Posterior cervical brown fat and CXCL14 levels in the first year of life: sex differences and association with adiposity

Context: Brown adipose tissue (BAT) is particularly abundant in neonates but its association with measures of adiposity and metabolic health in early infancy is poorly delineated. Besides sustaining non-shivering thermogenesis, BAT secretes brown adipokines that act on systemic metabolism. The chemokine CXCL14 has been identified as a brown adipokine in experimental studies. Objective: To determine the relationships among BAT activity, adiposity and circulating CXCL14 levels in the first year of life in girls and boys. Design, setting and participants: Indices of fat accretion, circulating endocrine-metabolic parameters and serum CXCL14 levels were assessed longitudinally in a cohort of infants at birth and at 4 and 12 months. BAT activity was estimated using infrared thermography only at age 12 months. Main outcome measures: Weight and length Z-scores, total and abdominal fat content (by DXA), BAT activity at the posterior-cervical and supraclavicular regions, serum levels of ...Context: 棕色脂肪组织（brown adipose tissue, BAT）在新生儿体内含量尤为丰富，但目前其与婴儿早期体脂指标及代谢健康的关联尚未明确。除维持非颤抖产热功能外，BAT还可分泌作用于全身代谢的棕色脂肪因子。已有实验研究证实趋化因子CXCL14为一种棕色脂肪因子。 Objective: 旨在探究男女婴幼儿出生后第一年中，BAT活性、体脂水平与循环CXCL14浓度之间的关联。 Design, setting and participants: 本研究对某婴儿队列进行纵向随访，分别在出生时、4月龄及12月龄时评估其脂肪堆积指标、循环内分泌代谢参数及血清CXCL14水平；仅在受试者12月龄时，采用红外热成像技术估算其BAT活性。 Main outcome measures: 体重与身长Z评分、全身及腹部脂肪含量（双能X线吸收测定法，DXA）、颈后及锁骨上区域的BAT活性，以及血清……水平。