By Lila Rouland | Published September 12, 2025 | 3 min read
#BrownAdiposeTissue
#NewbornHealth #Endocrinology #Pediatrics #Metabolism #MetabolicAdaptation
#ClinicalResearch #Infants #BMP8B #NeonatalPhysiology
Neonatal
hypothermia remains a major health issue, particularly during the transition
from the intrauterine to the external environment. While the role of brown
adipose tissue (BAT) in heat production has long been recognized in newborns,
its underlying physiological mechanisms remained poorly understood. This
innovative study uses non-invasive infrared thermal imaging (IRT) to analyze
BAT activity in infants while also examining key hormonal markers, including
bone morphogenetic protein 8B (BMP8B), in early thermal regulation.
No needles,
no radiation: a high-tech approach for newborns
The study
involved 50 healthy full-term newborns exposed to moderate thermal stimulation:
immersion of the right foot in 19 °C water for 3 minutes on postnatal days 1
and 2. Peripheral body temperatures (arm, neck, ear) and BAT temperature
(interscapular region) were measured using IRT cameras. Blood samples were used
to assess glucose, triglycerides (TG), thyroid hormones (T3, T4), FGF21, and
BMP8B levels.
Can cold
exposure teach babies’ bodies to warm themselves?
IRT
analyses showed BAT temperature ranging from 34 to 38 °C, with a significant
linear correlation between BAT and overall body temperature, regardless of
measurement site (ear, neck, deltoid). This confirms the crucial role of BAT in
maintaining body temperature in newborns.
After cold
exposure, peripheral temperatures (especially the ear and deltoid) dropped
significantly, while BAT temperature remained stable, indicating effective
thermogenic activation. The neck region, anatomically close to BAT, better
maintained its temperature, suggesting direct local thermal influence.
Circulating
levels of BMP8B and FGF21 rose significantly after cold exposure. Among these
two hormones, only BMP8B showed a direct correlation with body and BAT
temperatures, particularly after repeated cold exposure (day 2). In contrast,
thyroid hormones (T3, T4) and glucose showed little to no association at first
but exhibited stronger links after the second exposure, indicating delayed
endocrine adaptation.
Newborns
exposed to cold from day 1 better maintained their body temperature during the
second exposure (day 2), unlike the control group. This adaptive response was
strongly correlated with BMP8B levels, not with traditional hormones,
suggesting a fundamental role of BMP8B in the rapid establishment of BAT
thermogenic capacity.
Could brown
fat become a therapeutic tool?
This study
provides new insight into the mechanisms of non-shivering thermogenesis in
infants, identifying BMP8B as a central hormonal player and a potential
biomarker of BAT activity. The use of IRT as a non-invasive monitoring tool
offers promising perspectives for safe neonatal thermal surveillance without
radiation exposure.
By
demonstrating that BAT is activated from birth and directly contributes to
thermal regulation, the study highlights the essential role of BMP8B in
establishing thermoregulation. Cold exposure acts as both a hormonal and
functional trigger for BAT, reinforcing thermal adaptation. These findings open
new clinical avenues for preventing neonatal hypothermia and its potentially
severe consequences.
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About the author – Lila Rouland
Doctor of Oncology, specialized in Biotechnology and Management
