Association between serum adipocytokine and cholesterol levels in cord blood

Background: Serum leptin and adiponectin levels are strongly associated with lipid metabolism in adults. These adipocytokines play a role in intrauterine and postnatal growth but the association between cord blood levels of these adipocytokines and cholesterol at birth remains unclear. Methods: The study involved 52 appropriate‐for‐gestational‐age (AGA) infants (25 male, 27 female, 37–41 weeks of gestational age) born at Keiai Hospital without any maternal complications. Cord blood concentrations of leptin, total adiponectin, total cholesterol (TC), low‐density lipoprotein cholesterol (LDL‐C), other neonatal characteristics, and maternal factors were assessed to investigate the association between cord blood leptin or adiponectin levels and cholesterol levels. Results: Cord blood leptin levels were significantly higher in girls. Simple regression analysis indicated that cord blood leptin levels were significantly associated with birthweight, gestational age, birthweight SD score, body mass index (BMI), ponderal index, LDL‐C, and TC; but total adiponectin levels were not significantly associated with any neonatal characteristics or maternal factors. A multiple regression analysis indicated that cord leptin levels were significantly associated with BMI (β= 0.407, P= 0.001), LDL‐C (β=?0.345, P= 0.004), and infant's gender (β=?0.332, P= 0.006); adiponectin levels were significantly associated with only gestational age (β= 0.279, P= 0.047). Conclusion: Cord leptin level is significantly associated with cord cholesterol level at birth, anthropometry, and infant gender. The present study suggests that cord blood leptin may be a key hormone for controlling fetal lipid metabolism.     

脐血脂联素、瘦素水平与胎儿发育的相关性

目的 探讨脐血脂联素、瘦素水平与胎儿生长发育的关系.方法 选择2006年10月至2007年10月在我院产科出生的新生儿86例,根据不同出生体质量分为小于胎龄儿(SGA)组16例,适于胎龄儿(AGA)组41例,大于胎龄儿(LGA)组29例.胎儿娩出后立即断脐留脐血20ml,采用放射免疫分析法测定血清脂联素、瘦素水平,同时检测其血脂水平,测量新生儿生长参数,计算体质量指数(BMI).结果 (1)3组脐血瘦素和脂联素水平差异有统计学意义(P<0.001),LGA组明显高于AGA及SAG组(P<0.01);(2)脐血瘦素水平与体质量、胎龄、头围、身长、足长及胎盘重量呈正相关(P<0.01),脐血脂联素水平与出生体质量、头围、足长、BMI水平呈正相关(P<0.05).(3)脐血瘦素与脂联素水平呈显著正相关(P<0.01).(4)3组血脂水平比较差异无统计学意义;脐血脂联素、瘦素水平与血脂各指标间无明显相关性(P>0.05).结论 瘦素与脂联素在胎儿宫内生长和发育过程中起重要的调节作用.     

脐血脂联素、瘦素水平与胎儿发育的相关性

目的 探讨脐血脂联素、瘦素水平与胎儿生长发育的关系.方法 选择2006年10月至2007年10月在我院产科出生的新生儿86例,根据不同出生体质量分为小于胎龄儿(SGA)组16例,适于胎龄儿(AGA)组41例,大于胎龄儿(LGA)组29例.胎儿娩出后立即断脐留脐血20ml,采用放射免疫分析法测定血清脂联素、瘦素水平,同时检测其血脂水平,测量新生儿生长参数,计算体质量指数(BMI).结果 (1)3组脐血瘦素和脂联素水平差异有统计学意义(P<0.001),LGA组明显高于AGA及SAG组(P<0.01);(2)脐血瘦素水平与体质量、胎龄、头围、身长、足长及胎盘重量呈正相关(P<0.01),脐血脂联素水平与出生体质量、头围、足长、BMI水平呈正相关(P<0.05).(3)脐血瘦素与脂联素水平呈显著正相关(P<0.01).(4)3组血脂水平比较差异无统计学意义;脐血脂联素、瘦素水平与血脂各指标间无明显相关性(P>0.05).结论 瘦素与脂联素在胎儿宫内生长和发育过程中起重要的调节作用.     

