Maffei M, Volpe L, Di Cianni G, Bertacca A, Ferdeghini M, Murru S, Teti G, Casadidio I, Cecchetti P, Navalesi R, Benzi L
Department of Metabolic Disease, University of Pisa, Italy.
Horm Metab Res. 1998 Sep;30(9):575-80. doi: 10.1055/s-2007-978936.
Leptin can be considered as a peripheral signal which informs the centers about the mass of energy stores. Studies done on the human adult population have demonstrated that degree of adiposity and insulin levels play a major role as determinants of leptin circulating levels. The aim of this study was to evaluate which factors may influence leptin levels at birth. We examined the role played by baby size and by the metabolic environment the fetus was exposed to during pregnancy. We considered 85 newborns from normal (n = 60), gestational (GDM, n = 17) and pregestational (IDDM = 8) diabetes mellitus mothers. At delivery, blood was taken from the umbilical cord vein. Babies from normal and GDM mothers were subdivided into AGA (appropriate for gestational age) and LGA (large for gestational age). There was no difference in leptin levels between babies from normal or GDM mothers belonging to the same weight category, but leptin levels were always higher in LGA than in AGA newborns, and highly correlated with birth weight (r = 0.34, P = 0.001). Moreover, IDDM mothers gave birth to newborns with significantly higher levels of leptin and insulin when compared with normal and GDM mothers. Diabetes of both GDM and IDDM mothers was clinically well controlled (HbA1c was 4.0 and 7.2, respectively). The correlation between leptin and insulin was significant only when newborns from IDDM mothers were included in the regression analysis (r = 0.39, P = 0.0002). Our results suggest that degree of adiposity is one of the main regulators of leptin concentration in the human newborn and that babies exposed to an altered, though clinically controlled, metabolic environment, as in IDDM mothers, have increased levels of leptin.
瘦素可被视为一种外周信号，它将能量储备量的信息传递给中枢。针对成年人群体开展的研究表明，肥胖程度和胰岛素水平作为瘦素循环水平的决定因素发挥着主要作用。本研究的目的是评估哪些因素可能会影响出生时的瘦素水平。我们研究了婴儿出生体重以及胎儿在孕期所处的代谢环境所起的作用。我们纳入了85名分别来自正常（n = 60）、妊娠期（妊娠期糖尿病，GDM，n = 17）和孕前（1型糖尿病，IDDM = 8）糖尿病母亲的新生儿。分娩时，从脐静脉采集血液。来自正常和GDM母亲的婴儿被分为适于胎龄儿（AGA）和大于胎龄儿（LGA）。属于相同体重类别的正常或GDM母亲的婴儿之间，瘦素水平没有差异，但LGA新生儿的瘦素水平总是高于AGA新生儿，且与出生体重高度相关（r = 0.34，P = 0.001）。此外，与正常和GDM母亲相比，IDDM母亲所生新生儿的瘦素和胰岛素水平显著更高。GDM和IDDM母亲的糖尿病在临床上均得到良好控制（糖化血红蛋白分别为4.0和7.2）。仅当将IDDM母亲的新生儿纳入回归分析时，瘦素与胰岛素之间的相关性才显著（r = 0.39，P = 0.0002）。我们的结果表明，肥胖程度是人类新生儿瘦素浓度的主要调节因素之一，并且如在IDDM母亲的情况中，处于虽经临床控制但已改变的代谢环境中的婴儿，其瘦素水平会升高。
