La glycémie maternelle en grossesse et la leptine dans le sang de cordon : des déterminants de l’adiposité dans l’enfance

Childhood overweight and obesity are serious public health issues that affect both the physical and mental health of children. In the province of Quebec, more than a quarter of children are overweight. Exposure to maternal hyperglycaemia complicated or not by gestational diabetes (GDM), maternal adiposity and excessive gestational weight gain (GWG) are factors predisposing children to develop obesity beyond the traditional risk factors such as genetics. This is the fetal programming of childhood obesity, and a better understanding of its role would allow to identify the risk factors involved and treat them preventively before the fetus acquires developmental adaptations. 2nd trimester glucose levels and cord blood leptin levels – a hormone secreted by adipose tissue and related to fat mass – have been reported to be associated with childhood adiposity. As the programming of adiposity can be influenced by the trimester of exposure to hyperglycaemia, we measured glucose levels of pregnant women from the Gen3G cohort in the 1st and 2nd trimester after standardized glucose tests of 50g and 75g respectively. We showed that an increase in 1st trimester glycaemia is associated with an increase in children’s leptinemia at age 5, whereas 1h and 2h post-75g glycaemia in the 2nd trimester is positively associated with the total body fat percentage obtained by DXA (imaging technique) at 5 years of age. These associations are independent of pre-pregnancy maternal adiposity, GWG, and the child sex. Our second study showed that a decrease in cord blood leptinemia is associated with an increase in adiposity at age 3 in 387 children and this negative association is specific to the boys. These associations were not observed in 3-year-old girls or in 5-year-old children. Our results suggest a fetal programming of childhood adiposity and leptinemia that differs according to the trimester of exposure to maternal hyperglycaemia. Our results also suggest the presence in boys of a critical period of leptin sensitivity towards the end of pregnancy where a lower leptin concentration could disrupt the development of hypothalamic leptin-sensitive neurons, which are involved in the regulation of energy homeostasis, and this would influence the adiposity of boys at the age of 3 years.

Name thesis:degree_name

M. Sc.

Level thesis:degree_level

Maîtrise

Discipline thesis:degree_discipline

Physiologie

Grantor dc:publisher

Université de Sherbrooke

Year dc:date.issued

2023

Author dc:creator

• Blais, Kasandra

Advisors dc:contributor.advisor

• Perron, Patrice
• Bouchard, Luigi

• Leptine
• Adiposité infantile
• DEXA
• Glycémie en grossesse
• Programmation fœtale
• Leptin
• Childhood adiposity
• DXA
• Glucose in pregnancy
• Fetal programming

Language dc:language.iso

fr, en

Handle dc:identifier.uri

http://hdl.handle.net/11143/20236

OAI identifier oai:identifier

oai:usherbrooke.scholaris.ca:11143/20236