脐血脂联素、瘦素水平与胎儿发育的相关性

目的 探讨脐血脂联素、瘦素水平与胎儿生长发育的关系.方法 选择2006年10月至2007年10月在我院产科出生的新生儿86例,根据不同出生体质量分为小于胎龄儿(SGA)组16例,适于胎龄儿(AGA)组41例,大于胎龄儿(LGA)组29例.胎儿娩出后立即断脐留脐血20ml,采用放射免疫分析法测定血清脂联素、瘦素水平,同时检测其血脂水平,测量新生儿生长参数,计算体质量指数(BMI).结果 (1)3组脐血瘦素和脂联素水平差异有统计学意义(P<0.001),LGA组明显高于AGA及SAG组(P<0.01);(2)脐血瘦素水平与体质量、胎龄、头围、身长、足长及胎盘重量呈正相关(P<0.01),脐血脂联素水平与出生体质量、头围、足长、BMI水平呈正相关(P<0.05).(3)脐血瘦素与脂联素水平呈显著正相关(P<0.01).(4)3组血脂水平比较差异无统计学意义;脐血脂联素、瘦素水平与血脂各指标间无明显相关性(P>0.05).结论 瘦素与脂联素在胎儿宫内生长和发育过程中起重要的调节作用.     

孕期增重对婴幼儿体重和肥胖风险影响的随访研究

目的：研究孕期增重对子代0~24个月内体重和肥胖风险的影响。方法：对317名孕产妇进行孕前体重、分娩前体重和一般人口统计学信息调查,在子代出生时及3、6、9、12、18、24个月龄时进行体重、身高测量和母乳喂养调查。结果：Logistic回归分析显示,孕期增重过多会显著增加子代6月龄(RR=3.56, 95% CI: 1.31~8.35)和9月龄(RR=2.87, 95% CI:1.04~3.28)时肥胖的风险,但并未增加12月龄以后的肥胖风险。线性回归模型结果显示,孕期增重与子代在出生时(β=0.032, 95% CI:0.008~0.057)、3月龄(β=0.037, 95% CI: 0.013~0.062)、6月龄(β=0.043, 95% CI: 0.017~0.068)、9月龄(β=0.038, 95% CI: 0.013~0.063)和12月龄(β=0.034, 95% CI: 0.009~0.059)时体重的Z分值间存在显著的线性关联,但这种关联在子代12个月龄后均无统计学意义。结论：孕期增重过多对子代体重发育的影响可从胎儿期持续至整个婴儿期,这种影响在生后第2年会暂时消失。     

Intracellular magnesium and adipokines in umbilical cord plasma and infant birth size

Many epidemiologic studies have disclosed that restricted fetal growth has been associated with an increased risk of insulin resistance in adulthood. We studied the relationship of intracellular magnesium [Mg2+]i in cord blood platelets to adipocytokine and birth size. The subjects were 20 infants with small for gestational age (SGA) and 45 infants with appropriate for gestational age (AGA). By using a fluorescent probe, we examined [Mg2+]i of platelets in the cord blood. Cord plasma insulin, IGF-I, ghrelin, adiponectin, plasminogen activator inhibitor-1 (PAI-1), and leptin levels were determined with the use of ELISA. Mean [Mg2+]i was lower in the SGA than in the AGA groups (p < 0.001). Adiponectin and IGF-I were also lower in the SGA than in the AGA, whereas PAI-1 was higher in the SGA. [Mg2+]i was significantly correlated with birth weight, birth length, and adiponectin. Birth weight was also correlated with cord plasma IGF-I, adiponectin, and leptin. Quantitative insulin sensitivity check index (QUICKI) was lower in the SGA group than in the AGA group. [Mg]i and adiponectin were correlated with QUICKI in all subjects. [Mg]i, as well as leptin and IGF-I, reflect the extent of fetal growth. Decreased [Mg2+]i may be involved in the underlying processes to insulin resistance.     

