Common adipokine features of neonates and centenarians

Adipose tissue seems to be a pivotal organ in the aging process. We investigated whether healthy aging could have its roots in a sound metabolic condition from the first year of life by evaluating leptin and adiponectin levels in neonates [33 adequate for gestational age (AGA) and 29 small for gestational age (SGA)], 48 centenarians, and 50 healthy elderly subjects. At birth, SGA neonates showed lower leptin levels (SGA 0.88 +/- 0.28; AGA 2.22 +/- 0.91 ng/mL; p < 0.05) and comparable adiponectin levels with respect to AGA. At 1 year, SGA showed increased leptin (SGA 1.74 +/- 0.28; AGA 1.31 +/- 0.19 ng/mL) and slightly reduced adiponectin concentrations (SGA 35.51 +/- 2.53; AGA 38.56 +/- 3.18 microg/mL) than AGA. Centenarians showed lower leptin (centenarians 18.71 +/- 3.78; elderly 34.81 +/- 7.27 ng/mL; p < 0.05) and higher adiponectin levels (centenarians 55.63 +/- 7.7; elderly 33.51 +/- 4.1 microg/mL; p < 0.05) than elderly subjects. Centenarians, like AGA infants during the first year of life, show a favorable adipokine profile, suggesting that the metabolic condition at early age could affect the longevity of an individual.     

Cardiac hypertrophy and altered hemodynamic adaptation in growth-restricted preterm infants

The objective was to elucidate hemodynamic adaptation in very low birth weight (<1500 g) infants after intrauterine growth retardation. 31 growth-retarded (SGA, birth weight <-2 SD) and 32 appropriate for gestational age (AGA, birth weight within +/- 1 SD range) infants were enrolled. In SGA infants, the diastolic diameters of the interventricular septum and the left ventricle were increased, and serum brain natriuretic peptide (BNP) was elevated. Left ventricular output (LVO) of the AGA infants increased from 150 +/- 28 to 283 +/- 82 mL/kg/min during the study (p < 0.01). The SGA infants had a higher initial LVO than the AGA infants (243 +/- 47 versus 150 +/- 28 mL/kg/min, p < 0.05), but did not show further LVO increase during the study period. Red cell (RCV) and blood (BV) volume were assessed by Hb subtype analysis, when packed donor red cells were transfused. RCV and BV did not differ between the groups initially, but RCV increased by 18% and BV by 29% in the AGA group during the first 3 d. On day 3, AGA infants had larger BV than the SGA infants (88 +/- 5 versus 73 +/- 12 mL/kg, p < 0.05). In conclusion, cardiac hypertrophy, elevated initial LVO and BNP of the SGA infants suggest increased cardiac workload after intrauterine growth retardation. Based on the BV and RCV data, blood volume regulation may also be impaired. The data suggest that SGA preterm infants may be exposed to an increased risk of circulatory failure during early adaptation.     

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.     

Insulin, insulin-like growth factors-I and -II and insulin-like growth factor binding protein-3 in newborn serum: association with normal fetal head growth and head circumference

The insulin-like growth factors (IGF) and their binding proteins (IGFBP) have been implicated in the regulation of fetal weight and length. The aim of our study was to determine the relationship between head circumference at birth and serum levels of IGF-I, IGF-II, IGFBP-3 and insulin in full-term appropriate-for-gestational age (AGA) infants. Serum samples were obtained from 77 singleton full-term neonates, 69 AGA and 8 small-for-gestational age (SGA). The AGA infants were divided into three groups by head circumference: Group 1: < or = 3rd percentile; Group 2: at 50th percentile; Group 3: > or = 97th percentile. Serum levels of IGF-I, IGF-II, IGFBP-3 and insulin were determined with commercial kits and immunometric methods. There were no statistically significant differences in mean serum levels of IGF-I, IGF-II and IGFBP-3 between the groups. A significantly higher mean serum insulin level was noted in the AGA infants with a head circumference > or = 97th percentile compared to those with a head circumference < or = 3rd percentile (4.6 +/- 0.3 vs 3.3 +/- 0.6 microU/ml; p = 0.04), and in AGA infants with a head circumference above the 50th percentile compared to those with a head circumference below the 50th percentile (4.4 +/- 0.4 vs 3.3 +/- 0.3 microU/ml; p = 0.01). AGA infants with a head circumference above or below the 50th percentile did not differ statistically in their mean IGF-II and IGFBP-3 serum level, while IGF-I differed statistically between the groups (18 +/- 2.7 vs 11.6 +/- 1.6 ng/ml, respectively; p = 0.045). Using univariate analysis, head circumference correlated positively with insulin (r = 0.29; p = 0.016) and with IGF-I (r = 0.26; p = 0.03). A stepwise multivariate linear regression analysis, however, did show statistically significant correlation of head circumference with birth weight (f = 36; p = 0.0001), and only marginally with birth length (f = 4.7; p = 0.06) and insulin (f = 3.4; p = 0.07). No correlations were found between head circumference and IGF-I, IGF-II or IGFBP-3. These data suggest that apart from genetic and nutritional factors, insulin may play a role in promoting intrauterine head growth, as reflected by head circumference at birth.     

