The Study on the Correlation between Milk Adiponection and Growth and Development of Offspring
|Keywords||Adiponectin (APN) human milk weight-for-age Z-scores (WAZ) length-for-age Z-scores (LAZ) weight-for-length Z-scores (WLZ) body mass index Z-scores (zBMI)|
【Objective】To investigate the variation of human breast milk adiponectin (APN) concentration during lactation by detecting the level of APN in maternal breast milk of mother in Shanghai, China, and analyze the relationship of APN concentrations in human breast milk with APN in infant serum. Furthermore, the infants were followed up to determine the association between maternal milk APN and infant body proportionality in the first year of life, the period of greatest human milk exposure. To observe the effect of chronic administration of oral APN during the lactation period on weight gain in neonatal mice.【Methods】Subjects included seventy-three mother-infant pairs from Shanghai International Peace Maternity & Child Health Hospital during Mar to Dec 2008. Breast milk sample was collected through home visit at 2 weeks. At 4,13,26,52 weeks, mother-infant pairs came to our hospital to do anthropometric measurement and to fill questionnaire concerning feeding status. Maternal milk was collected at 4,13,26 weeks and infant serum was draw at 26 weeks. And infant serum was draw at 26 weeks.Weight-for-age Z-scores (WAZ), length-for-age Z-scores (LAZ), weight-for-length Z-scores (WLZ) and body mass index Z-scores (zBMI) of infants up to 1 year of age were calculated using World Health Organization (WHO) standards.To investigate the effect of oral APN administration on weight gain in neonatal mice, from d 1 to d 20 of the whole lactation period, mice from four groups were added APN with different daily oral doses, information about mice’s weight gain was recorded. At weaning, on d 21, mice were killed and serum was obtained.The concentration of APN in maternal milk and serum were measured with commercially available ELISAs (R&D Systems). Then we investigated the variation of maternal milk APN, analyzed the correlation between maternal milk APN and infant serum APN, and determined the association between maternal milk APN and infant anthropometrics. At the same time, we observed the variation of APN level in neonatal mice after chronic administration of oral APN.[Results]1. Variation of maternal milk APNThe concentration of APN in maternal milk at 2,4,13,26 weeks was respectively (14.62μg/L,5.93-140.40μg/L), (7.32μg/L,2.04-29.35μg/L), (6.84μg/L,2.72-15.65μg/L)and (4.88μg/L,1.12-13.38μg/L).2. Influential factors to infant anthropometric indicesTaking WAZ, LAZ, WLZ and zBMI as dependent variables, the APN level, continuously variables and assigned categorical variables as independent variables, multiple stepwise regression analysis was applied. Results demonstrated that the dominant influence to LAZ at 13,26,52 weeks is baseline length, besides the most profound effect to LAZ at 4 weeks is birth weight. Excluding birth weight is the strongest influence to WAZ, zBMI, breast milk APN is the most important factor to WAZ, WLZ and zBMI in regression model at 13,26 and 52 weeks.3. The correlation between maternal milk APN and infant serum APNThere is a positive relationship between maternal milk APN at 13,26 weeks and infant serum APN at 26 weeks (r=0.44,0.42; P<0.05). While maternal milk APN at 2,4 weeks were not related to infant serum APN at 26 weeks (r=0.17,0.25; P>0.05).4. Effect of maternal factors to breast milk APNThere were significantly negative correlation between maternal prenatal (r=-0.26, P<0.05), postpartum 4,13,26 weeks(r=-0.33,-0.26,-0.26; P<0.05) BMI and breast milk APN at 26 weeks.5. The relationship between maternal milk APN and infant growth and developmentHigher milk APN in postpartum 2 weeks was associated with lower infant WAZ at 13,26 and 52 weeks (r=-0.30,-0.31,-0.27; all P<0.05). Milk APN in postpartum 4 weeks was inversely related to infant WAZ, WLZ, zBMI at 4,13,26 and 52 weeks (all P<0.05). Meanwhile, milk APN in postpartum 13 weeks had significantly negative correlation with infant WAZ, WLZ, zBMI at 13,26 and 52 weeks (all P<0.01). Milk APN in postpartum 26 weeks also was inversely associated with infant WAZ, WLZ and zBMI at 52 weeks (r=-0.26,-0.28,-0.28; all P<0.05).6. The variation of APN level in neonatal mice after chronic administration of distinct dosage of oral APNAt the end of the suckling period, the serum APN level of high-dose group was significantly higher than low-dose group. 7. The effect of chronic administration of oral APN during the lactation period on weight gain in neonatal mice.The weight of low-dose group mice was higher than middle-group and high-dose group mice at d 21(P<0.01), and the weight of low-dose group mice was higher than control group at d 7, d 14 and d 21(P<0.01).[Conclusions]Milk APN concentration declined throughout lactation. Maternal milk APN might play a vital role at the growth and development of breastfed infants, particularly closely associated with infant weight. Infant serum APN was clearly related to maternal milk APN. Orally APN administration had an effect on neonatal mice’weight gain.