Long‐term effects of rapid weight gain in children,adolescents and young adults with appropriate birth weight for gestational age: the kiel obesity prevention study

Aim: This study investigates the effect of rapid weight gain in term children, adolescents and young adults born appropriate for gestational age. Methods: In all, 173 girls and 178 boys aged 6.1–19.9 (12.5 ± 3.1)years participated. Rapid weight gain (group 1) was defined as a change in weight‐SDS (standard deviation score) from birth till two years >0.67, ‘no change’ as ≥?0.67 and ≤0.67 (group 2) vs ‘slow weight gain’ as 90th age‐/sex‐specific BMI‐percentile was defined as overweight. Parental BMI, socio‐economic status and lifestyle were assessed as confounders. Results: A total of 22.8% gained weight rapidly, and 15.7% was overweight. Group 1 compared with group 2 and 3 subjects was taller, heavier and had a higher prevalence of overweight (girls/boys: 26.2%/28.9% vs 11.6%/19.0% vs 2.8%/5.0%; p < 0.01/p < 0.05). Concomitantly, a higher WC, %FM and FFM were observed. Rapid weight gain was positively associated with REE (adjusted for FFM) in boys (r = 0.26; p < 0.01), but not with cardio‐metabolic risk factors. Conclusion: Rapid weight gain was related to increases in height, weight, a higher prevalence of overweight and central fat distribution. In addition, rapid weight gain was related to a higher REE in boys, but not to cardio‐metabolic risk factors.     

Maternal and fetal serum insulin-like growth factor-I (IGF-I) IGF binding protein-3 (IGFBP-3), leptin levels and early postnatal growth in infants born asymmetrically small for gestational age

This study was planned to investigate the relationship between birth weight and insulin-like growth factor-I (IGF-I), IGF binding protein-3 (IGFBP-3), and leptin levels in neonates with normal growth (appropriate for gestational age: AGA) and retarded growth (small for gestational age: SGA); and to evaluate these growth factors' effects in early postnatal growth. All newborns were full-term: gestational age 3,841 weeks. Of 50 neonates, 25 were SGA. IGF-I, IGFBP-3 and leptin levels were measured in maternal serum and venous cord blood at birth and at 15 days of life of neonates using specific RIAs. Maternal serum leptin concentrations were significantly higher than cord blood leptin concentrations (p < 0.001). Maternal serum IGF-I, IGFBP-3 and leptin levels did not show correlations with birth weight. In contrast, there were significantly positive correlations between birth weight and venous cord blood IGF-I, IGFBP-3 and leptin levels (p < 0.001). In the SGA group, the newborns with a slow postnatal growth pattern had lower umbilical cord serum IGF-I levels compared with newborns with a normal growth pattern. A similar result was also found in the AGA group. Similar results were not found for serum leptin and IGFBP-3. In conclusion, cord blood IGF-I, IGFBP-3 and leptin levels play an important role in the regulation of fetal and neonatal growth. It is likely that IGF-I has a more important role than the other factors in early postnatal growth.     

Association of birth outcomes and postnatal growth with adult leukocyte telomere length: Data from New Delhi Birth Cohort

Born small for gestational age due to undernutrition in utero and subsequent catch‐up growth is associated with risk of developing chronic diseases in adulthood. Telomere length has been shown to be a predictor of these age‐related diseases and may be a link between birth size, a surrogate for foetal undernutrition, and adult chronic diseases. We assessed the relationship of leukocyte telomere length in adult life with birth outcomes and serial change in body mass index (BMI) from birth to adulthood. Leukocyte relative telomere length (RTL) was measured by MMqPCR in 1,309 subjects from New Delhi Birth Cohort who participated in two phases of the study between 2006–2009 (Phase 6) and 2012–2015 (Phase 7) at a mean age of 39.08 (±3.29), and its association with birth outcomes and conditional BMI gain at 2, 11, and 29 years was assessed in a mixed regression model. We did not find any significant association of RTL with body size at birth including birthweight, birth length, and birth BMI. Gestational age was positively associated with RTL (P = .017, multivariate model: P = .039). Conditional BMI gain at 2 and 11 years was not associated with RTL. BMI gain at 29 year was negatively associated with RTL in multivariate model (P = .015). Born small for gestational age was not associated with RTL in adulthood. Leukocyte telomere attrition was observed in those born before 37 weeks of gestational age as well as in those who gained weight as adults, which may predispose to chronic diseases.     

