ 31 ].…”

“…However, in preterm infants, circulating levels of FGF21 are below the lower limit of quantitation (LLOQ) of the assay in 85% of preterm infants at birth (cord blood), and in 31%, and 25% at 1 and 3 weeks, respectively [ 29 – 31 ]. Interestingly, FGF21 levels in the first 24 h positively correlate with infant weight and length Z-scores at discharge [ 31 ]. In the offspring of pregnant women with normal glucose tolerance, cord blood FGF21 levels also positively correlate with postnatal growth of infants [ 32 ].…”