van Poppel ⏩
Keywords:Inflammation, lifestyle, obesity, cytokines, gestational diabetes, multilevel regression analyses, neonatal body composition
Research interest:Physical activity (PA) has been shown to affect circulating cytokine levels. In trained individuals, reduced levels of pro-inflammatory cytokines are paralleled by an increase of anti-inflammatory cytokines (1). In addition, our group showed previously that maternal PA has an effect on a number of circulating cytokines in pregnancy, including interleukin (IL)-6 and tumor necrosis factor (TNF)-α (2).
These two cytokines (TNF-α and IL-6) are associated with glucose and insulin metabolism in pregnancy. TNF-α is consistently elevated in GDM (3), and is an independent predictor of insulin resistance in GDM (4). TNF-α has been hypothesized to exert an inhibitory effect on insulin secretion and insulin-regulated glucose uptake in GDM, thus contributing to the sustained hyperglycemia (5). IL-6 is elevated in women, who develop GDM (6) and our group showed that IL-6 is related to insulin sensitivity and insulin response in obese pregnant women (2).
Not only glucose metabolism, but also lipids are associated with cytokines in pregnancy. The group of G. Desoye showed that pro-inflammatory cytokines increase lipase expression and hence free fatty acid availability for transfer to the fetus (7). Low grade inflammation — through cytokines — changes maternal lipids, predominantly triglycerides and free fatty acids, and is related to fetal growth and adiposity (8). It has been postulated that inflammation, mostly IL-6, also influences fetal lipid availability independent of maternal lipids (9). Cytokines, such as IL-6 and TNF-α, modulate free fatty acid availability and thereby can affect fetal growth and body composition.
We hypothesize that physical activity will lead to different maternal and fetal cytokine levels and, through this, change glucose, triglyceride and free fatty acid levels. This will result in changes in fetal growth and neonatal body composition. We will analyze cytokine profiles in obese pregnant women and relate this to physical activity levels and maternal and neonatal outcomes.
Collaborations within the DP-iDP:
Collaborating research groups where PhD students could perform their research stay abroad:
Know-how and infrastructure of the research group:The group of Mireille van Poppel is a recently established group with expertise on physical activity in pregnancy in relation to maternal and neonatal outcomes. Currently, studies are carried out to establish the validity of objective and self-reported measurement instruments of physical activity in pregnancy. The group comprises one post-doctoral fellow, one technician and two PhD students. The group has extensive expertise in epidemiology, statistical analyses and intervention research. These methodologies have been applied to research on lifestyle in pregnancy, specifically in relation to inflammation and metabolic outcomes. The group has access to devices for objective measurement of physical activity (accelerometers) and a physiology laboratory, for measuring physical fitness and energy expenditure.
Scientific concepts and techniques that students will learn in this laboratory:DP-iDP students will be learning to take step back from cells and tissues, and consider the role of maternal characteristics during pregnancy (obesity, lifestyle, mental health) for inflammatory and metabolic outcomes. Basic concepts such as confounding, representativeness, bias, validity and causality will be trained, as well as other relevant epidemiological methods. Students will learn how to analyze clustered datasets (