大于胎龄儿脐血脂联素水平测定及其临床意义

目的探讨大于胎龄儿(LGA)血脂联素水平变化及其对新生儿的影响。方法研究对象为LGA和适于胎龄儿(AGA)各30例。应用酶联免疫吸附法(ELISA)测定脐血和产妇血脂联素水平,用免疫比浊法测定三酰甘油(TG)、总胆固醇(TCH)、低密度脂蛋白胆固醇(LDL-c)、高密度脂蛋白胆固醇(HDL-c)水平,并分析脐血脂联素水平与母血脂联素、新生儿性别、出生体质量、体质量指数(BMI)、胎盘重量和血脂水平的相关性。结果1.LGA脐血浆脂联素水平低于AGA,差异有非常显著性(P<0.01);LGA血TG、TCH、LDL-c、HDL-c水平与AGA比较差异均无显著性(Pa>0.05)。2.LGA血浆脂联素水平与新生儿出生体质量、BMI、胎盘重量、脐血TG水平均呈显著负相关(r=-0.848,-0.785,-0.835 Pa<0.001),与母血脂联素水平、新生儿身长、孕前和分娩时产妇体质量及其BMI、其他脐血脂成分无相关性(Pa>0.05)。3.LGA男婴和女婴脐血浆脂联素、血脂各成分水平比较差异均无显著性(Pa>0.05)。结论血脂联素水平变化与LGA的发生有关,测定脐血脂联素水平有助于判断LGA的发展趋势。     

瘦素和脂联素在儿童肥胖相关性高血压发病中的作用

目的探讨瘦素和脂联素在儿童肥胖相关性高血压发病中的作用。方法基于北京市儿童青少年代谢综合征研究项目的现况调查结果，非随机选择3 502名6~18岁学龄儿童（其中男1 784名，女1 718名）为研究对象，按照超重（包括肥胖）和高血压状态将研究对象分为4组，正常体重正常血压组（对照组，1 497名）、正常体重高血压组（HBP组，125名）、超重但血压正常组（OB组，1 349名）和超重合并高血压组（OB+HBP组，531名）。通过比较4组人群血清瘦素和脂联素水平，以及瘦素和脂联素与血压之间的相关回归分析，探讨其与肥胖和血压之间的关系。结果超重肥胖人群BMI、血压、胰岛素和瘦素水平显著升高，脂联素水平降低。HBP组与对照组BMI、瘦素、脂联素水平差异无统计学意义。OB组和OB+HBP组与对照组比较，BMI、SBP、DBP、胰岛素和瘦素水平升高，脂联素水平降低，与HBP组比较仍可见BMI、胰岛素和瘦素水平升高，脂联素水平降低。与OB组比较，OB+HBP组BMI和胰岛素水平及男性的瘦素水平明显升高。血压与年龄、BMI、胰岛素、瘦素均呈显著正相关（r=0.260~0.643,P<0.01），与脂联素呈显著负相关（r=-0.171~-0.332, P<0.01）。但在调整胰岛素或BMI后，瘦素、脂联素与血压的相关性减弱或消失。结论 超重人群血压、胰岛素及瘦素水平均高于对照人群，脂联素水平低于对照人群。瘦素、脂联素可能通过肥胖或胰岛素抵抗与血压相关。     

脂联素水平在早产儿宫外生长的变化及意义

目的探讨血清脂联素水平在早产儿宫外生长中的变化及意义。方法测定74例早产适于胎龄儿出生24h内和治愈期血清脂联素与胰岛素样生长因子Ⅰ水平。同时监测早产儿体重、记录其营养摄入和并发症；分析血清脂联素水平变化及与早产儿体重的关系，分析影响早产儿宫外生长的临床因素；进行血清脂联素与胰岛素样生长因子Ⅰ水平相关性分析。结果治愈期血清脂联素水平较出生24h内明显上升（P〈0．001）；出生体质量、治愈期体质量分别对24h内和治愈期血清脂联素水平的影响有统计学意义（P〈0．01）。治愈期出现生长迟缓（治愈期体质量小于纠正胎龄平均体质量2个标准差）的早产儿出生胎龄和出生体质量以及出生24h内和治愈期血清脂联素水平均较非生长迟缓早产儿低（P〈0．05）。影响早产儿体质量标准差评分增长的因素有营养摄入、感染性疾病、机械通气〉7d、窒息缺氧（P〈0．05）。出生24h内和治愈期血清脂联素水平与胰岛素样生长因子Ⅰ水平正相关（P〈0．05）。结论早产儿体质量对血清脂联素水平有正性影响，生长迟缓早产儿血清脂联素水平低下。有效的营养和防治并发症，对防止早产儿宫外生长迟缓的发生有重要意义。     

Site -2548 of the leptin gene is associated with gender-specific trends in newborn size and cord leptin levels.

