Poster Presentation The International Congress of Neuroendocrinology 2014

Behavioral consequences of exposure to a high fat diet during the post-weaning period in rats (#141)

Cristina Rabasa 1 , Julia Winsa 1 , Heike Vogel 1 , Suzanne L Dickson 1
  1. University of Gothenburg, Gothenburg, Sweden

Obesity has become a major public health issue over the last decades, and different studies pointed the critical role of dietary interventions in early-life. Less explored are the long-term effects of interventions during the adolescence, a critical period for establishing appetitive and reward-linked behaviors.  Thus, in the present work we exposed adolescent rats (post natal day 21), to normal chow or high fat (HF) diet for 10 days (PN21-PN31). Thereafter, part of the animals (n=70) were moved to chow and tested for long-term effects starting on PN60. Then, we studied the food preferences in a three choice model (high fat, high carbohydrates, high proteins). We analyzed the rewarding properties of chocolate in the conditioned place preference (CPP) test, saccharin preference, anxiety in the elevated plus maze (EPM), and the locomotor response to Quinpirole. The remaining animals (n=24) were tested immediately after the dietary intervention (starting on PN32) for food reward in the CPP and anxiety (EPM). We included one group with rats exposed to HF diet until the end of the experiment (HF-continuous). Strikingly, behavior was unaltered in adult rats transiently fed HF diet post-weaning, suggesting that a short exposure to HF diet doesn’t induce long-term effects in food preferences, reward perception and value of palatable food, anxiety or locomotor activity. Nevertheless, animals in HF-continuous ate less chocolate during the training in the CPP, although they increase preference for the chocolate-paired compartment, suggesting that although they found chocolate more rewarding than chow, they “crave" less for that food. Our results demonstrate that if there is an effect of HF diet during adolescence, it vanishes once the animals go back to a normal chow diet, proving that eating HF diet during adolescence doesn’t alter reward-linked behaviors if the diet is normalized after a short period.  Supported by EC (Nudge-it, 607310).