Ng P C, Lam C W, Lee C H, Wong G W, Fok T F, Chan I H, Ma K C, Wong E
Department of Paediatrics, Level 6, Clinical Sciences Building, Prince of Wales Hospital, Chinese University of Hong Kong, Shatin, NT, Hong Kong.
Arch Dis Child Fetal Neonatal Ed. 2000 Nov;83(3):F198-202. doi: 10.1136/fn.83.3.f198.
To investigate the inter-relation between leptin and other metabolic hormones in preterm and term infants and to explore whether a functional "adipoinsular axis" might exist in preterm newborns.
A total of 140 preterm and term newborns were prospectively recruited and categorised according to gestation length. Blood samples were taken at 24 hours (day 1), and on day 4-5 of life.
Serum leptin, cortisol, free thyroxine, and plasma ACTH on day 1 were significantly higher in term than in preterm infants. The relation between serum leptin and gestation followed a non-linear pattern; the slope of the curve began to increase steeply between 33 and 35 weeks gestation. Serum leptin on day 1 was significantly associated with serum insulin, insulin:glucose ratio, and plasma ACTH in infants less than 34 weeks gestation; serum leptin on day 1 and day 4-5 were significantly correlated with insulin:glucose ratio in infants 34 or more weeks gestation. Significant changes in the pattern of metabolic hormones were observed in the first week of life. Serum insulin and plasma glucose were significantly increased between day 1 and day 4-5; serum leptin was significantly decreased.
The circulating leptin concentration increases markedly after 34 weeks gestation and bears a close temporal relation with the exponential accumulation of body fat mass during that period. The inter-relation between serum leptin and insulin or insulin:glucose ratio before and after 34 weeks gestation indicates that the "adipoinsular axis" is likely to be functional in early (<34 weeks gestation) intrauterine life. The rapid decline in the circulating concentrations of leptin after birth may be of physiological advantage to preterm and term newborns by limiting their body energy expenditure and conserving nutritional reverses for subsequent growth and development.
研究早产和足月婴儿中瘦素与其他代谢激素之间的相互关系，并探讨早产新生儿是否可能存在功能性“脂肪-胰岛轴”。
前瞻性招募了140名早产和足月新生儿，并根据孕周进行分类。在出生后24小时（第1天）以及出生后第4 - 5天采集血样。
足月婴儿第1天的血清瘦素、皮质醇、游离甲状腺素和血浆促肾上腺皮质激素水平显著高于早产婴儿。血清瘦素与孕周之间的关系呈非线性模式；曲线斜率在孕周33至35周之间开始急剧增加。孕周小于34周的婴儿中，第1天的血清瘦素与血清胰岛素、胰岛素：葡萄糖比值和血浆促肾上腺皮质激素显著相关；孕周34周及以上的婴儿中，第1天和第4 - 5天的血清瘦素与胰岛素：葡萄糖比值显著相关。在出生后第一周观察到代谢激素模式的显著变化。第1天至第4 - 5天期间，血清胰岛素和血糖显著升高；血清瘦素显著降低。
孕周34周后循环瘦素浓度显著增加，且与该时期身体脂肪量的指数性积累密切相关。孕周34周前后血清瘦素与胰岛素或胰岛素：葡萄糖比值之间的相互关系表明，“脂肪-胰岛轴”在宫内早期（孕周<34周）可能发挥作用。出生后循环瘦素浓度的快速下降可能对早产和足月新生儿具有生理优势，即限制其身体能量消耗并为后续生长发育保存营养储备。