OBJECTIVE: Circulating leptin levels positively correlate with adult BMI and size at birth. Previous studies found gender-specific associations between polymorphisms in the leptin gene and postnatal obesity-related traits or circulating leptin levels. We examined the relationships among leptin gene polymorphisms, size for gestational age, umbilical cord leptin, and gender. METHODS: Six single nucleotide polymorphisms (SNPs) were genotyped in the leptin gene in 261 newborns (72 low birth weight Caucasians, 189 randomly-selected African-Americans). In African-Americans, umbilical cord leptin and free testosterone levels were measured. Linear regression was used to identify significant predictors of size for gestational age or cord leptin levels and gender x genotype interaction effects. RESULTS: There is a significant interaction between gender and genotype at site -2548 (A/G). Among low birth weight Caucasians, the A allele was associated with an increase in female size for gestational age, while the A allele was associated with decreased male birth size. Among African-Americans, the A allele was associated with a decrease in umbilical cord leptin in females and with an increase in cord leptin in males. Cord testosterone levels were not a significant predictor of cord leptin levels either among all African-American newborns or among strata of -2548 genotypes and gender. CONCLUSION: In male and female fetuses, site -2548 of the leptin gene may differently affect the expression level of the leptin gene or the rate of fetal growth. This gender-specific effect does not appear to be mediated by the level of free testosterone at delivery.     

Changes in circulating levels of adiponectin and leptin in children during the first two years of life

AIM: Adiponectin, leptin and insulin play an important role in the control of growth and glyco-metabolic homeostasis both during pre- and post-natal life. In order to find out markers indicative of post-natal growth, we evaluated circulating levels of these growth factors in full term small for gestational age (SGA) children, during the first 2 years of life, correlating them with the auxological parameters. METHODS: Fourteen SGA (8 males and 6 females) and 16 AGA (appropriate for gestional age) infants (7 males and 9 females) have been included in this study, recording length, weight, body mass index (BMI), adiponectin, leptin and insulin levels at birth. In SGA subjects, these biochemical and clinical parameters have also been evaluated at the first and at the second year of age. RESULTS: AGA and SGA adiponectin and insulin levels at birth did not show statistically significant differences, while leptin concentrations were significantly (P=0.011) lower in SGA children (median 418.49, range 157.68-903.67 pg/mL) in comparison with AGA ones (median 811.71, range 312.50-3085.95 pg/mL). CONCLUSIONS: In conclusion, at birth adiponectin and insulin levels do not differ between AGA and SGA subjects while leptin concentrations are significantly lower in SGA infants and positively correlated to the birthweight.     

Fetal and neonatal cortical adrenal function in birth asphyxia

Eighteen newborn infants, gestational age between 36 and 42 weeks with birth asphyxia were compared with 23 normal newborn infants to determine serum cortisol and dehydroepiandrosterone sulfate levels in cord blood and in venous blood samples collected 12-18 hours after birth. Both groups were similar in gestational age, birthweight, proportion of small for gestational age and large for gestational age infants, proportion of infants delivered by cesarean section with and without labor, and proportion of mothers with pre-eclampsia. There was no antenatal exposure to corticosteroid. The asphyxiated newborn infants had a significantly higher mean cord serum level of cortisol, and a significantly lower mean cord serum level of dehydroepiandrosterone sulfate than the control group. Mean serum cortisol and dehydroepiandrosterone sulfate levels collected 12-18 hours after birth were similar between both groups. It is suggested that elevated cord serum level of cortisol is related to birth asphyxia stress stimulating the adrenal definitive zone, and the low cord serum level of dehydroepiandrosterone sulfate is secondary to a transient hypoxemic-ischemic insult to the adrenal fetal zone.     