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.     

The influence of gestational age, size for dates, and prenatal steroids on cord transferrin levels in newborn infants

Serum transferrin levels assess protein status in older children and adults. To generate standards for its use in newborn infants, we measured umbilical cord serum transferrin levels in 161 appropriate (AGA), 25 large (LGA) and 16 small (SGA) for gestational age infants between 25 and 43 weeks' gestation. We also assessed the effects of intrauterine growth, exposure to prenatal steroids, and presence of pulmonary maturity on neonatal transferrin levels. Cord transferrin levels in AGA infants were significantly correlated with increasing gestational age (r = 0.60; p less than 0.001). Infants born before 37 weeks' gestation had significantly lower transferrin levels, when compared with those born at term (p less than 0.001). LGA infants had significantly higher levels than age-matched AGA infants (253 +/- 75 vs. 214 +/- 53 mg/dl; p less than 0.025). Despite significantly lower mean birth weights (p less than 0.001), SGA infants also had significantly higher levels than gestational age-matched AGA controls (227 +/- 63 vs. 167 +/- 40 mg/dl; p less than 0.005). For infants less than 35 weeks' gestation, neither the 20 preterm infants with exposure to prenatal steroids (maternal betamethasone), nor the 26 infants with pulmonary maturity had significantly elevated transferrin levels, when compared with gestational age-matched control infants. Newborn transferrin levels correlate well with gestational age and are significantly affected by size for dates, but not by a brief course of prenatal steroids or by pulmonary maturity.     

小于胎龄足月新生儿和适于胎龄足月新生儿血清瘦素及胰岛素水平的变化

目的 探讨不同类型足月新生儿血清瘦素及胰岛素水平及其与胎儿宫内生长发育的关系.方法 收集2009年9月-2010年5月在山西省儿童医院新生儿科住院的无严重疾病的88例足月新生儿的临床资料,其中44例小于胎龄儿(SGA),44例适于胎龄儿(AGA),用酶联免疫吸附测定法(ELISA)检测其出生24 h内血清瘦素及胰岛素水平,并分析血清瘦素和胰岛素水平与出生体质量的关系.采用SPSS 17.0软件进行统计学分析.结果 AGA组血清瘦素水平及血清胰岛素水平均高于SGA组(t=-73.624、-11.729,Pa<0.01);血清瘦素水平及血清胰岛素水平与出生体质量均呈正相关(r=0.96、0.91,Pa<0.01);血清瘦素与胰岛素之间也存在正相关(r=0.85,P<0.01).结论 瘦素及胰岛素在一定程度上反映了胎儿宫内生长发育的情况,在调节足月儿的生长代谢中发挥了重要作用.     

脑源性神经营养因子与新生儿出生体重的关系

目的：该文通过检测新生儿脐血脑源性神经营养因子（brain-derived neurotrophic factor,BDNF）的水平,探讨BDNF与新生儿出生体重的关系,并对相关因素进行分析。方法：根据出生体重,将51 例足月第1胎健康新生儿分为3 组:①小于胎龄组（SGA）8例;②适于胎龄组（AGA ）31例;③大于胎龄组（LGA）12例。测量新生儿身长、体重及其母亲的身高、体重,并对脐血中BDNF、瘦素（LEP）、胰岛素（INS）、总胆固醇（TC）、甘油三酯（TG）进行检测。结果：SGA组的BDNF明显高于AGA组和大于LGA组,AGA组和LGA组中BDNF没有差异;多元逐步回归分析显示BDNF值与新生儿出生体重、体重指数存在负相关关系。LEP与BDNF不呈相关趋势（P>0.05）,INS与BDNF也不呈相关趋势（P>0.05）。INS 与LEP呈现正相关（P<0.05）。LEP与新生儿体重、产妇体重及其BMI呈正相关,而TC,TG在3组新生儿中差异无显著性。结论：BDNF是新生儿体重的重要影响因素,而且不受LEP,INS的影响。     

