Identification of pharmaceuticals and environmental contaminants as obesogens inducing a locomotion-independent thrifty phenotype.

Obesity is a global pandemic that affects people of all ages. While behavioral, nutritional, and socioeconomic factors all contribute to weight gain, other factors in our immediate environment play an insidious role in the prevalence of obesity. Exposure to environmental and pharmaceutical compounds can be a contributing factor to increased weight gain. Using the zebrafish obesogenic test, our study demonstrates that amiodarone, dibutyl phthalate, rosiglitazone, tributyltin, and triclosan induce a thrifty phenotype under short-term fasting conditions. Diazepam significantly reduces locomotion without exhibiting any obesogenic effect, whereas tributyltin, which has the highest obesogenic potential among the tested compounds, has no effect on locomotion. The obesogen-induced resistance to fat loss is not correlated to inhibition of physical activity and a corresponding reduction in energy expenditure, nor to food consumption. Primary prevention measures to fight against the obesity pandemic may include reducing exposure to obesogens that can induce a thrifty phenotype.