El bajo peso al nacer es un factor de riesgo de diabetes mellitus tipo 1

Introduction and aimOver recent years, the increasing incidence of type 1 diabetes mellitus (T1DM) has been associated with different factors, particularly increased obesity in childhood. The aim of this study was to find out if there was any relationship between birth weight, body mass index (BMI) increase during the first two 3 years of life, and BMI at diabetes onset with age at diagnosis, in a cohort of children diagnosed with T1DM.Material and methodData from 100 Caucasian children with T1DM of both sexes (57 boys, 43 girls) between 10 months and 16 years of age, mean age 84.45 months (SD; 52.4), were studied. We analysed the following variables: age at diagnosis, gestational age, weight and height at birth, at two years of age and at diabetes diagnosis, expressed as SD scores (SDS).ResultsAll children were between 38–40 weeks of gestational age. Diabetic patients have lower birth weight (?2.88 ((?0.51)–(?0.066)) and lower BMI at birth compared with healthy children ?0.5 ((?0.77)–(?0.23)). Diabetic children have a significant increase in BMI during the first two years of life (4.58 versus 2.17; P<0.001). Children with the lowest BMI at birth (12.77 versus 13.06; P<0.006) are the youngest at onset of the disease. BMI at diagnosis was not related to any of the variables studied. There were no gender differences either.ConclusionsThe low BMI at birth and the later increase in the following years of life seem to be related to intrauterine environment as a risk factor for T1DM.     

Ghrelin and adiponectin levels in colostrum,cord blood and maternal serum

Background: Ghrelin and adiponectin, which are considered to take part in the regulation of energy metabolism, have been found in breast milk and cord blood. The aims of this study were to determine ghrelin and adiponectin levels in colostrum, cord blood and maternal serum and to investigate the correlations between colostrum and cord blood levels of these peptides and the anthropometry of newborn infants and their mothers. Methods: Total ghrelin (TGHR), free ghrelin (FGHR) and adiponectin levels were studied in colostrum and the serum samples of 25 healthy lactating women and the cord blood of their healthy full‐term infants. Results: No significant differences could be found among TGHR and adiponectin levels in colostrum, cord blood and maternal serum. The median FGHR level in colostrum was significantly higher than that of maternal serum and cord blood. The colostrum TGHR was negatively correlated with body mass index (BMI) and weight of the infants at birth. TGHR and FGHR levels in colostrum were found to be positively correlated with those of maternal TGHR and FGHR concentrations, respectively. Adiponectin levels in colostrum were not correlated with BMI or birthweight of the infants or BMI of the mothers. Conclusion: These findings suggest that the source of ghrelin in breast milk is probably both breast tissue itself and the serum of the mother. Ghrelin in colostrum seems to be related to the anthropometry of infants even at birth, unlike adiponectin.     

Longitudinal investigation of the relationship between breast milk leptin levels and growth in breast-fed infants

BACKGROUND: It has been shown that leptin is present in breast milk and human mammary epithelial cells are able to synthesize leptin. It has been suggested that leptin in human milk might be involved in the regulation of postnatal nutrition and growth. AIMS: To investigate whether there is a relationship between leptin levels in human milk and weight gain in the postnatal period and to compare variations of milk-borne maternal leptin concentrations for small for gestational age (SGA), large for gestational age (LGA) and appropriate for gestational age (AGA) infants. INFANTS AND METHODS: Forty-seven healthy lactating women aged from 17-38 years and their infants were included in the study. The infants were separated into three groups according to birth weight as SGA (n = 11), LGA (n = 14) and AGA (n = 22). All infants were fed with breast milk during the study period. Anthropometric measurements were performed on the 15th day of life and at 1, 2, and 3 months of age, and the body mass index (BMI) of the infants' mothers was calculated. Breast milk leptin levels were analyzed by radioimmunoassay. RESULTS: Breast milk leptin levels were found reduced in the SGA group and increased in the LGA group compared to the AGA group at 15 days of life (13.4 +/- 2.2, 28.5 +/- 4.4 and 18.4 +/- 2 ng/ml, respectively; p <0.05). At 1 month of age, leptin levels in breast milk were significantly lower in the LGA group than in the AGA group (15.5 +/- 4.9, 19.4 +/- 1.7 ng/ml, respectively; p<0.05). There was no difference among the three groups at 2 and 3 months of age (p>0.05). There was a positive correlation between birth Weight and breast milk leptin levels on the 15th day (r = 0.47, p = 0.001). A negative correlation was found between weight gain during the first 15 days and 1 month of life and breast milk leptin levels on the 15th day (r = -0.44, p = 0.002; r = -0.40, p = 0.005, respectively). No relationship could be determined between breast milk leptin levels and BMI of the mothers. CONCLUSION: Maternal milk of SGA, LGA and AGA infants had different leptin levels, especially during the first month of life. More rapid growth was shown in the SGA infants during the first postnatal 15 days compared to AGA and LGA infants, and human milk leptin levels were significantly reduced in the SGA group. However, LGA infants gained more weight during the second 15 days of life and breast milk leptin levels were dramatically decreased in LGA and increased in SGA infants at the end of first month of life. These findings suggest that the presence of leptin in breast milk might have a significant role in growth, appetite and regulation of nutrition in infancy, especially during the early lactation period, and the production of leptin in breast tissue by human mammary epithelial cells might be regulated physiologically according to necessity and state of the infant.     