Whole blood fatty acid composition differs in term versus mildly preterm infants: small versus matched appropriate for gestational age

To investigate the associations between whole blood fatty acid (FA) profile and restricted intrauterine growth, any small for gestational age (SGA) infant born in our maternity ward through 1 y was matched with two appropriate for gestational age (AGA), of the same GA +/- 0.5 wk, infants, further subdivided into term and preterm. Whole blood was collected at d 4 on a strip and FA % composition assessed by means of gas chromatography. The whole sample consisted of 28 SGA versus 56 AGA born at term and 20 SGA versus 40 AGA born preterm at around 35 wks. Parent FA of the n-6 and n-3 FA families were higher in preterm groups, whereas docosahexaenoic acid was higher in term AGA (median % values, 3.9 versus 3.7 in term SGA, 2.8 in preterm AGA, and 2.5 in preterm SGA, p < 0.001). Term AGA had markedly higher values for the docosahexaenoic acid/alpha-linolenic acid ratio (median value: 91, versus 18 in term SGA, 12 in preterm AGA, and 10 in preterm SGA, p < 0.001). Term SGA had significantly lower levels of total monounsaturated FA and higher levels of eicosapentaenoic acid. Therefore, the 4-d whole blood FA pattern is associated with both GA and birth weight.     

Intrauterine growth restriction and postnatal steroid treatment effects on insulin sensitivity in preterm neonates

OBJECTIVES: To study whether intrauterine growth restriction (IUGR) is associated with decreased sensitivity to the main fetal growth factor, insulin, and the effect of glucocorticoid therapy on insulin sensitivity in preterm infants. STUDY DESIGN: Newborn infants with a birth weight (BW) of< 1500 g were classified as appropriate for gestational age ([AGA], BW within +/- 1 SD, n = 10), or small for gestational age ([SGA], BW <-2 SD, n = 13); 5 AGA infants and 8 SGA infants received systemic steroids. An abbreviated modified minimal model test was performed, consisting of sequential blood samples for glucose and insulin assays, and intravenous infusions of 0.3 g/kg glucose and 0.02 U/kg regular human insulin. The insulin sensitivity index (S(I)) was calculated using a computer program. RESULTS: The basal insulin/glucose ratio (I/G) and S(I) did not differ between the AGA and SGA groups. Steroids did not influence the I/G nor the S(I) of AGA infants (10.2 +/- 6.7 vs 8.2 +/- 2.3), but decreased the S(I) in the SGA group (12.2 +/- 5.1 vs 5.3 +/- 2.7, P <.05). CONCLUSIONS: Insulin sensitivity of neonates can be measured by the modified minimal model. IUGR is not associated with impaired fetal glucose tolerance. Early neonatal steroid treatment decreases insulin sensitivity in SGA infants, which may contribute to their risk of having hyperglycemia.     

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.     

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。     

Association between serum leptin and anthropometric parameters at birth and at 15th day of life in infants born asymmetrically small for gestational age

The aim of this study was to investigate changes in skinfold measurements taken at three sites, mid-arm circumference and umbilical circumference during the first 15 days of life; and to evaluate relationships between anthropometric measurements and umbilical cord blood serum leptin levels in infants born small for gestational age (SGA) and appropriate for gestational age (AGA) infants. Of 50 newborn infants, 25 were SGA and 25 were AGA. Neonates' weight, mid-arm circumference (MAC), umbilical circumference (UC), and triceps, subscapular and periumbilical skinfold thicknesses were measured (Holtain callipers) immediately after delivery. Anthropometric parameters were measured again at 15th days of age. At birth, mean birth weight, mean skinfold thickness, MAC and UC measurements in the AGA group were significantly higher than those of the SGA group. These differences were also found on the 15th day. Birth weight correlated with all skinfold thicknesses, MAC and UC at birth. Weight at 15th day of life correlated with skinfold thicknesses, MAC and UC at 15th day of life. Cord blood leptin level was significantly lower in the SGA than in the AGA infants. This difference continued on the 15th day. When cord blood leptin level was compared with that of the 15th day, we found that leptin levels in the cord blood were significantly higher. There were significantly positive correlations between leptin levels and birth weight and skinfold thicknesses when the infants were all grouped together. When the newborns were grouped according to birth weight, there were positive correlations between cord blood serum leptin levels and these parameters in the AGA group, but no correlation in the SGA group. At the 15th day of life serum leptin levels correlated with weight, subscapular and triceps skinfold thickness in the AGA group, but only with triceps skinfold thickness in the SGA group.     

