Obestatin and adropin in Prader-Willi syndrome and nonsyndromic obesity: Associations with weight, BMI-z, and HOMA-IR.

The roles of obestatin and adropin in paediatric obesity are poorly understood. We compared obestatin and adropin concentrations in younger (n = 21) and older children (n = 14) with Prader-Willi syndrome (PWS) and age and BMI-z-matched controls (n = 31). Fasting plasma obestatin and adropin were higher in younger children with PWS than controls; adropin was also higher in older children with PWS. Growth hormone treatment had no effects on obestatin or adropin in PWS. The ratio of ghrelin to obestatin declined from early to late childhood but was higher in older PWS than older controls. Adropin correlated with fasting glucose in the PWS group only. Changes in the ratio of ghrelin to obestatin may suggest changes in the processing of preproghrelin to ghrelin and obestatin during development and differential processing of preproghrelin in PWS.

Changes in cardiometabolic markers in children with Prader-Willi syndrome and nonsyndromic obesity following participation in a home-based physical activity intervention.

BACKGROUND: Physical activity is associated with improved cardiometabolic markers in children with nonsyndromic obesity (NSO). Prader-Willi Syndrome (PWS) is a neurodevelopmental disorder characterized by obesity. OBJECTIVE: To compare cardiometabolic changes in response to a home-based parent-facilitated physical activity intervention between children with PWS or with NSO. METHODS: Participants included 18 children with PWS (age = 10.5 ± 0.7y; body fat = 44.6 ± 2.0%) and 30 children with NSO (age = 9.7 ± 0.2y; body fat = 44.8 ± 1.2%). Active Play @ Home was a 24-week physical activity intervention curriculum containing playground-based and active video games completed 4 days per week. Pre- and post-intervention measurements included physical activity, body composition, blood samples analysed for glucose, insulin, lipids and cytokines, and insulin resistance computed using the homeostatic model of assessment for insulin resistance (HOMA-IR). RESULTS: All children (n = 48) showed a significant decrease in Interleukin-8 (3.64 ± 0.24 vs. 3.06 ± 0.22 pg/mL). Children with obesity who did not gain or who lost body fat percentage (n = 18) demonstrated a significant decrease in HOMA-IR (3.17 ± 0.39 vs. 2.72 ± 0.34) and an increase in high-density lipoprotein (44.30 ± 2.51 vs. 47.29 ± 2.59 mg/dL). All other measurements showed no significant changes. CONCLUSIONS: The most favourable changes in cardiometabolic factors were observed in children with nonsyndromic obesity who demonstrated no gain or a decrease in body fat percentage.

Impact of maternal pre-pregnancy overweight on infant overweight at 1 year of age: associations and sex-specific differences.

BACKGROUND: Maternal overweight or obesity (OWOB) is linked to gestational diabetes, fetal macrosomia and higher rates of caesarean delivery. OBJECTIVES: The study aims to assess whether maternal pre-pregnancy OWOB is associated with infant overweight in a sex-dependent manner, independent of microbiota-altering variables. METHODS: Weight and length measurements of 955 mother-infant pairs were obtained from the Canadian Healthy Infant Longitudinal Development cohort. Maternal pre-pregnancy weight was defined as follows: normal, overweight (25 ≤ body mass index < 30) and obese (body mass index ≥ 30). Age and sex-adjusted weight-for-length z-scores >97th percentile were classified as infant overweight at age 1 year. Associations between pre-pregnancy and infant overweight were determined by linear and logistic regression, adjusting for covariates. RESULTS: Maternal pre-pregnancy OWOB were associated with infant weight-for-length and overweight risk at 1 year. Except for pre-pregnancy obesity, these associations were not attenuated appreciably after adjustment for birth mode, exclusivity of breastfeeding, exposure to antibiotics and infant sex. Yet only boys born to mothers with obesity were three times more likely to become overweight at age 1 independent of microbiota-altering variables. Pre-pregnancy obesity was associated with weight-for-length in male and female infants. CONCLUSIONS: Maternal pre-pregnancy OWOB increases the risk of infant overweight, and this association is more evident in male infants.

Autonomic nervous system dysfunction in obesity and Prader-Willi syndrome: current evidence and implications for future obesity therapies.

The autonomic nervous system (ANS) controls essential functions like breathing, heart rate, digestion, body temperature and hormone levels. Evidence suggests that ANS dysfunction is associated with adult and childhood obesity and plays a role in the distribution of total body fat and the development of obesity-related complications in humans. This review summarizes our current understanding of ANS involvement in the pathogenesis of obesity and Prader-Willi syndrome. Available evidence of ANS dysfunction in the control of energy balance is limited and, in some cases, contradictory. Further investigation in this area is warranted in order to better understand the important contributions of the ANS to regulation of body fat, development of obesity and its comorbidities. Results from these studies will guide the development of novel obesity therapeutics targeting specific ANS dysfunction.