Cord blood and postnatal serum leptin and its relationship to steroid use and growth in sick preterm infants

OBJECTIVE: To study the effect of prenatal and postnatal glucocorticoids use on serum leptin and weight gain in sick preterm infants and its correlation with caloric intake. METHODS: Serum leptin was measured in 24 neonates at day 1 (cord), 14 and 28 by radioimmunoassay. Total caloric intake (enteral and parenteral) and weight were measured on days 14 and 28 of life. RESULTS: Mean birth weight and gestational age of study infants were 864 +/- 273 g (mean +/- SD) (range 520-1755 g), and 26.6 +/- 2.4 weeks (23-32 weeks) respectively. Cord blood leptin was greater in infants whose mothers received antenatal steroids (1.98 +/- 1.05 ng/ml vs 0.94 +/- 0.39 ng/ml, p=0.004). Serum leptin increased postnatally from 1.52 +/- 1.0 ng/ml at birth to 2.2 +/- 1.3 ng/ml on day 28 of life (p=0.03). Mean serum leptin had an inverse exponential relationship with postnatal weight gain by day 28 of life (R2=0.56). Total caloric intake on days 14 and 28 of life did not correlate with postnatal weight gain. CONCLUSIONS: Increased serum concentration of leptin following glucocorticoids may be associated with poor weight gain in sick preterm infants.     

Circulating levels of adiponectin in preterm infants

OBJECTIVE: To determine circulating levels of adiponectin in preterm infants and examine possible associations with anthropometric measurements, weight gain, and leptin and insulin levels. DESIGN: Prospective study. SETTING: A university hospital neonatal care unit. Study population: 62 preterm (mean (SD) gestational age 32.0 (2.1) weeks) and 15 full-term infants (reference group). INTERVENTIONS: Blood samples taken at discharge (40.9 (14.8) days of life) from the preterm infants and at a comparable postnatal age in full-term infants. All infants were fed the same commercial formula, but in nine preterms the formula contained long-chain polyunsaturated fatty acids (LCPUFAs). MAIN OUTCOME MEASURES: Serum levels of adiponectin, leptin and insulin. Associations of adiponectin levels were tested only in the preterm group. RESULTS: Serum levels of adiponectin were lower in preterm (40.9 (14.8) microg/ml) than full-term infants (53.1 (16.0) microg/ml, p<0.01). However, after adjustment for body weight, the influence of prematurity on adiponectin levels was no longer significant. In preterm infants, adiponectin levels independently correlated with being born small for gestational age (SGA) (beta=-0.35, p=0.01), weight gain (beta=0.28, p=0.03) and LCPUFA-supplemented formula (beta=0.34, p=0.009). Serum adiponectin levels did not correlate with insulin or leptin levels. However, insulin levels were higher in preterm than in full-term infants after adjustment for body weight. CONCLUSIONS: Adiponectin levels are lower in preterm infants at discharge than full-term infants probably due to decreased adiposity. The levels are influenced by being born SGA, weight gain and, possibly, by dietary LCPUFAs. The importance of these findings in the development of insulin or leptin resistance in children born prematurely needs to be further studied.