Serum ferritin, iron levels and iron binding capacity in asymmetric SGA babies.

The concentration of serum ferritin reflects the extent of iron stores in premature infants. We aimed to determine serum ferritin levels and iron status in asymmetric small for gestational age (SGA) babies. This study was performed on 21 SGA babies and 19 appropriate for gestational age (AGA) babies. Hemoglobin, iron, iron binding capacity and ferritin levels were investigated in the first six hours after the birth. Hemoglobin levels in the SGA and control groups were 20.9 +/- 1.3 (19.4-23.4 g/dl) and 19.6 +/- 0.8 (18.5-21.5 g/dl), respectively (p = 0.001). Serum ferritin levels in the SGA and AGA groups were 58.36 +/- 20.1 ng/ml and 90.46 +/- 30.5 ng/ml, respectively. Ferritin levels were found lower in the SGA group (p < 0.001). In the SGA group, decreased serum iron and increased iron binding capacity were found but the difference was not significant (p > 0.05). Decreased ferritin levels may result from either impaired iron transport associated with uteroplacental vascular insufficiency or increased iron utilization during enhanced erythropoiesis in conditions characterized by chronic fetal hypoxia. Our results stress the significance of iron supplementation and careful anemia follow-up in term SGA babies. Because anemia progress early, beginning iron therapy as soon as possible is a necessity in SGA babies as in prematures.     

Increased energy expenditure and fecal fat excretion do not impair weight gain in small-for-gestational-age preterm infants.

In order to optimize the nutrition of high-risk premature infants beyond the early postnatal period, a more precise knowledge of individual nutritional requirements is needed. We therefore studied the influence of intrauterine growth retardation on energy expenditure and nutrient utilization determined by indirect calorimetry and fecal fat excretion (steatocrit) in nineteen premature infants who were appropriate-for-gestational-age (AGA; mean gestational age 29.9+/-0.3 weeks, mean birth weight 1.30+/-0.05 kg) and thirteen small-for-gestational-age (SGA) premature infants [mean gestational age 32.4+/-0.5 weeks, mean birth weight 1.024+/-0.07 kg (i.e., below the 10th percentile)] during the first and second month of life. All infants were clinically stable during the study period. In nine SGA infants we observed a significantly higher steatocrit compared to twelve AGA infants (29+/-1 vs. 17+/-1% p = 0.0001). SGA infants (n = 12) also showed a slightly (albeit statistically not significantly) higher energy expenditure than AGA infants (n = 15) (58.7+/-1.9 vs. 53.6+/-1.5 kcal/kg per day, p = 0.054). Despite the increased fat excretion and higher energy expenditure, SGA infants gained weight more rapidly during the study period than AGA infants (20+/-1 vs. 17+/-1 g/kg per day, p = 0.026). We conclude that influences of intrauterine growth retardation on energy expenditure and nutrient utilization persist during the first weeks of extrauterine life. However, these metabolic changes do not impair the capability of SGA infants for extrauterine catch-up growth if adequate nutrition is provided.     

小于胎龄儿青春前期女孩硫化脱氢表雄酮和胰岛素水平的研究

目的探讨小于胎龄儿(SGA)青春前期女孩肾上腺机能初现及是否具有肾上腺机能早现、高肾上腺雄激素血症、高胰岛素血症和胰岛素抵抗现象。方法以符合纳入标准的SGA 39例为研究对象,年龄(7.4±1.7)岁,42例适于胎龄儿(AGA)为对照组,年龄(7.4±1.7)岁。在隔夜空腹12 h后,行身体检查,并抽血检测空腹血糖、胰岛素、硫化脱氢表雄酮(DHEAS)、皮质醇和雌二醇。胰岛素敏感性用空腹血糖与胰岛素乘积的倒数再取自然对数来评价。结果两组中未发现肾上腺机能早现的临床表现,两组间孕母孕龄、年龄、体重指数、空腹血糖、皮质醇、雌二醇和胰岛素敏感性指数差异无统计学意义。SGA组出生体重、研究时的身高和体重均低于AGA组,SGA血清胰岛素和DHEAS水平均高于AGA组(对数转换值:1.076±0.041vs.1.050±0.051,P<0.05;2.637±0.271vs.2.514±0.250,P<0.05)。AGA组DHEAS值在7岁以后出现明显增加,SGA组DHEAS值出现增加的趋势与AGA组比较有所提前。结论AGA女孩肾上腺机能初现的年龄约为7岁,而SGA女孩肾上腺机能初现有始动提前的趋势,青春前期SGA女孩有高肾上腺雄激素血症和胰岛素水平升高的现象,但以胰岛素敏感性指数来评价,尚未发现胰岛素抵抗现象。     

Effect of oral lipid administration on glucose homeostasis in small-for-gestational-age infants

The metabolic effect of feeding with 1.3 g/kg bw lipids (67% medium chain triglycerides) was studied in 15 small-for-gestational age (SGA) term infants. It was compared to a control group of 7 SGA term infants, to 7 term infants with an appropriate birth weight (AGA) and to 7 AGA preterm infants. Plasma glucose concentration rose from (M +/- SE) 3.6 +/- 0.2 to 4.4 +/- 0.3 mmol/l at 30 min in SGA term infants (p less than 0.01). A similar increase was observed in AGA term and preterm infants. The lipid load produced no change in plasma glucagon concentration but a significant increase in insulin/glucagon molar ratio was observed in AGA term infants only. In term SGA infants, the disappearance rate of glucose in plasma after the lipid load was similar to the control: 1.24% per min. The evolution of blood pyruvate and lactate concentration was not modified by the lipid load. Despite lower concentrations of free fatty acids and ketone bodies (KB) in SGA infants than in AGA term infants, the lipid load induced a 120% increase of ketone bodies in SGA infants and a 40% increase only in AGA infants. These data show that these lipids produce a hyperglycemic response in SGA infants as in AGA infants without any change of the disappearance rate of glucose. They suggest that these lipids can stimulate gluconeogenesis and ketogenesis in SGA infants.     

Glucose metabolism soon after birth in very premature infants with small- and appropriate-for-gestational-age birth weights

The intrauterine environment affects the development of insulin resistance in adulthood. To determine the influence of foetal growth restriction on glucose metabolism, we assessed indices of insulin sensitivity soon after birth in very premature infants. Blood samples were collected at birth from 52 premature infants with a gestational age of ≤31 weeks, who were divided into a group whose birth weight was small for their gestational age (SGA group, n=19) and a group whose birth weight was appropriate for their gestational age (AGA group, n=33). Blood glucose, serum insulin and C-peptide immunoreactivity (CPR) levels were measured in both groups. Furthermore, the quantitative insulin check index (QUICKI) was also calculated. Correlations between these indices and glucose metabolism and the standard deviation (SD) score for birth weight were also determined. The levels of insulin and CPR were significantly (p<0.05) lower in the SGA group than in the AGA group. The QUICKI was significantly (p<0.05) higher in the SGA group compared with the AGA group. The SD score for birth weight was correlated with the QUICKI (p<0.01), the serum insulin level (p<0.05) and the CPR level (p<0.05) in all 52 infants. Conclusion: In very premature infants, poor foetal growth may impair foetal insulin secretion and affect the QUICKI at birth.     

母乳喂养对宫内发育迟缓儿胰岛素敏感性影响的随访研究

目的 探讨宫内发育迟缓（IUGR）儿胰岛素敏感性和血清脂联素水平,随访研究母乳喂养对胰岛素敏感性的影响。方法 选择2014年10月至2018年10月住院的足月IUGR儿为IUGR组（106例）,同期出生足月适于胎龄儿（AGA）为AGA组（90例）,记录出生体重、身长,生后7 d检测血清空腹血糖（FG）、三酰甘油（TG）、低密度脂蛋白（LDL）、高密度脂蛋白（HDL）、胰岛素（INS）和脂联素水平,计算胰岛素抵抗指数（HOMA-IR）。将IUGR组按照实际喂养方式,分为母乳喂养组（37例）和配方奶喂养组（42例）,于3月龄、6月龄追踪复测上述血清指标和生长指数。结果 与AGA组比较,IUGR组血清胰岛素、HOMA-IR增高,脂联素水平降低,差异均有统计学意义（P < 0.05）。母乳喂养和配方奶喂养组IUGR儿生后7 d、3月龄、6月龄生长指数、血清FG、TG、LDL和HDL水平差异无统计学意义（P > 0.05）。母乳喂养组血清INS、HOMA-IR水平随母乳喂养时间延长而降低,脂联素水平随母乳喂养时间延长而增高（P < 0.05）。结论 IUGR儿生后早期胰岛素敏感性下降,母乳喂养可改善IUGR儿胰岛素敏感性。     

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.